linux-stable-rt/arch/powerpc/platforms/85xx/smp.c

252 lines
6.1 KiB
C

/*
* Author: Andy Fleming <afleming@freescale.com>
* Kumar Gala <galak@kernel.crashing.org>
*
* Copyright 2006-2008 Freescale Semiconductor Inc.
*
* 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/stddef.h>
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/delay.h>
#include <linux/of.h>
#include <linux/kexec.h>
#include <linux/highmem.h>
#include <asm/machdep.h>
#include <asm/pgtable.h>
#include <asm/page.h>
#include <asm/mpic.h>
#include <asm/cacheflush.h>
#include <asm/dbell.h>
#include <sysdev/fsl_soc.h>
#include <sysdev/mpic.h>
extern void __early_start(void);
#define BOOT_ENTRY_ADDR_UPPER 0
#define BOOT_ENTRY_ADDR_LOWER 1
#define BOOT_ENTRY_R3_UPPER 2
#define BOOT_ENTRY_R3_LOWER 3
#define BOOT_ENTRY_RESV 4
#define BOOT_ENTRY_PIR 5
#define BOOT_ENTRY_R6_UPPER 6
#define BOOT_ENTRY_R6_LOWER 7
#define NUM_BOOT_ENTRY 8
#define SIZE_BOOT_ENTRY (NUM_BOOT_ENTRY * sizeof(u32))
static int __init
smp_85xx_kick_cpu(int nr)
{
unsigned long flags;
const u64 *cpu_rel_addr;
__iomem u32 *bptr_vaddr;
struct device_node *np;
int n = 0;
int ioremappable;
WARN_ON (nr < 0 || nr >= NR_CPUS);
pr_debug("smp_85xx_kick_cpu: kick CPU #%d\n", nr);
np = of_get_cpu_node(nr, NULL);
cpu_rel_addr = of_get_property(np, "cpu-release-addr", NULL);
if (cpu_rel_addr == NULL) {
printk(KERN_ERR "No cpu-release-addr for cpu %d\n", nr);
return -ENOENT;
}
/*
* A secondary core could be in a spinloop in the bootpage
* (0xfffff000), somewhere in highmem, or somewhere in lowmem.
* The bootpage and highmem can be accessed via ioremap(), but
* we need to directly access the spinloop if its in lowmem.
*/
ioremappable = *cpu_rel_addr > virt_to_phys(high_memory);
/* Map the spin table */
if (ioremappable)
bptr_vaddr = ioremap(*cpu_rel_addr, SIZE_BOOT_ENTRY);
else
bptr_vaddr = phys_to_virt(*cpu_rel_addr);
local_irq_save(flags);
out_be32(bptr_vaddr + BOOT_ENTRY_PIR, nr);
#ifdef CONFIG_PPC32
out_be32(bptr_vaddr + BOOT_ENTRY_ADDR_LOWER, __pa(__early_start));
if (!ioremappable)
flush_dcache_range((ulong)bptr_vaddr,
(ulong)(bptr_vaddr + SIZE_BOOT_ENTRY));
/* Wait a bit for the CPU to ack. */
while ((__secondary_hold_acknowledge != nr) && (++n < 1000))
mdelay(1);
#else
smp_generic_kick_cpu(nr);
out_be64((u64 *)(bptr_vaddr + BOOT_ENTRY_ADDR_UPPER),
__pa((u64)*((unsigned long long *) generic_secondary_smp_init)));
if (!ioremappable)
flush_dcache_range((ulong)bptr_vaddr,
(ulong)(bptr_vaddr + SIZE_BOOT_ENTRY));
#endif
local_irq_restore(flags);
if (ioremappable)
iounmap(bptr_vaddr);
pr_debug("waited %d msecs for CPU #%d.\n", n, nr);
return 0;
}
static void __init
smp_85xx_setup_cpu(int cpu_nr)
{
mpic_setup_this_cpu();
if (cpu_has_feature(CPU_FTR_DBELL))
doorbell_setup_this_cpu();
}
struct smp_ops_t smp_85xx_ops = {
.kick_cpu = smp_85xx_kick_cpu,
#ifdef CONFIG_KEXEC
.give_timebase = smp_generic_give_timebase,
