[deliverable/linux.git] / arch / powerpc / kernel / smp.c

/*
 * SMP support for ppc.
 *
 * Written by Cort Dougan (cort@cs.nmt.edu) borrowing a great
 * deal of code from the sparc and intel versions.
 *
 * Copyright (C) 1999 Cort Dougan <cort@cs.nmt.edu>
 *
 * PowerPC-64 Support added by Dave Engebretsen, Peter Bergner, and
 * Mike Corrigan {engebret|bergner|mikec}@us.ibm.com
 *
 *      This program is free software; you can redistribute it and/or
 *      modify it under the terms of the GNU General Public License
 *      as published by the Free Software Foundation; either version
 *      2 of the License, or (at your option) any later version.
 */

#undef DEBUG

#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/sched.h>
#include <linux/smp.h>
#include <linux/interrupt.h>
#include <linux/delay.h>
#include <linux/init.h>
#include <linux/spinlock.h>
#include <linux/cache.h>
#include <linux/err.h>
#include <linux/sysdev.h>
#include <linux/cpu.h>
#include <linux/notifier.h>
#include <linux/topology.h>

#include <asm/ptrace.h>
#include <asm/atomic.h>
#include <asm/irq.h>
#include <asm/page.h>
#include <asm/pgtable.h>
#include <asm/prom.h>
#include <asm/smp.h>
#include <asm/time.h>
#include <asm/machdep.h>
#include <asm/cputhreads.h>
#include <asm/cputable.h>
#include <asm/system.h>
#include <asm/mpic.h>
#include <asm/vdso_datapage.h>
#ifdef CONFIG_PPC64
#include <asm/paca.h>
#endif

#ifdef DEBUG
#include <asm/udbg.h>
#define DBG(fmt...) udbg_printf(fmt)
#else
#define DBG(fmt...)
#endif

struct thread_info *secondary_ti;

cpumask_t cpu_possible_map = CPU_MASK_NONE;
cpumask_t cpu_online_map = CPU_MASK_NONE;
DEFINE_PER_CPU(cpumask_t, cpu_sibling_map) = CPU_MASK_NONE;
DEFINE_PER_CPU(cpumask_t, cpu_core_map) = CPU_MASK_NONE;

EXPORT_SYMBOL(cpu_online_map);
EXPORT_SYMBOL(cpu_possible_map);
EXPORT_PER_CPU_SYMBOL(cpu_sibling_map);
EXPORT_PER_CPU_SYMBOL(cpu_core_map);

/* SMP operations for this machine */
struct smp_ops_t *smp_ops;

static volatile unsigned int cpu_callin_map[NR_CPUS];

int smt_enabled_at_boot = 1;

static void (*crash_ipi_function_ptr)(struct pt_regs *) = NULL;

#ifdef CONFIG_PPC64
void __devinit smp_generic_kick_cpu(int nr)
{
	BUG_ON(nr < 0 || nr >= NR_CPUS);

	/*
	 * The processor is currently spinning, waiting for the
	 * cpu_start field to become non-zero After we set cpu_start,
	 * the processor will continue on to secondary_start
	 */
	paca[nr].cpu_start = 1;
	smp_mb();
}
#endif

void smp_message_recv(int msg)
{
	switch(msg) {
	case PPC_MSG_CALL_FUNCTION:
		generic_smp_call_function_interrupt();
		break;
	case PPC_MSG_RESCHEDULE:
		/* we notice need_resched on exit */
		break;
	case PPC_MSG_CALL_FUNC_SINGLE:
		generic_smp_call_function_single_interrupt();
		break;
	case PPC_MSG_DEBUGGER_BREAK:
		if (crash_ipi_function_ptr) {
			crash_ipi_function_ptr(get_irq_regs());
			break;
		}
#ifdef CONFIG_DEBUGGER
		debugger_ipi(get_irq_regs());
		break;
#endif /* CONFIG_DEBUGGER */
		/* FALLTHROUGH */
	default:
		printk("SMP %d: smp_message_recv(): unknown msg %d\n",
		       smp_processor_id(), msg);
		break;
	}
}

static irqreturn_t call_function_action(int irq, void *data)
{
	generic_smp_call_function_interrupt();
	return IRQ_HANDLED;
}

static irqreturn_t reschedule_action(int irq, void *data)
{
	/* we just need the return path side effect of checking need_resched */
	return IRQ_HANDLED;
}

static irqreturn_t call_function_single_action(int irq, void *data)
{
	generic_smp_call_function_single_interrupt();
	return IRQ_HANDLED;
}

static irqreturn_t debug_ipi_action(int irq, void *data)
{
	smp_message_recv(PPC_MSG_DEBUGGER_BREAK);
	return IRQ_HANDLED;
}

static irq_handler_t smp_ipi_action[] = {
	[PPC_MSG_CALL_FUNCTION] =  call_function_action,
	[PPC_MSG_RESCHEDULE] = reschedule_action,
	[PPC_MSG_CALL_FUNC_SINGLE] = call_function_single_action,
	[PPC_MSG_DEBUGGER_BREAK] = debug_ipi_action,
};

const char *smp_ipi_name[] = {
	[PPC_MSG_CALL_FUNCTION] =  "ipi call function",
	[PPC_MSG_RESCHEDULE] = "ipi reschedule",
	[PPC_MSG_CALL_FUNC_SINGLE] = "ipi call function single",
	[PPC_MSG_DEBUGGER_BREAK] = "ipi debugger",
};

