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[v5,2/7] MIPS: JZ4780: Introduce SMP support.

Message ID 1581792932-108032-4-git-send-email-zhouyanjie@wanyeetech.com (mailing list archive)
State Not Applicable, archived
Headers show
Series [v5,1/7] clk: JZ4780: Add function for enable the second core. | expand

Commit Message

Zhou Yanjie Feb. 15, 2020, 6:55 p.m. UTC
Forward port smp support from kernel 3.18.3 of CI20_linux
to upstream kernel 5.6.

Tested-by: H. Nikolaus Schaller <hns@goldelico.com>
Tested-by: Paul Boddie <paul@boddie.org.uk>
Signed-off-by: 周琰杰 (Zhou Yanjie) <zhouyanjie@wanyeetech.com>
Reviewed-by: Jiaxun Yang <jiaxun.yang@flygoat.com>
---

Notes:
    v1->v2:
    1.Remove unnecessary "plat_irq_dispatch(void)" in irq-ingenic.c.
    2.Add a timeout check for "jz4780_boot_secondary()" to avoid a dead loop.
    3.Replace hard code in smp.c with macro.
    
    v2->v3:
    1.Remove unnecessary "extern void (*r4k_blast_dcache)(void)" in smp.c.
    2.Use "for_each_of_cpu_node" instead "for_each_compatible_node" in smp.c.
    3.Use "of_cpu_node_to_id" instead "of_property_read_u32_index" in smp.c.
    4.Move LCR related operations to jz4780-cgu.c.
    
    v3->v4:
    Rebase on top of kernel 5.6-rc1.
    
    v4->v5:
    1.Splitting changes involving "jz4780-cgu.c" into separate commit.
    2.Use "request_irq()" replace "setup_irq()".

 arch/mips/include/asm/mach-jz4740/jz4780-smp.h |  91 ++++++++
 arch/mips/jz4740/Kconfig                       |   3 +
 arch/mips/jz4740/Makefile                      |   5 +
 arch/mips/jz4740/prom.c                        |   4 +
 arch/mips/jz4740/smp-entry.S                   |  57 +++++
 arch/mips/jz4740/smp.c                         | 283 +++++++++++++++++++++++++
 arch/mips/kernel/idle.c                        |  14 +-
 7 files changed, 456 insertions(+), 1 deletion(-)
 create mode 100644 arch/mips/include/asm/mach-jz4740/jz4780-smp.h
 create mode 100644 arch/mips/jz4740/smp-entry.S
 create mode 100644 arch/mips/jz4740/smp.c

Comments

Paul Cercueil Feb. 16, 2020, 2:59 p.m. UTC | #1
Hi Zhou,


Le dim., févr. 16, 2020 at 02:55, 周琰杰 (Zhou Yanjie) 
<zhouyanjie@wanyeetech.com> a écrit :
> Forward port smp support from kernel 3.18.3 of CI20_linux
> to upstream kernel 5.6.
> 
> Tested-by: H. Nikolaus Schaller <hns@goldelico.com>
> Tested-by: Paul Boddie <paul@boddie.org.uk>
> Signed-off-by: 周琰杰 (Zhou Yanjie) <zhouyanjie@wanyeetech.com>
> Reviewed-by: Jiaxun Yang <jiaxun.yang@flygoat.com>
> ---
> 
> Notes:
>     v1->v2:
>     1.Remove unnecessary "plat_irq_dispatch(void)" in irq-ingenic.c.
>     2.Add a timeout check for "jz4780_boot_secondary()" to avoid a 
> dead loop.
>     3.Replace hard code in smp.c with macro.
> 
>     v2->v3:
>     1.Remove unnecessary "extern void (*r4k_blast_dcache)(void)" in 
> smp.c.
>     2.Use "for_each_of_cpu_node" instead "for_each_compatible_node" 
> in smp.c.
>     3.Use "of_cpu_node_to_id" instead "of_property_read_u32_index" in 
> smp.c.
>     4.Move LCR related operations to jz4780-cgu.c.
> 
>     v3->v4:
>     Rebase on top of kernel 5.6-rc1.
> 
>     v4->v5:
>     1.Splitting changes involving "jz4780-cgu.c" into separate commit.
>     2.Use "request_irq()" replace "setup_irq()".
> 
>  arch/mips/include/asm/mach-jz4740/jz4780-smp.h |  91 ++++++++
>  arch/mips/jz4740/Kconfig                       |   3 +
>  arch/mips/jz4740/Makefile                      |   5 +
>  arch/mips/jz4740/prom.c                        |   4 +
>  arch/mips/jz4740/smp-entry.S                   |  57 +++++
>  arch/mips/jz4740/smp.c                         | 283 
> +++++++++++++++++++++++++
>  arch/mips/kernel/idle.c                        |  14 +-
>  7 files changed, 456 insertions(+), 1 deletion(-)
>  create mode 100644 arch/mips/include/asm/mach-jz4740/jz4780-smp.h
>  create mode 100644 arch/mips/jz4740/smp-entry.S
>  create mode 100644 arch/mips/jz4740/smp.c
> 
> diff --git a/arch/mips/include/asm/mach-jz4740/jz4780-smp.h 
> b/arch/mips/include/asm/mach-jz4740/jz4780-smp.h
> new file mode 100644
> index 00000000..3f592ce
> --- /dev/null
> +++ b/arch/mips/include/asm/mach-jz4740/jz4780-smp.h
> @@ -0,0 +1,91 @@
> +/* SPDX-License-Identifier: GPL-2.0-or-later */
> +/*
> + *  Copyright (C) 2013, Paul Burton <paul.burton@imgtec.com>
> + *  JZ4780 SMP definitions
> + */
> +
> +#ifndef __MIPS_ASM_MACH_JZ4740_JZ4780_SMP_H__
> +#define __MIPS_ASM_MACH_JZ4740_JZ4780_SMP_H__
> +
> +#define read_c0_corectrl()		__read_32bit_c0_register($12, 2)
> +#define write_c0_corectrl(val)		__write_32bit_c0_register($12, 2, 
> val)
> +
> +#define read_c0_corestatus()		__read_32bit_c0_register($12, 3)
> +#define write_c0_corestatus(val)	__write_32bit_c0_register($12, 3, 
> val)
> +
> +#define read_c0_reim()			__read_32bit_c0_register($12, 4)
> +#define write_c0_reim(val)		__write_32bit_c0_register($12, 4, val)
> +
> +#define read_c0_mailbox0()		__read_32bit_c0_register($20, 0)
> +#define write_c0_mailbox0(val)		__write_32bit_c0_register($20, 0, 
> val)
> +
> +#define read_c0_mailbox1()		__read_32bit_c0_register($20, 1)
> +#define write_c0_mailbox1(val)		__write_32bit_c0_register($20, 1, 
> val)
> +
> +#define smp_clr_pending(mask) do {		\
> +		unsigned int stat;		\
> +		stat = read_c0_corestatus();	\
> +		stat &= ~((mask) & 0xff);	\
> +		write_c0_corestatus(stat);	\
> +	} while (0)
> +
> +/*
> + * Core Control register
> + */
> +#define CORECTRL_SLEEP1M_SHIFT	17
> +#define CORECTRL_SLEEP1M	(_ULCAST_(0x1) << CORECTRL_SLEEP1M_SHIFT)
> +#define CORECTRL_SLEEP0M_SHIFT	16
> +#define CORECTRL_SLEEP0M	(_ULCAST_(0x1) << CORECTRL_SLEEP0M_SHIFT)
> +#define CORECTRL_RPC1_SHIFT	9
> +#define CORECTRL_RPC1		(_ULCAST_(0x1) << CORECTRL_RPC1_SHIFT)
> +#define CORECTRL_RPC0_SHIFT	8
> +#define CORECTRL_RPC0		(_ULCAST_(0x1) << CORECTRL_RPC0_SHIFT)
> +#define CORECTRL_SWRST1_SHIFT	1
> +#define CORECTRL_SWRST1		(_ULCAST_(0x1) << CORECTRL_SWRST1_SHIFT)
> +#define CORECTRL_SWRST0_SHIFT	0
> +#define CORECTRL_SWRST0		(_ULCAST_(0x1) << CORECTRL_SWRST0_SHIFT)
> +
> +/*
> + * Core Status register
> + */
> +#define CORESTATUS_SLEEP1_SHIFT	17
> +#define CORESTATUS_SLEEP1	(_ULCAST_(0x1) << CORESTATUS_SLEEP1_SHIFT)
> +#define CORESTATUS_SLEEP0_SHIFT	16
> +#define CORESTATUS_SLEEP0	(_ULCAST_(0x1) << CORESTATUS_SLEEP0_SHIFT)
> +#define CORESTATUS_IRQ1P_SHIFT	9
> +#define CORESTATUS_IRQ1P	(_ULCAST_(0x1) << CORESTATUS_IRQ1P_SHIFT)
> +#define CORESTATUS_IRQ0P_SHIFT	8
> +#define CORESTATUS_IRQ0P	(_ULCAST_(0x1) << CORESTATUS_IRQ8P_SHIFT)
> +#define CORESTATUS_MIRQ1P_SHIFT	1
> +#define CORESTATUS_MIRQ1P	(_ULCAST_(0x1) << CORESTATUS_MIRQ1P_SHIFT)
> +#define CORESTATUS_MIRQ0P_SHIFT	0
> +#define CORESTATUS_MIRQ0P	(_ULCAST_(0x1) << CORESTATUS_MIRQ0P_SHIFT)
> +
> +/*
> + * Reset Entry & IRQ Mask register
> + */
> +#define REIM_ENTRY_SHIFT	16
> +#define REIM_ENTRY		(_ULCAST_(0xffff) << REIM_ENTRY_SHIFT)
> +#define REIM_IRQ1M_SHIFT	9
> +#define REIM_IRQ1M		(_ULCAST_(0x1) << REIM_IRQ1M_SHIFT)
> +#define REIM_IRQ0M_SHIFT	8
> +#define REIM_IRQ0M		(_ULCAST_(0x1) << REIM_IRQ0M_SHIFT)
> +#define REIM_MBOXIRQ1M_SHIFT	1
> +#define REIM_MBOXIRQ1M		(_ULCAST_(0x1) << REIM_MBOXIRQ1M_SHIFT)
> +#define REIM_MBOXIRQ0M_SHIFT	0
> +#define REIM_MBOXIRQ0M		(_ULCAST_(0x1) << REIM_MBOXIRQ0M_SHIFT)
> +
> +#ifdef CONFIG_SMP
> +
> +extern void jz4780_smp_wait_irqoff(void);
> +
> +extern void jz4780_smp_init(void);
> +extern void jz4780_secondary_cpu_entry(void);
> +
> +#else /* !CONFIG_SMP */
> +
> +static inline void jz4780_smp_init(void) { }
> +
> +#endif /* !CONFIG_SMP */
> +
> +#endif /* __MIPS_ASM_MACH_JZ4740_JZ4780_SMP_H__ */
> diff --git a/arch/mips/jz4740/Kconfig b/arch/mips/jz4740/Kconfig
> index 412d2fa..0239597 100644
> --- a/arch/mips/jz4740/Kconfig
> +++ b/arch/mips/jz4740/Kconfig
> @@ -34,9 +34,12 @@ config MACH_JZ4770
> 
>  config MACH_JZ4780
>  	bool
> +	select GENERIC_CLOCKEVENTS_BROADCAST if SMP
>  	select MIPS_CPU_SCACHE
> +	select NR_CPUS_DEFAULT_2
>  	select SYS_HAS_CPU_MIPS32_R2
>  	select SYS_SUPPORTS_HIGHMEM
> +	select SYS_SUPPORTS_SMP
> 
>  config MACH_X1000
>  	bool
> diff --git a/arch/mips/jz4740/Makefile b/arch/mips/jz4740/Makefile
> index 6de14c0..0a0f024 100644
> --- a/arch/mips/jz4740/Makefile
> +++ b/arch/mips/jz4740/Makefile
> @@ -12,3 +12,8 @@ CFLAGS_setup.o = 
> -I$(src)/../../../scripts/dtc/libfdt
>  # PM support
> 
>  obj-$(CONFIG_PM) += pm.o
> +
> +# SMP support
> +
> +obj-$(CONFIG_SMP) += smp.o
> +obj-$(CONFIG_SMP) += smp-entry.o
> diff --git a/arch/mips/jz4740/prom.c b/arch/mips/jz4740/prom.c
> index ff4555c..a79159e 100644
> --- a/arch/mips/jz4740/prom.c
> +++ b/arch/mips/jz4740/prom.c
> @@ -8,10 +8,14 @@
> 
>  #include <asm/bootinfo.h>
>  #include <asm/fw/fw.h>
> +#include <asm/mach-jz4740/jz4780-smp.h>
> 
>  void __init prom_init(void)
>  {
>  	fw_init_cmdline();
> +#if defined(CONFIG_MACH_JZ4780) && defined(CONFIG_SMP)
> +	jz4780_smp_init();
> +#endif

