1 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
2
3 #include <linux/module.h>
4 #include <linux/reboot.h>
5 #include <linux/init.h>
6 #include <linux/pm.h>
7 #include <linux/efi.h>
8 #include <linux/dmi.h>
9 #include <linux/sched.h>
10 #include <linux/tboot.h>
11 #include <linux/delay.h>
12 #include <acpi/reboot.h>
13 #include <asm/io.h>
14 #include <asm/apic.h>
15 #include <asm/io_apic.h>
16 #include <asm/desc.h>
17 #include <asm/hpet.h>
18 #include <asm/pgtable.h>
19 #include <asm/proto.h>
20 #include <asm/reboot_fixups.h>
21 #include <asm/reboot.h>
22 #include <asm/pci_x86.h>
23 #include <asm/virtext.h>
24 #include <asm/cpu.h>
25 #include <asm/nmi.h>
26 #include <asm/smp.h>
27
28 #include <linux/ctype.h>
29 #include <linux/mc146818rtc.h>
30 #include <asm/realmode.h>
31 #include <asm/x86_init.h>
32 #include <asm/efi.h>
33
34 /*
35 * Power off function, if any
36 */
37 void (*pm_power_off)(void);
38 EXPORT_SYMBOL(pm_power_off);
39
40 static const struct desc_ptr no_idt = {};
41
42 /*
43 * This is set if we need to go through the 'emergency' path.
44 * When machine_emergency_restart() is called, we may be on
45 * an inconsistent state and won't be able to do a clean cleanup
46 */
47 static int reboot_emergency;
48
49 /* This is set by the PCI code if either type 1 or type 2 PCI is detected */
50 bool port_cf9_safe = false;
51
52 /*
53 * Reboot options and system auto-detection code provided by
54 * Dell Inc. so their systems "just work". :-)
55 */
56
57 /*
58 * Some machines require the "reboot=b" or "reboot=k" commandline options,
59 * this quirk makes that automatic.
60 */
set_bios_reboot(const struct dmi_system_id * d)61 static int __init set_bios_reboot(const struct dmi_system_id *d)
62 {
63 if (reboot_type != BOOT_BIOS) {
64 reboot_type = BOOT_BIOS;
65 pr_info("%s series board detected. Selecting %s-method for reboots.\n",
66 d->ident, "BIOS");
67 }
68 return 0;
69 }
70
machine_real_restart(unsigned int type)71 void __noreturn machine_real_restart(unsigned int type)
72 {
73 local_irq_disable();
74
75 /*
76 * Write zero to CMOS register number 0x0f, which the BIOS POST
77 * routine will recognize as telling it to do a proper reboot. (Well
78 * that's what this book in front of me says -- it may only apply to
79 * the Phoenix BIOS though, it's not clear). At the same time,
80 * disable NMIs by setting the top bit in the CMOS address register,
81 * as we're about to do peculiar things to the CPU. I'm not sure if
82 * `outb_p' is needed instead of just `outb'. Use it to be on the
83 * safe side. (Yes, CMOS_WRITE does outb_p's. - Paul G.)
84 */
85 spin_lock(&rtc_lock);
86 CMOS_WRITE(0x00, 0x8f);
87 spin_unlock(&rtc_lock);
88
89 /*
90 * Switch back to the initial page table.
91 */
92 #ifdef CONFIG_X86_32
93 load_cr3(initial_page_table);
94 #else
95 write_cr3(real_mode_header->trampoline_pgd);
96
97 /* Exiting long mode will fail if CR4.PCIDE is set. */
98 if (static_cpu_has(X86_FEATURE_PCID))
99 cr4_clear_bits(X86_CR4_PCIDE);
100 #endif
101
102 /* Jump to the identity-mapped low memory code */
103 #ifdef CONFIG_X86_32
104 asm volatile("jmpl *%0" : :
105 "rm" (real_mode_header->machine_real_restart_asm),
106 "a" (type));
107 #else
108 asm volatile("ljmpl *%0" : :
109 "m" (real_mode_header->machine_real_restart_asm),
110 "D" (type));
111 #endif
112 unreachable();
113 }
114 #ifdef CONFIG_APM_MODULE
115 EXPORT_SYMBOL(machine_real_restart);
116 #endif
117
118 /*
119 * Some Apple MacBook and MacBookPro's needs reboot=p to be able to reboot
120 */
set_pci_reboot(const struct dmi_system_id * d)121 static int __init set_pci_reboot(const struct dmi_system_id *d)
122 {
123 if (reboot_type != BOOT_CF9_FORCE) {
124 reboot_type = BOOT_CF9_FORCE;
125 pr_info("%s series board detected. Selecting %s-method for reboots.\n",
126 d->ident, "PCI");
127 }
128 return 0;
129 }
130
set_kbd_reboot(const struct dmi_system_id * d)131 static int __init set_kbd_reboot(const struct dmi_system_id *d)
132 {
133 if (reboot_type != BOOT_KBD) {
134 reboot_type = BOOT_KBD;
135 pr_info("%s series board detected. Selecting %s-method for reboot.\n",
136 d->ident, "KBD");
137 }
138 return 0;
139 }
140
141 /*
142 * This is a single dmi_table handling all reboot quirks.
