diff mbox series

[V13,8/9] hw/mips: Add Loongson-3 machine support

Message ID 1602059975-10115-9-git-send-email-chenhc@lemote.com (mailing list archive)
State New, archived
Headers show
Series mips: Add Loongson-3 machine support | expand

Commit Message

chen huacai Oct. 7, 2020, 8:39 a.m. UTC
Add Loongson-3 based machine support, it use liointc as the interrupt
controler and use GPEX as the pci controller. Currently it can work with
both TCG and KVM.

As the machine model is not based on any exiting physical hardware, the
name of the machine is "loongson3-virt". It may be superseded in future
by a real machine model. If this happens, then a regular deprecation
procedure shall occur for "loongson3-virt" machine.

We now already have a full functional Linux kernel (based on Linux-5.4.x
LTS, the kvm host side and guest side have both been upstream for Linux-
5.9, but Linux-5.9 has not been released yet) here:

https://github.com/chenhuacai/linux

Of course the upstream kernel is also usable (though it is "unstable"
now):

https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git

How to use QEMU/Loongson-3?
1, Download kernel source from the above URL;
2, Build a kernel with arch/mips/configs/loongson3_defconfig;
3, Boot a Loongson-3A4000 host with this kernel (for KVM mode);
4, Build QEMU-master with this patchset;
5, modprobe kvm (only necessary for KVM mode);
6, Use QEMU with TCG:
       qemu-system-mips64el -M loongson3-virt,accel=tcg -cpu Loongson-3A1000 -kernel <path_to_kernel> -append ...
   Use QEMU with KVM:
       qemu-system-mips64el -M loongson3-virt,accel=kvm -cpu Loongson-3A4000 -kernel <path_to_kernel> -append ...

   The "-cpu" parameter is optional here and QEMU will use the correct type for TCG/KVM automatically.

Signed-off-by: Huacai Chen <chenhc@lemote.com>
Co-developed-by: Jiaxun Yang <jiaxun.yang@flygoat.com>
---
 default-configs/devices/mips64el-softmmu.mak |   1 +
 hw/mips/Kconfig                              |  12 +
 hw/mips/loongson3_bootp.c                    | 162 +++++++
 hw/mips/loongson3_bootp.h                    | 225 ++++++++++
 hw/mips/loongson3_virt.c                     | 615 +++++++++++++++++++++++++++
 hw/mips/meson.build                          |   1 +
 6 files changed, 1016 insertions(+)
 create mode 100644 hw/mips/loongson3_bootp.c
 create mode 100644 hw/mips/loongson3_bootp.h
 create mode 100644 hw/mips/loongson3_virt.c

Comments

Philippe Mathieu-Daudé Oct. 10, 2020, 9:09 a.m. UTC | #1
Hi Huacai,

On 10/7/20 10:39 AM, Huacai Chen wrote:
> Add Loongson-3 based machine support, it use liointc as the interrupt
> controler and use GPEX as the pci controller. Currently it can work with
> both TCG and KVM.
> 
> As the machine model is not based on any exiting physical hardware, the
> name of the machine is "loongson3-virt". It may be superseded in future
> by a real machine model. If this happens, then a regular deprecation
> procedure shall occur for "loongson3-virt" machine.
> 
> We now already have a full functional Linux kernel (based on Linux-5.4.x
> LTS, the kvm host side and guest side have both been upstream for Linux-
> 5.9, but Linux-5.9 has not been released yet) here:
> 
> https://github.com/chenhuacai/linux
> 
> Of course the upstream kernel is also usable (though it is "unstable"
> now):
> 
> https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
> 
> How to use QEMU/Loongson-3?
> 1, Download kernel source from the above URL;
> 2, Build a kernel with arch/mips/configs/loongson3_defconfig;
> 3, Boot a Loongson-3A4000 host with this kernel (for KVM mode);
> 4, Build QEMU-master with this patchset;
> 5, modprobe kvm (only necessary for KVM mode);
> 6, Use QEMU with TCG:
>         qemu-system-mips64el -M loongson3-virt,accel=tcg -cpu Loongson-3A1000 -kernel <path_to_kernel> -append ...
>     Use QEMU with KVM:
>         qemu-system-mips64el -M loongson3-virt,accel=kvm -cpu Loongson-3A4000 -kernel <path_to_kernel> -append ...
> 
>     The "-cpu" parameter is optional here and QEMU will use the correct type for TCG/KVM automatically.
> 
> Signed-off-by: Huacai Chen <chenhc@lemote.com>
> Co-developed-by: Jiaxun Yang <jiaxun.yang@flygoat.com>
> ---
>   default-configs/devices/mips64el-softmmu.mak |   1 +
>   hw/mips/Kconfig                              |  12 +
>   hw/mips/loongson3_bootp.c                    | 162 +++++++
>   hw/mips/loongson3_bootp.h                    | 225 ++++++++++

In a previous version I asked if you could split the bootp* files
(firmware related) in a previous separate patch to ease the review
of the machine part.

>   hw/mips/loongson3_virt.c                     | 615 +++++++++++++++++++++++++++
>   hw/mips/meson.build                          |   1 +
>   6 files changed, 1016 insertions(+)
[...]

> diff --git a/hw/mips/loongson3_virt.c b/hw/mips/loongson3_virt.c
> new file mode 100644
> index 0000000..4e573d6
> --- /dev/null
> +++ b/hw/mips/loongson3_virt.c
> @@ -0,0 +1,615 @@
> +/*
> + * Generic Loongson-3 Platform support
> + *
> + * Copyright (c) 2017-2020 Huacai Chen (chenhc@lemote.com)
> + * Copyright (c) 2017-2020 Jiaxun Yang <jiaxun.yang@flygoat.com>
> + *
> + * This program is free software: you can redistribute it and/or modify
> + * it under the terms of the GNU General Public License as published by
> + * the Free Software Foundation, either version 2 of the License, or
> + * (at your option) any later version.
> + *
> + * This program is distributed in the hope that it will be useful,
> + * but WITHOUT ANY WARRANTY; without even the implied warranty of
> + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
> + * GNU General Public License for more details.
> + *
> + * You should have received a copy of the GNU General Public License
> + * along with this program. If not, see <https://www.gnu.org/licenses/>.
> + */
> +
> +/*
> + * Generic virtualized PC Platform based on Loongson-3 CPU (MIPS64R2 with
> + * extensions, 800~2000MHz)
> + */
> +
> +#include "qemu/osdep.h"
> +#include "qemu-common.h"
> +#include "qemu/units.h"
> +#include "qemu/cutils.h"
> +#include "qapi/error.h"
> +#include "cpu.h"
> +#include "elf.h"
> +#include "kvm_mips.h"
> +#include "hw/boards.h"
> +#include "hw/char/serial.h"
> +#include "hw/mips/mips.h"
> +#include "hw/mips/cpudevs.h"
> +#include "hw/mips/fw_cfg.h"
> +#include "hw/mips/loongson3_bootp.h"
> +#include "hw/misc/unimp.h"
> +#include "hw/intc/i8259.h"
> +#include "hw/loader.h"
> +#include "hw/isa/superio.h"
> +#include "hw/pci/msi.h"
> +#include "hw/pci/pci.h"
> +#include "hw/pci/pci_host.h"
> +#include "hw/pci-host/gpex.h"
> +#include "hw/rtc/mc146818rtc.h"
> +#include "hw/usb.h"
> +#include "net/net.h"
> +#include "exec/address-spaces.h"
> +#include "sysemu/kvm.h"
> +#include "sysemu/qtest.h"
> +#include "sysemu/reset.h"
> +#include "sysemu/runstate.h"
> +#include "qemu/log.h"
> +#include "qemu/error-report.h"
> +
> +#define PM_CNTL_MODE          0x10
> +
> +#define LOONGSON_MAX_VCPUS      16
> +
> +#define LOONGSON3_BIOSNAME "bios_loongson3.bin"

Where is that file?

> +
> +#define UART_IRQ            0
> +#define RTC_IRQ             1
> +#define PCIE_IRQ_BASE       2
> +
> +const struct MemmapEntry virt_memmap[] = {
> +    [VIRT_LOWMEM] =      { 0x00000000,    0x10000000 },
> +    [VIRT_PM] =          { 0x10080000,         0x100 },
> +    [VIRT_FW_CFG] =      { 0x10080100,         0x100 },
> +    [VIRT_RTC] =         { 0x10081000,        0x1000 },
> +    [VIRT_PCIE_PIO] =    { 0x18000000,       0x80000 },
> +    [VIRT_PCIE_ECAM] =   { 0x1a000000,     0x2000000 },
> +    [VIRT_BIOS_ROM] =    { 0x1fc00000,      0x200000 },
> +    [VIRT_UART] =        { 0x1fe001e0,           0x8 },

See below about this mapping.

> +    [VIRT_LIOINTC] =     { 0x3ff01400,          0x64 },
> +    [VIRT_PCIE_MMIO] =   { 0x40000000,    0x40000000 },
> +    [VIRT_HIGHMEM] =     { 0x80000000,           0x0 }, /* Variable */
> +};
> +
> +static const struct MemmapEntry loader_memmap[] = {
> +    [LOADER_KERNEL] =    { 0x00000000,     0x4000000 },
> +    [LOADER_INITRD] =    { 0x04000000,           0x0 }, /* Variable */
> +    [LOADER_CMDLINE] =   { 0x0ff00000,      0x100000 },
> +};
> +
> +static const struct MemmapEntry loader_rommap[] = {
> +    [LOADER_BOOTROM] =   { 0x1fc00000,        0x1000 },
> +    [LOADER_PARAM] =     { 0x1fc01000,       0x10000 },
> +};
> +
> +static struct _loaderparams {
> +    uint64_t cpu_freq;
> +    uint64_t ram_size;
> +    const char *kernel_cmdline;
> +    const char *kernel_filename;
> +    const char *initrd_filename;
> +    uint64_t kernel_entry;
> +    uint64_t a0, a1, a2;
> +} loaderparams;
> +
> +static uint64_t loongson3_pm_read(void *opaque, hwaddr addr, unsigned size)
> +{
> +    return 0;
> +}
> +
> +static void loongson3_pm_write(void *opaque, hwaddr addr, uint64_t val, unsigned size)
> +{
> +    if (addr != PM_CNTL_MODE) {
> +        return;
> +    }
> +
> +    switch (val) {
> +    case 0x00:
> +        qemu_system_reset_request(SHUTDOWN_CAUSE_GUEST_RESET);
> +        return;
> +    case 0xff:
> +        qemu_system_shutdown_request(SHUTDOWN_CAUSE_GUEST_SHUTDOWN);
> +        return;
> +    default:
> +        return;
> +    }
> +}
> +
> +static const MemoryRegionOps loongson3_pm_ops = {
> +    .read  = loongson3_pm_read,
> +    .write = loongson3_pm_write,
> +    .endianness = DEVICE_NATIVE_ENDIAN,
> +};
> +
> +#define DEF_TCG_FREQ (200 * 1000 * 1000)
> +#define DEF_KVM_FREQ (1600 * 1000 * 1000)
> +
> +static uint64_t get_cpu_freq(void)
> +{
> +#ifdef CONFIG_KVM
> +    int ret;
> +    uint64_t freq;
> +    struct kvm_one_reg freq_reg = {
> +        .id = KVM_REG_MIPS_COUNT_HZ,
> +        .addr = (uintptr_t)(&freq)
> +    };
> +
> +    if (kvm_enabled()) {
> +        ret = kvm_vcpu_ioctl(first_cpu, KVM_GET_ONE_REG, &freq_reg);
> +        if (ret < 0) {
> +            return DEF_KVM_FREQ;
> +        }
> +        return freq * 2;
> +    } else {
> +        /*
> +         * TCG has a default CP0 Timer period 10 ns, which is 100MHz,
> +         * CPU frequency is defined as double of CP0 timer frequency.
> +         */
> +        return DEF_TCG_FREQ;
> +    }
> +#else
> +    return DEF_TCG_FREQ;
> +#endif
> +}
> +
> +static void init_boot_param(void)
> +{
> +    void *p;
> +    struct boot_params *bp;
> +
> +    p = g_malloc0(loader_rommap[LOADER_PARAM].size);
> +    bp = p;
> +
> +    stw_le_p(&bp->efi.smbios.vers, 1);
> +    init_reset_system(&(bp->reset_system));
> +    p += ROUND_UP(sizeof(struct boot_params), 64);
> +    init_loongson_params(&(bp->efi.smbios.lp), p,
> +                         loaderparams.cpu_freq, loaderparams.ram_size);
> +
> +    rom_add_blob_fixed("params_rom", bp,
> +                       loader_rommap[LOADER_PARAM].size,
> +                       loader_rommap[LOADER_PARAM].base);
> +
> +    g_free(bp);
> +
> +    loaderparams.a2 = cpu_mips_phys_to_kseg0(NULL, loader_rommap[LOADER_PARAM].base);
> +}
> +
> +static void init_boot_rom(void)
> +{
> +    const unsigned int boot_code[] = {
> +        0x40086000,   /* mfc0    t0, CP0_STATUS                               */
> +        0x240900E4,   /* li      t1, 0xe4         #set kx, sx, ux, erl        */
> +        0x01094025,   /* or      t0, t0, t1                                   */
> +        0x3C090040,   /* lui     t1, 0x40         #set bev                    */
> +        0x01094025,   /* or      t0, t0, t1                                   */
> +        0x40886000,   /* mtc0    t0, CP0_STATUS                               */
> +        0x00000000,
> +        0x40806800,   /* mtc0    zero, CP0_CAUSE                              */
> +        0x00000000,
> +        0x400A7801,   /* mfc0    t2, $15, 1                                   */
> +        0x314A00FF,   /* andi    t2, 0x0ff                                    */
> +        0x3C089000,   /* dli     t0, 0x900000003ff01000                       */
> +        0x00084438,
> +        0x35083FF0,
> +        0x00084438,
> +        0x35081000,
> +        0x314B0003,   /* andi    t3, t2, 0x3      #local cpuid                */
> +        0x000B5A00,   /* sll     t3, 8                                        */
> +        0x010B4025,   /* or      t0, t0, t3                                   */
> +        0x314C000C,   /* andi    t4, t2, 0xc      #node id                    */
> +        0x000C62BC,   /* dsll    t4, 42                                       */
> +        0x010C4025,   /* or      t0, t0, t4                                   */
> +                      /* WaitForInit:                                         */
> +        0xDD020020,   /* ld      v0, FN_OFF(t0)   #FN_OFF 0x020               */
> +        0x1040FFFE,   /* beqz    v0, WaitForInit                              */
> +        0x00000000,   /* nop                                                  */
> +        0xDD1D0028,   /* ld      sp, SP_OFF(t0)   #FN_OFF 0x028               */
> +        0xDD1C0030,   /* ld      gp, GP_OFF(t0)   #FN_OFF 0x030               */
> +        0xDD050038,   /* ld      a1, A1_OFF(t0)   #FN_OFF 0x038               */
> +        0x00400008,   /* jr      v0               #byebye                     */
> +        0x00000000,   /* nop                                                  */
> +        0x1000FFFF,   /* 1:  b   1b                                           */
> +        0x00000000,   /* nop                                                  */
> +
> +                      /* Reset                                                */
> +        0x3C0C9000,   /* dli     t0, 0x9000000010080010                       */
> +        0x358C0000,
> +        0x000C6438,
> +        0x358C1008,
> +        0x000C6438,
> +        0x358C0010,
> +        0x240D0000,   /* li      t1, 0x00                                     */
> +        0xA18D0000,   /* sb      t1, (t0)                                     */
> +        0x1000FFFF,   /* 1:  b   1b                                           */
> +        0x00000000,   /* nop                                                  */
> +
> +                      /* Shutdown                                             */
> +        0x3C0C9000,   /* dli     t0, 0x9000000010080010                       */
> +        0x358C0000,
> +        0x000C6438,
> +        0x358C1008,
> +        0x000C6438,
> +        0x358C0010,
> +        0x240D00FF,   /* li      t1, 0xff                                     */
> +        0xA18D0000,   /* sb      t1, (t0)                                     */
> +        0x1000FFFF,   /* 1:  b   1b                                           */
> +        0x00000000    /* nop                                                  */
> +    };
> +
> +    rom_add_blob_fixed("boot_rom", boot_code, sizeof(boot_code),
> +                        loader_rommap[LOADER_BOOTROM].base);
> +}
> +
> +static void fw_cfg_boot_set(void *opaque, const char *boot_device,
> +                            Error **errp)
> +{
> +    fw_cfg_modify_i16(opaque, FW_CFG_BOOT_DEVICE, boot_device[0]);
> +}
> +
> +static void fw_conf_init(unsigned long ram_size)
> +{
> +    FWCfgState *fw_cfg;
> +    hwaddr cfg_addr = virt_memmap[VIRT_FW_CFG].base;
> +
> +    fw_cfg = fw_cfg_init_mem_wide(cfg_addr, cfg_addr + 8, 8, 0, NULL);
> +    fw_cfg_add_i16(fw_cfg, FW_CFG_NB_CPUS, (uint16_t)current_machine->smp.cpus);
> +    fw_cfg_add_i16(fw_cfg, FW_CFG_MAX_CPUS, (uint16_t)current_machine->smp.max_cpus);
> +    fw_cfg_add_i64(fw_cfg, FW_CFG_RAM_SIZE, (uint64_t)ram_size);
> +    fw_cfg_add_i32(fw_cfg, FW_CFG_MACHINE_VERSION, 1);
> +    fw_cfg_add_i64(fw_cfg, FW_CFG_CPU_FREQ, get_cpu_freq());
> +    qemu_register_boot_set(fw_cfg_boot_set, fw_cfg);
> +}
> +
> +static int set_prom_cmdline(ram_addr_t initrd_offset, long initrd_size)
> +{
> +    hwaddr cmdline_vaddr;
> +    char memenv[32];
> +    char highmemenv[32];
> +    void *cmdline_buf;
> +    unsigned int *parg_env;
> +    int ret = 0;
> +
> +    /* Allocate cmdline_buf for command line. */
> +    cmdline_buf = g_malloc0(loader_memmap[LOADER_CMDLINE].size);
> +    cmdline_vaddr = cpu_mips_phys_to_kseg0(NULL,
> +                                           loader_memmap[LOADER_CMDLINE].base);
> +
> +    /*
> +     * Layout of cmdline_buf looks like this:
> +     * argv[0], argv[1], 0, env[0], env[1], ... env[i], 0,
> +     * argv[0]'s data, argv[1]'s data, env[0]'data, ..., env[i]'s data, 0
> +     */
> +    parg_env = (void *)cmdline_buf;
> +
> +    ret = (3 + 1) * 4;
> +    *parg_env++ = cmdline_vaddr + ret;
> +    ret += (1 + snprintf(cmdline_buf + ret, 256 - ret, "g"));
> +
> +    /* argv1 */
> +    *parg_env++ = cmdline_vaddr + ret;
> +    if (initrd_size > 0)
> +        ret += (1 + snprintf(cmdline_buf + ret, 256 - ret,
> +                "rd_start=0x" TARGET_FMT_lx " rd_size=%li %s",
> +                cpu_mips_phys_to_kseg0(NULL, initrd_offset),
> +                initrd_size, loaderparams.kernel_cmdline));
> +    else
> +        ret += (1 + snprintf(cmdline_buf + ret, 256 - ret, "%s",
> +                loaderparams.kernel_cmdline));
> +
> +    /* argv2 */
> +    *parg_env++ = cmdline_vaddr + 4 * ret;
> +
> +    /* env */
> +    sprintf(memenv, "%d", 256);
> +    sprintf(highmemenv, "%ld", (unsigned long)(loaderparams.ram_size / MiB) - 256);
> +
> +    rom_add_blob_fixed("cmdline", cmdline_buf,
> +                       loader_memmap[LOADER_CMDLINE].size,
> +                       loader_memmap[LOADER_CMDLINE].base);
> +
> +    g_free(cmdline_buf);
> +
> +    loaderparams.a0 = 2;
> +    loaderparams.a1 = cmdline_vaddr;
> +
> +    return 0;
> +}
> +
> +static uint64_t load_kernel(CPUMIPSState *env)
> +{
> +    long kernel_size;
> +    ram_addr_t initrd_offset;
> +    uint64_t kernel_entry, kernel_low, kernel_high, initrd_size;
> +
> +    kernel_size = load_elf(loaderparams.kernel_filename, NULL,
> +                           cpu_mips_kseg0_to_phys, NULL,
> +                           (uint64_t *)&kernel_entry,
> +                           (uint64_t *)&kernel_low, (uint64_t *)&kernel_high,
> +                           NULL, 0, EM_MIPS, 1, 0);
> +    if (kernel_size < 0) {
> +        error_report("could not load kernel '%s': %s",
> +                     loaderparams.kernel_filename,
> +                     load_elf_strerror(kernel_size));
> +        exit(1);
> +    }
> +
> +    /* load initrd */
> +    initrd_size = 0;
> +    initrd_offset = 0;
> +    if (loaderparams.initrd_filename) {
> +        initrd_size = get_image_size(loaderparams.initrd_filename);
> +        if (initrd_size > 0) {
> +            initrd_offset = (kernel_high + ~INITRD_PAGE_MASK) &
> +                            INITRD_PAGE_MASK;
> +            initrd_offset = MAX(initrd_offset,
> +                                loader_memmap[LOADER_INITRD].base);
> +
> +            if (initrd_offset + initrd_size > ram_size) {
> +                error_report("memory too small for initial ram disk '%s'",
> +                             loaderparams.initrd_filename);
> +                exit(1);
> +            }
> +
> +            initrd_size = load_image_targphys(loaderparams.initrd_filename,
> +                                              initrd_offset,
> +                                              ram_size - initrd_offset);
> +        }
> +
> +        if (initrd_size == (target_ulong) -1) {
> +            error_report("could not load initial ram disk '%s'",
> +                         loaderparams.initrd_filename);
> +            exit(1);
> +        }
> +    }
> +
> +    /* Setup prom cmdline. */
> +    set_prom_cmdline(initrd_offset, initrd_size);
> +
> +    return kernel_entry;
> +}
> +
> +static void main_cpu_reset(void *opaque)
> +{
> +    MIPSCPU *cpu = opaque;
> +    CPUMIPSState *env = &cpu->env;
> +
> +    cpu_reset(CPU(cpu));
> +
> +    /* Loongson-3 reset stuff */
> +    if (loaderparams.kernel_filename) {
> +        if (cpu == MIPS_CPU(first_cpu)) {
> +            env->active_tc.gpr[4] = loaderparams.a0;
> +            env->active_tc.gpr[5] = loaderparams.a1;
> +            env->active_tc.gpr[6] = loaderparams.a2;
> +            env->active_tc.PC = loaderparams.kernel_entry;
> +        }
> +        env->CP0_Status &= ~((1 << CP0St_BEV) | (1 << CP0St_ERL));
> +    }
> +}
> +
> +static inline void loongson3_virt_devices_init(MachineState *machine, DeviceState *pic)
> +{
> +    int i;
> +    qemu_irq irq;
> +    PCIBus *pci_bus;
> +    DeviceState *dev;
> +    MemoryRegion *pio_alias;
> +    MemoryRegion *mmio_alias, *mmio_reg;
> +    MemoryRegion *ecam_alias, *ecam_reg;
> +
> +    dev = qdev_new(TYPE_GPEX_HOST);
> +    sysbus_realize_and_unref(SYS_BUS_DEVICE(dev), &error_fatal);
> +    pci_bus = PCI_HOST_BRIDGE(dev)->bus;
> +
> +    ecam_alias = g_new0(MemoryRegion, 1);
> +    ecam_reg = sysbus_mmio_get_region(SYS_BUS_DEVICE(dev), 0);
> +    memory_region_init_alias(ecam_alias, OBJECT(dev), "pcie-ecam",
> +                             ecam_reg, 0, virt_memmap[VIRT_PCIE_ECAM].size);
> +    memory_region_add_subregion(get_system_memory(),
> +                                virt_memmap[VIRT_PCIE_ECAM].base, ecam_alias);
> +
> +    mmio_alias = g_new0(MemoryRegion, 1);
> +    mmio_reg = sysbus_mmio_get_region(SYS_BUS_DEVICE(dev), 1);
> +    memory_region_init_alias(mmio_alias, OBJECT(dev), "pcie-mmio",
> +                             mmio_reg, virt_memmap[VIRT_PCIE_MMIO].base,
> +                             virt_memmap[VIRT_PCIE_MMIO].size);
> +    memory_region_add_subregion(get_system_memory(),
> +                                virt_memmap[VIRT_PCIE_MMIO].base, mmio_alias);
> +
> +    pio_alias = g_new0(MemoryRegion, 1);
> +    memory_region_init_alias(pio_alias, OBJECT(dev), "pcie-pio",
> +                             get_system_io(), 0, virt_memmap[VIRT_PCIE_PIO].size);
> +    memory_region_add_subregion(get_system_memory(),
> +                                virt_memmap[VIRT_PCIE_PIO].base, pio_alias);
> +    sysbus_mmio_map(SYS_BUS_DEVICE(dev), 2, virt_memmap[VIRT_PCIE_PIO].base);
> +
> +    for (i = 0; i < GPEX_NUM_IRQS; i++) {
> +        irq = qdev_get_gpio_in(pic, PCIE_IRQ_BASE + i);
> +        sysbus_connect_irq(SYS_BUS_DEVICE(dev), i, irq);
> +        gpex_set_irq_num(GPEX_HOST(dev), i, PCIE_IRQ_BASE + i);
> +    }
> +
> +    pci_vga_init(pci_bus);
> +
> +    if (defaults_enabled()) {
> +        pci_create_simple(pci_bus, -1, "pci-ohci");
> +        usb_create_simple(usb_bus_find(-1), "usb-kbd");
> +        usb_create_simple(usb_bus_find(-1), "usb-tablet");
> +    }
> +
> +    for (i = 0; i < nb_nics; i++) {
> +        NICInfo *nd = &nd_table[i];
> +
> +        if (!nd->model) {
> +            nd->model = g_strdup("virtio");
> +        }
> +
> +        pci_nic_init_nofail(nd, pci_bus, nd->model, NULL);
> +    }
> +}
> +
> +static void mips_loongson3_virt_init(MachineState *machine)
> +{
> +    int i;
> +    long bios_size;
> +    MIPSCPU *cpu;
> +    CPUMIPSState *env;
> +    DeviceState *liointc;
> +    char *filename;
> +    const char *kernel_cmdline = machine->kernel_cmdline;
> +    const char *kernel_filename = machine->kernel_filename;
> +    const char *initrd_filename = machine->initrd_filename;
> +    ram_addr_t ram_size = machine->ram_size;
> +    MemoryRegion *address_space_mem = get_system_memory();
> +    MemoryRegion *ram = g_new(MemoryRegion, 1);
> +    MemoryRegion *bios = g_new(MemoryRegion, 1);
> +    MemoryRegion *iomem = g_new(MemoryRegion, 1);
> +
> +    /* TODO: TCG will support all CPU types */
> +    if (!kvm_enabled()) {
> +        if (!machine->cpu_type) {
> +            machine->cpu_type = MIPS_CPU_TYPE_NAME("Loongson-3A1000");
> +        }
> +        if (!strstr(machine->cpu_type, "Loongson-3A1000")) {
> +            error_report("Loongson-3/TCG needs cpu type Loongson-3A1000");
> +            exit(1);
> +        }

IIUC here you need to check machine->smp.cpus is 4 or 8 for the 3A1000.
It would be easier if you model this as a qdev SoC, and this model
cares to create the 4/8 cores (QEMU MIPSCPU).

You defined max_cpu = LOONGSON_MAX_VCPUS = 16, this seems an impossible
configuration for the 3A1000.

> +    } else {
> +        if (!machine->cpu_type) {
> +            machine->cpu_type = MIPS_CPU_TYPE_NAME("Loongson-3A4000");
> +        }
> +        if (!strstr(machine->cpu_type, "Loongson-3A4000")) {
> +            error_report("Loongson-3/KVM needs cpu type Loongson-3A4000");
> +            exit(1);
> +        }

Similar comment, as the 3A4000 is also a quad-core.

> +    }
> +
> +    if (ram_size < 512 * MiB) {
> +        error_report("Loongson-3 machine needs at least 512MB memory");
> +        exit(1);
> +    }
> +
> +    /*
> +     * The whole MMIO range among configure registers doesn't generate
> +     * exception when accessing invalid memory. Create an unimplememted
> +     * device to emulate this feature.
> +     */
> +    create_unimplemented_device("fallback", 0x10000000, 0x30000000);

The secondary crosswise switch description is hard to follow:

* 2.4 Address routing distribution and configuration

According  to  the  default  register  configuration,  CPU [...] 
0x10000000-0x1fffffff  of  CPU  (256M)  is  mapped  to 
0x10000000-0x1fffffff  of  PCI,  and  0x80000000  of  PCIDMA.
In addition, when read access to illegal addresses occurs due to CPU 
guess execution, all 8 address Windows fail to hit, ?

Table 2-9 XBAR level 2 default address configuration
                   base                    high                     owner
0 x0000_0000_1000_0000  0 x0000_0000_2000_0000  Low speed I/O (PCI, etc)

* 14.4 Secondary cross-switch address window

After the address window is configured, the system address 
0x0000_2000_0000 is added-- 0x0000_2FFFF_FFFF  maps  to 
0x0000_0000_0000  -- 0x0000_0FFF_FFFF  of  memory  controller 0.An 
access to 0x0000_2000_0000 at this time will result in the original 
enabledThe value stored at address 0x0000_0000_0000.

But see:

* 14.6.3 Low speed device address window

Here are defined the peripherals in the 0x1c00_0000-0x1ff0_ffff range.

* 15.1 System memory space

IO device, 0x1000_0000 --  0x1FFF_FFFF

* 16 Memory allocation for system X

... divide  the  256M  PCI  space  (0x10000000~0x20000000)  into  two 
parts:  0x10000000~0x17ffffff for mem space and 0x18000000~0x20000000 
for IO space.

I still don't understand what is in the 0x20000000-0x30000000 range.

> +
> +    liointc = qdev_new("loongson.liointc");
> +    sysbus_realize_and_unref(SYS_BUS_DEVICE(liointc), &error_fatal);
> +
> +    sysbus_mmio_map(SYS_BUS_DEVICE(liointc), 0, virt_memmap[VIRT_LIOINTC].base);
> +
> +    for (i = 0; i < machine->smp.cpus; i++) {
> +        int ip;
> +
> +        /* init CPUs */
> +        cpu = MIPS_CPU(cpu_create(machine->cpu_type));
> +
> +        /* Init internal devices */
> +        cpu_mips_irq_init_cpu(cpu);
> +        cpu_mips_clock_init(cpu);
> +        qemu_register_reset(main_cpu_reset, cpu);
> +
> +        if (i >= 4) {
> +            continue; /* Only node-0 can be connected to LIOINTC */
> +        }
> +
> +        for (ip = 0; ip < 4 ; ip++) {
> +            int pin = i * 4 + ip;
> +            sysbus_connect_irq(SYS_BUS_DEVICE(liointc),
> +                               pin, cpu->env.irq[ip + 2]);
> +        }
> +    }
> +    env = &MIPS_CPU(first_cpu)->env;
> +
> +    /* Allocate RAM/BIOS, 0x00000000~0x10000000 is alias of 0x80000000~0x90000000 */
> +    memory_region_init_rom(bios, NULL, "loongson3.bios",
> +                           virt_memmap[VIRT_BIOS_ROM].size, &error_fatal);
> +    memory_region_init_alias(ram, NULL, "loongson3.lowmem",
> +                           machine->ram, 0, virt_memmap[VIRT_LOWMEM].size);
> +    memory_region_init_io(iomem, NULL, &loongson3_pm_ops,
> +                           NULL, "loongson3_pm", virt_memmap[VIRT_PM].size);
> +
> +    memory_region_add_subregion(address_space_mem,
> +                      virt_memmap[VIRT_LOWMEM].base, ram);
> +    memory_region_add_subregion(address_space_mem,
> +                      virt_memmap[VIRT_BIOS_ROM].base, bios);
> +    memory_region_add_subregion(address_space_mem,
> +                      virt_memmap[VIRT_HIGHMEM].base, machine->ram);
> +    memory_region_add_subregion(address_space_mem,
> +                      virt_memmap[VIRT_PM].base, iomem);
> +
> +    /*
> +     * We do not support flash operation, just loading bios.bin as raw BIOS.
> +     * Please use -L to set the BIOS path and -bios to set bios name.
> +     */
> +
> +    if (kernel_filename) {
> +        loaderparams.cpu_freq = get_cpu_freq();
> +        loaderparams.ram_size = ram_size;
> +        loaderparams.kernel_filename = kernel_filename;
> +        loaderparams.kernel_cmdline = kernel_cmdline;
> +        loaderparams.initrd_filename = initrd_filename;
> +        loaderparams.kernel_entry = load_kernel(env);
> +
> +        init_boot_rom();
> +        init_boot_param();
> +    } else {
> +        if (bios_name == NULL) {
> +                bios_name = LOONGSON3_BIOSNAME;
> +        }
> +        filename = qemu_find_file(QEMU_FILE_TYPE_BIOS, bios_name);
> +        if (filename) {
> +            bios_size = load_image_targphys(filename,
> +                                            virt_memmap[VIRT_BIOS_ROM].base,
> +                                            virt_memmap[VIRT_BIOS_ROM].size);
> +            g_free(filename);
> +        } else {
> +            bios_size = -1;
> +        }
> +
> +        if ((bios_size < 0 || bios_size > virt_memmap[VIRT_BIOS_ROM].size) &&
> +            !kernel_filename && !qtest_enabled()) {
> +            error_report("Could not load MIPS bios '%s'", bios_name);
> +            exit(1);
> +        }
> +
> +        fw_conf_init(ram_size);
> +    }
> +
> +    msi_nonbroken = true;
> +    loongson3_virt_devices_init(machine, liointc);
> +
> +    sysbus_create_simple("goldfish_rtc", virt_memmap[VIRT_RTC].base,
> +                         qdev_get_gpio_in(liointc, RTC_IRQ));
> +
> +    serial_mm_init(address_space_mem, virt_memmap[VIRT_UART].base, 0,
> +                   qdev_get_gpio_in(liointc, UART_IRQ), 115200, serial_hd(0),
> +                   DEVICE_NATIVE_ENDIAN);

You need to split the SoC part from the machine part.

> +}
> +
> +static void mips_loongson3_virt_machine_init(MachineClass *mc)
> +{
> +    mc->desc = "Loongson-3 Virtualization Platform";
> +    mc->init = mips_loongson3_virt_init;
> +    mc->block_default_type = IF_IDE;

Don't you need min_cpus = 4?