/* optional function to request ipi, for controllers with >= 4 ipis */
int smp_request_message_ipi(int virq, int msg)
{
	int err;

	if (msg < 0 || msg > PPC_MSG_DEBUGGER_BREAK) {
		return -EINVAL;
	}
#if !defined(CONFIG_DEBUGGER) && !defined(CONFIG_KEXEC)
	if (msg == PPC_MSG_DEBUGGER_BREAK) {
		return 1;
	}
#endif
	err = request_irq(virq, smp_ipi_action[msg], IRQF_DISABLED|IRQF_PERCPU,
			  smp_ipi_name[msg], 0);
	WARN(err < 0, "unable to request_irq %d for %s (rc %d)\n",
		virq, smp_ipi_name[msg], err);

	return err;
}

void smp_send_reschedule(int cpu)
{
	if (likely(smp_ops))
		smp_ops->message_pass(cpu, PPC_MSG_RESCHEDULE);
}

void arch_send_call_function_single_ipi(int cpu)
{
	smp_ops->message_pass(cpu, PPC_MSG_CALL_FUNC_SINGLE);
}

void arch_send_call_function_ipi(cpumask_t mask)
{
	unsigned int cpu;

	for_each_cpu_mask(cpu, mask)
		smp_ops->message_pass(cpu, PPC_MSG_CALL_FUNCTION);
}

#ifdef CONFIG_DEBUGGER
void smp_send_debugger_break(int cpu)
{
	if (likely(smp_ops))
		smp_ops->message_pass(cpu, PPC_MSG_DEBUGGER_BREAK);
}
#endif

#ifdef CONFIG_KEXEC
void crash_send_ipi(void (*crash_ipi_callback)(struct pt_regs *))
{
	crash_ipi_function_ptr = crash_ipi_callback;
	if (crash_ipi_callback && smp_ops) {
		mb();
		smp_ops->message_pass(MSG_ALL_BUT_SELF, PPC_MSG_DEBUGGER_BREAK);
	}
}
#endif

static void stop_this_cpu(void *dummy)
{
	local_irq_disable();
	while (1)
		;
}

void smp_send_stop(void)
{
	smp_call_function(stop_this_cpu, NULL, 0);
}

struct thread_info *current_set[NR_CPUS];

static void __devinit smp_store_cpu_info(int id)
{
	per_cpu(pvr, id) = mfspr(SPRN_PVR);
}

static void __init smp_create_idle(unsigned int cpu)
{
	struct task_struct *p;

	/* create a process for the processor */
	p = fork_idle(cpu);
	if (IS_ERR(p))
		panic("failed fork for CPU %u: %li", cpu, PTR_ERR(p));
#ifdef CONFIG_PPC64
	paca[cpu].__current = p;
	paca[cpu].kstack = (unsigned long) task_thread_info(p)
		+ THREAD_SIZE - STACK_FRAME_OVERHEAD;
#endif
	current_set[cpu] = task_thread_info(p);
	task_thread_info(p)->cpu = cpu;
}

void __init smp_prepare_cpus(unsigned int max_cpus)
{
	unsigned int cpu;

	DBG("smp_prepare_cpus\n");

	/* 
	 * setup_cpu may need to be called on the boot cpu. We havent
	 * spun any cpus up but lets be paranoid.
	 */
	BUG_ON(boot_cpuid != smp_processor_id());

	/* Fixup boot cpu */
	smp_store_cpu_info(boot_cpuid);
	cpu_callin_map[boot_cpuid] = 1;

	if (smp_ops)
		max_cpus = smp_ops->probe();
	else
		max_cpus = 1;
 
	smp_space_timers(max_cpus);

	for_each_possible_cpu(cpu)
		if (cpu != boot_cpuid)
			smp_create_idle(cpu);
}

void __devinit smp_prepare_boot_cpu(void)
{
	BUG_ON(smp_processor_id() != boot_cpuid);

	cpu_set(boot_cpuid, cpu_online_map);
	cpu_set(boot_cpuid, per_cpu(cpu_sibling_map, boot_cpuid));
	cpu_set(boot_cpuid, per_cpu(cpu_core_map, boot_cpuid));
#ifdef CONFIG_PPC64
	paca[boot_cpuid].__current = current;
#endif
	current_set[boot_cpuid] = task_thread_info(current);
}

#ifdef CONFIG_HOTPLUG_CPU
/* State of each CPU during hotplug phases */
DEFINE_PER_CPU(int, cpu_state) = { 0 };

int generic_cpu_disable(void)
{
	unsigned int cpu = smp_processor_id();

	if (cpu == boot_cpuid)
		return -EBUSY;

	cpu_clear(cpu, cpu_online_map);
#ifdef CONFIG_PPC64
	vdso_data->processorCount--;
	fixup_irqs(cpu_online_map);
#endif
	return 0;
}

int generic_cpu_enable(unsigned int cpu)
{
	/* Do the normal bootup if we haven't
	 * already bootstrapped. */
	if (system_state != SYSTEM_RUNNING)
		return -ENOSYS;

	/* get the target out of it's holding state */
	per_cpu(cpu_state, cpu) = CPU_UP_PREPARE;
	smp_wmb();

	while (!cpu_online(cpu))
		cpu_relax();

