• Home
  • Line#
  • Scopes#
  • Navigate#
  • Raw
  • Download
1 #include <linux/module.h>
2 #include <linux/reboot.h>
3 #include <linux/init.h>
4 #include <linux/pm.h>
5 #include <linux/efi.h>
6 #include <linux/dmi.h>
7 #include <linux/sched.h>
8 #include <linux/tboot.h>
9 #include <linux/delay.h>
10 #include <acpi/reboot.h>
11 #include <asm/io.h>
12 #include <asm/apic.h>
13 #include <asm/desc.h>
14 #include <asm/hpet.h>
15 #include <asm/pgtable.h>
16 #include <asm/proto.h>
17 #include <asm/reboot_fixups.h>
18 #include <asm/reboot.h>
19 #include <asm/pci_x86.h>
20 #include <asm/virtext.h>
21 #include <asm/cpu.h>
22 #include <asm/nmi.h>
23 
24 #ifdef CONFIG_X86_32
25 # include <linux/ctype.h>
26 # include <linux/mc146818rtc.h>
27 #else
28 # include <asm/x86_init.h>
29 #endif
30 
31 /*
32  * Power off function, if any
33  */
34 void (*pm_power_off)(void);
35 EXPORT_SYMBOL(pm_power_off);
36 
37 static const struct desc_ptr no_idt = {};
38 static int reboot_mode;
39 enum reboot_type reboot_type = BOOT_ACPI;
40 int reboot_force;
41 
42 /* This variable is used privately to keep track of whether or not
43  * reboot_type is still set to its default value (i.e., reboot= hasn't
44  * been set on the command line).  This is needed so that we can
45  * suppress DMI scanning for reboot quirks.  Without it, it's
46  * impossible to override a faulty reboot quirk without recompiling.
47  */
48 static int reboot_default = 1;
49 
50 #if defined(CONFIG_X86_32) && defined(CONFIG_SMP)
51 static int reboot_cpu = -1;
52 #endif
53 
54 /* This is set if we need to go through the 'emergency' path.
55  * When machine_emergency_restart() is called, we may be on
56  * an inconsistent state and won't be able to do a clean cleanup
57  */
58 static int reboot_emergency;
59 
60 /* This is set by the PCI code if either type 1 or type 2 PCI is detected */
61 bool port_cf9_safe = false;
62 
63 /* reboot=b[ios] | s[mp] | t[riple] | k[bd] | e[fi] [, [w]arm | [c]old] | p[ci]
64    warm   Don't set the cold reboot flag
65    cold   Set the cold reboot flag
66    bios   Reboot by jumping through the BIOS (only for X86_32)
67    smp    Reboot by executing reset on BSP or other CPU (only for X86_32)
68    triple Force a triple fault (init)
69    kbd    Use the keyboard controller. cold reset (default)
70    acpi   Use the RESET_REG in the FADT
71    efi    Use efi reset_system runtime service
72    pci    Use the so-called "PCI reset register", CF9
73    force  Avoid anything that could hang.
74  */
reboot_setup(char * str)75 static int __init reboot_setup(char *str)
76 {
77 	for (;;) {
78 		/* Having anything passed on the command line via
79 		 * reboot= will cause us to disable DMI checking
80 		 * below.
81 		 */
82 		reboot_default = 0;
83 
84 		switch (*str) {
85 		case 'w':
86 			reboot_mode = 0x1234;
87 			break;
88 
89 		case 'c':
90 			reboot_mode = 0;
91 			break;
92 
93 #ifdef CONFIG_X86_32
94 #ifdef CONFIG_SMP
95 		case 's':
96 			if (isdigit(*(str+1))) {
97 				reboot_cpu = (int) (*(str+1) - '0');
98 				if (isdigit(*(str+2)))
99 					reboot_cpu = reboot_cpu*10 + (int)(*(str+2) - '0');
100 			}
101 				/* we will leave sorting out the final value
102 				   when we are ready to reboot, since we might not
103 				   have detected BSP APIC ID or smp_num_cpu */
104 			break;
105 #endif /* CONFIG_SMP */
106 
107 		case 'b':
108 #endif
109 		case 'a':
110 		case 'k':
111 		case 't':
112 		case 'e':
113 		case 'p':
114 			reboot_type = *str;
115 			break;
116 
117 		case 'f':
118 			reboot_force = 1;
119 			break;
120 		}
121 
122 		str = strchr(str, ',');
123 		if (str)
124 			str++;
125 		else
126 			break;
127 	}
128 	return 1;
129 }
130 
131 __setup("reboot=", reboot_setup);
132 
133 
134 #ifdef CONFIG_X86_32
135 /*
136  * Reboot options and system auto-detection code provided by
137  * Dell Inc. so their systems "just work". :-)
138  */
139 
140 /*
141  * Some machines require the "reboot=b" or "reboot=k"  commandline options,
142  * this quirk makes that automatic.
