linux/arch/sparc/kernel/sun4d_smp.c
David S. Miller c68e5d39a5 sparc32: Implement hard_smp_processor_id() via instruction patching.
This is the last non-trivial user of btfixup.

Like sparc64, use a special patch section to resolve the various
implementations of how to read the current CPU's ID when we don't
have current_thread_info()->cpu necessarily available.

Signed-off-by: David S. Miller <davem@davemloft.net>
Tested-by: Sam Ravnborg <sam@ravnborg.org>
2012-05-14 13:31:38 -07:00

412 lines
9.4 KiB
C

/* Sparc SS1000/SC2000 SMP support.
*
* Copyright (C) 1998 Jakub Jelinek (jj@sunsite.mff.cuni.cz)
*
* Based on sun4m's smp.c, which is:
* Copyright (C) 1996 David S. Miller (davem@caip.rutgers.edu)
*/
#include <linux/clockchips.h>
#include <linux/interrupt.h>
#include <linux/profile.h>
#include <linux/delay.h>
#include <linux/sched.h>
#include <linux/cpu.h>
#include <asm/cacheflush.h>
#include <asm/switch_to.h>
#include <asm/tlbflush.h>
#include <asm/timer.h>
#include <asm/oplib.h>
#include <asm/sbi.h>
#include <asm/mmu.h>
#include "kernel.h"
#include "irq.h"
#define IRQ_CROSS_CALL 15
static volatile int smp_processors_ready;
static int smp_highest_cpu;
static inline unsigned long sun4d_swap(volatile unsigned long *ptr, unsigned long val)
{
__asm__ __volatile__("swap [%1], %0\n\t" :
"=&r" (val), "=&r" (ptr) :
"0" (val), "1" (ptr));
return val;
}
static void smp4d_ipi_init(void);
static unsigned char cpu_leds[32];
static inline void show_leds(int cpuid)
{
cpuid &= 0x1e;
__asm__ __volatile__ ("stba %0, [%1] %2" : :
"r" ((cpu_leds[cpuid] << 4) | cpu_leds[cpuid+1]),
"r" (ECSR_BASE(cpuid) | BB_LEDS),
"i" (ASI_M_CTL));
}
void __cpuinit smp4d_callin(void)
{
int cpuid = hard_smp_processor_id();
unsigned long flags;
/* Show we are alive */
cpu_leds[cpuid] = 0x6;
show_leds(cpuid);
/* Enable level15 interrupt, disable level14 interrupt for now */
cc_set_imsk((cc_get_imsk() & ~0x8000) | 0x4000);
local_ops->cache_all();
local_ops->tlb_all();
notify_cpu_starting(cpuid);
/*
* Unblock the master CPU _only_ when the scheduler state
* of all secondary CPUs will be up-to-date, so after
* the SMP initialization the master will be just allowed
* to call the scheduler code.
*/
/* Get our local ticker going. */
register_percpu_ce(cpuid);
calibrate_delay();
smp_store_cpu_info(cpuid);
local_ops->cache_all();
local_ops->tlb_all();
/* Allow master to continue. */
sun4d_swap((unsigned long *)&cpu_callin_map[cpuid], 1);
local_ops->cache_all();
local_ops->tlb_all();
while ((unsigned long)current_set[cpuid] < PAGE_OFFSET)
barrier();
while (current_set[cpuid]->cpu != cpuid)
barrier();
/* Fix idle thread fields. */
__asm__ __volatile__("ld [%0], %%g6\n\t"
: : "r" (&current_set[cpuid])
: "memory" /* paranoid */);
cpu_leds[cpuid] = 0x9;
show_leds(cpuid);
/* Attach to the address space of init_task. */
atomic_inc(&init_mm.mm_count);
current->active_mm = &init_mm;
local_ops->cache_all();
local_ops->tlb_all();
local_irq_enable(); /* We don't allow PIL 14 yet */
while (!cpumask_test_cpu(cpuid, &smp_commenced_mask))
barrier();
spin_lock_irqsave(&sun4d_imsk_lock, flags);
cc_set_imsk(cc_get_imsk() & ~0x4000); /* Allow PIL 14 as well */
spin_unlock_irqrestore(&sun4d_imsk_lock, flags);
set_cpu_online(cpuid, true);
}
/*
* Cycle through the processors asking the PROM to start each one.