#ifdef CONFIG_PPC64
	fixup_irqs(cpu_online_map);
	/* counter the irq disable in fixup_irqs */
	local_irq_enable();
#endif
	return 0;
}

void generic_cpu_die(unsigned int cpu)
{
	int i;

	for (i = 0; i < 100; i++) {
		smp_rmb();
		if (per_cpu(cpu_state, cpu) == CPU_DEAD)
			return;
		msleep(100);
	}
	printk(KERN_ERR "CPU%d didn't die...\n", cpu);
}

void generic_mach_cpu_die(void)
{
	unsigned int cpu;

	local_irq_disable();
	cpu = smp_processor_id();
	printk(KERN_DEBUG "CPU%d offline\n", cpu);
	__get_cpu_var(cpu_state) = CPU_DEAD;
	smp_wmb();
	while (__get_cpu_var(cpu_state) != CPU_UP_PREPARE)
		cpu_relax();
	cpu_set(cpu, cpu_online_map);
	local_irq_enable();
}
#endif

static int __devinit cpu_enable(unsigned int cpu)
{
	if (smp_ops && smp_ops->cpu_enable)
		return smp_ops->cpu_enable(cpu);

	return -ENOSYS;
}

int __cpuinit __cpu_up(unsigned int cpu)
{
	int c;

	secondary_ti = current_set[cpu];
	if (!cpu_enable(cpu))
		return 0;

	if (smp_ops == NULL ||
	    (smp_ops->cpu_bootable && !smp_ops->cpu_bootable(cpu)))
		return -EINVAL;

	/* Make sure callin-map entry is 0 (can be leftover a CPU
	 * hotplug
	 */
	cpu_callin_map[cpu] = 0;

	/* The information for processor bringup must
	 * be written out to main store before we release
	 * the processor.
	 */
	smp_mb();

	/* wake up cpus */
	DBG("smp: kicking cpu %d\n", cpu);
	smp_ops->kick_cpu(cpu);

	/*
	 * wait to see if the cpu made a callin (is actually up).
	 * use this value that I found through experimentation.
	 * -- Cort
	 */
	if (system_state < SYSTEM_RUNNING)
		for (c = 50000; c && !cpu_callin_map[cpu]; c--)
			udelay(100);
#ifdef CONFIG_HOTPLUG_CPU
	else
		/*
		 * CPUs can take much longer to come up in the
		 * hotplug case.  Wait five seconds.
		 */
		for (c = 25; c && !cpu_callin_map[cpu]; c--) {
			msleep(200);
		}
#endif

	if (!cpu_callin_map[cpu]) {
		printk("Processor %u is stuck.\n", cpu);
		return -ENOENT;
	}

	printk("Processor %u found.\n", cpu);

	if (smp_ops->give_timebase)
		smp_ops->give_timebase();

	/* Wait until cpu puts itself in the online map */
	while (!cpu_online(cpu))
		cpu_relax();

	return 0;
}

/* Return the value of the reg property corresponding to the given
 * logical cpu.
 */
int cpu_to_core_id(int cpu)
{
	struct device_node *np;
	const int *reg;
	int id = -1;

	np = of_get_cpu_node(cpu, NULL);
	if (!np)
		goto out;

	reg = of_get_property(np, "reg", NULL);
	if (!reg)
		goto out;

	id = *reg;
out:
	of_node_put(np);
	return id;
}

/* Must be called when no change can occur to cpu_present_map,
 * i.e. during cpu online or offline.
 */
static struct device_node *cpu_to_l2cache(int cpu)
{
	struct device_node *np;
	struct device_node *cache;

	if (!cpu_present(cpu))
		return NULL;

	np = of_get_cpu_node(cpu, NULL);
	if (np == NULL)
		return NULL;

	cache = of_find_next_cache_node(np);

	of_node_put(np);

	return cache;
}

/* Activate a secondary processor. */
int __devinit start_secondary(void *unused)
{
	unsigned int cpu = smp_processor_id();
	struct device_node *l2_cache;
	int i, base;

	atomic_inc(&init_mm.mm_count);
	current->active_mm = &init_mm;

	smp_store_cpu_info(cpu);
	set_dec(tb_ticks_per_jiffy);
	preempt_disable();
	cpu_callin_map[cpu] = 1;

	smp_ops->setup_cpu(cpu);
	if (smp_ops->take_timebase)
		smp_ops->take_timebase();

	if (system_state > SYSTEM_BOOTING)
		snapshot_timebase();

	secondary_cpu_time_init();

	ipi_call_lock();
	notify_cpu_starting(cpu);
	cpu_set(cpu, cpu_online_map);
	/* Update sibling maps */
	base = cpu_first_thread_in_core(cpu);
	for (i = 0; i < threads_per_core; i++) {
		if (cpu_is_offline(base + i))
			continue;
		cpu_set(cpu, per_cpu(cpu_sibling_map, base + i));
		cpu_set(base + i, per_cpu(cpu_sibling_map, cpu));

		/* cpu_core_map should be a superset of
		 * cpu_sibling_map even if we don't have cache
		 * information, so update the former here, too.
		 */
		cpu_set(cpu, per_cpu(cpu_core_map, base +i));
		cpu_set(base + i, per_cpu(cpu_core_map, cpu));
	}
	l2_cache = cpu_to_l2cache(cpu);
	for_each_online_cpu(i) {
		struct device_node *np = cpu_to_l2cache(i);
		if (!np)
			continue;
		if (np == l2_cache) {
			cpu_set(cpu, per_cpu(cpu_core_map, i));
			cpu_set(i, per_cpu(cpu_core_map, cpu));
		}
		of_node_put(np);
	}
	of_node_put(l2_cache);
	ipi_call_unlock();

	local_irq_enable();

	cpu_idle();
	return 0;
}

int setup_profiling_timer(unsigned int multiplier)
{
	return 0;
}

void __init smp_cpus_done(unsigned int max_cpus)
{
	cpumask_t old_mask;