143 */
144 static struct dmi_system_id __initdata reboot_dmi_table[] = {
145
146 /* Acer */
147 { /* Handle reboot issue on Acer Aspire one */
148 .callback = set_kbd_reboot,
149 .ident = "Acer Aspire One A110",
150 .matches = {
151 DMI_MATCH(DMI_SYS_VENDOR, "Acer"),
152 DMI_MATCH(DMI_PRODUCT_NAME, "AOA110"),
153 },
154 },
155
156 /* Apple */
157 { /* Handle problems with rebooting on Apple MacBook5 */
158 .callback = set_pci_reboot,
159 .ident = "Apple MacBook5",
160 .matches = {
161 DMI_MATCH(DMI_SYS_VENDOR, "Apple Inc."),
162 DMI_MATCH(DMI_PRODUCT_NAME, "MacBook5"),
163 },
164 },
165 { /* Handle problems with rebooting on Apple MacBook6,1 */
166 .callback = set_pci_reboot,
167 .ident = "Apple MacBook6,1",
168 .matches = {
169 DMI_MATCH(DMI_SYS_VENDOR, "Apple Inc."),
170 DMI_MATCH(DMI_PRODUCT_NAME, "MacBook6,1"),
171 },
172 },
173 { /* Handle problems with rebooting on Apple MacBookPro5 */
174 .callback = set_pci_reboot,
175 .ident = "Apple MacBookPro5",
176 .matches = {
177 DMI_MATCH(DMI_SYS_VENDOR, "Apple Inc."),
178 DMI_MATCH(DMI_PRODUCT_NAME, "MacBookPro5"),
179 },
180 },
181 { /* Handle problems with rebooting on Apple Macmini3,1 */
182 .callback = set_pci_reboot,
183 .ident = "Apple Macmini3,1",
184 .matches = {
185 DMI_MATCH(DMI_SYS_VENDOR, "Apple Inc."),
186 DMI_MATCH(DMI_PRODUCT_NAME, "Macmini3,1"),
187 },
188 },
189 { /* Handle problems with rebooting on the iMac9,1. */
190 .callback = set_pci_reboot,
191 .ident = "Apple iMac9,1",
192 .matches = {
193 DMI_MATCH(DMI_SYS_VENDOR, "Apple Inc."),
194 DMI_MATCH(DMI_PRODUCT_NAME, "iMac9,1"),
195 },
196 },
197 { /* Handle problems with rebooting on the iMac10,1. */
198 .callback = set_pci_reboot,
199 .ident = "Apple iMac10,1",
200 .matches = {
201 DMI_MATCH(DMI_SYS_VENDOR, "Apple Inc."),
202 DMI_MATCH(DMI_PRODUCT_NAME, "iMac10,1"),
203 },
204 },
205
206 /* ASRock */
207 { /* Handle problems with rebooting on ASRock Q1900DC-ITX */
208 .callback = set_pci_reboot,
209 .ident = "ASRock Q1900DC-ITX",
210 .matches = {
211 DMI_MATCH(DMI_BOARD_VENDOR, "ASRock"),
212 DMI_MATCH(DMI_BOARD_NAME, "Q1900DC-ITX"),
213 },
214 },
215
216 /* ASUS */
217 { /* Handle problems with rebooting on ASUS P4S800 */
218 .callback = set_bios_reboot,
219 .ident = "ASUS P4S800",
220 .matches = {
221 DMI_MATCH(DMI_BOARD_VENDOR, "ASUSTeK Computer INC."),
222 DMI_MATCH(DMI_BOARD_NAME, "P4S800"),
223 },
224 },
225
226 /* Certec */
227 { /* Handle problems with rebooting on Certec BPC600 */
228 .callback = set_pci_reboot,
229 .ident = "Certec BPC600",
230 .matches = {
231 DMI_MATCH(DMI_SYS_VENDOR, "Certec"),
232 DMI_MATCH(DMI_PRODUCT_NAME, "BPC600"),
233 },
234 },
235
236 /* Dell */
237 { /* Handle problems with rebooting on Dell DXP061 */
238 .callback = set_bios_reboot,
239 .ident = "Dell DXP061",
240 .matches = {
241 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
242 DMI_MATCH(DMI_PRODUCT_NAME, "Dell DXP061"),
243 },
244 },
245 { /* Handle problems with rebooting on Dell E520's */
246 .callback = set_bios_reboot,
247 .ident = "Dell E520",
248 .matches = {
249 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
250 DMI_MATCH(DMI_PRODUCT_NAME, "Dell DM061"),
251 },
252 },
253 { /* Handle problems with rebooting on the Latitude E5410. */
254 .callback = set_pci_reboot,
255 .ident = "Dell Latitude E5410",