*/
void __init smp4d_boot_cpus(void)
{
smp4d_ipi_init();
if (boot_cpu_id)
current_set[0] = NULL;
local_ops->cache_all();
}
int __cpuinit smp4d_boot_one_cpu(int i)
{
unsigned long *entry = &sun4d_cpu_startup;
struct task_struct *p;
int timeout;
int cpu_node;
cpu_find_by_instance(i, &cpu_node, NULL);
/* Cook up an idler for this guy. */
p = fork_idle(i);
current_set[i] = task_thread_info(p);
/*
* Initialize the contexts table
* Since the call to prom_startcpu() trashes the structure,
* we need to re-initialize it for each cpu
*/
smp_penguin_ctable.which_io = 0;
smp_penguin_ctable.phys_addr = (unsigned int) srmmu_ctx_table_phys;
smp_penguin_ctable.reg_size = 0;
/* whirrr, whirrr, whirrrrrrrrr... */
printk(KERN_INFO "Starting CPU %d at %p\n", i, entry);
local_ops->cache_all();
prom_startcpu(cpu_node,
&smp_penguin_ctable, 0, (char *)entry);
printk(KERN_INFO "prom_startcpu returned :)\n");
/* wheee... it's going... */
for (timeout = 0; timeout < 10000; timeout++) {
if (cpu_callin_map[i])
break;
udelay(200);
}
if (!(cpu_callin_map[i])) {
printk(KERN_ERR "Processor %d is stuck.\n", i);
return -ENODEV;
}
local_ops->cache_all();
return 0;
}
void __init smp4d_smp_done(void)
{
int i, first;
int *prev;
/* setup cpu list for irq rotation */
first = 0;
prev = &first;
for_each_online_cpu(i) {
*prev = i;
prev = &cpu_data(i).next;
}
*prev = first;
local_ops->cache_all();
/* Ok, they are spinning and ready to go. */
smp_processors_ready = 1;
sun4d_distribute_irqs();
}
/* Memory structure giving interrupt handler information about IPI generated */
struct sun4d_ipi_work {
int single;
int msk;
int resched;
};
static DEFINE_PER_CPU_SHARED_ALIGNED(struct sun4d_ipi_work, sun4d_ipi_work);
/* Initialize IPIs on the SUN4D SMP machine */
static void __init smp4d_ipi_init(void)
{
int cpu;
struct sun4d_ipi_work *work;
printk(KERN_INFO "smp4d: setup IPI at IRQ %d\n", SUN4D_IPI_IRQ);
for_each_possible_cpu(cpu) {
work = &per_cpu(sun4d_ipi_work, cpu);
work->single = work->msk = work->resched = 0;
}
}
void sun4d_ipi_interrupt(void)
{
struct sun4d_ipi_work *work = &__get_cpu_var(sun4d_ipi_work);
if (work->single) {
work->single = 0;
smp_call_function_single_interrupt();
}
if (work->msk) {
work->msk = 0;
smp_call_function_interrupt();
}
if (work->resched) {
work->resched = 0;
smp_resched_interrupt();
}
}
static void smp4d_ipi_single(int cpu)
{
struct sun4d_ipi_work *work = &per_cpu(sun4d_ipi_work, cpu);
/* Mark work */
work->single = 1;
/* Generate IRQ on the CPU */
sun4d_send_ipi(cpu, SUN4D_IPI_IRQ);
}
static void smp4d_ipi_mask_one(int cpu)
{
struct sun4d_ipi_work *work = &per_cpu(sun4d_ipi_work, cpu);
/* Mark work */
work->msk = 1;
/* Generate IRQ on the CPU */
sun4d_send_ipi(cpu, SUN4D_IPI_IRQ);
}
static void smp4d_ipi_resched(int cpu)
{
struct sun4d_ipi_work *work = &per_cpu(sun4d_ipi_work, cpu);
/* Mark work */
work->resched = 1;
/* Generate IRQ on the CPU (any IRQ will cause resched) */
sun4d_send_ipi(cpu, SUN4D_IPI_IRQ);
}
static struct smp_funcall {
smpfunc_t func;
unsigned long arg1;
unsigned long arg2;
unsigned long arg3;
unsigned long arg4;
unsigned long arg5;
unsigned char processors_in[NR_CPUS]; /* Set when ipi entered. */
unsigned char processors_out[NR_CPUS]; /* Set when ipi exited. */
} ccall_info __attribute__((aligned(8)));
static DEFINE_SPINLOCK(cross_call_lock);
/* Cross calls must be serialized, at least currently. */
static void smp4d_cross_call(smpfunc_t func, cpumask_t mask, unsigned long arg1,
unsigned long arg2, unsigned long arg3,
unsigned long arg4)
{
if (smp_processors_ready) {
register int high = smp_highest_cpu;
unsigned long flags;
spin_lock_irqsave(&cross_call_lock, flags);
{
/*
* If you make changes here, make sure
* gcc generates proper code...
