[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;

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

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;

/* Can't be static due to PowerMac hackery */
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_mask(const struct cpumask *mask)
{
	unsigned int cpu;

	for_each_cpu(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)
{
	/* Remove this CPU */
	set_cpu_online(smp_processor_id(), false);

	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(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)
		if (smp_ops->probe)
			max_cpus = smp_ops->probe();
		else
			max_cpus = NR_CPUS;
	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);

	set_cpu_online(boot_cpuid, true);
	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;

	set_cpu_online(cpu, false);
#ifdef CONFIG_PPC64
	vdso_data->processorCount--;
	fixup_irqs(cpu_online_mask);
#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_mask);
	/* 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();
	set_cpu_online(cpu, true);
	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 = 5000; c && !cpu_callin_map[cpu]; c--)
			msleep(1);
#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);

#if defined(CONFIG_BOOKE) || defined(CONFIG_40x)
	/* Clear any pending timer interrupts */
	mtspr(SPRN_TSR, TSR_ENW | TSR_WIS | TSR_DIS | TSR_FIS);

	/* Enable decrementer interrupt */
	mtspr(SPRN_TCR, TCR_DIE);
#endif
	set_dec(tb_ticks_per_jiffy);
	preempt_disable();
	cpu_callin_map[cpu] = 1;

	if (smp_ops->setup_cpu)
		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);
	set_cpu_online(cpu, true);
	/* 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_var_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
	 */
	alloc_cpumask_var(&old_mask, GFP_NOWAIT);
	cpumask_copy(old_mask, &current->cpus_allowed);
	set_cpus_allowed_ptr(current, cpumask_of(boot_cpuid));
	
	if (smp_ops && smp_ops->setup_cpu)
		smp_ops->setup_cpu(boot_cpuid);

	set_cpus_allowed_ptr(current, old_mask);

	free_cpumask_var(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);
}

static DEFINE_MUTEX(powerpc_cpu_hotplug_driver_mutex);

void cpu_hotplug_driver_lock()
{
	mutex_lock(&powerpc_cpu_hotplug_driver_mutex);
}