> +    mc->max_cpus = LOONGSON_MAX_VCPUS;
> +    mc->default_ram_id = "loongson3.highram";
> +    mc->default_ram_size = 1600 * MiB;
> +    mc->kvm_type = mips_kvm_type;
> +    mc->minimum_page_bits = 14;
> +}
> +
> +DEFINE_MACHINE("loongson3-virt", mips_loongson3_virt_machine_init)
> diff --git a/hw/mips/meson.build b/hw/mips/meson.build
> index c98391c..72db43c 100644
> --- a/hw/mips/meson.build
> +++ b/hw/mips/meson.build
> @@ -1,6 +1,7 @@
>   mips_ss = ss.source_set()
>   mips_ss.add(files('addr.c', 'mips_int.c', 'fw_cfg.c'))
>   mips_ss.add(when: 'CONFIG_FULOONG', if_true: files('fuloong2e.c'))
> +mips_ss.add(when: 'CONFIG_LOONGSON3V', if_true: files('loongson3_bootp.c', 'loongson3_virt.c'))
>   mips_ss.add(when: 'CONFIG_JAZZ', if_true: files('jazz.c'))
>   mips_ss.add(when: 'CONFIG_MALTA', if_true: files('gt64xxx_pci.c', 'malta.c'))
>   mips_ss.add(when: 'CONFIG_MIPSSIM', if_true: files('mipssim.c'))
>
Huacai Chen Oct. 11, 2020, 2:53 a.m. UTC | #2
Hi, Philippe,

On Sat, Oct 10, 2020 at 5:09 PM Philippe Mathieu-Daudé <f4bug@amsat.org> wrote:
>
> Hi Huacai,
>
> On 10/7/20 10:39 AM, Huacai Chen wrote:
> > Add Loongson-3 based machine support, it use liointc as the interrupt
> > controler and use GPEX as the pci controller. Currently it can work with
> > both TCG and KVM.
> >
> > As the machine model is not based on any exiting physical hardware, the
> > name of the machine is "loongson3-virt". It may be superseded in future
> > by a real machine model. If this happens, then a regular deprecation
> > procedure shall occur for "loongson3-virt" machine.
> >
> > We now already have a full functional Linux kernel (based on Linux-5.4.x
> > LTS, the kvm host side and guest side have both been upstream for Linux-
> > 5.9, but Linux-5.9 has not been released yet) here:
> >
> > https://github.com/chenhuacai/linux
> >
> > Of course the upstream kernel is also usable (though it is "unstable"
> > now):
> >
> > https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
> >
> > How to use QEMU/Loongson-3?
> > 1, Download kernel source from the above URL;
> > 2, Build a kernel with arch/mips/configs/loongson3_defconfig;
> > 3, Boot a Loongson-3A4000 host with this kernel (for KVM mode);
> > 4, Build QEMU-master with this patchset;
> > 5, modprobe kvm (only necessary for KVM mode);
> > 6, Use QEMU with TCG:
> >         qemu-system-mips64el -M loongson3-virt,accel=tcg -cpu Loongson-3A1000 -kernel <path_to_kernel> -append ...
> >     Use QEMU with KVM:
> >         qemu-system-mips64el -M loongson3-virt,accel=kvm -cpu Loongson-3A4000 -kernel <path_to_kernel> -append ...
> >
> >     The "-cpu" parameter is optional here and QEMU will use the correct type for TCG/KVM automatically.
> >
> > Signed-off-by: Huacai Chen <chenhc@lemote.com>
> > Co-developed-by: Jiaxun Yang <jiaxun.yang@flygoat.com>
> > ---
> >   default-configs/devices/mips64el-softmmu.mak |   1 +
> >   hw/mips/Kconfig                              |  12 +
> >   hw/mips/loongson3_bootp.c                    | 162 +++++++
> >   hw/mips/loongson3_bootp.h                    | 225 ++++++++++
>
> In a previous version I asked if you could split the bootp* files
> (firmware related) in a previous separate patch to ease the review
> of the machine part.
In previous version you told me to split the fw_cfg to a separate
patch, but split the efi-related helpers to seprate files (not to a
patch). But anyway, I will split them to a patch in the next version.

>
> >   hw/mips/loongson3_virt.c                     | 615 +++++++++++++++++++++++++++
> >   hw/mips/meson.build                          |   1 +
> >   6 files changed, 1016 insertions(+)
> [...]
>
> > diff --git a/hw/mips/loongson3_virt.c b/hw/mips/loongson3_virt.c
> > new file mode 100644
> > index 0000000..4e573d6
> > --- /dev/null
> > +++ b/hw/mips/loongson3_virt.c
> > @@ -0,0 +1,615 @@
> > +/*
> > + * Generic Loongson-3 Platform support
> > + *
> > + * Copyright (c) 2017-2020 Huacai Chen (chenhc@lemote.com)
> > + * Copyright (c) 2017-2020 Jiaxun Yang <jiaxun.yang@flygoat.com>
> > + *
> > + * This program is free software: you can redistribute it and/or modify
> > + * it under the terms of the GNU General Public License as published by
> > + * the Free Software Foundation, either version 2 of the License, or
> > + * (at your option) any later version.
> > + *
> > + * This program is distributed in the hope that it will be useful,
> > + * but WITHOUT ANY WARRANTY; without even the implied warranty of
> > + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
> > + * GNU General Public License for more details.
> > + *
> > + * You should have received a copy of the GNU General Public License
> > + * along with this program. If not, see <https://www.gnu.org/licenses/>.
> > + */
> > +
> > +/*
> > + * Generic virtualized PC Platform based on Loongson-3 CPU (MIPS64R2 with
> > + * extensions, 800~2000MHz)
> > + */
> > +
> > +#include "qemu/osdep.h"
> > +#include "qemu-common.h"
> > +#include "qemu/units.h"
> > +#include "qemu/cutils.h"
> > +#include "qapi/error.h"
> > +#include "cpu.h"
> > +#include "elf.h"
> > +#include "kvm_mips.h"
> > +#include "hw/boards.h"
> > +#include "hw/char/serial.h"
> > +#include "hw/mips/mips.h"
> > +#include "hw/mips/cpudevs.h"
> > +#include "hw/mips/fw_cfg.h"
> > +#include "hw/mips/loongson3_bootp.h"
> > +#include "hw/misc/unimp.h"
> > +#include "hw/intc/i8259.h"
> > +#include "hw/loader.h"
> > +#include "hw/isa/superio.h"
> > +#include "hw/pci/msi.h"
> > +#include "hw/pci/pci.h"
> > +#include "hw/pci/pci_host.h"
> > +#include "hw/pci-host/gpex.h"
> > +#include "hw/rtc/mc146818rtc.h"
> > +#include "hw/usb.h"
> > +#include "net/net.h"
> > +#include "exec/address-spaces.h"
> > +#include "sysemu/kvm.h"
> > +#include "sysemu/qtest.h"
> > +#include "sysemu/reset.h"
> > +#include "sysemu/runstate.h"
> > +#include "qemu/log.h"
> > +#include "qemu/error-report.h"
> > +
> > +#define PM_CNTL_MODE          0x10
> > +
> > +#define LOONGSON_MAX_VCPUS      16
> > +
> > +#define LOONGSON3_BIOSNAME "bios_loongson3.bin"
>
> Where is that file?
I don't know the policy of QEMU's binary file, just put that in the
roms directory?

>
> > +
> > +#define UART_IRQ            0
> > +#define RTC_IRQ             1
> > +#define PCIE_IRQ_BASE       2
> > +
> > +const struct MemmapEntry virt_memmap[] = {
> > +    [VIRT_LOWMEM] =      { 0x00000000,    0x10000000 },
> > +    [VIRT_PM] =          { 0x10080000,         0x100 },
> > +    [VIRT_FW_CFG] =      { 0x10080100,         0x100 },
> > +    [VIRT_RTC] =         { 0x10081000,        0x1000 },
> > +    [VIRT_PCIE_PIO] =    { 0x18000000,       0x80000 },
> > +    [VIRT_PCIE_ECAM] =   { 0x1a000000,     0x2000000 },
> > +    [VIRT_BIOS_ROM] =    { 0x1fc00000,      0x200000 },
> > +    [VIRT_UART] =        { 0x1fe001e0,           0x8 },
>
> See below about this mapping.
>
> > +    [VIRT_LIOINTC] =     { 0x3ff01400,          0x64 },
> > +    [VIRT_PCIE_MMIO] =   { 0x40000000,    0x40000000 },
> > +    [VIRT_HIGHMEM] =     { 0x80000000,           0x0 }, /* Variable */
> > +};
> > +
> > +static const struct MemmapEntry loader_memmap[] = {
> > +    [LOADER_KERNEL] =    { 0x00000000,     0x4000000 },
> > +    [LOADER_INITRD] =    { 0x04000000,           0x0 }, /* Variable */
> > +    [LOADER_CMDLINE] =   { 0x0ff00000,      0x100000 },
> > +};
> > +
> > +static const struct MemmapEntry loader_rommap[] = {
> > +    [LOADER_BOOTROM] =   { 0x1fc00000,        0x1000 },
> > +    [LOADER_PARAM] =     { 0x1fc01000,       0x10000 },
> > +};
> > +
> > +static struct _loaderparams {
> > +    uint64_t cpu_freq;
> > +    uint64_t ram_size;
> > +    const char *kernel_cmdline;
> > +    const char *kernel_filename;
> > +    const char *initrd_filename;
> > +    uint64_t kernel_entry;
> > +    uint64_t a0, a1, a2;
> > +} loaderparams;
> > +
> > +static uint64_t loongson3_pm_read(void *opaque, hwaddr addr, unsigned size)
> > +{
> > +    return 0;
> > +}
> > +
> > +static void loongson3_pm_write(void *opaque, hwaddr addr, uint64_t val, unsigned size)
> > +{
> > +    if (addr != PM_CNTL_MODE) {
> > +        return;
> > +    }
> > +
> > +    switch (val) {
> > +    case 0x00:
> > +        qemu_system_reset_request(SHUTDOWN_CAUSE_GUEST_RESET);
> > +        return;
> > +    case 0xff:
> > +        qemu_system_shutdown_request(SHUTDOWN_CAUSE_GUEST_SHUTDOWN);
> > +        return;
> > +    default:
> > +        return;
> > +    }
> > +}
> > +
> > +static const MemoryRegionOps loongson3_pm_ops = {
> > +    .read  = loongson3_pm_read,
> > +    .write = loongson3_pm_write,
> > +    .endianness = DEVICE_NATIVE_ENDIAN,
> > +};
> > +
> > +#define DEF_TCG_FREQ (200 * 1000 * 1000)
> > +#define DEF_KVM_FREQ (1600 * 1000 * 1000)
> > +
> > +static uint64_t get_cpu_freq(void)
> > +{
> > +#ifdef CONFIG_KVM
> > +    int ret;
> > +    uint64_t freq;
> > +    struct kvm_one_reg freq_reg = {
> > +        .id = KVM_REG_MIPS_COUNT_HZ,
> > +        .addr = (uintptr_t)(&freq)
> > +    };
> > +
> > +    if (kvm_enabled()) {
> > +        ret = kvm_vcpu_ioctl(first_cpu, KVM_GET_ONE_REG, &freq_reg);
> > +        if (ret < 0) {
> > +            return DEF_KVM_FREQ;
> > +        }
> > +        return freq * 2;
> > +    } else {
> > +        /*
> > +         * TCG has a default CP0 Timer period 10 ns, which is 100MHz,
> > +         * CPU frequency is defined as double of CP0 timer frequency.
> > +         */
> > +        return DEF_TCG_FREQ;
> > +    }
> > +#else
> > +    return DEF_TCG_FREQ;
> > +#endif
> > +}
> > +
> > +static void init_boot_param(void)
> > +{
> > +    void *p;
> > +    struct boot_params *bp;
> > +
> > +    p = g_malloc0(loader_rommap[LOADER_PARAM].size);
> > +    bp = p;
> > +
> > +    stw_le_p(&bp->efi.smbios.vers, 1);
> > +    init_reset_system(&(bp->reset_system));
> > +    p += ROUND_UP(sizeof(struct boot_params), 64);
> > +    init_loongson_params(&(bp->efi.smbios.lp), p,
> > +                         loaderparams.cpu_freq, loaderparams.ram_size);
> > +
> > +    rom_add_blob_fixed("params_rom", bp,
> > +                       loader_rommap[LOADER_PARAM].size,
> > +                       loader_rommap[LOADER_PARAM].base);
> > +
> > +    g_free(bp);
> > +
> > +    loaderparams.a2 = cpu_mips_phys_to_kseg0(NULL, loader_rommap[LOADER_PARAM].base);
> > +}
> > +
> > +static void init_boot_rom(void)
> > +{
> > +    const unsigned int boot_code[] = {
> > +        0x40086000,   /* mfc0    t0, CP0_STATUS                               */
> > +        0x240900E4,   /* li      t1, 0xe4         #set kx, sx, ux, erl        */
> > +        0x01094025,   /* or      t0, t0, t1                                   */
> > +        0x3C090040,   /* lui     t1, 0x40         #set bev                    */
> > +        0x01094025,   /* or      t0, t0, t1                                   */
> > +        0x40886000,   /* mtc0    t0, CP0_STATUS                               */
> > +        0x00000000,
> > +        0x40806800,   /* mtc0    zero, CP0_CAUSE                              */
> > +        0x00000000,
> > +        0x400A7801,   /* mfc0    t2, $15, 1                                   */
> > +        0x314A00FF,   /* andi    t2, 0x0ff                                    */
> > +        0x3C089000,   /* dli     t0, 0x900000003ff01000                       */
> > +        0x00084438,
> > +        0x35083FF0,
> > +        0x00084438,
> > +        0x35081000,
> > +        0x314B0003,   /* andi    t3, t2, 0x3      #local cpuid                */
> > +        0x000B5A00,   /* sll     t3, 8                                        */
> > +        0x010B4025,   /* or      t0, t0, t3                                   */
> > +        0x314C000C,   /* andi    t4, t2, 0xc      #node id                    */
> > +        0x000C62BC,   /* dsll    t4, 42                                       */
> > +        0x010C4025,   /* or      t0, t0, t4                                   */
> > +                      /* WaitForInit:                                         */
> > +        0xDD020020,   /* ld      v0, FN_OFF(t0)   #FN_OFF 0x020               */
> > +        0x1040FFFE,   /* beqz    v0, WaitForInit                              */
> > +        0x00000000,   /* nop                                                  */
> > +        0xDD1D0028,   /* ld      sp, SP_OFF(t0)   #FN_OFF 0x028               */
> > +        0xDD1C0030,   /* ld      gp, GP_OFF(t0)   #FN_OFF 0x030               */
> > +        0xDD050038,   /* ld      a1, A1_OFF(t0)   #FN_OFF 0x038               */
> > +        0x00400008,   /* jr      v0               #byebye                     */
> > +        0x00000000,   /* nop                                                  */
> > +        0x1000FFFF,   /* 1:  b   1b                                           */
> > +        0x00000000,   /* nop                                                  */
> > +
> > +                      /* Reset                                                */
> > +        0x3C0C9000,   /* dli     t0, 0x9000000010080010                       */
> > +        0x358C0000,
> > +        0x000C6438,
> > +        0x358C1008,
> > +        0x000C6438,
> > +        0x358C0010,
> > +        0x240D0000,   /* li      t1, 0x00                                     */
> > +        0xA18D0000,   /* sb      t1, (t0)                                     */
> > +        0x1000FFFF,   /* 1:  b   1b                                           */
> > +        0x00000000,   /* nop                                                  */
> > +
> > +                      /* Shutdown                                             */
> > +        0x3C0C9000,   /* dli     t0, 0x9000000010080010                       */
> > +        0x358C0000,
> > +        0x000C6438,
> > +        0x358C1008,
> > +        0x000C6438,
> > +        0x358C0010,
> > +        0x240D00FF,   /* li      t1, 0xff                                     */
> > +        0xA18D0000,   /* sb      t1, (t0)                                     */
> > +        0x1000FFFF,   /* 1:  b   1b                                           */
> > +        0x00000000    /* nop                                                  */
> > +    };
> > +
> > +    rom_add_blob_fixed("boot_rom", boot_code, sizeof(boot_code),
> > +                        loader_rommap[LOADER_BOOTROM].base);
> > +}
> > +
> > +static void fw_cfg_boot_set(void *opaque, const char *boot_device,
> > +                            Error **errp)
> > +{
> > +    fw_cfg_modify_i16(opaque, FW_CFG_BOOT_DEVICE, boot_device[0]);
> > +}
> > +
> > +static void fw_conf_init(unsigned long ram_size)
> > +{
> > +    FWCfgState *fw_cfg;
> > +    hwaddr cfg_addr = virt_memmap[VIRT_FW_CFG].base;
> > +
> > +    fw_cfg = fw_cfg_init_mem_wide(cfg_addr, cfg_addr + 8, 8, 0, NULL);
> > +    fw_cfg_add_i16(fw_cfg, FW_CFG_NB_CPUS, (uint16_t)current_machine->smp.cpus);
> > +    fw_cfg_add_i16(fw_cfg, FW_CFG_MAX_CPUS, (uint16_t)current_machine->smp.max_cpus);
> > +    fw_cfg_add_i64(fw_cfg, FW_CFG_RAM_SIZE, (uint64_t)ram_size);
> > +    fw_cfg_add_i32(fw_cfg, FW_CFG_MACHINE_VERSION, 1);
> > +    fw_cfg_add_i64(fw_cfg, FW_CFG_CPU_FREQ, get_cpu_freq());
> > +    qemu_register_boot_set(fw_cfg_boot_set, fw_cfg);
> > +}
> > +
> > +static int set_prom_cmdline(ram_addr_t initrd_offset, long initrd_size)
> > +{
> > +    hwaddr cmdline_vaddr;
> > +    char memenv[32];
> > +    char highmemenv[32];
> > +    void *cmdline_buf;
> > +    unsigned int *parg_env;
> > +    int ret = 0;
> > +
> > +    /* Allocate cmdline_buf for command line. */
> > +    cmdline_buf = g_malloc0(loader_memmap[LOADER_CMDLINE].size);
> > +    cmdline_vaddr = cpu_mips_phys_to_kseg0(NULL,
> > +                                           loader_memmap[LOADER_CMDLINE].base);
> > +
> > +    /*
> > +     * Layout of cmdline_buf looks like this:
> > +     * argv[0], argv[1], 0, env[0], env[1], ... env[i], 0,
> > +     * argv[0]'s data, argv[1]'s data, env[0]'data, ..., env[i]'s data, 0
> > +     */
> > +    parg_env = (void *)cmdline_buf;
> > +
> > +    ret = (3 + 1) * 4;
> > +    *parg_env++ = cmdline_vaddr + ret;
> > +    ret += (1 + snprintf(cmdline_buf + ret, 256 - ret, "g"));
> > +
> > +    /* argv1 */
> > +    *parg_env++ = cmdline_vaddr + ret;
> > +    if (initrd_size > 0)
> > +        ret += (1 + snprintf(cmdline_buf + ret, 256 - ret,
> > +                "rd_start=0x" TARGET_FMT_lx " rd_size=%li %s",
> > +                cpu_mips_phys_to_kseg0(NULL, initrd_offset),
> > +                initrd_size, loaderparams.kernel_cmdline));
> > +    else
> > +        ret += (1 + snprintf(cmdline_buf + ret, 256 - ret, "%s",
> > +                loaderparams.kernel_cmdline));
> > +
> > +    /* argv2 */
> > +    *parg_env++ = cmdline_vaddr + 4 * ret;
> > +
> > +    /* env */
> > +    sprintf(memenv, "%d", 256);
> > +    sprintf(highmemenv, "%ld", (unsigned long)(loaderparams.ram_size / MiB) - 256);
> > +
> > +    rom_add_blob_fixed("cmdline", cmdline_buf,
> > +                       loader_memmap[LOADER_CMDLINE].size,
> > +                       loader_memmap[LOADER_CMDLINE].base);
> > +
> > +    g_free(cmdline_buf);
> > +
> > +    loaderparams.a0 = 2;
> > +    loaderparams.a1 = cmdline_vaddr;
> > +
> > +    return 0;
> > +}
> > +
> > +static uint64_t load_kernel(CPUMIPSState *env)
> > +{
> > +    long kernel_size;
> > +    ram_addr_t initrd_offset;
> > +    uint64_t kernel_entry, kernel_low, kernel_high, initrd_size;
> > +
> > +    kernel_size = load_elf(loaderparams.kernel_filename, NULL,
> > +                           cpu_mips_kseg0_to_phys, NULL,
> > +                           (uint64_t *)&kernel_entry,
> > +                           (uint64_t *)&kernel_low, (uint64_t *)&kernel_high,
> > +                           NULL, 0, EM_MIPS, 1, 0);
> > +    if (kernel_size < 0) {
> > +        error_report("could not load kernel '%s': %s",
> > +                     loaderparams.kernel_filename,
> > +                     load_elf_strerror(kernel_size));
> > +        exit(1);
> > +    }
> > +
> > +    /* load initrd */
> > +    initrd_size = 0;
> > +    initrd_offset = 0;
> > +    if (loaderparams.initrd_filename) {
> > +        initrd_size = get_image_size(loaderparams.initrd_filename);
> > +        if (initrd_size > 0) {
> > +            initrd_offset = (kernel_high + ~INITRD_PAGE_MASK) &
> > +                            INITRD_PAGE_MASK;
> > +            initrd_offset = MAX(initrd_offset,
> > +                                loader_memmap[LOADER_INITRD].base);
> > +
> > +            if (initrd_offset + initrd_size > ram_size) {
> > +                error_report("memory too small for initial ram disk '%s'",
> > +                             loaderparams.initrd_filename);
> > +                exit(1);
> > +            }
> > +
> > +            initrd_size = load_image_targphys(loaderparams.initrd_filename,
> > +                                              initrd_offset,
> > +                                              ram_size - initrd_offset);
> > +        }
> > +
> > +        if (initrd_size == (target_ulong) -1) {
> > +            error_report("could not load initial ram disk '%s'",
> > +                         loaderparams.initrd_filename);
> > +            exit(1);
> > +        }
> > +    }
> > +
> > +    /* Setup prom cmdline. */
> > +    set_prom_cmdline(initrd_offset, initrd_size);
> > +
> > +    return kernel_entry;
> > +}
> > +
> > +static void main_cpu_reset(void *opaque)
> > +{
> > +    MIPSCPU *cpu = opaque;
> > +    CPUMIPSState *env = &cpu->env;
> > +
> > +    cpu_reset(CPU(cpu));
> > +
> > +    /* Loongson-3 reset stuff */
> > +    if (loaderparams.kernel_filename) {
> > +        if (cpu == MIPS_CPU(first_cpu)) {
> > +            env->active_tc.gpr[4] = loaderparams.a0;
> > +            env->active_tc.gpr[5] = loaderparams.a1;
> > +            env->active_tc.gpr[6] = loaderparams.a2;
> > +            env->active_tc.PC = loaderparams.kernel_entry;
> > +        }
> > +        env->CP0_Status &= ~((1 << CP0St_BEV) | (1 << CP0St_ERL));
> > +    }
> > +}
> > +
> > +static inline void loongson3_virt_devices_init(MachineState *machine, DeviceState *pic)
> > +{
> > +    int i;
> > +    qemu_irq irq;
> > +    PCIBus *pci_bus;
> > +    DeviceState *dev;
> > +    MemoryRegion *pio_alias;
> > +    MemoryRegion *mmio_alias, *mmio_reg;
> > +    MemoryRegion *ecam_alias, *ecam_reg;
> > +
> > +    dev = qdev_new(TYPE_GPEX_HOST);
> > +    sysbus_realize_and_unref(SYS_BUS_DEVICE(dev), &error_fatal);
> > +    pci_bus = PCI_HOST_BRIDGE(dev)->bus;
> > +
> > +    ecam_alias = g_new0(MemoryRegion, 1);
> > +    ecam_reg = sysbus_mmio_get_region(SYS_BUS_DEVICE(dev), 0);
> > +    memory_region_init_alias(ecam_alias, OBJECT(dev), "pcie-ecam",
> > +                             ecam_reg, 0, virt_memmap[VIRT_PCIE_ECAM].size);
> > +    memory_region_add_subregion(get_system_memory(),
> > +                                virt_memmap[VIRT_PCIE_ECAM].base, ecam_alias);
> > +
> > +    mmio_alias = g_new0(MemoryRegion, 1);
> > +    mmio_reg = sysbus_mmio_get_region(SYS_BUS_DEVICE(dev), 1);
> > +    memory_region_init_alias(mmio_alias, OBJECT(dev), "pcie-mmio",
> > +                             mmio_reg, virt_memmap[VIRT_PCIE_MMIO].base,
> > +                             virt_memmap[VIRT_PCIE_MMIO].size);
> > +    memory_region_add_subregion(get_system_memory(),
> > +                                virt_memmap[VIRT_PCIE_MMIO].base, mmio_alias);
> > +
> > +    pio_alias = g_new0(MemoryRegion, 1);
> > +    memory_region_init_alias(pio_alias, OBJECT(dev), "pcie-pio",
> > +                             get_system_io(), 0, virt_memmap[VIRT_PCIE_PIO].size);
> > +    memory_region_add_subregion(get_system_memory(),
> > +                                virt_memmap[VIRT_PCIE_PIO].base, pio_alias);
> > +    sysbus_mmio_map(SYS_BUS_DEVICE(dev), 2, virt_memmap[VIRT_PCIE_PIO].base);
> > +
> > +    for (i = 0; i < GPEX_NUM_IRQS; i++) {
> > +        irq = qdev_get_gpio_in(pic, PCIE_IRQ_BASE + i);
> > +        sysbus_connect_irq(SYS_BUS_DEVICE(dev), i, irq);
> > +        gpex_set_irq_num(GPEX_HOST(dev), i, PCIE_IRQ_BASE + i);
> > +    }
> > +
> > +    pci_vga_init(pci_bus);
> > +
> > +    if (defaults_enabled()) {
> > +        pci_create_simple(pci_bus, -1, "pci-ohci");
> > +        usb_create_simple(usb_bus_find(-1), "usb-kbd");
> > +        usb_create_simple(usb_bus_find(-1), "usb-tablet");
> > +    }
> > +
> > +    for (i = 0; i < nb_nics; i++) {
> > +        NICInfo *nd = &nd_table[i];
> > +
> > +        if (!nd->model) {
> > +            nd->model = g_strdup("virtio");
> > +        }
> > +
> > +        pci_nic_init_nofail(nd, pci_bus, nd->model, NULL);
> > +    }
> > +}
> > +
> > +static void mips_loongson3_virt_init(MachineState *machine)
> > +{
> > +    int i;
> > +    long bios_size;
> > +    MIPSCPU *cpu;
> > +    CPUMIPSState *env;
> > +    DeviceState *liointc;
> > +    char *filename;
> > +    const char *kernel_cmdline = machine->kernel_cmdline;
> > +    const char *kernel_filename = machine->kernel_filename;
> > +    const char *initrd_filename = machine->initrd_filename;
> > +    ram_addr_t ram_size = machine->ram_size;
> > +    MemoryRegion *address_space_mem = get_system_memory();
> > +    MemoryRegion *ram = g_new(MemoryRegion, 1);
> > +    MemoryRegion *bios = g_new(MemoryRegion, 1);
> > +    MemoryRegion *iomem = g_new(MemoryRegion, 1);
> > +
> > +    /* TODO: TCG will support all CPU types */
> > +    if (!kvm_enabled()) {
> > +        if (!machine->cpu_type) {
> > +            machine->cpu_type = MIPS_CPU_TYPE_NAME("Loongson-3A1000");
> > +        }
> > +        if (!strstr(machine->cpu_type, "Loongson-3A1000")) {
> > +            error_report("Loongson-3/TCG needs cpu type Loongson-3A1000");
> > +            exit(1);
> > +        }
>
> IIUC here you need to check machine->smp.cpus is 4 or 8 for the 3A1000.
> It would be easier if you model this as a qdev SoC, and this model
> cares to create the 4/8 cores (QEMU MIPSCPU).
>
> You defined max_cpu = LOONGSON_MAX_VCPUS = 16, this seems an impossible
> configuration for the 3A1000.
There are 4 cores in a SoC, but Loongson-3 support multi-sockets, more
than 4 vcpus will be treated as multi-sockets automatically in guests.
And current linux kernel also handle the case that only boot part of 4
cores in a socket.

>
> > +    } else {
> > +        if (!machine->cpu_type) {
> > +            machine->cpu_type = MIPS_CPU_TYPE_NAME("Loongson-3A4000");
> > +        }
> > +        if (!strstr(machine->cpu_type, "Loongson-3A4000")) {
> > +            error_report("Loongson-3/KVM needs cpu type Loongson-3A4000");
> > +            exit(1);
> > +        }
>
> Similar comment, as the 3A4000 is also a quad-core.
>
> > +    }
> > +
> > +    if (ram_size < 512 * MiB) {
> > +        error_report("Loongson-3 machine needs at least 512MB memory");
> > +        exit(1);
> > +    }
> > +
> > +    /*
> > +     * The whole MMIO range among configure registers doesn't generate
> > +     * exception when accessing invalid memory. Create an unimplememted
> > +     * device to emulate this feature.
> > +     */
> > +    create_unimplemented_device("fallback", 0x10000000, 0x30000000);
>
> The secondary crosswise switch description is hard to follow:
>
> * 2.4 Address routing distribution and configuration
>
> According  to  the  default  register  configuration,  CPU [...]
> 0x10000000-0x1fffffff  of  CPU  (256M)  is  mapped  to
> 0x10000000-0x1fffffff  of  PCI,  and  0x80000000  of  PCIDMA.
> In addition, when read access to illegal addresses occurs due to CPU
> guess execution, all 8 address Windows fail to hit, ?
>
> Table 2-9 XBAR level 2 default address configuration
>                    base                    high                     owner
> 0 x0000_0000_1000_0000  0 x0000_0000_2000_0000  Low speed I/O (PCI, etc)
>
> * 14.4 Secondary cross-switch address window
>
> After the address window is configured, the system address
> 0x0000_2000_0000 is added-- 0x0000_2FFFF_FFFF  maps  to
> 0x0000_0000_0000  -- 0x0000_0FFF_FFFF  of  memory  controller 0.An
> access to 0x0000_2000_0000 at this time will result in the original
> enabledThe value stored at address 0x0000_0000_0000.
>
> But see:
>
> * 14.6.3 Low speed device address window
>
> Here are defined the peripherals in the 0x1c00_0000-0x1ff0_ffff range.
>
> * 15.1 System memory space
>
> IO device, 0x1000_0000 --  0x1FFF_FFFF
>
> * 16 Memory allocation for system X
>
> ... divide  the  256M  PCI  space  (0x10000000~0x20000000)  into  two
> parts:  0x10000000~0x17ffffff for mem space and 0x18000000~0x20000000
> for IO space.
>
> I still don't understand what is in the 0x20000000-0x30000000 range.
Loongson's user manual is a little confusing, as a native Chinese I
also feel uncomfortable sometimes. :)
Generally speaking, Loongson-3's address space is configurable via
address windows, and the recommended configurations is like this:
0x00000000-0x10000000   Low RAM
0x10000000-0x40000000   ROM and MMIO Registers (such as BIOS_ROM at
0x1fc00000, UART at 0x1fe001e0, LIOINTC at 0x3ff00140)
0x40000000-0x80000000  PCI MEM
0x80000000-TOM             High RAM

PCI DMA of 0x10000000-0x1fffffff is a legacy region from
Loongson-2E/2F, and be cancelled in Loongson-3's configuration.
In real hardware, there should be a default "big enough" address
window to catch illegal address, return 0 for read access.
Yes, there is "nothing" in 0x20000000-0x30000000, because it is
undocumented which means "reserved for internal usage".
>
> > +
> > +    liointc = qdev_new("loongson.liointc");
> > +    sysbus_realize_and_unref(SYS_BUS_DEVICE(liointc), &error_fatal);
> > +
> > +    sysbus_mmio_map(SYS_BUS_DEVICE(liointc), 0, virt_memmap[VIRT_LIOINTC].base);
> > +
> > +    for (i = 0; i < machine->smp.cpus; i++) {
> > +        int ip;
> > +
> > +        /* init CPUs */
> > +        cpu = MIPS_CPU(cpu_create(machine->cpu_type));
> > +
> > +        /* Init internal devices */
> > +        cpu_mips_irq_init_cpu(cpu);
> > +        cpu_mips_clock_init(cpu);
> > +        qemu_register_reset(main_cpu_reset, cpu);
> > +
> > +        if (i >= 4) {
> > +            continue; /* Only node-0 can be connected to LIOINTC */
> > +        }
> > +
> > +        for (ip = 0; ip < 4 ; ip++) {
> > +            int pin = i * 4 + ip;
> > +            sysbus_connect_irq(SYS_BUS_DEVICE(liointc),
> > +                               pin, cpu->env.irq[ip + 2]);
> > +        }
> > +    }
> > +    env = &MIPS_CPU(first_cpu)->env;
> > +
> > +    /* Allocate RAM/BIOS, 0x00000000~0x10000000 is alias of 0x80000000~0x90000000 */
> > +    memory_region_init_rom(bios, NULL, "loongson3.bios",
> > +                           virt_memmap[VIRT_BIOS_ROM].size, &error_fatal);
> > +    memory_region_init_alias(ram, NULL, "loongson3.lowmem",
> > +                           machine->ram, 0, virt_memmap[VIRT_LOWMEM].size);
> > +    memory_region_init_io(iomem, NULL, &loongson3_pm_ops,
> > +                           NULL, "loongson3_pm", virt_memmap[VIRT_PM].size);
> > +
> > +    memory_region_add_subregion(address_space_mem,
> > +                      virt_memmap[VIRT_LOWMEM].base, ram);
> > +    memory_region_add_subregion(address_space_mem,
> > +                      virt_memmap[VIRT_BIOS_ROM].base, bios);
> > +    memory_region_add_subregion(address_space_mem,
> > +                      virt_memmap[VIRT_HIGHMEM].base, machine->ram);
> > +    memory_region_add_subregion(address_space_mem,
> > +                      virt_memmap[VIRT_PM].base, iomem);
> > +
> > +    /*
> > +     * We do not support flash operation, just loading bios.bin as raw BIOS.
> > +     * Please use -L to set the BIOS path and -bios to set bios name.
> > +     */
> > +
> > +    if (kernel_filename) {
> > +        loaderparams.cpu_freq = get_cpu_freq();
> > +        loaderparams.ram_size = ram_size;
> > +        loaderparams.kernel_filename = kernel_filename;
> > +        loaderparams.kernel_cmdline = kernel_cmdline;
> > +        loaderparams.initrd_filename = initrd_filename;
> > +        loaderparams.kernel_entry = load_kernel(env);
> > +
> > +        init_boot_rom();
> > +        init_boot_param();
> > +    } else {
> > +        if (bios_name == NULL) {
> > +                bios_name = LOONGSON3_BIOSNAME;
> > +        }
> > +        filename = qemu_find_file(QEMU_FILE_TYPE_BIOS, bios_name);
> > +        if (filename) {
> > +            bios_size = load_image_targphys(filename,
> > +                                            virt_memmap[VIRT_BIOS_ROM].base,
> > +                                            virt_memmap[VIRT_BIOS_ROM].size);
> > +            g_free(filename);
> > +        } else {
> > +            bios_size = -1;
> > +        }
> > +
> > +        if ((bios_size < 0 || bios_size > virt_memmap[VIRT_BIOS_ROM].size) &&
> > +            !kernel_filename && !qtest_enabled()) {
> > +            error_report("Could not load MIPS bios '%s'", bios_name);
> > +            exit(1);
> > +        }
> > +
> > +        fw_conf_init(ram_size);
> > +    }
> > +
> > +    msi_nonbroken = true;
> > +    loongson3_virt_devices_init(machine, liointc);
> > +
> > +    sysbus_create_simple("goldfish_rtc", virt_memmap[VIRT_RTC].base,
> > +                         qdev_get_gpio_in(liointc, RTC_IRQ));
> > +
> > +    serial_mm_init(address_space_mem, virt_memmap[VIRT_UART].base, 0,
> > +                   qdev_get_gpio_in(liointc, UART_IRQ), 115200, serial_hd(0),
> > +                   DEVICE_NATIVE_ENDIAN);
>
> You need to split the SoC part from the machine part.
What do you mean? UART is SoC part and put it near LIOINTC?

