| Message ID | 20200415195422.19866-6-atish.patra@wdc.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | Add UEFI support for RISC-V | expand |
Hi Atish,
Thank you for the patch! Perhaps something to improve:
[auto build test WARNING on efi/next]
[also build test WARNING on linus/master v5.7-rc1 next-20200415]
[cannot apply to arm/for-next arm64/for-next/core linux/master atish-riscv-linux/topo_v3]
[if your patch is applied to the wrong git tree, please drop us a note to help
improve the system. BTW, we also suggest to use '--base' option to specify the
base tree in git format-patch, please see https://stackoverflow.com/a/37406982]
url: https://github.com/0day-ci/linux/commits/Atish-Patra/Add-UEFI-support-for-RISC-V/20200416-065438
base: https://git.kernel.org/pub/scm/linux/kernel/git/efi/efi.git next
config: riscv-rv32_defconfig (attached as .config)
compiler: riscv32-linux-gcc (GCC) 9.3.0
reproduce:
wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
chmod +x ~/bin/make.cross
# save the attached .config to linux build tree
COMPILER_INSTALL_PATH=$HOME/0day GCC_VERSION=9.3.0 make.cross ARCH=riscv
If you fix the issue, kindly add following tag as appropriate
Reported-by: kbuild test robot <lkp@intel.com>
All warnings (new ones prefixed by >>):
In file included from include/linux/list.h:9,
from include/linux/preempt.h:11,
from include/linux/spinlock.h:51,
from include/linux/seqlock.h:36,
from include/linux/time.h:6,
from include/linux/efi.h:17,
from drivers/firmware/efi/libstub/riscv-stub.c:10:
drivers/firmware/efi/libstub/riscv-stub.c: In function 'handle_kernel_image':
>> drivers/firmware/efi/libstub/riscv-stub.c:89:17: warning: cast from pointer to integer of different size [-Wpointer-to-int-cast]
89 | if (IS_ALIGNED((u64)_start, MIN_KIMG_ALIGN)) {
| ^
include/linux/kernel.h:37:30: note: in definition of macro 'IS_ALIGNED'
37 | #define IS_ALIGNED(x, a) (((x) & ((typeof(x))(a) - 1)) == 0)
| ^
>> drivers/firmware/efi/libstub/riscv-stub.c:89:17: warning: cast from pointer to integer of different size [-Wpointer-to-int-cast]
89 | if (IS_ALIGNED((u64)_start, MIN_KIMG_ALIGN)) {
| ^
include/linux/kernel.h:37:44: note: in definition of macro 'IS_ALIGNED'
37 | #define IS_ALIGNED(x, a) (((x) & ((typeof(x))(a) - 1)) == 0)
| ^
drivers/firmware/efi/libstub/riscv-stub.c:94:17: warning: cast from pointer to integer of different size [-Wpointer-to-int-cast]
94 | *image_addr = (u64)_start;
| ^
vim +89 drivers/firmware/efi/libstub/riscv-stub.c
69
70 efi_status_t handle_kernel_image(unsigned long *image_addr,
71 unsigned long *image_size,
72 unsigned long *reserve_addr,
73 unsigned long *reserve_size,
74 unsigned long dram_base,
75 efi_loaded_image_t *image)
76 {
77 efi_status_t status;
78 unsigned long kernel_size, kernel_memsize = 0;
79 unsigned long max_alloc_address;
80
81 if (image->image_base != _start)
82 pr_efi_err("FIRMWARE BUG: efi_loaded_image_t::image_base has bogus value\n");
83
84 kernel_size = _edata - _start;
85 kernel_memsize = kernel_size + (_end - _edata);
86 max_alloc_address = round_up(dram_base, MIN_KIMG_ALIGN) +
87 kernel_memsize;
88
> 89 if (IS_ALIGNED((u64)_start, MIN_KIMG_ALIGN)) {
---
0-DAY CI Kernel Test Service, Intel Corporation
https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org
On Wed, 15 Apr 2020 at 21:54, Atish Patra <atish.patra@wdc.com> wrote: > > Add a RISC-V architecture specific stub code that actually copies the > actual kernel image to a valid address and jump to it after boot services > are terminated. Enable UEFI related kernel configs as well for RISC-V. > > Signed-off-by: Atish Patra <atish.patra@wdc.com> > --- > arch/riscv/Kconfig | 20 ++++ > arch/riscv/Makefile | 1 + > arch/riscv/configs/defconfig | 1 + > arch/riscv/include/asm/efi.h | 44 +++++++++ > drivers/firmware/efi/Kconfig | 2 +- > drivers/firmware/efi/libstub/Makefile | 7 ++ > drivers/firmware/efi/libstub/riscv-stub.c | 111 ++++++++++++++++++++++ > 7 files changed, 185 insertions(+), 1 deletion(-) > create mode 100644 arch/riscv/include/asm/efi.h > create mode 100644 drivers/firmware/efi/libstub/riscv-stub.c > > diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig > index f39e326a7a42..eb4f41c8f3ce 100644 > --- a/arch/riscv/Kconfig > +++ b/arch/riscv/Kconfig > @@ -379,10 +379,30 @@ config CMDLINE_FORCE > > endchoice > > +config EFI_STUB > + bool > + > +config EFI > + bool "UEFI runtime support" > + depends on OF > + select LIBFDT > + select UCS2_STRING > + select EFI_PARAMS_FROM_FDT > + select EFI_STUB > + select EFI_GENERIC_STUB > + default y > + help > + This option provides support for runtime services provided > + by UEFI firmware (such as non-volatile variables, realtime > + clock, and platform reset). A UEFI stub is also provided to > + allow the kernel to be booted as an EFI application. This > + is only useful on systems that have UEFI firmware. > + > endmenu > > menu "Power management options" > > source "kernel/power/Kconfig" > +source "drivers/firmware/Kconfig" > > endmenu > diff --git a/arch/riscv/Makefile b/arch/riscv/Makefile > index fb6e37db836d..079435804d6d 100644 > --- a/arch/riscv/Makefile > +++ b/arch/riscv/Makefile > @@ -80,6 +80,7 @@ head-y := arch/riscv/kernel/head.o > core-y += arch/riscv/ > > libs-y += arch/riscv/lib/ > +core-$(CONFIG_EFI_STUB) += $(objtree)/drivers/firmware/efi/libstub/lib.a > > PHONY += vdso_install > vdso_install: > diff --git a/arch/riscv/configs/defconfig b/arch/riscv/configs/defconfig > index 4da4886246a4..ae69e12d306a 100644 > --- a/arch/riscv/configs/defconfig > +++ b/arch/riscv/configs/defconfig > @@ -129,3 +129,4 @@ CONFIG_DEBUG_BLOCK_EXT_DEVT=y > # CONFIG_RUNTIME_TESTING_MENU is not set > CONFIG_MEMTEST=y > # CONFIG_SYSFS_SYSCALL is not set > +CONFIG_EFI=y > diff --git a/arch/riscv/include/asm/efi.h b/arch/riscv/include/asm/efi.h > new file mode 100644 > index 000000000000..62d7d5eafed8 > --- /dev/null > +++ b/arch/riscv/include/asm/efi.h > @@ -0,0 +1,44 @@ > +/* SPDX-License-Identifier: GPL-2.0 */ > +/* > + * Copyright (C) 2020 Western Digital Corporation or its affiliates. > + * Based on arch/arm64/include/asm/efi.h > + */ > +#ifndef _ASM_EFI_H > +#define _ASM_EFI_H > + > +#include <asm/io.h> > +#include <asm/mmu_context.h> > +#include <asm/ptrace.h> > +#include <asm/tlbflush.h> > + > +#define VA_BITS_MIN 39 > + > +/* on RISC-V, the FDT may be located anywhere in system RAM */ > +static inline unsigned long efi_get_max_fdt_addr(unsigned long dram_base) > +{ > + return ULONG_MAX; > +} > + > +/* Load initrd at enough distance from DRAM start */ > +static inline unsigned long efi_get_max_initrd_addr(unsigned long dram_base, > + unsigned long image_addr) > +{ > + return dram_base + SZ_256M; > +} > + > +#define efi_bs_call(func, ...) efi_system_table()->boottime->func(__VA_ARGS__) > +#define efi_rt_call(func, ...) efi_system_table()->runtime->func(__VA_ARGS__) > +#define efi_is_native() (true) > + > +#define efi_table_attr(inst, attr) (inst->attr) > + > +#define efi_call_proto(inst, func, ...) inst->func(inst, ##__VA_ARGS__) > + > +#define alloc_screen_info(x...) (&screen_info) > +extern char stext_offset[]; > + > +static inline void free_screen_info(struct screen_info *si) > +{ > +} > + > +#endif /* _ASM_EFI_H */ > diff --git a/drivers/firmware/efi/Kconfig b/drivers/firmware/efi/Kconfig > index 2a2b2b96a1dc..fcdc789d3f87 100644 > --- a/drivers/firmware/efi/Kconfig > +++ b/drivers/firmware/efi/Kconfig > @@ -111,7 +111,7 @@ config EFI_GENERIC_STUB > > config EFI_ARMSTUB_DTB_LOADER > bool "Enable the DTB loader" > - depends on EFI_GENERIC_STUB > + depends on EFI_GENERIC_STUB && !RISCV > default y > help > Select this config option to add support for the dtb= command > diff --git a/drivers/firmware/efi/libstub/Makefile b/drivers/firmware/efi/libstub/Makefile > index 2b4e09bf987c..7d46b70b51f2 100644 > --- a/drivers/firmware/efi/libstub/Makefile > +++ b/drivers/firmware/efi/libstub/Makefile > @@ -22,6 +22,8 @@ cflags-$(CONFIG_ARM64) := $(subst $(CC_FLAGS_FTRACE),,$(KBUILD_CFLAGS)) \ > cflags-$(CONFIG_ARM) := $(subst $(CC_FLAGS_FTRACE),,$(KBUILD_CFLAGS)) \ > -fno-builtin -fpic \ > $(call cc-option,-mno-single-pic-base) > +cflags-$(CONFIG_RISCV) := $(subst $(CC_FLAGS_FTRACE),,$(KBUILD_CFLAGS)) \ > + -fpic > > cflags-$(CONFIG_EFI_GENERIC_STUB) += -I$(srctree)/scripts/dtc/libfdt > > @@ -57,6 +59,7 @@ lib-$(CONFIG_EFI_GENERIC_STUB) += efi-stub.o fdt.o string.o \ > lib-$(CONFIG_ARM) += arm32-stub.o > lib-$(CONFIG_ARM64) += arm64-stub.o > lib-$(CONFIG_X86) += x86-stub.o > +lib-$(CONFIG_RISCV) += riscv-stub.o > CFLAGS_arm32-stub.o := -DTEXT_OFFSET=$(TEXT_OFFSET) > CFLAGS_arm64-stub.o := -DTEXT_OFFSET=$(TEXT_OFFSET) > > @@ -81,6 +84,10 @@ STUBCOPY_FLAGS-$(CONFIG_ARM64) += --prefix-alloc-sections=.init \ > --prefix-symbols=__efistub_ > STUBCOPY_RELOC-$(CONFIG_ARM64) := R_AARCH64_ABS > > +STUBCOPY_FLAGS-$(CONFIG_RISCV) += --prefix-alloc-sections=.init \ > + --prefix-symbols=__efistub_ > +STUBCOPY_RELOC-$(CONFIG_RISCV) := R_RISCV_HI20 > + > $(obj)/%.stub.o: $(obj)/%.o FORCE > $(call if_changed,stubcopy) > > diff --git a/drivers/firmware/efi/libstub/riscv-stub.c b/drivers/firmware/efi/libstub/riscv-stub.c > new file mode 100644 > index 000000000000..69d13e0ebaea > --- /dev/null > +++ b/drivers/firmware/efi/libstub/riscv-stub.c > @@ -0,0 +1,111 @@ > +// SPDX-License-Identifier: GPL-2.0 > +/* > + * Copyright (C) 2013, 2014 Linaro Ltd; <roy.franz@linaro.org> > + * Copyright (C) 2020 Western Digital Corporation or its affiliates. > + * > + * This file implements the EFI boot stub for the RISC-V kernel. > + * Adapted from ARM64 version at drivers/firmware/efi/libstub/arm64-stub.c. > + */ > + > +#include <linux/efi.h> > +#include <linux/libfdt.h> > +#include <linux/libfdt_env.h> > +#include <asm/efi.h> > +#include <asm/sections.h> > + > +#include "efistub.h" > +/* > + * RISCV requires the kernel image to placed TEXT_OFFSET bytes beyond a 2 MB > + * aligned base for 64 bit and 4MB for 32 bit. > + */ > +#ifdef CONFIG_64BIT > +#define MIN_KIMG_ALIGN SZ_2M > +#else > +#define MIN_KIMG_ALIGN SZ_4M > +#endif > + > +typedef __attribute__((noreturn)) void (*jump_kernel_func)(unsigned int, > + unsigned long); > +efi_status_t check_platform_features(void) > +{ > + return EFI_SUCCESS; > +} > + > +static u32 get_boot_hartid_from_fdt(unsigned long fdt) > +{ > + int chosen_node, len; > + const fdt32_t *prop; > + > + chosen_node = fdt_path_offset((void *)fdt, "/chosen"); > + if (chosen_node < 0) > + return U32_MAX; > + prop = fdt_getprop((void *)fdt, chosen_node, "boot-hartid", &len); > + if (!prop || len != sizeof(u32)) > + return U32_MAX; > + > + return fdt32_to_cpu(*prop); > +} > + > +/* > + * Jump