1 #include <linux/module.h>
2 #include <linux/reboot.h>
3 #include <linux/init.h>
6 #include <acpi/reboot.h>
11 #include <asm/pgtable.h>
12 #include <asm/proto.h>
13 #include <asm/reboot_fixups.h>
14 #include <asm/reboot.h>
17 # include <linux/dmi.h>
18 # include <linux/ctype.h>
19 # include <linux/mc146818rtc.h>
21 # include <asm/iommu.h>
25 * Power off function, if any
27 void (*pm_power_off)(void);
28 EXPORT_SYMBOL(pm_power_off);
30 static const struct desc_ptr no_idt = {};
31 static int reboot_mode;
32 enum reboot_type reboot_type = BOOT_KBD;
35 #if defined(CONFIG_X86_32) && defined(CONFIG_SMP)
36 static int reboot_cpu = -1;
39 /* reboot=b[ios] | s[mp] | t[riple] | k[bd] | e[fi] [, [w]arm | [c]old]
40 warm Don't set the cold reboot flag
41 cold Set the cold reboot flag
42 bios Reboot by jumping through the BIOS (only for X86_32)
43 smp Reboot by executing reset on BSP or other CPU (only for X86_32)
44 triple Force a triple fault (init)
45 kbd Use the keyboard controller. cold reset (default)
46 acpi Use the RESET_REG in the FADT
47 efi Use efi reset_system runtime service
48 force Avoid anything that could hang.
50 static int __init reboot_setup(char *str)
65 if (isdigit(*(str+1))) {
66 reboot_cpu = (int) (*(str+1) - '0');
67 if (isdigit(*(str+2)))
68 reboot_cpu = reboot_cpu*10 + (int)(*(str+2) - '0');
70 /* we will leave sorting out the final value
71 when we are ready to reboot, since we might not
72 have set up boot_cpu_id or smp_num_cpu */
74 #endif /* CONFIG_SMP */
90 str = strchr(str, ',');
99 __setup("reboot=", reboot_setup);
104 * Reboot options and system auto-detection code provided by
105 * Dell Inc. so their systems "just work". :-)
109 * Some machines require the "reboot=b" commandline option,
110 * this quirk makes that automatic.
112 static int __init set_bios_reboot(const struct dmi_system_id *d)
114 if (reboot_type != BOOT_BIOS) {
115 reboot_type = BOOT_BIOS;
116 printk(KERN_INFO "%s series board detected. Selecting BIOS-method for reboots.\n", d->ident);
121 static struct dmi_system_id __initdata reboot_dmi_table[] = {
122 { /* Handle problems with rebooting on Dell E520's */
123 .callback = set_bios_reboot,
124 .ident = "Dell E520",
126 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
127 DMI_MATCH(DMI_PRODUCT_NAME, "Dell DM061"),
130 { /* Handle problems with rebooting on Dell 1300's */
131 .callback = set_bios_reboot,
132 .ident = "Dell PowerEdge 1300",
134 DMI_MATCH(DMI_SYS_VENDOR, "Dell Computer Corporation"),
135 DMI_MATCH(DMI_PRODUCT_NAME, "PowerEdge 1300/"),
138 { /* Handle problems with rebooting on Dell 300's */
139 .callback = set_bios_reboot,
140 .ident = "Dell PowerEdge 300",
142 DMI_MATCH(DMI_SYS_VENDOR, "Dell Computer Corporation"),
143 DMI_MATCH(DMI_PRODUCT_NAME, "PowerEdge 300/"),
146 { /* Handle problems with rebooting on Dell Optiplex 745's SFF*/
147 .callback = set_bios_reboot,
148 .ident = "Dell OptiPlex 745",
150 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
151 DMI_MATCH(DMI_PRODUCT_NAME, "OptiPlex 745"),
154 { /* Handle problems with rebooting on Dell Optiplex 745's DFF*/
155 .callback = set_bios_reboot,
156 .ident = "Dell OptiPlex 745",
158 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
159 DMI_MATCH(DMI_PRODUCT_NAME, "OptiPlex 745"),
160 DMI_MATCH(DMI_BOARD_NAME, "0MM599"),