>
> > +}
> > +
> > +static void mips_loongson3_virt_machine_init(MachineClass *mc)
> > +{
> > +    mc->desc = "Loongson-3 Virtualization Platform";
> > +    mc->init = mips_loongson3_virt_init;
> > +    mc->block_default_type = IF_IDE;
>
> Don't you need min_cpus = 4?
I think this is needn't.

>
> > +    mc->max_cpus = LOONGSON_MAX_VCPUS;
> > +    mc->default_ram_id = "loongson3.highram";
> > +    mc->default_ram_size = 1600 * MiB;
> > +    mc->kvm_type = mips_kvm_type;
> > +    mc->minimum_page_bits = 14;
> > +}
> > +
> > +DEFINE_MACHINE("loongson3-virt", mips_loongson3_virt_machine_init)
> > diff --git a/hw/mips/meson.build b/hw/mips/meson.build
> > index c98391c..72db43c 100644
> > --- a/hw/mips/meson.build
> > +++ b/hw/mips/meson.build
> > @@ -1,6 +1,7 @@
> >   mips_ss = ss.source_set()
> >   mips_ss.add(files('addr.c', 'mips_int.c', 'fw_cfg.c'))
> >   mips_ss.add(when: 'CONFIG_FULOONG', if_true: files('fuloong2e.c'))
> > +mips_ss.add(when: 'CONFIG_LOONGSON3V', if_true: files('loongson3_bootp.c', 'loongson3_virt.c'))
> >   mips_ss.add(when: 'CONFIG_JAZZ', if_true: files('jazz.c'))
> >   mips_ss.add(when: 'CONFIG_MALTA', if_true: files('gt64xxx_pci.c', 'malta.c'))
> >   mips_ss.add(when: 'CONFIG_MIPSSIM', if_true: files('mipssim.c'))
> >
Huacai
Philippe Mathieu-Daudé Oct. 12, 2020, 8:12 a.m. UTC | #3
On 10/11/20 4:53 AM, Huacai Chen wrote:
> Hi, Philippe,
> 
> On Sat, Oct 10, 2020 at 5:09 PM Philippe Mathieu-Daudé <f4bug@amsat.org> wrote:
>>
>> Hi Huacai,
>>
>> On 10/7/20 10:39 AM, Huacai Chen wrote:
>>> Add Loongson-3 based machine support, it use liointc as the interrupt
>>> controler and use GPEX as the pci controller. Currently it can work with
>>> both TCG and KVM.
>>>
>>> As the machine model is not based on any exiting physical hardware, the
>>> name of the machine is "loongson3-virt". It may be superseded in future
>>> by a real machine model. If this happens, then a regular deprecation
>>> procedure shall occur for "loongson3-virt" machine.
>>>
>>> We now already have a full functional Linux kernel (based on Linux-5.4.x
>>> LTS, the kvm host side and guest side have both been upstream for Linux-
>>> 5.9, but Linux-5.9 has not been released yet) here:
>>>
>>> https://github.com/chenhuacai/linux
>>>
>>> Of course the upstream kernel is also usable (though it is "unstable"
>>> now):
>>>
>>> https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
>>>
>>> How to use QEMU/Loongson-3?
>>> 1, Download kernel source from the above URL;
>>> 2, Build a kernel with arch/mips/configs/loongson3_defconfig;
>>> 3, Boot a Loongson-3A4000 host with this kernel (for KVM mode);
>>> 4, Build QEMU-master with this patchset;
>>> 5, modprobe kvm (only necessary for KVM mode);
>>> 6, Use QEMU with TCG:
>>>          qemu-system-mips64el -M loongson3-virt,accel=tcg -cpu Loongson-3A1000 -kernel <path_to_kernel> -append ...
>>>      Use QEMU with KVM:
>>>          qemu-system-mips64el -M loongson3-virt,accel=kvm -cpu Loongson-3A4000 -kernel <path_to_kernel> -append ...
>>>
>>>      The "-cpu" parameter is optional here and QEMU will use the correct type for TCG/KVM automatically.
>>>
>>> Signed-off-by: Huacai Chen <chenhc@lemote.com>
>>> Co-developed-by: Jiaxun Yang <jiaxun.yang@flygoat.com>
>>> ---
>>>    default-configs/devices/mips64el-softmmu.mak |   1 +
>>>    hw/mips/Kconfig                              |  12 +
>>>    hw/mips/loongson3_bootp.c                    | 162 +++++++
>>>    hw/mips/loongson3_bootp.h                    | 225 ++++++++++
>>
>> In a previous version I asked if you could split the bootp* files
>> (firmware related) in a previous separate patch to ease the review
>> of the machine part.
 >
> In previous version you told me to split the fw_cfg to a separate
> patch, but split the efi-related helpers to seprate files (not to a
> patch). But anyway, I will split them to a patch in the next version.

Sorry if I wasn't clear enough. It is very hard to review a patch
of more than 1000 lines of C code without loosing focus or missing
problems. It explains why big patches might stay unreviewed on the
list. If you can split in smaller logical units, it will be very
helpful.

Peter Maydell rule of thumb is to keep patch below 200 lines.
This is a good limit.

> 
>>
>>>    hw/mips/loongson3_virt.c                     | 615 +++++++++++++++++++++++++++
>>>    hw/mips/meson.build                          |   1 +
>>>    6 files changed, 1016 insertions(+)
>> [...]
>>
>>> diff --git a/hw/mips/loongson3_virt.c b/hw/mips/loongson3_virt.c
>>> new file mode 100644
>>> index 0000000..4e573d6
>>> --- /dev/null
>>> +++ b/hw/mips/loongson3_virt.c
>>> @@ -0,0 +1,615 @@
>>> +/*
>>> + * Generic Loongson-3 Platform support
>>> + *
>>> + * Copyright (c) 2017-2020 Huacai Chen (chenhc@lemote.com)
>>> + * Copyright (c) 2017-2020 Jiaxun Yang <jiaxun.yang@flygoat.com>
>>> + *
>>> + * This program is free software: you can redistribute it and/or modify
>>> + * it under the terms of the GNU General Public License as published by
>>> + * the Free Software Foundation, either version 2 of the License, or
>>> + * (at your option) any later version.
>>> + *
>>> + * This program is distributed in the hope that it will be useful,
>>> + * but WITHOUT ANY WARRANTY; without even the implied warranty of
>>> + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
>>> + * GNU General Public License for more details.
>>> + *
>>> + * You should have received a copy of the GNU General Public License
>>> + * along with this program. If not, see <https://www.gnu.org/licenses/>.
>>> + */
>>> +
>>> +/*
>>> + * Generic virtualized PC Platform based on Loongson-3 CPU (MIPS64R2 with
>>> + * extensions, 800~2000MHz)
>>> + */
>>> +
>>> +#include "qemu/osdep.h"
>>> +#include "qemu-common.h"
>>> +#include "qemu/units.h"
>>> +#include "qemu/cutils.h"
>>> +#include "qapi/error.h"
>>> +#include "cpu.h"
>>> +#include "elf.h"
>>> +#include "kvm_mips.h"
>>> +#include "hw/boards.h"
>>> +#include "hw/char/serial.h"
>>> +#include "hw/mips/mips.h"
>>> +#include "hw/mips/cpudevs.h"
>>> +#include "hw/mips/fw_cfg.h"
>>> +#include "hw/mips/loongson3_bootp.h"
>>> +#include "hw/misc/unimp.h"
>>> +#include "hw/intc/i8259.h"
>>> +#include "hw/loader.h"
>>> +#include "hw/isa/superio.h"
>>> +#include "hw/pci/msi.h"
>>> +#include "hw/pci/pci.h"
>>> +#include "hw/pci/pci_host.h"
>>> +#include "hw/pci-host/gpex.h"
>>> +#include "hw/rtc/mc146818rtc.h"
>>> +#include "hw/usb.h"
>>> +#include "net/net.h"
>>> +#include "exec/address-spaces.h"
>>> +#include "sysemu/kvm.h"
>>> +#include "sysemu/qtest.h"
>>> +#include "sysemu/reset.h"
>>> +#include "sysemu/runstate.h"
>>> +#include "qemu/log.h"
>>> +#include "qemu/error-report.h"
>>> +
>>> +#define PM_CNTL_MODE          0x10
>>> +
>>> +#define LOONGSON_MAX_VCPUS      16
>>> +
>>> +#define LOONGSON3_BIOSNAME "bios_loongson3.bin"
>>
>> Where is that file?
 >
> I don't know the policy of QEMU's binary file, just put that in the
> roms directory?

If this is a closed source binary, we reference the URL where it can
be downloaded accepting eventual EULA.
If it is open source, the project is added as submodule. QEMU then
provides a link to how to build the firmware, or if there is no such
documentation, buildsys machinery is added to QEMU to build to it
(see roms/Makefile).

> 
>>
>>> +
>>> +#define UART_IRQ            0
>>> +#define RTC_IRQ             1
>>> +#define PCIE_IRQ_BASE       2
>>> +
>>> +const struct MemmapEntry virt_memmap[] = {
>>> +    [VIRT_LOWMEM] =      { 0x00000000,    0x10000000 },
>>> +    [VIRT_PM] =          { 0x10080000,         0x100 },
>>> +    [VIRT_FW_CFG] =      { 0x10080100,         0x100 },
>>> +    [VIRT_RTC] =         { 0x10081000,        0x1000 },
>>> +    [VIRT_PCIE_PIO] =    { 0x18000000,       0x80000 },
>>> +    [VIRT_PCIE_ECAM] =   { 0x1a000000,     0x2000000 },
>>> +    [VIRT_BIOS_ROM] =    { 0x1fc00000,      0x200000 },
>>> +    [VIRT_UART] =        { 0x1fe001e0,           0x8 },
>>
>> See below about this mapping.
>>
>>> +    [VIRT_LIOINTC] =     { 0x3ff01400,          0x64 },
>>> +    [VIRT_PCIE_MMIO] =   { 0x40000000,    0x40000000 },
>>> +    [VIRT_HIGHMEM] =     { 0x80000000,           0x0 }, /* Variable */
>>> +};
>>> +
>>> +static const struct MemmapEntry loader_memmap[] = {
>>> +    [LOADER_KERNEL] =    { 0x00000000,     0x4000000 },
>>> +    [LOADER_INITRD] =    { 0x04000000,           0x0 }, /* Variable */
>>> +    [LOADER_CMDLINE] =   { 0x0ff00000,      0x100000 },
>>> +};
>>> +
>>> +static const struct MemmapEntry loader_rommap[] = {
>>> +    [LOADER_BOOTROM] =   { 0x1fc00000,        0x1000 },
>>> +    [LOADER_PARAM] =     { 0x1fc01000,       0x10000 },
>>> +};
>>> +
>>> +static struct _loaderparams {
>>> +    uint64_t cpu_freq;
>>> +    uint64_t ram_size;
>>> +    const char *kernel_cmdline;
>>> +    const char *kernel_filename;
>>> +    const char *initrd_filename;
>>> +    uint64_t kernel_entry;
>>> +    uint64_t a0, a1, a2;
>>> +} loaderparams;
>>> +
>>> +static uint64_t loongson3_pm_read(void *opaque, hwaddr addr, unsigned size)
>>> +{
>>> +    return 0;
>>> +}
>>> +
>>> +static void loongson3_pm_write(void *opaque, hwaddr addr, uint64_t val, unsigned size)
>>> +{
>>> +    if (addr != PM_CNTL_MODE) {
>>> +        return;
>>> +    }
>>> +
>>> +    switch (val) {
>>> +    case 0x00:
>>> +        qemu_system_reset_request(SHUTDOWN_CAUSE_GUEST_RESET);
>>> +        return;
>>> +    case 0xff:
>>> +        qemu_system_shutdown_request(SHUTDOWN_CAUSE_GUEST_SHUTDOWN);
>>> +        return;
>>> +    default:
>>> +        return;
>>> +    }
>>> +}
>>> +
>>> +static const MemoryRegionOps loongson3_pm_ops = {
>>> +    .read  = loongson3_pm_read,
>>> +    .write = loongson3_pm_write,
>>> +    .endianness = DEVICE_NATIVE_ENDIAN,
>>> +};
>>> +
>>> +#define DEF_TCG_FREQ (200 * 1000 * 1000)
>>> +#define DEF_KVM_FREQ (1600 * 1000 * 1000)
>>> +
>>> +static uint64_t get_cpu_freq(void)
>>> +{
>>> +#ifdef CONFIG_KVM
>>> +    int ret;
>>> +    uint64_t freq;
>>> +    struct kvm_one_reg freq_reg = {
>>> +        .id = KVM_REG_MIPS_COUNT_HZ,
>>> +        .addr = (uintptr_t)(&freq)
>>> +    };
>>> +
>>> +    if (kvm_enabled()) {
>>> +        ret = kvm_vcpu_ioctl(first_cpu, KVM_GET_ONE_REG, &freq_reg);
>>> +        if (ret < 0) {
>>> +            return DEF_KVM_FREQ;
>>> +        }
>>> +        return freq * 2;
>>> +    } else {
>>> +        /*
>>> +         * TCG has a default CP0 Timer period 10 ns, which is 100MHz,
>>> +         * CPU frequency is defined as double of CP0 timer frequency.
>>> +         */
>>> +        return DEF_TCG_FREQ;
>>> +    }
>>> +#else
>>> +    return DEF_TCG_FREQ;
>>> +#endif
>>> +}
>>> +
>>> +static void init_boot_param(void)
>>> +{
>>> +    void *p;
>>> +    struct boot_params *bp;
>>> +
>>> +    p = g_malloc0(loader_rommap[LOADER_PARAM].size);
>>> +    bp = p;
>>> +
>>> +    stw_le_p(&bp->efi.smbios.vers, 1);
>>> +    init_reset_system(&(bp->reset_system));
>>> +    p += ROUND_UP(sizeof(struct boot_params), 64);
>>> +    init_loongson_params(&(bp->efi.smbios.lp), p,
>>> +                         loaderparams.cpu_freq, loaderparams.ram_size);
>>> +
>>> +    rom_add_blob_fixed("params_rom", bp,
>>> +                       loader_rommap[LOADER_PARAM].size,
>>> +                       loader_rommap[LOADER_PARAM].base);
>>> +
>>> +    g_free(bp);
>>> +
>>> +    loaderparams.a2 = cpu_mips_phys_to_kseg0(NULL, loader_rommap[LOADER_PARAM].base);
>>> +}
>>> +
>>> +static void init_boot_rom(void)
>>> +{
>>> +    const unsigned int boot_code[] = {
>>> +        0x40086000,   /* mfc0    t0, CP0_STATUS                               */
>>> +        0x240900E4,   /* li      t1, 0xe4         #set kx, sx, ux, erl        */
>>> +        0x01094025,   /* or      t0, t0, t1                                   */
>>> +        0x3C090040,   /* lui     t1, 0x40         #set bev                    */
>>> +        0x01094025,   /* or      t0, t0, t1                                   */
>>> +        0x40886000,   /* mtc0    t0, CP0_STATUS                               */
>>> +        0x00000000,
>>> +        0x40806800,   /* mtc0    zero, CP0_CAUSE                              */
>>> +        0x00000000,
>>> +        0x400A7801,   /* mfc0    t2, $15, 1                                   */
>>> +        0x314A00FF,   /* andi    t2, 0x0ff                                    */
>>> +        0x3C089000,   /* dli     t0, 0x900000003ff01000                       */
>>> +        0x00084438,
>>> +        0x35083FF0,
>>> +        0x00084438,
>>> +        0x35081000,
>>> +        0x314B0003,   /* andi    t3, t2, 0x3      #local cpuid                */
>>> +        0x000B5A00,   /* sll     t3, 8                                        */
>>> +        0x010B4025,   /* or      t0, t0, t3                                   */
>>> +        0x314C000C,   /* andi    t4, t2, 0xc      #node id                    */
>>> +        0x000C62BC,   /* dsll    t4, 42                                       */
>>> +        0x010C4025,   /* or      t0, t0, t4                                   */
>>> +                      /* WaitForInit:                                         */
>>> +        0xDD020020,   /* ld      v0, FN_OFF(t0)   #FN_OFF 0x020               */
>>> +        0x1040FFFE,   /* beqz    v0, WaitForInit                              */
>>> +        0x00000000,   /* nop                                                  */
>>> +        0xDD1D0028,   /* ld      sp, SP_OFF(t0)   #FN_OFF 0x028               */
>>> +        0xDD1C0030,   /* ld      gp, GP_OFF(t0)   #FN_OFF 0x030               */
>>> +        0xDD050038,   /* ld      a1, A1_OFF(t0)   #FN_OFF 0x038               */
>>> +        0x00400008,   /* jr      v0               #byebye                     */
>>> +        0x00000000,   /* nop                                                  */
>>> +        0x1000FFFF,   /* 1:  b   1b                                           */
>>> +        0x00000000,   /* nop                                                  */
>>> +
>>> +                      /* Reset                                                */
>>> +        0x3C0C9000,   /* dli     t0, 0x9000000010080010                       */
>>> +        0x358C0000,
>>> +        0x000C6438,
>>> +        0x358C1008,
>>> +        0x000C6438,
>>> +        0x358C0010,
>>> +        0x240D0000,   /* li      t1, 0x00                                     */
>>> +        0xA18D0000,   /* sb      t1, (t0)                                     */
>>> +        0x1000FFFF,   /* 1:  b   1b                                           */
>>> +        0x00000000,   /* nop                                                  */
>>> +
>>> +                      /* Shutdown                                             */
>>> +        0x3C0C9000,   /* dli     t0, 0x9000000010080010                       */
>>> +        0x358C0000,
>>> +        0x000C6438,
>>> +        0x358C1008,
>>> +        0x000C6438,
>>> +        0x358C0010,
>>> +        0x240D00FF,   /* li      t1, 0xff                                     */
>>> +        0xA18D0000,   /* sb      t1, (t0)                                     */
>>> +        0x1000FFFF,   /* 1:  b   1b                                           */
>>> +        0x00000000    /* nop                                                  */
>>> +    };
>>> +
>>> +    rom_add_blob_fixed("boot_rom", boot_code, sizeof(boot_code),
>>> +                        loader_rommap[LOADER_BOOTROM].base);
>>> +}
>>> +
>>> +static void fw_cfg_boot_set(void *opaque, const char *boot_device,
>>> +                            Error **errp)
>>> +{
>>> +    fw_cfg_modify_i16(opaque, FW_CFG_BOOT_DEVICE, boot_device[0]);
>>> +}
>>> +
>>> +static void fw_conf_init(unsigned long ram_size)
>>> +{
>>> +    FWCfgState *fw_cfg;
>>> +    hwaddr cfg_addr = virt_memmap[VIRT_FW_CFG].base;
>>> +
>>> +    fw_cfg = fw_cfg_init_mem_wide(cfg_addr, cfg_addr + 8, 8, 0, NULL);
>>> +    fw_cfg_add_i16(fw_cfg, FW_CFG_NB_CPUS, (uint16_t)current_machine->smp.cpus);
>>> +    fw_cfg_add_i16(fw_cfg, FW_CFG_MAX_CPUS, (uint16_t)current_machine->smp.max_cpus);
>>> +    fw_cfg_add_i64(fw_cfg, FW_CFG_RAM_SIZE, (uint64_t)ram_size);
>>> +    fw_cfg_add_i32(fw_cfg, FW_CFG_MACHINE_VERSION, 1);
>>> +    fw_cfg_add_i64(fw_cfg, FW_CFG_CPU_FREQ, get_cpu_freq());
>>> +    qemu_register_boot_set(fw_cfg_boot_set, fw_cfg);
>>> +}
>>> +
>>> +static int set_prom_cmdline(ram_addr_t initrd_offset, long initrd_size)
>>> +{
>>> +    hwaddr cmdline_vaddr;
>>> +    char memenv[32];
>>> +    char highmemenv[32];
>>> +    void *cmdline_buf;
>>> +    unsigned int *parg_env;
>>> +    int ret = 0;
>>> +
>>> +    /* Allocate cmdline_buf for command line. */
>>> +    cmdline_buf = g_malloc0(loader_memmap[LOADER_CMDLINE].size);
>>> +    cmdline_vaddr = cpu_mips_phys_to_kseg0(NULL,
>>> +                                           loader_memmap[LOADER_CMDLINE].base);
>>> +
>>> +    /*
>>> +     * Layout of cmdline_buf looks like this:
>>> +     * argv[0], argv[1], 0, env[0], env[1], ... env[i], 0,
>>> +     * argv[0]'s data, argv[1]'s data, env[0]'data, ..., env[i]'s data, 0
>>> +     */
>>> +    parg_env = (void *)cmdline_buf;
>>> +
>>> +    ret = (3 + 1) * 4;
>>> +    *parg_env++ = cmdline_vaddr + ret;
>>> +    ret += (1 + snprintf(cmdline_buf + ret, 256 - ret, "g"));
>>> +
>>> +    /* argv1 */
>>> +    *parg_env++ = cmdline_vaddr + ret;
>>> +    if (initrd_size > 0)
>>> +        ret += (1 + snprintf(cmdline_buf + ret, 256 - ret,
>>> +                "rd_start=0x" TARGET_FMT_lx " rd_size=%li %s",
>>> +                cpu_mips_phys_to_kseg0(NULL, initrd_offset),
>>> +                initrd_size, loaderparams.kernel_cmdline));
>>> +    else
>>> +        ret += (1 + snprintf(cmdline_buf + ret, 256 - ret, "%s",
>>> +                loaderparams.kernel_cmdline));
>>> +
>>> +    /* argv2 */
>>> +    *parg_env++ = cmdline_vaddr + 4 * ret;
>>> +
>>> +    /* env */
>>> +    sprintf(memenv, "%d", 256);
>>> +    sprintf(highmemenv, "%ld", (unsigned long)(loaderparams.ram_size / MiB) - 256);
>>> +
>>> +    rom_add_blob_fixed("cmdline", cmdline_buf,
>>> +                       loader_memmap[LOADER_CMDLINE].size,
>>> +                       loader_memmap[LOADER_CMDLINE].base);
>>> +
>>> +    g_free(cmdline_buf);
>>> +
>>> +    loaderparams.a0 = 2;
>>> +    loaderparams.a1 = cmdline_vaddr;
>>> +
>>> +    return 0;
>>> +}
>>> +
>>> +static uint64_t load_kernel(CPUMIPSState *env)
>>> +{
>>> +    long kernel_size;
>>> +    ram_addr_t initrd_offset;
>>> +    uint64_t kernel_entry, kernel_low, kernel_high, initrd_size;
>>> +
>>> +    kernel_size = load_elf(loaderparams.kernel_filename, NULL,
>>> +                           cpu_mips_kseg0_to_phys, NULL,
>>> +                           (uint64_t *)&kernel_entry,
>>> +                           (uint64_t *)&kernel_low, (uint64_t *)&kernel_high,
>>> +                           NULL, 0, EM_MIPS, 1, 0);
>>> +    if (kernel_size < 0) {
>>> +        error_report("could not load kernel '%s': %s",
>>> +                     loaderparams.kernel_filename,
>>> +                     load_elf_strerror(kernel_size));
>>> +        exit(1);
>>> +    }
>>> +
>>> +    /* load initrd */
>>> +    initrd_size = 0;
>>> +    initrd_offset = 0;
>>> +    if (loaderparams.initrd_filename) {
>>> +        initrd_size = get_image_size(loaderparams.initrd_filename);
>>> +        if (initrd_size > 0) {
>>> +            initrd_offset = (kernel_high + ~INITRD_PAGE_MASK) &
>>> +                            INITRD_PAGE_MASK;
>>> +            initrd_offset = MAX(initrd_offset,
>>> +                                loader_memmap[LOADER_INITRD].base);
>>> +
>>> +            if (initrd_offset + initrd_size > ram_size) {
>>> +                error_report("memory too small for initial ram disk '%s'",
>>> +                             loaderparams.initrd_filename);
>>> +                exit(1);
>>> +            }
>>> +
>>> +            initrd_size = load_image_targphys(loaderparams.initrd_filename,
>>> +                                              initrd_offset,
>>> +                                              ram_size - initrd_offset);
>>> +        }
>>> +
>>> +        if (initrd_size == (target_ulong) -1) {
>>> +            error_report("could not load initial ram disk '%s'",
>>> +                         loaderparams.initrd_filename);
>>> +            exit(1);
>>> +        }
>>> +    }
>>> +
>>> +    /* Setup prom cmdline. */
>>> +    set_prom_cmdline(initrd_offset, initrd_size);
>>> +
>>> +    return kernel_entry;
>>> +}
>>> +
>>> +static void main_cpu_reset(void *opaque)
>>> +{
>>> +    MIPSCPU *cpu = opaque;
>>> +    CPUMIPSState *env = &cpu->env;
>>> +
>>> +    cpu_reset(CPU(cpu));
>>> +
>>> +    /* Loongson-3 reset stuff */
>>> +    if (loaderparams.kernel_filename) {
>>> +        if (cpu == MIPS_CPU(first_cpu)) {
>>> +            env->active_tc.gpr[4] = loaderparams.a0;
>>> +            env->active_tc.gpr[5] = loaderparams.a1;
>>> +            env->active_tc.gpr[6] = loaderparams.a2;
>>> +            env->active_tc.PC = loaderparams.kernel_entry;
>>> +        }
>>> +        env->CP0_Status &= ~((1 << CP0St_BEV) | (1 << CP0St_ERL));
>>> +    }
>>> +}
>>> +
>>> +static inline void loongson3_virt_devices_init(MachineState *machine, DeviceState *pic)
>>> +{
>>> +    int i;
>>> +    qemu_irq irq;
>>> +    PCIBus *pci_bus;
>>> +    DeviceState *dev;
>>> +    MemoryRegion *pio_alias;
>>> +    MemoryRegion *mmio_alias, *mmio_reg;
>>> +    MemoryRegion *ecam_alias, *ecam_reg;
>>> +
>>> +    dev = qdev_new(TYPE_GPEX_HOST);
>>> +    sysbus_realize_and_unref(SYS_BUS_DEVICE(dev), &error_fatal);
>>> +    pci_bus = PCI_HOST_BRIDGE(dev)->bus;
>>> +
>>> +    ecam_alias = g_new0(MemoryRegion, 1);
>>> +    ecam_reg = sysbus_mmio_get_region(SYS_BUS_DEVICE(dev), 0);
>>> +    memory_region_init_alias(ecam_alias, OBJECT(dev), "pcie-ecam",
>>> +                             ecam_reg, 0, virt_memmap[VIRT_PCIE_ECAM].size);
>>> +    memory_region_add_subregion(get_system_memory(),
>>> +                                virt_memmap[VIRT_PCIE_ECAM].base, ecam_alias);
>>> +
>>> +    mmio_alias = g_new0(MemoryRegion, 1);
>>> +    mmio_reg = sysbus_mmio_get_region(SYS_BUS_DEVICE(dev), 1);
>>> +    memory_region_init_alias(mmio_alias, OBJECT(dev), "pcie-mmio",
>>> +                             mmio_reg, virt_memmap[VIRT_PCIE_MMIO].base,
>>> +                             virt_memmap[VIRT_PCIE_MMIO].size);
>>> +    memory_region_add_subregion(get_system_memory(),
>>> +                                virt_memmap[VIRT_PCIE_MMIO].base, mmio_alias);
>>> +
>>> +    pio_alias = g_new0(MemoryRegion, 1);
>>> +    memory_region_init_alias(pio_alias, OBJECT(dev), "pcie-pio",
>>> +                             get_system_io(), 0, virt_memmap[VIRT_PCIE_PIO].size);
>>> +    memory_region_add_subregion(get_system_memory(),
>>> +                                virt_memmap[VIRT_PCIE_PIO].base, pio_alias);
>>> +    sysbus_mmio_map(SYS_BUS_DEVICE(dev), 2, virt_memmap[VIRT_PCIE_PIO].base);
>>> +
>>> +    for (i = 0; i < GPEX_NUM_IRQS; i++) {
>>> +        irq = qdev_get_gpio_in(pic, PCIE_IRQ_BASE + i);
>>> +        sysbus_connect_irq(SYS_BUS_DEVICE(dev), i, irq);
>>> +        gpex_set_irq_num(GPEX_HOST(dev), i, PCIE_IRQ_BASE + i);
>>> +    }
>>> +
>>> +    pci_vga_init(pci_bus);
>>> +
>>> +    if (defaults_enabled()) {
>>> +        pci_create_simple(pci_bus, -1, "pci-ohci");
>>> +        usb_create_simple(usb_bus_find(-1), "usb-kbd");
>>> +        usb_create_simple(usb_bus_find(-1), "usb-tablet");
>>> +    }
>>> +
>>> +    for (i = 0; i < nb_nics; i++) {
>>> +        NICInfo *nd = &nd_table[i];
>>> +
>>> +        if (!nd->model) {
>>> +            nd->model = g_strdup("virtio");
>>> +        }
>>> +
>>> +        pci_nic_init_nofail(nd, pci_bus, nd->model, NULL);
>>> +    }
>>> +}
>>> +
>>> +static void mips_loongson3_virt_init(MachineState *machine)
>>> +{
>>> +    int i;
>>> +    long bios_size;
>>> +    MIPSCPU *cpu;
>>> +    CPUMIPSState *env;
>>> +    DeviceState *liointc;
>>> +    char *filename;
>>> +    const char *kernel_cmdline = machine->kernel_cmdline;
>>> +    const char *kernel_filename = machine->kernel_filename;
>>> +    const char *initrd_filename = machine->initrd_filename;
>>> +    ram_addr_t ram_size = machine->ram_size;
>>> +    MemoryRegion *address_space_mem = get_system_memory();
>>> +    MemoryRegion *ram = g_new(MemoryRegion, 1);
>>> +    MemoryRegion *bios = g_new(MemoryRegion, 1);
>>> +    MemoryRegion *iomem = g_new(MemoryRegion, 1);
>>> +
>>> +    /* TODO: TCG will support all CPU types */
>>> +    if (!kvm_enabled()) {
>>> +        if (!machine->cpu_type) {
>>> +            machine->cpu_type = MIPS_CPU_TYPE_NAME("Loongson-3A1000");
>>> +        }
>>> +        if (!strstr(machine->cpu_type, "Loongson-3A1000")) {
>>> +            error_report("Loongson-3/TCG needs cpu type Loongson-3A1000");
>>> +            exit(1);
>>> +        }
>>
>> IIUC here you need to check machine->smp.cpus is 4 or 8 for the 3A1000.
>> It would be easier if you model this as a qdev SoC, and this model
>> cares to create the 4/8 cores (QEMU MIPSCPU).
>>
>> You defined max_cpu = LOONGSON_MAX_VCPUS = 16, this seems an impossible
>> configuration for the 3A1000.
 >
> There are 4 cores in a SoC, but Loongson-3 support multi-sockets, more
> than 4 vcpus will be treated as multi-sockets automatically in guests.
> And current linux kernel also handle the case that only boot part of 4
> cores in a socket.

What I want to avoid is user booting the machine with 3 or 5 vCPUs,
then complain booting Linux isn't working. It is simpler to check
the number of vCPUs matches the hardware possibilities.

> 
>>
>>> +    } else {
>>> +        if (!machine->cpu_type) {
>>> +            machine->cpu_type = MIPS_CPU_TYPE_NAME("Loongson-3A4000");
>>> +        }
>>> +        if (!strstr(machine->cpu_type, "Loongson-3A4000")) {
>>> +            error_report("Loongson-3/KVM needs cpu type Loongson-3A4000");
>>> +            exit(1);
>>> +        }
>>
>> Similar comment, as the 3A4000 is also a quad-core.
>>
>>> +    }
>>> +
>>> +    if (ram_size < 512 * MiB) {
>>> +        error_report("Loongson-3 machine needs at least 512MB memory");
>>> +        exit(1);
>>> +    }
>>> +
>>> +    /*
>>> +     * The whole MMIO range among configure registers doesn't generate
>>> +     * exception when accessing invalid memory. Create an unimplememted
>>> +     * device to emulate this feature.
>>> +     */
>>> +    create_unimplemented_device("fallback", 0x10000000, 0x30000000);
>>
>> The secondary crosswise switch description is hard to follow:
>>
>> * 2.4 Address routing distribution and configuration
>>
>> According  to  the  default  register  configuration,  CPU [...]
>> 0x10000000-0x1fffffff  of  CPU  (256M)  is  mapped  to
>> 0x10000000-0x1fffffff  of  PCI,  and  0x80000000  of  PCIDMA.
>> In addition, when read access to illegal addresses occurs due to CPU
>> guess execution, all 8 address Windows fail to hit, ?
>>
>> Table 2-9 XBAR level 2 default address configuration
>>                     base                    high                     owner
>> 0 x0000_0000_1000_0000  0 x0000_0000_2000_0000  Low speed I/O (PCI, etc)
>>
>> * 14.4 Secondary cross-switch address window
>>
>> After the address window is configured, the system address
>> 0x0000_2000_0000 is added-- 0x0000_2FFFF_FFFF  maps  to
>> 0x0000_0000_0000  -- 0x0000_0FFF_FFFF  of  memory  controller 0.An
>> access to 0x0000_2000_0000 at this time will result in the original
>> enabledThe value stored at address 0x0000_0000_0000.
>>
>> But see:
>>
>> * 14.6.3 Low speed device address window
>>
>> Here are defined the peripherals in the 0x1c00_0000-0x1ff0_ffff range.
>>
>> * 15.1 System memory space
>>
>> IO device, 0x1000_0000 --  0x1FFF_FFFF
>>
>> * 16 Memory allocation for system X
>>
>> ... divide  the  256M  PCI  space  (0x10000000~0x20000000)  into  two
>> parts:  0x10000000~0x17ffffff for mem space and 0x18000000~0x20000000
>> for IO space.
>>
>> I still don't understand what is in the 0x20000000-0x30000000 range.
> Loongson's user manual is a little confusing, as a native Chinese I
> also feel uncomfortable sometimes. :)
> Generally speaking, Loongson-3's address space is configurable via
> address windows, and the recommended configurations is like this:
> 0x00000000-0x10000000   Low RAM
> 0x10000000-0x40000000   ROM and MMIO Registers (such as BIOS_ROM at
> 0x1fc00000, UART at 0x1fe001e0, LIOINTC at 0x3ff00140)
> 0x40000000-0x80000000  PCI MEM
> 0x80000000-TOM             High RAM

Having a "fallback" region catching everything is not very helpful
when debugging. Listing each unimplemented peripheral is more useful:

   create_unimplemented_device("LPC MEM", 0x1c000000, 32 * MiB);
   ...
   create_unimplemented_device("UART1",   0x1fe001e8, 8);
   create_unimplemented_device("SPI",     0x1fe001f0, 16);
   create_unimplemented_device("LPC IO",  0x1ff00000, 64 * KiB);
   ...