to real kernel here with following constraints. > + * 1. MMU should be disabled. > + * 2. a0 should contain hartid > + * 3. a1 should DT address > + */ > +void __noreturn efi_enter_kernel(unsigned long entrypoint, unsigned long fdt, > + unsigned long fdt_size) > +{ > + unsigned long kernel_entry = entrypoint + (unsigned long)stext_offset; > + jump_kernel_func jump_kernel = (jump_kernel_func) kernel_entry; > + u32 hartid = get_boot_hartid_from_fdt(fdt); > + > + if (hartid == U32_MAX) > + /* We can not use panic or BUG at this point */ > + __asm__ __volatile__ ("ebreak"); > + /* Disable MMU */ > + csr_write(CSR_SATP, 0); > + jump_kernel(hartid, fdt); > +} > + > +efi_status_t handle_kernel_image(unsigned long *image_addr, > + unsigned long *image_size, > + unsigned long *reserve_addr, > + unsigned long *reserve_size, > + unsigned long dram_base, > + efi_loaded_image_t *image) > +{ > + efi_status_t status; > + unsigned long kernel_size, kernel_memsize = 0; > + unsigned long max_alloc_address; > + > + if (image->image_base != _start) > + pr_efi_err("FIRMWARE BUG: efi_loaded_image_t::image_base has bogus value\n"); > + I don't think you need this. > + kernel_size = _edata - _start; > + kernel_memsize = kernel_size + (_end - _edata); > + max_alloc_address = round_up(dram_base, MIN_KIMG_ALIGN) + > + kernel_memsize; > + You said the kernel could be anywhere in memory, as long as it is aligned correctly, right? In that case, you don't need this, you can simply pass ULONG_MAX as the max address. > + if (IS_ALIGNED((u64)_start, MIN_KIMG_ALIGN)) { > + /* > + * Just execute from wherever we were loaded by the > + * UEFI PE/COFF loader if the alignment is suitable. > + */ > + *image_addr = (u64)_start; Change these casts to (unsigned long), as reported by the robot. So you no longer need the placement to be TEXT_OFFSET bytes past a MIN_KIMG_ALIGN aligned boundary, right? > + *reserve_size = 0; > + return EFI_SUCCESS; > + } > + status = efi_allocate_pages_aligned(*reserve_size, reserve_addr, > + max_alloc_address, MIN_KIMG_ALIGN); > + > + if (status != EFI_SUCCESS) { > + pr_efi_err("Failed to relocate kernel\n"); > + *reserve_size = 0; > + return status; > + } > + *image_addr = *reserve_addr; > + > + memcpy((void *)*image_addr, _start, kernel_size); > + > + return EFI_SUCCESS; > +} > -- > 2.24.0 >
On Thu, Apr 16, 2020 at 12:41 AM Ard Biesheuvel <ardb@kernel.org> wrote: > > On Wed, 15 Apr 2020 at 21:54, Atish Patra <atish.patra@wdc.com> wrote: > > > > Add a RISC-V architecture specific stub code that actually copies the > > actual kernel image to a valid address and jump to it after boot services > > are terminated. Enable UEFI related kernel configs as well for RISC-V. > > > > Signed-off-by: Atish Patra <atish.patra@wdc.com> > > --- > > arch/riscv/Kconfig | 20 ++++ > > arch/riscv/Makefile | 1 + > > arch/riscv/configs/defconfig | 1 + > > arch/riscv/include/asm/efi.h | 44 +++++++++ > > drivers/firmware/efi/Kconfig | 2 +- > > drivers/firmware/efi/libstub/Makefile | 7 ++ > > drivers/firmware/efi/libstub/riscv-stub.c | 111 ++++++++++++++++++++++ > > 7 files changed, 185 insertions(+), 1 deletion(-) > > create mode 100644 arch/riscv/include/asm/efi.h > > create mode 100644 drivers/firmware/efi/libstub/riscv-stub.c > > > > diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig > > index f39e326a7a42..eb4f41c8f3ce 100644 > > --- a/arch/riscv/Kconfig > > +++ b/arch/riscv/Kconfig > > @@ -379,10 +379,30 @@ config CMDLINE_FORCE > > > > endchoice > > > > +config EFI_STUB > > + bool > > + > > +config EFI > > + bool "UEFI runtime support" > > + depends on OF > > + select LIBFDT > > + select UCS2_STRING > > + select EFI_PARAMS_FROM_FDT > > + select EFI_STUB > > + select EFI_GENERIC_STUB > > + default y > > + help > > + This option provides support for runtime services provided > > + by UEFI firmware (such as non-volatile variables, realtime > > + clock, and platform reset). A UEFI stub is also provided to > > + allow the kernel to be booted as an EFI application. This > > + is only useful on systems that have UEFI firmware. > > + > > endmenu > > > > menu "Power management options" > > > > source "kernel/power/Kconfig" > > +source "drivers/firmware/Kconfig" > > > > endmenu > > diff --git a/arch/riscv/Makefile b/arch/riscv/Makefile > > index fb6e37db836d..079435804d6d 100644 > > --- a/arch/riscv/Makefile > > +++ b/arch/riscv/Makefile > > @@ -80,6 +80,7 @@ head-y := arch/riscv/kernel/head.o > > core-y += arch/riscv/ > > > > libs-y += arch/riscv/lib/ > > +core-$(CONFIG_EFI_STUB) += $(objtree)/drivers/firmware/efi/libstub/lib.a > > > > PHONY += vdso_install > > vdso_install: > > diff --git a/arch/riscv/configs/defconfig b/arch/riscv/configs/defconfig > > index 4da4886246a4..ae69e12d306a 100644 > > --- a/arch/riscv/configs/defconfig > > +++ b/arch/riscv/configs/defconfig > > @@ -129,3 +129,4 @@ CONFIG_DEBUG_BLOCK_EXT_DEVT=y > > # CONFIG_RUNTIME_TESTING_MENU is not set > > CONFIG_MEMTEST=y > > # CONFIG_SYSFS_SYSCALL is not set > > +CONFIG_EFI=y > > diff --git a/arch/riscv/include/asm/efi.h b/arch/riscv/include/asm/efi.h > > new file mode 100644 > > index 000000000000..62d7d5eafed8 > > --- /dev/null > > +++ b/arch/riscv/include/asm/efi.h > > @@ -0,0 +1,44 @@ > > +/* SPDX-License-Identifier: GPL-2.0 */ > > +/* > > + * Copyright (C) 2020 Western Digital Corporation or its affiliates. > > + * Based on arch/arm64/include/asm/efi.h > > + */ > > +#ifndef _ASM_EFI_H > > +#define _ASM_EFI_H > > + > > +#include <asm/io.h> > > +#include <asm/mmu_context.h> > > +#include <asm/ptrace.h> > > +#include <asm/tlbflush.h> > > + > > +#define VA_BITS_MIN 39 > > + > > +/* on RISC-V, the FDT may be located anywhere in system RAM */ > > +static inline unsigned long efi_get_max_fdt_addr(unsigned long dram_base) > > +{ > > + return ULONG_MAX; > > +} > > + > > +/* Load initrd at enough distance from DRAM start */ > > +static inline unsigned long efi_get_max_initrd_addr(unsigned long dram_base, > > + unsigned long image_addr) > > +{ > > + return dram_base + SZ_256M; > > +} > > + > > +#define efi_bs_call(func, ...) efi_system_table()->boottime->func(__VA_ARGS__) > > +#define efi_rt_call(func, ...) efi_system_table()->runtime->func(__VA_ARGS__) > > +#define efi_is_native() (true) > > + > > +#define efi_table_attr(inst, attr) (inst->attr) > > + > > +#define efi_call_proto(inst, func, ...) inst->func(inst, ##__VA_ARGS__) > > + > > +#define alloc_screen_info(x...) (&screen_info) > > +extern char stext_offset[]; > > + > > +static inline void free_screen_info(struct screen_info *si) > > +{ > > +} > > + > > +#endif /* _ASM_EFI_H */ > > diff --git a/drivers/firmware/efi/Kconfig b/drivers/firmware/efi/Kconfig > > index 2a2b2b96a1dc..fcdc789d3f87 100644 > > --- a/drivers/firmware/efi/Kconfig > > +++ b/drivers/firmware/efi/Kconfig > > @@ -111,7 +111,7 @@ config EFI_GENERIC_STUB > > > > config EFI_ARMSTUB_DTB_LOADER > > bool "Enable the DTB loader" > > - depends on EFI_GENERIC_STUB > > + depends on EFI_GENERIC_STUB && !RISCV > > default y > > help > > Select this config option to add support for the dtb= command > > diff --git a/drivers/firmware/efi/libstub/Makefile b/drivers/firmware/efi/libstub/Makefile > > index 2b4e09bf987c..7d46b70b51f2 100644 > > --- a/drivers/firmware/efi/libstub/Makefile > > +++ b/drivers/firmware/efi/libstub/Makefile > > @@ -22,6 +22,8 @@ cflags-$(CONFIG_ARM64) := $(subst $(CC_FLAGS_FTRACE),,$(KBUILD_CFLAGS)) \ > > cflags-$(CONFIG_ARM) := $(subst $(CC_FLAGS_FTRACE),,$(KBUILD_CFLAGS)) \ > > -fno-builtin -fpic \ > > $(call cc-option,-mno-single-pic-base) > > +cflags-$(CONFIG_RISCV) := $(subst $(CC_FLAGS_FTRACE),,$(KBUILD_CFLAGS)) \ > > + -fpic > > > > cflags-$(CONFIG_EFI_GENERIC_STUB) += -I$(srctree)/scripts/dtc/libfdt > > > > @@ -57,6 +59,7 @@ lib-$(CONFIG_EFI_GENERIC_STUB) += efi-stub.o fdt.o string.o \ > > lib-$(CONFIG_ARM) += arm32-stub.o > > lib-$(CONFIG_ARM64) += arm64-stub.o > > lib-$(CONFIG_X86) += x86-stub.o > > +lib-$(CONFIG_RISCV) += riscv-stub.o > > CFLAGS_arm32-stub.o := -DTEXT_OFFSET=$(TEXT_OFFSET) > > CFLAGS_arm64-stub.o := -DTEXT_OFFSET=$(TEXT_OFFSET) > > > > @@ -81,6 +84,10 @@ STUBCOPY_FLAGS-$(CONFIG_ARM64) += --prefix-alloc-sections=.init \ > > --prefix-symbols=__efistub_ > > STUBCOPY_RELOC-$(CONFIG_ARM64) := R_AARCH64_ABS > > > > +STUBCOPY_FLAGS-$(CONFIG_RISCV) += --prefix-alloc-sections=.init \ > > + --prefix-symbols=__efistub_ > > +STUBCOPY_RELOC-$(CONFIG_RISCV) := R_RISCV_HI20 > > + > > $(obj)/%.stub.o: $(obj)/%.o FORCE > > $(call if_changed,stubcopy) > > > > diff --git a/drivers/firmware/efi/libstub/riscv-stub.c b/drivers/firmware/efi/libstub/riscv-stub.c > > new file mode 100644 > > index 000000000000..69d13e0ebaea > > --- /dev/null > > +++ b/drivers/firmware/efi/libstub/riscv-stub.c > > @@ -0,0 +1,111 @@ > > +// SPDX-License-Identifier: GPL-2.0 > > +/* > > + * Copyright (C) 2013, 2014 Linaro Ltd; <roy.franz@linaro.org> > > + * Copyright (C) 2020 Western Digital Corporation or its affiliates. > > + * > > + * This file implements the EFI boot stub for the RISC-V kernel. > > + * Adapted from ARM64 version at drivers/firmware/efi/libstub/arm64-stub.c. > > + */ > > + > > +#include <linux/efi.h> > > +#include <linux/libfdt.h> > > +#include <linux/libfdt_env.h> > > +#include <asm/efi.h> > > +#include <asm/sections.h> > > + > > +#include "efistub.h" > > +/* > > + * RISCV requires the kernel image to placed TEXT_OFFSET bytes beyond a 2 MB > > + * aligned base for 64 bit and 4MB for 32 bit. > > + */ Fixed the comment. > > +#ifdef CONFIG_64BIT > > +#define MIN_KIMG_ALIGN SZ_2M > > +#else > > +#define MIN_KIMG_ALIGN SZ_4M > > +#endif > > + > > +typedef __attribute__((noreturn)) void (*jump_kernel_func)(unsigned int, > > + unsigned long); > > +efi_status_t check_platform_features(void) > > +{ > > + return EFI_SUCCESS; > > +} > > + > > +static u32 get_boot_hartid_from_fdt(unsigned long fdt) > > +{ > > + int chosen_node, len; > > + const fdt32_t *prop; > > + > > + chosen_node = fdt_path_offset((void *)fdt, "/chosen"); > > + if (chosen_node < 0) > > + return U32_MAX; > > + prop = fdt_getprop((void *)fdt, chosen_node, "boot-hartid", &len); > > + if (!prop || len != sizeof(u32)) > > + return U32_MAX; > > + > > + return fdt32_to_cpu(*prop); > > +} > > + > > +/* > > + * Jump to real kernel here with following constraints. > > + * 1. MMU should be disabled. > > + * 2. a0 should contain hartid > > + * 3. a1 should DT address > > + */ > > +void __noreturn efi_enter_kernel(unsigned long entrypoint, unsigned long fdt, > > + unsigned long fdt_size) > > +{ > > + unsigned long kernel_entry = entrypoint + (unsigned