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v3.1
 
 
  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 */
 34void (*pm_power_off)(void);
 35EXPORT_SYMBOL(pm_power_off);
 36
 37static const struct desc_ptr no_idt = {};
 38static int reboot_mode;
 39enum reboot_type reboot_type = BOOT_ACPI;
 40int reboot_force;
 41
 42#if defined(CONFIG_X86_32) && defined(CONFIG_SMP)
 43static int reboot_cpu = -1;
 44#endif
 45
 46/* This is set if we need to go through the 'emergency' path.
 47 * When machine_emergency_restart() is called, we may be on
 48 * an inconsistent state and won't be able to do a clean cleanup
 49 */
 50static int reboot_emergency;
 51
 52/* This is set by the PCI code if either type 1 or type 2 PCI is detected */
 53bool port_cf9_safe = false;
 54
 55/* reboot=b[ios] | s[mp] | t[riple] | k[bd] | e[fi] [, [w]arm | [c]old] | p[ci]
 56   warm   Don't set the cold reboot flag
 57   cold   Set the cold reboot flag
 58   bios   Reboot by jumping through the BIOS (only for X86_32)
 59   smp    Reboot by executing reset on BSP or other CPU (only for X86_32)
 60   triple Force a triple fault (init)
 61   kbd    Use the keyboard controller. cold reset (default)
 62   acpi   Use the RESET_REG in the FADT
 63   efi    Use efi reset_system runtime service
 64   pci    Use the so-called "PCI reset register", CF9
 65   force  Avoid anything that could hang.
 66 */
 67static int __init reboot_setup(char *str)
 68{
 69	for (;;) {
 70		switch (*str) {
 71		case 'w':
 72			reboot_mode = 0x1234;
 73			break;
 
 
 74
 75		case 'c':
 76			reboot_mode = 0;
 77			break;
 78
 79#ifdef CONFIG_X86_32
 80#ifdef CONFIG_SMP
 81		case 's':
 82			if (isdigit(*(str+1))) {
 83				reboot_cpu = (int) (*(str+1) - '0');
 84				if (isdigit(*(str+2)))
 85					reboot_cpu = reboot_cpu*10 + (int)(*(str+2) - '0');
 86			}
 87				/* we will leave sorting out the final value
 88				   when we are ready to reboot, since we might not
 89				   have detected BSP APIC ID or smp_num_cpu */
 90			break;
 91#endif /* CONFIG_SMP */
 92
 93		case 'b':
 
 
 
 
 
 
 94#endif
 95		case 'a':
 96		case 'k':
 97		case 't':
 98		case 'e':
 99		case 'p':
100			reboot_type = *str;
101			break;
102
103		case 'f':
104			reboot_force = 1;
105			break;
106		}
107
108		str = strchr(str, ',');
109		if (str)
110			str++;
111		else
112			break;
113	}
114	return 1;
 
 
 
 
115}
 
 
 
116
117__setup("reboot=", reboot_setup);
118
119
120#ifdef CONFIG_X86_32
121/*
122 * Reboot options and system auto-detection code provided by
123 * Dell Inc. so their systems "just work". :-)
124 */
 
 
 
 
 
 
 
 
 
125
126/*
127 * Some machines require the "reboot=b"  commandline option,
128 * this quirk makes that automatic.
129 */
130static int __init set_bios_reboot(const struct dmi_system_id *d)
131{
132	if (reboot_type != BOOT_BIOS) {
133		reboot_type = BOOT_BIOS;
134		printk(KERN_INFO "%s series board detected. Selecting BIOS-method for reboots.\n", d->ident);
 
135	}
136	return 0;
137}
138
 
 
 
139static struct dmi_system_id __initdata reboot_dmi_table[] = {
140	{	/* Handle problems with rebooting on Dell E520's */
141		.callback = set_bios_reboot,
142		.ident = "Dell E520",
 
 
143		.matches = {
144			DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
145			DMI_MATCH(DMI_PRODUCT_NAME, "Dell DM061"),
146		},
147	},
148	{	/* Handle problems with rebooting on Dell 1300's */
149		.callback = set_bios_reboot,
150		.ident = "Dell PowerEdge 1300",
 