> 
> PCI DMA of 0x10000000-0x1fffffff is a legacy region from
> Loongson-2E/2F, and be cancelled in Loongson-3's configuration.
> In real hardware, there should be a default "big enough" address
> window to catch illegal address, return 0 for read access.
> Yes, there is "nothing" in 0x20000000-0x30000000, because it is
> undocumented which means "reserved for internal usage".

If it is reserved, then the guest shouldn't be trying to use it...

>>
>>> +
>>> +    liointc = qdev_new("loongson.liointc");
>>> +    sysbus_realize_and_unref(SYS_BUS_DEVICE(liointc), &error_fatal);
>>> +
>>> +    sysbus_mmio_map(SYS_BUS_DEVICE(liointc), 0, virt_memmap[VIRT_LIOINTC].base);
>>> +
>>> +    for (i = 0; i < machine->smp.cpus; i++) {
>>> +        int ip;
>>> +
>>> +        /* init CPUs */
>>> +        cpu = MIPS_CPU(cpu_create(machine->cpu_type));
>>> +
>>> +        /* Init internal devices */
>>> +        cpu_mips_irq_init_cpu(cpu);
>>> +        cpu_mips_clock_init(cpu);
>>> +        qemu_register_reset(main_cpu_reset, cpu);
>>> +
>>> +        if (i >= 4) {
>>> +            continue; /* Only node-0 can be connected to LIOINTC */
>>> +        }
>>> +
>>> +        for (ip = 0; ip < 4 ; ip++) {
>>> +            int pin = i * 4 + ip;
>>> +            sysbus_connect_irq(SYS_BUS_DEVICE(liointc),
>>> +                               pin, cpu->env.irq[ip + 2]);
>>> +        }
>>> +    }
>>> +    env = &MIPS_CPU(first_cpu)->env;
>>> +
>>> +    /* Allocate RAM/BIOS, 0x00000000~0x10000000 is alias of 0x80000000~0x90000000 */
>>> +    memory_region_init_rom(bios, NULL, "loongson3.bios",
>>> +                           virt_memmap[VIRT_BIOS_ROM].size, &error_fatal);
>>> +    memory_region_init_alias(ram, NULL, "loongson3.lowmem",
>>> +                           machine->ram, 0, virt_memmap[VIRT_LOWMEM].size);
>>> +    memory_region_init_io(iomem, NULL, &loongson3_pm_ops,
>>> +                           NULL, "loongson3_pm", virt_memmap[VIRT_PM].size);
>>> +
>>> +    memory_region_add_subregion(address_space_mem,
>>> +                      virt_memmap[VIRT_LOWMEM].base, ram);
>>> +    memory_region_add_subregion(address_space_mem,
>>> +                      virt_memmap[VIRT_BIOS_ROM].base, bios);
>>> +    memory_region_add_subregion(address_space_mem,
>>> +                      virt_memmap[VIRT_HIGHMEM].base, machine->ram);
>>> +    memory_region_add_subregion(address_space_mem,
>>> +                      virt_memmap[VIRT_PM].base, iomem);
>>> +
>>> +    /*
>>> +     * We do not support flash operation, just loading bios.bin as raw BIOS.
>>> +     * Please use -L to set the BIOS path and -bios to set bios name.
>>> +     */
>>> +
>>> +    if (kernel_filename) {
>>> +        loaderparams.cpu_freq = get_cpu_freq();
>>> +        loaderparams.ram_size = ram_size;
>>> +        loaderparams.kernel_filename = kernel_filename;
>>> +        loaderparams.kernel_cmdline = kernel_cmdline;
>>> +        loaderparams.initrd_filename = initrd_filename;
>>> +        loaderparams.kernel_entry = load_kernel(env);
>>> +
>>> +        init_boot_rom();
>>> +        init_boot_param();
>>> +    } else {
>>> +        if (bios_name == NULL) {
>>> +                bios_name = LOONGSON3_BIOSNAME;
>>> +        }
>>> +        filename = qemu_find_file(QEMU_FILE_TYPE_BIOS, bios_name);
>>> +        if (filename) {
>>> +            bios_size = load_image_targphys(filename,
>>> +                                            virt_memmap[VIRT_BIOS_ROM].base,
>>> +                                            virt_memmap[VIRT_BIOS_ROM].size);
>>> +            g_free(filename);
>>> +        } else {
>>> +            bios_size = -1;
>>> +        }
>>> +
>>> +        if ((bios_size < 0 || bios_size > virt_memmap[VIRT_BIOS_ROM].size) &&
>>> +            !kernel_filename && !qtest_enabled()) {
>>> +            error_report("Could not load MIPS bios '%s'", bios_name);
>>> +            exit(1);
>>> +        }
>>> +
>>> +        fw_conf_init(ram_size);
>>> +    }
>>> +
>>> +    msi_nonbroken = true;
>>> +    loongson3_virt_devices_init(machine, liointc);
>>> +
>>> +    sysbus_create_simple("goldfish_rtc", virt_memmap[VIRT_RTC].base,
>>> +                         qdev_get_gpio_in(liointc, RTC_IRQ));
>>> +
>>> +    serial_mm_init(address_space_mem, virt_memmap[VIRT_UART].base, 0,
>>> +                   qdev_get_gpio_in(liointc, UART_IRQ), 115200, serial_hd(0),
>>> +                   DEVICE_NATIVE_ENDIAN);
>>
>> You need to split the SoC part from the machine part.
> What do you mean? UART is SoC part and put it near LIOINTC?

I understand the 3A4000 is a system-on-chip (SoC) with various
peripherals (INTC, HT Bus, UART/SPI/I2C Ctrl, GPIO, Temp Sensors,
DDR/ECC Ctrl, ...). Then the Godson-3 is the CPU unit,
embedding the various GS464V cores.

Maybe as:

  +-------------------Machine-----------------+
  |                                           |
  | +--------------Loongson-3------------+    |
  | |                                    |    |
  | |  +------+Godson+3+----+  +----+    |    |
  | |  |                    |  |TEMP|    |    |
  | |  | +------+  +------+ |  +----+    |    |
  | |  | |GS464V|  |GS464V| |            |    |
  | |  | |=1vCPU|  |=1vCPU| |    +-------+    |
  | |  | +------+  +------+ |    |       |    |
  | |  |                    |    | GPIO  |    |
  | |  | +------+  +------+ |    |       |    |
  | |  | |GS464V|  |GS464V| |    +-------+    |
  | |  | |=1vCPU|  |=1vCPU| |            |    |
  | |  | +------+  +------+ |    +-------+    |
  | |  |                    |    |       |    |
  | |  +--------------------+    | LINTC |    |
  | |                            |       |    |
  | |                            +-------+    |
  | |                                    |    |
  | | +------+  +-----+  +-----+ +-----+ |    |
  | | | UART |  | SPI |  | I2C | | ... | |    |
  | +------------------------------------+    |
  |                                           |
  | +-------------+               +-------+   |
  | |    DRAM     |               | FLASH |   |
  | +-------------+               +-------+   |
  +-------------------------------------------+

QEMU tries to model each block as QOM.

Anyway if you are happy with the current state,
this can be improved later.

> 
>>
>>> +}
>>> +
>>> +static void mips_loongson3_virt_machine_init(MachineClass *mc)
>>> +{
>>> +    mc->desc = "Loongson-3 Virtualization Platform";
>>> +    mc->init = mips_loongson3_virt_init;
>>> +    mc->block_default_type = IF_IDE;
>>
>> Don't you need min_cpus = 4?
> I think this is needn't.

Well, you can not have a GS464V with 1 vCPU.

> 
>>
>>> +    mc->max_cpus = LOONGSON_MAX_VCPUS;
>>> +    mc->default_ram_id = "loongson3.highram";
>>> +    mc->default_ram_size = 1600 * MiB;
>>> +    mc->kvm_type = mips_kvm_type;
>>> +    mc->minimum_page_bits = 14;
>>> +}
>>> +
>>> +DEFINE_MACHINE("loongson3-virt", mips_loongson3_virt_machine_init)
>>> diff --git a/hw/mips/meson.build b/hw/mips/meson.build
>>> index c98391c..72db43c 100644
>>> --- a/hw/mips/meson.build
>>> +++ b/hw/mips/meson.build
>>> @@ -1,6 +1,7 @@
>>>    mips_ss = ss.source_set()
>>>    mips_ss.add(files('addr.c', 'mips_int.c', 'fw_cfg.c'))
>>>    mips_ss.add(when: 'CONFIG_FULOONG', if_true: files('fuloong2e.c'))
>>> +mips_ss.add(when: 'CONFIG_LOONGSON3V', if_true: files('loongson3_bootp.c', 'loongson3_virt.c'))
>>>    mips_ss.add(when: 'CONFIG_JAZZ', if_true: files('jazz.c'))
>>>    mips_ss.add(when: 'CONFIG_MALTA', if_true: files('gt64xxx_pci.c', 'malta.c'))
>>>    mips_ss.add(when: 'CONFIG_MIPSSIM', if_true: files('mipssim.c'))
>>>
> Huacai
>
Huacai Chen Oct. 13, 2020, 11:12 a.m. UTC | #4
Hi, Philippe,

On Mon, Oct 12, 2020 at 4:12 PM Philippe Mathieu-Daudé <f4bug@amsat.org> wrote:
>
> On 10/11/20 4:53 AM, Huacai Chen wrote:
> > Hi, Philippe,
> >
> > On Sat, Oct 10, 2020 at 5:09 PM Philippe Mathieu-Daudé <f4bug@amsat.org> wrote:
> >>
> >> Hi Huacai,
> >>
> >> On 10/7/20 10:39 AM, Huacai Chen wrote:
> >>> Add Loongson-3 based machine support, it use liointc as the interrupt
> >>> controler and use GPEX as the pci controller. Currently it can work with
> >>> both TCG and KVM.
> >>>
> >>> As the machine model is not based on any exiting physical hardware, the
> >>> name of the machine is "loongson3-virt". It may be superseded in future
> >>> by a real machine model. If this happens, then a regular deprecation
> >>> procedure shall occur for "loongson3-virt" machine.
> >>>
> >>> We now already have a full functional Linux kernel (based on Linux-5.4.x
> >>> LTS, the kvm host side and guest side have both been upstream for Linux-
> >>> 5.9, but Linux-5.9 has not been released yet) here:
> >>>
> >>> https://github.com/chenhuacai/linux
> >>>
> >>> Of course the upstream kernel is also usable (though it is "unstable"
> >>> now):
> >>>
> >>> https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
> >>>
> >>> How to use QEMU/Loongson-3?
> >>> 1, Download kernel source from the above URL;
> >>> 2, Build a kernel with arch/mips/configs/loongson3_defconfig;
> >>> 3, Boot a Loongson-3A4000 host with this kernel (for KVM mode);
> >>> 4, Build QEMU-master with this patchset;
> >>> 5, modprobe kvm (only necessary for KVM mode);
> >>> 6, Use QEMU with TCG:
> >>>          qemu-system-mips64el -M loongson3-virt,accel=tcg -cpu Loongson-3A1000 -kernel <path_to_kernel> -append ...
> >>>      Use QEMU with KVM:
> >>>          qemu-system-mips64el -M loongson3-virt,accel=kvm -cpu Loongson-3A4000 -kernel <path_to_kernel> -append ...
> >>>
> >>>      The "-cpu" parameter is optional here and QEMU will use the correct type for TCG/KVM automatically.
> >>>
> >>> Signed-off-by: Huacai Chen <chenhc@lemote.com>
> >>> Co-developed-by: Jiaxun Yang <jiaxun.yang@flygoat.com>
> >>> ---
> >>>    default-configs/devices/mips64el-softmmu.mak |   1 +
> >>>    hw/mips/Kconfig                              |  12 +
> >>>    hw/mips/loongson3_bootp.c                    | 162 +++++++
> >>>    hw/mips/loongson3_bootp.h                    | 225 ++++++++++
> >>
> >> In a previous version I asked if you could split the bootp* files
> >> (firmware related) in a previous separate patch to ease the review
> >> of the machine part.
>  >
> > In previous version you told me to split the fw_cfg to a separate
> > patch, but split the efi-related helpers to seprate files (not to a
> > patch). But anyway, I will split them to a patch in the next version.
>
> Sorry if I wasn't clear enough. It is very hard to review a patch
> of more than 1000 lines of C code without loosing focus or missing
> problems. It explains why big patches might stay unreviewed on the
> list. If you can split in smaller logical units, it will be very
> helpful.
>
> Peter Maydell rule of thumb is to keep patch below 200 lines.
> This is a good limit.
>
> >
> >>
> >>>    hw/mips/loongson3_virt.c                     | 615 +++++++++++++++++++++++++++
> >>>    hw/mips/meson.build                          |   1 +
> >>>    6 files changed, 1016 insertions(+)
> >> [...]
> >>
> >>> diff --git a/hw/mips/loongson3_virt.c b/hw/mips/loongson3_virt.c
> >>> new file mode 100644
> >>> index 0000000..4e573d6
> >>> --- /dev/null
> >>> +++ b/hw/mips/loongson3_virt.c
> >>> @@ -0,0 +1,615 @@
> >>> +/*
> >>> + * Generic Loongson-3 Platform support
> >>> + *
> >>> + * Copyright (c) 2017-2020 Huacai Chen (chenhc@lemote.com)
> >>> + * Copyright (c) 2017-2020 Jiaxun Yang <jiaxun.yang@flygoat.com>
> >>> + *
> >>> + * This program is free software: you can redistribute it and/or modify
> >>> + * it under the terms of the GNU General Public License as published by
> >>> + * the Free Software Foundation, either version 2 of the License, or
> >>> + * (at your option) any later version.
> >>> + *
> >>> + * This program is distributed in the hope that it will be useful,
> >>> + * but WITHOUT ANY WARRANTY; without even the implied warranty of
> >>> + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
> >>> + * GNU General Public License for more details.
> >>> + *
> >>> + * You should have received a copy of the GNU General Public License
> >>> + * along with this program. If not, see <https://www.gnu.org/licenses/>.
> >>> + */
> >>> +
> >>> +/*
> >>> + * Generic virtualized PC Platform based on Loongson-3 CPU (MIPS64R2 with
> >>> + * extensions, 800~2000MHz)
> >>> + */
> >>> +
> >>> +#include "qemu/osdep.h"
> >>> +#include "qemu-common.h"
> >>> +#include "qemu/units.h"
> >>> +#include "qemu/cutils.h"
> >>> +#include "qapi/error.h"
> >>> +#include "cpu.h"
> >>> +#include "elf.h"
> >>> +#include "kvm_mips.h"
> >>> +#include "hw/boards.h"
> >>> +#include "hw/char/serial.h"
> >>> +#include "hw/mips/mips.h"
> >>> +#include "hw/mips/cpudevs.h"
> >>> +#include "hw/mips/fw_cfg.h"
> >>> +#include "hw/mips/loongson3_bootp.h"
> >>> +#include "hw/misc/unimp.h"
> >>> +#include "hw/intc/i8259.h"
> >>> +#include "hw/loader.h"
> >>> +#include "hw/isa/superio.h"
> >>> +#include "hw/pci/msi.h"
> >>> +#include "hw/pci/pci.h"
> >>> +#include "hw/pci/pci_host.h"
> >>> +#include "hw/pci-host/gpex.h"
> >>> +#include "hw/rtc/mc146818rtc.h"
> >>> +#include "hw/usb.h"
> >>> +#include "net/net.h"
> >>> +#include "exec/address-spaces.h"
> >>> +#include "sysemu/kvm.h"
> >>> +#include "sysemu/qtest.h"
> >>> +#include "sysemu/reset.h"
> >>> +#include "sysemu/runstate.h"
> >>> +#include "qemu/log.h"
> >>> +#include "qemu/error-report.h"
> >>> +
> >>> +#define PM_CNTL_MODE          0x10
> >>> +
> >>> +#define LOONGSON_MAX_VCPUS      16
> >>> +
> >>> +#define LOONGSON3_BIOSNAME "bios_loongson3.bin"
> >>
> >> Where is that file?
>  >
> > I don't know the policy of QEMU's binary file, just put that in the
> > roms directory?
>
> If this is a closed source binary, we reference the URL where it can
> be downloaded accepting eventual EULA.
> If it is open source, the project is added as submodule. QEMU then
> provides a link to how to build the firmware, or if there is no such
> documentation, buildsys machinery is added to QEMU to build to it
> (see roms/Makefile).
OK, now the firmware is close-source (maybe open source in future), so
I will put an URL here.

>
> >
> >>
> >>> +
> >>> +#define UART_IRQ            0
> >>> +#define RTC_IRQ             1
> >>> +#define PCIE_IRQ_BASE       2
> >>> +
> >>> +const struct MemmapEntry virt_memmap[] = {
> >>> +    [VIRT_LOWMEM] =      { 0x00000000,    0x10000000 },
> >>> +    [VIRT_PM] =          { 0x10080000,         0x100 },
> >>> +    [VIRT_FW_CFG] =      { 0x10080100,         0x100 },
> >>> +    [VIRT_RTC] =         { 0x10081000,        0x1000 },
> >>> +    [VIRT_PCIE_PIO] =    { 0x18000000,       0x80000 },
> >>> +    [VIRT_PCIE_ECAM] =   { 0x1a000000,     0x2000000 },
> >>> +    [VIRT_BIOS_ROM] =    { 0x1fc00000,      0x200000 },
> >>> +    [VIRT_UART] =        { 0x1fe001e0,           0x8 },
> >>
> >> See below about this mapping.
> >>
> >>> +    [VIRT_LIOINTC] =     { 0x3ff01400,          0x64 },
> >>> +    [VIRT_PCIE_MMIO] =   { 0x40000000,    0x40000000 },
> >>> +    [VIRT_HIGHMEM] =     { 0x80000000,           0x0 }, /* Variable */
> >>> +};
> >>> +
> >>> +static const struct MemmapEntry loader_memmap[] = {
> >>> +    [LOADER_KERNEL] =    { 0x00000000,     0x4000000 },
> >>> +    [LOADER_INITRD] =    { 0x04000000,           0x0 }, /* Variable */
> >>> +    [LOADER_CMDLINE] =   { 0x0ff00000,      0x100000 },
> >>> +};
> >>> +
> >>> +static const struct MemmapEntry loader_rommap[] = {
> >>> +    [LOADER_BOOTROM] =   { 0x1fc00000,        0x1000 },
> >>> +    [LOADER_PARAM] =     { 0x1fc01000,       0x10000 },
> >>> +};
> >>> +
> >>> +static struct _loaderparams {
> >>> +    uint64_t cpu_freq;
> >>> +    uint64_t ram_size;
> >>> +    const char *kernel_cmdline;
> >>> +    const char *kernel_filename;
> >>> +    const char *initrd_filename;
> >>> +    uint64_t kernel_entry;
> >>> +    uint64_t a0, a1, a2;
> >>> +} loaderparams;
> >>> +
> >>> +static uint64_t loongson3_pm_read(void *opaque, hwaddr addr, unsigned size)
> >>> +{
> >>> +    return 0;
> >>> +}
> >>> +
> >>> +static void loongson3_pm_write(void *opaque, hwaddr addr, uint64_t val, unsigned size)
> >>> +{
> >>> +    if (addr != PM_CNTL_MODE) {
> >>> +        return;
> >>> +    }
> >>> +
> >>> +    switch (val) {
> >>> +    case 0x00:
> >>> +        qemu_system_reset_request(SHUTDOWN_CAUSE_GUEST_RESET);
> >>> +        return;
> >>> +    case 0xff:
> >>> +        qemu_system_shutdown_request(SHUTDOWN_CAUSE_GUEST_SHUTDOWN);
> >>> +        return;
> >>> +    default:
> >>> +        return;
> >>> +    }
> >>> +}
> >>> +
> >>> +static const MemoryRegionOps loongson3_pm_ops = {
> >>> +    .read  = loongson3_pm_read,
> >>> +    .write = loongson3_pm_write,
> >>> +    .endianness = DEVICE_NATIVE_ENDIAN,
> >>> +};
> >>> +
> >>> +#define DEF_TCG_FREQ (200 * 1000 * 1000)
> >>> +#define DEF_KVM_FREQ (1600 * 1000 * 1000)
> >>> +
> >>> +static uint64_t get_cpu_freq(void)
> >>> +{
> >>> +#ifdef CONFIG_KVM
> >>> +    int ret;
> >>> +    uint64_t freq;
> >>> +    struct kvm_one_reg freq_reg = {
> >>> +        .id = KVM_REG_MIPS_COUNT_HZ,
> >>> +        .addr = (uintptr_t)(&freq)
> >>> +    };
> >>> +
> >>> +    if (kvm_enabled()) {
> >>> +        ret = kvm_vcpu_ioctl(first_cpu, KVM_GET_ONE_REG, &freq_reg);
> >>> +        if (ret < 0) {
> >>> +            return DEF_KVM_FREQ;
> >>> +        }
> >>> +        return freq * 2;
> >>> +    } else {
> >>> +        /*
> >>> +         * TCG has a default CP0 Timer period 10 ns, which is 100MHz,
> >>> +         * CPU frequency is defined as double of CP0 timer frequency.
> >>> +         */
> >>> +        return DEF_TCG_FREQ;
> >>> +    }
> >>> +#else
> >>> +    return DEF_TCG_FREQ;
> >>> +#endif
> >>> +}
> >>> +
> >>> +static void init_boot_param(void)
> >>> +{
> >>> +    void *p;
> >>> +    struct boot_params *bp;
> >>> +
> >>> +    p = g_malloc0(loader_rommap[LOADER_PARAM].size);
> >>> +    bp = p;
> >>> +
> >>> +    stw_le_p(&bp->efi.smbios.vers, 1);
> >>> +    init_reset_system(&(bp->reset_system));
> >>> +    p += ROUND_UP(sizeof(struct boot_params), 64);
> >>> +    init_loongson_params(&(bp->efi.smbios.lp), p,
> >>> +                         loaderparams.cpu_freq, loaderparams.ram_size);
> >>> +
> >>> +    rom_add_blob_fixed("params_rom", bp,
> >>> +                       loader_rommap[LOADER_PARAM].size,
> >>> +                       loader_rommap[LOADER_PARAM].base);
> >>> +
> >>> +    g_free(bp);
> >>> +
> >>> +    loaderparams.a2 = cpu_mips_phys_to_kseg0(NULL, loader_rommap[LOADER_PARAM].base);
> >>> +}
> >>> +
> >>> +static void init_boot_rom(void)
> >>> +{
> >>> +    const unsigned int boot_code[] = {
> >>> +        0x40086000,   /* mfc0    t0, CP0_STATUS                               */
> >>> +        0x240900E4,   /* li      t1, 0xe4         #set kx, sx, ux, erl        */
> >>> +        0x01094025,   /* or      t0, t0, t1                                   */
> >>> +        0x3C090040,   /* lui     t1, 0x40         #set bev                    */
> >>> +        0x01094025,   /* or      t0, t0, t1                                   */
> >>> +        0x40886000,   /* mtc0    t0, CP0_STATUS                               */
> >>> +        0x00000000,
> >>> +        0x40806800,   /* mtc0    zero, CP0_CAUSE                              */
> >>> +        0x00000000,
> >>> +        0x400A7801,   /* mfc0    t2, $15, 1                                   */
> >>> +        0x314A00FF,   /* andi    t2, 0x0ff                                    */
> >>> +        0x3C089000,   /* dli     t0, 0x900000003ff01000                       */
> >>> +        0x00084438,
> >>> +        0x35083FF0,
> >>> +        0x00084438,
> >>> +        0x35081000,
> >>> +        0x314B0003,   /* andi    t3, t2, 0x3      #local cpuid                */
> >>> +        0x000B5A00,   /* sll     t3, 8                                        */
> >>> +        0x010B4025,   /* or      t0, t0, t3                                   */
> >>> +        0x314C000C,   /* andi    t4, t2, 0xc      #node id                    */
> >>> +        0x000C62BC,   /* dsll    t4, 42                                       */
> >>> +        0x010C4025,   /* or      t0, t0, t4                                   */
> >>> +                      /* WaitForInit:                                         */
> >>> +        0xDD020020,   /* ld      v0, FN_OFF(t0)   #FN_OFF 0x020               */
> >>> +        0x1040FFFE,   /* beqz    v0, WaitForInit                              */
> >>> +        0x00000000,   /* nop                                                  */
> >>> +        0xDD1D0028,   /* ld      sp, SP_OFF(t0)   #FN_OFF 0x028               */
> >>> +        0xDD1C0030,   /* ld      gp, GP_OFF(t0)   #FN_OFF 0x030               */
> >>> +        0xDD050038,   /* ld      a1, A1_OFF(t0)   #FN_OFF 0x038               */
> >>> +        0x00400008,   /* jr      v0               #byebye                     */
> >>> +        0x00000000,   /* nop                                                  */
> >>> +        0x1000FFFF,   /* 1:  b   1b                                           */
> >>> +        0x00000000,   /* nop                                                  */
> >>> +
> >>> +                      /* Reset                                                */
> >>> +        0x3C0C9000,   /* dli     t0, 0x9000000010080010                       */
> >>> +        0x358C0000,
> >>> +        0x000C6438,
> >>> +        0x358C1008,
> >>> +        0x000C6438,
> >>> +        0x358C0010,
> >>> +        0x240D0000,   /* li      t1, 0x00                                     */
> >>> +        0xA18D0000,   /* sb      t1, (t0)                                     */
> >>> +        0x1000FFFF,   /* 1:  b   1b                                           */
> >>> +        0x00000000,   /* nop                                                  */
> >>> +
> >>> +                      /* Shutdown                                             */
> >>> +        0x3C0C9000,   /* dli     t0, 0x9000000010080010                       */
> >>> +        0x358C0000,
> >>> +        0x000C6438,
> >>> +        0x358C1008,
> >>> +        0x000C6438,
> >>> +        0x358C0010,
> >>> +        0x240D00FF,   /* li      t1, 0xff                                     */
> >>> +        0xA18D0000,   /* sb      t1, (t0)                                     */
> >>> +        0x1000FFFF,   /* 1:  b   1b                                           */
> >>> +        0x00000000    /* nop                                                  */
> >>> +    };
> >>> +
> >>> +    rom_add_blob_fixed("boot_rom", boot_code, sizeof(boot_code),
> >>> +                        loader_rommap[LOADER_BOOTROM].base);
> >>> +}
> >>> +
> >>> +static void fw_cfg_boot_set(void *opaque, const char *boot_device,
> >>> +                            Error **errp)
> >>> +{
> >>> +    fw_cfg_modify_i16(opaque, FW_CFG_BOOT_DEVICE, boot_device[0]);
> >>> +}
> >>> +
> >>> +static void fw_conf_init(unsigned long ram_size)
> >>> +{
> >>> +    FWCfgState *fw_cfg;
> >>> +    hwaddr cfg_addr = virt_memmap[VIRT_FW_CFG].base;
> >>> +
> >>> +    fw_cfg = fw_cfg_init_mem_wide(cfg_addr, cfg_addr + 8, 8, 0, NULL);
> >>> +    fw_cfg_add_i16(fw_cfg, FW_CFG_NB_CPUS, (uint16_t)current_machine->smp.cpus);
> >>> +    fw_cfg_add_i16(fw_cfg, FW_CFG_MAX_CPUS, (uint16_t)current_machine->smp.max_cpus);
> >>> +    fw_cfg_add_i64(fw_cfg, FW_CFG_RAM_SIZE, (uint64_t)ram_size);
> >>> +    fw_cfg_add_i32(fw_cfg, FW_CFG_MACHINE_VERSION, 1);
> >>> +    fw_cfg_add_i64(fw_cfg, FW_CFG_CPU_FREQ, get_cpu_freq());
> >>> +    qemu_register_boot_set(fw_cfg_boot_set, fw_cfg);
> >>> +}
> >>> +
> >>> +static int set_prom_cmdline(ram_addr_t initrd_offset, long initrd_size)
> >>> +{
> >>> +    hwaddr cmdline_vaddr;
> >>> +    char memenv[32];
> >>> +    char highmemenv[32];
> >>> +    void *cmdline_buf;
> >>> +    unsigned int *parg_env;
> >>> +    int ret = 0;
> >>> +
> >>> +    /* Allocate cmdline_buf for command line. */
> >>> +    cmdline_buf = g_malloc0(loader_memmap[LOADER_CMDLINE].size);
> >>> +    cmdline_vaddr = cpu_mips_phys_to_kseg0(NULL,
> >>> +                                           loader_memmap[LOADER_CMDLINE].base);
> >>> +
> >>> +    /*
> >>> +     * Layout of cmdline_buf looks like this:
> >>> +     * argv[0], argv[1], 0, env[0], env[1], ... env[i], 0,
> >>> +     * argv[0]'s data, argv[1]'s data, env[0]'data, ..., env[i]'s data, 0
> >>> +     */
> >>> +    parg_env = (void *)cmdline_buf;
> >>> +
> >>> +    ret = (3 + 1) * 4;
> >>> +    *parg_env++ = cmdline_vaddr + ret;
> >>> +    ret += (1 + snprintf(cmdline_buf + ret, 256 - ret, "g"));
> >>> +
> >>> +    /* argv1 */
> >>> +    *parg_env++ = cmdline_vaddr + ret;
> >>> +    if (initrd_size > 0)
> >>> +        ret += (1 + snprintf(cmdline_buf + ret, 256 - ret,
> >>> +                "rd_start=0x" TARGET_FMT_lx " rd_size=%li %s",
> >>> +                cpu_mips_phys_to_kseg0(NULL, initrd_offset),
> >>> +                initrd_size, loaderparams.kernel_cmdline));
> >>> +    else
> >>> +        ret += (1 + snprintf(cmdline_buf + ret, 256 - ret, "%s",
> >>> +                loaderparams.kernel_cmdline));
> >>> +
> >>> +    /* argv2 */
> >>> +    *parg_env++ = cmdline_vaddr + 4 * ret;
> >>> +
> >>> +    /* env */
> >>> +    sprintf(memenv, "%d", 256);
> >>> +    sprintf(highmemenv, "%ld", (unsigned long)(loaderparams.ram_size / MiB) - 256);
> >>> +
> >>> +    rom_add_blob_fixed("cmdline", cmdline_buf,
> >>> +                       loader_memmap[LOADER_CMDLINE].size,
> >>> +                       loader_memmap[LOADER_CMDLINE].base);
> >>> +
> >>> +    g_free(cmdline_buf);
> >>> +
> >>> +    loaderparams.a0 = 2;
> >>> +    loaderparams.a1 = cmdline_vaddr;
> >>> +
> >>> +    return 0;
> >>> +}
> >>> +
> >>> +static uint64_t load_kernel(CPUMIPSState *env)
> >>> +{
> >>> +    long kernel_size;
> >>> +    ram_addr_t initrd_offset;
> >>> +    uint64_t kernel_entry, kernel_low, kernel_high, initrd_size;
> >>> +
> >>> +    kernel_size = load_elf(loaderparams.kernel_filename, NULL,
> >>> +                           cpu_mips_kseg0_to_phys, NULL,
> >>> +                           (uint64_t *)&kernel_entry,
> >>> +                           (uint64_t *)&kernel_low, (uint64_t *)&kernel_high,
> >>> +                           NULL, 0, EM_MIPS, 1, 0);
> >>> +    if (kernel_size < 0) {
> >>> +        error_report("could not load kernel '%s': %s",
> >>> +                     loaderparams.kernel_filename,
> >>> +                     load_elf_strerror(kernel_size));
> >>> +        exit(1);
> >>> +    }
> >>> +
> >>> +    /* load initrd */
> >>> +    initrd_size = 0;
> >>> +    initrd_offset = 0;
> >>> +    if (loaderparams.initrd_filename) {
> >>> +        initrd_size = get_image_size(loaderparams.initrd_filename);
> >>> +        if (initrd_size > 0) {
> >>> +            initrd_offset = (kernel_high + ~INITRD_PAGE_MASK) &
> >>> +                            INITRD_PAGE_MASK;
> >>> +            initrd_offset = MAX(initrd_offset,
> >>> +                                loader_memmap[LOADER_INITRD].base);
> >>> +
> >>> +            if (initrd_offset + initrd_size > ram_size) {
> >>> +                error_report("memory too small for initial ram disk '%s'",
> >>> +                             loaderparams.initrd_filename);
> >>> +                exit(1);
> >>> +            }
> >>> +
> >>> +            initrd_size = load_image_targphys(loaderparams.initrd_filename,
> >>> +                                              initrd_offset,
> >>> +                                              ram_size - initrd_offset);
> >>> +        }
> >>> +
> >>> +        if (initrd_size == (target_ulong) -1) {
> >>> +            error_report("could not load initial ram disk '%s'",
> >>> +                         loaderparams.initrd_filename);
> >>> +            exit(1);
> >>> +        }
> >>> +    }
> >>> +
> >>> +    /* Setup prom cmdline. */
> >>> +    set_prom_cmdline(initrd_offset, initrd_size);
> >>> +
> >>> +    return kernel_entry;
> >>> +}
> >>> +
> >>> +static void main_cpu_reset(void *opaque)
> >>> +{
> >>> +    MIPSCPU *cpu = opaque;
> >>> +    CPUMIPSState *env = &cpu->env;
> >>> +
> >>> +    cpu_reset(CPU(cpu));
> >>> +
> >>> +    /* Loongson-3 reset stuff */
> >>> +    if (loaderparams.kernel_filename) {
> >>> +        if (cpu == MIPS_CPU(first_cpu)) {
> >>> +            env->active_tc.gpr[4] = loaderparams.a0;
> >>> +            env->active_tc.gpr[5] = loaderparams.a1;
> >>> +            env->active_tc.gpr[6] = loaderparams.a2;
> >>> +            env->active_tc.PC = loaderparams.kernel_entry;
> >>> +        }
> >>> +        env->CP0_Status &= ~((1 << CP0St_BEV) | (1 << CP0St_ERL));
> >>> +    }
> >>> +}
> >>> +
> >>> +static inline void loongson3_virt_devices_init(MachineState *machine, DeviceState *pic)
> >>> +{
> >>> +    int i;
> >>> +    qemu_irq irq;
> >>> +    PCIBus *pci_bus;
> >>> +    DeviceState *dev;
> >>> +    MemoryRegion *pio_alias;
> >>> +    MemoryRegion *mmio_alias, *mmio_reg;
> >>> +    MemoryRegion *ecam_alias, *ecam_reg;
> >>> +
> >>> +    dev = qdev_new(TYPE_GPEX_HOST);
> >>> +    sysbus_realize_and_unref(SYS_BUS_DEVICE(dev), &error_fatal);
> >>> +    pci_bus = PCI_HOST_BRIDGE(dev)->bus;
> >>> +
> >>> +    ecam_alias = g_new0(MemoryRegion, 1);
> >>> +    ecam_reg = sysbus_mmio_get_region(SYS_BUS_DEVICE(dev), 0);
> >>> +    memory_region_init_alias(ecam_alias, OBJECT(dev), "pcie-ecam",
> >>> +                             ecam_reg, 0, virt_memmap[VIRT_PCIE_ECAM].size);
> >>> +    memory_region_add_subregion(get_system_memory(),
> >>> +                                virt_memmap[VIRT_PCIE_ECAM].base, ecam_alias);
> >>> +
> >>> +    mmio_alias = g_new0(MemoryRegion, 1);
> >>> +    mmio_reg = sysbus_mmio_get_region(SYS_BUS_DEVICE(dev), 1);
> >>> +    memory_region_init_alias(mmio_alias, OBJECT(dev), "pcie-mmio",
> >>> +                             mmio_reg, virt_memmap[VIRT_PCIE_MMIO].base,
> >>> +                             virt_memmap[VIRT_PCIE_MMIO].size);
> >>> +    memory_region_add_subregion(get_system_memory(),
> >>> +                                virt_memmap[VIRT_PCIE_MMIO].base, mmio_alias);
> >>> +
> >>> +    pio_alias = g_new0(MemoryRegion, 1);
> >>> +    memory_region_init_alias(pio_alias, OBJECT(dev), "pcie-pio",
> >>> +                             get_system_io(), 0, virt_memmap[VIRT_PCIE_PIO].size);
> >>> +    memory_region_add_subregion(get_system_memory(),
> >>> +                                virt_memmap[VIRT_PCIE_PIO].base, pio_alias);
> >>> +    sysbus_mmio_map(SYS_BUS_DEVICE(dev), 2, virt_memmap[VIRT_PCIE_PIO].base);
> >>> +
> >>> +    for (i = 0; i < GPEX_NUM_IRQS; i++) {
> >>> +        irq = qdev_get_gpio_in(pic, PCIE_IRQ_BASE + i);
> >>> +        sysbus_connect_irq(SYS_BUS_DEVICE(dev), i, irq);
> >>> +        gpex_set_irq_num(GPEX_HOST(dev), i, PCIE_IRQ_BASE + i);
> >>> +    }
> >>> +
> >>> +    pci_vga_init(pci_bus);
> >>> +
> >>> +    if (defaults_enabled()) {
> >>> +        pci_create_simple(pci_bus, -1, "pci-ohci");
> >>> +        usb_create_simple(usb_bus_find(-1), "usb-kbd");
> >>> +        usb_create_simple(usb_bus_find(-1), "usb-tablet");
> >>> +    }
> >>> +
> >>> +    for (i = 0; i < nb_nics; i++) {
> >>> +        NICInfo *nd = &nd_table[i];
> >>> +
> >>> +        if (!nd->model) {
> >>> +            nd->model = g_strdup("virtio");
> >>> +        }
> >>> +
> >>> +        pci_nic_init_nofail(nd, pci_bus, nd->model, NULL);
> >>> +    }
> >>> +}
> >>> +
> >>> +static void mips_loongson3_virt_init(MachineState *machine)
> >>> +{
> >>> +    int i;
> >>> +    long bios_size;
> >>> +    MIPSCPU *cpu;
> >>> +    CPUMIPSState *env;
> >>> +    DeviceState *liointc;
> >>> +    char *filename;
> >>> +    const char *kernel_cmdline = machine->kernel_cmdline;
> >>> +    const char *kernel_filename = machine->kernel_filename;
> >>> +    const char *initrd_filename = machine->initrd_filename;
> >>> +    ram_addr_t ram_size = machine->ram_size;
> >>> +    MemoryRegion *address_space_mem = get_system_memory();
> >>> +    MemoryRegion *ram = g_new(MemoryRegion, 1);
> >>> +    MemoryRegion *bios = g_new(MemoryRegion, 1);
> >>> +    MemoryRegion *iomem = g_new(MemoryRegion, 1);
> >>> +
> >>> +    /* TODO: TCG will support all CPU types */
> >>> +    if (!kvm_enabled()) {
> >>> +        if (!machine->cpu_type) {
> >>> +            machine->cpu_type = MIPS_CPU_TYPE_NAME("Loongson-3A1000");
> >>> +        }
> >>> +        if (!strstr(machine->cpu_type, "Loongson-3A1000")) {
> >>> +            error_report("Loongson-3/TCG needs cpu type Loongson-3A1000");
> >>> +            exit(1);
> >>> +        }
> >>
> >> IIUC here you need to check machine->smp.cpus is 4 or 8 for the 3A1000.
> >> It would be easier if you model this as a qdev SoC, and this model
> >> cares to create the 4/8 cores (QEMU MIPSCPU).
> >>
> >> You defined max_cpu = LOONGSON_MAX_VCPUS = 16, this seems an impossible
> >> configuration for the 3A1000.
>  >
> > There are 4 cores in a SoC, but Loongson-3 support multi-sockets, more
> > than 4 vcpus will be treated as multi-sockets automatically in guests.
> > And current linux kernel also handle the case that only boot part of 4
> > cores in a socket.
>
> What I want to avoid is user booting the machine with 3 or 5 vCPUs,
> then complain booting Linux isn't working. It is simpler to check
> the number of vCPUs matches the hardware possibilities.
The upstream kernel can boot 3 or 5 cores on real hardware (reserve
several cores via boot parameters), so in virtual machine there is
also no problems to boot 3 or 5 vCPUs.