long)stext_offset; > > + jump_kernel_func jump_kernel = (jump_kernel_func) kernel_entry; > > + u32 hartid = get_boot_hartid_from_fdt(fdt); > > + > > + if (hartid == U32_MAX) > > + /* We can not use panic or BUG at this point */ > > + __asm__ __volatile__ ("ebreak"); > > + /* Disable MMU */ > > + csr_write(CSR_SATP, 0); > > + jump_kernel(hartid, fdt); > > +} > > + > > +efi_status_t handle_kernel_image(unsigned long *image_addr, > > + unsigned long *image_size, > > + unsigned long *reserve_addr, > > + unsigned long *reserve_size, > > + unsigned long dram_base, > > + efi_loaded_image_t *image) > > +{ > > + efi_status_t status; > > + unsigned long kernel_size, kernel_memsize = 0; > > + unsigned long max_alloc_address; > > + > > + if (image->image_base != _start) > > + pr_efi_err("FIRMWARE BUG: efi_loaded_image_t::image_base has bogus value\n"); > > + > > I don't think you need this. > Sure. I will remove it. I guess ARM64 code has the error print for legacy loader code ? > > + kernel_size = _edata - _start; > > + kernel_memsize = kernel_size + (_end - _edata); > > + max_alloc_address = round_up(dram_base, MIN_KIMG_ALIGN) + > > + kernel_memsize; > > + > > You said the kernel could be anywhere in memory, as long as it is > aligned correctly, right? Sorry I was wrong about this. RISC-V kernel maps PAGE_OFFSET virtual address to the physical address <xyz> where it is booted. That means memory between dram start and and <xyz> address will be unusable. I also realized that the above computing max_address as above also won't work for the following reason. efi_allocate_pages_aligned actually ALIGN_DOWN the max_address. Thus, efi won't find enough free memory in this case if the max_address is computed from the dram_base. Is there an implicit requirement for efi_allocate_pages_aligned or efi_low_alloc_above should be tried in case of failure? > In that case, you don't need this, you can simply pass ULONG_MAX as > the max address. > As RISC-V should allocate memory as low as possible to avoid memory wastage, I think the following should work. efi_low_alloc_above(*reserve_size, MIN_KIMG_ALIGN, reserve_addr, dram_base); If this looks okay to you, efi_low_alloc_above should be moved back to mem.c from relocate.c. Should I do it in a separate patch or the original patch should be modified so that efi_low_alloc_above was never moved to relocate.c > > + if (IS_ALIGNED((u64)_start, MIN_KIMG_ALIGN)) { > > + /* > > + * Just execute from wherever we were loaded by the > > + * UEFI PE/COFF loader if the alignment is suitable. > > + */ > > + *image_addr = (u64)_start; > > Change these casts to (unsigned long), as reported by the robot. > Done. > So you no longer need the placement to be TEXT_OFFSET bytes past a > MIN_KIMG_ALIGN aligned boundary, right? > Nope. EFI memory marked the firmware area as reserved. So EFI memory allocator will make sure that it never allocates memory from that region. > > + *reserve_size = 0; > > + return EFI_SUCCESS; > > + } > > + status = efi_allocate_pages_aligned(*reserve_size, reserve_addr, > > + max_alloc_address, MIN_KIMG_ALIGN); > > + > > + if (status != EFI_SUCCESS) { > > + pr_efi_err("Failed to relocate kernel\n"); > > + *reserve_size = 0; > > + return status; > > + } > > + *image_addr = *reserve_addr; > > + > > + memcpy((void *)*image_addr, _start, kernel_size); > > + > > + return EFI_SUCCESS; > > +} > > -- > > 2.24.0 > > > > _______________________________________________ > linux-arm-kernel mailing list > linux-arm-kernel@lists.infradead.org > http://lists.infradead.org/mailman/listinfo/linux-arm-kernel -- Regards, Atish
On Sat, 18 Apr 2020 at 05:03, Atish Patra <atishp@atishpatra.org> wrote: > > On Thu, Apr 16, 2020 at 12:41 AM Ard Biesheuvel <ardb@kernel.org> wrote: > > > > On Wed, 15 Apr 2020 at 21:54, Atish Patra <atish.patra@wdc.com> wrote: > > > > > > Add a RISC-V architecture specific stub code that actually copies the > > > actual kernel image to a valid address and jump to it after boot services > > > are terminated. Enable UEFI related kernel configs as well for RISC-V. > > > > > > Signed-off-by: Atish Patra <atish.patra@wdc.com> > > > --- > > > arch/riscv/Kconfig | 20 ++++ > > > arch/riscv/Makefile | 1 + > > > arch/riscv/configs/defconfig | 1 + > > > arch/riscv/include/asm/efi.h | 44 +++++++++ > > > drivers/firmware/efi/Kconfig | 2 +- > > > drivers/firmware/efi/libstub/Makefile | 7 ++ > > > drivers/firmware/efi/libstub/riscv-stub.c | 111 ++++++++++++++++++++++ > > > 7 files changed, 185 insertions(+), 1 deletion(-) > > > create mode 100644 arch/riscv/include/asm/efi.h > > > create mode 100644 drivers/firmware/efi/libstub/riscv-stub.c > > > > > > diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig > > > index f39e326a7a42..eb4f41c8f3ce 100644 > > > --- a/arch/riscv/Kconfig > > > +++ b/arch/riscv/Kconfig > > > @@ -379,10 +379,30 @@ config CMDLINE_FORCE > > > > > > endchoice > > > > > > +config EFI_STUB > > > + bool > > > + > > > +config EFI > > > + bool "UEFI runtime support" > > > + depends on OF > > > + select LIBFDT > > > + select UCS2_STRING > > > + select EFI_PARAMS_FROM_FDT > > > + select EFI_STUB > > > + select EFI_GENERIC_STUB > > > + default y > > > + help > > > + This option provides support for runtime services provided > > > + by UEFI firmware (such as non-volatile variables, realtime > > > + clock, and platform reset). A UEFI stub is also provided to > > > + allow the kernel to be booted as an EFI application. This > > > + is only useful on systems that have UEFI firmware. > > > + > > > endmenu > > > > > > menu "Power management options" > > > > > > source "kernel/power/Kconfig" > > > +source "drivers/firmware/Kconfig" > > > > > > endmenu > > > diff --git a/arch/riscv/Makefile b/arch/riscv/Makefile > > > index fb6e37db836d..079435804d6d 100644 > > > --- a/arch/riscv/Makefile > > > +++ b/arch/riscv/Makefile > > > @@ -80,6 +80,7 @@ head-y := arch/riscv/kernel/head.o > > > core-y += arch/riscv/ > > > > > > libs-y += arch/riscv/lib/ > > > +core-$(CONFIG_EFI_STUB) += $(objtree)/drivers/firmware/efi/libstub/lib.a > > > > > > PHONY += vdso_install > > > vdso_install: > > > diff --git a/arch/riscv/configs/defconfig b/arch/riscv/configs/defconfig > > > index 4da4886246a4..ae69e12d306a 100644 > > > --- a/arch/riscv/configs/defconfig > > > +++ b/arch/riscv/configs/defconfig > > > @@ -129,3 +129,4 @@ CONFIG_DEBUG_BLOCK_EXT_DEVT=y > > > # CONFIG_RUNTIME_TESTING_MENU is not set > > > CONFIG_MEMTEST=y > > > # CONFIG_SYSFS_SYSCALL is not set > > > +CONFIG_EFI=y > > > diff --git a/arch/riscv/include/asm/efi.h b/arch/riscv/include/asm/efi.h > > > new file mode 100644 > > > index 000000000000..62d7d5eafed8 > > > --- /dev/null > > > +++ b/arch/riscv/include/asm/efi.h > > > @@ -0,0 +1,44 @@ > > > +/* SPDX-License-Identifier: GPL-2.0 */ > > > +/* > > > + * Copyright (C) 2020 Western Digital Corporation or its affiliates. > > > + * Based on arch/arm64/include/asm/efi.h > > > + */ > > > +#ifndef _ASM_EFI_H > > > +#define _ASM_EFI_H > > > + > > > +#include <asm/io.h> > > > +#include <asm/mmu_context.h> > > > +#include <asm/ptrace.h> > > > +#include <asm/tlbflush.h> > > > + > > > +#define VA_BITS_MIN 39 > > > + > > > +/* on RISC-V, the FDT may be located anywhere in system RAM */ > > > +static inline unsigned long efi_get_max_fdt_addr(unsigned long dram_base) > > > +{ > > > + return ULONG_MAX; > > > +} > > > + > > > +/* Load initrd at enough distance from DRAM start */ > > > +static inline unsigned long efi_get_max_initrd_addr(unsigned long dram_base, > > > + unsigned long image_addr) > > > +{ > > > + return dram_base + SZ_256M; > > > +} > > > + > > > +#define efi_bs_call(func, ...) efi_system_table()->boottime->func(__VA_ARGS__) > > > +#define efi_rt_call(func, ...) efi_system_table()->runtime->func(__VA_ARGS__) > > > +#define efi_is_native() (true) > > > + > > > +#define efi_table_attr(inst, attr) (inst->attr) > > > + > > > +#define efi_call_proto(inst, func, ...) inst->func(inst, ##__VA_ARGS__) > > > + > > > +#define alloc_screen_info(x...) (&screen_info) > > > +extern char stext_offset[]; > > > + > > > +static inline void free_screen_info(struct screen_info *si) > > > +{ > > > +} > > > + > > > +#endif /* _ASM_EFI_H */ > > > diff --git a/drivers/firmware/efi/Kconfig b/drivers/firmware/efi/Kconfig > > > index 2a2b2b96a1dc..fcdc789d3f87 100644 > > > --- a/drivers/firmware/efi/Kconfig > > > +++ b/drivers/firmware/efi/Kconfig > > > @@ -111,7 +111,7 @@ config EFI_GENERIC_STUB > > > > > > config EFI_ARMSTUB_DTB_LOADER > > > bool "Enable the DTB loader" > > > - depends on EFI_GENERIC_STUB > > > + depends on EFI_GENERIC_STUB && !RISCV > > > default y > > > help > > > Select this config option to add support for the dtb= command > > > diff --git a/drivers/firmware/efi/libstub/Makefile b/drivers/firmware/efi/libstub/Makefile > > > index 2b4e09bf987c..7d46b70b51f2 100644 > > > --- a/drivers/firmware/efi/libstub/Makefile > > > +++ b/drivers/firmware/efi/libstub/Makefile > > > @@ -22,6 +22,8 @@ cflags-$(CONFIG_ARM64) := $(subst $(CC_FLAGS_FTRACE),,$(KBUILD_CFLAGS)) \ > > > cflags-$(CONFIG_ARM) := $(subst $(CC_FLAGS_FTRACE),,$(KBUILD_CFLAGS)) \ > > > -fno-builtin -fpic \ > > > $(call cc-option,-mno-single-pic-base) > > > +cflags-$(CONFIG_RISCV) := $(subst $(CC_FLAGS_FTRACE),,$(KBUILD_CFLAGS)) \ > > > + -fpic > > > > > > cflags-$(CONFIG_EFI_GENERIC_STUB) += -I$(srctree)/scripts/dtc/libfdt > > > > > > @@ -57,6 +59,7 @@ lib-$(CONFIG_EFI_GENERIC_STUB) += efi-stub.o fdt.o string.o \ > > > lib-$(CONFIG_ARM) += arm32-stub.o > > > lib-$(CONFIG_ARM64) += arm64-stub.o > > > lib-$(CONFIG_X86) += x86-stub.o > > > +lib-$(CONFIG_RISCV) += riscv-stub.o > > > CFLAGS_arm32-stub.o := -DTEXT_OFFSET=$(TEXT_OFFSET) > > > CFLAGS_arm64-stub.o := -DTEXT_OFFSET=$(TEXT_OFFSET) > > > > > > @@ -81,6 +84,10 @@ STUBCOPY_FLAGS-$(CONFIG_ARM64) += --prefix-alloc-sections=.init \ > > > --prefix-symbols=__efistub_ > > > STUBCOPY_RELOC-$(CONFIG_ARM64) := R_AARCH64_ABS > > > > > > +STUBCOPY_FLAGS-$(CONFIG_RISCV) += --prefix-alloc-sections=.init \ > > > + --prefix-symbols=__efistub_ > > > +STUBCOPY_RELOC-$(CONFIG_RISCV) := R_RISCV_HI20 > > > + > > > $(obj)/%.stub.o: $(obj)/%.o FORCE > > > $(call if_changed,stubcopy) > > > > > > diff --git a/drivers/firmware/efi/libstub/riscv-stub.c b/drivers/firmware/efi/libstub/riscv-stub.c > > > new file mode 100644 > > > index 000000000000..69d13e0ebaea > > > --- /dev/null > > > +++ b/drivers/firmware/efi/libstub/riscv-stub.c > > > @@ -0,0 +1,111 @@ > > > +// SPDX-License-Identifier: GPL-2.0 > > > +/* > > > + * Copyright (C) 2013, 2014 Linaro Ltd; <roy.franz@linaro.org> > > > + * Copyright (C) 2020 Western Digital