163 { /* Handle problems with rebooting on Dell Optiplex 745 with 0KW626 */
164 .callback = set_bios_reboot,
165 .ident = "Dell OptiPlex 745",
167 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
168 DMI_MATCH(DMI_PRODUCT_NAME, "OptiPlex 745"),
169 DMI_MATCH(DMI_BOARD_NAME, "0KW626"),
172 { /* Handle problems with rebooting on Dell Optiplex 360 with 0T656F */
173 .callback = set_bios_reboot,
174 .ident = "Dell OptiPlex 360",
176 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
177 DMI_MATCH(DMI_PRODUCT_NAME, "OptiPlex 360"),
178 DMI_MATCH(DMI_BOARD_NAME, "0T656F"),
181 { /* Handle problems with rebooting on Dell 2400's */
182 .callback = set_bios_reboot,
183 .ident = "Dell PowerEdge 2400",
185 DMI_MATCH(DMI_SYS_VENDOR, "Dell Computer Corporation"),
186 DMI_MATCH(DMI_PRODUCT_NAME, "PowerEdge 2400"),
189 { /* Handle problems with rebooting on Dell T5400's */
190 .callback = set_bios_reboot,
191 .ident = "Dell Precision T5400",
193 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
194 DMI_MATCH(DMI_PRODUCT_NAME, "Precision WorkStation T5400"),
197 { /* Handle problems with rebooting on HP laptops */
198 .callback = set_bios_reboot,
199 .ident = "HP Compaq Laptop",
201 DMI_MATCH(DMI_SYS_VENDOR, "Hewlett-Packard"),
202 DMI_MATCH(DMI_PRODUCT_NAME, "HP Compaq"),
205 { /* Handle problems with rebooting on Dell XPS710 */
206 .callback = set_bios_reboot,
207 .ident = "Dell XPS710",
209 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
210 DMI_MATCH(DMI_PRODUCT_NAME, "Dell XPS710"),
216 static int __init reboot_init(void)
218 dmi_check_system(reboot_dmi_table);
221 core_initcall(reboot_init);
223 /* The following code and data reboots the machine by switching to real
224 mode and jumping to the BIOS reset entry point, as if the CPU has
225 really been reset. The previous version asked the keyboard
226 controller to pulse the CPU reset line, which is more thorough, but
227 doesn't work with at least one type of 486 motherboard. It is easy
228 to stop this code working; hence the copious comments. */
229 static const unsigned long long
230 real_mode_gdt_entries [3] =
232 0x0000000000000000ULL, /* Null descriptor */
233 0x00009b000000ffffULL, /* 16-bit real-mode 64k code at 0x00000000 */
234 0x000093000100ffffULL /* 16-bit real-mode 64k data at 0x00000100 */
237 static const struct desc_ptr
238 real_mode_gdt = { sizeof (real_mode_gdt_entries) - 1, (long)real_mode_gdt_entries },
239 real_mode_idt = { 0x3ff, 0 };
241 /* This is 16-bit protected mode code to disable paging and the cache,
242 switch to real mode and jump to the BIOS reset code.
244 The instruction that switches to real mode by writing to CR0 must be
245 followed immediately by a far jump instruction, which set CS to a
246 valid value for real mode, and flushes the prefetch queue to avoid
247 running instructions that have already been decoded in protected
250 Clears all the flags except ET, especially PG (paging), PE
251 (protected-mode enable) and TS (task switch for coprocessor state
252 save). Flushes the TLB after paging has been disabled. Sets CD and
253 NW, to disable the cache on a 486, and invalidates the cache. This
254 is more like the state of a 486 after reset. I don't know if
255 something else should be done for other chips.