256 .matches = {
257 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
258 DMI_MATCH(DMI_PRODUCT_NAME, "Latitude E5410"),
259 },
260 },
261 { /* Handle problems with rebooting on the Latitude E5420. */
262 .callback = set_pci_reboot,
263 .ident = "Dell Latitude E5420",
264 .matches = {
265 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
266 DMI_MATCH(DMI_PRODUCT_NAME, "Latitude E5420"),
267 },
268 },
269 { /* Handle problems with rebooting on the Latitude E6320. */
270 .callback = set_pci_reboot,
271 .ident = "Dell Latitude E6320",
272 .matches = {
273 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
274 DMI_MATCH(DMI_PRODUCT_NAME, "Latitude E6320"),
275 },
276 },
277 { /* Handle problems with rebooting on the Latitude E6420. */
278 .callback = set_pci_reboot,
279 .ident = "Dell Latitude E6420",
280 .matches = {
281 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
282 DMI_MATCH(DMI_PRODUCT_NAME, "Latitude E6420"),
283 },
284 },
285 { /* Handle problems with rebooting on Dell Optiplex 330 with 0KP561 */
286 .callback = set_bios_reboot,
287 .ident = "Dell OptiPlex 330",
288 .matches = {
289 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
290 DMI_MATCH(DMI_PRODUCT_NAME, "OptiPlex 330"),
291 DMI_MATCH(DMI_BOARD_NAME, "0KP561"),
292 },
293 },
294 { /* Handle problems with rebooting on Dell Optiplex 360 with 0T656F */
295 .callback = set_bios_reboot,
296 .ident = "Dell OptiPlex 360",
297 .matches = {
298 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
299 DMI_MATCH(DMI_PRODUCT_NAME, "OptiPlex 360"),
300 DMI_MATCH(DMI_BOARD_NAME, "0T656F"),
301 },
302 },
303 { /* Handle problems with rebooting on Dell Optiplex 745's SFF */
304 .callback = set_bios_reboot,
305 .ident = "Dell OptiPlex 745",
306 .matches = {
307 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
308 DMI_MATCH(DMI_PRODUCT_NAME, "OptiPlex 745"),
309 },
310 },
311 { /* Handle problems with rebooting on Dell Optiplex 745's DFF */
312 .callback = set_bios_reboot,
313 .ident = "Dell OptiPlex 745",
314 .matches = {
315 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
316 DMI_MATCH(DMI_PRODUCT_NAME, "OptiPlex 745"),
317 DMI_MATCH(DMI_BOARD_NAME, "0MM599"),
318 },
319 },
320 { /* Handle problems with rebooting on Dell Optiplex 745 with 0KW626 */
321 .callback = set_bios_reboot,
322 .ident = "Dell OptiPlex 745",
323 .matches = {
324 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
325 DMI_MATCH(DMI_PRODUCT_NAME, "OptiPlex 745"),
326 DMI_MATCH(DMI_BOARD_NAME, "0KW626"),
327 },
328 },
329 { /* Handle problems with rebooting on Dell OptiPlex 760 with 0G919G */
330 .callback = set_bios_reboot,
331 .ident = "Dell OptiPlex 760",
332 .matches = {
333 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
334 DMI_MATCH(DMI_PRODUCT_NAME, "OptiPlex 760"),
335 DMI_MATCH(DMI_BOARD_NAME, "0G919G"),
336 },
337 },
338 { /* Handle problems with rebooting on the OptiPlex 990. */
339 .callback = set_pci_reboot,
340 .ident = "Dell OptiPlex 990 BIOS A0x",
341 .matches = {
342 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
343 DMI_MATCH(DMI_PRODUCT_NAME, "OptiPlex 990"),
344 DMI_MATCH(DMI_BIOS_VERSION, "A0"),
345 },
346 },
347 { /* Handle problems with rebooting on Dell 300's */
348 .callback = set_bios_reboot,