Corporation or its affiliates. > > > + * > > > + * This file implements the EFI boot stub for the RISC-V kernel. > > > + * Adapted from ARM64 version at drivers/firmware/efi/libstub/arm64-stub.c. > > > + */ > > > + > > > +#include <linux/efi.h> > > > +#include <linux/libfdt.h> > > > +#include <linux/libfdt_env.h> > > > +#include <asm/efi.h> > > > +#include <asm/sections.h> > > > + > > > +#include "efistub.h" > > > +/* > > > + * RISCV requires the kernel image to placed TEXT_OFFSET bytes beyond a 2 MB > > > + * aligned base for 64 bit and 4MB for 32 bit. > > > + */ > > Fixed the comment. > > > > +#ifdef CONFIG_64BIT > > > +#define MIN_KIMG_ALIGN SZ_2M > > > +#else > > > +#define MIN_KIMG_ALIGN SZ_4M > > > +#endif > > > + > > > +typedef __attribute__((noreturn)) void (*jump_kernel_func)(unsigned int, > > > + unsigned long); > > > +efi_status_t check_platform_features(void) > > > +{ > > > + return EFI_SUCCESS; > > > +} > > > + > > > +static u32 get_boot_hartid_from_fdt(unsigned long fdt) > > > +{ > > > + int chosen_node, len; > > > + const fdt32_t *prop; > > > + > > > + chosen_node = fdt_path_offset((void *)fdt, "/chosen"); > > > + if (chosen_node < 0) > > > + return U32_MAX; > > > + prop = fdt_getprop((void *)fdt, chosen_node, "boot-hartid", &len); > > > + if (!prop || len != sizeof(u32)) > > > + return U32_MAX; > > > + > > > + return fdt32_to_cpu(*prop); > > > +} > > > + > > > +/* > > > + * Jump to real kernel here with following constraints. > > > + * 1. MMU should be disabled. > > > + * 2. a0 should contain hartid > > > + * 3. a1 should DT address > > > + */ > > > +void __noreturn efi_enter_kernel(unsigned long entrypoint, unsigned long fdt, > > > + unsigned long fdt_size) > > > +{ > > > + unsigned long kernel_entry = entrypoint + (unsigned long)stext_offset; > > > + jump_kernel_func jump_kernel = (jump_kernel_func) kernel_entry; > > > + u32 hartid = get_boot_hartid_from_fdt(fdt); > > > + > > > + if (hartid == U32_MAX) > > > + /* We can not use panic or BUG at this point */ > > > + __asm__ __volatile__ ("ebreak"); > > > + /* Disable MMU */ > > > + csr_write(CSR_SATP, 0); > > > + jump_kernel(hartid, fdt); > > > +} > > > + > > > +efi_status_t handle_kernel_image(unsigned long *image_addr, > > > + unsigned long *image_size, > > > + unsigned long *reserve_addr, > > > + unsigned long *reserve_size, > > > + unsigned long dram_base, > > > + efi_loaded_image_t *image) > > > +{ > > > + efi_status_t status; > > > + unsigned long kernel_size, kernel_memsize = 0; > > > + unsigned long max_alloc_address; > > > + > > > + if (image->image_base != _start) > > > + pr_efi_err("FIRMWARE BUG: efi_loaded_image_t::image_base has bogus value\n"); > > > + > > > > I don't think you need this. > > > > Sure. I will remove it. I guess ARM64 code has the error print for > legacy loader code ? > No, for broken distro versions of GRUB > > > + kernel_size = _edata - _start; > > > + kernel_memsize = kernel_size + (_end - _edata); > > > + max_alloc_address = round_up(dram_base, MIN_KIMG_ALIGN) + > > > + kernel_memsize; > > > + > > > > You said the kernel could be anywhere in memory, as long as it is > > aligned correctly, right? > > Sorry I was wrong about this. RISC-V kernel maps PAGE_OFFSET virtual > address to the > physical address <xyz> where it is booted. That means memory between > dram start and and <xyz> address > will be unusable. > OK > I also realized that the above computing max_address as above also > won't work for the following reason. > efi_allocate_pages_aligned actually ALIGN_DOWN the max_address. Thus, > efi won't find enough > free memory in this case if the max_address is computed from the dram_base. > > Is there an implicit requirement for efi_allocate_pages_aligned or > efi_low_alloc_above should be tried in case of failure? > No not really. What ever works for your particular use case is acceptable to me. > > In that case, you don't need this, you can simply pass ULONG_MAX as > > the max address. > > > As RISC-V should allocate memory as low as possible to avoid memory > wastage, I think the following should work. > > efi_low_alloc_above(*reserve_size, MIN_KIMG_ALIGN, reserve_addr, dram_base); > > If this looks okay to you, efi_low_alloc_above should be moved back to > mem.c from relocate.c. > Should I do it in a separate patch or the original patch should be > modified so that efi_low_alloc_above was never moved to relocate.c > No, please keep efi_low_alloc_above() where it is, but drop the static, and put back the declaration in efistub.h > > > + if (IS_ALIGNED((u64)_start, MIN_KIMG_ALIGN)) { > > > + /* > > > + * Just execute from wherever we were loaded by the > > > + * UEFI PE/COFF loader if the alignment is suitable. > > > + */ > > > + *image_addr = (u64)_start; > > > > Change these casts to (unsigned long), as reported by the robot. > > > Done. > > > So you no longer need the placement to be TEXT_OFFSET bytes past a > > MIN_KIMG_ALIGN aligned boundary, right? > > > > Nope. EFI memory marked the firmware area as reserved. So EFI memory > allocator will make sure that > it never allocates memory from that region. > OK, good. > > > + *reserve_size = 0; > > > + return EFI_SUCCESS; > > > + } > > > + status = efi_allocate_pages_aligned(*reserve_size, reserve_addr, > > > + max_alloc_address, MIN_KIMG_ALIGN); > > > + > > > + if (status != EFI_SUCCESS) { > > > + pr_efi_err("Failed to relocate kernel\n"); > > > + *reserve_size = 0; > > > + return status; > > > + } > > > + *image_addr = *reserve_addr; > > > + > > > + memcpy((void *)*image_addr, _start, kernel_size); > > > + > > > + return EFI_SUCCESS; > > > +} > > > -- > > > 2.24.0 > > > > > > > _______________________________________________ > > linux-arm-kernel mailing list > > linux-arm-kernel@lists.infradead.org > > http://lists.infradead.org/mailman/listinfo/linux-arm-kernel > > > > -- > Regards, > Atish
On Sat, 18 Apr 2020 at 12:51, Ard Biesheuvel <ardb@kernel.org> wrote: > > On Sat, 18 Apr 2020 at 05:03, Atish Patra <atishp@atishpatra.org> wrote: > > > > On Thu, Apr 16, 2020 at 12:41 AM Ard Biesheuvel <ardb@kernel.org> wrote: > > > > > > On Wed, 15 Apr 2020 at 21:54, Atish Patra <atish.patra@wdc.com> wrote: > > > > > > > > Add a RISC-V architecture specific stub code that actually copies the > > > > actual kernel image to a valid address and jump to it after boot services > > > > are terminated. Enable UEFI related kernel configs as well for RISC-V. > > > > > > > > Signed-off-by: Atish Patra <atish.patra@wdc.com> > > > > --- > > > > arch/riscv/Kconfig | 20 ++++ > > > > arch/riscv/Makefile | 1 + > > > > arch/riscv/configs/defconfig | 1 + > > > > arch/riscv/include/asm/efi.h | 44 +++++++++ > > > > drivers/firmware/efi/Kconfig | 2 +- > > > > drivers/firmware/efi/libstub/Makefile | 7 ++ > > > > drivers/firmware/efi/libstub/riscv-stub.c | 111 ++++++++++++++++++++++ > > > > 7 files changed, 185 insertions(+), 1 deletion(-) > > > > create mode 100644 arch/riscv/include/asm/efi.h > > > > create mode 100644 drivers/firmware/efi/libstub/riscv-stub.c > > > > > > > > diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig > > > > index f39e326a7a42..eb4f41c8f3ce 100644 > > > > --- a/arch/riscv/Kconfig > > > > +++ b/arch/riscv/Kconfig > > > > @@ -379,10 +379,30 @@ config CMDLINE_FORCE > > > > > > > > endchoice > > > > > > > > +config EFI_STUB > > > > + bool > > > > + > > > > +config EFI > > > > + bool "UEFI runtime support" > > > > + depends on OF > > > > + select LIBFDT > > > > + select UCS2_STRING > > > > + select EFI_PARAMS_FROM_FDT > > > > + select EFI_STUB > > > > + select EFI_GENERIC_STUB > > > > + default y > > > > + help > > > > + This option provides support for runtime services provided > > > > + by UEFI firmware (such as non-volatile variables, realtime > > > > + clock, and platform reset). A UEFI stub is also provided to > > > > + allow the kernel to be booted as an EFI application. This > > > > + is only useful on systems that have UEFI firmware. > > > > + > > > > endmenu > > > > > > > > menu "Power management options" > > > > > > > > source "kernel/power/Kconfig" > > > > +source "drivers/firmware/Kconfig" > > > > > > > > endmenu > > > > diff --git a/arch/riscv/Makefile b/arch/riscv/Makefile > > > > index fb6e37db836d..079435804d6d 100644 > > > > --- a/arch/riscv/Makefile > > > > +++ b/arch/riscv/Makefile > > > > @@ -80,6 +80,7 @@ head-y := arch/riscv/kernel/head.o > > > > core-y += arch/riscv/ > > > > > > > > libs-y += arch/riscv/lib/ > > > > +core-$(CONFIG_EFI_STUB) += $(objtree)/drivers/firmware/efi/libstub/lib.a > > > > > > > > PHONY += vdso_install > > > > vdso_install: > > > > diff --git a/arch/riscv/configs/defconfig b/arch/riscv/configs/defconfig > > > > index 4da4886246a4..ae69e12d306a 100644 > > > > --- a/arch/riscv/configs/defconfig > > > > +++ b/arch/riscv/configs/defconfig > > > > @@ -129,3 +129,4 @@ CONFIG_DEBUG_BLOCK_EXT_DEVT=y > > > > # CONFIG_RUNTIME_TESTING_MENU is not set > > > > CONFIG_MEMTEST=y > > > > # CONFIG_SYSFS_SYSCALL is not set > > > > +CONFIG_EFI=y > > > > diff --git a/arch/riscv/include/asm/efi.h b/arch/riscv/include/asm/efi.h > > > > new file mode 100644 > > > > index 000000000000..62d7d5eafed8 > > > > --- /dev/null > > > > +++ b/arch/riscv/include/asm/efi.h > > > > @@ -0,0 +1,44 @@ > > > > +/* SPDX-License-Identifier: GPL-2.0 */ > > > > +/* > > > > + * Copyright (C) 2020 Western Digital Corporation or its affiliates. > > > > + * Based on arch/arm64/include/asm/efi.h > > > > + */ > > > > +#ifndef _ASM_EFI_H > > > > +#define _ASM_EFI_H > > > > + > > > > +#include <asm/io.h> > > > > +#include <asm/mmu_context.h> > > > > +#include <asm/ptrace.h> > > > > +#include <asm/tlbflush.h> > > > > + > > > > +#define VA_BITS_MIN 39 > > > > + > > > > +/* on RISC-V, the FDT may be located anywhere in system RAM */ > > > > +static inline unsigned long efi_get_max_fdt_addr(unsigned long dram_base) > > > > +{ > > > > + return ULONG_MAX; > > > > +} > > > > + > > > > +/* Load initrd at enough distance from DRAM start */ > > > > +static inline unsigned long efi_get_max_initrd_addr(unsigned long dram_base, > > > > + unsigned long image_addr) > > > > +{ > > > > + return dram_base + SZ_256M; > > > > +} > > > > + > > > > +#define efi_bs_call(func, ...) efi_system_table()->boottime->func(__VA_ARGS__) > > > > +#define efi_rt_call(func, ...) efi_system_table()->runtime->func(__VA_ARGS__) > > > > +#define efi_is_native() (true) > > > > + > > > > +#define efi_table_attr(inst, attr) (inst->attr) > > > > + > > > > +#define efi_call_proto(inst, func, ...) inst->func(inst, ##__VA_ARGS__) > > > > + > > > > +#define alloc_screen_info(x...) (&screen_info) > > > > +extern