void cpu_hotplug_driver_unlock()
{
	mutex_unlock(&powerpc_cpu_hotplug_driver_mutex);
}
#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
d5a7430d	62	DEFINE_PER_CPU(cpumask_t, cpu_sibling_map) = CPU_MASK_NONE;
440a0857	63	DEFINE_PER_CPU(cpumask_t, cpu_core_map) = CPU_MASK_NONE;
1da177e4	64
d5a7430d	65	EXPORT_PER_CPU_SYMBOL(cpu_sibling_map);
440a0857	66	EXPORT_PER_CPU_SYMBOL(cpu_core_map);
1da177e4	67
5ad57078	68	/* SMP operations for this machine */
1da177e4 LT	69	struct smp_ops_t *smp_ops;
1da177e4 LT	70
7ccbe504 BH	71	/* Can't be static due to PowerMac hackery */
7ccbe504 BH	72	volatile unsigned int cpu_callin_map[NR_CPUS];
1da177e4	73
1da177e4 LT	74	int smt_enabled_at_boot = 1;
1da177e4 LT	75
cc532915 ME	76	static void (crash_ipi_function_ptr)(struct pt_regs ) = NULL;
cc532915 ME	77
5ad57078	78	#ifdef CONFIG_PPC64
1da177e4 LT	79	void __devinit smp_generic_kick_cpu(int nr)
	80	{
	81	BUG_ON(nr < 0 \|\| nr >= NR_CPUS);
	82
	83	/*
	84	* The processor is currently spinning, waiting for the
	85	* cpu_start field to become non-zero After we set cpu_start,
	86	* the processor will continue on to secondary_start
	87	*/
	88	paca[nr].cpu_start = 1;
0d8d4d42	89	smp_mb();
1da177e4	90	}
5ad57078	91	#endif
1da177e4	92
7d12e780	93	void smp_message_recv(int msg)
1da177e4 LT	94	{
	95	switch(msg) {
	96	case PPC_MSG_CALL_FUNCTION:
b7d7a240	97	generic_smp_call_function_interrupt();
1da177e4	98	break;
5ad57078	99	case PPC_MSG_RESCHEDULE:
22d660ff	100	/* we notice need_resched on exit */
1da177e4	101	break;
b7d7a240 JA	102	case PPC_MSG_CALL_FUNC_SINGLE:
	103	generic_smp_call_function_single_interrupt();
	104	break;
1da177e4	105	case PPC_MSG_DEBUGGER_BREAK:
cc532915	106	if (crash_ipi_function_ptr) {
7d12e780	107	crash_ipi_function_ptr(get_irq_regs());
cc532915 ME	108	break;
	109	}
	110	#ifdef CONFIG_DEBUGGER
7d12e780	111	debugger_ipi(get_irq_regs());
1da177e4	112	break;
cc532915 ME	113	#endif /* CONFIG_DEBUGGER */
cc532915 ME	114	/* FALLTHROUGH */
1da177e4 LT	115	default:
	116	printk("SMP %d: smp_message_recv(): unknown msg %d\n",
	117	smp_processor_id(), msg);
	118	break;
	119	}
	120	}
	121
25ddd738 MM	122	static irqreturn_t call_function_action(int irq, void *data)
	123	{
	124	generic_smp_call_function_interrupt();
	125	return IRQ_HANDLED;
	126	}
	127
	128	static irqreturn_t reschedule_action(int irq, void *data)
	129	{
	130	/* we just need the return path side effect of checking need_resched */
	131	return IRQ_HANDLED;
	132	}
	133
	134	static irqreturn_t call_function_single_action(int irq, void *data)
	135	{
	136	generic_smp_call_function_single_interrupt();
	137	return IRQ_HANDLED;
	138	}
	139
	140	static irqreturn_t debug_ipi_action(int irq, void *data)
	141	{
	142	smp_message_recv(PPC_MSG_DEBUGGER_BREAK);
	143	return IRQ_HANDLED;
	144	}
	145
	146	static irq_handler_t smp_ipi_action[] = {
	147	[PPC_MSG_CALL_FUNCTION] = call_function_action,
	148	[PPC_MSG_RESCHEDULE] = reschedule_action,
	149	[PPC_MSG_CALL_FUNC_SINGLE] = call_function_single_action,
	150	[PPC_MSG_DEBUGGER_BREAK] = debug_ipi_action,
	151	};
	152
	153	const char *smp_ipi_name[] = {
	154	[PPC_MSG_CALL_FUNCTION] = "ipi call function",
