kernel-ark/arch/sparc/kernel/smp_32.c
Daniel Hellstrom ecbc42b70a sparc32, sun4m: Implemented SMP IPIs support for SUN4M machines
Implement the three IPIs (resched, single and cpu-mask) generation
and interrupt handler catch. The sun4m has 15 soft-IRQs and three
of them is used with this patch, the three IPIs was previously
implemented with the cross-call IRQ15 which does not work with
locking routines such as spinlocks because IRQ15 is NMI, it may
cause deadlock.

The IRQ trap handler code assumes (in the same spritit as the old
it seems) that hard interrupts will be generated until handled
(level), when a IRQ happens the IRQ pending register is checked
for pending soft-IRQs. When both hard and soft IRQ happens at the
same time only soft-IRQs are handled.

The old code implemented a soft-IRQ traphandler at IRQ14 which
called smp_reschedule_irq which in turn called set_need_resched.
It seems to be an old relic and is replaced with the interrupt
traphander exit code RESTORE_ALL, it calls schedule() when
appropriate.

Signed-off-by: Daniel Hellstrom <daniel@gaisler.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2011-05-16 13:07:44 -07:00

470 lines
10 KiB
C

/* smp.c: Sparc SMP support.
*
* Copyright (C) 1996 David S. Miller (davem@caip.rutgers.edu)
* Copyright (C) 1998 Jakub Jelinek (jj@sunsite.mff.cuni.cz)
* Copyright (C) 2004 Keith M Wesolowski (wesolows@foobazco.org)
*/
#include <asm/head.h>
#include <linux/kernel.h>
#include <linux/sched.h>
#include <linux/threads.h>
#include <linux/smp.h>
#include <linux/interrupt.h>
#include <linux/kernel_stat.h>
#include <linux/init.h>
#include <linux/spinlock.h>
#include <linux/mm.h>
#include <linux/fs.h>
#include <linux/seq_file.h>
#include <linux/cache.h>
#include <linux/delay.h>
#include <asm/ptrace.h>
#include <asm/atomic.h>
#include <asm/irq.h>
#include <asm/page.h>
#include <asm/pgalloc.h>
#include <asm/pgtable.h>
#include <asm/oplib.h>
#include <asm/cacheflush.h>
#include <asm/tlbflush.h>
#include <asm/cpudata.h>
#include <asm/leon.h>
#include "irq.h"
volatile unsigned long cpu_callin_map[NR_CPUS] __cpuinitdata = {0,};
cpumask_t smp_commenced_mask = CPU_MASK_NONE;
/* The only guaranteed locking primitive available on all Sparc
* processors is 'ldstub [%reg + immediate], %dest_reg' which atomically
* places the current byte at the effective address into dest_reg and
* places 0xff there afterwards. Pretty lame locking primitive
* compared to the Alpha and the Intel no? Most Sparcs have 'swap'
* instruction which is much better...
*/
void __cpuinit smp_store_cpu_info(int id)
{
int cpu_node;
cpu_data(id).udelay_val = loops_per_jiffy;
cpu_find_by_mid(id, &cpu_node);
cpu_data(id).clock_tick = prom_getintdefault(cpu_node,
"clock-frequency", 0);
cpu_data(id).prom_node = cpu_node;
cpu_data(id).mid = cpu_get_hwmid(cpu_node);
if (cpu_data(id).mid < 0)
panic("No MID found for CPU%d at node 0x%08d", id, cpu_node);
}
void __init smp_cpus_done(unsigned int max_cpus)
{
extern void smp4m_smp_done(void);
extern void smp4d_smp_done(void);
unsigned long bogosum = 0;
int cpu, num = 0;
for_each_online_cpu(cpu) {
num++;
bogosum += cpu_data(cpu).udelay_val;
}
printk("Total of %d processors activated (%lu.%02lu BogoMIPS).\n",
num, bogosum/(500000/HZ),
(bogosum/(5000/HZ))%100);
switch(sparc_cpu_model) {
case sun4:
printk("SUN4\n");
BUG();
break;
case sun4c:
printk("SUN4C\n");
BUG();
break;
case sun4m:
smp4m_smp_done();
break;
case sun4d:
smp4d_smp_done();
break;
case sparc_leon:
leon_smp_done();
break;
case sun4e:
printk("SUN4E\n");
BUG();
break;
case sun4u:
printk("SUN4U\n");
BUG();
break;
default:
printk("UNKNOWN!\n");
BUG();
break;
};
}
void cpu_panic(void)
{
printk("CPU[%d]: Returns from cpu_idle!\n", smp_processor_id());