	/* We want the setup_cpu() here to be called from CPU 0, but our
	 * init thread may have been "borrowed" by another CPU in the meantime
	 * se we pin us down to CPU 0 for a short while
	 */
	old_mask = current->cpus_allowed;
	set_cpus_allowed(current, cpumask_of_cpu(boot_cpuid));
	
	if (smp_ops)
		smp_ops->setup_cpu(boot_cpuid);

	set_cpus_allowed(current, old_mask);

	snapshot_timebases();

	dump_numa_cpu_topology();
}

#ifdef CONFIG_HOTPLUG_CPU
int __cpu_disable(void)
{
	struct device_node *l2_cache;
	int cpu = smp_processor_id();
	int base, i;
	int err;

	if (!smp_ops->cpu_disable)
		return -ENOSYS;

	err = smp_ops->cpu_disable();
	if (err)
		return err;

	/* Update sibling maps */
	base = cpu_first_thread_in_core(cpu);
	for (i = 0; i < threads_per_core; i++) {
		cpu_clear(cpu, per_cpu(cpu_sibling_map, base + i));
		cpu_clear(base + i, per_cpu(cpu_sibling_map, cpu));
		cpu_clear(cpu, per_cpu(cpu_core_map, base +i));
		cpu_clear(base + i, per_cpu(cpu_core_map, cpu));
	}

	l2_cache = cpu_to_l2cache(cpu);
	for_each_present_cpu(i) {
		struct device_node *np = cpu_to_l2cache(i);
		if (!np)
			continue;
		if (np == l2_cache) {
			cpu_clear(cpu, per_cpu(cpu_core_map, i));
			cpu_clear(i, per_cpu(cpu_core_map, cpu));
		}
		of_node_put(np);
	}
	of_node_put(l2_cache);