	155	[PPC_MSG_RESCHEDULE] = "ipi reschedule",
	156	[PPC_MSG_CALL_FUNC_SINGLE] = "ipi call function single",
	157	[PPC_MSG_DEBUGGER_BREAK] = "ipi debugger",
	158	};
	159
	160	/* optional function to request ipi, for controllers with >= 4 ipis */
	161	int smp_request_message_ipi(int virq, int msg)
	162	{
	163	int err;
	164
	165	if (msg < 0 \|\| msg > PPC_MSG_DEBUGGER_BREAK) {
	166	return -EINVAL;
	167	}
	168	#if !defined(CONFIG_DEBUGGER) && !defined(CONFIG_KEXEC)
	169	if (msg == PPC_MSG_DEBUGGER_BREAK) {
	170	return 1;
	171	}
	172	#endif
	173	err = request_irq(virq, smp_ipi_action[msg], IRQF_DISABLED\|IRQF_PERCPU,
	174	smp_ipi_name[msg], 0);
	175	WARN(err < 0, "unable to request_irq %d for %s (rc %d)\n",
	176	virq, smp_ipi_name[msg], err);
	177
	178	return err;
	179	}
	180
1da177e4 LT	181	void smp_send_reschedule(int cpu)
1da177e4 LT	182	{
8cffc6ac BH	183	if (likely(smp_ops))
8cffc6ac BH	184	smp_ops->message_pass(cpu, PPC_MSG_RESCHEDULE);
1da177e4 LT	185	}
1da177e4 LT	186
b7d7a240 JA	187	void arch_send_call_function_single_ipi(int cpu)
	188	{
	189	smp_ops->message_pass(cpu, PPC_MSG_CALL_FUNC_SINGLE);
	190	}
	191
f063ea02	192	void arch_send_call_function_ipi_mask(const struct cpumask *mask)
b7d7a240 JA	193	{
	194	unsigned int cpu;
	195
f063ea02	196	for_each_cpu(cpu, mask)
b7d7a240 JA	197	smp_ops->message_pass(cpu, PPC_MSG_CALL_FUNCTION);
	198	}
	199
1da177e4 LT	200	#ifdef CONFIG_DEBUGGER
	201	void smp_send_debugger_break(int cpu)
	202	{
8cffc6ac BH	203	if (likely(smp_ops))
8cffc6ac BH	204	smp_ops->message_pass(cpu, PPC_MSG_DEBUGGER_BREAK);
1da177e4 LT	205	}
	206	#endif
	207
cc532915 ME	208	#ifdef CONFIG_KEXEC
	209	void crash_send_ipi(void (crash_ipi_callback)(struct pt_regs ))
	210	{
	211	crash_ipi_function_ptr = crash_ipi_callback;
8cffc6ac	212	if (crash_ipi_callback && smp_ops) {
cc532915 ME	213	mb();
	214	smp_ops->message_pass(MSG_ALL_BUT_SELF, PPC_MSG_DEBUGGER_BREAK);
	215	}
	216	}
	217	#endif
	218
1da177e4 LT	219	static void stop_this_cpu(void *dummy)
1da177e4 LT	220	{
8389b37d VB	221	/* Remove this CPU */
	222	set_cpu_online(smp_processor_id(), false);
	223
1da177e4 LT	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)
1da177e4 LT	237	{
6b7487fc	238	per_cpu(cpu_pvr, id) = mfspr(SPRN_PVR);
1da177e4 LT	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	274	if (smp_ops)
757cbd46 KG	275	if (smp_ops->probe)
	276	max_cpus = smp_ops->probe();
	277	else
	278	max_cpus = NR_CPUS;
8cffc6ac BH	279	else
8cffc6ac BH	280	max_cpus = 1;
1da177e4 LT	281
	282	smp_space_timers(max_cpus);
	283
0e551954	284	for_each_possible_cpu(cpu)
1da177e4 LT	285	if (cpu != boot_cpuid)
	286	smp_create_idle(cpu);
	287	}
	288
	289	void __devinit smp_prepare_boot_cpu(void)
	290	{
	291	BUG_ON(smp_processor_id() != boot_cpuid);
	292
ea0f1cab	293	set_cpu_online(boot_cpuid, true);
e2075f79	294	cpu_set(boot_cpuid, per_cpu(cpu_sibling_map, boot_cpuid));
440a0857	295	cpu_set(boot_cpuid, per_cpu(cpu_core_map, boot_cpuid));
5ad57078	296	#ifdef CONFIG_PPC64
1da177e4	297	paca[boot_cpuid].__current = current;
5ad57078	298	#endif
b5e2fc1c	299	current_set[boot_cpuid] = task_thread_info(current);
1da177e4 LT	300	}
	301