char stext_offset[]; > > > > + > > > > +static inline void free_screen_info(struct screen_info *si) > > > > +{ > > > > +} > > > > + > > > > +#endif /* _ASM_EFI_H */ > > > > diff --git a/drivers/firmware/efi/Kconfig b/drivers/firmware/efi/Kconfig > > > > index 2a2b2b96a1dc..fcdc789d3f87 100644 > > > > --- a/drivers/firmware/efi/Kconfig > > > > +++ b/drivers/firmware/efi/Kconfig > > > > @@ -111,7 +111,7 @@ config EFI_GENERIC_STUB > > > > > > > > config EFI_ARMSTUB_DTB_LOADER > > > > bool "Enable the DTB loader" > > > > - depends on EFI_GENERIC_STUB > > > > + depends on EFI_GENERIC_STUB && !RISCV > > > > default y > > > > help > > > > Select this config option to add support for the dtb= command > > > > diff --git a/drivers/firmware/efi/libstub/Makefile b/drivers/firmware/efi/libstub/Makefile > > > > index 2b4e09bf987c..7d46b70b51f2 100644 > > > > --- a/drivers/firmware/efi/libstub/Makefile > > > > +++ b/drivers/firmware/efi/libstub/Makefile > > > > @@ -22,6 +22,8 @@ cflags-$(CONFIG_ARM64) := $(subst $(CC_FLAGS_FTRACE),,$(KBUILD_CFLAGS)) \ > > > > cflags-$(CONFIG_ARM) := $(subst $(CC_FLAGS_FTRACE),,$(KBUILD_CFLAGS)) \ > > > > -fno-builtin -fpic \ > > > > $(call cc-option,-mno-single-pic-base) > > > > +cflags-$(CONFIG_RISCV) := $(subst $(CC_FLAGS_FTRACE),,$(KBUILD_CFLAGS)) \ > > > > + -fpic > > > > > > > > cflags-$(CONFIG_EFI_GENERIC_STUB) += -I$(srctree)/scripts/dtc/libfdt > > > > > > > > @@ -57,6 +59,7 @@ lib-$(CONFIG_EFI_GENERIC_STUB) += efi-stub.o fdt.o string.o \ > > > > lib-$(CONFIG_ARM) += arm32-stub.o > > > > lib-$(CONFIG_ARM64) += arm64-stub.o > > > > lib-$(CONFIG_X86) += x86-stub.o > > > > +lib-$(CONFIG_RISCV) += riscv-stub.o > > > > CFLAGS_arm32-stub.o := -DTEXT_OFFSET=$(TEXT_OFFSET) > > > > CFLAGS_arm64-stub.o := -DTEXT_OFFSET=$(TEXT_OFFSET) > > > > > > > > @@ -81,6 +84,10 @@ STUBCOPY_FLAGS-$(CONFIG_ARM64) += --prefix-alloc-sections=.init \ > > > > --prefix-symbols=__efistub_ > > > > STUBCOPY_RELOC-$(CONFIG_ARM64) := R_AARCH64_ABS > > > > > > > > +STUBCOPY_FLAGS-$(CONFIG_RISCV) += --prefix-alloc-sections=.init \ > > > > + --prefix-symbols=__efistub_ > > > > +STUBCOPY_RELOC-$(CONFIG_RISCV) := R_RISCV_HI20 > > > > + > > > > $(obj)/%.stub.o: $(obj)/%.o FORCE > > > > $(call if_changed,stubcopy) > > > > > > > > diff --git a/drivers/firmware/efi/libstub/riscv-stub.c b/drivers/firmware/efi/libstub/riscv-stub.c > > > > new file mode 100644 > > > > index 000000000000..69d13e0ebaea > > > > --- /dev/null > > > > +++ b/drivers/firmware/efi/libstub/riscv-stub.c > > > > @@ -0,0 +1,111 @@ > > > > +// SPDX-License-Identifier: GPL-2.0 > > > > +/* > > > > + * Copyright (C) 2013, 2014 Linaro Ltd; <roy.franz@linaro.org> > > > > + * Copyright (C) 2020 Western Digital Corporation or its affiliates. > > > > + * > > > > + * This file implements the EFI boot stub for the RISC-V kernel. > > > > + * Adapted from ARM64 version at drivers/firmware/efi/libstub/arm64-stub.c. > > > > + */ > > > > + > > > > +#include <linux/efi.h> > > > > +#include <linux/libfdt.h> > > > > +#include <linux/libfdt_env.h> > > > > +#include <asm/efi.h> > > > > +#include <asm/sections.h> > > > > + > > > > +#include "efistub.h" > > > > +/* > > > > + * RISCV requires the kernel image to placed TEXT_OFFSET bytes beyond a 2 MB > > > > + * aligned base for 64 bit and 4MB for 32 bit. > > > > + */ > > > > Fixed the comment. > > > > > > +#ifdef CONFIG_64BIT > > > > +#define MIN_KIMG_ALIGN SZ_2M > > > > +#else > > > > +#define MIN_KIMG_ALIGN SZ_4M > > > > +#endif > > > > + > > > > +typedef __attribute__((noreturn)) void (*jump_kernel_func)(unsigned int, > > > > + unsigned long); > > > > +efi_status_t check_platform_features(void) > > > > +{ > > > > + return EFI_SUCCESS; > > > > +} > > > > + > > > > +static u32 get_boot_hartid_from_fdt(unsigned long fdt) > > > > +{ > > > > + int chosen_node, len; > > > > + const fdt32_t *prop; > > > > + > > > > + chosen_node = fdt_path_offset((void *)fdt, "/chosen"); > > > > + if (chosen_node < 0) > > > > + return U32_MAX; > > > > + prop = fdt_getprop((void *)fdt, chosen_node, "boot-hartid", &len); > > > > + if (!prop || len != sizeof(u32)) > > > > + return U32_MAX; > > > > + > > > > + return fdt32_to_cpu(*prop); > > > > +} > > > > + > > > > +/* > > > > + * Jump to real kernel here with following constraints. > > > > + * 1. MMU should be disabled. > > > > + * 2. a0 should contain hartid > > > > + * 3. a1 should DT address > > > > + */ > > > > +void __noreturn efi_enter_kernel(unsigned long entrypoint, unsigned long fdt, > > > > + unsigned long fdt_size) > > > > +{ > > > > + unsigned long kernel_entry = entrypoint + (unsigned long)stext_offset; > > > > + jump_kernel_func jump_kernel = (jump_kernel_func) kernel_entry; > > > > + u32 hartid = get_boot_hartid_from_fdt(fdt); > > > > + > > > > + if (hartid == U32_MAX) > > > > + /* We can not use panic or BUG at this point */ > > > > + __asm__ __volatile__ ("ebreak"); > > > > + /* Disable MMU */ > > > > + csr_write(CSR_SATP, 0); > > > > + jump_kernel(hartid, fdt); > > > > +} > > > > + > > > > +efi_status_t handle_kernel_image(unsigned long *image_addr, > > > > + unsigned long *image_size, > > > > + unsigned long *reserve_addr, > > > > + unsigned long *reserve_size, > > > > + unsigned long dram_base, > > > > + efi_loaded_image_t *image) > > > > +{ > > > > + efi_status_t status; > > > > + unsigned long kernel_size, kernel_memsize = 0; > > > > + unsigned long max_alloc_address; > > > > + > > > > + if (image->image_base != _start) > > > > + pr_efi_err("FIRMWARE BUG: efi_loaded_image_t::image_base has bogus value\n"); > > > > + > > > > > > I don't think you need this. > > > > > > > Sure. I will remove it. I guess ARM64 code has the error print for > > legacy loader code ? > > > > No, for broken distro versions of GRUB > > > > > + kernel_size = _edata - _start; > > > > + kernel_memsize = kernel_size + (_end - _edata); > > > > + max_alloc_address = round_up(dram_base, MIN_KIMG_ALIGN) + > > > > + kernel_memsize; > > > > + > > > > > > You said the kernel could be anywhere in memory, as long as it is > > > aligned correctly, right? > > > > Sorry I was wrong about this. RISC-V kernel maps PAGE_OFFSET virtual > > address to the > > physical address <xyz> where it is booted. That means memory between > > dram start and and <xyz> address > > will be unusable. > > > > OK > > > I also realized that the above computing max_address as above also > > won't work for the following reason. > > efi_allocate_pages_aligned actually ALIGN_DOWN the max_address. Thus, > > efi won't find enough > > free memory in this case if the max_address is computed from the dram_base. > > > > Is there an implicit requirement for efi_allocate_pages_aligned or > > efi_low_alloc_above should be tried in case of failure? > > > > No not really. What ever works for your particular use case is acceptable to me. > > > > In that case, you don't need this, you can simply pass ULONG_MAX as > > > the max address. > > > > > As RISC-V should allocate memory as low as possible to avoid memory > > wastage, I think the following should work. > > > > efi_low_alloc_above(*reserve_size, MIN_KIMG_ALIGN, reserve_addr, dram_base); > > > > If this looks okay to you, efi_low_alloc_above should be moved back to > > mem.c from relocate.c. > > Should I do it in a separate patch or the original patch should be > > modified so that efi_low_alloc_above was never moved to relocate.c > > > > No, please keep efi_low_alloc_above() where it is, but drop the > static, and put back the declaration in efistub.h > Alternatively, can you check whether efi_relocate_kernel() already does what you need?
On Sat, Apr 18, 2020 at 5:39 AM Ard Biesheuvel <ardb@kernel.org> wrote: > > On Sat, 18 Apr 2020 at 12:51, Ard Biesheuvel <ardb@kernel.org> wrote: > > > > On Sat, 18 Apr 2020 at 05:03, Atish Patra <atishp@atishpatra.org> wrote: > > > > > > On Thu, Apr 16, 2020 at 12:41 AM Ard Biesheuvel <ardb@kernel.org> wrote: > > > > > > > > On Wed, 15 Apr 2020 at 21:54, Atish Patra <atish.patra@wdc.com> wrote: > > > > > > > > > > Add a RISC-V architecture specific stub code that actually copies the > > > > > actual kernel image to a valid address and jump to it after boot services > > > > > are terminated. Enable UEFI related kernel configs as well for RISC-V. > > > > > > > > > > Signed-off-by: Atish Patra <atish.patra@wdc.com> > > > > > --- > > > > > arch/riscv/Kconfig | 20 ++++ > > > > > arch/riscv/Makefile | 1 + > > > > > arch/riscv/configs/defconfig | 1 + > > > > > arch/riscv/include/asm/efi.h | 44 +++++++++ > > > > > drivers/firmware/efi/Kconfig | 2 +- > > > > > drivers/firmware/efi/libstub/Makefile | 7 ++ > > > > > drivers/firmware/efi/libstub/riscv-stub.c | 111 ++++++++++++++++++++++ > > > > > 7 files changed, 185 insertions(+), 1 deletion(-) > > > > > create mode 100644 arch/riscv/include/asm/efi.h > > > > > create mode 100644 drivers/firmware/efi/libstub/riscv-stub.c > > > > > > > > > > diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig > > > > > index f39e326a7a42..eb4f41c8f3ce 100644 > > > > > --- a/arch/riscv/Kconfig > > > > > +++ b/arch/riscv/Kconfig > > > > > @@ -379,10 +379,30 @@ config CMDLINE_FORCE > > > > > > > > > > endchoice > > > > > > > > > > +config EFI_STUB > > > > > + bool > > > > > + > > > > > +config EFI > > > > > + bool "UEFI runtime support" > > > > > + depends on OF > > > > > + select LIBFDT > > > > > + select UCS2_STRING > > > > > + select EFI_PARAMS_FROM_FDT > > > > > + select EFI_STUB > > > > > + select EFI_GENERIC_STUB > > > > > + default y > > > > > + help > > > > > + This option provides support for runtime services provided > > > > > + by UEFI firmware (such as non-volatile variables, realtime > > > > > + clock, and platform reset). A UEFI stub is also provided to > > > > > + allow the kernel to be booted as an EFI application. This > > > > > + is only useful on systems that have UEFI firmware. > > > > > + > > > > > endmenu > > > > > > > > > > menu "Power management options" > > > > > > > > > > source "kernel/power/Kconfig" > > > > > +source "drivers/firmware/Kconfig" > > > > > > > > > > endmenu > > > > > diff --git a/arch/riscv/Makefile b/arch/riscv/Makefile > > > > > index fb6e37db836d..079435804d6d 100644 > > > > > --- a/arch/riscv/Makefile > > > > > +++ b/arch/riscv/Makefile > > > > > @@ -80,6 +80,7 @@ head-y := arch/riscv/kernel/head.o > > > > > core-y += arch/riscv/ > > > > > > > > > > libs-y += arch/riscv/lib/ > > > > > +core-$(CONFIG_EFI_STUB) += $(objtree)/drivers/firmware/efi/libstub/lib.a > > > > > > > > > > PHONY += vdso_install > > > > > vdso_install: > > > > > diff --git a/arch/riscv/configs/defconfig