You should not check for defined(CONFIG_MACH_JZ4780), because that 
means you cannot have a kernel that works on multiple SoCs at the same 
time. Instead, check the value of "mips_machtype".

-Paul

>  }
> 
>  void __init prom_free_prom_memory(void)
> diff --git a/arch/mips/jz4740/smp-entry.S 
> b/arch/mips/jz4740/smp-entry.S
> new file mode 100644
> index 00000000..20049a3
> --- /dev/null
> +++ b/arch/mips/jz4740/smp-entry.S
> @@ -0,0 +1,57 @@
> +/* SPDX-License-Identifier: GPL-2.0-or-later */
> +/*
> + *  Copyright (C) 2013, Paul Burton <paul.burton@imgtec.com>
> + *  JZ4780 SMP entry point
> + */
> +
> +#include <asm/addrspace.h>
> +#include <asm/asm.h>
> +#include <asm/asmmacro.h>
> +#include <asm/cacheops.h>
> +#include <asm/mipsregs.h>
> +
> +#define CACHE_SIZE (32 * 1024)
> +#define CACHE_LINESIZE 32
> +
> +.extern jz4780_cpu_entry_sp
> +.extern jz4780_cpu_entry_gp
> +
> +.section .text.smp-entry
> +.balign 0x10000
> +.set noreorder
> +LEAF(jz4780_secondary_cpu_entry)
> +	mtc0	zero, CP0_CAUSE
> +
> +	li	t0, ST0_CU0
> +	mtc0	t0, CP0_STATUS
> +
> +	/* cache setup */
> +	li	t0, KSEG0
> +	ori	t1, t0, CACHE_SIZE
> +	mtc0	zero, CP0_TAGLO, 0
> +1:	cache	Index_Store_Tag_I, 0(t0)
> +	cache	Index_Store_Tag_D, 0(t0)
> +	bne	t0, t1, 1b
> +	 addiu	t0, t0, CACHE_LINESIZE
> +
> +	/* kseg0 cache attribute */
> +	mfc0	t0, CP0_CONFIG, 0
> +	ori	t0, t0, CONF_CM_CACHABLE_NONCOHERENT
> +	mtc0	t0, CP0_CONFIG, 0
> +
> +	/* pagemask */
> +	mtc0	zero, CP0_PAGEMASK, 0
> +
> +	/* retrieve sp */
> +	la	t0, jz4780_cpu_entry_sp
> +	lw	sp, 0(t0)
> +
> +	/* retrieve gp */
> +	la	t0, jz4780_cpu_entry_gp
> +	lw	gp, 0(t0)
> +
> +	/* jump to the kernel in kseg0 */
> +	la	t0, smp_bootstrap
> +	jr	t0
> +	 nop
> +	END(jz4780_secondary_cpu_entry)
> diff --git a/arch/mips/jz4740/smp.c b/arch/mips/jz4740/smp.c
> new file mode 100644
> index 00000000..826fd0f
> --- /dev/null
> +++ b/arch/mips/jz4740/smp.c
> @@ -0,0 +1,283 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/*
> + *  Copyright (C) 2013, Paul Burton <paul.burton@imgtec.com>
> + *  JZ4780 SMP
> + */
> +
> +#include <linux/clk.h>
> +#include <linux/delay.h>
> +#include <linux/interrupt.h>
> +#include <linux/of.h>
> +#include <linux/sched.h>
> +#include <linux/sched/task_stack.h>
> +#include <linux/smp.h>
> +#include <linux/tick.h>
> +#include <asm/mach-jz4740/jz4780-smp.h>
> +#include <asm/r4kcache.h>
> +#include <asm/smp-ops.h>
> +
> +static struct clk *cpu_clock_gates[CONFIG_NR_CPUS] = { NULL };
> +
> +u32 jz4780_cpu_entry_sp;
> +u32 jz4780_cpu_entry_gp;
> +
> +static struct cpumask cpu_running;
> +
> +static DEFINE_SPINLOCK(smp_lock);
> +
> +/*
> + * The Ingenic jz4780 SMP variant has to write back dirty cache 
> lines before
> + * executing wait. The CPU & cache clock will be gated until we 
> return from
> + * the wait, and if another core attempts to access data from our 
> data cache
> + * during this time then it will lock up.
> + */
> +void jz4780_smp_wait_irqoff(void)
> +{
> +	unsigned long pending = read_c0_cause() & read_c0_status() & 
> CAUSEF_IP;
> +
> +	/*
> +	 * Going to idle has a significant overhead due to the cache flush 
> so
> +	 * try to avoid it if we'll immediately be woken again due to an 
> IRQ.
> +	 */
> +	if (!need_resched() && !pending) {
> +		r4k_blast_dcache();
> +
> +		__asm__(
> +		"	.set push	\n"
> +		"	.set mips3	\n"
> +		"	sync		\n"
> +		"	wait		\n"
> +		"	.set pop	\n");
> +	}
> +
> +	local_irq_enable();
> +}
> +
> +static irqreturn_t mbox_handler(int irq, void *dev_id)
> +{
> +	int cpu = smp_processor_id();
> +	u32 action, status;
> +
> +	spin_lock(&smp_lock);
> +
> +	switch (cpu) {
> +	case 0:
> +		action = read_c0_mailbox0();
> +		write_c0_mailbox0(0);
> +		break;
> +	case 1:
> +		action = read_c0_mailbox1();
> +		write_c0_mailbox1(0);
> +		break;
> +	default:
> +		panic("unhandled cpu %d!", cpu);
> +	}
> +
> +	/* clear pending mailbox interrupt */
> +	status = read_c0_corestatus();
> +	status &= ~(CORESTATUS_MIRQ0P << cpu);
> +	write_c0_corestatus(status);
> +
> +	spin_unlock(&smp_lock);
> +
> +	if (action & SMP_RESCHEDULE_YOURSELF)
> +		scheduler_ipi();
> +	if (action & SMP_CALL_FUNCTION)
> +		generic_smp_call_function_interrupt();
> +
> +	return IRQ_HANDLED;
> +}
> +
> +static void jz4780_smp_setup(void)
> +{
> +	u32 addr, reim;
> +	int cpu;
> +
> +	reim = read_c0_reim();
> +
> +	for (cpu = 0; cpu < NR_CPUS; cpu++) {
> +		__cpu_number_map[cpu] = cpu;
> +		__cpu_logical_map[cpu] = cpu;
> +		set_cpu_possible(cpu, true);
> +	}
> +
> +	/* mask mailbox interrupts for this core */
> +	reim &= ~REIM_MBOXIRQ0M;
> +	write_c0_reim(reim);
> +
> +	/* clear mailboxes & pending mailbox IRQs */
> +	write_c0_mailbox0(0);
> +	write_c0_mailbox1(0);
> +	write_c0_corestatus(0);
> +
> +	/* set reset entry point */
> +	addr = KSEG1ADDR((u32)&jz4780_secondary_cpu_entry);
> +	WARN_ON(addr & ~REIM_ENTRY);
> +	reim &= ~REIM_ENTRY;
> +	reim |= addr & REIM_ENTRY;
> +
> +	/* unmask mailbox interrupts for this core */
> +	reim |= REIM_MBOXIRQ0M;
> +	write_c0_reim(reim);
> +	set_c0_status(STATUSF_IP3);
> +	irq_enable_hazard();