	302	#ifdef CONFIG_HOTPLUG_CPU
	303	/* State of each CPU during hotplug phases */
	304	DEFINE_PER_CPU(int, cpu_state) = { 0 };
	305
	306	int generic_cpu_disable(void)
	307	{
	308	unsigned int cpu = smp_processor_id();
	309
	310	if (cpu == boot_cpuid)
	311	return -EBUSY;
	312
ea0f1cab	313	set_cpu_online(cpu, false);
799d6046	314	#ifdef CONFIG_PPC64
a7f290da	315	vdso_data->processorCount--;
b6decb70	316	fixup_irqs(cpu_online_mask);
094fe2e7	317	#endif
1da177e4 LT	318	return 0;
	319	}
	320
	321	int generic_cpu_enable(unsigned int cpu)
	322	{
	323	/* Do the normal bootup if we haven't
	324	* already bootstrapped. */
	325	if (system_state != SYSTEM_RUNNING)
	326	return -ENOSYS;
	327
	328	/* get the target out of it's holding state */
	329	per_cpu(cpu_state, cpu) = CPU_UP_PREPARE;
0d8d4d42	330	smp_wmb();
1da177e4 LT	331
	332	while (!cpu_online(cpu))
	333	cpu_relax();
	334
094fe2e7	335	#ifdef CONFIG_PPC64
b6decb70	336	fixup_irqs(cpu_online_mask);
1da177e4 LT	337	/* counter the irq disable in fixup_irqs */
1da177e4 LT	338	local_irq_enable();
094fe2e7	339	#endif
1da177e4 LT	340	return 0;
	341	}
	342
	343	void generic_cpu_die(unsigned int cpu)
	344	{
	345	int i;
	346
	347	for (i = 0; i < 100; i++) {
0d8d4d42	348	smp_rmb();
1da177e4 LT	349	if (per_cpu(cpu_state, cpu) == CPU_DEAD)
	350	return;
	351	msleep(100);
	352	}
	353	printk(KERN_ERR "CPU%d didn't die...\n", cpu);
	354	}
	355
	356	void generic_mach_cpu_die(void)
	357	{
	358	unsigned int cpu;
	359
	360	local_irq_disable();
	361	cpu = smp_processor_id();
	362	printk(KERN_DEBUG "CPU%d offline\n", cpu);
	363	__get_cpu_var(cpu_state) = CPU_DEAD;
0d8d4d42	364	smp_wmb();
1da177e4 LT	365	while (__get_cpu_var(cpu_state) != CPU_UP_PREPARE)
1da177e4 LT	366	cpu_relax();
ea0f1cab	367	set_cpu_online(cpu, true);
1da177e4 LT	368	local_irq_enable();
	369	}
	370	#endif
	371
	372	static int __devinit cpu_enable(unsigned int cpu)
	373	{
8cffc6ac	374	if (smp_ops && smp_ops->cpu_enable)
1da177e4 LT	375	return smp_ops->cpu_enable(cpu);
	376
	377	return -ENOSYS;
	378	}
	379
b282b6f8	380	int __cpuinit __cpu_up(unsigned int cpu)
1da177e4 LT	381	{
	382	int c;
	383
5ad57078	384	secondary_ti = current_set[cpu];
1da177e4 LT	385	if (!cpu_enable(cpu))
	386	return 0;
	387
8cffc6ac BH	388	if (smp_ops == NULL \|\|
8cffc6ac BH	389	(smp_ops->cpu_bootable && !smp_ops->cpu_bootable(cpu)))
1da177e4 LT	390	return -EINVAL;
1da177e4 LT	391
1da177e4 LT	392	/* Make sure callin-map entry is 0 (can be leftover a CPU
	393	* hotplug
	394	*/
	395	cpu_callin_map[cpu] = 0;
	396
	397	/* The information for processor bringup must
	398	* be written out to main store before we release
	399	* the processor.
	400	*/
0d8d4d42	401	smp_mb();
1da177e4 LT	402
	403	/* wake up cpus */
	404	DBG("smp: kicking cpu %d\n", cpu);
	405	smp_ops->kick_cpu(cpu);
	406
	407	/*
	408	* wait to see if the cpu made a callin (is actually up).
	409	* use this value that I found through experimentation.
	410	* -- Cort
	411	*/
	412	if (system_state < SYSTEM_RUNNING)
ee0339f2	413	for (c = 50000; c && !cpu_callin_map[cpu]; c--)
1da177e4 LT	414	udelay(100);
	415	#ifdef CONFIG_HOTPLUG_CPU
	416	else
	417	/*
	418	* CPUs can take much longer to come up in the