b/arch/riscv/configs/defconfig > > > > > index 4da4886246a4..ae69e12d306a 100644 > > > > > --- a/arch/riscv/configs/defconfig > > > > > +++ b/arch/riscv/configs/defconfig > > > > > @@ -129,3 +129,4 @@ CONFIG_DEBUG_BLOCK_EXT_DEVT=y > > > > > # CONFIG_RUNTIME_TESTING_MENU is not set > > > > > CONFIG_MEMTEST=y > > > > > # CONFIG_SYSFS_SYSCALL is not set > > > > > +CONFIG_EFI=y > > > > > diff --git a/arch/riscv/include/asm/efi.h b/arch/riscv/include/asm/efi.h > > > > > new file mode 100644 > > > > > index 000000000000..62d7d5eafed8 > > > > > --- /dev/null > > > > > +++ b/arch/riscv/include/asm/efi.h > > > > > @@ -0,0 +1,44 @@ > > > > > +/* SPDX-License-Identifier: GPL-2.0 */ > > > > > +/* > > > > > + * Copyright (C) 2020 Western Digital Corporation or its affiliates. > > > > > + * Based on arch/arm64/include/asm/efi.h > > > > > + */ > > > > > +#ifndef _ASM_EFI_H > > > > > +#define _ASM_EFI_H > > > > > + > > > > > +#include <asm/io.h> > > > > > +#include <asm/mmu_context.h> > > > > > +#include <asm/ptrace.h> > > > > > +#include <asm/tlbflush.h> > > > > > + > > > > > +#define VA_BITS_MIN 39 > > > > > + > > > > > +/* on RISC-V, the FDT may be located anywhere in system RAM */ > > > > > +static inline unsigned long efi_get_max_fdt_addr(unsigned long dram_base) > > > > > +{ > > > > > + return ULONG_MAX; > > > > > +} > > > > > + > > > > > +/* Load initrd at enough distance from DRAM start */ > > > > > +static inline unsigned long efi_get_max_initrd_addr(unsigned long dram_base, > > > > > + unsigned long image_addr) > > > > > +{ > > > > > + return dram_base + SZ_256M; > > > > > +} > > > > > + > > > > > +#define efi_bs_call(func, ...) efi_system_table()->boottime->func(__VA_ARGS__) > > > > > +#define efi_rt_call(func, ...) efi_system_table()->runtime->func(__VA_ARGS__) > > > > > +#define efi_is_native() (true) > > > > > + > > > > > +#define efi_table_attr(inst, attr) (inst->attr) > > > > > + > > > > > +#define efi_call_proto(inst, func, ...) inst->func(inst, ##__VA_ARGS__) > > > > > + > > > > > +#define alloc_screen_info(x...) (&screen_info) > > > > > +extern char stext_offset[]; > > > > > + > > > > > +static inline void free_screen_info(struct screen_info *si) > > > > > +{ > > > > > +} > > > > > + > > > > > +#endif /* _ASM_EFI_H */ > > > > > diff --git a/drivers/firmware/efi/Kconfig b/drivers/firmware/efi/Kconfig > > > > > index 2a2b2b96a1dc..fcdc789d3f87 100644 > > > > > --- a/drivers/firmware/efi/Kconfig > > > > > +++ b/drivers/firmware/efi/Kconfig > > > > > @@ -111,7 +111,7 @@ config EFI_GENERIC_STUB > > > > > > > > > > config EFI_ARMSTUB_DTB_LOADER > > > > > bool "Enable the DTB loader" > > > > > - depends on EFI_GENERIC_STUB > > > > > + depends on EFI_GENERIC_STUB && !RISCV > > > > > default y > > > > > help > > > > > Select this config option to add support for the dtb= command > > > > > diff --git a/drivers/firmware/efi/libstub/Makefile b/drivers/firmware/efi/libstub/Makefile > > > > > index 2b4e09bf987c..7d46b70b51f2 100644 > > > > > --- a/drivers/firmware/efi/libstub/Makefile > > > > > +++ b/drivers/firmware/efi/libstub/Makefile > > > > > @@ -22,6 +22,8 @@ cflags-$(CONFIG_ARM64) := $(subst $(CC_FLAGS_FTRACE),,$(KBUILD_CFLAGS)) \ > > > > > cflags-$(CONFIG_ARM) := $(subst $(CC_FLAGS_FTRACE),,$(KBUILD_CFLAGS)) \ > > > > > -fno-builtin -fpic \ > > > > > $(call cc-option,-mno-single-pic-base) > > > > > +cflags-$(CONFIG_RISCV) := $(subst $(CC_FLAGS_FTRACE),,$(KBUILD_CFLAGS)) \ > > > > > + -fpic > > > > > > > > > > cflags-$(CONFIG_EFI_GENERIC_STUB) += -I$(srctree)/scripts/dtc/libfdt > > > > > > > > > > @@ -57,6 +59,7 @@ lib-$(CONFIG_EFI_GENERIC_STUB) += efi-stub.o fdt.o string.o \ > > > > > lib-$(CONFIG_ARM) += arm32-stub.o > > > > > lib-$(CONFIG_ARM64) += arm64-stub.o > > > > > lib-$(CONFIG_X86) += x86-stub.o > > > > > +lib-$(CONFIG_RISCV) += riscv-stub.o > > > > > CFLAGS_arm32-stub.o := -DTEXT_OFFSET=$(TEXT_OFFSET) > > > > > CFLAGS_arm64-stub.o := -DTEXT_OFFSET=$(TEXT_OFFSET) > > > > > > > > > > @@ -81,6 +84,10 @@ STUBCOPY_FLAGS-$(CONFIG_ARM64) += --prefix-alloc-sections=.init \ > > > > > --prefix-symbols=__efistub_ > > > > > STUBCOPY_RELOC-$(CONFIG_ARM64) := R_AARCH64_ABS > > > > > > > > > > +STUBCOPY_FLAGS-$(CONFIG_RISCV) += --prefix-alloc-sections=.init \ > > > > > + --prefix-symbols=__efistub_ > > > > > +STUBCOPY_RELOC-$(CONFIG_RISCV) := R_RISCV_HI20 > > > > > + > > > > > $(obj)/%.stub.o: $(obj)/%.o FORCE > > > > > $(call if_changed,stubcopy) > > > > > > > > > > diff --git a/drivers/firmware/efi/libstub/riscv-stub.c b/drivers/firmware/efi/libstub/riscv-stub.c > > > > > new file mode 100644 > > > > > index 000000000000..69d13e0ebaea > > > > > --- /dev/null > > > > > +++ b/drivers/firmware/efi/libstub/riscv-stub.c > > > > > @@ -0,0 +1,111 @@ > > > > > +// SPDX-License-Identifier: GPL-2.0 > > > > > +/* > > > > > + * Copyright (C) 2013, 2014 Linaro Ltd; <roy.franz@linaro.org> > > > > > + * Copyright (C) 2020 Western Digital Corporation or its affiliates. > > > > > + * > > > > > + * This file implements the EFI boot stub for the RISC-V kernel. > > > > > + * Adapted from ARM64 version at drivers/firmware/efi/libstub/arm64-stub.c. > > > > > + */ > > > > > + > > > > > +#include <linux/efi.h> > > > > > +#include <linux/libfdt.h> > > > > > +#include <linux/libfdt_env.h> > > > > > +#include <asm/efi.h> > > > > > +#include <asm/sections.h> > > > > > + > > > > > +#include "efistub.h" > > > > > +/* > > > > > + * RISCV requires the kernel image to placed TEXT_OFFSET bytes beyond a 2 MB > > > > > + * aligned base for 64 bit and 4MB for 32 bit. > > > > > + */ > > > > > > Fixed the comment. > > > > > > > > +#ifdef CONFIG_64BIT > > > > > +#define MIN_KIMG_ALIGN SZ_2M > > > > > +#else > > > > > +#define MIN_KIMG_ALIGN SZ_4M > > > > > +#endif > > > > > + > > > > > +typedef __attribute__((noreturn)) void (*jump_kernel_func)(unsigned int, > > > > > + unsigned long); > > > > > +efi_status_t check_platform_features(void) > > > > > +{ > > > > > + return EFI_SUCCESS; > > > > > +} > > > > > + > > > > > +static u32 get_boot_hartid_from_fdt(unsigned long fdt) > > > > > +{ > > > > > + int chosen_node, len; > > > > > + const fdt32_t *prop; > > > > > + > > > > > + chosen_node = fdt_path_offset((void *)fdt, "/chosen"); > > > > > + if (chosen_node < 0) > > > > > + return U32_MAX; > > > > > + prop = fdt_getprop((void *)fdt, chosen_node, "boot-hartid", &len); > > > > > + if (!prop || len != sizeof(u32)) > > > > > + return U32_MAX; > > > > > + > > > > > + return fdt32_to_cpu(*prop); > > > > > +} > > > > > + > > > > > +/* > > > > > + * Jump to real kernel here with following constraints. > > > > > + * 1. MMU should be disabled. > > > > > + * 2. a0 should contain hartid > > > > > + * 3. a1 should DT address > > > > > + */ > > > > > +void __noreturn efi_enter_kernel(unsigned long entrypoint, unsigned long fdt, > > > > > + unsigned long fdt_size) > > > > > +{ > > > > > + unsigned long kernel_entry = entrypoint + (unsigned long)stext_offset; > > > > > + jump_kernel_func jump_kernel = (jump_kernel_func) kernel_entry; > > > > > + u32 hartid = get_boot_hartid_from_fdt(fdt); > > > > > + > > > > > + if (hartid == U32_MAX) > > > > > + /* We can not use panic or BUG at this point */ > > > > > + __asm__ __volatile__ ("ebreak"); > > > > > + /* Disable MMU */ > > > > > + csr_write(CSR_SATP, 0); > > > > > + jump_kernel(hartid, fdt); > > > > > +} > > > > > + > > > > > +efi_status_t handle_kernel_image(unsigned long *image_addr, > > > > > + unsigned long *image_size, > > > > > + unsigned long *reserve_addr, > > > > > + unsigned long *reserve_size, > > > > > + unsigned long dram_base, > > > > > + efi_loaded_image_t *image) > > > > > +{ > > > > > + efi_status_t status; > > > > > + unsigned long kernel_size, kernel_memsize = 0; > > > > > + unsigned long max_alloc_address; > > > > > + > > > > > + if (image->image_base != _start) > > > > > + pr_efi_err("FIRMWARE BUG: efi_loaded_image_t::image_base has bogus value\n"); > > > > > + > > > > > > > > I don't think you need this. > > > > > > > > > > Sure. I will remove it. I guess ARM64 code has the error print for > > > legacy loader code ? > > > > > > > No, for broken distro versions of GRUB > > > > > > > + kernel_size = _edata - _start; > > > > > + kernel_memsize = kernel_size + (_end - _edata); > > > > > + max_alloc_address = round_up(dram_base, MIN_KIMG_ALIGN) + > > > > > + kernel_memsize; > > > > > + > > > > > > > > You said the kernel could be anywhere in memory, as long as it is > > > > aligned correctly, right? > > > > > > Sorry I was wrong about this. RISC-V kernel maps PAGE_OFFSET virtual > > > address to the > > > physical address <xyz> where it is booted. That means memory between > > > dram start and and <xyz> address > > > will be unusable. > > > > > > > OK > > > > > I also realized that the above computing max_address as above also > > > won't work for the following reason. > > > efi_allocate_pages_aligned actually ALIGN_DOWN the max_address. Thus, > > > efi won't find enough > > > free memory in this case if the max_address is computed from the dram_base. > > > > > > Is there an implicit requirement for efi_allocate_pages_aligned or > > > efi_low_alloc_above should be tried in case of failure? > > > > > > > No not really. What ever works for your particular use case is acceptable to me. > > > > > > In that case, you don't need this, you can simply pass ULONG_MAX as > > > > the max address. > > > > > > > As RISC-V should allocate memory as low as possible to avoid memory > > > wastage, I think the following should work. > > > > > > efi_low_alloc_above(*reserve_size, MIN_KIMG_ALIGN, reserve_addr, dram_base); > > > > > > If this looks okay to you, efi_low_alloc_above should be moved back to > > > mem.c from relocate.c. > > > Should I do it in a separate patch or the original patch should be > > > modified so that efi_low_alloc_above was never moved to relocate.c > > > > > > > No, please keep efi_low_alloc_above() where it is, but drop the > > static, and put back the declaration in efistub.h > > > > Alternatively, can you check whether efi_relocate_kernel() already > does what you need? Yeah. efi_relocate_kernel works too. It's just that efi_relocate_kernel expects a preferred address which RISC-V doesn't care about. I can pass ULONG_MAX so that efi_bs_call will fail and efi_low_alloc_above will be invoked eventually. I am also thinking to put a check in relocate_kernel for preferred address != ULONG_MAX to avoid an extra efi_bs_call. The extra call doesn't actually create an issue, just a minor optimization. But if that is not acceptable for generic code, that is fine as well. Thanks for your suggestions and time.