257 More could be done here to set up the registers as if a CPU reset had
258 occurred; hopefully real BIOSs don't assume much. */
259 static const unsigned char real_mode_switch [] =
261 0x66, 0x0f, 0x20, 0xc0, /* movl %cr0,%eax */
262 0x66, 0x83, 0xe0, 0x11, /* andl $0x00000011,%eax */
263 0x66, 0x0d, 0x00, 0x00, 0x00, 0x60, /* orl $0x60000000,%eax */
264 0x66, 0x0f, 0x22, 0xc0, /* movl %eax,%cr0 */
265 0x66, 0x0f, 0x22, 0xd8, /* movl %eax,%cr3 */
266 0x66, 0x0f, 0x20, 0xc3, /* movl %cr0,%ebx */
267 0x66, 0x81, 0xe3, 0x00, 0x00, 0x00, 0x60, /* andl $0x60000000,%ebx */
268 0x74, 0x02, /* jz f */
269 0x0f, 0x09, /* wbinvd */
270 0x24, 0x10, /* f: andb $0x10,al */
271 0x66, 0x0f, 0x22, 0xc0 /* movl %eax,%cr0 */
273 static const unsigned char jump_to_bios [] =
275 0xea, 0x00, 0x00, 0xff, 0xff /* ljmp $0xffff,$0x0000 */
279 * Switch to real mode and then execute the code
280 * specified by the code and length parameters.
281 * We assume that length will aways be less that 100!
283 void machine_real_restart(const unsigned char *code, int length)
287 /* Write zero to CMOS register number 0x0f, which the BIOS POST
288 routine will recognize as telling it to do a proper reboot. (Well
289 that's what this book in front of me says -- it may only apply to
290 the Phoenix BIOS though, it's not clear). At the same time,
291 disable NMIs by setting the top bit in the CMOS address register,
292 as we're about to do peculiar things to the CPU. I'm not sure if
293 `outb_p' is needed instead of just `outb'. Use it to be on the
294 safe side. (Yes, CMOS_WRITE does outb_p's. - Paul G.)
296 spin_lock(&rtc_lock);
297 CMOS_WRITE(0x00, 0x8f);
298 spin_unlock(&rtc_lock);
300 /* Remap the kernel at virtual address zero, as well as offset zero
301 from the kernel segment. This assumes the kernel segment starts at
302 virtual address PAGE_OFFSET. */
303 memcpy(swapper_pg_dir, swapper_pg_dir + KERNEL_PGD_BOUNDARY,
304 sizeof(swapper_pg_dir [0]) * KERNEL_PGD_PTRS);
307 * Use `swapper_pg_dir' as our page directory.
309 load_cr3(swapper_pg_dir);
311 /* Write 0x1234 to absolute memory location 0x472. The BIOS reads
312 this on booting to tell it to "Bypass memory test (also warm
313 boot)". This seems like a fairly standard thing that gets set by
314 REBOOT.COM programs, and the previous reset routine did this
316 *((unsigned short *)0x472) = reboot_mode;
318 /* For the switch to real mode, copy some code to low memory. It has
319 to be in the first 64k because it is running in 16-bit mode, and it
320 has to have the same physical and virtual address, because it turns
321 off paging. Copy it near the end of the first page, out of the way
322 of BIOS variables. */
323 memcpy((void *)(0x1000 - sizeof(real_mode_switch) - 100),
324 real_mode_switch, sizeof (real_mode_switch));
325 memcpy((void *)(0x1000 - 100), code, length);
327 /* Set up the IDT for real mode. */
328 load_idt(&real_mode_idt);
330 /* Set up a GDT from which we can load segment descriptors for real
331 mode. The GDT is not used in real mode; it is just needed here to
332 prepare the descriptors. */
333 load_gdt(&real_mode_gdt);
335 /* Load the data segment registers, and thus the descriptors ready for
336 real mode. The base address of each segment is 0x100, 16 times the