> +
> +	cpumask_set_cpu(cpu, &cpu_running);
> +}
> +
> +static void jz4780_smp_prepare_cpus(unsigned int max_cpus)
> +{
> +	struct device_node *cpu_node;
> +	unsigned cpu, ctrl;
> +	int err;
> +
> +	/* setup the mailbox IRQ */
> +	err = request_irq(MIPS_CPU_IRQ_BASE + 3, mbox_handler,
> +				IRQF_PERCPU | IRQF_NO_THREAD, "core mailbox", NULL);
> +	if (err)
> +		pr_err("request_irq() on core mailbox failed\n");
> +
> +	init_cpu_present(cpu_possible_mask);
> +
> +	ctrl = read_c0_corectrl();
> +
> +	for (cpu = 0; cpu < max_cpus; cpu++) {
> +		/* use reset entry point from REIM register */
> +		ctrl |= CORECTRL_RPC0 << cpu;
> +	}
> +
> +	for_each_of_cpu_node(cpu_node) {
> +		cpu = of_cpu_node_to_id(cpu_node);
> +		if (cpu < 0) {
> +			pr_err("Failed to read index of %s\n",
> +			       cpu_node->full_name);
> +			continue;
> +		}
> +
> +		cpu_clock_gates[cpu] = of_clk_get(cpu_node, 0);
> +		if (IS_ERR(cpu_clock_gates[cpu])) {
> +			cpu_clock_gates[cpu] = NULL;
> +			continue;
> +		}
> +
> +		err = clk_prepare(cpu_clock_gates[cpu]);
> +		if (err)
> +			pr_err("Failed to prepare CPU clock gate\n");
> +	}
> +
> +	write_c0_corectrl(ctrl);
> +}
> +
> +static int jz4780_boot_secondary(int cpu, struct task_struct *idle)
> +{
> +	unsigned long flags;
> +	u32 ctrl;
> +
> +	spin_lock_irqsave(&smp_lock, flags);
> +
> +	/* ensure the core is in reset */
> +	ctrl = read_c0_corectrl();
> +	ctrl |= CORECTRL_SWRST0 << cpu;
> +	write_c0_corectrl(ctrl);
> +
> +	/* ungate core clock */
> +	if (cpu_clock_gates[cpu])
> +		clk_enable(cpu_clock_gates[cpu]);
> +
> +	/* set entry sp/gp register values */
> +	jz4780_cpu_entry_sp = __KSTK_TOS(idle);
> +	jz4780_cpu_entry_gp = (u32)task_thread_info(idle);
> +	smp_wmb();
> +
> +	/* take the core out of reset */
> +	ctrl &= ~(CORECTRL_SWRST0 << cpu);
> +	write_c0_corectrl(ctrl);
> +
> +	cpumask_set_cpu(cpu, &cpu_running);
> +
> +	spin_unlock_irqrestore(&smp_lock, flags);
> +
> +	return 0;
> +}
> +
> +static void jz4780_init_secondary(void)
> +{
> +}
> +
> +static void jz4780_smp_finish(void)
> +{
> +	u32 reim;
> +
> +	spin_lock(&smp_lock);
> +
> +	/* unmask mailbox interrupts for this core */
> +	reim = read_c0_reim();
> +	reim |= REIM_MBOXIRQ0M << smp_processor_id();
> +	write_c0_reim(reim);
> +
> +	spin_unlock(&smp_lock);
> +
> +	/* unmask interrupts for this core */
> +	change_c0_status(ST0_IM, STATUSF_IP3 | STATUSF_IP2 |
> +			 STATUSF_IP1 | STATUSF_IP0);
> +	irq_enable_hazard();
> +
> +	/* force broadcast timer */
> +	tick_broadcast_force();
> +}
> +
> +static void jz4780_send_ipi_single_locked(int cpu, unsigned int 
> action)
> +{
> +	u32 mbox;
> +
> +	switch (cpu) {
> +	case 0:
> +		mbox = read_c0_mailbox0();
> +		write_c0_mailbox0(mbox | action);
> +		break;
> +	case 1:
> +		mbox = read_c0_mailbox1();
> +		write_c0_mailbox1(mbox | action);
> +		break;
> +	default:
> +		panic("unhandled cpu %d!", cpu);
> +	}
> +}
> +
> +static void jz4780_send_ipi_single(int cpu, unsigned int action)
> +{
> +	unsigned long flags;
> +
> +	spin_lock_irqsave(&smp_lock, flags);
> +	jz4780_send_ipi_single_locked(cpu, action);
> +	spin_unlock_irqrestore(&smp_lock, flags);
> +}
> +
> +static void jz4780_send_ipi_mask(const struct cpumask *mask,
> +				 unsigned int action)
> +{
> +	unsigned long flags;
> +	int cpu;
> +
> +	spin_lock_irqsave(&smp_lock, flags);
> +
> +	for_each_cpu(cpu, mask)
> +		jz4780_send_ipi_single_locked(cpu, action);
> +
> +	spin_unlock_irqrestore(&smp_lock, flags);
> +}
> +
> +static struct plat_smp_ops jz4780_smp_ops = {
> +	.send_ipi_single = jz4780_send_ipi_single,
> +	.send_ipi_mask = jz4780_send_ipi_mask,
> +	.init_secondary = jz4780_init_secondary,
> +	.smp_finish = jz4780_smp_finish,
> +	.boot_secondary = jz4780_boot_secondary,
> +	.smp_setup = jz4780_smp_setup,
> +	.prepare_cpus = jz4780_smp_prepare_cpus,
> +};
> +
> +void jz4780_smp_init(void)
> +{
> +	register_smp_ops(&jz4780_smp_ops);
> +}
> diff --git a/arch/mips/kernel/idle.c b/arch/mips/kernel/idle.c
> index 37f8e78..a406de3 100644
> --- a/arch/mips/kernel/idle.c
> +++ b/arch/mips/kernel/idle.c
> @@ -19,6 +19,10 @@
>  #include <asm/idle.h>
>  #include <asm/mipsregs.h>
> 
> +#ifdef CONFIG_MACH_JZ4780
> +# include <asm/mach-jz4740/jz4780-smp.h>
> +#endif
> +
>  /*
>   * Not all of the MIPS CPUs have the "wait" instruction available. 
> Moreover,
>   * the implementation of the "wait" feature differs between CPU 
> families. This
> @@ -172,7 +176,6 @@ void __init check_wait(void)
>  	case CPU_CAVIUM_OCTEON_PLUS:
>  	case CPU_CAVIUM_OCTEON2:
>  	case CPU_CAVIUM_OCTEON3:
> -	case CPU_XBURST:
>  	case CPU_LOONGSON32:
>  	case CPU_XLR:
>  	case CPU_XLP:
> @@ -246,6 +249,15 @@ void __init check_wait(void)
>  		   cpu_wait = r4k_wait;
>  		 */
>  		break;
> +	case CPU_XBURST:
> +#if defined(CONFIG_MACH_JZ4780) && defined(CONFIG_SMP)
> +		if (NR_CPUS > 1)
> +			cpu_wait = jz4780_smp_wait_irqoff;
> +		else
> +			cpu_wait = r4k_wait;
> +#else
> +		cpu_wait = r4k_wait;
> +#endif
>  	default:
>  		break;
>  	}
> --
> 2.7.4
>
Zhou Yanjie Feb. 19, 2020, 7:57 a.m. UTC | #2
Hi Paul,