On Sat, 18 Apr 2020 at 21:19, Atish Patra <atishp@atishpatra.org> wrote: > > On Sat, Apr 18, 2020 at 5:39 AM Ard Biesheuvel <ardb@kernel.org> wrote: > > > > On Sat, 18 Apr 2020 at 12:51, Ard Biesheuvel <ardb@kernel.org> wrote: > > > > > > On Sat, 18 Apr 2020 at 05:03, Atish Patra <atishp@atishpatra.org> wrote: > > > > > > > > On Thu, Apr 16, 2020 at 12:41 AM Ard Biesheuvel <ardb@kernel.org> wrote: > > > > > > > > > > On Wed, 15 Apr 2020 at 21:54, Atish Patra <atish.patra@wdc.com> wrote: > > > > > > > > > > > > Add a RISC-V architecture specific stub code that actually copies the > > > > > > actual kernel image to a valid address and jump to it after boot services > > > > > > are terminated. Enable UEFI related kernel configs as well for RISC-V. > > > > > > > > > > > > Signed-off-by: Atish Patra <atish.patra@wdc.com> > > > > > > --- > > > > > > arch/riscv/Kconfig | 20 ++++ > > > > > > arch/riscv/Makefile | 1 + > > > > > > arch/riscv/configs/defconfig | 1 + > > > > > > arch/riscv/include/asm/efi.h | 44 +++++++++ > > > > > > drivers/firmware/efi/Kconfig | 2 +- > > > > > > drivers/firmware/efi/libstub/Makefile | 7 ++ > > > > > > drivers/firmware/efi/libstub/riscv-stub.c | 111 ++++++++++++++++++++++ > > > > > > 7 files changed, 185 insertions(+), 1 deletion(-) > > > > > > create mode 100644 arch/riscv/include/asm/efi.h > > > > > > create mode 100644 drivers/firmware/efi/libstub/riscv-stub.c > > > > > > > > > > > > diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig > > > > > > index f39e326a7a42..eb4f41c8f3ce 100644 > > > > > > --- a/arch/riscv/Kconfig > > > > > > +++ b/arch/riscv/Kconfig > > > > > > @@ -379,10 +379,30 @@ config CMDLINE_FORCE > > > > > > > > > > > > endchoice > > > > > > > > > > > > +config EFI_STUB > > > > > > + bool > > > > > > + > > > > > > +config EFI > > > > > > + bool "UEFI runtime support" > > > > > > + depends on OF > > > > > > + select LIBFDT > > > > > > + select UCS2_STRING > > > > > > + select EFI_PARAMS_FROM_FDT > > > > > > + select EFI_STUB > > > > > > + select EFI_GENERIC_STUB > > > > > > + default y > > > > > > + help > > > > > > + This option provides support for runtime services provided > > > > > > + by UEFI firmware (such as non-volatile variables, realtime > > > > > > + clock, and platform reset). A UEFI stub is also provided to > > > > > > + allow the kernel to be booted as an EFI application. This > > > > > > + is only useful on systems that have UEFI firmware. > > > > > > + > > > > > > endmenu > > > > > > > > > > > > menu "Power management options" > > > > > > > > > > > > source "kernel/power/Kconfig" > > > > > > +source "drivers/firmware/Kconfig" > > > > > > > > > > > > endmenu > > > > > > diff --git a/arch/riscv/Makefile b/arch/riscv/Makefile > > > > > > index fb6e37db836d..079435804d6d 100644 > > > > > > --- a/arch/riscv/Makefile > > > > > > +++ b/arch/riscv/Makefile > > > > > > @@ -80,6 +80,7 @@ head-y := arch/riscv/kernel/head.o > > > > > > core-y += arch/riscv/ > > > > > > > > > > > > libs-y += arch/riscv/lib/ > > > > > > +core-$(CONFIG_EFI_STUB) += $(objtree)/drivers/firmware/efi/libstub/lib.a > > > > > > > > > > > > PHONY += vdso_install > > > > > > vdso_install: > > > > > > diff --git a/arch/riscv/configs/defconfig b/arch/riscv/configs/defconfig > > > > > > index 4da4886246a4..ae69e12d306a 100644 > > > > > > --- a/arch/riscv/configs/defconfig > > > > > > +++ b/arch/riscv/configs/defconfig > > > > > > @@ -129,3 +129,4 @@ CONFIG_DEBUG_BLOCK_EXT_DEVT=y > > > > > > # CONFIG_RUNTIME_TESTING_MENU is not set > > > > > > CONFIG_MEMTEST=y > > > > > > # CONFIG_SYSFS_SYSCALL is not set > > > > > > +CONFIG_EFI=y > > > > > > diff --git a/arch/riscv/include/asm/efi.h b/arch/riscv/include/asm/efi.h > > > > > > new file mode 100644 > > > > > > index 000000000000..62d7d5eafed8 > > > > > > --- /dev/null > > > > > > +++ b/arch/riscv/include/asm/efi.h > > > > > > @@ -0,0 +1,44 @@ > > > > > > +/* SPDX-License-Identifier: GPL-2.0 */ > > > > > > +/* > > > > > > + * Copyright (C) 2020 Western Digital Corporation or its affiliates. > > > > > > + * Based on arch/arm64/include/asm/efi.h > > > > > > + */ > > > > > > +#ifndef _ASM_EFI_H > > > > > > +#define _ASM_EFI_H > > > > > > + > > > > > > +#include <asm/io.h> > > > > > > +#include <asm/mmu_context.h> > > > > > > +#include <asm/ptrace.h> > > > > > > +#include <asm/tlbflush.h> > > > > > > + > > > > > > +#define VA_BITS_MIN 39 > > > > > > + > > > > > > +/* on RISC-V, the FDT may be located anywhere in system RAM */ > > > > > > +static inline unsigned long efi_get_max_fdt_addr(unsigned long dram_base) > > > > > > +{ > > > > > > + return ULONG_MAX; > > > > > > +} > > > > > > + > > > > > > +/* Load initrd at enough distance from DRAM start */ > > > > > > +static inline unsigned long efi_get_max_initrd_addr(unsigned long dram_base, > > > > > > + unsigned long image_addr) > > > > > > +{ > > > > > > + return dram_base + SZ_256M; > > > > > > +} > > > > > > + > > > > > > +#define efi_bs_call(func, ...) efi_system_table()->boottime->func(__VA_ARGS__) > > > > > > +#define efi_rt_call(func, ...) efi_system_table()->runtime->func(__VA_ARGS__) > > > > > > +#define efi_is_native() (true) > > > > > > + > > > > > > +#define efi_table_attr(inst, attr) (inst->attr) > > > > > > + > > > > > > +#define efi_call_proto(inst, func, ...) inst->func(inst, ##__VA_ARGS__) > > > > > > + > > > > > > +#define alloc_screen_info(x...) (&screen_info) > > > > > > +extern char stext_offset[]; > > > > > > + > > > > > > +static inline void free_screen_info(struct screen_info *si) > > > > > > +{ > > > > > > +} > > > > > > + > > > > > > +#endif /* _ASM_EFI_H */ > > > > > > diff --git a/drivers/firmware/efi/Kconfig b/drivers/firmware/efi/Kconfig > > > > > > index 2a2b2b96a1dc..fcdc789d3f87 100644 > > > > > > --- a/drivers/firmware/efi/Kconfig > > > > > > +++ b/drivers/firmware/efi/Kconfig > > > > > > @@ -111,7 +111,7 @@ config EFI_GENERIC_STUB > > > > > > > > > > > > config EFI_ARMSTUB_DTB_LOADER > > > > > > bool "Enable the DTB loader" > > > > > > - depends on EFI_GENERIC_STUB > > > > > > + depends on EFI_GENERIC_STUB && !RISCV > > > > > > default y > > > > > > help > > > > > > Select this config option to add support for the dtb= command > > > > > > diff --git a/drivers/firmware/efi/libstub/Makefile b/drivers/firmware/efi/libstub/Makefile > > > > > > index 2b4e09bf987c..7d46b70b51f2 100644 > > > > > > --- a/drivers/firmware/efi/libstub/Makefile > > > > > > +++ b/drivers/firmware/efi/libstub/Makefile > > > > > > @@ -22,6 +22,8 @@ cflags-$(CONFIG_ARM64) := $(subst $(CC_FLAGS_FTRACE),,$(KBUILD_CFLAGS)) \ > > > > > > cflags-$(CONFIG_ARM) := $(subst $(CC_FLAGS_FTRACE),,$(KBUILD_CFLAGS)) \ > > > > > > -fno-builtin -fpic \ > > > > > > $(call cc-option,-mno-single-pic-base) > > > > > > +cflags-$(CONFIG_RISCV) := $(subst $(CC_FLAGS_FTRACE),,$(KBUILD_CFLAGS)) \ > > > > > > + -fpic > > > > > > > > > > > > cflags-$(CONFIG_EFI_GENERIC_STUB) += -I$(srctree)/scripts/dtc/libfdt > > > > > > > > > > > > @@ -57,6 +59,7 @@ lib-$(CONFIG_EFI_GENERIC_STUB) += efi-stub.o fdt.o string.o \ > > > > > > lib-$(CONFIG_ARM) += arm32-stub.o > > > > > > lib-$(CONFIG_ARM64) += arm64-stub.o > > > > > > lib-$(CONFIG_X86) += x86-stub.o > > > > > > +lib-$(CONFIG_RISCV) += riscv-stub.o > > > > > > CFLAGS_arm32-stub.o := -DTEXT_OFFSET=$(TEXT_OFFSET) > > > > > > CFLAGS_arm64-stub.o := -DTEXT_OFFSET=$(TEXT_OFFSET) > > > > > > > > > > > > @@ -81,6 +84,10 @@ STUBCOPY_FLAGS-$(CONFIG_ARM64) += --prefix-alloc-sections=.init \ > > > > > > --prefix-symbols=__efistub_ > > > > > > STUBCOPY_RELOC-$(CONFIG_ARM64) := R_AARCH64_ABS > > > > > > > > > > > > +STUBCOPY_FLAGS-$(CONFIG_RISCV) += --prefix-alloc-sections=.init \ > > > > > > + --prefix-symbols=__efistub_ > > > > > > +STUBCOPY_RELOC-$(CONFIG_RISCV) := R_RISCV_HI20 > > > > > > + > > > > > > $(obj)/%.stub.o: $(obj)/%.o FORCE > > > > > > $(call if_changed,stubcopy) > > > > > > > > > > > > diff --git a/drivers/firmware/efi/libstub/riscv-stub.c b/drivers/firmware/efi/libstub/riscv-stub.c > > > > > > new file mode 100644 > > > > > > index 000000000000..69d13e0ebaea > > > > > > --- /dev/null > > > > > > +++ b/drivers/firmware/efi/libstub/riscv-stub.c > > > > > > @@ -0,0 +1,111 @@ > > > > > > +// SPDX-License-Identifier: GPL-2.0 > > > > > > +/* > > > > > > + * Copyright (C) 2013, 2014 Linaro Ltd; <roy.franz@linaro.org> > > > > > > + * Copyright (C) 2020 Western Digital Corporation or its affiliates. > > > > > > + * > > > > > > + * This file implements the EFI boot stub for the RISC-V kernel. > > > > > > + * Adapted from ARM64 version at drivers/firmware/efi/libstub/arm64-stub.c. > > > > > > + */ > > > > > > + > > > > > > +#include <linux/efi.h> > > > > > > +#include <linux/libfdt.h> > > > > > > +#include <linux/libfdt_env.h> > > > > > > +#include <asm/efi.h> > > > > > > +#include <asm/sections.h> > > > > > > + > > > > > > +#include "efistub.h" > > > > > > +/* > > > > > > + * RISCV requires the kernel image to placed TEXT_OFFSET bytes beyond a 2 MB > > > > > > + * aligned base for 64 bit and 4MB for 32 bit. > > > > > > + */ > > > > > > > > Fixed the comment. > > > > > > > > > > +#ifdef CONFIG_64BIT > > > > > > +#define MIN_KIMG_ALIGN SZ_2M > > > > > > +#else > > > > > > +#define MIN_KIMG_ALIGN SZ_4M > > > > > > +#endif > > > > > > + > > > > > > +typedef __attribute__((noreturn)) void (*jump_kernel_func)(unsigned int, > > > > > > + unsigned long); > > > > > > +efi_status_t check_platform_features(void) > > > > > > +{ > > > > > > + return EFI_SUCCESS; > > > > > > +} > > > > > > + > > > > > > +static u32 get_boot_hartid_from_fdt(unsigned long fdt) > > > > > > +{ > > > > > > + int chosen_node, len; > > > > > > + const fdt32_t *prop; > > > > > > + > > > > > > + chosen_node = fdt_path_offset((void *)fdt, "/chosen"); > > > > > > + if (chosen_node < 0) > > > > > > + return U32_MAX; > > > > > > + prop = fdt_getprop((void *)fdt, chosen_node, "boot-hartid", &len); > > > > > > + if (!prop || len != sizeof(u32)) > > > > > > + return U32_MAX; > > > > > > + > > > > > > + return fdt32_to_cpu(*prop); > > > > > > +} > > > > > > + > > > > > > +/* > > > > > > + * Jump to real kernel here with following constraints. > > > > > > + * 1. MMU should be disabled. > > > > > > + * 2. a0 should contain hartid > > > > > > + * 3. a1 should DT address > > > > > > + */ > > > > > > +void __noreturn efi_enter_kernel(unsigned long entrypoint, unsigned long fdt, > > > > > > + unsigned long fdt_size) > > > > > > +{ > > > > > > + unsigned long kernel_entry = entrypoint + (unsigned long)stext_offset; > > > > > > + jump_kernel_func jump_kernel = (jump_kernel_func) kernel_entry; > > > > > > + u32 hartid = get_boot_hartid_from_fdt(fdt); > > > > > > + > > > > > > + if (hartid == U32_MAX) > > > > > > + /* We can not use panic or BUG at this point */ > > > > > > + __asm__ __volatile__ ("ebreak"); > > > > > > + /* Disable MMU */ > > > > > > + csr_write(CSR_SATP, 0); > > > > > > + jump_kernel(hartid, fdt); > > > > > > +} > > > > > > + > > > > > > +efi_status_t handle_kernel_image(unsigned long *image_addr, > > > > > > + unsigned long *image_size, > > > > > > + unsigned long *reserve_addr, > > > > > > + unsigned long *reserve_size, > > > > > > + unsigned long dram_base, > > > > > > + efi_loaded_image_t *image) > > > > > > +{ > > > > > > + efi_status_t status; > > > > > > + unsigned long kernel_size, kernel_memsize = 0; > > > > > > + unsigned long max_alloc_address; > > > > > > + > > > > > > + if (image->image_base != _start) > > > > > > + pr_efi_err("FIRMWARE BUG: efi_loaded_image_t::image_base has bogus value\n"); > > > > > > + > > > > > > > > > > I