*/
register smpfunc_t f asm("i0") = func;
register unsigned long a1 asm("i1") = arg1;
register unsigned long a2 asm("i2") = arg2;
register unsigned long a3 asm("i3") = arg3;
register unsigned long a4 asm("i4") = arg4;
register unsigned long a5 asm("i5") = 0;
__asm__ __volatile__(
"std %0, [%6]\n\t"
"std %2, [%6 + 8]\n\t"
"std %4, [%6 + 16]\n\t" : :
"r"(f), "r"(a1), "r"(a2), "r"(a3), "r"(a4), "r"(a5),
"r" (&ccall_info.func));
}
/* Init receive/complete mapping, plus fire the IPI's off. */
{
register int i;
cpumask_clear_cpu(smp_processor_id(), &mask);
cpumask_and(&mask, cpu_online_mask, &mask);
for (i = 0; i <= high; i++) {
if (cpumask_test_cpu(i, &mask)) {
ccall_info.processors_in[i] = 0;
ccall_info.processors_out[i] = 0;
sun4d_send_ipi(i, IRQ_CROSS_CALL);
}
}
}
{
register int i;
i = 0;
do {
if (!cpumask_test_cpu(i, &mask))
continue;
while (!ccall_info.processors_in[i])
barrier();
} while (++i <= high);
i = 0;
do {
if (!cpumask_test_cpu(i, &mask))
continue;
while (!ccall_info.processors_out[i])
barrier();
} while (++i <= high);
}
spin_unlock_irqrestore(&cross_call_lock, flags);
}
}
/* Running cross calls. */
void smp4d_cross_call_irq(void)
{
int i = hard_smp_processor_id();
ccall_info.processors_in[i] = 1;
ccall_info.func(ccall_info.arg1, ccall_info.arg2, ccall_info.arg3,
ccall_info.arg4, ccall_info.arg5);
ccall_info.processors_out[i] = 1;
}
void smp4d_percpu_timer_interrupt(struct pt_regs *regs)
{
struct pt_regs *old_regs;
int cpu = hard_smp_processor_id();
struct clock_event_device *ce;
static int cpu_tick[NR_CPUS];
static char led_mask[] = { 0xe, 0xd, 0xb, 0x7, 0xb, 0xd };
old_regs = set_irq_regs(regs);
bw_get_prof_limit(cpu);
bw_clear_intr_mask(0, 1); /* INTR_TABLE[0] & 1 is Profile IRQ */
cpu_tick[cpu]++;
if (!(cpu_tick[cpu] & 15)) {
if (cpu_tick[cpu] == 0x60)
cpu_tick[cpu] = 0;
cpu_leds[cpu] = led_mask[cpu_tick[cpu] >> 4];
show_leds(cpu);
}
ce = &per_cpu(sparc32_clockevent, cpu);
irq_enter();
ce->event_handler(ce);
irq_exit();
set_irq_regs(old_regs);
}
void __init sun4d_init_smp(void)
{
int i;
/* Patch ipi15 trap table */
t_nmi[1] = t_nmi[1] + (linux_trap_ipi15_sun4d - linux_trap_ipi15_sun4m);
/* And set btfixup... */
BTFIXUPSET_CALL(smp_cross_call, smp4d_cross_call, BTFIXUPCALL_NORM);
BTFIXUPSET_CALL(smp_ipi_resched, smp4d_ipi_resched, BTFIXUPCALL_NORM);
BTFIXUPSET_CALL(smp_ipi_single, smp4d_ipi_single, BTFIXUPCALL_NORM);
BTFIXUPSET_CALL(smp_ipi_mask_one, smp4d_ipi_mask_one, BTFIXUPCALL_NORM);
for (i = 0; i < NR_CPUS; i++) {
ccall_info.processors_in[i] = 1;
ccall_info.processors_out[i] = 1;
}
}