143  */
set_bios_reboot(const struct dmi_system_id * d)144 static int __init set_bios_reboot(const struct dmi_system_id *d)
145 {
146 	if (reboot_type != BOOT_BIOS) {
147 		reboot_type = BOOT_BIOS;
148 		printk(KERN_INFO "%s series board detected. Selecting BIOS-method for reboots.\n", d->ident);
149 	}
150 	return 0;
151 }
152 
set_kbd_reboot(const struct dmi_system_id * d)153 static int __init set_kbd_reboot(const struct dmi_system_id *d)
154 {
155 	if (reboot_type != BOOT_KBD) {
156 		reboot_type = BOOT_KBD;
157 		printk(KERN_INFO "%s series board detected. Selecting KBD-method for reboot.\n", d->ident);
158 	}
159 	return 0;
160 }
161 
162 static struct dmi_system_id __initdata reboot_dmi_table[] = {
163 	{	/* Handle problems with rebooting on Dell E520's */
164 		.callback = set_bios_reboot,
165 		.ident = "Dell E520",
166 		.matches = {
167 			DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
168 			DMI_MATCH(DMI_PRODUCT_NAME, "Dell DM061"),
169 		},
170 	},
171 	{	/* Handle problems with rebooting on Dell 1300's */
172 		.callback = set_bios_reboot,
173 		.ident = "Dell PowerEdge 1300",
174 		.matches = {
175 			DMI_MATCH(DMI_SYS_VENDOR, "Dell Computer Corporation"),
176 			DMI_MATCH(DMI_PRODUCT_NAME, "PowerEdge 1300/"),
177 		},
178 	},
179 	{	/* Handle problems with rebooting on Dell 300's */
180 		.callback = set_bios_reboot,
181 		.ident = "Dell PowerEdge 300",
182 		.matches = {
183 			DMI_MATCH(DMI_SYS_VENDOR, "Dell Computer Corporation"),
184 			DMI_MATCH(DMI_PRODUCT_NAME, "PowerEdge 300/"),
185 		},
186 	},
187 	{       /* Handle problems with rebooting on Dell Optiplex 745's SFF*/
188 		.callback = set_bios_reboot,
189 		.ident = "Dell OptiPlex 745",
190 		.matches = {
191 			DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
192 			DMI_MATCH(DMI_PRODUCT_NAME, "OptiPlex 745"),
193 		},
194 	},
195 	{       /* Handle problems with rebooting on Dell Optiplex 745's DFF*/
196 		.callback = set_bios_reboot,
197 		.ident = "Dell OptiPlex 745",
198 		.matches = {
199 			DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
200 			DMI_MATCH(DMI_PRODUCT_NAME, "OptiPlex 745"),
201 			DMI_MATCH(DMI_BOARD_NAME, "0MM599"),
202 		},
203 	},
204 	{       /* Handle problems with rebooting on Dell Optiplex 745 with 0KW626 */
205 		.callback = set_bios_reboot,
206 		.ident = "Dell OptiPlex 745",
207 		.matches = {
208 			DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
209 			DMI_MATCH(DMI_PRODUCT_NAME, "OptiPlex 745"),
210 			DMI_MATCH(DMI_BOARD_NAME, "0KW626"),
211 		},
212 	},
213 	{   /* Handle problems with rebooting on Dell Optiplex 330 with 0KP561 */
214 		.callback = set_bios_reboot,
215 		.ident = "Dell OptiPlex 330",
216 		.matches = {
217 			DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
218 			DMI_MATCH(DMI_PRODUCT_NAME, "OptiPlex 330"),
219 			DMI_MATCH(DMI_BOARD_NAME, "0KP561"),
220 		},
221 	},
222 	{   /* Handle problems with rebooting on Dell Optiplex 360 with 0T656F */
223 		.callback = set_bios_reboot,
224 		.ident = "Dell OptiPlex 360",
225 		.matches = {
226 			DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
227 			DMI_MATCH(DMI_PRODUCT_NAME, "OptiPlex 360"),
228 			DMI_MATCH(DMI_BOARD_NAME, "0T656F"),
229 		},
230 	},
231 	{	/* Handle problems with rebooting on Dell OptiPlex 760 with 0G919G*/
232 		.callback = set_bios_reboot,
233 		.ident = "Dell OptiPlex 760",
234 		.matches = {
