smp_32.c

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/* smp.c: Sparc SMP support.
 *
 * Copyright (C) 1996 David S. Miller ([email protected])
 * Copyright (C) 1998 Jakub Jelinek ([email protected])
 * Copyright (C) 2004 Keith M Wesolowski ([email protected])
 */

#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 <linux/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;

const struct sparc32_ipi_ops *sparc32_ipi_ops;

/* 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;
    int mid;

    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;
    mid = cpu_get_hwmid(cpu_node);

    if (mid < 0) {
        printk(KERN_NOTICE "No MID found for CPU%d at node 0x%08d", id, cpu_node);
        mid = 0;
    }
    cpu_data(id).mid = mid;
}

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 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.
     */
    sparc32_ipi_ops->resched(cpu);
}

void smp_send_stop(void)
{
}

void arch_send_call_function_single_ipi(int cpu)
{
    /* trigger one IPI single call on one CPU */
    sparc32_ipi_ops->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)
        sparc32_ipi_ops->mask_one(cpu);
}

void smp_resched_interrupt(void)
{
    irq_enter();
    scheduler_ipi();
    local_cpu_data().irq_resched_count++;
    irq_exit();
    /* 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();
}

int setup_profiling_timer(unsigned int multiplier)
{
    return -EINVAL;
}

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 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, struct task_struct *tidle)
{
    extern int __cpuinit smp4m_boot_one_cpu(int, struct task_struct *);
    extern int __cpuinit smp4d_boot_one_cpu(int, struct task_struct *);
    int ret=0;

    switch(sparc_cpu_model) {
    case sun4m:
        ret = smp4m_boot_one_cpu(cpu, tidle);
        break;
    case sun4d:
        ret = smp4d_boot_one_cpu(cpu, tidle);
        break;
    case sparc_leon:
        ret = leon_boot_one_cpu(cpu, tidle);
        break;
    case sun4e:
        printk("SUN4E\n");
        BUG();
        break;
    case sun4u:
        printk("SUN4U\n");
        BUG();
        break;
    default:
        printk("UNKNOWN!\n");
        BUG();
        break;
    }

    if (!ret) {
        cpumask_set_cpu(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);
}