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 0000000000..5cf35a774d
--- /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 arch_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