On 2020年02月16日 22:59, Paul Cercueil wrote:
> Hi Zhou,
>
>
> Le dim., févr. 16, 2020 at 02:55, 周琰杰 (Zhou Yanjie) 
> <zhouyanjie@wanyeetech.com> a écrit :
>> Forward port smp support from kernel 3.18.3 of CI20_linux
>> to upstream kernel 5.6.
>>
>> Tested-by: H. Nikolaus Schaller <hns@goldelico.com>
>> Tested-by: Paul Boddie <paul@boddie.org.uk>
>> Signed-off-by: 周琰杰 (Zhou Yanjie) <zhouyanjie@wanyeetech.com>
>> Reviewed-by: Jiaxun Yang <jiaxun.yang@flygoat.com>
>> ---
>>
>> Notes:
>>     v1->v2:
>>     1.Remove unnecessary "plat_irq_dispatch(void)" in irq-ingenic.c.
>>     2.Add a timeout check for "jz4780_boot_secondary()" to avoid a 
>> dead loop.
>>     3.Replace hard code in smp.c with macro.
>>
>>     v2->v3:
>>     1.Remove unnecessary "extern void (*r4k_blast_dcache)(void)" in 
>> smp.c.
>>     2.Use "for_each_of_cpu_node" instead "for_each_compatible_node" 
>> in smp.c.
>>     3.Use "of_cpu_node_to_id" instead "of_property_read_u32_index" in 
>> smp.c.
>>     4.Move LCR related operations to jz4780-cgu.c.
>>
>>     v3->v4:
>>     Rebase on top of kernel 5.6-rc1.
>>
>>     v4->v5:
>>     1.Splitting changes involving "jz4780-cgu.c" into separate commit.
>>     2.Use "request_irq()" replace "setup_irq()".
>>
>>  arch/mips/include/asm/mach-jz4740/jz4780-smp.h |  91 ++++++++
>>  arch/mips/jz4740/Kconfig                       |   3 +
>>  arch/mips/jz4740/Makefile                      |   5 +
>>  arch/mips/jz4740/prom.c                        |   4 +
>>  arch/mips/jz4740/smp-entry.S                   |  57 +++++
>>  arch/mips/jz4740/smp.c                         | 283 
>> +++++++++++++++++++++++++
>>  arch/mips/kernel/idle.c                        |  14 +-
>>  7 files changed, 456 insertions(+), 1 deletion(-)
>>  create mode 100644 arch/mips/include/asm/mach-jz4740/jz4780-smp.h
>>  create mode 100644 arch/mips/jz4740/smp-entry.S
>>  create mode 100644 arch/mips/jz4740/smp.c
>>
>> diff --git a/arch/mips/include/asm/mach-jz4740/jz4780-smp.h 
>> b/arch/mips/include/asm/mach-jz4740/jz4780-smp.h
>> new file mode 100644
>> index 00000000..3f592ce
>> --- /dev/null
>> +++ b/arch/mips/include/asm/mach-jz4740/jz4780-smp.h
>> @@ -0,0 +1,91 @@
>> +/* SPDX-License-Identifier: GPL-2.0-or-later */
>> +/*
>> + *  Copyright (C) 2013, Paul Burton <paul.burton@imgtec.com>
>> + *  JZ4780 SMP definitions
>> + */
>> +
>> +#ifndef __MIPS_ASM_MACH_JZ4740_JZ4780_SMP_H__
>> +#define __MIPS_ASM_MACH_JZ4740_JZ4780_SMP_H__
>> +
>> +#define read_c0_corectrl()        __read_32bit_c0_register($12, 2)
>> +#define write_c0_corectrl(val) __write_32bit_c0_register($12, 2, val)
>> +
>> +#define read_c0_corestatus() __read_32bit_c0_register($12, 3)
>> +#define write_c0_corestatus(val) __write_32bit_c0_register($12, 3, val)
>> +
>> +#define read_c0_reim()            __read_32bit_c0_register($12, 4)
>> +#define write_c0_reim(val) __write_32bit_c0_register($12, 4, val)
>> +
>> +#define read_c0_mailbox0()        __read_32bit_c0_register($20, 0)
>> +#define write_c0_mailbox0(val) __write_32bit_c0_register($20, 0, val)
>> +
>> +#define read_c0_mailbox1()        __read_32bit_c0_register($20, 1)
>> +#define write_c0_mailbox1(val) __write_32bit_c0_register($20, 1, val)
>> +
>> +#define smp_clr_pending(mask) do {        \
>> +        unsigned int stat;        \
>> +        stat = read_c0_corestatus();    \
>> +        stat &= ~((mask) & 0xff);    \
>> +        write_c0_corestatus(stat);    \
>> +    } while (0)
>> +
>> +/*
>> + * Core Control register
>> + */
>> +#define CORECTRL_SLEEP1M_SHIFT    17
>> +#define CORECTRL_SLEEP1M    (_ULCAST_(0x1) << CORECTRL_SLEEP1M_SHIFT)
>> +#define CORECTRL_SLEEP0M_SHIFT    16
>> +#define CORECTRL_SLEEP0M    (_ULCAST_(0x1) << CORECTRL_SLEEP0M_SHIFT)
>> +#define CORECTRL_RPC1_SHIFT    9
>> +#define CORECTRL_RPC1        (_ULCAST_(0x1) << CORECTRL_RPC1_SHIFT)
>> +#define CORECTRL_RPC0_SHIFT    8
>> +#define CORECTRL_RPC0        (_ULCAST_(0x1) << CORECTRL_RPC0_SHIFT)
>> +#define CORECTRL_SWRST1_SHIFT    1
>> +#define CORECTRL_SWRST1        (_ULCAST_(0x1) << CORECTRL_SWRST1_SHIFT)
>> +#define CORECTRL_SWRST0_SHIFT    0
>> +#define CORECTRL_SWRST0        (_ULCAST_(0x1) << CORECTRL_SWRST0_SHIFT)
>> +
>> +/*
>> + * Core Status register
>> + */
>> +#define CORESTATUS_SLEEP1_SHIFT    17
>> +#define CORESTATUS_SLEEP1    (_ULCAST_(0x1) << CORESTATUS_SLEEP1_SHIFT)
>> +#define CORESTATUS_SLEEP0_SHIFT    16
>> +#define CORESTATUS_SLEEP0    (_ULCAST_(0x1) << CORESTATUS_SLEEP0_SHIFT)
>> +#define CORESTATUS_IRQ1P_SHIFT    9
>> +#define CORESTATUS_IRQ1P    (_ULCAST_(0x1) << CORESTATUS_IRQ1P_SHIFT)
>> +#define CORESTATUS_IRQ0P_SHIFT    8
>> +#define CORESTATUS_IRQ0P    (_ULCAST_(0x1) << CORESTATUS_IRQ8P_SHIFT)
>> +#define CORESTATUS_MIRQ1P_SHIFT    1
>> +#define CORESTATUS_MIRQ1P    (_ULCAST_(0x1) << CORESTATUS_MIRQ1P_SHIFT)
>> +#define CORESTATUS_MIRQ0P_SHIFT    0
>> +#define CORESTATUS_MIRQ0P    (_ULCAST_(0x1) << CORESTATUS_MIRQ0P_SHIFT)
>> +
>> +/*
>> + * Reset Entry & IRQ Mask register
>> + */
>> +#define REIM_ENTRY_SHIFT    16
>> +#define REIM_ENTRY        (_ULCAST_(0xffff) << REIM_ENTRY_SHIFT)
>> +#define REIM_IRQ1M_SHIFT    9
>> +#define REIM_IRQ1M        (_ULCAST_(0x1) << REIM_IRQ1M_SHIFT)
>> +#define REIM_IRQ0M_SHIFT    8
>> +#define REIM_IRQ0M        (_ULCAST_(0x1) << REIM_IRQ0M_SHIFT)
>> +#define REIM_MBOXIRQ1M_SHIFT    1
>> +#define REIM_MBOXIRQ1M        (_ULCAST_(0x1) << REIM_MBOXIRQ1M_SHIFT)
>> +#define REIM_MBOXIRQ0M_SHIFT    0
>> +#define REIM_MBOXIRQ0M        (_ULCAST_(0x1) << REIM_MBOXIRQ0M_SHIFT)
>> +
>> +#ifdef CONFIG_SMP
>> +
>> +extern void jz4780_smp_wait_irqoff(void);
>> +
>> +extern void jz4780_smp_init(void);
>> +extern void jz4780_secondary_cpu_entry(void);
>> +
>> +#else /* !CONFIG_SMP */
>> +
>> +static inline void jz4780_smp_init(void) { }
>> +
>> +#endif /* !CONFIG_SMP */
>> +
>> +#endif /* __MIPS_ASM_MACH_JZ4740_JZ4780_SMP_H__ */
>> diff --git a/arch/mips/jz4740/Kconfig b/arch/mips/jz4740/Kconfig
>> index 412d2fa..0239597 100644
>> --- a/arch/mips/jz4740/Kconfig
>> +++ b/arch/mips/jz4740/Kconfig
>> @@ -34,9 +34,12 @@ config MACH_JZ4770
>>
>>  config MACH_JZ4780
>>      bool
>> +    select GENERIC_CLOCKEVENTS_BROADCAST if SMP
>>      select MIPS_CPU_SCACHE
>> +    select NR_CPUS_DEFAULT_2
>>      select SYS_HAS_CPU_MIPS32_R2
>>      select SYS_SUPPORTS_HIGHMEM
>> +    select SYS_SUPPORTS_SMP
>>
>>  config MACH_X1000
>>      bool
>> diff --git a/arch/mips/jz4740/Makefile b/arch/mips/jz4740/Makefile
>> index 6de14c0..0a0f024 100644
>> --- a/arch/mips/jz4740/Makefile
>> +++ b/arch/mips/jz4740/Makefile
>> @@ -12,3 +12,8 @@ CFLAGS_setup.o = -I$(src)/../../../scripts/dtc/libfdt
>>  # PM support
>>
>>  obj-$(CONFIG_PM) += pm.o
>> +
>> +# SMP support
>> +
>> +obj-$(CONFIG_SMP) += smp.o
>> +obj-$(CONFIG_SMP) += smp-entry.o
>> diff --git a/arch/mips/jz4740/prom.c b/arch/mips/jz4740/prom.c
>> index ff4555c..a79159e 100644
>> --- a/arch/mips/jz4740/prom.c
>> +++ b/arch/mips/jz4740/prom.c
>> @@ -8,10 +8,14 @@
>>
>>  #include <asm/bootinfo.h>
>>  #include <asm/fw/fw.h>
>> +#include <asm/mach-jz4740/jz4780-smp.h>
>>
>>  void __init prom_init(void)
>>  {
>>      fw_init_cmdline();
>> +#if defined(CONFIG_MACH_JZ4780) && defined(CONFIG_SMP)
>> +    jz4780_smp_init();
>> +#endif
>
> You should not check for defined(CONFIG_MACH_JZ4780), because that 
> means you cannot have a kernel that works on multiple SoCs at the same 
> time. Instead, check the value of "mips_machtype".

