linux/arch/sparc/kernel/sun4m_smp.c
David S. Miller a9919646d1 sparc32: Kill trap table freeing code.
Normally, srmmu uses different trap table register values to allow
determination of the cpu we're on.  All of the trap tables have
identical content, they just sit at different offsets from the first
trap table, and the offset shifted down and masked out determines
the cpu we are on.

The code tries to free them up when they aren't actually used
(don't have all 4 cpus, we're on sun4d, etc.) but that causes
problems.

For one thing it triggers false positives in the DMA debugging
code.  And fixing that up while preserving this relative offset
thing isn't trivial.

So just kill the freeing code, it costs us at most 3 pages, big
deal...

Signed-off-by: David S. Miller <davem@davemloft.net>
2009-08-18 23:44:08 -07:00

356 lines
7.8 KiB
C

/* sun4m_smp.c: Sparc SUN4M SMP support.
*
* Copyright (C) 1996 David S. Miller (davem@caip.rutgers.edu)
*/
#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/swap.h>
#include <linux/profile.h>
#include <linux/delay.h>
#include <linux/cpu.h>
#include <asm/cacheflush.h>
#include <asm/tlbflush.h>
#include <asm/irq_regs.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/cpudata.h>
#include "irq.h"
#define IRQ_CROSS_CALL 15
extern ctxd_t *srmmu_ctx_table_phys;
extern volatile unsigned long cpu_callin_map[NR_CPUS];
extern unsigned char boot_cpu_id;
extern cpumask_t smp_commenced_mask;
extern int __smp4m_processor_id(void);
/*#define SMP_DEBUG*/
#ifdef SMP_DEBUG
#define SMP_PRINTK(x) printk x
#else
#define SMP_PRINTK(x)
#endif
static inline unsigned long
swap_ulong(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 smp_setup_percpu_timer(void);
extern void cpu_probe(void);
void __cpuinit smp4m_callin(void)
{
int cpuid = hard_smp_processor_id();
local_flush_cache_all();
local_flush_tlb_all();
notify_cpu_starting(cpuid);
/* Get our local ticker going. */
smp_setup_percpu_timer();
calibrate_delay();
smp_store_cpu_info(cpuid);
local_flush_cache_all();
local_flush_tlb_all();
/*
* 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.
*/
/* Allow master to continue. */
swap_ulong(&cpu_callin_map[cpuid], 1);
/* XXX: What's up with all the flushes? */
local_flush_cache_all();
local_flush_tlb_all();
cpu_probe();
/* Fix idle thread fields. */
__asm__ __volatile__("ld [%0], %%g6\n\t"
: : "r" (&current_set[cpuid])
: "memory" /* paranoid */);
/* Attach to the address space of init_task. */
atomic_inc(&init_mm.mm_count);
current->active_mm = &init_mm;
while (!cpu_isset(cpuid, smp_commenced_mask))
mb();
local_irq_enable();
set_cpu_online(cpuid, true);
}
/*
* Cycle through the processors asking the PROM to start each one.
*/
extern struct linux_prom_registers smp_penguin_ctable;
void __init smp4m_boot_cpus(void)
{
smp_setup_percpu_timer();
local_flush_cache_all();
}
int __cpuinit smp4m_boot_one_cpu(int i)
{
extern unsigned long sun4m_cpu_startup;
unsigned long *entry = &sun4m_cpu_startup;
struct task_struct *p;
int timeout;
int cpu_node;
cpu_find_by_mid(i, &cpu_node);
/* Cook up an idler for this guy. */
p = fork_idle(i);
current_set[i] = task_thread_info(p);
/* See trampoline.S for details... */
entry += ((i-1) * 3);
/*
* 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("Starting CPU %d at %p\n", i, entry);
local_flush_cache_all();
prom_startcpu(cpu_node,
&smp_penguin_ctable, 0, (char *)entry);
/* wheee... it's going... */
for(timeout = 0; timeout < 10000; timeout++) {
if(cpu_callin_map[i])
break;
udelay(200);
}
if (!(cpu_callin_map[i])) {
printk("Processor %d is stuck.\n", i);
return -ENODEV;
}
local_flush_cache_all();
return 0;
}
