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>
28 * Power off function, if any
30 void (*pm_power_off)(void);
31 EXPORT_SYMBOL(pm_power_off);
33 static const struct desc_ptr no_idt = {};
34 static int reboot_mode;
35 enum reboot_type reboot_type = BOOT_KBD;
38 #if defined(CONFIG_X86_32) && defined(CONFIG_SMP)
39 static int reboot_cpu = -1;
42 /* reboot=b[ios] | s[mp] | t[riple] | k[bd] | e[fi] [, [w]arm | [c]old]
43 warm Don't set the cold reboot flag
44 cold Set the cold reboot flag
45 bios Reboot by jumping through the BIOS (only for X86_32)
46 smp Reboot by executing reset on BSP or other CPU (only for X86_32)
47 triple Force a triple fault (init)
48 kbd Use the keyboard controller. cold reset (default)
49 acpi Use the RESET_REG in the FADT
50 efi Use efi reset_system runtime service
51 force Avoid anything that could hang.
53 static int __init reboot_setup(char *str)
68 if (isdigit(*(str+1))) {
69 reboot_cpu = (int) (*(str+1) - '0');
70 if (isdigit(*(str+2)))
71 reboot_cpu = reboot_cpu*10 + (int)(*(str+2) - '0');
73 /* we will leave sorting out the final value
74 when we are ready to reboot, since we might not
75 have set up boot_cpu_id or smp_num_cpu */
77 #endif /* CONFIG_SMP */
93 str = strchr(str, ',');
102 __setup("reboot=", reboot_setup);
107 * Reboot options and system auto-detection code provided by
108 * Dell Inc. so their systems "just work". :-)
112 * Some machines require the "reboot=b" commandline option,
113 * this quirk makes that automatic.
115 static int __init set_bios_reboot(const struct dmi_system_id *d)
117 if (reboot_type != BOOT_BIOS) {
118 reboot_type = BOOT_BIOS;
119 printk(KERN_INFO "%s series board detected. Selecting BIOS-method for reboots.\n", d->ident);
124 static struct dmi_system_id __initdata reboot_dmi_table[] = {
125 { /* Handle problems with rebooting on Dell E520's */
126 .callback = set_bios_reboot,
127 .ident = "Dell E520",
129 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
130 DMI_MATCH(DMI_PRODUCT_NAME, "Dell DM061"),
133 { /* Handle problems with rebooting on Dell 1300's */
134 .callback = set_bios_reboot,
135 .ident = "Dell PowerEdge 1300",
137 DMI_MATCH(DMI_SYS_VENDOR, "Dell Computer Corporation"),
138 DMI_MATCH(DMI_PRODUCT_NAME, "PowerEdge 1300/"),
141 { /* Handle problems with rebooting on Dell 300's */
142 .callback = set_bios_reboot,
143 .ident = "Dell PowerEdge 300",
145 DMI_MATCH(DMI_SYS_VENDOR, "Dell Computer Corporation"),
146 DMI_MATCH(DMI_PRODUCT_NAME, "PowerEdge 300/"),
149 { /* Handle problems with rebooting on Dell Optiplex 745's SFF*/
150 .callback = set_bios_reboot,
151 .ident = "Dell OptiPlex 745",
153 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
154 DMI_MATCH(DMI_PRODUCT_NAME, "OptiPlex 745"),
157 { /* Handle problems with rebooting on Dell Optiplex 745's DFF*/
158 .callback = set_bios_reboot,
159 .ident = "Dell OptiPlex 745",
161 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
162 DMI_MATCH(DMI_PRODUCT_NAME, "OptiPlex 745"),
163 DMI_MATCH(DMI_BOARD_NAME, "0MM599"),
166 { /* Handle problems with rebooting on Dell Optiplex 745 with 0KW626 */
167 .callback = set_bios_reboot,
168 .ident = "Dell OptiPlex 745",
170 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
171 DMI_MATCH(DMI_PRODUCT_NAME, "OptiPlex 745"),
172 DMI_MATCH(DMI_BOARD_NAME, "0KW626"),
175 { /* Handle problems with rebooting on Dell 2400's */
176 .callback = set_bios_reboot,
177 .ident = "Dell PowerEdge 2400",
179 DMI_MATCH(DMI_SYS_VENDOR, "Dell Computer Corporation"),
180 DMI_MATCH(DMI_PRODUCT_NAME, "PowerEdge 2400"),
183 { /* Handle problems with rebooting on Dell T5400's */
184 .callback = set_bios_reboot,
185 .ident = "Dell Precision T5400",