	419	* hotplug case. Wait five seconds.
	420	*/
67764263 GS	421	for (c = 5000; c && !cpu_callin_map[cpu]; c--)
67764263 GS	422	msleep(1);
1da177e4 LT	423	#endif
	424
	425	if (!cpu_callin_map[cpu]) {
	426	printk("Processor %u is stuck.\n", cpu);
	427	return -ENOENT;
	428	}
	429
	430	printk("Processor %u found.\n", cpu);
	431
	432	if (smp_ops->give_timebase)
	433	smp_ops->give_timebase();
	434
	435	/* Wait until cpu puts itself in the online map */
	436	while (!cpu_online(cpu))
	437	cpu_relax();
	438
	439	return 0;
	440	}
	441
e9efed3b NL	442	/* Return the value of the reg property corresponding to the given
	443	* logical cpu.
	444	*/
	445	int cpu_to_core_id(int cpu)
	446	{
	447	struct device_node *np;
	448	const int *reg;
	449	int id = -1;
	450
	451	np = of_get_cpu_node(cpu, NULL);
	452	if (!np)
	453	goto out;
	454
	455	reg = of_get_property(np, "reg", NULL);
	456	if (!reg)
	457	goto out;
	458
	459	id = *reg;
	460	out:
	461	of_node_put(np);
	462	return id;
	463	}
	464
440a0857 NL	465	/* Must be called when no change can occur to cpu_present_map,
	466	* i.e. during cpu online or offline.
	467	*/
	468	static struct device_node *cpu_to_l2cache(int cpu)
	469	{
	470	struct device_node *np;
b2ea25b9	471	struct device_node *cache;
440a0857 NL	472
	473	if (!cpu_present(cpu))
	474	return NULL;
	475
	476	np = of_get_cpu_node(cpu, NULL);
	477	if (np == NULL)
	478	return NULL;
	479
b2ea25b9 NL	480	cache = of_find_next_cache_node(np);
b2ea25b9 NL	481
440a0857 NL	482	of_node_put(np);
440a0857 NL	483
b2ea25b9	484	return cache;
440a0857	485	}
1da177e4 LT	486
	487	/* Activate a secondary processor. */
	488	int __devinit start_secondary(void *unused)
	489	{
	490	unsigned int cpu = smp_processor_id();
440a0857	491	struct device_node *l2_cache;
e2075f79	492	int i, base;
1da177e4 LT	493
	494	atomic_inc(&init_mm.mm_count);
	495	current->active_mm = &init_mm;
	496
	497	smp_store_cpu_info(cpu);
e7f75ad0 DK	498
	499	#if defined(CONFIG_BOOKE) \|\| defined(CONFIG_40x)
	500	/* Clear any pending timer interrupts */
	501	mtspr(SPRN_TSR, TSR_ENW \| TSR_WIS \| TSR_DIS \| TSR_FIS);
	502
	503	/* Enable decrementer interrupt */
	504	mtspr(SPRN_TCR, TCR_DIE);
	505	#endif
5ad57078	506	set_dec(tb_ticks_per_jiffy);
e4d76e1c	507	preempt_disable();
1da177e4 LT	508	cpu_callin_map[cpu] = 1;
1da177e4 LT	509
757cbd46 KG	510	if (smp_ops->setup_cpu)
757cbd46 KG	511	smp_ops->setup_cpu(cpu);
1da177e4 LT	512	if (smp_ops->take_timebase)
	513	smp_ops->take_timebase();
	514
7d4d6154	515	if (system_state > SYSTEM_BOOTING)
c6622f63	516	snapshot_timebase();
7d4d6154	517
d831d0b8 TB	518	secondary_cpu_time_init();
d831d0b8 TB	519
b7d7a240	520	ipi_call_lock();
e545a614	521	notify_cpu_starting(cpu);
ea0f1cab	522	set_cpu_online(cpu, true);
e2075f79 NL	523	/* Update sibling maps */
	524	base = cpu_first_thread_in_core(cpu);
	525	for (i = 0; i < threads_per_core; i++) {
	526	if (cpu_is_offline(base + i))
	527	continue;
	528	cpu_set(cpu, per_cpu(cpu_sibling_map, base + i));
	529	cpu_set(base + i, per_cpu(cpu_sibling_map, cpu));
440a0857 NL	530
	531	/* cpu_core_map should be a superset of
	532	* cpu_sibling_map even if we don't have cache