>
> >
> >>
> >>> +    } else {
> >>> +        if (!machine->cpu_type) {
> >>> +            machine->cpu_type = MIPS_CPU_TYPE_NAME("Loongson-3A4000");
> >>> +        }
> >>> +        if (!strstr(machine->cpu_type, "Loongson-3A4000")) {
> >>> +            error_report("Loongson-3/KVM needs cpu type Loongson-3A4000");
> >>> +            exit(1);
> >>> +        }
> >>
> >> Similar comment, as the 3A4000 is also a quad-core.
> >>
> >>> +    }
> >>> +
> >>> +    if (ram_size < 512 * MiB) {
> >>> +        error_report("Loongson-3 machine needs at least 512MB memory");
> >>> +        exit(1);
> >>> +    }
> >>> +
> >>> +    /*
> >>> +     * The whole MMIO range among configure registers doesn't generate
> >>> +     * exception when accessing invalid memory. Create an unimplememted
> >>> +     * device to emulate this feature.
> >>> +     */
> >>> +    create_unimplemented_device("fallback", 0x10000000, 0x30000000);
> >>
> >> The secondary crosswise switch description is hard to follow:
> >>
> >> * 2.4 Address routing distribution and configuration
> >>
> >> According  to  the  default  register  configuration,  CPU [...]
> >> 0x10000000-0x1fffffff  of  CPU  (256M)  is  mapped  to
> >> 0x10000000-0x1fffffff  of  PCI,  and  0x80000000  of  PCIDMA.
> >> In addition, when read access to illegal addresses occurs due to CPU
> >> guess execution, all 8 address Windows fail to hit, ?
> >>
> >> Table 2-9 XBAR level 2 default address configuration
> >>                     base                    high                     owner
> >> 0 x0000_0000_1000_0000  0 x0000_0000_2000_0000  Low speed I/O (PCI, etc)
> >>
> >> * 14.4 Secondary cross-switch address window
> >>
> >> After the address window is configured, the system address
> >> 0x0000_2000_0000 is added-- 0x0000_2FFFF_FFFF  maps  to
> >> 0x0000_0000_0000  -- 0x0000_0FFF_FFFF  of  memory  controller 0.An
> >> access to 0x0000_2000_0000 at this time will result in the original
> >> enabledThe value stored at address 0x0000_0000_0000.
> >>
> >> But see:
> >>
> >> * 14.6.3 Low speed device address window
> >>
> >> Here are defined the peripherals in the 0x1c00_0000-0x1ff0_ffff range.
> >>
> >> * 15.1 System memory space
> >>
> >> IO device, 0x1000_0000 --  0x1FFF_FFFF
> >>
> >> * 16 Memory allocation for system X
> >>
> >> ... divide  the  256M  PCI  space  (0x10000000~0x20000000)  into  two
> >> parts:  0x10000000~0x17ffffff for mem space and 0x18000000~0x20000000
> >> for IO space.
> >>
> >> I still don't understand what is in the 0x20000000-0x30000000 range.
> > Loongson's user manual is a little confusing, as a native Chinese I
> > also feel uncomfortable sometimes. :)
> > Generally speaking, Loongson-3's address space is configurable via
> > address windows, and the recommended configurations is like this:
> > 0x00000000-0x10000000   Low RAM
> > 0x10000000-0x40000000   ROM and MMIO Registers (such as BIOS_ROM at
> > 0x1fc00000, UART at 0x1fe001e0, LIOINTC at 0x3ff00140)
> > 0x40000000-0x80000000  PCI MEM
> > 0x80000000-TOM             High RAM
>
> Having a "fallback" region catching everything is not very helpful
> when debugging. Listing each unimplemented peripheral is more useful:
>
>    create_unimplemented_device("LPC MEM", 0x1c000000, 32 * MiB);
>    ...
>    create_unimplemented_device("UART1",   0x1fe001e8, 8);
>    create_unimplemented_device("SPI",     0x1fe001f0, 16);
>    create_unimplemented_device("LPC IO",  0x1ff00000, 64 * KiB);
>    ...
Catch everything here is because both host and guest use the same
kernel now, and there is some code try to access some address regions
which doesn't exist on virtual machine.

>
> >
> > PCI DMA of 0x10000000-0x1fffffff is a legacy region from
> > Loongson-2E/2F, and be cancelled in Loongson-3's configuration.
> > In real hardware, there should be a default "big enough" address
> > window to catch illegal address, return 0 for read access.
> > Yes, there is "nothing" in 0x20000000-0x30000000, because it is
> > undocumented which means "reserved for internal usage".
>
> If it is reserved, then the guest shouldn't be trying to use it...
OK, this will be improved, but create_uniplemented_device() for every
small region seems not good (see above).

>
> >>
> >>> +
> >>> +    liointc = qdev_new("loongson.liointc");
> >>> +    sysbus_realize_and_unref(SYS_BUS_DEVICE(liointc), &error_fatal);
> >>> +
> >>> +    sysbus_mmio_map(SYS_BUS_DEVICE(liointc), 0, virt_memmap[VIRT_LIOINTC].base);
> >>> +
> >>> +    for (i = 0; i < machine->smp.cpus; i++) {
> >>> +        int ip;
> >>> +
> >>> +        /* init CPUs */
> >>> +        cpu = MIPS_CPU(cpu_create(machine->cpu_type));
> >>> +
> >>> +        /* Init internal devices */
> >>> +        cpu_mips_irq_init_cpu(cpu);
> >>> +        cpu_mips_clock_init(cpu);
> >>> +        qemu_register_reset(main_cpu_reset, cpu);
> >>> +
> >>> +        if (i >= 4) {
> >>> +            continue; /* Only node-0 can be connected to LIOINTC */
> >>> +        }
> >>> +
> >>> +        for (ip = 0; ip < 4 ; ip++) {
> >>> +            int pin = i * 4 + ip;
> >>> +            sysbus_connect_irq(SYS_BUS_DEVICE(liointc),
> >>> +                               pin, cpu->env.irq[ip + 2]);
> >>> +        }
> >>> +    }
> >>> +    env = &MIPS_CPU(first_cpu)->env;
> >>> +
> >>> +    /* Allocate RAM/BIOS, 0x00000000~0x10000000 is alias of 0x80000000~0x90000000 */
> >>> +    memory_region_init_rom(bios, NULL, "loongson3.bios",
> >>> +                           virt_memmap[VIRT_BIOS_ROM].size, &error_fatal);
> >>> +    memory_region_init_alias(ram, NULL, "loongson3.lowmem",
> >>> +                           machine->ram, 0, virt_memmap[VIRT_LOWMEM].size);
> >>> +    memory_region_init_io(iomem, NULL, &loongson3_pm_ops,
> >>> +                           NULL, "loongson3_pm", virt_memmap[VIRT_PM].size);
> >>> +
> >>> +    memory_region_add_subregion(address_space_mem,
> >>> +                      virt_memmap[VIRT_LOWMEM].base, ram);
> >>> +    memory_region_add_subregion(address_space_mem,
> >>> +                      virt_memmap[VIRT_BIOS_ROM].base, bios);
> >>> +    memory_region_add_subregion(address_space_mem,
> >>> +                      virt_memmap[VIRT_HIGHMEM].base, machine->ram);
> >>> +    memory_region_add_subregion(address_space_mem,
> >>> +                      virt_memmap[VIRT_PM].base, iomem);
> >>> +
> >>> +    /*
> >>> +     * We do not support flash operation, just loading bios.bin as raw BIOS.
> >>> +     * Please use -L to set the BIOS path and -bios to set bios name.
> >>> +     */
> >>> +
> >>> +    if (kernel_filename) {
> >>> +        loaderparams.cpu_freq = get_cpu_freq();
> >>> +        loaderparams.ram_size = ram_size;
> >>> +        loaderparams.kernel_filename = kernel_filename;
> >>> +        loaderparams.kernel_cmdline = kernel_cmdline;
> >>> +        loaderparams.initrd_filename = initrd_filename;
> >>> +        loaderparams.kernel_entry = load_kernel(env);
> >>> +
> >>> +        init_boot_rom();
> >>> +        init_boot_param();
> >>> +    } else {
> >>> +        if (bios_name == NULL) {
> >>> +                bios_name = LOONGSON3_BIOSNAME;
> >>> +        }
> >>> +        filename = qemu_find_file(QEMU_FILE_TYPE_BIOS, bios_name);
> >>> +        if (filename) {
> >>> +            bios_size = load_image_targphys(filename,
> >>> +                                            virt_memmap[VIRT_BIOS_ROM].base,
> >>> +                                            virt_memmap[VIRT_BIOS_ROM].size);
> >>> +            g_free(filename);
> >>> +        } else {
> >>> +            bios_size = -1;
> >>> +        }
> >>> +
> >>> +        if ((bios_size < 0 || bios_size > virt_memmap[VIRT_BIOS_ROM].size) &&
> >>> +            !kernel_filename && !qtest_enabled()) {
> >>> +            error_report("Could not load MIPS bios '%s'", bios_name);
> >>> +            exit(1);
> >>> +        }
> >>> +
> >>> +        fw_conf_init(ram_size);
> >>> +    }
> >>> +
> >>> +    msi_nonbroken = true;
> >>> +    loongson3_virt_devices_init(machine, liointc);
> >>> +
> >>> +    sysbus_create_simple("goldfish_rtc", virt_memmap[VIRT_RTC].base,
> >>> +                         qdev_get_gpio_in(liointc, RTC_IRQ));
> >>> +
> >>> +    serial_mm_init(address_space_mem, virt_memmap[VIRT_UART].base, 0,
> >>> +                   qdev_get_gpio_in(liointc, UART_IRQ), 115200, serial_hd(0),
> >>> +                   DEVICE_NATIVE_ENDIAN);
> >>
> >> You need to split the SoC part from the machine part.
> > What do you mean? UART is SoC part and put it near LIOINTC?
>
> I understand the 3A4000 is a system-on-chip (SoC) with various
> peripherals (INTC, HT Bus, UART/SPI/I2C Ctrl, GPIO, Temp Sensors,
> DDR/ECC Ctrl, ...). Then the Godson-3 is the CPU unit,
> embedding the various GS464V cores.
>
> Maybe as:
>
>   +-------------------Machine-----------------+
>   |                                           |
>   | +--------------Loongson-3------------+    |
>   | |                                    |    |
>   | |  +------+Godson+3+----+  +----+    |    |
>   | |  |                    |  |TEMP|    |    |
>   | |  | +------+  +------+ |  +----+    |    |
>   | |  | |GS464V|  |GS464V| |            |    |
>   | |  | |=1vCPU|  |=1vCPU| |    +-------+    |
>   | |  | +------+  +------+ |    |       |    |
>   | |  |                    |    | GPIO  |    |
>   | |  | +------+  +------+ |    |       |    |
>   | |  | |GS464V|  |GS464V| |    +-------+    |
>   | |  | |=1vCPU|  |=1vCPU| |            |    |
>   | |  | +------+  +------+ |    +-------+    |
>   | |  |                    |    |       |    |
>   | |  +--------------------+    | LINTC |    |
>   | |                            |       |    |
>   | |                            +-------+    |
>   | |                                    |    |
>   | | +------+  +-----+  +-----+ +-----+ |    |
>   | | | UART |  | SPI |  | I2C | | ... | |    |
>   | +------------------------------------+    |
>   |                                           |
>   | +-------------+               +-------+   |
>   | |    DRAM     |               | FLASH |   |
>   | +-------------+               +-------+   |
>   +-------------------------------------------+
>
> QEMU tries to model each block as QOM.
>
> Anyway if you are happy with the current state,
> this can be improved later.
>
> >
> >>
> >>> +}
> >>> +
> >>> +static void mips_loongson3_virt_machine_init(MachineClass *mc)
> >>> +{
> >>> +    mc->desc = "Loongson-3 Virtualization Platform";
> >>> +    mc->init = mips_loongson3_virt_init;
> >>> +    mc->block_default_type = IF_IDE;
> >>
> >> Don't you need min_cpus = 4?
> > I think this is needn't.
>
> Well, you can not have a GS464V with 1 vCPU.
It is possible to boot a guest with 1 vCPU. :)

>
> >
> >>
> >>> +    mc->max_cpus = LOONGSON_MAX_VCPUS;
> >>> +    mc->default_ram_id = "loongson3.highram";
> >>> +    mc->default_ram_size = 1600 * MiB;
> >>> +    mc->kvm_type = mips_kvm_type;
> >>> +    mc->minimum_page_bits = 14;
> >>> +}
> >>> +
> >>> +DEFINE_MACHINE("loongson3-virt", mips_loongson3_virt_machine_init)
> >>> diff --git a/hw/mips/meson.build b/hw/mips/meson.build
> >>> index c98391c..72db43c 100644
> >>> --- a/hw/mips/meson.build
> >>> +++ b/hw/mips/meson.build
> >>> @@ -1,6 +1,7 @@
> >>>    mips_ss = ss.source_set()
> >>>    mips_ss.add(files('addr.c', 'mips_int.c', 'fw_cfg.c'))
> >>>    mips_ss.add(when: 'CONFIG_FULOONG', if_true: files('fuloong2e.c'))
> >>> +mips_ss.add(when: 'CONFIG_LOONGSON3V', if_true: files('loongson3_bootp.c', 'loongson3_virt.c'))
> >>>    mips_ss.add(when: 'CONFIG_JAZZ', if_true: files('jazz.c'))
> >>>    mips_ss.add(when: 'CONFIG_MALTA', if_true: files('gt64xxx_pci.c', 'malta.c'))
> >>>    mips_ss.add(when: 'CONFIG_MIPSSIM', if_true: files('mipssim.c'))
> >>>
> > Huacai
> >
Huacai
Philippe Mathieu-Daudé Oct. 13, 2020, 1:45 p.m. UTC | #5
On 10/13/20 1:12 PM, Huacai Chen wrote:
> Hi, Philippe,
> 
> On Mon, Oct 12, 2020 at 4:12 PM Philippe Mathieu-Daudé <f4bug@amsat.org> wrote:
>>
>> On 10/11/20 4:53 AM, Huacai Chen wrote:
>>> Hi, Philippe,
>>>
>>> On Sat, Oct 10, 2020 at 5:09 PM Philippe Mathieu-Daudé <f4bug@amsat.org> wrote:
>>>>
>>>> Hi Huacai,
>>>>
>>>> On 10/7/20 10:39 AM, Huacai Chen wrote:
>>>>> Add Loongson-3 based machine support, it use liointc as the interrupt
>>>>> controler and use GPEX as the pci controller. Currently it can work with
>>>>> both TCG and KVM.
>>>>>
>>>>> As the machine model is not based on any exiting physical hardware, the
>>>>> name of the machine is "loongson3-virt". It may be superseded in future
>>>>> by a real machine model. If this happens, then a regular deprecation
>>>>> procedure shall occur for "loongson3-virt" machine.
>>>>>
>>>>> We now already have a full functional Linux kernel (based on Linux-5.4.x
>>>>> LTS, the kvm host side and guest side have both been upstream for Linux-
>>>>> 5.9, but Linux-5.9 has not been released yet) here:
>>>>>
>>>>> https://github.com/chenhuacai/linux
>>>>>
>>>>> Of course the upstream kernel is also usable (though it is "unstable"
>>>>> now):
>>>>>
>>>>> https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
>>>>>
>>>>> How to use QEMU/Loongson-3?
>>>>> 1, Download kernel source from the above URL;
>>>>> 2, Build a kernel with arch/mips/configs/loongson3_defconfig;
>>>>> 3, Boot a Loongson-3A4000 host with this kernel (for KVM mode);
>>>>> 4, Build QEMU-master with this patchset;
>>>>> 5, modprobe kvm (only necessary for KVM mode);
>>>>> 6, Use QEMU with TCG:
>>>>>           qemu-system-mips64el -M loongson3-virt,accel=tcg -cpu Loongson-3A1000 -kernel <path_to_kernel> -append ...
>>>>>       Use QEMU with KVM:
>>>>>           qemu-system-mips64el -M loongson3-virt,accel=kvm -cpu Loongson-3A4000 -kernel <path_to_kernel> -append ...
>>>>>
>>>>>       The "-cpu" parameter is optional here and QEMU will use the correct type for TCG/KVM automatically.
>>>>>
>>>>> Signed-off-by: Huacai Chen <chenhc@lemote.com>
>>>>> Co-developed-by: Jiaxun Yang <jiaxun.yang@flygoat.com>
>>>>> ---
>>>>>     default-configs/devices/mips64el-softmmu.mak |   1 +
>>>>>     hw/mips/Kconfig                              |  12 +
>>>>>     hw/mips/loongson3_bootp.c                    | 162 +++++++
>>>>>     hw/mips/loongson3_bootp.h                    | 225 ++++++++++
>>>>
>>>> In a previous version I asked if you could split the bootp* files
>>>> (firmware related) in a previous separate patch to ease the review
>>>> of the machine part.
>>   >
>>> In previous version you told me to split the fw_cfg to a separate
>>> patch, but split the efi-related helpers to seprate files (not to a
>>> patch). But anyway, I will split them to a patch in the next version.
>>
>> Sorry if I wasn't clear enough. It is very hard to review a patch
>> of more than 1000 lines of C code without loosing focus or missing
>> problems. It explains why big patches might stay unreviewed on the
>> list. If you can split in smaller logical units, it will be very
>> helpful.
>>
>> Peter Maydell rule of thumb is to keep patch below 200 lines.
>> This is a good limit.
>>
>>>
>>>>
>>>>>     hw/mips/loongson3_virt.c                     | 615 +++++++++++++++++++++++++++
>>>>>     hw/mips/meson.build                          |   1 +
>>>>>     6 files changed, 1016 insertions(+)
>>>> [...]
>>>>
>>>>> diff --git a/hw/mips/loongson3_virt.c b/hw/mips/loongson3_virt.c
>>>>> new file mode 100644
>>>>> index 0000000..4e573d6
>>>>> --- /dev/null
>>>>> +++ b/hw/mips/loongson3_virt.c
>>>>> @@ -0,0 +1,615 @@
>>>>> +/*
>>>>> + * Generic Loongson-3 Platform support
>>>>> + *
>>>>> + * Copyright (c) 2017-2020 Huacai Chen (chenhc@lemote.com)
>>>>> + * Copyright (c) 2017-2020 Jiaxun Yang <jiaxun.yang@flygoat.com>
>>>>> + *
>>>>> + * This program is free software: you can redistribute it and/or modify
>>>>> + * it under the terms of the GNU General Public License as published by
>>>>> + * the Free Software Foundation, either version 2 of the License, or
>>>>> + * (at your option) any later version.
>>>>> + *
>>>>> + * This program is distributed in the hope that it will be useful,
>>>>> + * but WITHOUT ANY WARRANTY; without even the implied warranty of
>>>>> + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
>>>>> + * GNU General Public License for more details.
>>>>> + *
>>>>> + * You should have received a copy of the GNU General Public License
>>>>> + * along with this program. If not, see <https://www.gnu.org/licenses/>.
>>>>> + */
>>>>> +
>>>>> +/*
>>>>> + * Generic virtualized PC Platform based on Loongson-3 CPU (MIPS64R2 with
>>>>> + * extensions, 800~2000MHz)
>>>>> + */
>>>>> +
>>>>> +#include "qemu/osdep.h"
>>>>> +#include "qemu-common.h"
>>>>> +#include "qemu/units.h"
>>>>> +#include "qemu/cutils.h"
>>>>> +#include "qapi/error.h"
>>>>> +#include "cpu.h"
>>>>> +#include "elf.h"
>>>>> +#include "kvm_mips.h"
>>>>> +#include "hw/boards.h"
>>>>> +#include "hw/char/serial.h"
>>>>> +#include "hw/mips/mips.h"
>>>>> +#include "hw/mips/cpudevs.h"
>>>>> +#include "hw/mips/fw_cfg.h"
>>>>> +#include "hw/mips/loongson3_bootp.h"
>>>>> +#include "hw/misc/unimp.h"
>>>>> +#include "hw/intc/i8259.h"
>>>>> +#include "hw/loader.h"
>>>>> +#include "hw/isa/superio.h"
>>>>> +#include "hw/pci/msi.h"
>>>>> +#include "hw/pci/pci.h"
>>>>> +#include "hw/pci/pci_host.h"
>>>>> +#include "hw/pci-host/gpex.h"
>>>>> +#include "hw/rtc/mc146818rtc.h"
>>>>> +#include "hw/usb.h"
>>>>> +#include "net/net.h"
>>>>> +#include "exec/address-spaces.h"
>>>>> +#include "sysemu/kvm.h"
>>>>> +#include "sysemu/qtest.h"
>>>>> +#include "sysemu/reset.h"
>>>>> +#include "sysemu/runstate.h"
>>>>> +#include "qemu/log.h"
>>>>> +#include "qemu/error-report.h"
>>>>> +
>>>>> +#define PM_CNTL_MODE          0x10
>>>>> +
>>>>> +#define LOONGSON_MAX_VCPUS      16
>>>>> +
>>>>> +#define LOONGSON3_BIOSNAME "bios_loongson3.bin"
>>>>
>>>> Where is that file?
>>   >
>>> I don't know the policy of QEMU's binary file, just put that in the
>>> roms directory?
>>
>> If this is a closed source binary, we reference the URL where it can
>> be downloaded accepting eventual EULA.
>> If it is open source, the project is added as submodule. QEMU then
>> provides a link to how to build the firmware, or if there is no such
>> documentation, buildsys machinery is added to QEMU to build to it
>> (see roms/Makefile).
> OK, now the firmware is close-source (maybe open source in future), so
> I will put an URL here.
> 
>>
>>>
>>>>
>>>>> +
>>>>> +#define UART_IRQ            0
>>>>> +#define RTC_IRQ             1
>>>>> +#define PCIE_IRQ_BASE       2
>>>>> +
>>>>> +const struct MemmapEntry virt_memmap[] = {
>>>>> +    [VIRT_LOWMEM] =      { 0x00000000,    0x10000000 },
>>>>> +    [VIRT_PM] =          { 0x10080000,         0x100 },
>>>>> +    [VIRT_FW_CFG] =      { 0x10080100,         0x100 },
>>>>> +    [VIRT_RTC] =         { 0x10081000,        0x1000 },
>>>>> +    [VIRT_PCIE_PIO] =    { 0x18000000,       0x80000 },
>>>>> +    [VIRT_PCIE_ECAM] =   { 0x1a000000,     0x2000000 },
>>>>> +    [VIRT_BIOS_ROM] =    { 0x1fc00000,      0x200000 },
>>>>> +    [VIRT_UART] =        { 0x1fe001e0,           0x8 },
>>>>
>>>> See below about this mapping.
>>>>
>>>>> +    [VIRT_LIOINTC] =     { 0x3ff01400,          0x64 },
>>>>> +    [VIRT_PCIE_MMIO] =   { 0x40000000,    0x40000000 },
>>>>> +    [VIRT_HIGHMEM] =     { 0x80000000,           0x0 }, /* Variable */
>>>>> +};
>>>>> +
>>>>> +static const struct MemmapEntry loader_memmap[] = {
>>>>> +    [LOADER_KERNEL] =    { 0x00000000,     0x4000000 },
>>>>> +    [LOADER_INITRD] =    { 0x04000000,           0x0 }, /* Variable */
>>>>> +    [LOADER_CMDLINE] =   { 0x0ff00000,      0x100000 },
>>>>> +};
>>>>> +
>>>>> +static const struct MemmapEntry loader_rommap[] = {
>>>>> +    [LOADER_BOOTROM] =   { 0x1fc00000,        0x1000 },
>>>>> +    [LOADER_PARAM] =     { 0x1fc01000,       0x10000 },
>>>>> +};
>>>>> +
>>>>> +static struct _loaderparams {
>>>>> +    uint64_t cpu_freq;
>>>>> +    uint64_t ram_size;
>>>>> +    const char *kernel_cmdline;
>>>>> +    const char *kernel_filename;
>>>>> +    const char *initrd_filename;
>>>>> +    uint64_t kernel_entry;
>>>>> +    uint64_t a0, a1, a2;
>>>>> +} loaderparams;
>>>>> +
>>>>> +static uint64_t loongson3_pm_read(void *opaque, hwaddr addr, unsigned size)
>>>>> +{
>>>>> +    return 0;
>>>>> +}
>>>>> +
>>>>> +static void loongson3_pm_write(void *opaque, hwaddr addr, uint64_t val, unsigned size)
>>>>> +{
>>>>> +    if (addr != PM_CNTL_MODE) {
>>>>> +        return;
>>>>> +    }
>>>>> +
>>>>> +    switch (val) {
>>>>> +    case 0x00:
>>>>> +        qemu_system_reset_request(SHUTDOWN_CAUSE_GUEST_RESET);
>>>>> +        return;
>>>>> +    case 0xff:
>>>>> +        qemu_system_shutdown_request(SHUTDOWN_CAUSE_GUEST_SHUTDOWN);
>>>>> +        return;
>>>>> +    default:
>>>>> +        return;
>>>>> +    }
>>>>> +}
>>>>> +
>>>>> +static const MemoryRegionOps loongson3_pm_ops = {
>>>>> +    .read  = loongson3_pm_read,
>>>>> +    .write = loongson3_pm_write,
>>>>> +    .endianness = DEVICE_NATIVE_ENDIAN,
>>>>> +};
>>>>> +
>>>>> +#define DEF_TCG_FREQ (200 * 1000 * 1000)
>>>>> +#define DEF_KVM_FREQ (1600 * 1000 * 1000)
>>>>> +
>>>>> +static uint64_t get_cpu_freq(void)
>>>>> +{
>>>>> +#ifdef CONFIG_KVM
>>>>> +    int ret;
>>>>> +    uint64_t freq;
>>>>> +    struct kvm_one_reg freq_reg = {
>>>>> +        .id = KVM_REG_MIPS_COUNT_HZ,
>>>>> +        .addr = (uintptr_t)(&freq)
>>>>> +    };
>>>>> +
>>>>> +    if (kvm_enabled()) {
>>>>> +        ret = kvm_vcpu_ioctl(first_cpu, KVM_GET_ONE_REG, &freq_reg);
>>>>> +        if (ret < 0) {
>>>>> +            return DEF_KVM_FREQ;
>>>>> +        }
>>>>> +        return freq * 2;
>>>>> +    } else {
>>>>> +        /*
>>>>> +         * TCG has a default CP0 Timer period 10 ns, which is 100MHz,
>>>>> +         * CPU frequency is defined as double of CP0 timer frequency.
>>>>> +         */
>>>>> +        return DEF_TCG_FREQ;
>>>>> +    }
>>>>> +#else
>>>>> +    return DEF_TCG_FREQ;
>>>>> +#endif
>>>>> +}
>>>>> +
>>>>> +static void init_boot_param(void)
>>>>> +{
>>>>> +    void *p;
>>>>> +    struct boot_params *bp;
>>>>> +
>>>>> +    p = g_malloc0(loader_rommap[LOADER_PARAM].size);
>>>>> +    bp = p;
>>>>> +
>>>>> +    stw_le_p(&bp->efi.smbios.vers, 1);
>>>>> +    init_reset_system(&(bp->reset_system));
>>>>> +    p += ROUND_UP(sizeof(struct boot_params), 64);
>>>>> +    init_loongson_params(&(bp->efi.smbios.lp), p,
>>>>> +                         loaderparams.cpu_freq, loaderparams.ram_size);
>>>>> +
>>>>> +    rom_add_blob_fixed("params_rom", bp,
>>>>> +                       loader_rommap[LOADER_PARAM].size,
>>>>> +                       loader_rommap[LOADER_PARAM].base);
>>>>> +
>>>>> +    g_free(bp);
>>>>> +
>>>>> +    loaderparams.a2 = cpu_mips_phys_to_kseg0(NULL, loader_rommap[LOADER_PARAM].base);
>>>>> +}
>>>>> +
>>>>> +static void init_boot_rom(void)
>>>>> +{
>>>>> +    const unsigned int boot_code[] = {
>>>>> +        0x40086000,   /* mfc0    t0, CP0_STATUS                               */
>>>>> +        0x240900E4,   /* li      t1, 0xe4         #set kx, sx, ux, erl        */
>>>>> +        0x01094025,   /* or      t0, t0, t1                                   */
>>>>> +        0x3C090040,   /* lui     t1, 0x40         #set bev                    */
>>>>> +        0x01094025,   /* or      t0, t0, t1                                   */
>>>>> +        0x40886000,   /* mtc0    t0, CP0_STATUS                               */
>>>>> +        0x00000000,
>>>>> +        0x40806800,   /* mtc0    zero, CP0_CAUSE                              */
>>>>> +        0x00000000,
>>>>> +        0x400A7801,   /* mfc0    t2, $15, 1                                   */
>>>>> +        0x314A00FF,   /* andi    t2, 0x0ff                                    */
>>>>> +        0x3C089000,   /* dli     t0, 0x900000003ff01000                       */
>>>>> +        0x00084438,
>>>>> +        0x35083FF0,
>>>>> +        0x00084438,
>>>>> +        0x35081000,
>>>>> +        0x314B0003,   /* andi    t3, t2, 0x3      #local cpuid                */
>>>>> +        0x000B5A00,   /* sll     t3, 8                                        */
>>>>> +        0x010B4025,   /* or      t0, t0, t3                                   */
>>>>> +        0x314C000C,   /* andi    t4, t2, 0xc      #node id                    */
>>>>> +        0x000C62BC,   /* dsll    t4, 42                                       */
>>>>> +        0x010C4025,   /* or      t0, t0, t4                                   */
>>>>> +                      /* WaitForInit:                                         */
>>>>> +        0xDD020020,   /* ld      v0, FN_OFF(t0)   #FN_OFF 0x020               */
>>>>> +        0x1040FFFE,   /* beqz    v0, WaitForInit                              */
>>>>> +        0x00000000,   /* nop                                                  */
>>>>> +        0xDD1D0028,   /* ld      sp, SP_OFF(t0)   #FN_OFF 0x028               */
>>>>> +        0xDD1C0030,   /* ld      gp, GP_OFF(t0)   #FN_OFF 0x030               */
>>>>> +        0xDD050038,   /* ld      a1, A1_OFF(t0)   #FN_OFF 0x038               */
>>>>> +        0x00400008,   /* jr      v0               #byebye                     */
>>>>> +        0x00000000,   /* nop                                                  */
>>>>> +        0x1000FFFF,   /* 1:  b   1b                                           */
>>>>> +        0x00000000,   /* nop                                                  */
>>>>> +
>>>>> +                      /* Reset                                                */
>>>>> +        0x3C0C9000,   /* dli     t0, 0x9000000010080010                       */
>>>>> +        0x358C0000,
>>>>> +        0x000C6438,
>>>>> +        0x358C1008,
>>>>> +        0x000C6438,
>>>>> +        0x358C0010,
>>>>> +        0x240D0000,   /* li      t1, 0x00                                     */
>>>>> +        0xA18D0000,   /* sb      t1, (t0)                                     */
>>>>> +        0x1000FFFF,   /* 1:  b   1b                                           */
>>>>> +        0x00000000,   /* nop                                                  */
>>>>> +
>>>>> +                      /* Shutdown                                             */
>>>>> +        0x3C0C9000,   /* dli     t0, 0x9000000010080010                       */
>>>>> +        0x358C0000,
>>>>> +        0x000C6438,
>>>>> +        0x358C1008,
>>>>> +        0x000C6438,
>>>>> +        0x358C0010,
>>>>> +        0x240D00FF,   /* li      t1, 0xff                                     */
>>>>> +        0xA18D0000,   /* sb      t1, (t0)                                     */
>>>>> +        0x1000FFFF,   /* 1:  b   1b                                           */
>>>>> +        0x00000000    /* nop                                                  */
>>>>> +    };
>>>>> +
>>>>> +    rom_add_blob_fixed("boot_rom", boot_code, sizeof(boot_code),
>>>>> +                        loader_rommap[LOADER_BOOTROM].base);
>>>>> +}
>>>>> +
>>>>> +static void fw_cfg_boot_set(void *opaque, const char *boot_device,
>>>>> +                            Error **errp)
>>>>> +{
>>>>> +    fw_cfg_modify_i16(opaque, FW_CFG_BOOT_DEVICE, boot_device[0]);
>>>>> +}
>>>>> +
>>>>> +static void fw_conf_init(unsigned long ram_size)
>>>>> +{
>>>>> +    FWCfgState *fw_cfg;
>>>>> +    hwaddr cfg_addr = virt_memmap[VIRT_FW_CFG].base;
>>>>> +
>>>>> +    fw_cfg = fw_cfg_init_mem_wide(cfg_addr, cfg_addr + 8, 8, 0, NULL);
>>>>> +    fw_cfg_add_i16(fw_cfg, FW_CFG_NB_CPUS, (uint16_t)current_machine->smp.cpus);
>>>>> +    fw_cfg_add_i16(fw_cfg, FW_CFG_MAX_CPUS, (uint16_t)current_machine->smp.max_cpus);
>>>>> +    fw_cfg_add_i64(fw_cfg, FW_CFG_RAM_SIZE, (uint64_t)ram_size);
>>>>> +    fw_cfg_add_i32(fw_cfg, FW_CFG_MACHINE_VERSION, 1);
>>>>> +    fw_cfg_add_i64(fw_cfg, FW_CFG_CPU_FREQ, get_cpu_freq());
>>>>> +    qemu_register_boot_set(fw_cfg_boot_set, fw_cfg);
>>>>> +}
>>>>> +
>>>>> +static int set_prom_cmdline(ram_addr_t initrd_offset, long initrd_size)
>>>>> +{
>>>>> +    hwaddr cmdline_vaddr;
>>>>> +    char memenv[32];
>>>>> +    char highmemenv[32];
>>>>> +    void *cmdline_buf;
>>>>> +    unsigned int *parg_env;
>>>>> +    int ret = 0;
>>>>> +
>>>>> +    /* Allocate cmdline_buf for command line. */
>>>>> +    cmdline_buf = g_malloc0(loader_memmap[LOADER_CMDLINE].size);
>>>>> +    cmdline_vaddr = cpu_mips_phys_to_kseg0(NULL,
>>>>> +                                           loader_memmap[LOADER_CMDLINE].base);
>>>>> +
>>>>> +    /*
>>>>> +     * Layout of cmdline_buf looks like this:
>>>>> +     * argv[0], argv[1], 0, env[0], env[1], ... env[i], 0,
>>>>> +     * argv[0]'s data, argv[1]'s data, env[0]'data, ..., env[i]'s data, 0
>>>>> +     */
>>>>> +    parg_env = (void *)cmdline_buf;
>>>>> +
>>>>> +    ret = (3 + 1) * 4;
>>>>> +    *parg_env++ = cmdline_vaddr + ret;
>>>>> +    ret += (1 + snprintf(cmdline_buf + ret, 256 - ret, "g"));
>>>>> +
>>>>> +    /* argv1 */
>>>>> +    *parg_env++ = cmdline_vaddr + ret;
>>>>> +    if (initrd_size > 0)
>>>>> +        ret += (1 + snprintf(cmdline_buf + ret, 256 - ret,
>>>>> +                "rd_start=0x" TARGET_FMT_lx " rd_size=%li %s",
>>>>> +                cpu_mips_phys_to_kseg0(NULL, initrd_offset),
>>>>> +                initrd_size, loaderparams.kernel_cmdline));
>>>>> +    else
>>>>> +        ret += (1 + snprintf(cmdline_buf + ret, 256 - ret, "%s",
>>>>> +                loaderparams.kernel_cmdline));
>>>>> +
>>>>> +    /* argv2 */
>>>>> +    *parg_env++ = cmdline_vaddr + 4 * ret;
>>>>> +
>>>>> +    /* env */
>>>>> +    sprintf(memenv, "%d", 256);
>>>>> +    sprintf(highmemenv, "%ld", (unsigned long)(loaderparams.ram_size / MiB) - 256);
>>>>> +
>>>>> +    rom_add_blob_fixed("cmdline", cmdline_buf,
>>>>> +                       loader_memmap[LOADER_CMDLINE].size,
>>>>> +                       loader_memmap[LOADER_CMDLINE].base);
>>>>> +
>>>>> +    g_free(cmdline_buf);
>>>>> +
>>>>> +    loaderparams.a0 = 2;
>>>>> +    loaderparams.a1 = cmdline_vaddr;
>>>>> +
>>>>> +    return 0;
>>>>> +}
>>>>> +
>>>>> +static uint64_t load_kernel(CPUMIPSState *env)
>>>>> +{
>>>>> +    long kernel_size;
>>>>> +    ram_addr_t initrd_offset;
>>>>> +    uint64_t kernel_entry, kernel_low, kernel_high, initrd_size;
>>>>> +
>>>>> +    kernel_size = load_elf(loaderparams.kernel_filename, NULL,
>>>>> +                           cpu_mips_kseg0_to_phys, NULL,
>>>>> +                           (uint64_t *)&kernel_entry,
>>>>> +                           (uint64_t *)&kernel_low, (uint64_t *)&kernel_high,
>>>>> +                           NULL, 0, EM_MIPS, 1, 0);
>>>>> +    if (kernel_size < 0) {
>>>>> +        error_report("could not load kernel '%s': %s",
>>>>> +                     loaderparams.kernel_filename,
>>>>> +                     load_elf_strerror(kernel_size));
>>>>> +        exit(1);
>>>>> +    }
>>>>> +
>>>>> +    /* load initrd */
>>>>> +    initrd_size = 0;
>>>>> +    initrd_offset = 0;
>>>>> +    if (loaderparams.initrd_filename) {
>>>>> +        initrd_size = get_image_size(loaderparams.initrd_filename);
>>>>> +        if (initrd_size > 0) {
>>>>> +            initrd_offset = (kernel_high + ~INITRD_PAGE_MASK) &
>>>>> +                            INITRD_PAGE_MASK;
>>>>> +            initrd_offset = MAX(initrd_offset,
>>>>> +                                loader_memmap[LOADER_INITRD].base);
>>>>> +
>>>>> +            if (initrd_offset + initrd_size > ram_size) {
>>>>> +                error_report("memory too small for initial ram disk '%s'",
>>>>> +                             loaderparams.initrd_filename);
>>>>> +                exit(1);
>>>>> +            }
>>>>> +
>>>>> +            initrd_size = load_image_targphys(loaderparams.initrd_filename,
>>>>> +                                              initrd_offset,
>>>>> +                                              ram_size - initrd_offset);
>>>>> +        }
>>>>> +
>>>>> +        if (initrd_size == (target_ulong) -1) {
>>>>> +            error_report("could not load initial ram disk '%s'",
>>>>> +                         loaderparams.initrd_filename);
>>>>> +            exit(1);
>>>>> +        }
>>>>> +    }
>>>>> +
>>>>> +    /* Setup prom cmdline. */
>>>>> +    set_prom_cmdline(initrd_offset, initrd_size);
>>>>> +
>>>>> +    return kernel_entry;
>>>>> +}
>>>>> +
>>>>> +static void main_cpu_reset(void *opaque)
>>>>> +{
>>>>> +    MIPSCPU *cpu = opaque;
>>>>> +    CPUMIPSState *env = &cpu->env;
>>>>> +
>>>>> +    cpu_reset(CPU(cpu));
>>>>> +
>>>>> +    /* Loongson-3 reset stuff */
>>>>> +    if (loaderparams.kernel_filename) {
>>>>> +        if (cpu == MIPS_CPU(first_cpu)) {
>>>>> +            env->active_tc.gpr[4] = loaderparams.a0;
>>>>> +            env->active_tc.gpr[5] = loaderparams.a1;
>>>>> +            env->active_tc.gpr[6] = loaderparams.a2;
>>>>> +            env->active_tc.PC = loaderparams.kernel_entry;
>>>>> +        }
>>>>> +        env->CP0_Status &= ~((1 << CP0St_BEV) | (1 << CP0St_ERL));
>>>>> +    }
>>>>> +}
>>>>> +
>>>>> +static inline void loongson3_virt_devices_init(MachineState *machine, DeviceState *pic)
>>>>> +{
>>>>> +    int i;
>>>>> +    qemu_irq irq;
>>>>> +    PCIBus *pci_bus;
>>>>> +    DeviceState *dev;
>>>>> +    MemoryRegion *pio_alias;
>>>>> +    MemoryRegion *mmio_alias, *mmio_reg;
>>>>> +    MemoryRegion *ecam_alias, *ecam_reg;
>>>>> +
>>>>> +    dev = qdev_new(TYPE_GPEX_HOST);
>>>>> +    sysbus_realize_and_unref(SYS_BUS_DEVICE(dev), &error_fatal);
>>>>> +    pci_bus = PCI_HOST_BRIDGE(dev)->bus;
>>>>> +
>>>>> +    ecam_alias = g_new0(MemoryRegion, 1);
>>>>> +    ecam_reg = sysbus_mmio_get_region(SYS_BUS_DEVICE(dev), 0);
>>>>> +    memory_region_init_alias(ecam_alias, OBJECT(dev), "pcie-ecam",
>>>>> +                             ecam_reg, 0, virt_memmap[VIRT_PCIE_ECAM].size);
>>>>> +    memory_region_add_subregion(get_system_memory(),
>>>>> +                                virt_memmap[VIRT_PCIE_ECAM].base, ecam_alias);
>>>>> +
>>>>> +    mmio_alias = g_new0(MemoryRegion, 1);
>>>>> +    mmio_reg = sysbus_mmio_get_region(SYS_BUS_DEVICE(dev), 1);
>>>>> +    memory_region_init_alias(mmio_alias, OBJECT(dev), "pcie-mmio",
>>>>> +                             mmio_reg, virt_memmap[VIRT_PCIE_MMIO].base,
>>>>> +                             virt_memmap[VIRT_PCIE_MMIO].size);
>>>>> +    memory_region_add_subregion(get_system_memory(),
>>>>> +                                virt_memmap[VIRT_PCIE_MMIO].base, mmio_alias);
>>>>> +
>>>>> +    pio_alias = g_new0(MemoryRegion, 1);
>>>>> +    memory_region_init_alias(pio_alias, OBJECT(dev), "pcie-pio",
>>>>> +                             get_system_io(), 0, virt_memmap[VIRT_PCIE_PIO].size);
>>>>> +    memory_region_add_subregion(get_system_memory(),
>>>>> +                                virt_memmap[VIRT_PCIE_PIO].base, pio_alias);
>>>>> +    sysbus_mmio_map(SYS_BUS_DEVICE(dev), 2, virt_memmap[VIRT_PCIE_PIO].base);
>>>>> +
>>>>> +    for (i = 0; i < GPEX_NUM_IRQS; i++) {
>>>>> +        irq = qdev_get_gpio_in(pic, PCIE_IRQ_BASE + i);
>>>>> +        sysbus_connect_irq(SYS_BUS_DEVICE(dev), i, irq);
>>>>> +        gpex_set_irq_num(GPEX_HOST(dev), i, PCIE_IRQ_BASE + i);
>>>>> +    }
>>>>> +
>>>>> +    pci_vga_init(pci_bus);
>>>>> +
>>>>> +    if (defaults_enabled()) {
>>>>> +        pci_create_simple(pci_bus, -1, "pci-ohci");
>>>>> +        usb_create_simple(usb_bus_find(-1), "usb-kbd");
>>>>> +        usb_create_simple(usb_bus_find(-1), "usb-tablet");
>>>>> +    }
>>>>> +
>>>>> +    for (i = 0; i < nb_nics; i++) {
>>>>> +        NICInfo *nd = &nd_table[i];
>>>>> +
>>>>> +        if (!nd->model) {
>>>>> +            nd->model = g_strdup("virtio");
>>>>> +        }
>>>>> +
>>>>> +        pci_nic_init_nofail(nd, pci_bus, nd->model, NULL);
>>>>> +    }
>>>>> +}
>>>>> +
>>>>> +static void mips_loongson3_virt_init(MachineState *machine)
>>>>> +{
>>>>> +    int i;
>>>>> +    long bios_size;
>>>>> +    MIPSCPU *cpu;
>>>>> +    CPUMIPSState *env;
>>>>> +    DeviceState *liointc;
>>>>> +    char *filename;
>>>>> +    const char *kernel_cmdline = machine->kernel_cmdline;
>>>>> +    const char *kernel_filename = machine->kernel_filename;
>>>>> +    const char *initrd_filename = machine->initrd_filename;
>>>>> +    ram_addr_t ram_size = machine->ram_size;
>>>>> +    MemoryRegion *address_space_mem = get_system_memory();
>>>>> +    MemoryRegion *ram = g_new(MemoryRegion, 1);
>>>>> +    MemoryRegion *bios = g_new(MemoryRegion, 1);
>>>>> +    MemoryRegion *iomem = g_new(MemoryRegion, 1);
>>>>> +
>>>>> +    /* TODO: TCG will support all CPU types */
>>>>> +    if (!kvm_enabled()) {
>>>>> +        if (!machine->cpu_type) {
>>>>> +            machine->cpu_type = MIPS_CPU_TYPE_NAME("Loongson-3A1000");
>>>>> +        }
>>>>> +        if (!strstr(machine->cpu_type, "Loongson-3A1000")) {
>>>>> +            error_report("Loongson-3/TCG needs cpu type Loongson-3A1000");
>>>>> +            exit(1);
>>>>> +        }
>>>>
>>>> IIUC here you need to check machine->smp.cpus is 4 or 8 for the 3A1000.
>>>> It would be easier if you model this as a qdev SoC, and this model
>>>> cares to create the 4/8 cores (QEMU MIPSCPU).
>>>>
>>>> You defined max_cpu = LOONGSON_MAX_VCPUS = 16, this seems an impossible
>>>> configuration for the 3A1000.
>>   >
>>> There are 4 cores in a SoC, but Loongson-3 support multi-sockets, more
>>> than 4 vcpus will be treated as multi-sockets automatically in guests.
>>> And current linux kernel also handle the case that only boot part of 4
>>> cores in a socket.
>>
>> What I want to avoid is user booting the machine with 3 or 5 vCPUs,
>> then complain booting Linux isn't working. It is simpler to check
>> the number of vCPUs matches the hardware possibilities.
 >
> The upstream kernel can boot 3 or 5 cores on real hardware (reserve
> several cores via boot parameters), so in virtual machine there is
> also no problems to boot 3 or 5 vCPUs.