235 			DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
236 			DMI_MATCH(DMI_PRODUCT_NAME, "OptiPlex 760"),
237 			DMI_MATCH(DMI_BOARD_NAME, "0G919G"),
238 		},
239 	},
240 	{	/* Handle problems with rebooting on Dell 2400's */
241 		.callback = set_bios_reboot,
242 		.ident = "Dell PowerEdge 2400",
243 		.matches = {
244 			DMI_MATCH(DMI_SYS_VENDOR, "Dell Computer Corporation"),
245 			DMI_MATCH(DMI_PRODUCT_NAME, "PowerEdge 2400"),
246 		},
247 	},
248 	{	/* Handle problems with rebooting on Dell T5400's */
249 		.callback = set_bios_reboot,
250 		.ident = "Dell Precision T5400",
251 		.matches = {
252 			DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
253 			DMI_MATCH(DMI_PRODUCT_NAME, "Precision WorkStation T5400"),
254 		},
255 	},
256 	{	/* Handle problems with rebooting on Dell T7400's */
257 		.callback = set_bios_reboot,
258 		.ident = "Dell Precision T7400",
259 		.matches = {
260 			DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
261 			DMI_MATCH(DMI_PRODUCT_NAME, "Precision WorkStation T7400"),
262 		},
263 	},
264 	{	/* Handle problems with rebooting on HP laptops */
265 		.callback = set_bios_reboot,
266 		.ident = "HP Compaq Laptop",
267 		.matches = {
268 			DMI_MATCH(DMI_SYS_VENDOR, "Hewlett-Packard"),
269 			DMI_MATCH(DMI_PRODUCT_NAME, "HP Compaq"),
270 		},
271 	},
272 	{	/* Handle problems with rebooting on Dell XPS710 */
273 		.callback = set_bios_reboot,
274 		.ident = "Dell XPS710",
275 		.matches = {
276 			DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
277 			DMI_MATCH(DMI_PRODUCT_NAME, "Dell XPS710"),
278 		},
279 	},
280 	{	/* Handle problems with rebooting on Dell DXP061 */
281 		.callback = set_bios_reboot,
282 		.ident = "Dell DXP061",
283 		.matches = {
284 			DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
285 			DMI_MATCH(DMI_PRODUCT_NAME, "Dell DXP061"),
286 		},
287 	},
288 	{	/* Handle problems with rebooting on Sony VGN-Z540N */
289 		.callback = set_bios_reboot,
290 		.ident = "Sony VGN-Z540N",
291 		.matches = {
292 			DMI_MATCH(DMI_SYS_VENDOR, "Sony Corporation"),
293 			DMI_MATCH(DMI_PRODUCT_NAME, "VGN-Z540N"),
294 		},
295 	},
296 	{	/* Handle problems with rebooting on CompuLab SBC-FITPC2 */
297 		.callback = set_bios_reboot,
298 		.ident = "CompuLab SBC-FITPC2",
299 		.matches = {
300 			DMI_MATCH(DMI_SYS_VENDOR, "CompuLab"),
301 			DMI_MATCH(DMI_PRODUCT_NAME, "SBC-FITPC2"),
302 		},
303 	},
304 	{       /* Handle problems with rebooting on ASUS P4S800 */
305 		.callback = set_bios_reboot,
306 		.ident = "ASUS P4S800",
307 		.matches = {
308 			DMI_MATCH(DMI_BOARD_VENDOR, "ASUSTeK Computer INC."),
309 			DMI_MATCH(DMI_BOARD_NAME, "P4S800"),
310 		},
311 	},
312 	{ /* Handle reboot issue on Acer Aspire one */
313 		.callback = set_kbd_reboot,
314 		.ident = "Acer Aspire One A110",
315 		.matches = {
316 			DMI_MATCH(DMI_SYS_VENDOR, "Acer"),
317 			DMI_MATCH(DMI_PRODUCT_NAME, "AOA110"),
318 		},
319 	},
320 	{ }
321 };
322 
reboot_init(void)323 static int __init reboot_init(void)
324 {
325 	/* Only do the DMI check if reboot_type hasn't been overridden
326 	 * on the command line
327 	 */
328 	if (reboot_default) {
329 		dmi_check_system(reboot_dmi_table);
330 	}
331 	return 0;
332 }
333 core_initcall(reboot_init);
334 
335 extern const unsigned char machine_real_restart_asm[];
336 extern const u64 machine_real_restart_gdt[3];
337 