187 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
188 DMI_MATCH(DMI_PRODUCT_NAME, "Precision WorkStation T5400"),
191 { /* Handle problems with rebooting on HP laptops */
192 .callback = set_bios_reboot,
193 .ident = "HP Compaq Laptop",
195 DMI_MATCH(DMI_SYS_VENDOR, "Hewlett-Packard"),
196 DMI_MATCH(DMI_PRODUCT_NAME, "HP Compaq"),
202 static int __init reboot_init(void)
204 dmi_check_system(reboot_dmi_table);
207 core_initcall(reboot_init);
209 /* The following code and data reboots the machine by switching to real
210 mode and jumping to the BIOS reset entry point, as if the CPU has
211 really been reset. The previous version asked the keyboard
212 controller to pulse the CPU reset line, which is more thorough, but
213 doesn't work with at least one type of 486 motherboard. It is easy
214 to stop this code working; hence the copious comments. */
215 static const unsigned long long
216 real_mode_gdt_entries [3] =
218 0x0000000000000000ULL, /* Null descriptor */
219 0x00009b000000ffffULL, /* 16-bit real-mode 64k code at 0x00000000 */
220 0x000093000100ffffULL /* 16-bit real-mode 64k data at 0x00000100 */
223 static const struct desc_ptr
224 real_mode_gdt = { sizeof (real_mode_gdt_entries) - 1, (long)real_mode_gdt_entries },
225 real_mode_idt = { 0x3ff, 0 };
227 /* This is 16-bit protected mode code to disable paging and the cache,
228 switch to real mode and jump to the BIOS reset code.
230 The instruction that switches to real mode by writing to CR0 must be
231 followed immediately by a far jump instruction, which set CS to a
232 valid value for real mode, and flushes the prefetch queue to avoid
233 running instructions that have already been decoded in protected
236 Clears all the flags except ET, especially PG (paging), PE
237 (protected-mode enable) and TS (task switch for coprocessor state
238 save). Flushes the TLB after paging has been disabled. Sets CD and
239 NW, to disable the cache on a 486, and invalidates the cache. This
240 is more like the state of a 486 after reset. I don't know if
241 something else should be done for other chips.
243 More could be done here to set up the registers as if a CPU reset had
244 occurred; hopefully real BIOSs don't assume much. */
245 static const unsigned char real_mode_switch [] =
247 0x66, 0x0f, 0x20, 0xc0, /* movl %cr0,%eax */
248 0x66, 0x83, 0xe0, 0x11, /* andl $0x00000011,%eax */
249 0x66, 0x0d, 0x00, 0x00, 0x00, 0x60, /* orl $0x60000000,%eax */
250 0x66, 0x0f, 0x22, 0xc0, /* movl %eax,%cr0 */
251 0x66, 0x0f, 0x22, 0xd8, /* movl %eax,%cr3 */
252 0x66, 0x0f, 0x20, 0xc3, /* movl %cr0,%ebx */
253 0x66, 0x81, 0xe3, 0x00, 0x00, 0x00, 0x60, /* andl $0x60000000,%ebx */
254 0x74, 0x02, /* jz f */
255 0x0f, 0x09, /* wbinvd */
256 0x24, 0x10, /* f: andb $0x10,al */
257 0x66, 0x0f, 0x22, 0xc0 /* movl %eax,%cr0 */
259 static const unsigned char jump_to_bios [] =
261 0xea, 0x00, 0x00, 0xff, 0xff /* ljmp $0xffff,$0x0000 */
265 * Switch to real mode and then execute the code
266 * specified by the code and length parameters.
267 * We assume that length will aways be less that 100!
269 void machine_real_restart(const unsigned char *code, int length)
273 /* Write zero to CMOS register number 0x0f, which the BIOS POST
274 routine will recognize as telling it to do a proper reboot. (Well
275 that's what this book in front of me says -- it may only apply to
276 the Phoenix BIOS though, it's not clear). At the same time,
277 disable NMIs by setting the top bit in the CMOS address register,
278 as we're about to do peculiar things to the CPU. I'm not sure if
279 `outb_p' is needed instead of just `outb'. Use it to be on the
280 safe side. (Yes, CMOS_WRITE does outb_p's. - Paul G.)