panic("SMP bolixed\n");
}
struct linux_prom_registers smp_penguin_ctable __cpuinitdata = { 0 };
void smp_send_reschedule(int cpu)
{
/*
* CPU model dependent way of implementing IPI generation targeting
* a single CPU. The trap handler needs only to do trap entry/return
* to call schedule.
*/
BTFIXUP_CALL(smp_ipi_resched)(cpu);
}
void smp_send_stop(void)
{
}
void arch_send_call_function_single_ipi(int cpu)
{
/* trigger one IPI single call on one CPU */
BTFIXUP_CALL(smp_ipi_single)(cpu);
}
void arch_send_call_function_ipi_mask(const struct cpumask *mask)
{
int cpu;
/* trigger IPI mask call on each CPU */
for_each_cpu(cpu, mask)
BTFIXUP_CALL(smp_ipi_mask_one)(cpu);
}
void smp_resched_interrupt(void)
{
local_cpu_data().irq_resched_count++;
/*
* do nothing, since it all was about calling re-schedule
* routine called by interrupt return code.
*/
}
void smp_call_function_single_interrupt(void)
{
irq_enter();
generic_smp_call_function_single_interrupt();
local_cpu_data().irq_call_count++;
irq_exit();
}
void smp_call_function_interrupt(void)
{
irq_enter();
generic_smp_call_function_interrupt();
local_cpu_data().irq_call_count++;
irq_exit();
}
void smp_flush_cache_all(void)
{
xc0((smpfunc_t) BTFIXUP_CALL(local_flush_cache_all));
local_flush_cache_all();
}
void smp_flush_tlb_all(void)
{
xc0((smpfunc_t) BTFIXUP_CALL(local_flush_tlb_all));
local_flush_tlb_all();
}
void smp_flush_cache_mm(struct mm_struct *mm)
{
if(mm->context != NO_CONTEXT) {
cpumask_t cpu_mask = *mm_cpumask(mm);
cpu_clear(smp_processor_id(), cpu_mask);
if (!cpus_empty(cpu_mask))
xc1((smpfunc_t) BTFIXUP_CALL(local_flush_cache_mm), (unsigned long) mm);
local_flush_cache_mm(mm);
}
}
void smp_flush_tlb_mm(struct mm_struct *mm)
{
if(mm->context != NO_CONTEXT) {
cpumask_t cpu_mask = *mm_cpumask(mm);
cpu_clear(smp_processor_id(), cpu_mask);
if (!cpus_empty(cpu_mask)) {
xc1((smpfunc_t) BTFIXUP_CALL(local_flush_tlb_mm), (unsigned long) mm);
if(atomic_read(&mm->mm_users) == 1 && current->active_mm == mm)
cpumask_copy(mm_cpumask(mm),
cpumask_of(smp_processor_id()));
}
local_flush_tlb_mm(mm);
}
}
void smp_flush_cache_range(struct vm_area_struct *vma, unsigned long start,
unsigned long end)
{
struct mm_struct *mm = vma->vm_mm;
if (mm->context != NO_CONTEXT) {
cpumask_t cpu_mask = *mm_cpumask(mm);
cpu_clear(smp_processor_id(), cpu_mask);
if (!cpus_empty(cpu_mask))
xc3((smpfunc_t) BTFIXUP_CALL(local_flush_cache_range), (unsigned long) vma, start, end);
local_flush_cache_range(vma, start, end);
}
}
void smp_flush_tlb_range(struct vm_area_struct *vma, unsigned long start,
unsigned long end)
{
struct mm_struct *mm = vma->vm_mm;
if (mm->context != NO_CONTEXT) {
cpumask_t cpu_mask = *mm_cpumask(mm);
cpu_clear(smp_processor_id(), cpu_mask);
if (!cpus_empty(cpu_mask))
xc3((smpfunc_t) BTFIXUP_CALL(local_flush_tlb_range), (unsigned long) vma, start, end);
local_flush_tlb_range(vma, start, end);
}
}
void smp_flush_cache_page(struct vm_area_struct *vma, unsigned long page)
{
struct mm_struct *mm = vma->vm_mm;
if(mm->context != NO_CONTEXT) {
cpumask_t cpu_mask = *mm_cpumask(mm);
cpu_clear(smp_processor_id(), cpu_mask);
if (!cpus_empty(cpu_mask))
xc2((smpfunc_t) BTFIXUP_CALL(local_flush_cache_page), (unsigned long) vma, page);
local_flush_cache_page(vma, page);
}
}
void smp_flush_tlb_page(struct vm_area_struct *vma, unsigned long page)
{
struct mm_struct *mm = vma->vm_mm;
if(mm->context != NO_CONTEXT) {
cpumask_t cpu_mask = *mm_cpumask(mm);
cpu_clear(smp_processor_id(), cpu_mask);
if (!cpus_empty(cpu_mask))
xc2((smpfunc_t) BTFIXUP_CALL(local_flush_tlb_page), (unsigned long) vma, page);
local_flush_tlb_page(vma, page);
}
}
void smp_flush_page_to_ram(unsigned long page)
{
/* Current theory is that those who call this are the one's
