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Diffstat (limited to 'arch/sh/kernel/smp.c')
-rw-r--r-- | arch/sh/kernel/smp.c | 476 |
1 files changed, 476 insertions, 0 deletions
diff --git a/arch/sh/kernel/smp.c b/arch/sh/kernel/smp.c new file mode 100644 index 000000000..c483422ea --- /dev/null +++ b/arch/sh/kernel/smp.c @@ -0,0 +1,476 @@ +/* + * arch/sh/kernel/smp.c + * + * SMP support for the SuperH processors. + * + * Copyright (C) 2002 - 2010 Paul Mundt + * Copyright (C) 2006 - 2007 Akio Idehara + * + * This file is subject to the terms and conditions of the GNU General Public + * License. See the file "COPYING" in the main directory of this archive + * for more details. + */ +#include <linux/err.h> +#include <linux/cache.h> +#include <linux/cpumask.h> +#include <linux/delay.h> +#include <linux/init.h> +#include <linux/spinlock.h> +#include <linux/mm.h> +#include <linux/module.h> +#include <linux/cpu.h> +#include <linux/interrupt.h> +#include <linux/sched/mm.h> +#include <linux/sched/hotplug.h> +#include <linux/atomic.h> +#include <linux/clockchips.h> +#include <asm/processor.h> +#include <asm/mmu_context.h> +#include <asm/smp.h> +#include <asm/cacheflush.h> +#include <asm/sections.h> +#include <asm/setup.h> + +int __cpu_number_map[NR_CPUS]; /* Map physical to logical */ +int __cpu_logical_map[NR_CPUS]; /* Map logical to physical */ + +struct plat_smp_ops *mp_ops = NULL; + +/* State of each CPU */ +DEFINE_PER_CPU(int, cpu_state) = { 0 }; + +void register_smp_ops(struct plat_smp_ops *ops) +{ + if (mp_ops) + printk(KERN_WARNING "Overriding previously set SMP ops\n"); + + mp_ops = ops; +} + +static inline void smp_store_cpu_info(unsigned int cpu) +{ + struct sh_cpuinfo *c = cpu_data + cpu; + + memcpy(c, &boot_cpu_data, sizeof(struct sh_cpuinfo)); + + c->loops_per_jiffy = loops_per_jiffy; +} + +void __init smp_prepare_cpus(unsigned int max_cpus) +{ + unsigned int cpu = smp_processor_id(); + + init_new_context(current, &init_mm); + current_thread_info()->cpu = cpu; + mp_ops->prepare_cpus(max_cpus); + +#ifndef CONFIG_HOTPLUG_CPU + init_cpu_present(cpu_possible_mask); +#endif +} + +void __init smp_prepare_boot_cpu(void) +{ + unsigned int cpu = smp_processor_id(); + + __cpu_number_map[0] = cpu; + __cpu_logical_map[0] = cpu; + + set_cpu_online(cpu, true); + set_cpu_possible(cpu, true); + + per_cpu(cpu_state, cpu) = CPU_ONLINE; +} + +#ifdef CONFIG_HOTPLUG_CPU +void native_cpu_die(unsigned int cpu) +{ + unsigned int i; + + for (i = 0; i < 10; i++) { + smp_rmb(); + if (per_cpu(cpu_state, cpu) == CPU_DEAD) { + if (system_state == SYSTEM_RUNNING) + pr_info("CPU %u is now offline\n", cpu); + + return; + } + + msleep(100); + } + + pr_err("CPU %u didn't die...\n", cpu); +} + +int native_cpu_disable(unsigned int cpu) +{ + return cpu == 0 ? -EPERM : 0; +} + +void play_dead_common(void) +{ + idle_task_exit(); + irq_ctx_exit(raw_smp_processor_id()); + mb(); + + __this_cpu_write(cpu_state, CPU_DEAD); + local_irq_disable(); +} + +void native_play_dead(void) +{ + play_dead_common(); +} + +int __cpu_disable(void) +{ + unsigned int cpu = smp_processor_id(); + int ret; + + ret = mp_ops->cpu_disable(cpu); + if (ret) + return ret; + + /* + * Take this CPU offline. Once we clear this, we can't return, + * and we must not schedule until we're ready to give up the cpu. + */ + set_cpu_online(cpu, false); + + /* + * OK - migrate IRQs away from this CPU + */ + migrate_irqs(); + + /* + * Flush user cache and TLB mappings, and then remove this CPU + * from the vm mask set of