282 spin_lock(&rtc_lock);
283 CMOS_WRITE(0x00, 0x8f);
284 spin_unlock(&rtc_lock);
286 /* Remap the kernel at virtual address zero, as well as offset zero
287 from the kernel segment. This assumes the kernel segment starts at
288 virtual address PAGE_OFFSET. */
289 memcpy(swapper_pg_dir, swapper_pg_dir + KERNEL_PGD_BOUNDARY,
290 sizeof(swapper_pg_dir [0]) * KERNEL_PGD_PTRS);
293 * Use `swapper_pg_dir' as our page directory.
295 load_cr3(swapper_pg_dir);
297 /* Write 0x1234 to absolute memory location 0x472. The BIOS reads
298 this on booting to tell it to "Bypass memory test (also warm
299 boot)". This seems like a fairly standard thing that gets set by
300 REBOOT.COM programs, and the previous reset routine did this
302 *((unsigned short *)0x472) = reboot_mode;
304 /* For the switch to real mode, copy some code to low memory. It has
305 to be in the first 64k because it is running in 16-bit mode, and it
306 has to have the same physical and virtual address, because it turns
307 off paging. Copy it near the end of the first page, out of the way
308 of BIOS variables. */
309 memcpy((void *)(0x1000 - sizeof(real_mode_switch) - 100),
310 real_mode_switch, sizeof (real_mode_switch));
311 memcpy((void *)(0x1000 - 100), code, length);
313 /* Set up the IDT for real mode. */
314 load_idt(&real_mode_idt);
316 /* Set up a GDT from which we can load segment descriptors for real
317 mode. The GDT is not used in real mode; it is just needed here to
318 prepare the descriptors. */
319 load_gdt(&real_mode_gdt);
321 /* Load the data segment registers, and thus the descriptors ready for
322 real mode. The base address of each segment is 0x100, 16 times the
323 selector value being loaded here. This is so that the segment
324 registers don't have to be reloaded after switching to real mode:
325 the values are consistent for real mode operation already. */
326 __asm__ __volatile__ ("movl $0x0010,%%eax\n"
327 "\tmovl %%eax,%%ds\n"
328 "\tmovl %%eax,%%es\n"
329 "\tmovl %%eax,%%fs\n"
330 "\tmovl %%eax,%%gs\n"
331 "\tmovl %%eax,%%ss" : : : "eax");
333 /* Jump to the 16-bit code that we copied earlier. It disables paging
334 and the cache, switches to real mode, and jumps to the BIOS reset
336 __asm__ __volatile__ ("ljmp $0x0008,%0"
338 : "i" ((void *)(0x1000 - sizeof (real_mode_switch) - 100)));
340 #ifdef CONFIG_APM_MODULE
341 EXPORT_SYMBOL(machine_real_restart);
344 #endif /* CONFIG_X86_32 */
346 static inline void kb_wait(void)
350 for (i = 0; i < 0x10000; i++) {
351 if ((inb(0x64) & 0x02) == 0)
357 void __attribute__((weak)) mach_reboot_fixups(void)
361 static void native_machine_emergency_restart(void)
365 /* Tell the BIOS if we want cold or warm reboot */
366 *((unsigned short *)__va(0x472)) = reboot_mode;
369 /* Could also try the reset bit in the Hammer NB */
370 switch (reboot_type) {
372 mach_reboot_fixups(); /* for board specific fixups */
374 for (i = 0; i < 10; i++) {
377 outb(0xfe, 0x64); /* pulse reset low */
383 __asm__ __volatile__("int3");
385 reboot_type = BOOT_KBD;
390 machine_real_restart(jump_to_bios, sizeof(jump_to_bios));
392 reboot_type = BOOT_KBD;
398 reboot_type = BOOT_KBD;
404 efi.reset_system(reboot_mode ? EFI_RESET_WARM : EFI_RESET_COLD,
405 EFI_SUCCESS, 0, NULL);
407 reboot_type = BOOT_KBD;
413 void native_machine_shutdown(void)
415 /* Stop the cpus and apics */
418 /* The boot cpu is always logical cpu 0 */
419 int reboot_cpu_id = 0;
422 /* See if there has been given a command line override */
423 if ((reboot_cpu != -1) && (reboot_cpu < NR_CPUS) &&
424 cpu_online(reboot_cpu))
425 reboot_cpu_id = reboot_cpu;
428 /* Make certain the cpu I'm about to reboot on is online */
429 if (!cpu_online(reboot_cpu_id))
430 reboot_cpu_id = smp_processor_id();
432 /* Make certain I only run on the appropriate processor */
433 set_cpus_allowed_ptr(current, &cpumask_of_cpu(reboot_cpu_id));
435 /* O.K Now that I'm on the appropriate processor,
436 * stop all of the others.