	return 0;
}

void __cpu_die(unsigned int cpu)
{
	if (smp_ops->cpu_die)
		smp_ops->cpu_die(cpu);
}
#endif
Commit	Line	Data
1da177e4 LT	1	/*
	2	* SMP support for ppc.
	3	*
	4	* Written by Cort Dougan (cort@cs.nmt.edu) borrowing a great
	5	* deal of code from the sparc and intel versions.
	6	*
	7	* Copyright (C) 1999 Cort Dougan <cort@cs.nmt.edu>
	8	*
	9	* PowerPC-64 Support added by Dave Engebretsen, Peter Bergner, and
	10	* Mike Corrigan {engebret\|bergner\|mikec}@us.ibm.com
	11	*
	12	* This program is free software; you can redistribute it and/or
	13	* modify it under the terms of the GNU General Public License
	14	* as published by the Free Software Foundation; either version
	15	* 2 of the License, or (at your option) any later version.
	16	*/
	17
	18	#undef DEBUG
	19
1da177e4 LT	20	#include <linux/kernel.h>
	21	#include <linux/module.h>
	22	#include <linux/sched.h>
	23	#include <linux/smp.h>
	24	#include <linux/interrupt.h>
	25	#include <linux/delay.h>
	26	#include <linux/init.h>
	27	#include <linux/spinlock.h>
	28	#include <linux/cache.h>
	29	#include <linux/err.h>
	30	#include <linux/sysdev.h>
	31	#include <linux/cpu.h>
	32	#include <linux/notifier.h>
4b703a23	33	#include <linux/topology.h>
1da177e4 LT	34
	35	#include <asm/ptrace.h>
	36	#include <asm/atomic.h>
	37	#include <asm/irq.h>
	38	#include <asm/page.h>
	39	#include <asm/pgtable.h>
	40	#include <asm/prom.h>
	41	#include <asm/smp.h>
1da177e4 LT	42	#include <asm/time.h>
1da177e4 LT	43	#include <asm/machdep.h>
e2075f79	44	#include <asm/cputhreads.h>
1da177e4 LT	45	#include <asm/cputable.h>
1da177e4 LT	46	#include <asm/system.h>
bbeb3f4c	47	#include <asm/mpic.h>
a7f290da	48	#include <asm/vdso_datapage.h>
5ad57078 PM	49	#ifdef CONFIG_PPC64
	50	#include <asm/paca.h>
	51	#endif
	52
1da177e4	53	#ifdef DEBUG
f9e4ec57	54	#include <asm/udbg.h>
1da177e4 LT	55	#define DBG(fmt...) udbg_printf(fmt)
	56	#else
	57	#define DBG(fmt...)
	58	#endif
	59
f9e4ec57 ME	60	struct thread_info *secondary_ti;
f9e4ec57 ME	61
1da177e4 LT	62	cpumask_t cpu_possible_map = CPU_MASK_NONE;
1da177e4 LT	63	cpumask_t cpu_online_map = CPU_MASK_NONE;
d5a7430d	64	DEFINE_PER_CPU(cpumask_t, cpu_sibling_map) = CPU_MASK_NONE;
440a0857	65	DEFINE_PER_CPU(cpumask_t, cpu_core_map) = CPU_MASK_NONE;
1da177e4 LT	66
	67	EXPORT_SYMBOL(cpu_online_map);
	68	EXPORT_SYMBOL(cpu_possible_map);
d5a7430d	69	EXPORT_PER_CPU_SYMBOL(cpu_sibling_map);
440a0857	70	EXPORT_PER_CPU_SYMBOL(cpu_core_map);
1da177e4	71
5ad57078	72	/* SMP operations for this machine */
1da177e4 LT	73	struct smp_ops_t *smp_ops;
	74
	75	static volatile unsigned int cpu_callin_map[NR_CPUS];
	76
1da177e4 LT	77	int smt_enabled_at_boot = 1;
1da177e4 LT	78
cc532915 ME	79	static void (crash_ipi_function_ptr)(struct pt_regs ) = NULL;
cc532915 ME	80
5ad57078	81	#ifdef CONFIG_PPC64
1da177e4 LT	82	void __devinit smp_generic_kick_cpu(int nr)
	83	{
	84	BUG_ON(nr < 0 \|\| nr >= NR_CPUS);
	85
	86	/*
	87	* The processor is currently spinning, waiting for the
	88	* cpu_start field to become non-zero After we set cpu_start,
	89	* the processor will continue on to secondary_start
	90	*/
	91	paca[nr].cpu_start = 1;
0d8d4d42	92	smp_mb();
1da177e4	93	}
5ad57078	94	#endif
1da177e4	95
7d12e780	96	void smp_message_recv(int msg)
1da177e4 LT	97	{
	98	switch(msg) {
	99	case PPC_MSG_CALL_FUNCTION:
b7d7a240	100	generic_smp_call_function_interrupt();
1da177e4	101	break;
5ad57078	102	case PPC_MSG_RESCHEDULE:
22d660ff	103	/* we notice need_resched on exit */
1da177e4	104	break;
b7d7a240 JA	105	case PPC_MSG_CALL_FUNC_SINGLE:
	106	generic_smp_call_function_single_interrupt();
	107	break;
1da177e4	108	case PPC_MSG_DEBUGGER_BREAK:
cc532915	109	if (crash_ipi_function_ptr) {
7d12e780	110	crash_ipi_function_ptr(get_irq_regs());
cc532915 ME	111	break;
	112	}
	113	#ifdef CONFIG_DEBUGGER
7d12e780	114	debugger_ipi(get_irq_regs());
1da177e4	115	break;
cc532915 ME	116	#endif /* CONFIG_DEBUGGER */
cc532915 ME	117	/* FALLTHROUGH */
1da177e4 LT	118	default:
	119	printk("SMP %d: smp_message_recv(): unknown msg %d\n",
	120	smp_processor_id(), msg);
	121	break;
	122	}
	123	}
	124
25ddd738 MM	125	static irqreturn_t call_function_action(int irq, void *data)
	126	{
	127	generic_smp_call_function_interrupt();
	128	return IRQ_HANDLED;
	129	}
	130
	131	static irqreturn_t reschedule_action(int irq, void *data)
	132	{
	133	/* we just need the return path side effect of checking need_resched */
	134	return IRQ_HANDLED;
	135	}
	136