all processes. + */ + flush_cache_all(); +#ifdef CONFIG_MMU + local_flush_tlb_all(); +#endif + + clear_tasks_mm_cpumask(cpu); + + return 0; +} +#else /* ... !CONFIG_HOTPLUG_CPU */ +int native_cpu_disable(unsigned int cpu) +{ + return -ENOSYS; +} + +void native_cpu_die(unsigned int cpu) +{ + /* We said "no" in __cpu_disable */ + BUG(); +} + +void native_play_dead(void) +{ + BUG(); +} +#endif + +asmlinkage void start_secondary(void) +{ + unsigned int cpu = smp_processor_id(); + struct mm_struct *mm = &init_mm; + + enable_mmu(); + mmgrab(mm); + mmget(mm); + current->active_mm = mm; +#ifdef CONFIG_MMU + enter_lazy_tlb(mm, current); + local_flush_tlb_all(); +#endif + + per_cpu_trap_init(); + + preempt_disable(); + + notify_cpu_starting(cpu); + + local_irq_enable(); + + calibrate_delay(); + + smp_store_cpu_info(cpu); + + set_cpu_online(cpu, true); + per_cpu(cpu_state, cpu) = CPU_ONLINE; + + cpu_startup_entry(CPUHP_AP_ONLINE_IDLE); +} + +extern struct { + unsigned long sp; + unsigned long bss_start; + unsigned long bss_end; + void *start_kernel_fn; + void *cpu_init_fn; + void *thread_info; +} stack_start; + +int __cpu_up(unsigned int cpu, struct task_struct *tsk) +{ + unsigned long timeout; + + per_cpu(cpu_state, cpu) = CPU_UP_PREPARE; + + /* Fill in data in head.S for secondary cpus */ + stack_start.sp = tsk->thread.sp; + stack_start.thread_info = tsk->stack; + stack_start.bss_start = 0; /* don't clear bss for secondary cpus */ + stack_start.start_kernel_fn = start_secondary; + + flush_icache_range((unsigned long)&stack_start, + (unsigned long)&stack_start + sizeof(stack_start)); + wmb(); + + mp_ops->start_cpu(cpu, (unsigned long)_stext); + + timeout = jiffies + HZ; + while (time_before(jiffies, timeout)) { + if (cpu_online(cpu)) + break; + + udelay(10); + barrier(); + } + + if (cpu_online(cpu)) + return 0; + + return -ENOENT; +} + +void __init smp_cpus_done(unsigned int max_cpus) +{ + unsigned long bogosum = 0; + int cpu; + + for_each_online_cpu(cpu) + bogosum += cpu_data[cpu].loops_per_jiffy; + + printk(KERN_INFO "SMP: Total of %d processors activated " + "(%lu.%02lu BogoMIPS).\n", num_online_cpus(), + bogosum / (500000/HZ), + (bogosum / (5000/HZ)) % 100); +} + +void smp_send_reschedule(int cpu) +{ + mp_ops->send_ipi(cpu, SMP_MSG_RESCHEDULE); +} + +void smp_send_stop(void) +{ + smp_call_function(stop_this_cpu, 0, 0); +} + +void arch_send_call_function_ipi_mask(const struct cpumask *mask) +{ + int cpu; + + for_each_cpu(cpu, mask) + mp_ops->send_ipi(cpu, SMP_MSG_FUNCTION); +} + +void arch_send_call_function_single_ipi(int cpu) +{ + mp_ops->send_ipi(cpu, SMP_MSG_FUNCTION_SINGLE); +} + +#ifdef CONFIG_GENERIC_CLOCKEVENTS_BROADCAST +void tick_broadcast(const struct cpumask *mask) +{ + int cpu; + + for_each_cpu(cpu, mask) + mp_ops->send_ipi(cpu, SMP_MSG_TIMER); +} + +static void ipi_timer(void) +{ + irq_enter(); + tick_receive_broadcast(); + irq_exit(); +} +#endif + +void smp_message_recv(unsigned int msg) +{ + switch (msg) { + case SMP_MSG_FUNCTION: + generic_smp_call_function_interrupt(); + break; + case SMP_MSG_RESCHEDULE: + scheduler_ipi(); + break; + case SMP_MSG_FUNCTION_SINGLE: + generic_smp_call_function_single_interrupt(); + break; +#ifdef CONFIG_GENERIC_CLOCKEVENTS_BROADCAST + case SMP_MSG_TIMER: + ipi_timer(); + break; +#endif + default: + printk(KERN_WARNING "SMP %d: %s(): unknown IPI %d\n", + smp_processor_id(), __func__, msg); + break; + } +} + +/* Not really SMP stuff ... */ +int setup_profiling_timer(unsigned int multiplier) +{ + return 0; +} + +#ifdef