machine_real_restart(unsigned int type)338 void machine_real_restart(unsigned int type)
339 {
340 	void *restart_va;
341 	unsigned long restart_pa;
342 	void (*restart_lowmem)(unsigned int);
343 	u64 *lowmem_gdt;
344 
345 	local_irq_disable();
346 
347 	/* Write zero to CMOS register number 0x0f, which the BIOS POST
348 	   routine will recognize as telling it to do a proper reboot.  (Well
349 	   that's what this book in front of me says -- it may only apply to
350 	   the Phoenix BIOS though, it's not clear).  At the same time,
351 	   disable NMIs by setting the top bit in the CMOS address register,
352 	   as we're about to do peculiar things to the CPU.  I'm not sure if
353 	   `outb_p' is needed instead of just `outb'.  Use it to be on the
354 	   safe side.  (Yes, CMOS_WRITE does outb_p's. -  Paul G.)
355 	 */
356 	spin_lock(&rtc_lock);
357 	CMOS_WRITE(0x00, 0x8f);
358 	spin_unlock(&rtc_lock);
359 
360 	/*
361 	 * Switch back to the initial page table.
362 	 */
363 	load_cr3(initial_page_table);
364 
365 	/* Write 0x1234 to absolute memory location 0x472.  The BIOS reads
366 	   this on booting to tell it to "Bypass memory test (also warm
367 	   boot)".  This seems like a fairly standard thing that gets set by
368 	   REBOOT.COM programs, and the previous reset routine did this
369 	   too. */
370 	*((unsigned short *)0x472) = reboot_mode;
371 
372 	/* Patch the GDT in the low memory trampoline */
373 	lowmem_gdt = TRAMPOLINE_SYM(machine_real_restart_gdt);
374 
375 	restart_va = TRAMPOLINE_SYM(machine_real_restart_asm);
376 	restart_pa = virt_to_phys(restart_va);
377 	restart_lowmem = (void (*)(unsigned int))restart_pa;
378 
379 	/* GDT[0]: GDT self-pointer */
380 	lowmem_gdt[0] =
381 		(u64)(sizeof(machine_real_restart_gdt) - 1) +
382 		((u64)virt_to_phys(lowmem_gdt) << 16);
383 	/* GDT[1]: 64K real mode code segment */
384 	lowmem_gdt[1] =
385 		GDT_ENTRY(0x009b, restart_pa, 0xffff);
386 
387 	/* Jump to the identity-mapped low memory code */
388 	restart_lowmem(type);
389 }
390 #ifdef CONFIG_APM_MODULE
391 EXPORT_SYMBOL(machine_real_restart);
392 #endif
393 
394 #endif /* CONFIG_X86_32 */
395 
396 /*
397  * Some Apple MacBook and MacBookPro's needs reboot=p to be able to reboot
398  */
set_pci_reboot(const struct dmi_system_id * d)399 static int __init set_pci_reboot(const struct dmi_system_id *d)
400 {
401 	if (reboot_type != BOOT_CF9) {
402 		reboot_type = BOOT_CF9;
403 		printk(KERN_INFO "%s series board detected. "
404 		       "Selecting PCI-method for reboots.\n", d->ident);
405 	}
406 	return 0;
407 }
408 
409 static struct dmi_system_id __initdata pci_reboot_dmi_table[] = {
410 	{	/* Handle problems with rebooting on Apple MacBook5 */
411 		.callback = set_pci_reboot,
412 		.ident = "Apple MacBook5",
413 		.matches = {
414 			DMI_MATCH(DMI_SYS_VENDOR, "Apple Inc."),
415 			DMI_MATCH(DMI_PRODUCT_NAME, "MacBook5"),
416 		},
417 	},
418 	{	/* Handle problems with rebooting on Apple MacBookPro5 */
419 		.callback = set_pci_reboot,
420 		.ident = "Apple MacBookPro5",
421 		.matches = {
422 			DMI_MATCH(DMI_SYS_VENDOR, "Apple Inc."),
423 			DMI_MATCH(DMI_PRODUCT_NAME, "MacBookPro5"),
424 		},
425 	},
426 	{	/* Handle problems with rebooting on Apple Macmini3,1 */
427 		.callback = set_pci_reboot,
428 		.ident = "Apple Macmini3,1",
429 		.matches = {
430 			DMI_MATCH(DMI_SYS_VENDOR, "Apple Inc."),
431 			DMI_MATCH(DMI_PRODUCT_NAME, "Macmini3,1"),