443 #ifdef CONFIG_X86_IO_APIC
447 #ifdef CONFIG_HPET_TIMER
452 pci_iommu_shutdown();
456 static void native_machine_restart(char *__unused)
458 printk("machine restart\n");
462 machine_emergency_restart();
465 static void native_machine_halt(void)
469 static void native_machine_power_off(void)
478 struct machine_ops machine_ops = {
479 .power_off = native_machine_power_off,
480 .shutdown = native_machine_shutdown,
481 .emergency_restart = native_machine_emergency_restart,
482 .restart = native_machine_restart,
483 .halt = native_machine_halt,
485 .crash_shutdown = native_machine_crash_shutdown,
489 void machine_power_off(void)
491 machine_ops.power_off();
494 void machine_shutdown(void)
496 machine_ops.shutdown();
499 void machine_emergency_restart(void)
501 machine_ops.emergency_restart();
504 void machine_restart(char *cmd)
506 machine_ops.restart(cmd);
509 void machine_halt(void)
515 void machine_crash_shutdown(struct pt_regs *regs)
517 machine_ops.crash_shutdown(regs);
522 #if defined(CONFIG_SMP)
524 /* This keeps a track of which one is crashing cpu. */
525 static int crashing_cpu;
526 static nmi_shootdown_cb shootdown_callback;
528 static atomic_t waiting_for_crash_ipi;
530 static int crash_nmi_callback(struct notifier_block *self,
531 unsigned long val, void *data)
535 if (val != DIE_NMI_IPI)
538 cpu = raw_smp_processor_id();
540 /* Don't do anything if this handler is invoked on crashing cpu.
541 * Otherwise, system will completely hang. Crashing cpu can get
542 * an NMI if system was initially booted with nmi_watchdog parameter.
544 if (cpu == crashing_cpu)
548 shootdown_callback(cpu, (struct die_args *)data);
550 atomic_dec(&waiting_for_crash_ipi);
551 /* Assume hlt works */
559 static void smp_send_nmi_allbutself(void)
561 cpumask_t mask = cpu_online_map;
562 cpu_clear(safe_smp_processor_id(), mask);
563 if (!cpus_empty(mask))
564 send_IPI_mask(mask, NMI_VECTOR);
567 static struct notifier_block crash_nmi_nb = {
568 .notifier_call = crash_nmi_callback,
571 /* Halt all other CPUs, calling the specified function on each of them
573 * This function can be used to halt all other CPUs on crash
574 * or emergency reboot time. The function passed as parameter
575 * will be called inside a NMI handler on all CPUs.
577 void nmi_shootdown_cpus(nmi_shootdown_cb callback)
582 /* Make a note of crashing cpu. Will be used in NMI callback.*/
583 crashing_cpu = safe_smp_processor_id();
585 shootdown_callback = callback;
587 atomic_set(&waiting_for_crash_ipi, num_online_cpus() - 1);
588 /* Would it be better to replace the trap vector here? */
589 if (register_die_notifier(&crash_nmi_nb))
590 return; /* return what? */
591 /* Ensure the new callback function is set before sending
596 smp_send_nmi_allbutself();
598 msecs = 1000; /* Wait at most a second for the other cpus to stop */
599 while ((atomic_read(&waiting_for_crash_ipi) > 0) && msecs) {
604 /* Leave the nmi callback set */
606 #else /* !CONFIG_SMP */
607 void nmi_shootdown_cpus(nmi_shootdown_cb callback)
609 /* No other CPUs to shoot down */