blob: 84bd6fde7a7c835db555af4c4a982bacb527c0a6 [file] [log] [blame]
/*
* linux/arch/arm/mach-vexpress/platsmp.c
*
* Copyright (C) 2002 ARM Ltd.
* All Rights Reserved
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*/
#include <linux/init.h>
#include <linux/errno.h>
#include <linux/smp.h>
#include <linux/io.h>
#include <linux/of_fdt.h>
#include <linux/vexpress.h>
#include <asm/smp_scu.h>
#include <asm/mach/map.h>
#include <mach/motherboard.h>
#include <plat/platsmp.h>
#include "core.h"
#if defined(CONFIG_OF)
static enum {
GENERIC_SCU,
CORTEX_A9_SCU,
} vexpress_dt_scu __initdata = GENERIC_SCU;
static struct map_desc vexpress_dt_cortex_a9_scu_map __initdata = {
.virtual = V2T_PERIPH,
/* .pfn set in vexpress_dt_init_cortex_a9_scu() */
.length = SZ_128,
.type = MT_DEVICE,
};
static void *vexpress_dt_cortex_a9_scu_base __initdata;
const static char *vexpress_dt_cortex_a9_match[] __initconst = {
"arm,cortex-a5-scu",
"arm,cortex-a9-scu",
NULL
};
static int __init vexpress_dt_find_scu(unsigned long node,
const char *uname, int depth, void *data)
{
if (of_flat_dt_match(node, vexpress_dt_cortex_a9_match)) {
phys_addr_t phys_addr;
const __be32 *reg = of_get_flat_dt_prop(node, "reg", NULL);
if (WARN_ON(!reg))
return -EINVAL;
phys_addr = be32_to_cpup(reg);
vexpress_dt_scu = CORTEX_A9_SCU;
vexpress_dt_cortex_a9_scu_map.pfn = __phys_to_pfn(phys_addr);
iotable_init(&vexpress_dt_cortex_a9_scu_map, 1);
vexpress_dt_cortex_a9_scu_base = ioremap(phys_addr, SZ_256);
if (WARN_ON(!vexpress_dt_cortex_a9_scu_base))
return -EFAULT;
}
return 0;
}
void __init vexpress_dt_smp_map_io(void)
{
if (initial_boot_params)
WARN_ON(of_scan_flat_dt(vexpress_dt_find_scu, NULL));
}
static int __init vexpress_dt_cpus_num(unsigned long node, const char *uname,
int depth, void *data)
{
static int prev_depth = -1;
static int nr_cpus = -1;
if (prev_depth > depth && nr_cpus > 0)
return nr_cpus;
if (nr_cpus < 0 && strcmp(uname, "cpus") == 0)
nr_cpus = 0;
if (nr_cpus >= 0) {
const char *device_type = of_get_flat_dt_prop(node,
"device_type", NULL);
if (device_type && strcmp(device_type, "cpu") == 0)
nr_cpus++;
}
prev_depth = depth;
return 0;
}
static void __init vexpress_dt_smp_init_cpus(void)
{
int ncores = 0, i;
switch (vexpress_dt_scu) {
case GENERIC_SCU:
ncores = of_scan_flat_dt(vexpress_dt_cpus_num, NULL);
break;
case CORTEX_A9_SCU:
ncores = scu_get_core_count(vexpress_dt_cortex_a9_scu_base);
break;
default:
WARN_ON(1);
break;
}
if (ncores < 2)
return;
if (ncores > nr_cpu_ids) {
pr_warn("SMP: %u cores greater than maximum (%u), clipping\n",
ncores, nr_cpu_ids);
ncores = nr_cpu_ids;
}
for (i = 0; i < ncores; ++i)
set_cpu_possible(i, true);
}
static void __init vexpress_dt_smp_prepare_cpus(unsigned int max_cpus)
{
int i;
switch (vexpress_dt_scu) {
case GENERIC_SCU:
for (i = 0; i < max_cpus; i++)
set_cpu_present(i, true);
break;
case CORTEX_A9_SCU:
scu_enable(vexpress_dt_cortex_a9_scu_base);
break;
default:
WARN_ON(1);
break;
}
}
#else
static void __init vexpress_dt_smp_init_cpus(void)
{
WARN_ON(1);
}
void __init vexpress_dt_smp_prepare_cpus(unsigned int max_cpus)
{
WARN_ON(1);
}
#endif
/*
* Initialise the CPU possible map early - this describes the CPUs
* which may be present or become present in the system.
*/
static void __init vexpress_smp_init_cpus(void)
{
if (ct_desc)
ct_desc->init_cpu_map();
else
vexpress_dt_smp_init_cpus();
}
static void __init vexpress_smp_prepare_cpus(unsigned int max_cpus)
{
/*
* Initialise the present map, which describes the set of CPUs
* actually populated at the present time.
*/
if (ct_desc)
ct_desc->smp_enable(max_cpus);
else
vexpress_dt_smp_prepare_cpus(max_cpus);
/*
* Write the address of secondary startup into the
* system-wide flags register. The boot monitor waits
* until it receives a soft interrupt, and then the
* secondary CPU branches to this address.
*/
vexpress_flags_set(virt_to_phys(versatile_secondary_startup));
}
struct smp_operations __initdata vexpress_smp_ops = {
.smp_init_cpus = vexpress_smp_init_cpus,
.smp_prepare_cpus = vexpress_smp_prepare_cpus,
.smp_secondary_init = versatile_secondary_init,
.smp_boot_secondary = versatile_boot_secondary,
#ifdef CONFIG_HOTPLUG_CPU
.cpu_die = vexpress_cpu_die,
#endif
};