432 		},
433 	},
434 	{	/* Handle problems with rebooting on the iMac9,1. */
435 		.callback = set_pci_reboot,
436 		.ident = "Apple iMac9,1",
437 		.matches = {
438 			DMI_MATCH(DMI_SYS_VENDOR, "Apple Inc."),
439 			DMI_MATCH(DMI_PRODUCT_NAME, "iMac9,1"),
440 		},
441 	},
442 	{	/* Handle problems with rebooting on the Latitude E6320. */
443 		.callback = set_pci_reboot,
444 		.ident = "Dell Latitude E6320",
445 		.matches = {
446 			DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
447 			DMI_MATCH(DMI_PRODUCT_NAME, "Latitude E6320"),
448 		},
449 	},
450 	{	/* Handle problems with rebooting on the Latitude E5420. */
451 		.callback = set_pci_reboot,
452 		.ident = "Dell Latitude E5420",
453 		.matches = {
454 			DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
455 			DMI_MATCH(DMI_PRODUCT_NAME, "Latitude E5420"),
456 		},
457 	},
458 	{	/* Handle problems with rebooting on the Latitude E6420. */
459 		.callback = set_pci_reboot,
460 		.ident = "Dell Latitude E6420",
461 		.matches = {
462 			DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
463 			DMI_MATCH(DMI_PRODUCT_NAME, "Latitude E6420"),
464 		},
465 	},
466 	{	/* Handle problems with rebooting on the OptiPlex 990. */
467 		.callback = set_pci_reboot,
468 		.ident = "Dell OptiPlex 990",
469 		.matches = {
470 			DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
471 			DMI_MATCH(DMI_PRODUCT_NAME, "OptiPlex 990"),
472 		},
473 	},
474 	{	/* Handle problems with rebooting on the Precision M6600. */
475 		.callback = set_pci_reboot,
476 		.ident = "Dell OptiPlex 990",
477 		.matches = {
478 			DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
479 			DMI_MATCH(DMI_PRODUCT_NAME, "Precision M6600"),
480 		},
481 	},
482 	{	/* Handle problems with rebooting on the Dell PowerEdge C6100. */
483 		.callback = set_pci_reboot,
484 		.ident = "Dell PowerEdge C6100",
485 		.matches = {
486 			DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
487 			DMI_MATCH(DMI_PRODUCT_NAME, "C6100"),
488 		},
489 	},
490 	{	/* Some C6100 machines were shipped with vendor being 'Dell'. */
491 		.callback = set_pci_reboot,
492 		.ident = "Dell PowerEdge C6100",
493 		.matches = {
494 			DMI_MATCH(DMI_SYS_VENDOR, "Dell"),
495 			DMI_MATCH(DMI_PRODUCT_NAME, "C6100"),
496 		},
497 	},
498 	{ }
499 };
500 
pci_reboot_init(void)501 static int __init pci_reboot_init(void)
502 {
503 	/* Only do the DMI check if reboot_type hasn't been overridden
504 	 * on the command line
505 	 */
506 	if (reboot_default) {
507 		dmi_check_system(pci_reboot_dmi_table);
508 	}
509 	return 0;
510 }
511 core_initcall(pci_reboot_init);
512 
kb_wait(void)513 static inline void kb_wait(void)
514 {
515 	int i;
516 
517 	for (i = 0; i < 0x10000; i++) {
518 		if ((inb(0x64) & 0x02) == 0)
519 			break;
520 		udelay(2);
521 	}
522 }
523 
vmxoff_nmi(int cpu,struct pt_regs * regs)524 static void vmxoff_nmi(int cpu, struct pt_regs *regs)
525 {
526 	cpu_emergency_vmxoff();
527 }
528 
529 /* Use NMIs as IPIs to tell all CPUs to disable virtualization
530  */
emergency_vmx_disable_all(void)531 static void emergency_vmx_disable_all(void)
532 {
533 	/* Just make sure we won't change CPUs while doing this */
534 	local_irq_disable();
535 
536 	/* We need to disable VMX on all CPUs before rebooting, otherwise
537 	 * we risk hanging up the machine, because the CPU ignore INIT
538 	 * signals when VMX is enabled.