* who have just dirtied their cache with the pages contents
* in kernel space, therefore we only run this on local cpu.
*
* XXX This experiment failed, research further... -DaveM
*/
#if 1
xc1((smpfunc_t) BTFIXUP_CALL(local_flush_page_to_ram), page);
#endif
local_flush_page_to_ram(page);
}
void smp_flush_sig_insns(struct mm_struct *mm, unsigned long insn_addr)
{
cpumask_t cpu_mask = *mm_cpumask(mm);
cpu_clear(smp_processor_id(), cpu_mask);
if (!cpus_empty(cpu_mask))
xc2((smpfunc_t) BTFIXUP_CALL(local_flush_sig_insns), (unsigned long) mm, insn_addr);
local_flush_sig_insns(mm, insn_addr);
}
extern unsigned int lvl14_resolution;
/* /proc/profile writes can call this, don't __init it please. */
static DEFINE_SPINLOCK(prof_setup_lock);
int setup_profiling_timer(unsigned int multiplier)
{
int i;
unsigned long flags;
/* Prevent level14 ticker IRQ flooding. */
if((!multiplier) || (lvl14_resolution / multiplier) < 500)
return -EINVAL;
spin_lock_irqsave(&prof_setup_lock, flags);
for_each_possible_cpu(i) {
load_profile_irq(i, lvl14_resolution / multiplier);
prof_multiplier(i) = multiplier;
}
spin_unlock_irqrestore(&prof_setup_lock, flags);
return 0;
}
void __init smp_prepare_cpus(unsigned int max_cpus)
{
extern void __init smp4m_boot_cpus(void);
extern void __init smp4d_boot_cpus(void);
int i, cpuid, extra;
printk("Entering SMP Mode...\n");
extra = 0;
for (i = 0; !cpu_find_by_instance(i, NULL, &cpuid); i++) {
if (cpuid >= NR_CPUS)
extra++;
}
/* i = number of cpus */
if (extra && max_cpus > i - extra)
printk("Warning: NR_CPUS is too low to start all cpus\n");
smp_store_cpu_info(boot_cpu_id);
switch(sparc_cpu_model) {
case sun4:
printk("SUN4\n");
BUG();
break;
case sun4c:
printk("SUN4C\n");
BUG();
break;
case sun4m:
smp4m_boot_cpus();
break;
case sun4d:
smp4d_boot_cpus();
break;
case sparc_leon:
leon_boot_cpus();
break;
case sun4e:
printk("SUN4E\n");
BUG();
break;
case sun4u:
printk("SUN4U\n");
BUG();
break;
default:
printk("UNKNOWN!\n");
BUG();
break;
};
}
/* Set this up early so that things like the scheduler can init
* properly. We use the same cpu mask for both the present and
* possible cpu map.
*/
void __init smp_setup_cpu_possible_map(void)
{
int instance, mid;
instance = 0;
while (!cpu_find_by_instance(instance, NULL, &mid)) {
if (mid < NR_CPUS) {
set_cpu_possible(mid, true);
set_cpu_present(mid, true);
}
instance++;
}
}
void __init smp_prepare_boot_cpu(void)
{
int cpuid = hard_smp_processor_id();
if (cpuid >= NR_CPUS) {
prom_printf("Serious problem, boot cpu id >= NR_CPUS\n");
prom_halt();
}
if (cpuid != 0)
printk("boot cpu id != 0, this could work but is untested\n");
current_thread_info()->cpu = cpuid;
set_cpu_online(cpuid, true);
set_cpu_possible(cpuid, true);
}
int __cpuinit __cpu_up(unsigned int cpu)
{
extern int __cpuinit smp4m_boot_one_cpu(int);
extern int __cpuinit smp4d_boot_one_cpu(int);
int ret=0;
switch(sparc_cpu_model) {
case sun4:
printk("SUN4\n");
BUG();
break;
case sun4c:
printk("SUN4C\n");
BUG();
break;
case sun4m:
ret = smp4m_boot_one_cpu(cpu);
break;
case sun4d:
ret = smp4d_boot_one_cpu(cpu);
break;
case sparc_leon:
ret = leon_boot_one_cpu(cpu);
break;
case sun4e:
printk("SUN4E\n");
BUG();
break;
case sun4u:
printk("SUN4U\n");
BUG();
break;
default:
printk("UNKNOWN!\n");
BUG();
break;
};
if (!ret) {
cpu_set(cpu, smp_commenced_mask);
while (!cpu_online(cpu))
mb();
}
return ret;
}
void smp_bogo(struct seq_file *m)
{
int i;
for_each_online_cpu(i) {
seq_printf(m,
"Cpu%dBogo\t: %lu.%02lu\n",
i,
cpu_data(i).udelay_val/(500000/HZ),
(cpu_data(i).udelay_val/(5000/HZ))%100);
}
}
void smp_info(struct seq_file *m)
{
int i;
seq_printf(m, "State:\n");
for_each_online_cpu(i)
seq_printf(m, "CPU%d\t\t: online\n", i);
}