.take_timebase = smp_generic_take_timebase,
#endif
};
#ifdef CONFIG_KEXEC
atomic_t kexec_down_cpus = ATOMIC_INIT(0);
void mpc85xx_smp_kexec_cpu_down(int crash_shutdown, int secondary)
{
local_irq_disable();
if (secondary) {
atomic_inc(&kexec_down_cpus);
/* loop forever */
while (1);
}
}
static void mpc85xx_smp_kexec_down(void *arg)
{
if (ppc_md.kexec_cpu_down)
ppc_md.kexec_cpu_down(0,1);
}
static void map_and_flush(unsigned long paddr)
{
struct page *page = pfn_to_page(paddr >> PAGE_SHIFT);
unsigned long kaddr = (unsigned long)kmap(page);
flush_dcache_range(kaddr, kaddr + PAGE_SIZE);
kunmap(page);
}
/**
* Before we reset the other cores, we need to flush relevant cache
* out to memory so we don't get anything corrupted, some of these flushes
* are performed out of an overabundance of caution as interrupts are not
* disabled yet and we can switch cores
*/
static void mpc85xx_smp_flush_dcache_kexec(struct kimage *image)
{
kimage_entry_t *ptr, entry;
unsigned long paddr;
int i;
if (image->type == KEXEC_TYPE_DEFAULT) {
/* normal kexec images are stored in temporary pages */
for (ptr = &image->head; (entry = *ptr) && !(entry & IND_DONE);
ptr = (entry & IND_INDIRECTION) ?
phys_to_virt(entry & PAGE_MASK) : ptr + 1) {
if (!(entry & IND_DESTINATION)) {
map_and_flush(entry);
}
}
/* flush out last IND_DONE page */
map_and_flush(entry);
} else {
/* crash type kexec images are copied to the crash region */
for (i = 0; i < image->nr_segments; i++) {
struct kexec_segment *seg = &image->segment[i];
for (paddr = seg->mem; paddr < seg->mem + seg->memsz;
paddr += PAGE_SIZE) {
map_and_flush(paddr);
}
}
}
/* also flush the kimage struct to be passed in as well */
flush_dcache_range((unsigned long)image,
(unsigned long)image + sizeof(*image));
}
static void mpc85xx_smp_machine_kexec(struct kimage *image)
{
int timeout = INT_MAX;
int i, num_cpus = num_present_cpus();
mpc85xx_smp_flush_dcache_kexec(image);
if (image->type == KEXEC_TYPE_DEFAULT)
smp_call_function(mpc85xx_smp_kexec_down, NULL, 0);
while ( (atomic_read(&kexec_down_cpus) != (num_cpus - 1)) &&
( timeout > 0 ) )
{
timeout--;
}
if ( !timeout )
printk(KERN_ERR "Unable to bring down secondary cpu(s)");
for (i = 0; i < num_cpus; i++)
{
if ( i == smp_processor_id() ) continue;
mpic_reset_core(i);
}
default_machine_kexec(image);
}
#endif /* CONFIG_KEXEC */
void __init mpc85xx_smp_init(void)
{
struct device_node *np;
np = of_find_node_by_type(NULL, "open-pic");
if (np) {
smp_85xx_ops.probe = smp_mpic_probe;
smp_85xx_ops.setup_cpu = smp_85xx_setup_cpu;
smp_85xx_ops.message_pass = smp_mpic_message_pass;
}
if (cpu_has_feature(CPU_FTR_DBELL)) {
smp_85xx_ops.message_pass = smp_muxed_ipi_message_pass;
smp_85xx_ops.cause_ipi = doorbell_cause_ipi;
}
BUG_ON(!smp_85xx_ops.message_pass);
smp_ops = &smp_85xx_ops;
#ifdef CONFIG_KEXEC
ppc_md.kexec_cpu_down = mpc85xx_smp_kexec_cpu_down;
ppc_md.machine_kexec = mpc85xx_smp_machine_kexec;
#endif
}