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-rw-r--r--arch/x86/kernel/reboot_64.c171
1 files changed, 171 insertions, 0 deletions
diff --git a/arch/x86/kernel/reboot_64.c b/arch/x86/kernel/reboot_64.c
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index 000000000000..368db2b9c5ac
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+++ b/arch/x86/kernel/reboot_64.c
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1/* Various gunk just to reboot the machine. */
2#include <linux/module.h>
3#include <linux/reboot.h>
4#include <linux/init.h>
5#include <linux/smp.h>
6#include <linux/kernel.h>
7#include <linux/ctype.h>
8#include <linux/string.h>
9#include <linux/pm.h>
10#include <linux/kdebug.h>
11#include <linux/sched.h>
12#include <asm/io.h>
13#include <asm/delay.h>
14#include <asm/hw_irq.h>
15#include <asm/system.h>
16#include <asm/pgtable.h>
17#include <asm/tlbflush.h>
18#include <asm/apic.h>
19#include <asm/iommu.h>
20
21/*
22 * Power off function, if any
23 */
24void (*pm_power_off)(void);
25EXPORT_SYMBOL(pm_power_off);
26
27static long no_idt[3];
28static enum {
29 BOOT_TRIPLE = 't',
30 BOOT_KBD = 'k'
31} reboot_type = BOOT_KBD;
32static int reboot_mode = 0;
33int reboot_force;
34
35/* reboot=t[riple] | k[bd] [, [w]arm | [c]old]
36 warm Don't set the cold reboot flag
37 cold Set the cold reboot flag
38 triple Force a triple fault (init)
39 kbd Use the keyboard controller. cold reset (default)
40 force Avoid anything that could hang.
41 */
42static int __init reboot_setup(char *str)
43{
44 for (;;) {
45 switch (*str) {
46 case 'w':
47 reboot_mode = 0x1234;
48 break;
49
50 case 'c':
51 reboot_mode = 0;
52 break;
53
54 case 't':
55 case 'b':
56 case 'k':
57 reboot_type = *str;
58 break;
59 case 'f':
60 reboot_force = 1;
61 break;
62 }
63 if((str = strchr(str,',')) != NULL)
64 str++;
65 else
66 break;
67 }
68 return 1;
69}
70
71__setup("reboot=", reboot_setup);
72
73static inline void kb_wait(void)
74{
75 int i;
76
77 for (i=0; i<0x10000; i++)
78 if ((inb_p(0x64) & 0x02) == 0)
79 break;
80}
81
82void machine_shutdown(void)
83{
84 unsigned long flags;
85
86 /* Stop the cpus and apics */
87#ifdef CONFIG_SMP
88 int reboot_cpu_id;
89
90 /* The boot cpu is always logical cpu 0 */
91 reboot_cpu_id = 0;
92
93 /* Make certain the cpu I'm about to reboot on is online */
94 if (!cpu_isset(reboot_cpu_id, cpu_online_map)) {
95 reboot_cpu_id = smp_processor_id();
96 }
97
98 /* Make certain I only run on the appropriate processor */
99 set_cpus_allowed(current, cpumask_of_cpu(reboot_cpu_id));
100
101 /* O.K Now that I'm on the appropriate processor,
102 * stop all of the others.
103 */
104 smp_send_stop();
105#endif
106
107 local_irq_save(flags);
108
109#ifndef CONFIG_SMP
110 disable_local_APIC();
111#endif
112
113 disable_IO_APIC();
114
115 local_irq_restore(flags);
116
117 pci_iommu_shutdown();
118}
119
120void machine_emergency_restart(void)
121{
122 int i;
123
124 /* Tell the BIOS if we want cold or warm reboot */
125 *((unsigned short *)__va(0x472)) = reboot_mode;
126
127 for (;;) {
128 /* Could also try the reset bit in the Hammer NB */
129 switch (reboot_type) {
130 case BOOT_KBD:
131 for (i=0; i<10; i++) {
132 kb_wait();
133 udelay(50);
134 outb(0xfe,0x64); /* pulse reset low */
135 udelay(50);
136 }
137
138 case BOOT_TRIPLE:
139 __asm__ __volatile__("lidt (%0)": :"r" (&no_idt));
140 __asm__ __volatile__("int3");
141
142 reboot_type = BOOT_KBD;
143 break;
144 }
145 }
146}
147
148void machine_restart(char * __unused)
149{
150 printk("machine restart\n");
151
152 if (!reboot_force) {
153 machine_shutdown();
154 }
155 machine_emergency_restart();
156}
157
158void machine_halt(void)
159{
160}
161
162void machine_power_off(void)
163{
164 if (pm_power_off) {
165 if (!reboot_force) {
166 machine_shutdown();
167 }
168 pm_power_off();
169 }
170}
171