Sure, I will change it in next version.

Thanks and best regards!

>
> -Paul
>
>>  }
>>
>>  void __init prom_free_prom_memory(void)
>> diff --git a/arch/mips/jz4740/smp-entry.S b/arch/mips/jz4740/smp-entry.S
>> new file mode 100644
>> index 00000000..20049a3
>> --- /dev/null
>> +++ b/arch/mips/jz4740/smp-entry.S
>> @@ -0,0 +1,57 @@
>> +/* SPDX-License-Identifier: GPL-2.0-or-later */
>> +/*
>> + *  Copyright (C) 2013, Paul Burton <paul.burton@imgtec.com>
>> + *  JZ4780 SMP entry point
>> + */
>> +
>> +#include <asm/addrspace.h>
>> +#include <asm/asm.h>
>> +#include <asm/asmmacro.h>
>> +#include <asm/cacheops.h>
>> +#include <asm/mipsregs.h>
>> +
>> +#define CACHE_SIZE (32 * 1024)
>> +#define CACHE_LINESIZE 32
>> +
>> +.extern jz4780_cpu_entry_sp
>> +.extern jz4780_cpu_entry_gp
>> +
>> +.section .text.smp-entry
>> +.balign 0x10000
>> +.set noreorder
>> +LEAF(jz4780_secondary_cpu_entry)
>> +    mtc0    zero, CP0_CAUSE
>> +
>> +    li    t0, ST0_CU0
>> +    mtc0    t0, CP0_STATUS
>> +
>> +    /* cache setup */
>> +    li    t0, KSEG0
>> +    ori    t1, t0, CACHE_SIZE
>> +    mtc0    zero, CP0_TAGLO, 0
>> +1:    cache    Index_Store_Tag_I, 0(t0)
>> +    cache    Index_Store_Tag_D, 0(t0)
>> +    bne    t0, t1, 1b
>> +     addiu    t0, t0, CACHE_LINESIZE
>> +
>> +    /* kseg0 cache attribute */
>> +    mfc0    t0, CP0_CONFIG, 0
>> +    ori    t0, t0, CONF_CM_CACHABLE_NONCOHERENT
>> +    mtc0    t0, CP0_CONFIG, 0
>> +
>> +    /* pagemask */
>> +    mtc0    zero, CP0_PAGEMASK, 0
>> +
>> +    /* retrieve sp */
>> +    la    t0, jz4780_cpu_entry_sp
>> +    lw    sp, 0(t0)
>> +
>> +    /* retrieve gp */
>> +    la    t0, jz4780_cpu_entry_gp
>> +    lw    gp, 0(t0)
>> +
>> +    /* jump to the kernel in kseg0 */
>> +    la    t0, smp_bootstrap
>> +    jr    t0
>> +     nop
>> +    END(jz4780_secondary_cpu_entry)
>> diff --git a/arch/mips/jz4740/smp.c b/arch/mips/jz4740/smp.c
>> new file mode 100644
>> index 00000000..826fd0f
>> --- /dev/null
>> +++ b/arch/mips/jz4740/smp.c
>> @@ -0,0 +1,283 @@
>> +// SPDX-License-Identifier: GPL-2.0
>> +/*
>> + *  Copyright (C) 2013, Paul Burton <paul.burton@imgtec.com>
>> + *  JZ4780 SMP
>> + */
>> +
>> +#include <linux/clk.h>
>> +#include <linux/delay.h>
>> +#include <linux/interrupt.h>
>> +#include <linux/of.h>
>> +#include <linux/sched.h>
>> +#include <linux/sched/task_stack.h>
>> +#include <linux/smp.h>
>> +#include <linux/tick.h>
>> +#include <asm/mach-jz4740/jz4780-smp.h>
>> +#include <asm/r4kcache.h>
>> +#include <asm/smp-ops.h>
>> +
>> +static struct clk *cpu_clock_gates[CONFIG_NR_CPUS] = { NULL };
>> +
>> +u32 jz4780_cpu_entry_sp;
>> +u32 jz4780_cpu_entry_gp;
>> +
>> +static struct cpumask cpu_running;
>> +
>> +static DEFINE_SPINLOCK(smp_lock);
>> +
>> +/*
>> + * The Ingenic jz4780 SMP variant has to write back dirty cache 
>> lines before
>> + * executing wait. The CPU & cache clock will be gated until we 
>> return from
>> + * the wait, and if another core attempts to access data from our 
>> data cache
>> + * during this time then it will lock up.
>> + */
>> +void jz4780_smp_wait_irqoff(void)
>> +{
>> +    unsigned long pending = read_c0_cause() & read_c0_status() & 
>> CAUSEF_IP;
>> +
>> +    /*
>> +     * Going to idle has a significant overhead due to the cache 
>> flush so
>> +     * try to avoid it if we'll immediately be woken again due to an 
>> IRQ.
>> +     */
>> +    if (!need_resched() && !pending) {
>> +        r4k_blast_dcache();
>> +
>> +        __asm__(
>> +        "    .set push    \n"
>> +        "    .set mips3    \n"
>> +        "    sync        \n"
>> +        "    wait        \n"
>> +        "    .set pop    \n");
>> +    }
>> +
>> +    local_irq_enable();
>> +}
>> +
>> +static irqreturn_t mbox_handler(int irq, void *dev_id)
>> +{
>> +    int cpu = smp_processor_id();
>> +    u32 action, status;
>> +
>> +    spin_lock(&smp_lock);
>> +
>> +    switch (cpu) {
>> +    case 0:
>> +        action = read_c0_mailbox0();
>> +        write_c0_mailbox0(0);
>> +        break;
>> +    case 1:
>> +        action = read_c0_mailbox1();
>> +        write_c0_mailbox1(0);
>> +        break;
>> +    default:
>> +        panic("unhandled cpu %d!", cpu);
>> +    }
>> +
>> +    /* clear pending mailbox interrupt */
>> +    status = read_c0_corestatus();
>> +    status &= ~(CORESTATUS_MIRQ0P << cpu);
>> +    write_c0_corestatus(status);
>> +
>> +    spin_unlock(&smp_lock);
>> +
>> +    if (action & SMP_RESCHEDULE_YOURSELF)
>> +        scheduler_ipi();
>> +    if (action & SMP_CALL_FUNCTION)
>> +        generic_smp_call_function_interrupt();
>> +
>> +    return IRQ_HANDLED;
>> +}
>> +
>> +static void jz4780_smp_setup(void)
>> +{
>> +    u32 addr, reim;
>> +    int cpu;
>> +
>> +    reim = read_c0_reim();
>> +
>> +    for (cpu = 0; cpu < NR_CPUS; cpu++) {
>> +        __cpu_number_map[cpu] = cpu;
>> +        __cpu_logical_map[cpu] = cpu;
>> +        set_cpu_possible(cpu, true);
>> +    }
>> +
>> +    /* mask mailbox interrupts for this core */
>> +    reim &= ~REIM_MBOXIRQ0M;
>> +    write_c0_reim(reim);
>> +
>> +    /* clear mailboxes & pending mailbox IRQs */
>> +    write_c0_mailbox0(0);
>> +    write_c0_mailbox1(0);
>> +    write_c0_corestatus(0);
>> +
>> +    /* set reset entry point */
>> +    addr = KSEG1ADDR((u32)&jz4780_secondary_cpu_entry);
>> +    WARN_ON(addr & ~REIM_ENTRY);
>> +    reim &= ~REIM_ENTRY;
>> +    reim |= addr & REIM_ENTRY;
>> +
>> +    /* unmask mailbox interrupts for this core */
>> +    reim |= REIM_MBOXIRQ0M;
>> +    write_c0_reim(reim);
>> +    set_c0_status(STATUSF_IP3);
>> +    irq_enable_hazard();
>> +
>> +    cpumask_set_cpu(cpu, &cpu_running);
>> +}
>> +