	137	static irqreturn_t call_function_single_action(int irq, void *data)
	138	{
	139	generic_smp_call_function_single_interrupt();
	140	return IRQ_HANDLED;
	141	}
	142
	143	static irqreturn_t debug_ipi_action(int irq, void *data)
	144	{
	145	smp_message_recv(PPC_MSG_DEBUGGER_BREAK);
	146	return IRQ_HANDLED;
	147	}
	148
	149	static irq_handler_t smp_ipi_action[] = {
	150	[PPC_MSG_CALL_FUNCTION] = call_function_action,
	151	[PPC_MSG_RESCHEDULE] = reschedule_action,
	152	[PPC_MSG_CALL_FUNC_SINGLE] = call_function_single_action,
	153	[PPC_MSG_DEBUGGER_BREAK] = debug_ipi_action,
	154	};
	155
	156	const char *smp_ipi_name[] = {
	157	[PPC_MSG_CALL_FUNCTION] = "ipi call function",
	158	[PPC_MSG_RESCHEDULE] = "ipi reschedule",
	159	[PPC_MSG_CALL_FUNC_SINGLE] = "ipi call function single",
	160	[PPC_MSG_DEBUGGER_BREAK] = "ipi debugger",
	161	};
	162
	163	/* optional function to request ipi, for controllers with >= 4 ipis */
	164	int smp_request_message_ipi(int virq, int msg)
	165	{
	166	int err;
	167
	168	if (msg < 0 \|\| msg > PPC_MSG_DEBUGGER_BREAK) {
	169	return -EINVAL;
	170	}
	171	#if !defined(CONFIG_DEBUGGER) && !defined(CONFIG_KEXEC)
	172	if (msg == PPC_MSG_DEBUGGER_BREAK) {
	173	return 1;
	174	}
	175	#endif
	176	err = request_irq(virq, smp_ipi_action[msg], IRQF_DISABLED\|IRQF_PERCPU,
	177	smp_ipi_name[msg], 0);
	178	WARN(err < 0, "unable to request_irq %d for %s (rc %d)\n",
	179	virq, smp_ipi_name[msg], err);
	180
	181	return err;
	182	}
	183
1da177e4 LT	184	void smp_send_reschedule(int cpu)
1da177e4 LT	185	{
8cffc6ac BH	186	if (likely(smp_ops))
8cffc6ac BH	187	smp_ops->message_pass(cpu, PPC_MSG_RESCHEDULE);
1da177e4 LT	188	}
1da177e4 LT	189
b7d7a240 JA	190	void arch_send_call_function_single_ipi(int cpu)
	191	{
	192	smp_ops->message_pass(cpu, PPC_MSG_CALL_FUNC_SINGLE);
	193	}
	194
	195	void arch_send_call_function_ipi(cpumask_t mask)
	196	{
	197	unsigned int cpu;
	198
	199	for_each_cpu_mask(cpu, mask)
	200	smp_ops->message_pass(cpu, PPC_MSG_CALL_FUNCTION);
	201	}
	202
1da177e4 LT	203	#ifdef CONFIG_DEBUGGER
	204	void smp_send_debugger_break(int cpu)
	205	{
8cffc6ac BH	206	if (likely(smp_ops))
8cffc6ac BH	207	smp_ops->message_pass(cpu, PPC_MSG_DEBUGGER_BREAK);
1da177e4 LT	208	}
	209	#endif
	210
cc532915 ME	211	#ifdef CONFIG_KEXEC
	212	void crash_send_ipi(void (crash_ipi_callback)(struct pt_regs ))
	213	{
	214	crash_ipi_function_ptr = crash_ipi_callback;
8cffc6ac	215	if (crash_ipi_callback && smp_ops) {
cc532915 ME	216	mb();
	217	smp_ops->message_pass(MSG_ALL_BUT_SELF, PPC_MSG_DEBUGGER_BREAK);
	218	}
	219	}
	220	#endif
	221
1da177e4 LT	222	static void stop_this_cpu(void *dummy)
	223	{
	224	local_irq_disable();
	225	while (1)
	226	;
	227	}
	228
8fd7675c SS	229	void smp_send_stop(void)
8fd7675c SS	230	{
8691e5a8	231	smp_call_function(stop_this_cpu, NULL, 0);
1da177e4 LT	232	}
1da177e4 LT	233
1da177e4 LT	234	struct thread_info *current_set[NR_CPUS];
1da177e4 LT	235
1da177e4 LT	236	static void __devinit smp_store_cpu_info(int id)
	237	{
	238	per_cpu(pvr, id) = mfspr(SPRN_PVR);
	239	}
	240
	241	static void __init smp_create_idle(unsigned int cpu)
	242	{
	243	struct task_struct *p;
	244
	245	/* create a process for the processor */
	246	p = fork_idle(cpu);
	247	if (IS_ERR(p))
	248	panic("failed fork for CPU %u: %li", cpu, PTR_ERR(p));
5ad57078	249	#ifdef CONFIG_PPC64
1da177e4	250	paca[cpu].__current = p;
3b575064 PM	251	paca[cpu].kstack = (unsigned long) task_thread_info(p)
3b575064 PM	252	+ THREAD_SIZE - STACK_FRAME_OVERHEAD;
5ad57078	253	#endif
b5e2fc1c AV	254	current_set[cpu] = task_thread_info(p);
b5e2fc1c AV	255	task_thread_info(p)->cpu = cpu;
1da177e4 LT	256	}
	257
	258	void __init smp_prepare_cpus(unsigned int max_cpus)
	259	{
	260	unsigned int cpu;
	261
	262	DBG("smp_prepare_cpus\n");
	263
	264	/*
	265	* setup_cpu may need to be called on the boot cpu. We havent
	266	* spun any cpus up but lets be paranoid.
	267	*/
	268	BUG_ON(boot_cpuid != smp_processor_id());
	269
	270	/* Fixup boot cpu */
	271	smp_store_cpu_info(boot_cpuid);
	272	cpu_callin_map[boot_cpuid] = 1;
	273
8cffc6ac BH	274	if (smp_ops)
	275	max_cpus = smp_ops->probe();
	276	else
	277	max_cpus = 1;
1da177e4 LT	278
	279	smp_space_timers(max_cpus);
	280
0e551954	281	for_each_possible_cpu(cpu)
1da177e4 LT	282	if (cpu != boot_cpuid)
	283	smp_create_idle(cpu);
	284	}
	285
	286	void __devinit smp_prepare_boot_cpu(void)
	287	{
	288	BUG_ON(smp_processor_id() != boot_cpuid);
	289
	290	cpu_set(boot_cpuid, cpu_online_map);