539 	 *
540 	 * We can't take any locks and we may be on an inconsistent
541 	 * state, so we use NMIs as IPIs to tell the other CPUs to disable
542 	 * VMX and halt.
543 	 *
544 	 * For safety, we will avoid running the nmi_shootdown_cpus()
545 	 * stuff unnecessarily, but we don't have a way to check
546 	 * if other CPUs have VMX enabled. So we will call it only if the
547 	 * CPU we are running on has VMX enabled.
548 	 *
549 	 * We will miss cases where VMX is not enabled on all CPUs. This
550 	 * shouldn't do much harm because KVM always enable VMX on all
551 	 * CPUs anyway. But we can miss it on the small window where KVM
552 	 * is still enabling VMX.
553 	 */
554 	if (cpu_has_vmx() && cpu_vmx_enabled()) {
555 		/* Disable VMX on this CPU.
556 		 */
557 		cpu_vmxoff();
558 
559 		/* Halt and disable VMX on the other CPUs */
560 		nmi_shootdown_cpus(vmxoff_nmi);
561 
562 	}
563 }
564 
565 
mach_reboot_fixups(void)566 void __attribute__((weak)) mach_reboot_fixups(void)
567 {
568 }
569 
570 /*
571  * Windows compatible x86 hardware expects the following on reboot:
572  *
573  * 1) If the FADT has the ACPI reboot register flag set, try it
574  * 2) If still alive, write to the keyboard controller
575  * 3) If still alive, write to the ACPI reboot register again
576  * 4) If still alive, write to the keyboard controller again
577  *
578  * If the machine is still alive at this stage, it gives up. We default to
579  * following the same pattern, except that if we're still alive after (4) we'll
580  * try to force a triple fault and then cycle between hitting the keyboard
581  * controller and doing that
582  */
native_machine_emergency_restart(void)583 static void native_machine_emergency_restart(void)
584 {
585 	int i;
586 	int attempt = 0;
587 	int orig_reboot_type = reboot_type;
588 
589 	if (reboot_emergency)
590 		emergency_vmx_disable_all();
591 
592 	tboot_shutdown(TB_SHUTDOWN_REBOOT);
593 
594 	/* Tell the BIOS if we want cold or warm reboot */
595 	*((unsigned short *)__va(0x472)) = reboot_mode;
596 
597 	for (;;) {
598 		/* Could also try the reset bit in the Hammer NB */
599 		switch (reboot_type) {
600 		case BOOT_KBD:
601 			mach_reboot_fixups(); /* for board specific fixups */
602 
603 			for (i = 0; i < 10; i++) {
604 				kb_wait();
605 				udelay(50);
606 				outb(0xfe, 0x64); /* pulse reset low */
607 				udelay(50);
608 			}
609 			if (attempt == 0 && orig_reboot_type == BOOT_ACPI) {
610 				attempt = 1;
611 				reboot_type = BOOT_ACPI;
612 			} else {
613 				reboot_type = BOOT_TRIPLE;
614 			}
615 			break;
616 
617 		case BOOT_TRIPLE:
618 			load_idt(&no_idt);
619 			__asm__ __volatile__("int3");
620 
621 			reboot_type = BOOT_KBD;
622 			break;
623 
624 #ifdef CONFIG_X86_32
625 		case BOOT_BIOS:
626 			machine_real_restart(MRR_BIOS);
627 
628 			reboot_type = BOOT_KBD;
629 			break;
630 #endif
631 
632 		case BOOT_ACPI:
633 			acpi_reboot();
634 			reboot_type = BOOT_KBD;
635 			break;
636 
637 		case BOOT_EFI:
638 			if (efi_enabled(EFI_RUNTIME_SERVICES))
639 				efi.reset_system(reboot_mode ?