So we have:

- emulate hw with TCG, boot with fw
   -> follow real hw, 1 socket must have 4 cores

- virtualize with KVM, boot kernel
   -> any number of vCPU

Other use cases?

> 
>>
>>>
>>>>
>>>>> +    } else {
>>>>> +        if (!machine->cpu_type) {
>>>>> +            machine->cpu_type = MIPS_CPU_TYPE_NAME("Loongson-3A4000");
>>>>> +        }
>>>>> +        if (!strstr(machine->cpu_type, "Loongson-3A4000")) {
>>>>> +            error_report("Loongson-3/KVM needs cpu type Loongson-3A4000");
>>>>> +            exit(1);
>>>>> +        }
>>>>
>>>> Similar comment, as the 3A4000 is also a quad-core.
>>>>
>>>>> +    }
>>>>> +
>>>>> +    if (ram_size < 512 * MiB) {
>>>>> +        error_report("Loongson-3 machine needs at least 512MB memory");
>>>>> +        exit(1);
>>>>> +    }
>>>>> +
>>>>> +    /*
>>>>> +     * The whole MMIO range among configure registers doesn't generate
>>>>> +     * exception when accessing invalid memory. Create an unimplememted
>>>>> +     * device to emulate this feature.
>>>>> +     */
>>>>> +    create_unimplemented_device("fallback", 0x10000000, 0x30000000);
>>>>
>>>> The secondary crosswise switch description is hard to follow:
>>>>
>>>> * 2.4 Address routing distribution and configuration
>>>>
>>>> According  to  the  default  register  configuration,  CPU [...]
>>>> 0x10000000-0x1fffffff  of  CPU  (256M)  is  mapped  to
>>>> 0x10000000-0x1fffffff  of  PCI,  and  0x80000000  of  PCIDMA.
>>>> In addition, when read access to illegal addresses occurs due to CPU
>>>> guess execution, all 8 address Windows fail to hit, ?
>>>>
>>>> Table 2-9 XBAR level 2 default address configuration
>>>>                      base                    high                     owner
>>>> 0 x0000_0000_1000_0000  0 x0000_0000_2000_0000  Low speed I/O (PCI, etc)
>>>>
>>>> * 14.4 Secondary cross-switch address window
>>>>
>>>> After the address window is configured, the system address
>>>> 0x0000_2000_0000 is added-- 0x0000_2FFFF_FFFF  maps  to
>>>> 0x0000_0000_0000  -- 0x0000_0FFF_FFFF  of  memory  controller 0.An
>>>> access to 0x0000_2000_0000 at this time will result in the original
>>>> enabledThe value stored at address 0x0000_0000_0000.
>>>>
>>>> But see:
>>>>
>>>> * 14.6.3 Low speed device address window
>>>>
>>>> Here are defined the peripherals in the 0x1c00_0000-0x1ff0_ffff range.
>>>>
>>>> * 15.1 System memory space
>>>>
>>>> IO device, 0x1000_0000 --  0x1FFF_FFFF
>>>>
>>>> * 16 Memory allocation for system X
>>>>
>>>> ... divide  the  256M  PCI  space  (0x10000000~0x20000000)  into  two
>>>> parts:  0x10000000~0x17ffffff for mem space and 0x18000000~0x20000000
>>>> for IO space.
>>>>
>>>> I still don't understand what is in the 0x20000000-0x30000000 range.
>>> Loongson's user manual is a little confusing, as a native Chinese I
>>> also feel uncomfortable sometimes. :)
>>> Generally speaking, Loongson-3's address space is configurable via
>>> address windows, and the recommended configurations is like this:
>>> 0x00000000-0x10000000   Low RAM
>>> 0x10000000-0x40000000   ROM and MMIO Registers (such as BIOS_ROM at
>>> 0x1fc00000, UART at 0x1fe001e0, LIOINTC at 0x3ff00140)
>>> 0x40000000-0x80000000  PCI MEM
>>> 0x80000000-TOM             High RAM
>>
>> Having a "fallback" region catching everything is not very helpful
>> when debugging. Listing each unimplemented peripheral is more useful:
>>
>>     create_unimplemented_device("LPC MEM", 0x1c000000, 32 * MiB);
>>     ...
>>     create_unimplemented_device("UART1",   0x1fe001e8, 8);
>>     create_unimplemented_device("SPI",     0x1fe001f0, 16);
>>     create_unimplemented_device("LPC IO",  0x1ff00000, 64 * KiB);
>>     ...
> Catch everything here is because both host and guest use the same
> kernel now, and there is some code try to access some address regions
> which doesn't exist on virtual machine.

Why don't you want to start clean and create each unimp region?

> 
>>
>>>
>>> PCI DMA of 0x10000000-0x1fffffff is a legacy region from
>>> Loongson-2E/2F, and be cancelled in Loongson-3's configuration.
>>> In real hardware, there should be a default "big enough" address
>>> window to catch illegal address, return 0 for read access.
>>> Yes, there is "nothing" in 0x20000000-0x30000000, because it is
>>> undocumented which means "reserved for internal usage".
>>
>> If it is reserved, then the guest shouldn't be trying to use it...
> OK, this will be improved, but create_uniplemented_device() for every
> small region seems not good (see above).