e2075f79	291	cpu_set(boot_cpuid, per_cpu(cpu_sibling_map, boot_cpuid));
440a0857	292	cpu_set(boot_cpuid, per_cpu(cpu_core_map, boot_cpuid));
5ad57078	293	#ifdef CONFIG_PPC64
1da177e4	294	paca[boot_cpuid].__current = current;
5ad57078	295	#endif
b5e2fc1c	296	current_set[boot_cpuid] = task_thread_info(current);
1da177e4 LT	297	}
	298
	299	#ifdef CONFIG_HOTPLUG_CPU
	300	/* State of each CPU during hotplug phases */
	301	DEFINE_PER_CPU(int, cpu_state) = { 0 };
	302
	303	int generic_cpu_disable(void)
	304	{
	305	unsigned int cpu = smp_processor_id();
	306
	307	if (cpu == boot_cpuid)
	308	return -EBUSY;
	309
1da177e4	310	cpu_clear(cpu, cpu_online_map);
799d6046	311	#ifdef CONFIG_PPC64
a7f290da	312	vdso_data->processorCount--;
1da177e4	313	fixup_irqs(cpu_online_map);
094fe2e7	314	#endif
1da177e4 LT	315	return 0;
	316	}
	317
	318	int generic_cpu_enable(unsigned int cpu)
	319	{
	320	/* Do the normal bootup if we haven't
	321	* already bootstrapped. */
	322	if (system_state != SYSTEM_RUNNING)
	323	return -ENOSYS;
	324
	325	/* get the target out of it's holding state */
	326	per_cpu(cpu_state, cpu) = CPU_UP_PREPARE;
0d8d4d42	327	smp_wmb();
1da177e4 LT	328
	329	while (!cpu_online(cpu))
	330	cpu_relax();
	331
094fe2e7	332	#ifdef CONFIG_PPC64
1da177e4 LT	333	fixup_irqs(cpu_online_map);
	334	/* counter the irq disable in fixup_irqs */
	335	local_irq_enable();
094fe2e7	336	#endif
1da177e4 LT	337	return 0;
	338	}
	339
	340	void generic_cpu_die(unsigned int cpu)
	341	{
	342	int i;
	343
	344	for (i = 0; i < 100; i++) {
0d8d4d42	345	smp_rmb();
1da177e4 LT	346	if (per_cpu(cpu_state, cpu) == CPU_DEAD)
	347	return;
	348	msleep(100);
	349	}
	350	printk(KERN_ERR "CPU%d didn't die...\n", cpu);
	351	}
	352
	353	void generic_mach_cpu_die(void)
	354	{
	355	unsigned int cpu;
	356
	357	local_irq_disable();
	358	cpu = smp_processor_id();
	359	printk(KERN_DEBUG "CPU%d offline\n", cpu);
	360	__get_cpu_var(cpu_state) = CPU_DEAD;
0d8d4d42	361	smp_wmb();
1da177e4 LT	362	while (__get_cpu_var(cpu_state) != CPU_UP_PREPARE)
1da177e4 LT	363	cpu_relax();
1da177e4 LT	364	cpu_set(cpu, cpu_online_map);
	365	local_irq_enable();
	366	}
	367	#endif
	368
	369	static int __devinit cpu_enable(unsigned int cpu)
	370	{
8cffc6ac	371	if (smp_ops && smp_ops->cpu_enable)
1da177e4 LT	372	return smp_ops->cpu_enable(cpu);
	373
	374	return -ENOSYS;
	375	}
	376
b282b6f8	377	int __cpuinit __cpu_up(unsigned int cpu)
1da177e4 LT	378	{
	379	int c;
	380
5ad57078	381	secondary_ti = current_set[cpu];
1da177e4 LT	382	if (!cpu_enable(cpu))
	383	return 0;
	384
8cffc6ac BH	385	if (smp_ops == NULL \|\|
8cffc6ac BH	386	(smp_ops->cpu_bootable && !smp_ops->cpu_bootable(cpu)))
1da177e4 LT	387	return -EINVAL;
1da177e4 LT	388
1da177e4 LT	389	/* Make sure callin-map entry is 0 (can be leftover a CPU
	390	* hotplug
	391	*/
	392	cpu_callin_map[cpu] = 0;
	393
	394	/* The information for processor bringup must
	395	* be written out to main store before we release
	396	* the processor.
	397	*/
0d8d4d42	398	smp_mb();
1da177e4 LT	399
	400	/* wake up cpus */
	401	DBG("smp: kicking cpu %d\n", cpu);
	402	smp_ops->kick_cpu(cpu);
	403
	404	/*
	405	* wait to see if the cpu made a callin (is actually up).
	406	* use this value that I found through experimentation.
	407	* -- Cort
	408	*/
	409	if (system_state < SYSTEM_RUNNING)
ee0339f2	410	for (c = 50000; c && !cpu_callin_map[cpu]; c--)
1da177e4 LT	411	udelay(100);
	412	#ifdef CONFIG_HOTPLUG_CPU
	413	else
	414	/*
	415	* CPUs can take much longer to come up in the
	416	* hotplug case. Wait five seconds.
	417	*/
	418	for (c = 25; c && !cpu_callin_map[cpu]; c--) {
	419	msleep(200);
	420	}
	421	#endif
	422
	423	if (!cpu_callin_map[cpu]) {
	424	printk("Processor %u is stuck.\n", cpu);
	425	return -ENOENT;
	426	}
	427
	428	printk("Processor %u found.\n", cpu);
	429
	430	if (smp_ops->give_timebase)
	431	smp_ops->give_timebase();
	432
	433	/* Wait until cpu puts itself in the online map */
	434	while (!cpu_online(cpu))
	435	cpu_relax();
	436
	437	return 0;
	438	}
	439
e9efed3b NL	440	/* Return the value of the reg property corresponding to the given
	441	* logical cpu.
	442	*/
	443	int cpu_to_core_id(int cpu)
	444	{
	445	struct device_node *np;
	446	const int *reg;
	447	int id = -1;
	448
	449	np = of_get_cpu_node(cpu, NULL);
	450	if (!np)
	451	goto out;
	452
	453	reg = of_get_property(np, "reg", NULL);
	454	if (!reg)
	455	goto out;
	456
	457	id = *reg;
	458	out:
	459	of_node_put(np);
	460	return id;
	461	}
	462