 
151		.matches = {
152			DMI_MATCH(DMI_SYS_VENDOR, "Dell Computer Corporation"),
153			DMI_MATCH(DMI_PRODUCT_NAME, "PowerEdge 1300/"),
154		},
155	},
156	{	/* Handle problems with rebooting on Dell 300's */
157		.callback = set_bios_reboot,
158		.ident = "Dell PowerEdge 300",
159		.matches = {
160			DMI_MATCH(DMI_SYS_VENDOR, "Dell Computer Corporation"),
161			DMI_MATCH(DMI_PRODUCT_NAME, "PowerEdge 300/"),
162		},
163	},
164	{       /* Handle problems with rebooting on Dell Optiplex 745's SFF*/
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
165		.callback = set_bios_reboot,
166		.ident = "Dell OptiPlex 745",
167		.matches = {
168			DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
169			DMI_MATCH(DMI_PRODUCT_NAME, "OptiPlex 745"),
 
 
 
 
 
 
 
 
 
 
170		},
171	},
172	{       /* Handle problems with rebooting on Dell Optiplex 745's DFF*/
 
 
173		.callback = set_bios_reboot,
174		.ident = "Dell OptiPlex 745",
175		.matches = {
176			DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
177			DMI_MATCH(DMI_PRODUCT_NAME, "OptiPlex 745"),
178			DMI_MATCH(DMI_BOARD_NAME, "0MM599"),
179		},
180	},
181	{       /* Handle problems with rebooting on Dell Optiplex 745 with 0KW626 */
182		.callback = set_bios_reboot,
183		.ident = "Dell OptiPlex 745",
184		.matches = {
185			DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
186			DMI_MATCH(DMI_PRODUCT_NAME, "OptiPlex 745"),
187			DMI_MATCH(DMI_BOARD_NAME, "0KW626"),
188		},
189	},
190	{   /* Handle problems with rebooting on Dell Optiplex 330 with 0KP561 */
191		.callback = set_bios_reboot,
192		.ident = "Dell OptiPlex 330",
193		.matches = {
194			DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
195			DMI_MATCH(DMI_PRODUCT_NAME, "OptiPlex 330"),
196			DMI_MATCH(DMI_BOARD_NAME, "0KP561"),
197		},
198	},
199	{   /* Handle problems with rebooting on Dell Optiplex 360 with 0T656F */
200		.callback = set_bios_reboot,
201		.ident = "Dell OptiPlex 360",
202		.matches = {
203			DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
204			DMI_MATCH(DMI_PRODUCT_NAME, "OptiPlex 360"),
205			DMI_MATCH(DMI_BOARD_NAME, "0T656F"),
206		},
207	},
208	{	/* Handle problems with rebooting on Dell OptiPlex 760 with 0G919G*/
209		.callback = set_bios_reboot,
210		.ident = "Dell OptiPlex 760",
211		.matches = {
212			DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
213			DMI_MATCH(DMI_PRODUCT_NAME, "OptiPlex 760"),
214			DMI_MATCH(DMI_BOARD_NAME, "0G919G"),
215		},
216	},
217	{	/* Handle problems with rebooting on Dell 2400's */
218		.callback = set_bios_reboot,
219		.ident = "Dell PowerEdge 2400",
220		.matches = {
221			DMI_MATCH(DMI_SYS_VENDOR, "Dell Computer Corporation"),
222			DMI_MATCH(DMI_PRODUCT_NAME, "PowerEdge 2400"),
223		},
224	},
225	{	/* Handle problems with rebooting on Dell T5400's */
226		.callback = set_bios_reboot,
227		.ident = "Dell Precision T5400",
228		.matches = {
229			DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
230			DMI_MATCH(DMI_PRODUCT_NAME, "Precision WorkStation T5400"),
 
231		},
232	},
233	{	/* Handle problems with rebooting on Dell T7400's */
234		.callback = set_bios_reboot,
235		.ident = "Dell Precision T7400",
236		.matches = {
237			DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
238			DMI_MATCH(DMI_PRODUCT_NAME, "Precision WorkStation T7400"),
 
239		},
240	},
241	{	/* Handle problems with rebooting on HP laptops */
242		.callback = set_bios_reboot,
243		.ident = "HP Compaq Laptop",
244		.matches = {
245			DMI_MATCH(DMI_SYS_VENDOR, "Hewlett-Packard"),
246			DMI_MATCH(DMI_PRODUCT_NAME, "HP Compaq"),
247		},
248	},
249	{	/* Handle problems with rebooting on Dell XPS710 */
250		.callback = set_bios_reboot,
251		.ident = "Dell XPS710",
252		.matches = {
253			DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
254			DMI_MATCH(DMI_PRODUCT_NAME, "Dell XPS710"),
 
255		},
256	},
257	{	/* Handle problems with rebooting on Dell DXP061 */
258		.callback = set_bios_reboot,
259		.ident = "Dell DXP061",
260		.matches = {
261			DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
262			DMI_MATCH(DMI_PRODUCT_NAME, "Dell DXP061"),
 