>> +static void jz4780_smp_prepare_cpus(unsigned int max_cpus)
>> +{
>> +    struct device_node *cpu_node;
>> +    unsigned cpu, ctrl;
>> +    int err;
>> +
>> +    /* setup the mailbox IRQ */
>> +    err = request_irq(MIPS_CPU_IRQ_BASE + 3, mbox_handler,
>> +                IRQF_PERCPU | IRQF_NO_THREAD, "core mailbox", NULL);
>> +    if (err)
>> +        pr_err("request_irq() on core mailbox failed\n");
>> +
>> +    init_cpu_present(cpu_possible_mask);
>> +
>> +    ctrl = read_c0_corectrl();
>> +
>> +    for (cpu = 0; cpu < max_cpus; cpu++) {
>> +        /* use reset entry point from REIM register */
>> +        ctrl |= CORECTRL_RPC0 << cpu;
>> +    }
>> +
>> +    for_each_of_cpu_node(cpu_node) {
>> +        cpu = of_cpu_node_to_id(cpu_node);
>> +        if (cpu < 0) {
>> +            pr_err("Failed to read index of %s\n",
>> +                   cpu_node->full_name);
>> +            continue;
>> +        }
>> +
>> +        cpu_clock_gates[cpu] = of_clk_get(cpu_node, 0);
>> +        if (IS_ERR(cpu_clock_gates[cpu])) {
>> +            cpu_clock_gates[cpu] = NULL;
>> +            continue;
>> +        }
>> +
>> +        err = clk_prepare(cpu_clock_gates[cpu]);
>> +        if (err)
>> +            pr_err("Failed to prepare CPU clock gate\n");
>> +    }
>> +
>> +    write_c0_corectrl(ctrl);
>> +}
>> +
>> +static int jz4780_boot_secondary(int cpu, struct task_struct *idle)
>> +{
>> +    unsigned long flags;
>> +    u32 ctrl;
>> +
>> +    spin_lock_irqsave(&smp_lock, flags);
>> +
>> +    /* ensure the core is in reset */
>> +    ctrl = read_c0_corectrl();
>> +    ctrl |= CORECTRL_SWRST0 << cpu;
>> +    write_c0_corectrl(ctrl);
>> +
>> +    /* ungate core clock */
>> +    if (cpu_clock_gates[cpu])
>> +        clk_enable(cpu_clock_gates[cpu]);
>> +
>> +    /* set entry sp/gp register values */
>> +    jz4780_cpu_entry_sp = __KSTK_TOS(idle);
>> +    jz4780_cpu_entry_gp = (u32)task_thread_info(idle);
>> +    smp_wmb();
>> +
>> +    /* take the core out of reset */
>> +    ctrl &= ~(CORECTRL_SWRST0 << cpu);
>> +    write_c0_corectrl(ctrl);
>> +
>> +    cpumask_set_cpu(cpu, &cpu_running);
>> +
>> +    spin_unlock_irqrestore(&smp_lock, flags);
>> +
>> +    return 0;
>> +}
>> +
>> +static void jz4780_init_secondary(void)
>> +{
>> +}
>> +
>> +static void jz4780_smp_finish(void)
>> +{
>> +    u32 reim;
>> +
>> +    spin_lock(&smp_lock);
>> +
>> +    /* unmask mailbox interrupts for this core */
>> +    reim = read_c0_reim();
>> +    reim |= REIM_MBOXIRQ0M << smp_processor_id();
>> +    write_c0_reim(reim);
>> +
>> +    spin_unlock(&smp_lock);
>> +
>> +    /* unmask interrupts for this core */
>> +    change_c0_status(ST0_IM, STATUSF_IP3 | STATUSF_IP2 |
>> +             STATUSF_IP1 | STATUSF_IP0);
>> +    irq_enable_hazard();
>> +
>> +    /* force broadcast timer */
>> +    tick_broadcast_force();
>> +}
>> +
>> +static void jz4780_send_ipi_single_locked(int cpu, unsigned int action)
>> +{
>> +    u32 mbox;
>> +
>> +    switch (cpu) {
>> +    case 0:
>> +        mbox = read_c0_mailbox0();
>> +        write_c0_mailbox0(mbox | action);
>> +        break;
>> +    case 1:
>> +        mbox = read_c0_mailbox1();
>> +        write_c0_mailbox1(mbox | action);
>> +        break;
>> +    default:
>> +        panic("unhandled cpu %d!", cpu);
>> +    }
>> +}
>> +
>> +static void jz4780_send_ipi_single(int cpu, unsigned int action)
>> +{
>> +    unsigned long flags;
>> +
>> +    spin_lock_irqsave(&smp_lock, flags);
>> +    jz4780_send_ipi_single_locked(cpu, action);
>> +    spin_unlock_irqrestore(&smp_lock, flags);
>> +}
>> +
>> +static void jz4780_send_ipi_mask(const struct cpumask *mask,
>> +                 unsigned int action)
>> +{
>> +    unsigned long flags;
>> +    int cpu;
>> +
>> +    spin_lock_irqsave(&smp_lock, flags);
>> +
>> +    for_each_cpu(cpu, mask)
>> +        jz4780_send_ipi_single_locked(cpu, action);
>> +
>> +    spin_unlock_irqrestore(&smp_lock, flags);
>> +}
>> +
>> +static struct plat_smp_ops jz4780_smp_ops = {
>> +    .send_ipi_single = jz4780_send_ipi_single,
>> +    .send_ipi_mask = jz4780_send_ipi_mask,
>> +    .init_secondary = jz4780_init_secondary,
>> +    .smp_finish = jz4780_smp_finish,
>> +    .boot_secondary = jz4780_boot_secondary,
>> +    .smp_setup = jz4780_smp_setup,
>> +    .prepare_cpus = jz4780_smp_prepare_cpus,
>> +};
>> +
>> +void jz4780_smp_init(void)
>> +{
>> +    register_smp_ops(&jz4780_smp_ops);
>> +}
>> diff --git a/arch/mips/kernel/idle.c b/arch/mips/kernel/idle.c
>> index 37f8e78..a406de3 100644
>> --- a/arch/mips/kernel/idle.c
>> +++ b/arch/mips/kernel/idle.c
>> @@ -19,6 +19,10 @@
>>  #include <asm/idle.h>
>>  #include <asm/mipsregs.h>
>>
>> +#ifdef CONFIG_MACH_JZ4780
>> +# include <asm/mach-jz4740/jz4780-smp.h>
>> +#endif
>> +
>>  /*
>>   * Not all of the MIPS CPUs have the "wait" instruction available. 
>> Moreover,
>>   * the implementation of the "wait" feature differs between CPU 
>> families. This
>> @@ -172,7 +176,6 @@ void __init check_wait(void)
>>      case CPU_CAVIUM_OCTEON_PLUS:
>>      case CPU_CAVIUM_OCTEON2:
>>      case CPU_CAVIUM_OCTEON3:
>> -    case CPU_XBURST:
>>      case CPU_LOONGSON32:
>>      case CPU_XLR:
>>      case CPU_XLP:
>> @@ -246,6 +249,15 @@ void __init check_wait(void)
>>             cpu_wait = r4k_wait;
>>           */
>>          break;
>> +    case CPU_XBURST:
>> +#if defined(CONFIG_MACH_JZ4780) && defined(CONFIG_SMP)
>> +        if (NR_CPUS > 1)
>> +            cpu_wait = jz4780_smp_wait_irqoff;
>> +        else
>> +            cpu_wait = r4k_wait;
>> +#else
>> +        cpu_wait = r4k_wait;
>> +#endif
>>      default:
>>          break;
>>      }
>> -- 
>> 2.7.4
>>
>
diff mbox series