440a0857 NL	463	/* Must be called when no change can occur to cpu_present_map,
	464	* i.e. during cpu online or offline.
	465	*/
	466	static struct device_node *cpu_to_l2cache(int cpu)
	467	{
	468	struct device_node *np;
b2ea25b9	469	struct device_node *cache;
440a0857 NL	470
	471	if (!cpu_present(cpu))
	472	return NULL;
	473
	474	np = of_get_cpu_node(cpu, NULL);
	475	if (np == NULL)
	476	return NULL;
	477
b2ea25b9 NL	478	cache = of_find_next_cache_node(np);
b2ea25b9 NL	479
440a0857 NL	480	of_node_put(np);
440a0857 NL	481
b2ea25b9	482	return cache;
440a0857	483	}
1da177e4 LT	484
	485	/* Activate a secondary processor. */
	486	int __devinit start_secondary(void *unused)
	487	{
	488	unsigned int cpu = smp_processor_id();
440a0857	489	struct device_node *l2_cache;
e2075f79	490	int i, base;
1da177e4 LT	491
	492	atomic_inc(&init_mm.mm_count);
	493	current->active_mm = &init_mm;
	494
	495	smp_store_cpu_info(cpu);
5ad57078	496	set_dec(tb_ticks_per_jiffy);
e4d76e1c	497	preempt_disable();
1da177e4 LT	498	cpu_callin_map[cpu] = 1;
	499
	500	smp_ops->setup_cpu(cpu);
	501	if (smp_ops->take_timebase)
	502	smp_ops->take_timebase();
	503
7d4d6154	504	if (system_state > SYSTEM_BOOTING)
c6622f63	505	snapshot_timebase();
7d4d6154	506
d831d0b8 TB	507	secondary_cpu_time_init();
d831d0b8 TB	508
b7d7a240	509	ipi_call_lock();
e545a614	510	notify_cpu_starting(cpu);
1da177e4	511	cpu_set(cpu, cpu_online_map);
e2075f79 NL	512	/* Update sibling maps */
	513	base = cpu_first_thread_in_core(cpu);
	514	for (i = 0; i < threads_per_core; i++) {
	515	if (cpu_is_offline(base + i))
	516	continue;
	517	cpu_set(cpu, per_cpu(cpu_sibling_map, base + i));
	518	cpu_set(base + i, per_cpu(cpu_sibling_map, cpu));
440a0857 NL	519
	520	/* cpu_core_map should be a superset of
	521	* cpu_sibling_map even if we don't have cache
	522	* information, so update the former here, too.
	523	*/
	524	cpu_set(cpu, per_cpu(cpu_core_map, base +i));
	525	cpu_set(base + i, per_cpu(cpu_core_map, cpu));
e2075f79	526	}
440a0857 NL	527	l2_cache = cpu_to_l2cache(cpu);
	528	for_each_online_cpu(i) {
	529	struct device_node *np = cpu_to_l2cache(i);
	530	if (!np)
	531	continue;
	532	if (np == l2_cache) {
	533	cpu_set(cpu, per_cpu(cpu_core_map, i));
	534	cpu_set(i, per_cpu(cpu_core_map, cpu));
	535	}
	536	of_node_put(np);
	537	}
	538	of_node_put(l2_cache);
b7d7a240	539	ipi_call_unlock();
1da177e4 LT	540
	541	local_irq_enable();
	542
	543	cpu_idle();
	544	return 0;
	545	}
	546
	547	int setup_profiling_timer(unsigned int multiplier)
	548	{
	549	return 0;
	550	}
	551
	552	void __init smp_cpus_done(unsigned int max_cpus)
	553	{
	554	cpumask_t old_mask;
	555
	556	/* We want the setup_cpu() here to be called from CPU 0, but our
	557	* init thread may have been "borrowed" by another CPU in the meantime
	558	* se we pin us down to CPU 0 for a short while
	559	*/
	560	old_mask = current->cpus_allowed;
	561	set_cpus_allowed(current, cpumask_of_cpu(boot_cpuid));
	562
8cffc6ac BH	563	if (smp_ops)
8cffc6ac BH	564	smp_ops->setup_cpu(boot_cpuid);
1da177e4 LT	565
1da177e4 LT	566	set_cpus_allowed(current, old_mask);
4b703a23	567
c6622f63 PM	568	snapshot_timebases();
c6622f63 PM	569
4b703a23	570	dump_numa_cpu_topology();
1da177e4 LT	571	}
	572
	573	#ifdef CONFIG_HOTPLUG_CPU
	574	int __cpu_disable(void)
	575	{
440a0857	576	struct device_node *l2_cache;
e2075f79 NL	577	int cpu = smp_processor_id();
	578	int base, i;
	579	int err;
1da177e4	580
e2075f79 NL	581	if (!smp_ops->cpu_disable)
	582	return -ENOSYS;
	583
	584	err = smp_ops->cpu_disable();
	585	if (err)
	586	return err;
	587
	588	/* Update sibling maps */
	589	base = cpu_first_thread_in_core(cpu);
	590	for (i = 0; i < threads_per_core; i++) {
	591	cpu_clear(cpu, per_cpu(cpu_sibling_map, base + i));
	592	cpu_clear(base + i, per_cpu(cpu_sibling_map, cpu));
440a0857 NL	593	cpu_clear(cpu, per_cpu(cpu_core_map, base +i));
	594	cpu_clear(base + i, per_cpu(cpu_core_map, cpu));
	595	}
	596
	597	l2_cache = cpu_to_l2cache(cpu);
	598	for_each_present_cpu(i) {
	599	struct device_node *np = cpu_to_l2cache(i);
	600	if (!np)
	601	continue;
	602	if (np == l2_cache) {
	603	cpu_clear(cpu, per_cpu(cpu_core_map, i));
	604	cpu_clear(i, per_cpu(cpu_core_map, cpu));
	605	}
	606	of_node_put(np);
e2075f79	607	}
440a0857 NL	608	of_node_put(l2_cache);
440a0857 NL	609
e2075f79 NL	610
e2075f79 NL	611	return 0;
1da177e4 LT	612	}
	613
	614	void __cpu_die(unsigned int cpu)
	615	{
	616	if (smp_ops->cpu_die)
	617	smp_ops->cpu_die(cpu);
	618	}
	619	#endif