"not good" -> why?
Huacai Chen Oct. 14, 2020, 1:28 a.m. UTC | #6
Hi, Philippe,

On Tue, Oct 13, 2020 at 9:45 PM Philippe Mathieu-Daudé <f4bug@amsat.org> wrote:
>
> On 10/13/20 1:12 PM, Huacai Chen wrote:
> > Hi, Philippe,
> >
> > On Mon, Oct 12, 2020 at 4:12 PM Philippe Mathieu-Daudé <f4bug@amsat.org> wrote:
> >>
> >> On 10/11/20 4:53 AM, Huacai Chen wrote:
> >>> Hi, Philippe,
> >>>
> >>> On Sat, Oct 10, 2020 at 5:09 PM Philippe Mathieu-Daudé <f4bug@amsat.org> wrote:
> >>>>
> >>>> Hi Huacai,
> >>>>
> >>>> On 10/7/20 10:39 AM, Huacai Chen wrote:
> >>>>> Add Loongson-3 based machine support, it use liointc as the interrupt
> >>>>> controler and use GPEX as the pci controller. Currently it can work with
> >>>>> both TCG and KVM.
> >>>>>
> >>>>> As the machine model is not based on any exiting physical hardware, the
> >>>>> name of the machine is "loongson3-virt". It may be superseded in future
> >>>>> by a real machine model. If this happens, then a regular deprecation
> >>>>> procedure shall occur for "loongson3-virt" machine.
> >>>>>
> >>>>> We now already have a full functional Linux kernel (based on Linux-5.4.x
> >>>>> LTS, the kvm host side and guest side have both been upstream for Linux-
> >>>>> 5.9, but Linux-5.9 has not been released yet) here:
> >>>>>
> >>>>> https://github.com/chenhuacai/linux
> >>>>>
> >>>>> Of course the upstream kernel is also usable (though it is "unstable"
> >>>>> now):
> >>>>>
> >>>>> https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
> >>>>>
> >>>>> How to use QEMU/Loongson-3?
> >>>>> 1, Download kernel source from the above URL;
> >>>>> 2, Build a kernel with arch/mips/configs/loongson3_defconfig;
> >>>>> 3, Boot a Loongson-3A4000 host with this kernel (for KVM mode);
> >>>>> 4, Build QEMU-master with this patchset;
> >>>>> 5, modprobe kvm (only necessary for KVM mode);
> >>>>> 6, Use QEMU with TCG:
> >>>>>           qemu-system-mips64el -M loongson3-virt,accel=tcg -cpu Loongson-3A1000 -kernel <path_to_kernel> -append ...
> >>>>>       Use QEMU with KVM:
> >>>>>           qemu-system-mips64el -M loongson3-virt,accel=kvm -cpu Loongson-3A4000 -kernel <path_to_kernel> -append ...
> >>>>>
> >>>>>       The "-cpu" parameter is optional here and QEMU will use the correct type for TCG/KVM automatically.
> >>>>>
> >>>>> Signed-off-by: Huacai Chen <chenhc@lemote.com>
> >>>>> Co-developed-by: Jiaxun Yang <jiaxun.yang@flygoat.com>
> >>>>> ---
> >>>>>     default-configs/devices/mips64el-softmmu.mak |   1 +
> >>>>>     hw/mips/Kconfig                              |  12 +
> >>>>>     hw/mips/loongson3_bootp.c                    | 162 +++++++
> >>>>>     hw/mips/loongson3_bootp.h                    | 225 ++++++++++
> >>>>
> >>>> In a previous version I asked if you could split the bootp* files
> >>>> (firmware related) in a previous separate patch to ease the review
> >>>> of the machine part.
> >>   >
> >>> In previous version you told me to split the fw_cfg to a separate
> >>> patch, but split the efi-related helpers to seprate files (not to a
> >>> patch). But anyway, I will split them to a patch in the next version.
> >>
> >> Sorry if I wasn't clear enough. It is very hard to review a patch
> >> of more than 1000 lines of C code without loosing focus or missing
> >> problems. It explains why big patches might stay unreviewed on the
> >> list. If you can split in smaller logical units, it will be very
> >> helpful.
> >>
> >> Peter Maydell rule of thumb is to keep patch below 200 lines.
> >> This is a good limit.
> >>
> >>>
> >>>>
> >>>>>     hw/mips/loongson3_virt.c                     | 615 +++++++++++++++++++++++++++
> >>>>>     hw/mips/meson.build                          |   1 +
> >>>>>     6 files changed, 1016 insertions(+)
> >>>> [...]
> >>>>
> >>>>> diff --git a/hw/mips/loongson3_virt.c b/hw/mips/loongson3_virt.c
> >>>>> new file mode 100644
> >>>>> index 0000000..4e573d6
> >>>>> --- /dev/null
> >>>>> +++ b/hw/mips/loongson3_virt.c
> >>>>> @@ -0,0 +1,615 @@
> >>>>> +/*
> >>>>> + * Generic Loongson-3 Platform support
> >>>>> + *
> >>>>> + * Copyright (c) 2017-2020 Huacai Chen (chenhc@lemote.com)
> >>>>> + * Copyright (c) 2017-2020 Jiaxun Yang <jiaxun.yang@flygoat.com>
> >>>>> + *
> >>>>> + * This program is free software: you can redistribute it and/or modify
> >>>>> + * it under the terms of the GNU General Public License as published by
> >>>>> + * the Free Software Foundation, either version 2 of the License, or
> >>>>> + * (at your option) any later version.
> >>>>> + *
> >>>>> + * This program is distributed in the hope that it will be useful,
> >>>>> + * but WITHOUT ANY WARRANTY; without even the implied warranty of
> >>>>> + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
> >>>>> + * GNU General Public License for more details.
> >>>>> + *
> >>>>> + * You should have received a copy of the GNU General Public License
> >>>>> + * along with this program. If not, see <https://www.gnu.org/licenses/>.
> >>>>> + */
> >>>>> +
> >>>>> +/*
> >>>>> + * Generic virtualized PC Platform based on Loongson-3 CPU (MIPS64R2 with
> >>>>> + * extensions, 800~2000MHz)
> >>>>> + */
> >>>>> +
> >>>>> +#include "qemu/osdep.h"
> >>>>> +#include "qemu-common.h"
> >>>>> +#include "qemu/units.h"
> >>>>> +#include "qemu/cutils.h"
> >>>>> +#include "qapi/error.h"
> >>>>> +#include "cpu.h"
> >>>>> +#include "elf.h"
> >>>>> +#include "kvm_mips.h"
> >>>>> +#include "hw/boards.h"
> >>>>> +#include "hw/char/serial.h"
> >>>>> +#include "hw/mips/mips.h"
> >>>>> +#include "hw/mips/cpudevs.h"
> >>>>> +#include "hw/mips/fw_cfg.h"
> >>>>> +#include "hw/mips/loongson3_bootp.h"
> >>>>> +#include "hw/misc/unimp.h"
> >>>>> +#include "hw/intc/i8259.h"
> >>>>> +#include "hw/loader.h"
> >>>>> +#include "hw/isa/superio.h"
> >>>>> +#include "hw/pci/msi.h"
> >>>>> +#include "hw/pci/pci.h"
> >>>>> +#include "hw/pci/pci_host.h"
> >>>>> +#include "hw/pci-host/gpex.h"
> >>>>> +#include "hw/rtc/mc146818rtc.h"
> >>>>> +#include "hw/usb.h"
> >>>>> +#include "net/net.h"
> >>>>> +#include "exec/address-spaces.h"
> >>>>> +#include "sysemu/kvm.h"
> >>>>> +#include "sysemu/qtest.h"
> >>>>> +#include "sysemu/reset.h"
> >>>>> +#include "sysemu/runstate.h"
> >>>>> +#include "qemu/log.h"
> >>>>> +#include "qemu/error-report.h"
> >>>>> +
> >>>>> +#define PM_CNTL_MODE          0x10
> >>>>> +
> >>>>> +#define LOONGSON_MAX_VCPUS      16
> >>>>> +
> >>>>> +#define LOONGSON3_BIOSNAME "bios_loongson3.bin"
> >>>>
> >>>> Where is that file?
> >>   >
> >>> I don't know the policy of QEMU's binary file, just put that in the
> >>> roms directory?
> >>
> >> If this is a closed source binary, we reference the URL where it can
> >> be downloaded accepting eventual EULA.
> >> If it is open source, the project is added as submodule. QEMU then
> >> provides a link to how to build the firmware, or if there is no such
> >> documentation, buildsys machinery is added to QEMU to build to it
> >> (see roms/Makefile).
> > OK, now the firmware is close-source (maybe open source in future), so
> > I will put an URL here.
> >
> >>
> >>>
> >>>>
> >>>>> +
> >>>>> +#define UART_IRQ            0
> >>>>> +#define RTC_IRQ             1
> >>>>> +#define PCIE_IRQ_BASE       2
> >>>>> +
> >>>>> +const struct MemmapEntry virt_memmap[] = {
> >>>>> +    [VIRT_LOWMEM] =      { 0x00000000,    0x10000000 },
> >>>>> +    [VIRT_PM] =          { 0x10080000,         0x100 },
> >>>>> +    [VIRT_FW_CFG] =      { 0x10080100,         0x100 },
> >>>>> +    [VIRT_RTC] =         { 0x10081000,        0x1000 },
> >>>>> +    [VIRT_PCIE_PIO] =    { 0x18000000,       0x80000 },
> >>>>> +    [VIRT_PCIE_ECAM] =   { 0x1a000000,     0x2000000 },
> >>>>> +    [VIRT_BIOS_ROM] =    { 0x1fc00000,      0x200000 },
> >>>>> +    [VIRT_UART] =        { 0x1fe001e0,           0x8 },
> >>>>
> >>>> See below about this mapping.
> >>>>
> >>>>> +    [VIRT_LIOINTC] =     { 0x3ff01400,          0x64 },
> >>>>> +    [VIRT_PCIE_MMIO] =   { 0x40000000,    0x40000000 },
> >>>>> +    [VIRT_HIGHMEM] =     { 0x80000000,           0x0 }, /* Variable */
> >>>>> +};
> >>>>> +
> >>>>> +static const struct MemmapEntry loader_memmap[] = {
> >>>>> +    [LOADER_KERNEL] =    { 0x00000000,     0x4000000 },
> >>>>> +    [LOADER_INITRD] =    { 0x04000000,           0x0 }, /* Variable */
> >>>>> +    [LOADER_CMDLINE] =   { 0x0ff00000,      0x100000 },
> >>>>> +};
> >>>>> +
> >>>>> +static const struct MemmapEntry loader_rommap[] = {
> >>>>> +    [LOADER_BOOTROM] =   { 0x1fc00000,        0x1000 },
> >>>>> +    [LOADER_PARAM] =     { 0x1fc01000,       0x10000 },
> >>>>> +};
> >>>>> +
> >>>>> +static struct _loaderparams {
> >>>>> +    uint64_t cpu_freq;
> >>>>> +    uint64_t ram_size;
> >>>>> +    const char *kernel_cmdline;
> >>>>> +    const char *kernel_filename;
> >>>>> +    const char *initrd_filename;
> >>>>> +    uint64_t kernel_entry;
> >>>>> +    uint64_t a0, a1, a2;
> >>>>> +} loaderparams;
> >>>>> +
> >>>>> +static uint64_t loongson3_pm_read(void *opaque, hwaddr addr, unsigned size)
> >>>>> +{
> >>>>> +    return 0;
> >>>>> +}
> >>>>> +
> >>>>> +static void loongson3_pm_write(void *opaque, hwaddr addr, uint64_t val, unsigned size)
> >>>>> +{
> >>>>> +    if (addr != PM_CNTL_MODE) {
> >>>>> +        return;
> >>>>> +    }
> >>>>> +
> >>>>> +    switch (val) {
> >>>>> +    case 0x00:
> >>>>> +        qemu_system_reset_request(SHUTDOWN_CAUSE_GUEST_RESET);
> >>>>> +        return;
> >>>>> +    case 0xff:
> >>>>> +        qemu_system_shutdown_request(SHUTDOWN_CAUSE_GUEST_SHUTDOWN);
> >>>>> +        return;
> >>>>> +    default:
> >>>>> +        return;
> >>>>> +    }
> >>>>> +}
> >>>>> +
> >>>>> +static const MemoryRegionOps loongson3_pm_ops = {
> >>>>> +    .read  = loongson3_pm_read,
> >>>>> +    .write = loongson3_pm_write,
> >>>>> +    .endianness = DEVICE_NATIVE_ENDIAN,
> >>>>> +};
> >>>>> +
> >>>>> +#define DEF_TCG_FREQ (200 * 1000 * 1000)
> >>>>> +#define DEF_KVM_FREQ (1600 * 1000 * 1000)
> >>>>> +
> >>>>> +static uint64_t get_cpu_freq(void)
> >>>>> +{
> >>>>> +#ifdef CONFIG_KVM
> >>>>> +    int ret;
> >>>>> +    uint64_t freq;
> >>>>> +    struct kvm_one_reg freq_reg = {
> >>>>> +        .id = KVM_REG_MIPS_COUNT_HZ,
> >>>>> +        .addr = (uintptr_t)(&freq)
> >>>>> +    };
> >>>>> +
> >>>>> +    if (kvm_enabled()) {
> >>>>> +        ret = kvm_vcpu_ioctl(first_cpu, KVM_GET_ONE_REG, &freq_reg);
> >>>>> +        if (ret < 0) {
> >>>>> +            return DEF_KVM_FREQ;
> >>>>> +        }
> >>>>> +        return freq * 2;
> >>>>> +    } else {
> >>>>> +        /*
> >>>>> +         * TCG has a default CP0 Timer period 10 ns, which is 100MHz,
> >>>>> +         * CPU frequency is defined as double of CP0 timer frequency.
> >>>>> +         */
> >>>>> +        return DEF_TCG_FREQ;
> >>>>> +    }
> >>>>> +#else
> >>>>> +    return DEF_TCG_FREQ;
> >>>>> +#endif
> >>>>> +}
> >>>>> +
> >>>>> +static void init_boot_param(void)
> >>>>> +{
> >>>>> +    void *p;
> >>>>> +    struct boot_params *bp;
> >>>>> +
> >>>>> +    p = g_malloc0(loader_rommap[LOADER_PARAM].size);
> >>>>> +    bp = p;
> >>>>> +
> >>>>> +    stw_le_p(&bp->efi.smbios.vers, 1);
> >>>>> +    init_reset_system(&(bp->reset_system));
> >>>>> +    p += ROUND_UP(sizeof(struct boot_params), 64);
> >>>>> +    init_loongson_params(&(bp->efi.smbios.lp), p,
> >>>>> +                         loaderparams.cpu_freq, loaderparams.ram_size);
> >>>>> +
> >>>>> +    rom_add_blob_fixed("params_rom", bp,
> >>>>> +                       loader_rommap[LOADER_PARAM].size,
> >>>>> +                       loader_rommap[LOADER_PARAM].base);
> >>>>> +
> >>>>> +    g_free(bp);
> >>>>> +
> >>>>> +    loaderparams.a2 = cpu_mips_phys_to_kseg0(NULL, loader_rommap[LOADER_PARAM].base);
> >>>>> +}
> >>>>> +
> >>>>> +static void init_boot_rom(void)
> >>>>> +{
> >>>>> +    const unsigned int boot_code[] = {
> >>>>> +        0x40086000,   /* mfc0    t0, CP0_STATUS                               */
> >>>>> +        0x240900E4,   /* li      t1, 0xe4         #set kx, sx, ux, erl        */
> >>>>> +        0x01094025,   /* or      t0, t0, t1                                   */
> >>>>> +        0x3C090040,   /* lui     t1, 0x40         #set bev                    */
> >>>>> +        0x01094025,   /* or      t0, t0, t1                                   */
> >>>>> +        0x40886000,   /* mtc0    t0, CP0_STATUS                               */
> >>>>> +        0x00000000,
> >>>>> +        0x40806800,   /* mtc0    zero, CP0_CAUSE                              */
> >>>>> +        0x00000000,
> >>>>> +        0x400A7801,   /* mfc0    t2, $15, 1                                   */
> >>>>> +        0x314A00FF,   /* andi    t2, 0x0ff                                    */
> >>>>> +        0x3C089000,   /* dli     t0, 0x900000003ff01000                       */
> >>>>> +        0x00084438,
> >>>>> +        0x35083FF0,
> >>>>> +        0x00084438,
> >>>>> +        0x35081000,
> >>>>> +        0x314B0003,   /* andi    t3, t2, 0x3      #local cpuid                */
> >>>>> +        0x000B5A00,   /* sll     t3, 8                                        */
> >>>>> +        0x010B4025,   /* or      t0, t0, t3                                   */
> >>>>> +        0x314C000C,   /* andi    t4, t2, 0xc      #node id                    */
> >>>>> +        0x000C62BC,   /* dsll    t4, 42                                       */
> >>>>> +        0x010C4025,   /* or      t0, t0, t4                                   */
> >>>>> +                      /* WaitForInit:                                         */
> >>>>> +        0xDD020020,   /* ld      v0, FN_OFF(t0)   #FN_OFF 0x020               */
> >>>>> +        0x1040FFFE,   /* beqz    v0, WaitForInit                              */
> >>>>> +        0x00000000,   /* nop                                                  */
> >>>>> +        0xDD1D0028,   /* ld      sp, SP_OFF(t0)   #FN_OFF 0x028               */
> >>>>> +        0xDD1C0030,   /* ld      gp, GP_OFF(t0)   #FN_OFF 0x030               */
> >>>>> +        0xDD050038,   /* ld      a1, A1_OFF(t0)   #FN_OFF 0x038               */
> >>>>> +        0x00400008,   /* jr      v0               #byebye                     */
> >>>>> +        0x00000000,   /* nop                                                  */
> >>>>> +        0x1000FFFF,   /* 1:  b   1b                                           */
> >>>>> +        0x00000000,   /* nop                                                  */
> >>>>> +
> >>>>> +                      /* Reset                                                */
> >>>>> +        0x3C0C9000,   /* dli     t0, 0x9000000010080010                       */
> >>>>> +        0x358C0000,
> >>>>> +        0x000C6438,
> >>>>> +        0x358C1008,
> >>>>> +        0x000C6438,
> >>>>> +        0x358C0010,
> >>>>> +        0x240D0000,   /* li      t1, 0x00                                     */
> >>>>> +        0xA18D0000,   /* sb      t1, (t0)                                     */
> >>>>> +        0x1000FFFF,   /* 1:  b   1b                                           */
> >>>>> +        0x00000000,   /* nop                                                  */
> >>>>> +
> >>>>> +                      /* Shutdown                                             */
> >>>>> +        0x3C0C9000,   /* dli     t0, 0x9000000010080010                       */
> >>>>> +        0x358C0000,
> >>>>> +        0x000C6438,
> >>>>> +        0x358C1008,
> >>>>> +        0x000C6438,
> >>>>> +        0x358C0010,
> >>>>> +        0x240D00FF,   /* li      t1, 0xff                                     */
> >>>>> +        0xA18D0000,   /* sb      t1, (t0)                                     */
> >>>>> +        0x1000FFFF,   /* 1:  b   1b                                           */
> >>>>> +        0x00000000    /* nop                                                  */
> >>>>> +    };
> >>>>> +
> >>>>> +    rom_add_blob_fixed("boot_rom", boot_code, sizeof(boot_code),
> >>>>> +                        loader_rommap[LOADER_BOOTROM].base);
> >>>>> +}
> >>>>> +
> >>>>> +static void fw_cfg_boot_set(void *opaque, const char *boot_device,
> >>>>> +                            Error **errp)
> >>>>> +{
> >>>>> +    fw_cfg_modify_i16(opaque, FW_CFG_BOOT_DEVICE, boot_device[0]);
> >>>>> +}
> >>>>> +
> >>>>> +static void fw_conf_init(unsigned long ram_size)
> >>>>> +{
> >>>>> +    FWCfgState *fw_cfg;
> >>>>> +    hwaddr cfg_addr = virt_memmap[VIRT_FW_CFG].base;
> >>>>> +
> >>>>> +    fw_cfg = fw_cfg_init_mem_wide(cfg_addr, cfg_addr + 8, 8, 0, NULL);
> >>>>> +    fw_cfg_add_i16(fw_cfg, FW_CFG_NB_CPUS, (uint16_t)current_machine->smp.cpus);
> >>>>> +    fw_cfg_add_i16(fw_cfg, FW_CFG_MAX_CPUS, (uint16_t)current_machine->smp.max_cpus);
> >>>>> +    fw_cfg_add_i64(fw_cfg, FW_CFG_RAM_SIZE, (uint64_t)ram_size);
> >>>>> +    fw_cfg_add_i32(fw_cfg, FW_CFG_MACHINE_VERSION, 1);
> >>>>> +    fw_cfg_add_i64(fw_cfg, FW_CFG_CPU_FREQ, get_cpu_freq());
> >>>>> +    qemu_register_boot_set(fw_cfg_boot_set, fw_cfg);
> >>>>> +}
> >>>>> +
> >>>>> +static int set_prom_cmdline(ram_addr_t initrd_offset, long initrd_size)
> >>>>> +{
> >>>>> +    hwaddr cmdline_vaddr;
> >>>>> +    char memenv[32];
> >>>>> +    char highmemenv[32];
> >>>>> +    void *cmdline_buf;
> >>>>> +    unsigned int *parg_env;
> >>>>> +    int ret = 0;
> >>>>> +
> >>>>> +    /* Allocate cmdline_buf for command line. */
> >>>>> +    cmdline_buf = g_malloc0(loader_memmap[LOADER_CMDLINE].size);
> >>>>> +    cmdline_vaddr = cpu_mips_phys_to_kseg0(NULL,
> >>>>> +                                           loader_memmap[LOADER_CMDLINE].base);
> >>>>> +
> >>>>> +    /*
> >>>>> +     * Layout of cmdline_buf looks like this:
> >>>>> +     * argv[0], argv[1], 0, env[0], env[1], ... env[i], 0,
> >>>>> +     * argv[0]'s data, argv[1]'s data, env[0]'data, ..., env[i]'s data, 0
> >>>>> +     */
> >>>>> +    parg_env = (void *)cmdline_buf;
> >>>>> +
> >>>>> +    ret = (3 + 1) * 4;
> >>>>> +    *parg_env++ = cmdline_vaddr + ret;
> >>>>> +    ret += (1 + snprintf(cmdline_buf + ret, 256 - ret, "g"));
> >>>>> +
> >>>>> +    /* argv1 */
> >>>>> +    *parg_env++ = cmdline_vaddr + ret;
> >>>>> +    if (initrd_size > 0)
> >>>>> +        ret += (1 + snprintf(cmdline_buf + ret, 256 - ret,
> >>>>> +                "rd_start=0x" TARGET_FMT_lx " rd_size=%li %s",
> >>>>> +                cpu_mips_phys_to_kseg0(NULL, initrd_offset),
> >>>>> +                initrd_size, loaderparams.kernel_cmdline));
> >>>>> +    else
> >>>>> +        ret += (1 + snprintf(cmdline_buf + ret, 256 - ret, "%s",
> >>>>> +                loaderparams.kernel_cmdline));
> >>>>> +
> >>>>> +    /* argv2 */
> >>>>> +    *parg_env++ = cmdline_vaddr + 4 * ret;
> >>>>> +
> >>>>> +    /* env */
> >>>>> +    sprintf(memenv, "%d", 256);
> >>>>> +    sprintf(highmemenv, "%ld", (unsigned long)(loaderparams.ram_size / MiB) - 256);
> >>>>> +
> >>>>> +    rom_add_blob_fixed("cmdline", cmdline_buf,
> >>>>> +                       loader_memmap[LOADER_CMDLINE].size,
> >>>>> +                       loader_memmap[LOADER_CMDLINE].base);
> >>>>> +
> >>>>> +    g_free(cmdline_buf);
> >>>>> +
> >>>>> +    loaderparams.a0 = 2;
> >>>>> +    loaderparams.a1 = cmdline_vaddr;
> >>>>> +
> >>>>> +    return 0;
> >>>>> +}
> >>>>> +
> >>>>> +static uint64_t load_kernel(CPUMIPSState *env)
> >>>>> +{
> >>>>> +    long kernel_size;
> >>>>> +    ram_addr_t initrd_offset;
> >>>>> +    uint64_t kernel_entry, kernel_low, kernel_high, initrd_size;
> >>>>> +
> >>>>> +    kernel_size = load_elf(loaderparams.kernel_filename, NULL,
> >>>>> +                           cpu_mips_kseg0_to_phys, NULL,
> >>>>> +                           (uint64_t *)&kernel_entry,
> >>>>> +                           (uint64_t *)&kernel_low, (uint64_t *)&kernel_high,
> >>>>> +                           NULL, 0, EM_MIPS, 1, 0);
> >>>>> +    if (kernel_size < 0) {
> >>>>> +        error_report("could not load kernel '%s': %s",
> >>>>> +                     loaderparams.kernel_filename,
> >>>>> +                     load_elf_strerror(kernel_size));
> >>>>> +        exit(1);
> >>>>> +    }
> >>>>> +
> >>>>> +    /* load initrd */
> >>>>> +    initrd_size = 0;
> >>>>> +    initrd_offset = 0;
> >>>>> +    if (loaderparams.initrd_filename) {
> >>>>> +        initrd_size = get_image_size(loaderparams.initrd_filename);
> >>>>> +        if (initrd_size > 0) {
> >>>>> +            initrd_offset = (kernel_high + ~INITRD_PAGE_MASK) &
> >>>>> +                            INITRD_PAGE_MASK;
> >>>>> +            initrd_offset = MAX(initrd_offset,
> >>>>> +                                loader_memmap[LOADER_INITRD].base);
> >>>>> +
> >>>>> +            if (initrd_offset + initrd_size > ram_size) {
> >>>>> +                error_report("memory too small for initial ram disk '%s'",
> >>>>> +                             loaderparams.initrd_filename);
> >>>>> +                exit(1);
> >>>>> +            }
> >>>>> +
> >>>>> +            initrd_size = load_image_targphys(loaderparams.initrd_filename,
> >>>>> +                                              initrd_offset,
> >>>>> +                                              ram_size - initrd_offset);
> >>>>> +        }
> >>>>> +
> >>>>> +        if (initrd_size == (target_ulong) -1) {
> >>>>> +            error_report("could not load initial ram disk '%s'",
> >>>>> +                         loaderparams.initrd_filename);
> >>>>> +            exit(1);
> >>>>> +        }
> >>>>> +    }
> >>>>> +
> >>>>> +    /* Setup prom cmdline. */
> >>>>> +    set_prom_cmdline(initrd_offset, initrd_size);
> >>>>> +
> >>>>> +    return kernel_entry;
> >>>>> +}
> >>>>> +
> >>>>> +static void main_cpu_reset(void *opaque)
> >>>>> +{
> >>>>> +    MIPSCPU *cpu = opaque;
> >>>>> +    CPUMIPSState *env = &cpu->env;
> >>>>> +
> >>>>> +    cpu_reset(CPU(cpu));
> >>>>> +
> >>>>> +    /* Loongson-3 reset stuff */
> >>>>> +    if (loaderparams.kernel_filename) {
> >>>>> +        if (cpu == MIPS_CPU(first_cpu)) {
> >>>>> +            env->active_tc.gpr[4] = loaderparams.a0;
> >>>>> +            env->active_tc.gpr[5] = loaderparams.a1;
> >>>>> +            env->active_tc.gpr[6] = loaderparams.a2;
> >>>>> +            env->active_tc.PC = loaderparams.kernel_entry;
> >>>>> +        }
> >>>>> +        env->CP0_Status &= ~((1 << CP0St_BEV) | (1 << CP0St_ERL));
> >>>>> +    }
> >>>>> +}
> >>>>> +
> >>>>> +static inline void loongson3_virt_devices_init(MachineState *machine, DeviceState *pic)
> >>>>> +{
> >>>>> +    int i;
> >>>>> +    qemu_irq irq;
> >>>>> +    PCIBus *pci_bus;
> >>>>> +    DeviceState *dev;
> >>>>> +    MemoryRegion *pio_alias;
> >>>>> +    MemoryRegion *mmio_alias, *mmio_reg;
> >>>>> +    MemoryRegion *ecam_alias, *ecam_reg;
> >>>>> +
> >>>>> +    dev = qdev_new(TYPE_GPEX_HOST);
> >>>>> +    sysbus_realize_and_unref(SYS_BUS_DEVICE(dev), &error_fatal);
> >>>>> +    pci_bus = PCI_HOST_BRIDGE(dev)->bus;
> >>>>> +
> >>>>> +    ecam_alias = g_new0(MemoryRegion, 1);
> >>>>> +    ecam_reg = sysbus_mmio_get_region(SYS_BUS_DEVICE(dev), 0);
> >>>>> +    memory_region_init_alias(ecam_alias, OBJECT(dev), "pcie-ecam",
> >>>>> +                             ecam_reg, 0, virt_memmap[VIRT_PCIE_ECAM].size);
> >>>>> +    memory_region_add_subregion(get_system_memory(),
> >>>>> +                                virt_memmap[VIRT_PCIE_ECAM].base, ecam_alias);
> >>>>> +
> >>>>> +    mmio_alias = g_new0(MemoryRegion, 1);
> >>>>> +    mmio_reg = sysbus_mmio_get_region(SYS_BUS_DEVICE(dev), 1);
> >>>>> +    memory_region_init_alias(mmio_alias, OBJECT(dev), "pcie-mmio",
> >>>>> +                             mmio_reg, virt_memmap[VIRT_PCIE_MMIO].base,
> >>>>> +                             virt_memmap[VIRT_PCIE_MMIO].size);
> >>>>> +    memory_region_add_subregion(get_system_memory(),
> >>>>> +                                virt_memmap[VIRT_PCIE_MMIO].base, mmio_alias);
> >>>>> +
> >>>>> +    pio_alias = g_new0(MemoryRegion, 1);
> >>>>> +    memory_region_init_alias(pio_alias, OBJECT(dev), "pcie-pio",
> >>>>> +                             get_system_io(), 0, virt_memmap[VIRT_PCIE_PIO].size);
> >>>>> +    memory_region_add_subregion(get_system_memory(),
> >>>>> +                                virt_memmap[VIRT_PCIE_PIO].base, pio_alias);
> >>>>> +    sysbus_mmio_map(SYS_BUS_DEVICE(dev), 2, virt_memmap[VIRT_PCIE_PIO].base);
> >>>>> +
> >>>>> +    for (i = 0; i < GPEX_NUM_IRQS; i++) {
> >>>>> +        irq = qdev_get_gpio_in(pic, PCIE_IRQ_BASE + i);
> >>>>> +        sysbus_connect_irq(SYS_BUS_DEVICE(dev), i, irq);
> >>>>> +        gpex_set_irq_num(GPEX_HOST(dev), i, PCIE_IRQ_BASE + i);
> >>>>> +    }
> >>>>> +
> >>>>> +    pci_vga_init(pci_bus);
> >>>>> +
> >>>>> +    if (defaults_enabled()) {
> >>>>> +        pci_create_simple(pci_bus, -1, "pci-ohci");
> >>>>> +        usb_create_simple(usb_bus_find(-1), "usb-kbd");
> >>>>> +        usb_create_simple(usb_bus_find(-1), "usb-tablet");
> >>>>> +    }
> >>>>> +
> >>>>> +    for (i = 0; i < nb_nics; i++) {
> >>>>> +        NICInfo *nd = &nd_table[i];
> >>>>> +
> >>>>> +        if (!nd->model) {
> >>>>> +            nd->model = g_strdup("virtio");
> >>>>> +        }
> >>>>> +
> >>>>> +        pci_nic_init_nofail(nd, pci_bus, nd->model, NULL);
> >>>>> +    }
> >>>>> +}
> >>>>> +
> >>>>> +static void mips_loongson3_virt_init(MachineState *machine)
> >>>>> +{
> >>>>> +    int i;
> >>>>> +    long bios_size;
> >>>>> +    MIPSCPU *cpu;
> >>>>> +    CPUMIPSState *env;
> >>>>> +    DeviceState *liointc;
> >>>>> +    char *filename;
> >>>>> +    const char *kernel_cmdline = machine->kernel_cmdline;
> >>>>> +    const char *kernel_filename = machine->kernel_filename;
> >>>>> +    const char *initrd_filename = machine->initrd_filename;
> >>>>> +    ram_addr_t ram_size = machine->ram_size;
> >>>>> +    MemoryRegion *address_space_mem = get_system_memory();
> >>>>> +    MemoryRegion *ram = g_new(MemoryRegion, 1);
> >>>>> +    MemoryRegion *bios = g_new(MemoryRegion, 1);
> >>>>> +    MemoryRegion *iomem = g_new(MemoryRegion, 1);
> >>>>> +
> >>>>> +    /* TODO: TCG will support all CPU types */
> >>>>> +    if (!kvm_enabled()) {
> >>>>> +        if (!machine->cpu_type) {
> >>>>> +            machine->cpu_type = MIPS_CPU_TYPE_NAME("Loongson-3A1000");
> >>>>> +        }
> >>>>> +        if (!strstr(machine->cpu_type, "Loongson-3A1000")) {
> >>>>> +            error_report("Loongson-3/TCG needs cpu type Loongson-3A1000");
> >>>>> +            exit(1);
> >>>>> +        }
> >>>>
> >>>> IIUC here you need to check machine->smp.cpus is 4 or 8 for the 3A1000.
> >>>> It would be easier if you model this as a qdev SoC, and this model
> >>>> cares to create the 4/8 cores (QEMU MIPSCPU).
> >>>>
> >>>> You defined max_cpu = LOONGSON_MAX_VCPUS = 16, this seems an impossible
> >>>> configuration for the 3A1000.
> >>   >
> >>> There are 4 cores in a SoC, but Loongson-3 support multi-sockets, more
> >>> than 4 vcpus will be treated as multi-sockets automatically in guests.
> >>> And current linux kernel also handle the case that only boot part of 4
> >>> cores in a socket.
> >>
> >> What I want to avoid is user booting the machine with 3 or 5 vCPUs,
> >> then complain booting Linux isn't working. It is simpler to check
> >> the number of vCPUs matches the hardware possibilities.
>  >
> > The upstream kernel can boot 3 or 5 cores on real hardware (reserve
> > several cores via boot parameters), so in virtual machine there is
> > also no problems to boot 3 or 5 vCPUs.
>
> So we have:
>
> - emulate hw with TCG, boot with fw
>    -> follow real hw, 1 socket must have 4 cores
>
> - virtualize with KVM, boot kernel
>    -> any number of vCPU
>
> Other use cases?
"How many cores a socket have" need not be the same as "how many cores
we boot", both for real hardware and virtual machines. Though the
"standard configuration" of Loongson-3A is 4 cores, there are some
real chips with hardware flaws. Our solution is to mask some cores in
hardware and modify the kernel to boot any number of cores (already
upstream since 3.17). So, our infrastructure already supports this, we
needn't limit anything.

>
> >
> >>
> >>>
> >>>>
> >>>>> +    } else {
> >>>>> +        if (!machine->cpu_type) {
> >>>>> +            machine->cpu_type = MIPS_CPU_TYPE_NAME("Loongson-3A4000");
> >>>>> +        }
> >>>>> +        if (!strstr(machine->cpu_type, "Loongson-3A4000")) {
> >>>>> +            error_report("Loongson-3/KVM needs cpu type Loongson-3A4000");
> >>>>> +            exit(1);
> >>>>> +        }
> >>>>
> >>>> Similar comment, as the 3A4000 is also a quad-core.
> >>>>
> >>>>> +    }
> >>>>> +
> >>>>> +    if (ram_size < 512 * MiB) {
> >>>>> +        error_report("Loongson-3 machine needs at least 512MB memory");
> >>>>> +        exit(1);
> >>>>> +    }
> >>>>> +
> >>>>> +    /*
> >>>>> +     * The whole MMIO range among configure registers doesn't generate
> >>>>> +     * exception when accessing invalid memory. Create an unimplememted
> >>>>> +     * device to emulate this feature.
> >>>>> +     */
> >>>>> +    create_unimplemented_device("fallback", 0x10000000, 0x30000000);
> >>>>
> >>>> The secondary crosswise switch description is hard to follow:
> >>>>
> >>>> * 2.4 Address routing distribution and configuration
> >>>>
> >>>> According  to  the  default  register  configuration,  CPU [...]
> >>>> 0x10000000-0x1fffffff  of  CPU  (256M)  is  mapped  to
> >>>> 0x10000000-0x1fffffff  of  PCI,  and  0x80000000  of  PCIDMA.
> >>>> In addition, when read access to illegal addresses occurs due to CPU
> >>>> guess execution, all 8 address Windows fail to hit, ?
> >>>>
> >>>> Table 2-9 XBAR level 2 default address configuration
> >>>>                      base                    high                     owner
> >>>> 0 x0000_0000_1000_0000  0 x0000_0000_2000_0000  Low speed I/O (PCI, etc)
> >>>>
> >>>> * 14.4 Secondary cross-switch address window
> >>>>
> >>>> After the address window is configured, the system address
> >>>> 0x0000_2000_0000 is added-- 0x0000_2FFFF_FFFF  maps  to
> >>>> 0x0000_0000_0000  -- 0x0000_0FFF_FFFF  of  memory  controller 0.An
> >>>> access to 0x0000_2000_0000 at this time will result in the original
> >>>> enabledThe value stored at address 0x0000_0000_0000.
> >>>>
> >>>> But see:
> >>>>
> >>>> * 14.6.3 Low speed device address window
> >>>>
> >>>> Here are defined the peripherals in the 0x1c00_0000-0x1ff0_ffff range.
> >>>>
> >>>> * 15.1 System memory space
> >>>>
> >>>> IO device, 0x1000_0000 --  0x1FFF_FFFF
> >>>>
> >>>> * 16 Memory allocation for system X
> >>>>
> >>>> ... divide  the  256M  PCI  space  (0x10000000~0x20000000)  into  two
> >>>> parts:  0x10000000~0x17ffffff for mem space and 0x18000000~0x20000000
> >>>> for IO space.
> >>>>
> >>>> I still don't understand what is in the 0x20000000-0x30000000 range.
> >>> Loongson's user manual is a little confusing, as a native Chinese I
> >>> also feel uncomfortable sometimes. :)
> >>> Generally speaking, Loongson-3's address space is configurable via
> >>> address windows, and the recommended configurations is like this:
> >>> 0x00000000-0x10000000   Low RAM
> >>> 0x10000000-0x40000000   ROM and MMIO Registers (such as BIOS_ROM at
> >>> 0x1fc00000, UART at 0x1fe001e0, LIOINTC at 0x3ff00140)
> >>> 0x40000000-0x80000000  PCI MEM
> >>> 0x80000000-TOM             High RAM
> >>
> >> Having a "fallback" region catching everything is not very helpful
> >> when debugging. Listing each unimplemented peripheral is more useful:
> >>
> >>     create_unimplemented_device("LPC MEM", 0x1c000000, 32 * MiB);
> >>     ...
> >>     create_unimplemented_device("UART1",   0x1fe001e8, 8);
> >>     create_unimplemented_device("SPI",     0x1fe001f0, 16);
> >>     create_unimplemented_device("LPC IO",  0x1ff00000, 64 * KiB);
> >>     ...
> > Catch everything here is because both host and guest use the same
> > kernel now, and there is some code try to access some address regions
> > which doesn't exist on virtual machine.
>
> Why don't you want to start clean and create each unimp region?
Let me explain the memory layout again:
0x00000000-0x10000000 256M low RAM
0x10000000-0x20000000 256M MMIO space 0
0x20000000-0x30000000 256M reserved
0x30000000-0x40000000 256M MMIO space 1
0x40000000-0x80000000 1G PCI MEM
0x80000000-TOM           high RAM

Now I realize that 0x20000000-0x30000000 should not be accessed by
software, so I want to change the code like this:
    create_unimplemented_device("mmio fallback 0", 0x10000000, 256 * MiB);
    create_unimplemented_device("mmio fallback 1", 0x30000000, 256 * MiB);

Then, why don't I want to create small regions? Because the MMIO space
contains something from SoC, and also something from peripheral
devices (mainly from the host bridge), this fact makes the detail
layout of MMIO space different from one real hardware to another real
hardware, and also different from real hardware to virtual machine.
So, a small region which holds a real device on a real machine may be
meaningless for the virtual machine, or meaningful but hold a
different virtual device (but we need to catch these addresses in
virtual machines, because real machines and virtual machines use the
same kernel, and some kernel code may unconditionally access these
addresses).

>
> >
> >>
> >>>
> >>> PCI DMA of 0x10000000-0x1fffffff is a legacy region from
> >>> Loongson-2E/2F, and be cancelled in Loongson-3's configuration.
> >>> In real hardware, there should be a default "big enough" address
> >>> window to catch illegal address, return 0 for read access.
> >>> Yes, there is "nothing" in 0x20000000-0x30000000, because it is
> >>> undocumented which means "reserved for internal usage".
> >>
> >> If it is reserved, then the guest shouldn't be trying to use it...
> > OK, this will be improved, but create_uniplemented_device() for every
> > small region seems not good (see above).
>
> "not good" -> why?
See above.

Huacai
diff mbox series

Patch

diff --git a/default-configs/devices/mips64el-softmmu.mak b/default-configs/devices/mips64el-softmmu.mak
index 9f8a3ef..26c660a 100644
--- a/default-configs/devices/mips64el-softmmu.mak
+++ b/default-configs/devices/mips64el-softmmu.mak
@@ -3,6 +3,7 @@ 
 include mips-softmmu-common.mak
 CONFIG_IDE_VIA=y
 CONFIG_FULOONG=y
+CONFIG_LOONGSON3V=y
 CONFIG_ATI_VGA=y
 CONFIG_RTL8139_PCI=y
 CONFIG_JAZZ=y
diff --git a/hw/mips/Kconfig b/hw/mips/Kconfig
index 67d39c5..6562b34 100644
--- a/hw/mips/Kconfig
+++ b/hw/mips/Kconfig
@@ -45,6 +45,18 @@  config FULOONG
     bool
     select PCI_BONITO
 