337 selector value being loaded here. This is so that the segment
338 registers don't have to be reloaded after switching to real mode:
339 the values are consistent for real mode operation already. */
340 __asm__ __volatile__ ("movl $0x0010,%%eax\n"
341 "\tmovl %%eax,%%ds\n"
342 "\tmovl %%eax,%%es\n"
343 "\tmovl %%eax,%%fs\n"
344 "\tmovl %%eax,%%gs\n"
345 "\tmovl %%eax,%%ss" : : : "eax");
347 /* Jump to the 16-bit code that we copied earlier. It disables paging
348 and the cache, switches to real mode, and jumps to the BIOS reset
350 __asm__ __volatile__ ("ljmp $0x0008,%0"
352 : "i" ((void *)(0x1000 - sizeof (real_mode_switch) - 100)));
354 #ifdef CONFIG_APM_MODULE
355 EXPORT_SYMBOL(machine_real_restart);
358 #endif /* CONFIG_X86_32 */
360 static inline void kb_wait(void)
364 for (i = 0; i < 0x10000; i++) {
365 if ((inb(0x64) & 0x02) == 0)
371 void __attribute__((weak)) mach_reboot_fixups(void)
375 static void native_machine_emergency_restart(void)
379 /* Tell the BIOS if we want cold or warm reboot */
380 *((unsigned short *)__va(0x472)) = reboot_mode;
383 /* Could also try the reset bit in the Hammer NB */
384 switch (reboot_type) {
386 mach_reboot_fixups(); /* for board specific fixups */
388 for (i = 0; i < 10; i++) {
391 outb(0xfe, 0x64); /* pulse reset low */
397 __asm__ __volatile__("int3");
399 reboot_type = BOOT_KBD;
404 machine_real_restart(jump_to_bios, sizeof(jump_to_bios));
406 reboot_type = BOOT_KBD;
412 reboot_type = BOOT_KBD;
418 efi.reset_system(reboot_mode ? EFI_RESET_WARM : EFI_RESET_COLD,
419 EFI_SUCCESS, 0, NULL);
421 reboot_type = BOOT_KBD;
427 void native_machine_shutdown(void)
429 /* Stop the cpus and apics */
432 /* The boot cpu is always logical cpu 0 */
433 int reboot_cpu_id = 0;
436 /* See if there has been given a command line override */
437 if ((reboot_cpu != -1) && (reboot_cpu < NR_CPUS) &&
438 cpu_online(reboot_cpu))
439 reboot_cpu_id = reboot_cpu;
442 /* Make certain the cpu I'm about to reboot on is online */
443 if (!cpu_online(reboot_cpu_id))
444 reboot_cpu_id = smp_processor_id();
446 /* Make certain I only run on the appropriate processor */
447 set_cpus_allowed_ptr(current, &cpumask_of_cpu(reboot_cpu_id));
449 /* O.K Now that I'm on the appropriate processor,
450 * stop all of the others.
457 #ifdef CONFIG_X86_IO_APIC
461 #ifdef CONFIG_HPET_TIMER
466 pci_iommu_shutdown();
470 static void native_machine_restart(char *__unused)
472 printk("machine restart\n");
476 machine_emergency_restart();
479 static void native_machine_halt(void)
483 static void native_machine_power_off(void)
492 struct machine_ops machine_ops = {
493 .power_off = native_machine_power_off,
494 .shutdown = native_machine_shutdown,
495 .emergency_restart = native_machine_emergency_restart,
496 .restart = native_machine_restart,
497 .halt = native_machine_halt,
499 .crash_shutdown = native_machine_crash_shutdown,
503 void machine_power_off(void)
505 machine_ops.power_off();
508 void machine_shutdown(void)
510 machine_ops.shutdown();
513 void machine_emergency_restart(void)
515 machine_ops.emergency_restart();
518 void machine_restart(char *cmd)
520 machine_ops.restart(cmd);
523 void machine_halt(void)
529 void machine_crash_shutdown(struct pt_regs *regs)
531 machine_ops.crash_shutdown(regs);