156 строки
4.2 KiB
C
156 строки
4.2 KiB
C
/*
|
|
* Copyright (C) 1996-2000 Russell King - Converted to ARM.
|
|
* Original Copyright (C) 1995 Linus Torvalds
|
|
*
|
|
* 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/cpu.h>
|
|
#include <linux/delay.h>
|
|
#include <linux/reboot.h>
|
|
|
|
#include <asm/cacheflush.h>
|
|
#include <asm/idmap.h>
|
|
|
|
#include "reboot.h"
|
|
|
|
typedef void (*phys_reset_t)(unsigned long);
|
|
|
|
/*
|
|
* Function pointers to optional machine specific functions
|
|
*/
|
|
void (*arm_pm_restart)(enum reboot_mode reboot_mode, const char *cmd);
|
|
void (*pm_power_off)(void);
|
|
EXPORT_SYMBOL(pm_power_off);
|
|
|
|
/*
|
|
* A temporary stack to use for CPU reset. This is static so that we
|
|
* don't clobber it with the identity mapping. When running with this
|
|
* stack, any references to the current task *will not work* so you
|
|
* should really do as little as possible before jumping to your reset
|
|
* code.
|
|
*/
|
|
static u64 soft_restart_stack[16];
|
|
|
|
static void __soft_restart(void *addr)
|
|
{
|
|
phys_reset_t phys_reset;
|
|
|
|
/* Take out a flat memory mapping. */
|
|
setup_mm_for_reboot();
|
|
|
|
/* Clean and invalidate caches */
|
|
flush_cache_all();
|
|
|
|
/* Turn off caching */
|
|
cpu_proc_fin();
|
|
|
|
/* Push out any further dirty data, and ensure cache is empty */
|
|
flush_cache_all();
|
|
|
|
/* Switch to the identity mapping. */
|
|
phys_reset = (phys_reset_t)(unsigned long)virt_to_idmap(cpu_reset);
|
|
phys_reset((unsigned long)addr);
|
|
|
|
/* Should never get here. */
|
|
BUG();
|
|
}
|
|
|
|
void _soft_restart(unsigned long addr, bool disable_l2)
|
|
{
|
|
u64 *stack = soft_restart_stack + ARRAY_SIZE(soft_restart_stack);
|
|
|
|
/* Disable interrupts first */
|
|
raw_local_irq_disable();
|
|
local_fiq_disable();
|
|
|
|
/* Disable the L2 if we're the last man standing. */
|
|
if (disable_l2)
|
|
outer_disable();
|
|
|
|
/* Change to the new stack and continue with the reset. */
|
|
call_with_stack(__soft_restart, (void *)addr, (void *)stack);
|
|
|
|
/* Should never get here. */
|
|
BUG();
|
|
}
|
|
|
|
void soft_restart(unsigned long addr)
|
|
{
|
|
_soft_restart(addr, num_online_cpus() == 1);
|
|
}
|
|
|
|
/*
|
|
* Called by kexec, immediately prior to machine_kexec().
|
|
*
|
|
* This must completely disable all secondary CPUs; simply causing those CPUs
|
|
* to execute e.g. a RAM-based pin loop is not sufficient. This allows the
|
|
* kexec'd kernel to use any and all RAM as it sees fit, without having to
|
|
* avoid any code or data used by any SW CPU pin loop. The CPU hotplug
|
|
* functionality embodied in disable_nonboot_cpus() to achieve this.
|
|
*/
|
|
void machine_shutdown(void)
|
|
{
|
|
disable_nonboot_cpus();
|
|
}
|
|
|
|
/*
|
|
* Halting simply requires that the secondary CPUs stop performing any
|
|
* activity (executing tasks, handling interrupts). smp_send_stop()
|
|
* achieves this.
|
|
*/
|
|
void machine_halt(void)
|
|
{
|
|
local_irq_disable();
|
|
smp_send_stop();
|
|
|
|
local_irq_disable();
|
|
while (1);
|
|
}
|
|
|
|
/*
|
|
* Power-off simply requires that the secondary CPUs stop performing any
|
|
* activity (executing tasks, handling interrupts). smp_send_stop()
|
|
* achieves this. When the system power is turned off, it will take all CPUs
|
|
* with it.
|
|
*/
|
|
void machine_power_off(void)
|
|
{
|
|
local_irq_disable();
|
|
smp_send_stop();
|
|
|
|
if (pm_power_off)
|
|
pm_power_off();
|
|
}
|
|
|
|
/*
|
|
* Restart requires that the secondary CPUs stop performing any activity
|
|
* while the primary CPU resets the system. Systems with a single CPU can
|
|
* use soft_restart() as their machine descriptor's .restart hook, since that
|
|
* will cause the only available CPU to reset. Systems with multiple CPUs must
|
|
* provide a HW restart implementation, to ensure that all CPUs reset at once.
|
|
* This is required so that any code running after reset on the primary CPU
|
|
* doesn't have to co-ordinate with other CPUs to ensure they aren't still
|
|
* executing pre-reset code, and using RAM that the primary CPU's code wishes
|
|
* to use. Implementing such co-ordination would be essentially impossible.
|
|
*/
|
|
void machine_restart(char *cmd)
|
|
{
|
|
local_irq_disable();
|
|
smp_send_stop();
|
|
|
|
if (arm_pm_restart)
|
|
arm_pm_restart(reboot_mode, cmd);
|
|
else
|
|
do_kernel_restart(cmd);
|
|
|
|
/* Give a grace period for failure to restart of 1s */
|
|
mdelay(1000);
|
|
|
|
/* Whoops - the platform was unable to reboot. Tell the user! */
|
|
printk("Reboot failed -- System halted\n");
|
|
local_irq_disable();
|
|
while (1);
|
|
}
|