Patch

diff --git a/arch/mips/include/asm/mach-jz4740/jz4780-smp.h b/arch/mips/include/asm/mach-jz4740/jz4780-smp.h
new file mode 100644
index 00000000..3f592ce
--- /dev/null
+++ b/arch/mips/include/asm/mach-jz4740/jz4780-smp.h
@@ -0,0 +1,91 @@ 
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+/*
+ *  Copyright (C) 2013, Paul Burton <paul.burton@imgtec.com>
+ *  JZ4780 SMP definitions
+ */
+
+#ifndef __MIPS_ASM_MACH_JZ4740_JZ4780_SMP_H__
+#define __MIPS_ASM_MACH_JZ4740_JZ4780_SMP_H__
+
+#define read_c0_corectrl()		__read_32bit_c0_register($12, 2)
+#define write_c0_corectrl(val)		__write_32bit_c0_register($12, 2, val)
+
+#define read_c0_corestatus()		__read_32bit_c0_register($12, 3)
+#define write_c0_corestatus(val)	__write_32bit_c0_register($12, 3, val)
+
+#define read_c0_reim()			__read_32bit_c0_register($12, 4)
+#define write_c0_reim(val)		__write_32bit_c0_register($12, 4, val)
+
+#define read_c0_mailbox0()		__read_32bit_c0_register($20, 0)
+#define write_c0_mailbox0(val)		__write_32bit_c0_register($20, 0, val)
+
+#define read_c0_mailbox1()		__read_32bit_c0_register($20, 1)
+#define write_c0_mailbox1(val)		__write_32bit_c0_register($20, 1, val)
+
+#define smp_clr_pending(mask) do {		\
+		unsigned int stat;		\
+		stat = read_c0_corestatus();	\
+		stat &= ~((mask) & 0xff);	\
+		write_c0_corestatus(stat);	\
+	} while (0)
+
+/*
+ * Core Control register
+ */
+#define CORECTRL_SLEEP1M_SHIFT	17
+#define CORECTRL_SLEEP1M	(_ULCAST_(0x1) << CORECTRL_SLEEP1M_SHIFT)
+#define CORECTRL_SLEEP0M_SHIFT	16
+#define CORECTRL_SLEEP0M	(_ULCAST_(0x1) << CORECTRL_SLEEP0M_SHIFT)
+#define CORECTRL_RPC1_SHIFT	9
+#define CORECTRL_RPC1		(_ULCAST_(0x1) << CORECTRL_RPC1_SHIFT)
+#define CORECTRL_RPC0_SHIFT	8
+#define CORECTRL_RPC0		(_ULCAST_(0x1) << CORECTRL_RPC0_SHIFT)
+#define CORECTRL_SWRST1_SHIFT	1
+#define CORECTRL_SWRST1		(_ULCAST_(0x1) << CORECTRL_SWRST1_SHIFT)
+#define CORECTRL_SWRST0_SHIFT	0
+#define CORECTRL_SWRST0		(_ULCAST_(0x1) << CORECTRL_SWRST0_SHIFT)
+
+/*
+ * Core Status register
+ */
+#define CORESTATUS_SLEEP1_SHIFT	17
+#define CORESTATUS_SLEEP1	(_ULCAST_(0x1) << CORESTATUS_SLEEP1_SHIFT)
+#define CORESTATUS_SLEEP0_SHIFT	16
+#define CORESTATUS_SLEEP0	(_ULCAST_(0x1) << CORESTATUS_SLEEP0_SHIFT)
+#define CORESTATUS_IRQ1P_SHIFT	9
+#define CORESTATUS_IRQ1P	(_ULCAST_(0x1) << CORESTATUS_IRQ1P_SHIFT)
+#define CORESTATUS_IRQ0P_SHIFT	8
+#define CORESTATUS_IRQ0P	(_ULCAST_(0x1) << CORESTATUS_IRQ8P_SHIFT)
+#define CORESTATUS_MIRQ1P_SHIFT	1
+#define CORESTATUS_MIRQ1P	(_ULCAST_(0x1) << CORESTATUS_MIRQ1P_SHIFT)
+#define CORESTATUS_MIRQ0P_SHIFT	0
+#define CORESTATUS_MIRQ0P	(_ULCAST_(0x1) << CORESTATUS_MIRQ0P_SHIFT)
+
+/*
+ * Reset Entry & IRQ Mask register
+ */
+#define REIM_ENTRY_SHIFT	16
+#define REIM_ENTRY		(_ULCAST_(0xffff) << REIM_ENTRY_SHIFT)
+#define REIM_IRQ1M_SHIFT	9
+#define REIM_IRQ1M		(_ULCAST_(0x1) << REIM_IRQ1M_SHIFT)
+#define REIM_IRQ0M_SHIFT	8
+#define REIM_IRQ0M		(_ULCAST_(0x1) << REIM_IRQ0M_SHIFT)
+#define REIM_MBOXIRQ1M_SHIFT	1
+#define REIM_MBOXIRQ1M		(_ULCAST_(0x1) << REIM_MBOXIRQ1M_SHIFT)
+#define REIM_MBOXIRQ0M_SHIFT	0
+#define REIM_MBOXIRQ0M		(_ULCAST_(0x1) << REIM_MBOXIRQ0M_SHIFT)
+
+#ifdef CONFIG_SMP
+
+extern void jz4780_smp_wait_irqoff(void);
+
+extern void jz4780_smp_init(void);
+extern void jz4780_secondary_cpu_entry(void);
+
+#else /* !CONFIG_SMP */
+
+static inline void jz4780_smp_init(void) { }
+
+#endif /* !CONFIG_SMP */
+
+#endif /* __MIPS_ASM_MACH_JZ4740_JZ4780_SMP_H__ */
diff --git a/arch/mips/jz4740/Kconfig b/arch/mips/jz4740/Kconfig
index 412d2fa..0239597 100644
--- a/arch/mips/jz4740/Kconfig
+++ b/arch/mips/jz4740/Kconfig
@@ -34,9 +34,12 @@  config MACH_JZ4770
 
 config MACH_JZ4780
 	bool
+	select GENERIC_CLOCKEVENTS_BROADCAST if SMP
 	select MIPS_CPU_SCACHE
+	select NR_CPUS_DEFAULT_2
 	select SYS_HAS_CPU_MIPS32_R2
 	select SYS_SUPPORTS_HIGHMEM
+	select SYS_SUPPORTS_SMP
 
 config MACH_X1000
 	bool
diff --git a/arch/mips/jz4740/Makefile b/arch/mips/jz4740/Makefile
index 6de14c0..0a0f024 100644
--- a/arch/mips/jz4740/Makefile
+++ b/arch/mips/jz4740/Makefile
@@ -12,3 +12,8 @@  CFLAGS_setup.o = -I$(src)/../../../scripts/dtc/libfdt
 # PM support
 
 obj-$(CONFIG_PM) += pm.o
+
+# SMP support
+
+obj-$(CONFIG_SMP) += smp.o
+obj-$(CONFIG_SMP) += smp-entry.o
diff --git a/arch/mips/jz4740/prom.c b/arch/mips/jz4740/prom.c
index ff4555c..a79159e 100644
--- a/arch/mips/jz4740/prom.c
+++ b/arch/mips/jz4740/prom.c
@@ -8,10 +8,14 @@ 
 
 #include <asm/bootinfo.h>
 #include <asm/fw/fw.h>
+#include <asm/mach-jz4740/jz4780-smp.h>
 
 void __init prom_init(void)
 {
 	fw_init_cmdline();
+#if defined(CONFIG_MACH_JZ4780) && defined(CONFIG_SMP)
+	jz4780_smp_init();
+#endif
 }
 