CONFIG_MMU + +static void flush_tlb_all_ipi(void *info) +{ + local_flush_tlb_all(); +} + +void flush_tlb_all(void) +{ + on_each_cpu(flush_tlb_all_ipi, 0, 1); +} + +static void flush_tlb_mm_ipi(void *mm) +{ + local_flush_tlb_mm((struct mm_struct *)mm); +} + +/* + * The following tlb flush calls are invoked when old translations are + * being torn down, or pte attributes are changing. For single threaded + * address spaces, a new context is obtained on the current cpu, and tlb + * context on other cpus are invalidated to force a new context allocation + * at switch_mm time, should the mm ever be used on other cpus. For + * multithreaded address spaces, intercpu interrupts have to be sent. + * Another case where intercpu interrupts are required is when the target + * mm might be active on another cpu (eg debuggers doing the flushes on + * behalf of debugees, kswapd stealing pages from another process etc). + * Kanoj 07/00. + */ +void flush_tlb_mm(struct mm_struct *mm) +{ + preempt_disable(); + + if ((atomic_read(&mm->mm_users) != 1) || (current->mm != mm)) { + smp_call_function(flush_tlb_mm_ipi, (void *)mm, 1); + } else { + int i; + for_each_online_cpu(i) + if (smp_processor_id() != i) + cpu_context(i, mm) = 0; + } + local_flush_tlb_mm(mm); + + preempt_enable(); +} + +struct flush_tlb_data { + struct vm_area_struct *vma; + unsigned long addr1; + unsigned long addr2; +}; + +static void flush_tlb_range_ipi(void *info) +{ + struct flush_tlb_data *fd = (struct flush_tlb_data *)info; + + local_flush_tlb_range(fd->vma, fd->addr1, fd->addr2); +} + +void flush_tlb_range(struct vm_area_struct *vma, + unsigned long start, unsigned long end) +{ + struct mm_struct *mm = vma->vm_mm; + + preempt_disable(); + if ((atomic_read(&mm->mm_users) != 1) || (current->mm != mm)) { + struct flush_tlb_data fd; + + fd.vma = vma; + fd.addr1 = start; + fd.addr2 = end; + smp_call_function(flush_tlb_range_ipi, (void *)&fd, 1); + } else { + int i; + for_each_online_cpu(i) + if (smp_processor_id() != i) + cpu_context(i, mm) = 0; + } + local_flush_tlb_range(vma, start, end); + preempt_enable(); +} + +static void flush_tlb_kernel_range_ipi(void *info) +{ + struct flush_tlb_data *fd = (struct flush_tlb_data *)info; + + local_flush_tlb_kernel_range(fd->addr1, fd->addr2); +} + +void flush_tlb_kernel_range(unsigned long start, unsigned long end) +{ + struct flush_tlb_data fd; + + fd.addr1 = start; + fd.addr2 = end; + on_each_cpu(flush_tlb_kernel_range_ipi, (void *)&fd, 1); +} + +static void flush_tlb_page_ipi(void *info) +{ + struct flush_tlb_data *fd = (struct flush_tlb_data *)info; + + local_flush_tlb_page(fd->vma, fd->addr1); +} + +void flush_tlb_page(struct vm_area_struct *vma, unsigned long page) +{ + preempt_disable(); + if ((atomic_read(&vma->vm_mm->mm_users) != 1) || + (current->mm != vma->vm_mm)) { + struct flush_tlb_data fd; + + fd.vma = vma; + fd.addr1 = page; + smp_call_function(flush_tlb_page_ipi, (void *)&fd, 1); + } else { + int i; + for_each_online_cpu(i) + if (smp_processor_id() != i) + cpu_context(i, vma->vm_mm) = 0; + } + local_flush_tlb_page(vma, page); + preempt_enable(); +} + +static void flush_tlb_one_ipi(void *info) +{ + struct flush_tlb_data *fd = (struct flush_tlb_data *)info; + local_flush_tlb_one(fd->addr1, fd->addr2); +} + +void flush_tlb_one(unsigned long asid, unsigned long vaddr) +{ + struct flush_tlb_data fd; + + fd.addr1 = asid; + fd.addr2 = vaddr; + + smp_call_function(flush_tlb_one_ipi, (void *)&fd, 1); + local_flush_tlb_one(asid, vaddr); +} + +#endif |