349 .ident = "Dell PowerEdge 300",
350 .matches = {
351 DMI_MATCH(DMI_SYS_VENDOR, "Dell Computer Corporation"),
352 DMI_MATCH(DMI_PRODUCT_NAME, "PowerEdge 300/"),
353 },
354 },
355 { /* Handle problems with rebooting on Dell 1300's */
356 .callback = set_bios_reboot,
357 .ident = "Dell PowerEdge 1300",
358 .matches = {
359 DMI_MATCH(DMI_SYS_VENDOR, "Dell Computer Corporation"),
360 DMI_MATCH(DMI_PRODUCT_NAME, "PowerEdge 1300/"),
361 },
362 },
363 { /* Handle problems with rebooting on Dell 2400's */
364 .callback = set_bios_reboot,
365 .ident = "Dell PowerEdge 2400",
366 .matches = {
367 DMI_MATCH(DMI_SYS_VENDOR, "Dell Computer Corporation"),
368 DMI_MATCH(DMI_PRODUCT_NAME, "PowerEdge 2400"),
369 },
370 },
371 { /* Handle problems with rebooting on the Dell PowerEdge C6100. */
372 .callback = set_pci_reboot,
373 .ident = "Dell PowerEdge C6100",
374 .matches = {
375 DMI_MATCH(DMI_SYS_VENDOR, "Dell"),
376 DMI_MATCH(DMI_PRODUCT_NAME, "C6100"),
377 },
378 },
379 { /* Handle problems with rebooting on the Precision M6600. */
380 .callback = set_pci_reboot,
381 .ident = "Dell Precision M6600",
382 .matches = {
383 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
384 DMI_MATCH(DMI_PRODUCT_NAME, "Precision M6600"),
385 },
386 },
387 { /* Handle problems with rebooting on Dell T5400's */
388 .callback = set_bios_reboot,
389 .ident = "Dell Precision T5400",
390 .matches = {
391 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
392 DMI_MATCH(DMI_PRODUCT_NAME, "Precision WorkStation T5400"),
393 },
394 },
395 { /* Handle problems with rebooting on Dell T7400's */
396 .callback = set_bios_reboot,
397 .ident = "Dell Precision T7400",
398 .matches = {
399 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
400 DMI_MATCH(DMI_PRODUCT_NAME, "Precision WorkStation T7400"),
401 },
402 },
403 { /* Handle problems with rebooting on Dell XPS710 */
404 .callback = set_bios_reboot,
405 .ident = "Dell XPS710",
406 .matches = {
407 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
408 DMI_MATCH(DMI_PRODUCT_NAME, "Dell XPS710"),
409 },
410 },
411
412 /* Hewlett-Packard */
413 { /* Handle problems with rebooting on HP laptops */
414 .callback = set_bios_reboot,
415 .ident = "HP Compaq Laptop",
416 .matches = {
417 DMI_MATCH(DMI_SYS_VENDOR, "Hewlett-Packard"),
418 DMI_MATCH(DMI_PRODUCT_NAME, "HP Compaq"),
419 },
420 },
421
422 { /* PCIe Wifi card isn't detected after reboot otherwise */
423 .callback = set_pci_reboot,
424 .ident = "Zotac ZBOX CI327 nano",
425 .matches = {
426 DMI_MATCH(DMI_SYS_VENDOR, "NA"),
427 DMI_MATCH(DMI_PRODUCT_NAME, "ZBOX-CI327NANO-GS-01"),
428 },
429 },
430
431 /* Sony */
432 { /* Handle problems with rebooting on Sony VGN-Z540N */
433 .callback = set_bios_reboot,
434 .ident = "Sony VGN-Z540N",
435 .matches = {
436 DMI_MATCH(DMI_SYS_VENDOR, "Sony Corporation"),
437 DMI_MATCH(DMI_PRODUCT_NAME, "VGN-Z540N"),
438 },
439 },
440
441 { }
442 };
443
reboot_init(void)444 static int __init reboot_init(void)
445 {
446 int rv;
447
448 /*
449 * Only do the DMI check if reboot_type hasn't been overridden
450 * on the command line
451 */
452 if (!reboot_default)
453 return 0;
454
455 /*
456 * The DMI quirks table takes precedence. If no quirks entry
457 * matches and the ACPI Hardware Reduced bit is set, force EFI
458 * reboot.