640 						 EFI_RESET_WARM :
641 						 EFI_RESET_COLD,
642 						 EFI_SUCCESS, 0, NULL);
643 			reboot_type = BOOT_KBD;
644 			break;
645 
646 		case BOOT_CF9:
647 			port_cf9_safe = true;
648 			/* fall through */
649 
650 		case BOOT_CF9_COND:
651 			if (port_cf9_safe) {
652 				u8 cf9 = inb(0xcf9) & ~6;
653 				outb(cf9|2, 0xcf9); /* Request hard reset */
654 				udelay(50);
655 				outb(cf9|6, 0xcf9); /* Actually do the reset */
656 				udelay(50);
657 			}
658 			reboot_type = BOOT_KBD;
659 			break;
660 		}
661 	}
662 }
663 
native_machine_shutdown(void)664 void native_machine_shutdown(void)
665 {
666 	/* Stop the cpus and apics */
667 #ifdef CONFIG_SMP
668 
669 	/* The boot cpu is always logical cpu 0 */
670 	int reboot_cpu_id = 0;
671 
672 #ifdef CONFIG_X86_32
673 	/* See if there has been given a command line override */
674 	if ((reboot_cpu != -1) && (reboot_cpu < nr_cpu_ids) &&
675 		cpu_online(reboot_cpu))
676 		reboot_cpu_id = reboot_cpu;
677 #endif
678 
679 	/* Make certain the cpu I'm about to reboot on is online */
680 	if (!cpu_online(reboot_cpu_id))
681 		reboot_cpu_id = smp_processor_id();
682 
683 	/* Make certain I only run on the appropriate processor */
684 	set_cpus_allowed_ptr(current, cpumask_of(reboot_cpu_id));
685 
686 	/* O.K Now that I'm on the appropriate processor,
687 	 * stop all of the others.
688 	 */
689 	stop_other_cpus();
690 #endif
691 
692 	lapic_shutdown();
693 
694 #ifdef CONFIG_X86_IO_APIC
695 	disable_IO_APIC();
696 #endif
697 
698 #ifdef CONFIG_HPET_TIMER
699 	hpet_disable();
700 #endif
701 
702 #ifdef CONFIG_X86_64
703 	x86_platform.iommu_shutdown();
704 #endif
705 }
706 
__machine_emergency_restart(int emergency)707 static void __machine_emergency_restart(int emergency)
708 {
709 	reboot_emergency = emergency;
710 	machine_ops.emergency_restart();
711 }
712 
native_machine_restart(char * __unused)713 static void native_machine_restart(char *__unused)
714 {
715 	printk("machine restart\n");
716 
717 	if (!reboot_force)
718 		machine_shutdown();
719 	__machine_emergency_restart(0);
720 }
721 
native_machine_halt(void)722 static void native_machine_halt(void)
723 {
724 	/* stop other cpus and apics */
725 	machine_shutdown();
726 
727 	tboot_shutdown(TB_SHUTDOWN_HALT);
728 
729 	/* stop this cpu */
730 	stop_this_cpu(NULL);
731 }
732 
native_machine_power_off(void)733 static void native_machine_power_off(void)
734 {
735 	if (pm_power_off) {
736 		if (!reboot_force)
737 			machine_shutdown();
738 		pm_power_off();
739 	}
740 	/* a fallback in case there is no PM info available */
741 	tboot_shutdown(TB_SHUTDOWN_HALT);
742 }
743 
744 struct machine_ops machine_ops = {
745 	.power_off = native_machine_power_off,
746 	.shutdown = native_machine_shutdown,
747 	.emergency_restart = native_machine_emergency_restart,
748 	.restart = native_machine_restart,
749 	.halt = native_machine_halt,
750 #ifdef CONFIG_KEXEC
751 	.crash_shutdown = native_machine_crash_shutdown,
752 #endif
753 };
754 
machine_power_off(void)755 void machine_power_off(void)
756 {
757 	machine_ops.power_off();
758 }
759 
