| Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame^] | 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 <asm/io.h> |
| 10 | #include <asm/kdebug.h> |
| 11 | #include <asm/delay.h> |
| 12 | #include <asm/hw_irq.h> |
| 13 | #include <asm/system.h> |
| 14 | #include <asm/pgtable.h> |
| 15 | #include <asm/tlbflush.h> |
| 16 | #include <asm/apic.h> |
| 17 | |
| 18 | /* |
| 19 | * Power off function, if any |
| 20 | */ |
| 21 | void (*pm_power_off)(void); |
| 22 | |
| 23 | static long no_idt[3]; |
| 24 | static enum { |
| 25 | BOOT_TRIPLE = 't', |
| 26 | BOOT_KBD = 'k' |
| 27 | } reboot_type = BOOT_KBD; |
| 28 | static int reboot_mode = 0; |
| 29 | int reboot_force; |
| 30 | |
| 31 | /* reboot=t[riple] | k[bd] [, [w]arm | [c]old] |
| 32 | warm Don't set the cold reboot flag |
| 33 | cold Set the cold reboot flag |
| 34 | triple Force a triple fault (init) |
| 35 | kbd Use the keyboard controller. cold reset (default) |
| 36 | force Avoid anything that could hang. |
| 37 | */ |
| 38 | static int __init reboot_setup(char *str) |
| 39 | { |
| 40 | for (;;) { |
| 41 | switch (*str) { |
| 42 | case 'w': |
| 43 | reboot_mode = 0x1234; |
| 44 | break; |
| 45 | |
| 46 | case 'c': |
| 47 | reboot_mode = 0; |
| 48 | break; |
| 49 | |
| 50 | case 't': |
| 51 | case 'b': |
| 52 | case 'k': |
| 53 | reboot_type = *str; |
| 54 | break; |
| 55 | case 'f': |
| 56 | reboot_force = 1; |
| 57 | break; |
| 58 | } |
| 59 | if((str = strchr(str,',')) != NULL) |
| 60 | str++; |
| 61 | else |
| 62 | break; |
| 63 | } |
| 64 | return 1; |
| 65 | } |
| 66 | |
| 67 | __setup("reboot=", reboot_setup); |
| 68 | |
| 69 | #ifdef CONFIG_SMP |
| 70 | static void smp_halt(void) |
| 71 | { |
| 72 | int cpuid = safe_smp_processor_id(); |
| 73 | static int first_entry = 1; |
| 74 | |
| 75 | if (reboot_force) |
| 76 | return; |
| 77 | |
| 78 | if (first_entry) { |
| 79 | first_entry = 0; |
| 80 | smp_call_function((void *)machine_restart, NULL, 1, 0); |
| 81 | } |
| 82 | |
| 83 | smp_stop_cpu(); |
| 84 | |
| 85 | /* AP calling this. Just halt */ |
| 86 | if (cpuid != boot_cpu_id) { |
| 87 | for (;;) |
| 88 | asm("hlt"); |
| 89 | } |
| 90 | |
| 91 | /* Wait for all other CPUs to have run smp_stop_cpu */ |
| 92 | while (!cpus_empty(cpu_online_map)) |
| 93 | rep_nop(); |
| 94 | } |
| 95 | #endif |
| 96 | |
| 97 | static inline void kb_wait(void) |
| 98 | { |
| 99 | int i; |
| 100 | |
| 101 | for (i=0; i<0x10000; i++) |
| 102 | if ((inb_p(0x64) & 0x02) == 0) |
| 103 | break; |
| 104 | } |
| 105 | |
| 106 | void machine_restart(char * __unused) |
| 107 | { |
| 108 | int i; |
| 109 | |
| 110 | printk("machine restart\n"); |
| 111 | |
| 112 | #ifdef CONFIG_SMP |
| 113 | smp_halt(); |
| 114 | #endif |
| 115 | |
| 116 | if (!reboot_force) { |
| 117 | local_irq_disable(); |
| 118 | #ifndef CONFIG_SMP |
| 119 | disable_local_APIC(); |
| 120 | #endif |
| 121 | disable_IO_APIC(); |
| 122 | local_irq_enable(); |
| 123 | } |
| 124 | |
| 125 | /* Tell the BIOS if we want cold or warm reboot */ |
| 126 | *((unsigned short *)__va(0x472)) = reboot_mode; |
| 127 | |
| 128 | for (;;) { |
| 129 | /* Could also try the reset bit in the Hammer NB */ |
| 130 | switch (reboot_type) { |
| 131 | case BOOT_KBD: |
| 132 | for (i=0; i<100; i++) { |
| 133 | kb_wait(); |
| 134 | udelay(50); |
| 135 | outb(0xfe,0x64); /* pulse reset low */ |
| 136 | udelay(50); |
| 137 | } |
| 138 | |
| 139 | case BOOT_TRIPLE: |
| 140 | __asm__ __volatile__("lidt (%0)": :"r" (&no_idt)); |
| 141 | __asm__ __volatile__("int3"); |
| 142 | |
| 143 | reboot_type = BOOT_KBD; |
| 144 | break; |
| 145 | } |
| 146 | } |
| 147 | } |
| 148 | |
| 149 | EXPORT_SYMBOL(machine_restart); |
| 150 | |
| 151 | void machine_halt(void) |
| 152 | { |
| 153 | } |
| 154 | |
| 155 | EXPORT_SYMBOL(machine_halt); |
| 156 | |
| 157 | void machine_power_off(void) |
| 158 | { |
| 159 | if (pm_power_off) |
| 160 | pm_power_off(); |
| 161 | } |
| 162 | |
| 163 | EXPORT_SYMBOL(machine_power_off); |