summaryrefslogtreecommitdiffstats
path: root/arch/sh/kernel/smp.c
diff options
context:
space:
mode:
Diffstat (limited to 'arch/sh/kernel/smp.c')
-rw-r--r--arch/sh/kernel/smp.c471
1 files changed, 471 insertions, 0 deletions
diff --git a/arch/sh/kernel/smp.c b/arch/sh/kernel/smp.c
new file mode 100644
index 000000000..65924d9ec
--- /dev/null
+++ b/arch/sh/kernel/smp.c
@@ -0,0 +1,471 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * arch/sh/kernel/smp.c
+ *
+ * SMP support for the SuperH processors.
+ *
+ * Copyright (C) 2002 - 2010 Paul Mundt
+ * Copyright (C) 2006 - 2007 Akio Idehara
+ */
+#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();
+
+ 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