machine_shutdown(void)760 void machine_shutdown(void)
761 {
762 	machine_ops.shutdown();
763 }
764 
machine_emergency_restart(void)765 void machine_emergency_restart(void)
766 {
767 	__machine_emergency_restart(1);
768 }
769 
machine_restart(char * cmd)770 void machine_restart(char *cmd)
771 {
772 	machine_ops.restart(cmd);
773 }
774 
machine_halt(void)775 void machine_halt(void)
776 {
777 	machine_ops.halt();
778 }
779 
780 #ifdef CONFIG_KEXEC
machine_crash_shutdown(struct pt_regs * regs)781 void machine_crash_shutdown(struct pt_regs *regs)
782 {
783 	machine_ops.crash_shutdown(regs);
784 }
785 #endif
786 
787 
788 #if defined(CONFIG_SMP)
789 
790 /* This keeps a track of which one is crashing cpu. */
791 static int crashing_cpu;
792 static nmi_shootdown_cb shootdown_callback;
793 
794 static atomic_t waiting_for_crash_ipi;
795 
crash_nmi_callback(unsigned int val,struct pt_regs * regs)796 static int crash_nmi_callback(unsigned int val, struct pt_regs *regs)
797 {
798 	int cpu;
799 
800 	cpu = raw_smp_processor_id();
801 
802 	/* Don't do anything if this handler is invoked on crashing cpu.
803 	 * Otherwise, system will completely hang. Crashing cpu can get
804 	 * an NMI if system was initially booted with nmi_watchdog parameter.
805 	 */
806 	if (cpu == crashing_cpu)
807 		return NMI_HANDLED;
808 	local_irq_disable();
809 
810 	shootdown_callback(cpu, regs);
811 
812 	atomic_dec(&waiting_for_crash_ipi);
813 	/* Assume hlt works */
814 	halt();
815 	for (;;)
816 		cpu_relax();
817 
818 	return NMI_HANDLED;
819 }
820 
smp_send_nmi_allbutself(void)821 static void smp_send_nmi_allbutself(void)
822 {
823 	apic->send_IPI_allbutself(NMI_VECTOR);
824 }
825 
826 /* Halt all other CPUs, calling the specified function on each of them
827  *
828  * This function can be used to halt all other CPUs on crash
829  * or emergency reboot time. The function passed as parameter
830  * will be called inside a NMI handler on all CPUs.
831  */
nmi_shootdown_cpus(nmi_shootdown_cb callback)832 void nmi_shootdown_cpus(nmi_shootdown_cb callback)
833 {
834 	unsigned long msecs;
835 	local_irq_disable();
836 
837 	/* Make a note of crashing cpu. Will be used in NMI callback.*/
838 	crashing_cpu = safe_smp_processor_id();
839 
840 	shootdown_callback = callback;
841 
842 	atomic_set(&waiting_for_crash_ipi, num_online_cpus() - 1);
843 	/* Would it be better to replace the trap vector here? */
844 	if (register_nmi_handler(NMI_LOCAL, crash_nmi_callback,
845 				 NMI_FLAG_FIRST, "crash"))
846 		return;		/* return what? */
847 	/* Ensure the new callback function is set before sending
848 	 * out the NMI
849 	 */
850 	wmb();
851 
852 	smp_send_nmi_allbutself();
853 
854 	msecs = 1000; /* Wait at most a second for the other cpus to stop */
855 	while ((atomic_read(&waiting_for_crash_ipi) > 0) && msecs) {
856 		mdelay(1);
857 		msecs--;
858 	}
859 
860 	/* Leave the nmi callback set */
861 }
862 #else /* !CONFIG_SMP */
nmi_shootdown_cpus(nmi_shootdown_cb callback)863 void nmi_shootdown_cpus(nmi_shootdown_cb callback)
864 {
865 	/* No other CPUs to shoot down */
866 }
867 #endif
868