kernel-ark/arch/ppc64/kernel/smp.c
Arnd Bergmann cebf589c82 [PATCH] ppc64: Add driver for BPA interrupt controllers
Add support for the integrated interrupt controller on BPA
CPUs. There is one of those for each SMT thread.

The mapping of interrupt numbers to HW interrupt sources
is described in arch/ppc64/kernel/bpa_iic.h.

This version hardcodes the 'Spider' chip as the secondary
interrupt controller. That is not really generic for the
architecture, but at the moment it is the only secondary
PIC that exists.

A little more work will be needed on this as soon as
we have boards with multiple external interrupt controllers.

Signed-off-by: Arnd Bergmann <arndb@de.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2005-06-23 09:43:43 +10:00

622 lines
13 KiB
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/config.h>
#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 <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/paca.h>
#include <asm/time.h>
#include <asm/machdep.h>
#include <asm/cputable.h>
#include <asm/system.h>
#include <asm/abs_addr.h>
#include "mpic.h"
#ifdef DEBUG
#define DBG(fmt...) udbg_printf(fmt)
#else
#define DBG(fmt...)
#endif
cpumask_t cpu_possible_map = CPU_MASK_NONE;
cpumask_t cpu_online_map = CPU_MASK_NONE;
cpumask_t cpu_sibling_map[NR_CPUS] = { [0 ... NR_CPUS-1] = CPU_MASK_NONE };
EXPORT_SYMBOL(cpu_online_map);
EXPORT_SYMBOL(cpu_possible_map);
struct smp_ops_t *smp_ops;
static volatile unsigned int cpu_callin_map[NR_CPUS];
extern unsigned char stab_array[];
void smp_call_function_interrupt(void);
int smt_enabled_at_boot = 1;
#ifdef CONFIG_MPIC
void smp_mpic_message_pass(int target, int msg)
{
/* make sure we're sending something that translates to an IPI */
if ( msg > 0x3 ){
printk("SMP %d: smp_message_pass: unknown msg %d\n",
smp_processor_id(), msg);
return;
}
switch ( target )
{
case MSG_ALL:
mpic_send_ipi(msg, 0xffffffff);
break;
case MSG_ALL_BUT_SELF:
mpic_send_ipi(msg, 0xffffffff & ~(1 << smp_processor_id()));
break;
default:
mpic_send_ipi(msg, 1 << target);
break;
}
}
int __init smp_mpic_probe(void)
{
int nr_cpus;
DBG("smp_mpic_probe()...\n");
nr_cpus = cpus_weight(cpu_possible_map);
DBG("nr_cpus: %d\n", nr_cpus);
if (nr_cpus > 1)
mpic_request_ipis();
return nr_cpus;
}
void __devinit smp_mpic_setup_cpu(int cpu)
{
mpic_setup_this_cpu();
}
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 /* CONFIG_MPIC */
static void __init smp_space_timers(unsigned int max_cpus)
{
int i;
unsigned long offset = tb_ticks_per_jiffy / max_cpus;
unsigned long previous_tb = paca[boot_cpuid].next_jiffy_update_tb;
for_each_cpu(i) {
if (i != boot_cpuid) {
paca[i].next_jiffy_update_tb =
previous_tb + offset;
previous_tb = paca[i].next_jiffy_update_tb;
}
}
}
void smp_message_recv(int msg, struct pt_regs *regs)
{
switch(msg) {
case PPC_MSG_CALL_FUNCTION:
smp_call_function_interrupt();
break;
case PPC_MSG_RESCHEDULE:
/* XXX Do we have to do this? */
set_need_resched();
break;
#if 0
case PPC_MSG_MIGRATE_TASK:
/* spare */
break;
#endif
#ifdef CONFIG_DEBUGGER
case PPC_MSG_DEBUGGER_BREAK:
debugger_ipi(regs);
break;
#endif
default:
printk("SMP %d: smp_message_recv(): unknown msg %d\n",
smp_processor_id(), msg);
break;
}
}
void smp_send_reschedule(int cpu)
{
smp_ops->message_pass(cpu, PPC_MSG_RESCHEDULE);
}
#ifdef CONFIG_DEBUGGER
void smp_send_debugger_break(int cpu)
{
smp_ops->message_pass(cpu, 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, 1, 0);
}
/*
* Structure and data for smp_call_function(). This is designed to minimise
* static memory requirements. It also looks cleaner.
* Stolen from the i386 version.
*/
static __cacheline_aligned_in_smp DEFINE_SPINLOCK(call_lock);
static struct call_data_struct {
void (*func) (void *info);
void *info;
atomic_t started;
atomic_t finished;
int wait;
} *call_data;
/* delay of at least 8 seconds on 1GHz cpu */
#define SMP_CALL_TIMEOUT (1UL << (30 + 3))
/*
* This function sends a 'generic call function' IPI to all other CPUs
* in the system.
*
* [SUMMARY] Run a function on all other CPUs.
* <func> The function to run. This must be fast and non-blocking.
* <info> An arbitrary pointer to pass to the function.
* <nonatomic> currently unused.
* <wait> If true, wait (atomically) until function has completed on other CPUs.
* [RETURNS] 0 on success, else a negative status code. Does not return until
* remote CPUs are nearly ready to execute <<func>> or are or have executed.
*
* You must not call this function with disabled interrupts or from a
* hardware interrupt handler or from a bottom half handler.
*/
int smp_call_function (void (*func) (void *info), void *info, int nonatomic,
int wait)
{
struct call_data_struct data;
int ret = -1, cpus;
