original_kernel/arch/powerpc/platforms/wsp/smp.c

89 lines
2.0 KiB
C

/*
* SMP Support for A2 platforms
*
* Copyright 2007 Benjamin Herrenschmidt, IBM Corp.
*
* 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.
*
*/
#include <linux/cpumask.h>
#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/of.h>
#include <linux/smp.h>
#include <asm/dbell.h>
#include <asm/machdep.h>
#include <asm/xics.h>
#include "ics.h"
#include "wsp.h"
static void __devinit smp_a2_setup_cpu(int cpu)
{
doorbell_setup_this_cpu();
if (cpu != boot_cpuid)
xics_setup_cpu();
}
int __devinit smp_a2_kick_cpu(int nr)
{
const char *enable_method;
struct device_node *np;
int thr_idx;
if (nr < 0 || nr >= NR_CPUS)
return -ENOENT;
np = of_get_cpu_node(nr, &thr_idx);
if (!np)
return -ENODEV;
enable_method = of_get_property(np, "enable-method", NULL);
pr_devel("CPU%d has enable-method: \"%s\"\n", nr, enable_method);
if (!enable_method) {
printk(KERN_ERR "CPU%d has no enable-method\n", nr);
return -ENOENT;
} else if (strcmp(enable_method, "ibm,a2-scom") == 0) {
if (a2_scom_startup_cpu(nr, thr_idx, np))
return -1;
} else {
printk(KERN_ERR "CPU%d: Don't understand enable-method \"%s\"\n",
nr, enable_method);
return -EINVAL;
}
/*
* 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;
return 0;
}
static int __init smp_a2_probe(void)
{
return cpus_weight(cpu_possible_map);
}
static struct smp_ops_t a2_smp_ops = {
.message_pass = NULL, /* Use smp_muxed_ipi_message_pass */
.cause_ipi = doorbell_cause_ipi,
.probe = smp_a2_probe,
.kick_cpu = smp_a2_kick_cpu,
.setup_cpu = smp_a2_setup_cpu,
};
void __init a2_setup_smp(void)
{
smp_ops = &a2_smp_ops;
}