459 */
460 rv = dmi_check_system(reboot_dmi_table);
461
462 if (!rv && efi_reboot_required())
463 reboot_type = BOOT_EFI;
464
465 return 0;
466 }
467 core_initcall(reboot_init);
468
kb_wait(void)469 static inline void kb_wait(void)
470 {
471 int i;
472
473 for (i = 0; i < 0x10000; i++) {
474 if ((inb(0x64) & 0x02) == 0)
475 break;
476 udelay(2);
477 }
478 }
479
vmxoff_nmi(int cpu,struct pt_regs * regs)480 static void vmxoff_nmi(int cpu, struct pt_regs *regs)
481 {
482 cpu_emergency_vmxoff();
483 }
484
485 /* Use NMIs as IPIs to tell all CPUs to disable virtualization */
emergency_vmx_disable_all(void)486 static void emergency_vmx_disable_all(void)
487 {
488 /* Just make sure we won't change CPUs while doing this */
489 local_irq_disable();
490
491 /*
492 * Disable VMX on all CPUs before rebooting, otherwise we risk hanging
493 * the machine, because the CPU blocks INIT when it's in VMX root.
494 *
495 * We can't take any locks and we may be on an inconsistent state, so
496 * use NMIs as IPIs to tell the other CPUs to exit VMX root and halt.
497 *
498 * Do the NMI shootdown even if VMX if off on _this_ CPU, as that
499 * doesn't prevent a different CPU from being in VMX root operation.
500 */
501 if (cpu_has_vmx()) {
502 /* Safely force _this_ CPU out of VMX root operation. */
503 __cpu_emergency_vmxoff();
504
505 /* Halt and exit VMX root operation on the other CPUs. */
506 nmi_shootdown_cpus(vmxoff_nmi);
507
508 }
509 }
510
511
mach_reboot_fixups(void)512 void __attribute__((weak)) mach_reboot_fixups(void)
513 {
514 }
515
516 /*
517 * To the best of our knowledge Windows compatible x86 hardware expects
518 * the following on reboot:
519 *
520 * 1) If the FADT has the ACPI reboot register flag set, try it
521 * 2) If still alive, write to the keyboard controller
522 * 3) If still alive, write to the ACPI reboot register again
523 * 4) If still alive, write to the keyboard controller again
524 * 5) If still alive, call the EFI runtime service to reboot
525 * 6) If no EFI runtime service, call the BIOS to do a reboot
526 *
527 * We default to following the same pattern. We also have
528 * two other reboot methods: 'triple fault' and 'PCI', which
529 * can be triggered via the reboot= kernel boot option or
530 * via quirks.
531 *
532 * This means that this function can never return, it can misbehave
533 * by not rebooting properly and hanging.
