linux/arch/x86_64/kernel/reboot.c

164 lines
2.8 KiB
C

/* Various gunk just to reboot the machine. */
#include <linux/module.h>
#include <linux/reboot.h>
#include <linux/init.h>
#include <linux/smp.h>
#include <linux/kernel.h>
#include <linux/ctype.h>
#include <linux/string.h>
#include <asm/io.h>
#include <asm/kdebug.h>
#include <asm/delay.h>
#include <asm/hw_irq.h>
#include <asm/system.h>
#include <asm/pgtable.h>
#include <asm/tlbflush.h>
#include <asm/apic.h>
/*
* Power off function, if any
*/
void (*pm_power_off)(void);
static long no_idt[3];
static enum {
BOOT_TRIPLE = 't',
BOOT_KBD = 'k'
} reboot_type = BOOT_KBD;
static int reboot_mode = 0;
int reboot_force;
/* reboot=t[riple] | k[bd] [, [w]arm | [c]old]
warm Don't set the cold reboot flag
cold Set the cold reboot flag
triple Force a triple fault (init)
kbd Use the keyboard controller. cold reset (default)
force Avoid anything that could hang.
*/
static int __init reboot_setup(char *str)
{
for (;;) {
switch (*str) {
case 'w':
reboot_mode = 0x1234;
break;
case 'c':
reboot_mode = 0;
break;
case 't':
case 'b':
case 'k':
reboot_type = *str;
break;
case 'f':
reboot_force = 1;
break;
}
if((str = strchr(str,',')) != NULL)
str++;
else
break;
}
return 1;
}
__setup("reboot=", reboot_setup);
#ifdef CONFIG_SMP
static void smp_halt(void)
{
int cpuid = safe_smp_processor_id();
static int first_entry = 1;
if (reboot_force)
return;
if (first_entry) {
first_entry = 0;
smp_call_function((void *)machine_restart, NULL, 1, 0);
}
smp_stop_cpu();
/* AP calling this. Just halt */
if (cpuid != boot_cpu_id) {
for (;;)
asm("hlt");
}
/* Wait for all other CPUs to have run smp_stop_cpu */
while (!cpus_empty(cpu_online_map))
rep_nop();
}
#endif
static inline void kb_wait(void)
{
int i;
for (i=0; i<0x10000; i++)
if ((inb_p(0x64) & 0x02) == 0)
break;
}
void machine_restart(char * __unused)
{
int i;
printk("machine restart\n");
#ifdef CONFIG_SMP
smp_halt();
#endif
if (!reboot_force) {
local_irq_disable();
#ifndef CONFIG_SMP
disable_local_APIC();
#endif
disable_IO_APIC();
local_irq_enable();
}
/* Tell the BIOS if we want cold or warm reboot */
*((unsigned short *)__va(0x472)) = reboot_mode;
for (;;) {
/* Could also try the reset bit in the Hammer NB */
switch (reboot_type) {
case BOOT_KBD:
for (i=0; i<100; i++) {
kb_wait();
udelay(50);
outb(0xfe,0x64); /* pulse reset low */
udelay(50);
}
case BOOT_TRIPLE:
__asm__ __volatile__("lidt (%0)": :"r" (&no_idt));
__asm__ __volatile__("int3");
reboot_type = BOOT_KBD;
break;
}
}
}
EXPORT_SYMBOL(machine_restart);
void machine_halt(void)
{
}
EXPORT_SYMBOL(machine_halt);
void machine_power_off(void)
{
if (pm_power_off)
pm_power_off();
}
EXPORT_SYMBOL(machine_power_off);