unsigned long timeout;
/* Can deadlock when called with interrupts disabled */
WARN_ON(irqs_disabled());
data.func = func;
data.info = info;
atomic_set(&data.started, 0);
data.wait = wait;
if (wait)
atomic_set(&data.finished, 0);
spin_lock(&call_lock);
/* Must grab online cpu count with preempt disabled, otherwise
* it can change. */
cpus = num_online_cpus() - 1;
if (!cpus) {
ret = 0;
goto out;
}
call_data = &data;
smp_wmb();
/* Send a message to all other CPUs and wait for them to respond */
smp_ops->message_pass(MSG_ALL_BUT_SELF, PPC_MSG_CALL_FUNCTION);
/* Wait for response */
timeout = SMP_CALL_TIMEOUT;
while (atomic_read(&data.started) != cpus) {
HMT_low();
if (--timeout == 0) {
printk("smp_call_function on cpu %d: other cpus not "
"responding (%d)\n", smp_processor_id(),
atomic_read(&data.started));
debugger(NULL);
goto out;
}
}
if (wait) {
timeout = SMP_CALL_TIMEOUT;
while (atomic_read(&data.finished) != cpus) {
HMT_low();
if (--timeout == 0) {
printk("smp_call_function on cpu %d: other "
"cpus not finishing (%d/%d)\n",
smp_processor_id(),
atomic_read(&data.finished),
atomic_read(&data.started));
debugger(NULL);
goto out;
}
}
}
ret = 0;
out:
call_data = NULL;
HMT_medium();
spin_unlock(&call_lock);
return ret;
}
EXPORT_SYMBOL(smp_call_function);
void smp_call_function_interrupt(void)
{
void (*func) (void *info);
void *info;
int wait;
/* call_data will be NULL if the sender timed out while
* waiting on us to receive the call.
*/
if (!call_data)
return;
func = call_data->func;
info = call_data->info;
wait = call_data->wait;
if (!wait)
smp_mb__before_atomic_inc();
/*
* Notify initiating CPU that I've grabbed the data and am
* about to execute the function
*/
atomic_inc(&call_data->started);
/*
* At this point the info structure may be out of scope unless wait==1
*/
(*func)(info);
if (wait) {
smp_mb__before_atomic_inc();
atomic_inc(&call_data->finished);
}
}
extern struct gettimeofday_struct do_gtod;
struct thread_info *current_set[NR_CPUS];
DECLARE_PER_CPU(unsigned int, pvr);
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));
paca[cpu].__current = p;
current_set[cpu] = p->thread_info;
}
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;
#ifndef CONFIG_PPC_ISERIES
paca[boot_cpuid].next_jiffy_update_tb = tb_last_stamp = get_tb();
/*
* Should update do_gtod.stamp_xsec.
* For now we leave it which means the time can be some
* number of msecs off until someone does a settimeofday()
*/
do_gtod.varp->tb_orig_stamp = tb_last_stamp;
systemcfg->tb_orig_stamp = tb_last_stamp;
#endif
max_cpus = smp_ops->probe();
smp_space_timers(max_cpus);
for_each_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);
paca[boot_cpuid].__current = current;
current_set[boot_cpuid] = current->thread_info;
}
#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;
systemcfg->processorCount--;
cpu_clear(cpu, cpu_online_map);
fixup_irqs(cpu_online_map);
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();
fixup_irqs(cpu_online_map);
/* counter the irq disable in fixup_irqs */
local_irq_enable();
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();
flush_tlb_pending();
cpu_set(cpu, cpu_online_map);
local_irq_enable();
}
#endif
static int __devinit cpu_enable(unsigned int cpu)
{
if (smp_ops->cpu_enable)
return smp_ops->cpu_enable(cpu);
return -ENOSYS;
}
int __devinit __cpu_up(unsigned int cpu)
{
int c;
if (!cpu_enable(cpu))
return 0;
if (smp_ops->cpu_bootable && !smp_ops->cpu_bootable(cpu))
return -EINVAL;
paca[cpu].default_decr = tb_ticks_per_jiffy;
if (!cpu_has_feature(CPU_FTR_SLB)) {
void *tmp;
/* maximum of 48 CPUs on machines with a segment table */
if (cpu >= 48)
BUG();
tmp = &stab_array[PAGE_SIZE * cpu];
memset(tmp, 0, PAGE_SIZE);
paca[cpu].stab_addr = (unsigned long)tmp;
paca[cpu].stab_real = virt_to_abs(tmp);
}
/* 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 = 5000; 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;
}
/* Activate a secondary processor. */
int __devinit start_secondary(void *unused)
{
unsigned int cpu = smp_processor_id();
atomic_inc(&init_mm.mm_count);
current->active_mm = &init_mm;
smp_store_cpu_info(cpu);
set_dec(paca[cpu].default_decr);
cpu_callin_map[cpu] = 1;
smp_ops->setup_cpu(cpu);
if (smp_ops->take_timebase)
smp_ops->take_timebase();
spin_lock(&call_lock);
cpu_set(cpu, cpu_online_map);
spin_unlock(&call_lock);
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));
smp_ops->setup_cpu(boot_cpuid);
set_cpus_allowed(current, old_mask);
}
#ifdef CONFIG_HOTPLUG_CPU
int __cpu_disable(void)
{
if (smp_ops->cpu_disable)
return smp_ops->cpu_disable();
return -ENOSYS;
}
void __cpu_die(unsigned int cpu)
{
if (smp_ops->cpu_die)
smp_ops->cpu_die(cpu);
}
#endif