534 */
native_machine_emergency_restart(void)535 static void native_machine_emergency_restart(void)
536 {
537 int i;
538 int attempt = 0;
539 int orig_reboot_type = reboot_type;
540 unsigned short mode;
541
542 if (reboot_emergency)
543 emergency_vmx_disable_all();
544
545 tboot_shutdown(TB_SHUTDOWN_REBOOT);
546
547 /* Tell the BIOS if we want cold or warm reboot */
548 mode = reboot_mode == REBOOT_WARM ? 0x1234 : 0;
549 *((unsigned short *)__va(0x472)) = mode;
550
551 for (;;) {
552 /* Could also try the reset bit in the Hammer NB */
553 switch (reboot_type) {
554 case BOOT_ACPI:
555 acpi_reboot();
556 reboot_type = BOOT_KBD;
557 break;
558
559 case BOOT_KBD:
560 mach_reboot_fixups(); /* For board specific fixups */
561
562 for (i = 0; i < 10; i++) {
563 kb_wait();
564 udelay(50);
565 outb(0xfe, 0x64); /* Pulse reset low */
566 udelay(50);
567 }
568 if (attempt == 0 && orig_reboot_type == BOOT_ACPI) {
569 attempt = 1;
570 reboot_type = BOOT_ACPI;
571 } else {
572 reboot_type = BOOT_EFI;
573 }
574 break;
575
576 case BOOT_EFI:
577 efi_reboot(reboot_mode, NULL);
578 reboot_type = BOOT_BIOS;
579 break;
580
581 case BOOT_BIOS:
582 machine_real_restart(MRR_BIOS);
583
584 /* We're probably dead after this, but... */
585 reboot_type = BOOT_CF9_SAFE;
586 break;
587
588 case BOOT_CF9_FORCE:
589 port_cf9_safe = true;
590 /* Fall through */
591
592 case BOOT_CF9_SAFE:
593 if (port_cf9_safe) {
594 u8 reboot_code = reboot_mode == REBOOT_WARM ? 0x06 : 0x0E;
595 u8 cf9 = inb(0xcf9) & ~reboot_code;
596 outb(cf9|2, 0xcf9); /* Request hard reset */
597 udelay(50);
598 /* Actually do the reset */
599 outb(cf9|reboot_code, 0xcf9);
600 udelay(50);
601 }
602 reboot_type = BOOT_TRIPLE;
603 break;
604
605 case BOOT_TRIPLE:
606 load_idt(&no_idt);
607 __asm__ __volatile__("int3");
608
609 /* We're probably dead after this, but... */
610 reboot_type = BOOT_KBD;
611 break;
612 }
613 }
614 }
615
native_machine_shutdown(void)616 void native_machine_shutdown(void)
617 {
618 /* Stop the cpus and apics */
619 #ifdef CONFIG_X86_IO_APIC
620 /*
621 * Disabling IO APIC before local APIC is a workaround for
622 * erratum AVR31 in "Intel Atom Processor C2000 Product Family
623 * Specification Update". In this situation, interrupts that target
624 * a Logical Processor whose Local APIC is either in the process of
625 * being hardware disabled or software disabled are neither delivered
626 * nor discarded. When this erratum occurs, the processor may hang.
627 *
628 * Even without the erratum, it still makes sense to quiet IO APIC
629 * before disabling Local APIC.
630 */
631 disable_IO_APIC();
632 #endif
633
634 #ifdef CONFIG_SMP
635 /*
636 * Stop all of the others. Also disable the local irq to
637 * not receive the per-cpu timer interrupt which may trigger
638 * scheduler's load balance.
639 */
640 local_irq_disable();
641 stop_other_cpus();
642 #endif
643
644 lapic_shutdown();
645
646 #ifdef CONFIG_HPET_TIMER
647 hpet_disable();
648 #endif
649
650 #ifdef CONFIG_X86_64
651 x86_platform.iommu_shutdown();
652 #endif
653 }
654
__machine_emergency_restart(int emergency)655 static void __machine_emergency_restart(int emergency)
656 {
657 reboot_emergency = emergency;
658 machine_ops.emergency_restart();
659 }
660
native_machine_restart(char * __unused)661 static void native_machine_restart(char *__unused)
662 {
663 pr_notice("machine restart\n");
664
665 if (!reboot_force)
666 machine_shutdown();
667 __machine_emergency_restart(0);
668 }
669
native_machine_halt(void)670 static void native_machine_halt(void)
671 {
672 /* Stop other cpus and apics */
673 machine_shutdown();
674
675 tboot_shutdown(TB_SHUTDOWN_HALT);
676
677 stop_this_cpu(NULL);
678 }
679
native_machine_power_off(void)680 static void native_machine_power_off(void)