 void __init prom_free_prom_memory(void)
diff --git a/arch/mips/jz4740/smp-entry.S b/arch/mips/jz4740/smp-entry.S
new file mode 100644
index 00000000..20049a3
--- /dev/null
+++ b/arch/mips/jz4740/smp-entry.S
@@ -0,0 +1,57 @@ 
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+/*
+ *  Copyright (C) 2013, Paul Burton <paul.burton@imgtec.com>
+ *  JZ4780 SMP entry point
+ */
+
+#include <asm/addrspace.h>
+#include <asm/asm.h>
+#include <asm/asmmacro.h>
+#include <asm/cacheops.h>
+#include <asm/mipsregs.h>
+
+#define CACHE_SIZE (32 * 1024)
+#define CACHE_LINESIZE 32
+
+.extern jz4780_cpu_entry_sp
+.extern jz4780_cpu_entry_gp
+
+.section .text.smp-entry
+.balign 0x10000
+.set noreorder
+LEAF(jz4780_secondary_cpu_entry)
+	mtc0	zero, CP0_CAUSE
+
+	li	t0, ST0_CU0
+	mtc0	t0, CP0_STATUS
+
+	/* cache setup */
+	li	t0, KSEG0
+	ori	t1, t0, CACHE_SIZE
+	mtc0	zero, CP0_TAGLO, 0
+1:	cache	Index_Store_Tag_I, 0(t0)
+	cache	Index_Store_Tag_D, 0(t0)
+	bne	t0, t1, 1b
+	 addiu	t0, t0, CACHE_LINESIZE
+
+	/* kseg0 cache attribute */
+	mfc0	t0, CP0_CONFIG, 0
+	ori	t0, t0, CONF_CM_CACHABLE_NONCOHERENT
+	mtc0	t0, CP0_CONFIG, 0
+
+	/* pagemask */
+	mtc0	zero, CP0_PAGEMASK, 0
+
+	/* retrieve sp */
+	la	t0, jz4780_cpu_entry_sp
+	lw	sp, 0(t0)
+
+	/* retrieve gp */
+	la	t0, jz4780_cpu_entry_gp
+	lw	gp, 0(t0)
+
+	/* jump to the kernel in kseg0 */
+	la	t0, smp_bootstrap
+	jr	t0
+	 nop
+	END(jz4780_secondary_cpu_entry)
diff --git a/arch/mips/jz4740/smp.c b/arch/mips/jz4740/smp.c
new file mode 100644
index 00000000..826fd0f
--- /dev/null
+++ b/arch/mips/jz4740/smp.c
@@ -0,0 +1,283 @@ 
+// SPDX-License-Identifier: GPL-2.0
+/*
+ *  Copyright (C) 2013, Paul Burton <paul.burton@imgtec.com>
+ *  JZ4780 SMP
+ */
+
+#include <linux/clk.h>
+#include <linux/delay.h>
+#include <linux/interrupt.h>
+#include <linux/of.h>
+#include <linux/sched.h>
+#include <linux/sched/task_stack.h>
+#include <linux/smp.h>
+#include <linux/tick.h>
+#include <asm/mach-jz4740/jz4780-smp.h>
+#include <asm/r4kcache.h>
+#include <asm/smp-ops.h>
+
+static struct clk *cpu_clock_gates[CONFIG_NR_CPUS] = { NULL };
+
+u32 jz4780_cpu_entry_sp;
+u32 jz4780_cpu_entry_gp;
+
+static struct cpumask cpu_running;
+
+static DEFINE_SPINLOCK(smp_lock);
+
+/*
+ * The Ingenic jz4780 SMP variant has to write back dirty cache lines before
+ * executing wait. The CPU & cache clock will be gated until we return from
+ * the wait, and if another core attempts to access data from our data cache
+ * during this time then it will lock up.
+ */
+void jz4780_smp_wait_irqoff(void)
+{
+	unsigned long pending = read_c0_cause() & read_c0_status() & CAUSEF_IP;
+
+	/*
+	 * Going to idle has a significant overhead due to the cache flush so
+	 * try to avoid it if we'll immediately be woken again due to an IRQ.
+	 */
+	if (!need_resched() && !pending) {
+		r4k_blast_dcache();
+
+		__asm__(
+		"	.set push	\n"
+		"	.set mips3	\n"
+		"	sync		\n"
+		"	wait		\n"
+		"	.set pop	\n");
+	}
+
+	local_irq_enable();
+}
+
+static irqreturn_t mbox_handler(int irq, void *dev_id)
+{
+	int cpu = smp_processor_id();
+	u32 action, status;
+
+	spin_lock(&smp_lock);
+
+	switch (cpu) {
+	case 0:
+		action = read_c0_mailbox0();
+		write_c0_mailbox0(0);
+		break;
+	case 1:
+		action = read_c0_mailbox1();
+		write_c0_mailbox1(0);
+		break;
+	default:
+		panic("unhandled cpu %d!", cpu);
+	}
+
+	/* clear pending mailbox interrupt */
+	status = read_c0_corestatus();
+	status &= ~(CORESTATUS_MIRQ0P << cpu);
+	write_c0_corestatus(status);
+
+	spin_unlock(&smp_lock);
+
+	if (action & SMP_RESCHEDULE_YOURSELF)
+		scheduler_ipi();
+	if (action & SMP_CALL_FUNCTION)
+		generic_smp_call_function_interrupt();
+
+	return IRQ_HANDLED;
+}
+
+static void jz4780_smp_setup(void)
+{
+	u32 addr, reim;
+	int cpu;
+
+	reim = read_c0_reim();
+
+	for (cpu = 0; cpu < NR_CPUS; cpu++) {
+		__cpu_number_map[cpu] = cpu;
+		__cpu_logical_map[cpu] = cpu;
+		set_cpu_possible(cpu, true);
+	}
+
+	/* mask mailbox interrupts for this core */
+	reim &= ~REIM_MBOXIRQ0M;
+	write_c0_reim(reim);
+
+	/* clear mailboxes & pending mailbox IRQs */
+	write_c0_mailbox0(0);
+	write_c0_mailbox1(0);
+	write_c0_corestatus(0);
+
+	/* set reset entry point */
+	addr = KSEG1ADDR((u32)&jz4780_secondary_cpu_entry);
+	WARN_ON(addr & ~REIM_ENTRY);
+	reim &= ~REIM_ENTRY;
+	reim |= addr & REIM_ENTRY;
+
+	/* unmask mailbox interrupts for this core */
+	reim |= REIM_MBOXIRQ0M;
+	write_c0_reim(reim);
+	set_c0_status(STATUSF_IP3);
+	irq_enable_hazard();
+
+	cpumask_set_cpu(cpu, &cpu_running);
+}
+
+static void jz4780_smp_prepare_cpus(unsigned int max_cpus)
+{
+	struct device_node *cpu_node;
+	unsigned cpu, ctrl;
+	int err;
+
+	/* setup the mailbox IRQ */
+	err = request_irq(MIPS_CPU_IRQ_BASE + 3, mbox_handler,
+				IRQF_PERCPU | IRQF_NO_THREAD, "core mailbox", NULL);
+	if (err)
+		pr_err("request_irq() on core mailbox failed\n");
+
+	init_cpu_present(cpu_possible_mask);
+
+	ctrl = read_c0_corectrl();
+
+	for (cpu = 0; cpu < max_cpus; cpu++) {
+		/* use reset entry point from REIM register */
+		ctrl |= CORECTRL_RPC0 << cpu;
+	}
+
+	for_each_of_cpu_node(cpu_node) {
+		cpu = of_cpu_node_to_id(cpu_node);
+		if (cpu < 0) {
+			pr_err("Failed to read index of %s\n",
+			       cpu_node->full_name);
+			continue;
+		}
+
+		cpu_clock_gates[cpu] = of_clk_get(cpu_node, 0);
+		if (IS_ERR(cpu_clock_gates[cpu])) {
+			cpu_clock_gates[cpu] = NULL;
+			continue;
+		}
+
+		err = clk_prepare(cpu_clock_gates[cpu]);
+		if (err)
+			pr_err("Failed to prepare CPU clock gate\n");
+	}
+
+	write_c0_corectrl(ctrl);
+}
+
+static int jz4780_boot_secondary(int cpu, struct task_struct *idle)
+{
+	unsigned long flags;
+	u32 ctrl;
+
+	spin_lock_irqsave(&smp_lock, flags);
+
+	/* ensure the core is in reset */
+	ctrl = read_c0_corectrl();
+	ctrl |= CORECTRL_SWRST0 << cpu;
+	write_c0_corectrl(ctrl);
+
+	/* ungate core clock */
+	if (cpu_clock_gates[cpu])
+		clk_enable(cpu_clock_gates[cpu]);
+
+	/* set entry sp/gp register values */
+	jz4780_cpu_entry_sp = __KSTK_TOS(idle);
+	jz4780_cpu_entry_gp = (u32)task_thread_info(idle);
+	smp_wmb();
+
+	/* take the core out of reset */
+	ctrl &= ~(CORECTRL_SWRST0 << cpu);
+	write_c0_corectrl(ctrl);
+
+	cpumask_set_cpu(cpu, &cpu_running);
+
+	spin_unlock_irqrestore(&smp_lock, flags);
+
+	return 0;
+}
+
+static void jz4780_init_secondary(void)
+{
+}
+
+static void jz4780_smp_finish(void)
+{
+	u32 reim;
+
+	spin_lock(&smp_lock);
+
+	/* unmask mailbox interrupts for this core */
+	reim = read_c0_reim();
+	reim |= REIM_MBOXIRQ0M << smp_processor_id();
+	write_c0_reim(reim);
+
+	spin_unlock(&smp_lock);
+
+	/* unmask interrupts for this core */
+	change_c0_status(ST0_IM, STATUSF_IP3 | STATUSF_IP2 |
+			 STATUSF_IP1 | STATUSF_IP0);
+	irq_enable_hazard();
+
+	/* force broadcast timer */
+	tick_broadcast_force();
+}
+
+static void jz4780_send_ipi_single_locked(int cpu, unsigned int action)
+{
+	u32 mbox;
+
+	switch (cpu) {
+	case 0:
+		mbox = read_c0_mailbox0();
+		write_c0_mailbox0(mbox | action);
+		break;
+	case 1:
+		mbox = read_c0_mailbox1();
+		write_c0_mailbox1(mbox | action);
+		break;
+	default:
+		panic("unhandled cpu %d!", cpu);
+	}
+}
+
+static void jz4780_send_ipi_single(int cpu, unsigned int action)
+{
+	unsigned long flags;
+
+	spin_lock_irqsave(&smp_lock, flags);
+	jz4780_send_ipi_single_locked(cpu, action);
+	spin_unlock_irqrestore(&smp_lock, flags);
+}
+
+static void jz4780_send_ipi_mask(const struct cpumask *mask,
+				 unsigned int action)
+{
+	unsigned long flags;
+	int cpu;
+
+	spin_lock_irqsave(&smp_lock, flags);
+
+	for_each_cpu(cpu, mask)
+		jz4780_send_ipi_single_locked(cpu, action);
+
+	spin_unlock_irqrestore(&smp_lock, flags);
+}
+
+static struct plat_smp_ops jz4780_smp_ops = {
+	.send_ipi_single = jz4780_send_ipi_single,
+	.send_ipi_mask = jz4780_send_ipi_mask,
+	.init_secondary = jz4780_init_secondary,
+	.smp_finish = jz4780_smp_finish,
+	.boot_secondary = jz4780_boot_secondary,
+	.smp_setup = jz4780_smp_setup,
+	.prepare_cpus = jz4780_smp_prepare_cpus,
+};
+
+void jz4780_smp_init(void)
+{
+	register_smp_ops(&jz4780_smp_ops);
+}
diff --git a/arch/mips/kernel/idle.c b/arch/mips/kernel/idle.c
index 37f8e78..a406de3 100644
--- a/arch/mips/kernel/idle.c
+++ b/arch/mips/kernel/idle.c
@@ -19,6 +19,10 @@ 
 #include <asm/idle.h>
 #include <asm/mipsregs.h>
 
+#ifdef CONFIG_MACH_JZ4780
+# include <asm/mach-jz4740/jz4780-smp.h>
+#endif
+
 /*
  * Not all of the MIPS CPUs have the "wait" instruction available. Moreover,
  * the implementation of the "wait" feature differs between CPU families. This
@@ -172,7 +176,6 @@  void __init check_wait(void)
 	case CPU_CAVIUM_OCTEON_PLUS:
 	case CPU_CAVIUM_OCTEON2:
 	case CPU_CAVIUM_OCTEON3:
-	case CPU_XBURST:
 	case CPU_LOONGSON32:
 	case CPU_XLR:
 	case CPU_XLP:
@@ -246,6 +249,15 @@  void __init check_wait(void)
 		   cpu_wait = r4k_wait;
 		 */
 		break;
+	case CPU_XBURST:
+#if defined(CONFIG_MACH_JZ4780) && defined(CONFIG_SMP)
+		if (NR_CPUS > 1)
+			cpu_wait = jz4780_smp_wait_irqoff;
+		else
+			cpu_wait = r4k_wait;
+#else
+		cpu_wait = r4k_wait;
+#endif
 	default:
 		break;
 	}