don't think you need this. > > > > > > > > > > > > > Sure. I will remove it. I guess ARM64 code has the error print for > > > > legacy loader code ? > > > > > > > > > > No, for broken distro versions of GRUB > > > > > > > > > + kernel_size = _edata - _start; > > > > > > + kernel_memsize = kernel_size + (_end - _edata); > > > > > > + max_alloc_address = round_up(dram_base, MIN_KIMG_ALIGN) + > > > > > > + kernel_memsize; > > > > > > + > > > > > > > > > > You said the kernel could be anywhere in memory, as long as it is > > > > > aligned correctly, right? > > > > > > > > Sorry I was wrong about this. RISC-V kernel maps PAGE_OFFSET virtual > > > > address to the > > > > physical address <xyz> where it is booted. That means memory between > > > > dram start and and <xyz> address > > > > will be unusable. > > > > > > > > > > OK > > > > > > > I also realized that the above computing max_address as above also > > > > won't work for the following reason. > > > > efi_allocate_pages_aligned actually ALIGN_DOWN the max_address. Thus, > > > > efi won't find enough > > > > free memory in this case if the max_address is computed from the dram_base. > > > > > > > > Is there an implicit requirement for efi_allocate_pages_aligned or > > > > efi_low_alloc_above should be tried in case of failure? > > > > > > > > > > No not really. What ever works for your particular use case is acceptable to me. > > > > > > > > In that case, you don't need this, you can simply pass ULONG_MAX as > > > > > the max address. > > > > > > > > > As RISC-V should allocate memory as low as possible to avoid memory > > > > wastage, I think the following should work. > > > > > > > > efi_low_alloc_above(*reserve_size, MIN_KIMG_ALIGN, reserve_addr, dram_base); > > > > > > > > If this looks okay to you, efi_low_alloc_above should be moved back to > > > > mem.c from relocate.c. > > > > Should I do it in a separate patch or the original patch should be > > > > modified so that efi_low_alloc_above was never moved to relocate.c > > > > > > > > > > No, please keep efi_low_alloc_above() where it is, but drop the > > > static, and put back the declaration in efistub.h > > > > > > > Alternatively, can you check whether efi_relocate_kernel() already > > does what you need? > > Yeah. efi_relocate_kernel works too. It's just that > efi_relocate_kernel expects a preferred address > which RISC-V doesn't care about. There is a preferred address, no? The base of DRAM? > I can pass ULONG_MAX so that > efi_bs_call will fail and > efi_low_alloc_above will be invoked eventually. > > I am also thinking to put a check in relocate_kernel for preferred > address != ULONG_MAX to avoid > an extra efi_bs_call. The extra call doesn't actually create an issue, > just a minor optimization. > But if that is not acceptable for generic code, that is fine as well. > > Thanks for your suggestions and time. > -- > Regards, > Atish
diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig index f39e326a7a42..eb4f41c8f3ce 100644 --- a/arch/riscv/Kconfig +++ b/arch/riscv/Kconfig @@ -379,10 +379,30 @@ config CMDLINE_FORCE endchoice +config EFI_STUB + bool + +config EFI + bool "UEFI runtime support" + depends on OF + select LIBFDT + select UCS2_STRING + select EFI_PARAMS_FROM_FDT + select EFI_STUB + select EFI_GENERIC_STUB + default y + help + This option provides support for runtime services provided + by UEFI firmware (such as non-volatile variables, realtime + clock, and platform reset). A UEFI stub is also provided to + allow the kernel to be booted as an EFI application. This + is only useful on systems that have UEFI firmware. + endmenu menu "Power management options" source "kernel/power/Kconfig" +source "drivers/firmware/Kconfig" endmenu diff --git a/arch/riscv/Makefile b/arch/riscv/Makefile index fb6e37db836d..079435804d6d 100644 --- a/arch/riscv/Makefile +++ b/arch/riscv/Makefile @@ -80,6 +80,7 @@ head-y := arch/riscv/kernel/head.o core-y += arch/riscv/ libs-y += arch/riscv/lib/ +core-$(CONFIG_EFI_STUB) += $(objtree)/drivers/firmware/efi/libstub/lib.a PHONY += vdso_install vdso_install: diff --git a/arch/riscv/configs/defconfig b/arch/riscv/configs/defconfig index 4da4886246a4..ae69e12d306a 100644 --- a/arch/riscv/configs/defconfig +++ b/arch/riscv/configs/defconfig @@ -129,3 +129,4 @@ CONFIG_DEBUG_BLOCK_EXT_DEVT=y # CONFIG_RUNTIME_TESTING_MENU is not set CONFIG_MEMTEST=y # CONFIG_SYSFS_SYSCALL is not set +CONFIG_EFI=y diff --git a/arch/riscv/include/asm/efi.h b/arch/riscv/include/asm/efi.h new file mode 100644 index 000000000000..62d7d5eafed8 --- /dev/null +++ b/arch/riscv/include/asm/efi.h @@ -0,0 +1,44 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * Copyright (C) 2020 Western Digital Corporation or its affiliates. + * Based on arch/arm64/include/asm/efi.h + */ +#ifndef _ASM_EFI_H +#define _ASM_EFI_H + +#include <asm/io.h> +#include <asm/mmu_context.h> +#include <asm/ptrace.h> +#include <asm/tlbflush.h> + +#define VA_BITS_MIN 39 + +/* on RISC-V, the FDT may be located anywhere in system RAM */ +static inline unsigned long efi_get_max_fdt_addr(unsigned long dram_base) +{ + return ULONG_MAX; +} + +/* Load initrd at enough distance from DRAM start */ +static inline unsigned long efi_get_max_initrd_addr(unsigned long dram_base, + unsigned long image_addr) +{ + return dram_base + SZ_256M; +} + +#define efi_bs_call(func, ...) efi_system_table()->boottime->func(__VA_ARGS__) +#define efi_rt_call(func, ...) efi_system_table()->runtime->func(__VA_ARGS__) +#define efi_is_native() (true) + +#define efi_table_attr(inst, attr) (inst->attr) + +#define efi_call_proto(inst, func, ...) inst->func(inst, ##__VA_ARGS__) + +#define alloc_screen_info(x...) (&screen_info) +extern char stext_offset[]; + +static inline void free_screen_info(struct screen_info *si) +{ +} + +#endif /* _ASM_EFI_H */ diff --git a/drivers/firmware/efi/Kconfig b/drivers/firmware/efi/Kconfig index 2a2b2b96a1dc..fcdc789d3f87 100644 --- a/drivers/firmware/efi/Kconfig +++ b/drivers/firmware/efi/Kconfig @@ -111,7 +111,7 @@ config EFI_GENERIC_STUB config EFI_ARMSTUB_DTB_LOADER bool "Enable the DTB loader" - depends on EFI_GENERIC_STUB + depends on EFI_GENERIC_STUB && !RISCV default y help Select this config option to add support for the dtb= command diff --git a/drivers/firmware/efi/libstub/Makefile b/drivers/firmware/efi/libstub/Makefile index 2b4e09bf987c..7d46b70b51f2 100644 --- a/drivers/firmware/efi/libstub/Makefile +++ b/drivers/firmware/efi/libstub/Makefile @@ -22,6 +22,8 @@ cflags-$(CONFIG_ARM64) := $(subst $(CC_FLAGS_FTRACE),,$(KBUILD_CFLAGS)) \ cflags-$(CONFIG_ARM) := $(subst $(CC_FLAGS_FTRACE),,$(KBUILD_CFLAGS)) \ -fno-builtin -fpic \ $(call cc-option,-mno-single-pic-base) +cflags-$(CONFIG_RISCV) := $(subst $(CC_FLAGS_FTRACE),,$(KBUILD_CFLAGS)) \ + -fpic cflags-$(CONFIG_EFI_GENERIC_STUB) += -I$(srctree)/scripts/dtc/libfdt @@ -57,6 +59,7 @@ lib-$(CONFIG_EFI_GENERIC_STUB) += efi-stub.o fdt.o string.o \ lib-$(CONFIG_ARM) += arm32-stub.o lib-$(CONFIG_ARM64) += arm64-stub.o lib-$(CONFIG_X86) += x86-stub.o +lib-$(CONFIG_RISCV) += riscv-stub.o CFLAGS_arm32-stub.o := -DTEXT_OFFSET=$(TEXT_OFFSET) CFLAGS_arm64-stub.o := -DTEXT_OFFSET=$(TEXT_OFFSET) @@ -81,6 +84,10 @@ STUBCOPY_FLAGS-$(CONFIG_ARM64) += --prefix-alloc-sections=.init \ --prefix-symbols=__efistub_ STUBCOPY_RELOC-$(CONFIG_ARM64) := R_AARCH64_ABS +STUBCOPY_FLAGS-$(CONFIG_RISCV) += --prefix-alloc-sections=.init \ + --prefix-symbols=__efistub_ +STUBCOPY_RELOC-$(CONFIG_RISCV) := R_RISCV_HI20 + $(obj)/%.stub.o: $(obj)/%.o FORCE $(call if_changed,stubcopy) diff --git a/drivers/firmware/efi/libstub/riscv-stub.c b/drivers/firmware/efi/libstub/riscv-stub.c new file mode 100644 index 000000000000..69d13e0ebaea --- /dev/null +++ b/drivers/firmware/efi/libstub/riscv-stub.c @@ -0,0 +1,111 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright (C) 2013, 2014 Linaro Ltd; <roy.franz@linaro.org> + * Copyright (C) 2020 Western Digital Corporation or its affiliates. + * + * This file implements the EFI boot stub for the RISC-V kernel. + * Adapted from ARM64 version at drivers/firmware/efi/libstub/arm64-stub.c. + */ + +#include <linux/efi.h> +#include <linux/libfdt.h> +#include <linux/libfdt_env.h> +#include <asm/efi.h> +#include <asm/sections.h> + +#include "efistub.h" +/* + * RISCV requires the kernel image to placed TEXT_OFFSET bytes beyond a 2 MB + * aligned base for 64 bit and 4MB for 32 bit. + */ +#ifdef CONFIG_64BIT +#define MIN_KIMG_ALIGN SZ_2M +#else +#define MIN_KIMG_ALIGN SZ_4M +#endif + +typedef __attribute__((noreturn)) void (*jump_kernel_func)(unsigned int, + unsigned long); +efi_status_t check_platform_features(void) +{ + return EFI_SUCCESS; +} + +static u32 get_boot_hartid_from_fdt(unsigned long fdt) +{ + int chosen_node, len; + const fdt32_t *prop; + + chosen_node = fdt_path_offset((void *)fdt, "/chosen"); + if (chosen_node < 0) + return U32_MAX; + prop = fdt_getprop((void *)fdt, chosen_node, "boot-hartid", &len); + if (!prop || len != sizeof(u32)) + return U32_MAX; + + return fdt32_to_cpu(*prop); +} + +/* + * Jump to real kernel here with following constraints. + * 1. MMU should be disabled. + * 2. a0 should contain hartid + * 3. a1 should DT address + */ +void __noreturn efi_enter_kernel(unsigned long entrypoint, unsigned long fdt, + unsigned long fdt_size) +{ + unsigned long kernel_entry = entrypoint + (unsigned long)stext_offset; + jump_kernel_func jump_kernel = (jump_kernel_func) kernel_entry; + u32 hartid = get_boot_hartid_from_fdt(fdt); + + if (hartid == U32_MAX) + /* We can not use panic or BUG at this point */ + __asm__ __volatile__ ("ebreak"); + /* Disable MMU */ + csr_write(CSR_SATP, 0); + jump_kernel(hartid, fdt); +} + +efi_status_t handle_kernel_image(unsigned long *image_addr, + unsigned long *image_size, + unsigned long *reserve_addr, + unsigned long *reserve_size, + unsigned long dram_base, + efi_loaded_image_t *image) +{ + efi_status_t status; + unsigned long kernel_size, kernel_memsize = 0; + unsigned long max_alloc_address; + + if (image->image_base != _start) + pr_efi_err("FIRMWARE BUG: efi_loaded_image_t::image_base has bogus value\n"); + + kernel_size = _edata - _start; + kernel_memsize = kernel_size + (_end - _edata); + max_alloc_address = round_up(dram_base, MIN_KIMG_ALIGN) + + kernel_memsize; + + if (IS_ALIGNED((u64)_start, MIN_KIMG_ALIGN)) { + /* + * Just execute from wherever we were loaded by the + * UEFI PE/COFF loader if the alignment is suitable. + */ + *image_addr = (u64)_start; + *reserve_size = 0; + return EFI_SUCCESS; + } + status = efi_allocate_pages_aligned(*reserve_size, reserve_addr, + max_alloc_address, MIN_KIMG_ALIGN); + + if (status != EFI_SUCCESS) { + pr_efi_err("Failed to relocate kernel\n"); + *reserve_size = 0; + return status; + } + *image_addr = *reserve_addr; + + memcpy((void *)*image_addr, _start, kernel_size); + + return EFI_SUCCESS; +}
Add a RISC-V architecture specific stub code that actually copies the actual kernel image to a valid address and jump to it after boot services are terminated. Enable UEFI related kernel configs as well for RISC-V. Signed-off-by: Atish Patra <atish.patra@wdc.com> --- arch/riscv/Kconfig | 20 ++++ arch/riscv/Makefile | 1 + arch/riscv/configs/defconfig | 1 + arch/riscv/include/asm/efi.h | 44 +++++++++ drivers/firmware/efi/Kconfig | 2 +- drivers/firmware/efi/libstub/Makefile | 7 ++ drivers/firmware/efi/libstub/riscv-stub.c | 111 ++++++++++++++++++++++ 7 files changed, 185 insertions(+), 1 deletion(-) create mode 100644 arch/riscv/include/asm/efi.h create mode 100644 drivers/firmware/efi/libstub/riscv-stub.c