681 {
682 if (pm_power_off) {
683 if (!reboot_force)
684 machine_shutdown();
685 pm_power_off();
686 }
687 /* A fallback in case there is no PM info available */
688 tboot_shutdown(TB_SHUTDOWN_HALT);
689 }
690
691 struct machine_ops machine_ops = {
692 .power_off = native_machine_power_off,
693 .shutdown = native_machine_shutdown,
694 .emergency_restart = native_machine_emergency_restart,
695 .restart = native_machine_restart,
696 .halt = native_machine_halt,
697 #ifdef CONFIG_KEXEC_CORE
698 .crash_shutdown = native_machine_crash_shutdown,
699 #endif
700 };
701
machine_power_off(void)702 void machine_power_off(void)
703 {
704 machine_ops.power_off();
705 }
706
machine_shutdown(void)707 void machine_shutdown(void)
708 {
709 machine_ops.shutdown();
710 }
711
machine_emergency_restart(void)712 void machine_emergency_restart(void)
713 {
714 __machine_emergency_restart(1);
715 }
716
machine_restart(char * cmd)717 void machine_restart(char *cmd)
718 {
719 machine_ops.restart(cmd);
720 }
721
machine_halt(void)722 void machine_halt(void)
723 {
724 machine_ops.halt();
725 }
726
727 #ifdef CONFIG_KEXEC_CORE
machine_crash_shutdown(struct pt_regs * regs)728 void machine_crash_shutdown(struct pt_regs *regs)
729 {
730 machine_ops.crash_shutdown(regs);
731 }
732 #endif
733
734
735 #if defined(CONFIG_SMP)
736
737 /* This keeps a track of which one is crashing cpu. */
738 static int crashing_cpu;
739 static nmi_shootdown_cb shootdown_callback;
740
741 static atomic_t waiting_for_crash_ipi;
742
crash_nmi_callback(unsigned int val,struct pt_regs * regs)743 static int crash_nmi_callback(unsigned int val, struct pt_regs *regs)
744 {
745 int cpu;
746
747 cpu = raw_smp_processor_id();
748
749 /*
750 * Don't do anything if this handler is invoked on crashing cpu.
751 * Otherwise, system will completely hang. Crashing cpu can get
752 * an NMI if system was initially booted with nmi_watchdog parameter.
753 */
754 if (cpu == crashing_cpu)
755 return NMI_HANDLED;
756 local_irq_disable();
757
758 shootdown_callback(cpu, regs);
759
760 atomic_dec(&waiting_for_crash_ipi);
761 /* Assume hlt works */
762 halt();
763 for (;;)
764 cpu_relax();
765
766 return NMI_HANDLED;
767 }
768
smp_send_nmi_allbutself(void)769 static void smp_send_nmi_allbutself(void)
770 {
771 apic->send_IPI_allbutself(NMI_VECTOR);
772 }
773
774 /*
775 * Halt all other CPUs, calling the specified function on each of them
776 *
777 * This function can be used to halt all other CPUs on crash
778 * or emergency reboot time. The function passed as parameter
779 * will be called inside a NMI handler on all CPUs.
780 */
nmi_shootdown_cpus(nmi_shootdown_cb callback)781 void nmi_shootdown_cpus(nmi_shootdown_cb callback)
782 {
783 unsigned long msecs;
784 local_irq_disable();
785
786 /* Make a note of crashing cpu. Will be used in NMI callback. */
787 crashing_cpu = safe_smp_processor_id();
788
789 shootdown_callback = callback;
790
791 atomic_set(&waiting_for_crash_ipi, num_online_cpus() - 1);
792 /* Would it be better to replace the trap vector here? */
793 if (register_nmi_handler(NMI_LOCAL, crash_nmi_callback,
794 NMI_FLAG_FIRST, "crash"))
795 return; /* Return what? */
796 /*
797 * Ensure the new callback function is set before sending
798 * out the NMI
799 */
800 wmb();
801
802 smp_send_nmi_allbutself();
803
804 msecs = 1000; /* Wait at most a second for the other cpus to stop */
805 while ((atomic_read(&waiting_for_crash_ipi) > 0) && msecs) {
806 mdelay(1);
807 msecs--;
808 }
809
810 /* Leave the nmi callback set */
811 }
812 #else /* !CONFIG_SMP */
nmi_shootdown_cpus(nmi_shootdown_cb callback)813 void nmi_shootdown_cpus(nmi_shootdown_cb callback)
814 {
815 /* No other CPUs to shoot down */
816 }
817 #endif
818