	533	* information, so update the former here, too.
	534	*/
	535	cpu_set(cpu, per_cpu(cpu_core_map, base +i));
	536	cpu_set(base + i, per_cpu(cpu_core_map, cpu));
e2075f79	537	}
440a0857 NL	538	l2_cache = cpu_to_l2cache(cpu);
	539	for_each_online_cpu(i) {
	540	struct device_node *np = cpu_to_l2cache(i);
	541	if (!np)
	542	continue;
	543	if (np == l2_cache) {
	544	cpu_set(cpu, per_cpu(cpu_core_map, i));
	545	cpu_set(i, per_cpu(cpu_core_map, cpu));
	546	}
	547	of_node_put(np);
	548	}
	549	of_node_put(l2_cache);
b7d7a240	550	ipi_call_unlock();
1da177e4 LT	551
	552	local_irq_enable();
	553
	554	cpu_idle();
	555	return 0;
	556	}
	557
	558	int setup_profiling_timer(unsigned int multiplier)
	559	{
	560	return 0;
	561	}
	562
	563	void __init smp_cpus_done(unsigned int max_cpus)
	564	{
bfb9126d	565	cpumask_var_t old_mask;
1da177e4 LT	566
	567	/* We want the setup_cpu() here to be called from CPU 0, but our
	568	* init thread may have been "borrowed" by another CPU in the meantime
	569	* se we pin us down to CPU 0 for a short while
	570	*/
bfb9126d AB	571	alloc_cpumask_var(&old_mask, GFP_NOWAIT);
bfb9126d AB	572	cpumask_copy(old_mask, &current->cpus_allowed);
21dbeb91	573	set_cpus_allowed_ptr(current, cpumask_of(boot_cpuid));
1da177e4	574
757cbd46	575	if (smp_ops && smp_ops->setup_cpu)
8cffc6ac	576	smp_ops->setup_cpu(boot_cpuid);
1da177e4	577
bfb9126d AB	578	set_cpus_allowed_ptr(current, old_mask);
	579
	580	free_cpumask_var(old_mask);
4b703a23	581
c6622f63 PM	582	snapshot_timebases();
c6622f63 PM	583
4b703a23	584	dump_numa_cpu_topology();
1da177e4 LT	585	}
	586
	587	#ifdef CONFIG_HOTPLUG_CPU
	588	int __cpu_disable(void)
	589	{
440a0857	590	struct device_node *l2_cache;
e2075f79 NL	591	int cpu = smp_processor_id();
	592	int base, i;
	593	int err;
1da177e4	594
e2075f79 NL	595	if (!smp_ops->cpu_disable)
	596	return -ENOSYS;
	597
	598	err = smp_ops->cpu_disable();
	599	if (err)
	600	return err;
	601
	602	/* Update sibling maps */
	603	base = cpu_first_thread_in_core(cpu);
	604	for (i = 0; i < threads_per_core; i++) {
	605	cpu_clear(cpu, per_cpu(cpu_sibling_map, base + i));
	606	cpu_clear(base + i, per_cpu(cpu_sibling_map, cpu));
440a0857 NL	607	cpu_clear(cpu, per_cpu(cpu_core_map, base +i));
	608	cpu_clear(base + i, per_cpu(cpu_core_map, cpu));
	609	}
	610
	611	l2_cache = cpu_to_l2cache(cpu);
	612	for_each_present_cpu(i) {
	613	struct device_node *np = cpu_to_l2cache(i);
	614	if (!np)
	615	continue;
	616	if (np == l2_cache) {
	617	cpu_clear(cpu, per_cpu(cpu_core_map, i));
	618	cpu_clear(i, per_cpu(cpu_core_map, cpu));
	619	}
	620	of_node_put(np);
e2075f79	621	}
440a0857 NL	622	of_node_put(l2_cache);
440a0857 NL	623
e2075f79 NL	624
e2075f79 NL	625	return 0;
1da177e4 LT	626	}
	627
	628	void __cpu_die(unsigned int cpu)
	629	{
	630	if (smp_ops->cpu_die)
	631	smp_ops->cpu_die(cpu);
	632	}
d0174c72 NF	633
	634	static DEFINE_MUTEX(powerpc_cpu_hotplug_driver_mutex);
	635
	636	void cpu_hotplug_driver_lock()
	637	{
	638	mutex_lock(&powerpc_cpu_hotplug_driver_mutex);
	639	}
	640
	641	void cpu_hotplug_driver_unlock()
	642	{
	643	mutex_unlock(&powerpc_cpu_hotplug_driver_mutex);
	644	}
1da177e4	645	#endif