+config LOONGSON3V
+    bool
+    select PCKBD
+    select SERIAL
+    select GOLDFISH_RTC
+    select LOONGSON_LIOINTC
+    select PCI_DEVICES
+    select PCI_EXPRESS_GENERIC_BRIDGE
+    select VIRTIO_VGA
+    select QXL if SPICE
+    select MSI_NONBROKEN
+
 config MIPS_CPS
     bool
     select PTIMER
diff --git a/hw/mips/loongson3_bootp.c b/hw/mips/loongson3_bootp.c
new file mode 100644
index 0000000..1f11acf
--- /dev/null
+++ b/hw/mips/loongson3_bootp.c
@@ -0,0 +1,162 @@ 
+/*
+ * LEFI (a UEFI-like interface for BIOS-Kernel boot parameters) helpers
+ *
+ * Copyright (c) 2017-2020 Huacai Chen (chenhc@lemote.com)
+ * Copyright (c) 2017-2020 Jiaxun Yang <jiaxun.yang@flygoat.com>
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program. If not, see <https://www.gnu.org/licenses/>.
+ */
+
+#include "qemu/osdep.h"
+#include "qemu/units.h"
+#include "qemu/cutils.h"
+#include "cpu.h"
+#include "hw/boards.h"
+#include "hw/mips/loongson3_bootp.h"
+
+static struct efi_cpuinfo_loongson *init_cpu_info(void *g_cpuinfo, uint64_t cpu_freq)
+{
+    struct efi_cpuinfo_loongson *c = g_cpuinfo;
+
+    stl_le_p(&c->cputype, Loongson_3A);
+    stl_le_p(&c->processor_id, MIPS_CPU(first_cpu)->env.CP0_PRid);
+    if (cpu_freq > UINT_MAX) {
+        stl_le_p(&c->cpu_clock_freq, UINT_MAX);
+    } else {
+        stl_le_p(&c->cpu_clock_freq, cpu_freq);
+    }
+
+    stw_le_p(&c->cpu_startup_core_id, 0);
+    stl_le_p(&c->nr_cpus, current_machine->smp.cpus);
+    stl_le_p(&c->total_node, (current_machine->smp.cpus + 3) / 4);
+
+    return c;
+}
+
+static struct efi_memory_map_loongson *init_memory_map(void *g_map, uint64_t ram_size)
+{
+    struct efi_memory_map_loongson *emap = g_map;
+
+    stl_le_p(&emap->nr_map, 2);
+    stl_le_p(&emap->mem_freq, 300000000);
+
+    stl_le_p(&emap->map[0].node_id, 0);
+    stl_le_p(&emap->map[0].mem_type, 1);
+    stq_le_p(&emap->map[0].mem_start, 0x0);
+    stl_le_p(&emap->map[0].mem_size, 240);
+
+    stl_le_p(&emap->map[1].node_id, 0);
+    stl_le_p(&emap->map[1].mem_type, 2);
+    stq_le_p(&emap->map[1].mem_start, 0x90000000);
+    stl_le_p(&emap->map[1].mem_size, (ram_size / MiB) - 256);
+
+    return emap;
+}
+
+static struct system_loongson *init_system_loongson(void *g_system)
+{
+    struct system_loongson *s = g_system;
+
+    stl_le_p(&s->ccnuma_smp, 0);
+    stl_le_p(&s->sing_double_channel, 1);
+    stl_le_p(&s->nr_uarts, 1);
+    stl_le_p(&s->uarts[0].iotype, 2);
+    stl_le_p(&s->uarts[0].int_offset, 2);
+    stl_le_p(&s->uarts[0].uartclk, 25000000); /* Random value */
+    stq_le_p(&s->uarts[0].uart_base, virt_memmap[VIRT_UART].base);
+
+    return s;
+}
+
+static struct irq_source_routing_table *init_irq_source(void *g_irq_source)
+{
+    struct irq_source_routing_table *irq_info = g_irq_source;
+
+    stl_le_p(&irq_info->node_id, 0);
+    stl_le_p(&irq_info->PIC_type, 0);
+    stw_le_p(&irq_info->dma_mask_bits, 64);
+    stq_le_p(&irq_info->pci_mem_start_addr, virt_memmap[VIRT_PCIE_MMIO].base);
+    stq_le_p(&irq_info->pci_mem_end_addr, virt_memmap[VIRT_PCIE_MMIO].base +
+                                          virt_memmap[VIRT_PCIE_MMIO].size - 1);
+    stq_le_p(&irq_info->pci_io_start_addr, virt_memmap[VIRT_PCIE_PIO].base);
+
+    return irq_info;
+}
+
+static struct interface_info *init_interface_info(void *g_interface)
+{
+    struct interface_info *interface = g_interface;
+
+    stw_le_p(&interface->vers, 0x01);
+    strpadcpy(interface->description, 64, "UEFI_Version_v1.0", '\0');
+
+    return interface;
+}
+
+static struct board_devices *board_devices_info(void *g_board)
+{
+    struct board_devices *bd = g_board;
+
+    strpadcpy(bd->name, 64, "Loongson-3A-VIRT-1w-V1.00-demo", '\0');
+
+    return bd;
+}
+
+static struct loongson_special_attribute *init_special_info(void *g_special)
+{
+    struct loongson_special_attribute *special = g_special;
+
+    strpadcpy(special->special_name, 64, "2017-09-06", '\0');
+
+    return special;
+}
+
+void init_loongson_params(struct loongson_params *lp, void *p,
+                          uint64_t cpu_freq, uint64_t ram_size)
+{
+    stq_le_p(&lp->cpu_offset,
+              (uintptr_t)init_cpu_info(p, cpu_freq) - (uintptr_t)lp);
+    p += ROUND_UP(sizeof(struct efi_cpuinfo_loongson), 64);
+
+    stq_le_p(&lp->memory_offset,
+              (uintptr_t)init_memory_map(p, ram_size) - (uintptr_t)lp);
+    p += ROUND_UP(sizeof(struct efi_memory_map_loongson), 64);
+
+    stq_le_p(&lp->system_offset,
+              (uintptr_t)init_system_loongson(p) - (uintptr_t)lp);
+    p += ROUND_UP(sizeof(struct system_loongson), 64);
+
+    stq_le_p(&lp->irq_offset,
+              (uintptr_t)init_irq_source(p) - (uintptr_t)lp);
+    p += ROUND_UP(sizeof(struct irq_source_routing_table), 64);
+
+    stq_le_p(&lp->interface_offset,
+              (uintptr_t)init_interface_info(p) - (uintptr_t)lp);
+    p += ROUND_UP(sizeof(struct interface_info), 64);
+
+    stq_le_p(&lp->boarddev_table_offset,
+              (uintptr_t)board_devices_info(p) - (uintptr_t)lp);
+    p += ROUND_UP(sizeof(struct board_devices), 64);
+
+    stq_le_p(&lp->special_offset,
+              (uintptr_t)init_special_info(p) - (uintptr_t)lp);
+    p += ROUND_UP(sizeof(struct loongson_special_attribute), 64);
+}
+
+void init_reset_system(struct efi_reset_system_t *reset)
+{
+    stq_le_p(&reset->Shutdown, 0xffffffffbfc000a8);
+    stq_le_p(&reset->ResetCold, 0xffffffffbfc00080);
+    stq_le_p(&reset->ResetWarm, 0xffffffffbfc00080);
+}
diff --git a/hw/mips/loongson3_bootp.h b/hw/mips/loongson3_bootp.h
new file mode 100644
index 0000000..1edd736
--- /dev/null
+++ b/hw/mips/loongson3_bootp.h
@@ -0,0 +1,225 @@ 
+/*
+ * LEFI (a UEFI-like interface for BIOS-Kernel boot parameters) data structrues
+ * defined at arch/mips/include/asm/mach-loongson64/boot_param.h in Linux kernel
+ */
+
+#ifndef HW_MIPS_LOONGSON3_BOOTP_H
+#define HW_MIPS_LOONGSON3_BOOTP_H
+
+struct efi_memory_map_loongson {
+    uint16_t vers;               /* version of efi_memory_map */
+    uint32_t nr_map;             /* number of memory_maps */
+    uint32_t mem_freq;           /* memory frequence */
+    struct mem_map {
+        uint32_t node_id;        /* node_id which memory attached to */
+        uint32_t mem_type;       /* system memory, pci memory, pci io, etc. */
+        uint64_t mem_start;      /* memory map start address */
+        uint32_t mem_size;       /* each memory_map size, not the total size */
+    } map[128];
+} QEMU_PACKED;
+
+enum loongson_cpu_type {
+    Legacy_2E = 0x0,
+    Legacy_2F = 0x1,
+    Legacy_3A = 0x2,
+    Legacy_3B = 0x3,
+    Legacy_1A = 0x4,
+    Legacy_1B = 0x5,
+    Legacy_2G = 0x6,
+    Legacy_2H = 0x7,
+    Loongson_1A = 0x100,
+    Loongson_1B = 0x101,
+    Loongson_2E = 0x200,
+    Loongson_2F = 0x201,
+    Loongson_2G = 0x202,
+    Loongson_2H = 0x203,
+    Loongson_3A = 0x300,
+    Loongson_3B = 0x301
+};
+
+/*
+ * Capability and feature descriptor structure for MIPS CPU
+ */
+struct efi_cpuinfo_loongson {
+    uint16_t vers;               /* version of efi_cpuinfo_loongson */
+    uint32_t processor_id;       /* PRID, e.g. 6305, 6306 */
+    uint32_t cputype;            /* Loongson_3A/3B, etc. */
+    uint32_t total_node;         /* num of total numa nodes */
+    uint16_t cpu_startup_core_id;   /* Boot core id */
+    uint16_t reserved_cores_mask;
+    uint32_t cpu_clock_freq;     /* cpu_clock */
+    uint32_t nr_cpus;
+    char cpuname[64];
+} QEMU_PACKED;
+
+#define MAX_UARTS 64
+struct uart_device {
+    uint32_t iotype;
+    uint32_t uartclk;
+    uint32_t int_offset;
+    uint64_t uart_base;
+} QEMU_PACKED;
+
+#define MAX_SENSORS 64
+#define SENSOR_TEMPER  0x00000001
+#define SENSOR_VOLTAGE 0x00000002
+#define SENSOR_FAN     0x00000004
+struct sensor_device {
+    char name[32];  /* a formal name */
+    char label[64]; /* a flexible description */
+    uint32_t type;       /* SENSOR_* */
+    uint32_t id;         /* instance id of a sensor-class */
+    uint32_t fan_policy; /* step speed or constant speed */
+    uint32_t fan_percent;/* only for constant speed policy */
+    uint64_t base_addr;  /* base address of device registers */
+} QEMU_PACKED;
+
+struct system_loongson {
+    uint16_t vers;               /* version of system_loongson */
+    uint32_t ccnuma_smp;         /* 0: no numa; 1: has numa */
+    uint32_t sing_double_channel;/* 1: single; 2: double */
+    uint32_t nr_uarts;
+    struct uart_device uarts[MAX_UARTS];
+    uint32_t nr_sensors;
+    struct sensor_device sensors[MAX_SENSORS];
+    char has_ec;
+    char ec_name[32];
+    uint64_t ec_base_addr;
+    char has_tcm;
+    char tcm_name[32];
+    uint64_t tcm_base_addr;
+    uint64_t workarounds;
+    uint64_t of_dtb_addr; /* NULL if not support */
+} QEMU_PACKED;
+
+struct irq_source_routing_table {
+    uint16_t vers;
+    uint16_t size;
+    uint16_t rtr_bus;
+    uint16_t rtr_devfn;
+    uint32_t vendor;
+    uint32_t device;
+    uint32_t PIC_type;           /* conform use HT or PCI to route to CPU-PIC */
+    uint64_t ht_int_bit;         /* 3A: 1<<24; 3B: 1<<16 */
+    uint64_t ht_enable;          /* irqs used in this PIC */
+    uint32_t node_id;            /* node id: 0x0-0; 0x1-1; 0x10-2; 0x11-3 */
+    uint64_t pci_mem_start_addr;
+    uint64_t pci_mem_end_addr;
+    uint64_t pci_io_start_addr;
+    uint64_t pci_io_end_addr;
+    uint64_t pci_config_addr;
+    uint16_t dma_mask_bits;
+    uint16_t dma_noncoherent;
+} QEMU_PACKED;
+
+struct interface_info {
+    uint16_t vers;               /* version of the specificition */
+    uint16_t size;
+    uint8_t  flag;
+    char description[64];
+} QEMU_PACKED;
+
+#define MAX_RESOURCE_NUMBER 128
+struct resource_loongson {
+    uint64_t start;              /* resource start address */
+    uint64_t end;                /* resource end address */
+    char name[64];
+    uint32_t flags;
+};
+
+struct archdev_data {};          /* arch specific additions */
+
+struct board_devices {
+    char name[64];               /* hold the device name */
+    uint32_t num_resources;      /* number of device_resource */
+    /* for each device's resource */
+    struct resource_loongson resource[MAX_RESOURCE_NUMBER];
+    /* arch specific additions */
+    struct archdev_data archdata;
+};
+
+struct loongson_special_attribute {
+    uint16_t vers;               /* version of this special */
+    char special_name[64];       /* special_atribute_name */
+    uint32_t loongson_special_type; /* type of special device */
+    /* for each device's resource */
+    struct resource_loongson resource[MAX_RESOURCE_NUMBER];
+};
+
+struct loongson_params {
+    uint64_t memory_offset;      /* efi_memory_map_loongson struct offset */
+    uint64_t cpu_offset;         /* efi_cpuinfo_loongson struct offset */
+    uint64_t system_offset;      /* system_loongson struct offset */
+    uint64_t irq_offset;         /* irq_source_routing_table struct offset */
+    uint64_t interface_offset;   /* interface_info struct offset */
+    uint64_t special_offset;     /* loongson_special_attribute struct offset */
+    uint64_t boarddev_table_offset;  /* board_devices offset */
+};
+
+struct smbios_tables {
+    uint16_t vers;               /* version of smbios */
+    uint64_t vga_bios;           /* vga_bios address */
+    struct loongson_params lp;
+};
+
+struct efi_reset_system_t {
+    uint64_t ResetCold;
+    uint64_t ResetWarm;
+    uint64_t ResetType;
+    uint64_t Shutdown;
+    uint64_t DoSuspend; /* NULL if not support */
+};
+
+struct efi_loongson {
+    uint64_t mps;                /* MPS table */
+    uint64_t acpi;               /* ACPI table (IA64 ext 0.71) */
+    uint64_t acpi20;             /* ACPI table (ACPI 2.0) */
+    struct smbios_tables smbios; /* SM BIOS table */
+    uint64_t sal_systab;         /* SAL system table */
+    uint64_t boot_info;          /* boot info table */
+};
+
+struct boot_params {
+    struct efi_loongson efi;
+    struct efi_reset_system_t reset_system;
+};
+
+/* Overall MMIO & Memory layout */
+enum {
+    VIRT_LOWMEM,
+    VIRT_PM,
+    VIRT_FW_CFG,
+    VIRT_RTC,
+    VIRT_PCIE_PIO,
+    VIRT_PCIE_ECAM,
+    VIRT_BIOS_ROM,
+    VIRT_UART,
+    VIRT_LIOINTC,
+    VIRT_PCIE_MMIO,
+    VIRT_HIGHMEM
+};
+
+/* Low MEM layout for QEMU kernel loader */
+enum {
+    LOADER_KERNEL,
+    LOADER_INITRD,
+    LOADER_CMDLINE
+};
+
+/* BIOS ROM layout for QEMU kernel loader */
+enum {
+    LOADER_BOOTROM,
+    LOADER_PARAM,
+};
+
+struct MemmapEntry {
+    hwaddr base;
+    hwaddr size;
+};
+
+extern const struct MemmapEntry virt_memmap[];
+void init_loongson_params(struct loongson_params *lp, void *p,
+                          uint64_t cpu_freq, uint64_t ram_size);
+void init_reset_system(struct efi_reset_system_t *reset);
+
+#endif
diff --git a/hw/mips/loongson3_virt.c b/hw/mips/loongson3_virt.c
new file mode 100644
index 0000000..4e573d6
--- /dev/null
+++ b/hw/mips/loongson3_virt.c
@@ -0,0 +1,615 @@ 
+/*
+ * Generic Loongson-3 Platform support
+ *
+ * Copyright (c) 2017-2020 Huacai Chen (chenhc@lemote.com)
+ * Copyright (c) 2017-2020 Jiaxun Yang <jiaxun.yang@flygoat.com>
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program. If not, see <https://www.gnu.org/licenses/>.
+ */
+
+/*
+ * Generic virtualized PC Platform based on Loongson-3 CPU (MIPS64R2 with
+ * extensions, 800~2000MHz)
+ */
+
+#include "qemu/osdep.h"
+#include "qemu-common.h"
+#include "qemu/units.h"
+#include "qemu/cutils.h"
+#include "qapi/error.h"
+#include "cpu.h"
+#include "elf.h"
+#include "kvm_mips.h"
+#include "hw/boards.h"
+#include "hw/char/serial.h"
+#include "hw/mips/mips.h"
+#include "hw/mips/cpudevs.h"
+#include "hw/mips/fw_cfg.h"
+#include "hw/mips/loongson3_bootp.h"
+#include "hw/misc/unimp.h"
+#include "hw/intc/i8259.h"
+#include "hw/loader.h"
+#include "hw/isa/superio.h"
+#include "hw/pci/msi.h"
+#include "hw/pci/pci.h"
+#include "hw/pci/pci_host.h"
+#include "hw/pci-host/gpex.h"
+#include "hw/rtc/mc146818rtc.h"
+#include "hw/usb.h"
+#include "net/net.h"
+#include "exec/address-spaces.h"
+#include "sysemu/kvm.h"
+#include "sysemu/qtest.h"
+#include "sysemu/reset.h"
+#include "sysemu/runstate.h"
+#include "qemu/log.h"
+#include "qemu/error-report.h"
+
+#define PM_CNTL_MODE          0x10
+
+#define LOONGSON_MAX_VCPUS      16
+
+#define LOONGSON3_BIOSNAME "bios_loongson3.bin"
+
+#define UART_IRQ            0
+#define RTC_IRQ             1
+#define PCIE_IRQ_BASE       2
+
+const struct MemmapEntry virt_memmap[] = {
+    [VIRT_LOWMEM] =      { 0x00000000,    0x10000000 },
+    [VIRT_PM] =          { 0x10080000,         0x100 },
+    [VIRT_FW_CFG] =      { 0x10080100,         0x100 },
+    [VIRT_RTC] =         { 0x10081000,        0x1000 },
+    [VIRT_PCIE_PIO] =    { 0x18000000,       0x80000 },
+    [VIRT_PCIE_ECAM] =   { 0x1a000000,     0x2000000 },
+    [VIRT_BIOS_ROM] =    { 0x1fc00000,      0x200000 },
+    [VIRT_UART] =        { 0x1fe001e0,           0x8 },
+    [VIRT_LIOINTC] =     { 0x3ff01400,          0x64 },
+    [VIRT_PCIE_MMIO] =   { 0x40000000,    0x40000000 },
+    [VIRT_HIGHMEM] =     { 0x80000000,           0x0 }, /* Variable */
+};
+
+static const struct MemmapEntry loader_memmap[] = {
+    [LOADER_KERNEL] =    { 0x00000000,     0x4000000 },
+    [LOADER_INITRD] =    { 0x04000000,           0x0 }, /* Variable */
+    [LOADER_CMDLINE] =   { 0x0ff00000,      0x100000 },
+};
+
+static const struct MemmapEntry loader_rommap[] = {
+    [LOADER_BOOTROM] =   { 0x1fc00000,        0x1000 },
+    [LOADER_PARAM] =     { 0x1fc01000,       0x10000 },
+};
+
+static struct _loaderparams {
+    uint64_t cpu_freq;
+    uint64_t ram_size;
+    const char *kernel_cmdline;
+    const char *kernel_filename;
+    const char *initrd_filename;
+    uint64_t kernel_entry;
+    uint64_t a0, a1, a2;
+} loaderparams;
+
+static uint64_t loongson3_pm_read(void *opaque, hwaddr addr, unsigned size)
+{
+    return 0;
+}
+
+static void loongson3_pm_write(void *opaque, hwaddr addr, uint64_t val, unsigned size)
+{
+    if (addr != PM_CNTL_MODE) {
+        return;
+    }
+
+    switch (val) {
+    case 0x00:
+        qemu_system_reset_request(SHUTDOWN_CAUSE_GUEST_RESET);
+        return;
+    case 0xff:
+        qemu_system_shutdown_request(SHUTDOWN_CAUSE_GUEST_SHUTDOWN);
+        return;
+    default:
+        return;
+    }
+}
+
+static const MemoryRegionOps loongson3_pm_ops = {
+    .read  = loongson3_pm_read,
+    .write = loongson3_pm_write,
+    .endianness = DEVICE_NATIVE_ENDIAN,
+};
+
+#define DEF_TCG_FREQ (200 * 1000 * 1000)
+#define DEF_KVM_FREQ (1600 * 1000 * 1000)
+
+static uint64_t get_cpu_freq(void)
+{
+#ifdef CONFIG_KVM
+    int ret;
+    uint64_t freq;
+    struct kvm_one_reg freq_reg = {
+        .id = KVM_REG_MIPS_COUNT_HZ,
+        .addr = (uintptr_t)(&freq)
+    };
+
+    if (kvm_enabled()) {
+        ret = kvm_vcpu_ioctl(first_cpu, KVM_GET_ONE_REG, &freq_reg);
+        if (ret < 0) {
+            return DEF_KVM_FREQ;
+        }
+        return freq * 2;
+    } else {
+        /*
+         * TCG has a default CP0 Timer period 10 ns, which is 100MHz,
+         * CPU frequency is defined as double of CP0 timer frequency.
+         */
+        return DEF_TCG_FREQ;
+    }
+#else
+    return DEF_TCG_FREQ;
+#endif
+}
+
+static void init_boot_param(void)
+{
+    void *p;
+    struct boot_params *bp;
+
+    p = g_malloc0(loader_rommap[LOADER_PARAM].size);
+    bp = p;
+
+    stw_le_p(&bp->efi.smbios.vers, 1);
+    init_reset_system(&(bp->reset_system));
+    p += ROUND_UP(sizeof(struct boot_params), 64);
+    init_loongson_params(&(bp->efi.smbios.lp), p,
+                         loaderparams.cpu_freq, loaderparams.ram_size);
+
+    rom_add_blob_fixed("params_rom", bp,
+                       loader_rommap[LOADER_PARAM].size,
+                       loader_rommap[LOADER_PARAM].base);
+
+    g_free(bp);
+
+    loaderparams.a2 = cpu_mips_phys_to_kseg0(NULL, loader_rommap[LOADER_PARAM].base);
+}
+
+static void init_boot_rom(void)
+{
+    const unsigned int boot_code[] = {
+        0x40086000,   /* mfc0    t0, CP0_STATUS                               */
+        0x240900E4,   /* li      t1, 0xe4         #set kx, sx, ux, erl        */
+        0x01094025,   /* or      t0, t0, t1                                   */
+        0x3C090040,   /* lui     t1, 0x40         #set bev                    */
+        0x01094025,   /* or      t0, t0, t1                                   */
+        0x40886000,   /* mtc0    t0, CP0_STATUS                               */
+        0x00000000,
+        0x40806800,   /* mtc0    zero, CP0_CAUSE                              */
+        0x00000000,
+        0x400A7801,   /* mfc0    t2, $15, 1                                   */
+        0x314A00FF,   /* andi    t2, 0x0ff                                    */
+        0x3C089000,   /* dli     t0, 0x900000003ff01000                       */
+        0x00084438,
+        0x35083FF0,
+        0x00084438,
+        0x35081000,
+        0x314B0003,   /* andi    t3, t2, 0x3      #local cpuid                */
+        0x000B5A00,   /* sll     t3, 8                                        */
+        0x010B4025,   /* or      t0, t0, t3                                   */
+        0x314C000C,   /* andi    t4, t2, 0xc      #node id                    */
+        0x000C62BC,   /* dsll    t4, 42                                       */
+        0x010C4025,   /* or      t0, t0, t4                                   */
+                      /* WaitForInit:                                         */
+        0xDD020020,   /* ld      v0, FN_OFF(t0)   #FN_OFF 0x020               */
+        0x1040FFFE,   /* beqz    v0, WaitForInit                              */
+        0x00000000,   /* nop                                                  */
+        0xDD1D0028,   /* ld      sp, SP_OFF(t0)   #FN_OFF 0x028               */
+        0xDD1C0030,   /* ld      gp, GP_OFF(t0)   #FN_OFF 0x030               */
+        0xDD050038,   /* ld      a1, A1_OFF(t0)   #FN_OFF 0x038               */
+        0x00400008,   /* jr      v0               #byebye                     */
+        0x00000000,   /* nop                                                  */
+        0x1000FFFF,   /* 1:  b   1b                                           */
+        0x00000000,   /* nop                                                  */
+
+                      /* Reset                                                */
+        0x3C0C9000,   /* dli     t0, 0x9000000010080010                       */
+        0x358C0000,
+        0x000C6438,
+        0x358C1008,
+        0x000C6438,
+        0x358C0010,
+        0x240D0000,   /* li      t1, 0x00                                     */
+        0xA18D0000,   /* sb      t1, (t0)                                     */
+        0x1000FFFF,   /* 1:  b   1b                                           */
+        0x00000000,   /* nop                                                  */
+
+                      /* Shutdown                                             */
+        0x3C0C9000,   /* dli     t0, 0x9000000010080010                       */
+        0x358C0000,
+        0x000C6438,
+        0x358C1008,
+        0x000C6438,
+        0x358C0010,
+        0x240D00FF,   /* li      t1, 0xff                                     */
+        0xA18D0000,   /* sb      t1, (t0)                                     */
+        0x1000FFFF,   /* 1:  b   1b                                           */
+        0x00000000    /* nop                                                  */
+    };
+
+    rom_add_blob_fixed("boot_rom", boot_code, sizeof(boot_code),
+                        loader_rommap[LOADER_BOOTROM].base);
+}
+
+static void fw_cfg_boot_set(void *opaque, const char *boot_device,
+                            Error **errp)
+{
+    fw_cfg_modify_i16(opaque, FW_CFG_BOOT_DEVICE, boot_device[0]);
+}
+
+static void fw_conf_init(unsigned long ram_size)
+{
+    FWCfgState *fw_cfg;
+    hwaddr cfg_addr = virt_memmap[VIRT_FW_CFG].base;
+
+    fw_cfg = fw_cfg_init_mem_wide(cfg_addr, cfg_addr + 8, 8, 0, NULL);
+    fw_cfg_add_i16(fw_cfg, FW_CFG_NB_CPUS, (uint16_t)current_machine->smp.cpus);
+    fw_cfg_add_i16(fw_cfg, FW_CFG_MAX_CPUS, (uint16_t)current_machine->smp.max_cpus);
+    fw_cfg_add_i64(fw_cfg, FW_CFG_RAM_SIZE, (uint64_t)ram_size);
+    fw_cfg_add_i32(fw_cfg, FW_CFG_MACHINE_VERSION, 1);
+    fw_cfg_add_i64(fw_cfg, FW_CFG_CPU_FREQ, get_cpu_freq());
+    qemu_register_boot_set(fw_cfg_boot_set, fw_cfg);
+}
+
+static int set_prom_cmdline(ram_addr_t initrd_offset, long initrd_size)
+{
+    hwaddr cmdline_vaddr;
+    char memenv[32];
+    char highmemenv[32];
+    void *cmdline_buf;
+    unsigned int *parg_env;
+    int ret = 0;
+
+    /* Allocate cmdline_buf for command line. */
+    cmdline_buf = g_malloc0(loader_memmap[LOADER_CMDLINE].size);
+    cmdline_vaddr = cpu_mips_phys_to_kseg0(NULL,
+                                           loader_memmap[LOADER_CMDLINE].base);
+
+    /*
+     * Layout of cmdline_buf looks like this:
+     * argv[0], argv[1], 0, env[0], env[1], ... env[i], 0,
+     * argv[0]'s data, argv[1]'s data, env[0]'data, ..., env[i]'s data, 0
+     */
+    parg_env = (void *)cmdline_buf;
+
+    ret = (3 + 1) * 4;
+    *parg_env++ = cmdline_vaddr + ret;
+    ret += (1 + snprintf(cmdline_buf + ret, 256 - ret, "g"));
+
+    /* argv1 */
+    *parg_env++ = cmdline_vaddr + ret;
+    if (initrd_size > 0)
+        ret += (1 + snprintf(cmdline_buf + ret, 256 - ret,
+                "rd_start=0x" TARGET_FMT_lx " rd_size=%li %s",
+                cpu_mips_phys_to_kseg0(NULL, initrd_offset),
+                initrd_size, loaderparams.kernel_cmdline));
+    else
+        ret += (1 + snprintf(cmdline_buf + ret, 256 - ret, "%s",
+                loaderparams.kernel_cmdline));
+
+    /* argv2 */
+    *parg_env++ = cmdline_vaddr + 4 * ret;
+
+    /* env */
+    sprintf(memenv, "%d", 256);
+    sprintf(highmemenv, "%ld", (unsigned long)(loaderparams.ram_size / MiB) - 256);
+
+    rom_add_blob_fixed("cmdline", cmdline_buf,
+                       loader_memmap[LOADER_CMDLINE].size,
+                       loader_memmap[LOADER_CMDLINE].base);
+
+    g_free(cmdline_buf);
+
+    loaderparams.a0 = 2;
+    loaderparams.a1 = cmdline_vaddr;
+
+    return 0;
+}
+
+static uint64_t load_kernel(CPUMIPSState *env)
+{
+    long kernel_size;
+    ram_addr_t initrd_offset;
+    uint64_t kernel_entry, kernel_low, kernel_high, initrd_size;
+
+    kernel_size = load_elf(loaderparams.kernel_filename, NULL,
+                           cpu_mips_kseg0_to_phys, NULL,
+                           (uint64_t *)&kernel_entry,
+                           (uint64_t *)&kernel_low, (uint64_t *)&kernel_high,
+                           NULL, 0, EM_MIPS, 1, 0);
+    if (kernel_size < 0) {
+        error_report("could not load kernel '%s': %s",
+                     loaderparams.kernel_filename,
+                     load_elf_strerror(kernel_size));
+        exit(1);
+    }
+
+    /* load initrd */
+    initrd_size = 0;
+    initrd_offset = 0;
+    if (loaderparams.initrd_filename) {
+        initrd_size = get_image_size(loaderparams.initrd_filename);
+        if (initrd_size > 0) {
+            initrd_offset = (kernel_high + ~INITRD_PAGE_MASK) &
+                            INITRD_PAGE_MASK;
+            initrd_offset = MAX(initrd_offset,
+                                loader_memmap[LOADER_INITRD].base);
+
+            if (initrd_offset + initrd_size > ram_size) {
+                error_report("memory too small for initial ram disk '%s'",
+                             loaderparams.initrd_filename);
+                exit(1);
+            }
+
+            initrd_size = load_image_targphys(loaderparams.initrd_filename,
+                                              initrd_offset,
+                                              ram_size - initrd_offset);
+        }
+
+        if (initrd_size == (target_ulong) -1) {
+            error_report("could not load initial ram disk '%s'",
+                         loaderparams.initrd_filename);
+            exit(1);
+        }
+    }
+
+    /* Setup prom cmdline. */
+    set_prom_cmdline(initrd_offset, initrd_size);
+
+    return kernel_entry;
+}
+
+static void main_cpu_reset(void *opaque)
+{
+    MIPSCPU *cpu = opaque;
+    CPUMIPSState *env = &cpu->env;
+
+    cpu_reset(CPU(cpu));
+
+    /* Loongson-3 reset stuff */
+    if (loaderparams.kernel_filename) {
+        if (cpu == MIPS_CPU(first_cpu)) {
+            env->active_tc.gpr[4] = loaderparams.a0;
+            env->active_tc.gpr[5] = loaderparams.a1;
+            env->active_tc.gpr[6] = loaderparams.a2;
+            env->active_tc.PC = loaderparams.kernel_entry;
+        }
+        env->CP0_Status &= ~((1 << CP0St_BEV) | (1 << CP0St_ERL));
+    }
+}
+
+static inline void loongson3_virt_devices_init(MachineState *machine, DeviceState *pic)
+{
+    int i;
+    qemu_irq irq;
+    PCIBus *pci_bus;
+    DeviceState *dev;
+    MemoryRegion *pio_alias;
+    MemoryRegion *mmio_alias, *mmio_reg;
+    MemoryRegion *ecam_alias, *ecam_reg;
+
+    dev = qdev_new(TYPE_GPEX_HOST);
+    sysbus_realize_and_unref(SYS_BUS_DEVICE(dev), &error_fatal);
+    pci_bus = PCI_HOST_BRIDGE(dev)->bus;
+
+    ecam_alias = g_new0(MemoryRegion, 1);
+    ecam_reg = sysbus_mmio_get_region(SYS_BUS_DEVICE(dev), 0);
+    memory_region_init_alias(ecam_alias, OBJECT(dev), "pcie-ecam",
+                             ecam_reg, 0, virt_memmap[VIRT_PCIE_ECAM].size);
+    memory_region_add_subregion(get_system_memory(),
+                                virt_memmap[VIRT_PCIE_ECAM].base, ecam_alias);
+
+    mmio_alias = g_new0(MemoryRegion, 1);
+    mmio_reg = sysbus_mmio_get_region(SYS_BUS_DEVICE(dev), 1);
+    memory_region_init_alias(mmio_alias, OBJECT(dev), "pcie-mmio",
+                             mmio_reg, virt_memmap[VIRT_PCIE_MMIO].base,
+                             virt_memmap[VIRT_PCIE_MMIO].size);
+    memory_region_add_subregion(get_system_memory(),
+                                virt_memmap[VIRT_PCIE_MMIO].base, mmio_alias);
+
+    pio_alias = g_new0(MemoryRegion, 1);
+    memory_region_init_alias(pio_alias, OBJECT(dev), "pcie-pio",
+                             get_system_io(), 0, virt_memmap[VIRT_PCIE_PIO].size);
+    memory_region_add_subregion(get_system_memory(),
+                                virt_memmap[VIRT_PCIE_PIO].base, pio_alias);
+    sysbus_mmio_map(SYS_BUS_DEVICE(dev), 2, virt_memmap[VIRT_PCIE_PIO].base);
+
+    for (i = 0; i < GPEX_NUM_IRQS; i++) {
+        irq = qdev_get_gpio_in(pic, PCIE_IRQ_BASE + i);
+        sysbus_connect_irq(SYS_BUS_DEVICE(dev), i, irq);
+        gpex_set_irq_num(GPEX_HOST(dev), i, PCIE_IRQ_BASE + i);
+    }
+
+    pci_vga_init(pci_bus);
+
+    if (defaults_enabled()) {
+        pci_create_simple(pci_bus, -1, "pci-ohci");
+        usb_create_simple(usb_bus_find(-1), "usb-kbd");
+        usb_create_simple(usb_bus_find(-1), "usb-tablet");
+    }
+
+    for (i = 0; i < nb_nics; i++) {
+        NICInfo *nd = &nd_table[i];
+
+        if (!nd->model) {
+            nd->model = g_strdup("virtio");
+        }
+
+        pci_nic_init_nofail(nd, pci_bus, nd->model, NULL);
+    }
+}
+
+static void mips_loongson3_virt_init(MachineState *machine)
+{
+    int i;
+    long bios_size;
+    MIPSCPU *cpu;
+    CPUMIPSState *env;
+    DeviceState *liointc;
+    char *filename;
+    const char *kernel_cmdline = machine->kernel_cmdline;
+    const char *kernel_filename = machine->kernel_filename;
+    const char *initrd_filename = machine->initrd_filename;
+    ram_addr_t ram_size = machine->ram_size;
+    MemoryRegion *address_space_mem = get_system_memory();
+    MemoryRegion *ram = g_new(MemoryRegion, 1);
+    MemoryRegion *bios = g_new(MemoryRegion, 1);
+    MemoryRegion *iomem = g_new(MemoryRegion, 1);
+
+    /* TODO: TCG will support all CPU types */
+    if (!kvm_enabled()) {
+        if (!machine->cpu_type) {
+            machine->cpu_type = MIPS_CPU_TYPE_NAME("Loongson-3A1000");
+        }
+        if (!strstr(machine->cpu_type, "Loongson-3A1000")) {
+            error_report("Loongson-3/TCG needs cpu type Loongson-3A1000");
+            exit(1);
+        }
+    } else {
+        if (!machine->cpu_type) {
+            machine->cpu_type = MIPS_CPU_TYPE_NAME("Loongson-3A4000");
+        }
+        if (!strstr(machine->cpu_type, "Loongson-3A4000")) {
+            error_report("Loongson-3/KVM needs cpu type Loongson-3A4000");
+            exit(1);
+        }
+    }
+
+    if (ram_size < 512 * MiB) {
+        error_report("Loongson-3 machine needs at least 512MB memory");
+        exit(1);
+    }
+
+    /*
+     * The whole MMIO range among configure registers doesn't generate
+     * exception when accessing invalid memory. Create an unimplememted
+     * device to emulate this feature.
+     */
+    create_unimplemented_device("fallback", 0x10000000, 0x30000000);
+
+    liointc = qdev_new("loongson.liointc");
+    sysbus_realize_and_unref(SYS_BUS_DEVICE(liointc), &error_fatal);
+
+    sysbus_mmio_map(SYS_BUS_DEVICE(liointc), 0, virt_memmap[VIRT_LIOINTC].base);
+
+    for (i = 0; i < machine->smp.cpus; i++) {
+        int ip;
+
+        /* init CPUs */
+        cpu = MIPS_CPU(cpu_create(machine->cpu_type));
+
+        /* Init internal devices */
+        cpu_mips_irq_init_cpu(cpu);
+        cpu_mips_clock_init(cpu);
+        qemu_register_reset(main_cpu_reset, cpu);
+
+        if (i >= 4) {
+            continue; /* Only node-0 can be connected to LIOINTC */
+        }
+
+        for (ip = 0; ip < 4 ; ip++) {
+            int pin = i * 4 + ip;
+            sysbus_connect_irq(SYS_BUS_DEVICE(liointc),
+                               pin, cpu->env.irq[ip + 2]);
+        }
+    }
+    env = &MIPS_CPU(first_cpu)->env;
+
+    /* Allocate RAM/BIOS, 0x00000000~0x10000000 is alias of 0x80000000~0x90000000 */
+    memory_region_init_rom(bios, NULL, "loongson3.bios",
+                           virt_memmap[VIRT_BIOS_ROM].size, &error_fatal);
+    memory_region_init_alias(ram, NULL, "loongson3.lowmem",
+                           machine->ram, 0, virt_memmap[VIRT_LOWMEM].size);
+    memory_region_init_io(iomem, NULL, &loongson3_pm_ops,
+                           NULL, "loongson3_pm", virt_memmap[VIRT_PM].size);
+
+    memory_region_add_subregion(address_space_mem,
+                      virt_memmap[VIRT_LOWMEM].base, ram);
+    memory_region_add_subregion(address_space_mem,
+                      virt_memmap[VIRT_BIOS_ROM].base, bios);
+    memory_region_add_subregion(address_space_mem,
+                      virt_memmap[VIRT_HIGHMEM].base, machine->ram);
+    memory_region_add_subregion(address_space_mem,
+                      virt_memmap[VIRT_PM].base, iomem);
+
+    /*
+     * We do not support flash operation, just loading bios.bin as raw BIOS.
+     * Please use -L to set the BIOS path and -bios to set bios name.
+     */
+
+    if (kernel_filename) {
+        loaderparams.cpu_freq = get_cpu_freq();
+        loaderparams.ram_size = ram_size;
+        loaderparams.kernel_filename = kernel_filename;
+        loaderparams.kernel_cmdline = kernel_cmdline;
+        loaderparams.initrd_filename = initrd_filename;
+        loaderparams.kernel_entry = load_kernel(env);
+
+        init_boot_rom();
+        init_boot_param();
+    } else {
+        if (bios_name == NULL) {
+                bios_name = LOONGSON3_BIOSNAME;
+        }
+        filename = qemu_find_file(QEMU_FILE_TYPE_BIOS, bios_name);
+        if (filename) {
+            bios_size = load_image_targphys(filename,
+                                            virt_memmap[VIRT_BIOS_ROM].base,
+                                            virt_memmap[VIRT_BIOS_ROM].size);
+            g_free(filename);
+        } else {
+            bios_size = -1;
+        }
+
+        if ((bios_size < 0 || bios_size > virt_memmap[VIRT_BIOS_ROM].size) &&
+            !kernel_filename && !qtest_enabled()) {
+            error_report("Could not load MIPS bios '%s'", bios_name);
+            exit(1);
+        }
+
+        fw_conf_init(ram_size);
+    }
+
+    msi_nonbroken = true;
+    loongson3_virt_devices_init(machine, liointc);
+
+    sysbus_create_simple("goldfish_rtc", virt_memmap[VIRT_RTC].base,
+                         qdev_get_gpio_in(liointc, RTC_IRQ));
+
+    serial_mm_init(address_space_mem, virt_memmap[VIRT_UART].base, 0,
+                   qdev_get_gpio_in(liointc, UART_IRQ), 115200, serial_hd(0),
+                   DEVICE_NATIVE_ENDIAN);
+}
+
+static void mips_loongson3_virt_machine_init(MachineClass *mc)
+{
+    mc->desc = "Loongson-3 Virtualization Platform";
+    mc->init = mips_loongson3_virt_init;
+    mc->block_default_type = IF_IDE;
+    mc->max_cpus = LOONGSON_MAX_VCPUS;
+    mc->default_ram_id = "loongson3.highram";
+    mc->default_ram_size = 1600 * MiB;
+    mc->kvm_type = mips_kvm_type;
+    mc->minimum_page_bits = 14;
+}
+
+DEFINE_MACHINE("loongson3-virt", mips_loongson3_virt_machine_init)
diff --git a/hw/mips/meson.build b/hw/mips/meson.build
index c98391c..72db43c 100644
--- a/hw/mips/meson.build
+++ b/hw/mips/meson.build
@@ -1,6 +1,7 @@ 
 mips_ss = ss.source_set()
 mips_ss.add(files('addr.c', 'mips_int.c', 'fw_cfg.c'))
 mips_ss.add(when: 'CONFIG_FULOONG', if_true: files('fuloong2e.c'))
+mips_ss.add(when: 'CONFIG_LOONGSON3V', if_true: files('loongson3_bootp.c', 'loongson3_virt.c'))
 mips_ss.add(when: 'CONFIG_JAZZ', if_true: files('jazz.c'))
 mips_ss.add(when: 'CONFIG_MALTA', if_true: files('gt64xxx_pci.c', 'malta.c'))
 mips_ss.add(when: 'CONFIG_MIPSSIM', if_true: files('mipssim.c'))