void __init smp4m_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_flush_cache_all();
/* Ok, they are spinning and ready to go. */
}
/* At each hardware IRQ, we get this called to forward IRQ reception
* to the next processor. The caller must disable the IRQ level being
* serviced globally so that there are no double interrupts received.
*
* XXX See sparc64 irq.c.
*/
void smp4m_irq_rotate(int cpu)
{
int next = cpu_data(cpu).next;
if (next != cpu)
set_irq_udt(next);
}
static struct smp_funcall {
smpfunc_t func;
unsigned long arg1;
unsigned long arg2;
unsigned long arg3;
unsigned long arg4;
unsigned long arg5;
unsigned long processors_in[SUN4M_NCPUS]; /* Set when ipi entered. */
unsigned long processors_out[SUN4M_NCPUS]; /* Set when ipi exited. */
} ccall_info;
static DEFINE_SPINLOCK(cross_call_lock);
/* Cross calls must be serialized, at least currently. */
static void smp4m_cross_call(smpfunc_t func, cpumask_t mask, unsigned long arg1,
unsigned long arg2, unsigned long arg3,
unsigned long arg4)
{
register int ncpus = SUN4M_NCPUS;
unsigned long flags;
spin_lock_irqsave(&cross_call_lock, flags);
/* Init function glue. */
ccall_info.func = func;
ccall_info.arg1 = arg1;
ccall_info.arg2 = arg2;
ccall_info.arg3 = arg3;
ccall_info.arg4 = arg4;
ccall_info.arg5 = 0;
/* Init receive/complete mapping, plus fire the IPI's off. */
{
register int i;
cpu_clear(smp_processor_id(), mask);
cpus_and(mask, cpu_online_map, mask);
for(i = 0; i < ncpus; i++) {
if (cpu_isset(i, mask)) {
ccall_info.processors_in[i] = 0;
ccall_info.processors_out[i] = 0;
set_cpu_int(i, IRQ_CROSS_CALL);
} else {
ccall_info.processors_in[i] = 1;
ccall_info.processors_out[i] = 1;
}
}
}
{
register int i;
i = 0;
do {
if (!cpu_isset(i, mask))
continue;
while(!ccall_info.processors_in[i])
barrier();
} while(++i < ncpus);
i = 0;
do {
if (!cpu_isset(i, mask))
continue;
while(!ccall_info.processors_out[i])
barrier();
} while(++i < ncpus);
}
spin_unlock_irqrestore(&cross_call_lock, flags);
}
/* Running cross calls. */
void smp4m_cross_call_irq(void)
{
int i = 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;
}
extern void sun4m_clear_profile_irq(int cpu);
void smp4m_percpu_timer_interrupt(struct pt_regs *regs)
{
struct pt_regs *old_regs;
int cpu = smp_processor_id();
old_regs = set_irq_regs(regs);
sun4m_clear_profile_irq(cpu);
profile_tick(CPU_PROFILING);
if(!--prof_counter(cpu)) {
int user = user_mode(regs);
irq_enter();
update_process_times(user);
irq_exit();
prof_counter(cpu) = prof_multiplier(cpu);
}
set_irq_regs(old_regs);
}
extern unsigned int lvl14_resolution;
static void __cpuinit smp_setup_percpu_timer(void)
{
int cpu = smp_processor_id();
prof_counter(cpu) = prof_multiplier(cpu) = 1;
load_profile_irq(cpu, lvl14_resolution);
if(cpu == boot_cpu_id)
enable_pil_irq(14);
}
static void __init smp4m_blackbox_id(unsigned *addr)
{
int rd = *addr & 0x3e000000;
int rs1 = rd >> 11;
addr[0] = 0x81580000 | rd; /* rd %tbr, reg */
addr[1] = 0x8130200c | rd | rs1; /* srl reg, 0xc, reg */
addr[2] = 0x80082003 | rd | rs1; /* and reg, 3, reg */
}
static void __init smp4m_blackbox_current(unsigned *addr)
{
int rd = *addr & 0x3e000000;
int rs1 = rd >> 11;
addr[0] = 0x81580000 | rd; /* rd %tbr, reg */
addr[2] = 0x8130200a | rd | rs1; /* srl reg, 0xa, reg */
addr[4] = 0x8008200c | rd | rs1; /* and reg, 0xc, reg */
}
void __init sun4m_init_smp(void)
{
BTFIXUPSET_BLACKBOX(hard_smp_processor_id, smp4m_blackbox_id);
BTFIXUPSET_BLACKBOX(load_current, smp4m_blackbox_current);
BTFIXUPSET_CALL(smp_cross_call, smp4m_cross_call, BTFIXUPCALL_NORM);
BTFIXUPSET_CALL(__hard_smp_processor_id, __smp4m_processor_id, BTFIXUPCALL_NORM);
}