263		},
264	},
265	{	/* Handle problems with rebooting on Sony VGN-Z540N */
266		.callback = set_bios_reboot,
267		.ident = "Sony VGN-Z540N",
268		.matches = {
269			DMI_MATCH(DMI_SYS_VENDOR, "Sony Corporation"),
270			DMI_MATCH(DMI_PRODUCT_NAME, "VGN-Z540N"),
 
271		},
272	},
273	{	/* Handle problems with rebooting on CompuLab SBC-FITPC2 */
274		.callback = set_bios_reboot,
275		.ident = "CompuLab SBC-FITPC2",
276		.matches = {
277			DMI_MATCH(DMI_SYS_VENDOR, "CompuLab"),
278			DMI_MATCH(DMI_PRODUCT_NAME, "SBC-FITPC2"),
279		},
280	},
281	{       /* Handle problems with rebooting on ASUS P4S800 */
282		.callback = set_bios_reboot,
283		.ident = "ASUS P4S800",
284		.matches = {
285			DMI_MATCH(DMI_BOARD_VENDOR, "ASUSTeK Computer INC."),
286			DMI_MATCH(DMI_BOARD_NAME, "P4S800"),
287		},
288	},
289	{	/* Handle problems with rebooting on VersaLogic Menlow boards */
290		.callback = set_bios_reboot,
291		.ident = "VersaLogic Menlow based board",
292		.matches = {
293			DMI_MATCH(DMI_BOARD_VENDOR, "VersaLogic Corporation"),
294			DMI_MATCH(DMI_BOARD_NAME, "VersaLogic Menlow board"),
295		},
296	},
297	{ /* Handle reboot issue on Acer Aspire one */
298		.callback = set_bios_reboot,
299		.ident = "Acer Aspire One A110",
300		.matches = {
301			DMI_MATCH(DMI_SYS_VENDOR, "Acer"),
302			DMI_MATCH(DMI_PRODUCT_NAME, "AOA110"),
303		},
304	},
305	{ }
306};
307
308static int __init reboot_init(void)
309{
310	dmi_check_system(reboot_dmi_table);
311	return 0;
312}
313core_initcall(reboot_init);
314
315extern const unsigned char machine_real_restart_asm[];
316extern const u64 machine_real_restart_gdt[3];
317
318void machine_real_restart(unsigned int type)
319{
320	void *restart_va;
321	unsigned long restart_pa;
322	void (*restart_lowmem)(unsigned int);
323	u64 *lowmem_gdt;
324
325	local_irq_disable();
326
327	/* Write zero to CMOS register number 0x0f, which the BIOS POST
328	   routine will recognize as telling it to do a proper reboot.  (Well
329	   that's what this book in front of me says -- it may only apply to
330	   the Phoenix BIOS though, it's not clear).  At the same time,
331	   disable NMIs by setting the top bit in the CMOS address register,
332	   as we're about to do peculiar things to the CPU.  I'm not sure if
333	   `outb_p' is needed instead of just `outb'.  Use it to be on the
334	   safe side.  (Yes, CMOS_WRITE does outb_p's. -  Paul G.)
335	 */
336	spin_lock(&rtc_lock);
337	CMOS_WRITE(0x00, 0x8f);
338	spin_unlock(&rtc_lock);
339
340	/*
341	 * Switch back to the initial page table.
342	 */
343	load_cr3(initial_page_table);
344
345	/* Write 0x1234 to absolute memory location 0x472.  The BIOS reads
346	   this on booting to tell it to "Bypass memory test (also warm
347	   boot)".  This seems like a fairly standard thing that gets set by
348	   REBOOT.COM programs, and the previous reset routine did this
349	   too. */
350	*((unsigned short *)0x472) = reboot_mode;
351
352	/* Patch the GDT in the low memory trampoline */
353	lowmem_gdt = TRAMPOLINE_SYM(machine_real_restart_gdt);
354
355	restart_va = TRAMPOLINE_SYM(machine_real_restart_asm);
356	restart_pa = virt_to_phys(restart_va);
357	restart_lowmem = (void (*)(unsigned int))restart_pa;
358
359	/* GDT[0]: GDT self-pointer */
360	lowmem_gdt[0] =
361		(u64)(sizeof(machine_real_restart_gdt) - 1) +
362		((u64)virt_to_phys(lowmem_gdt) << 16);
363	/* GDT[1]: 64K real mode code segment */
364	lowmem_gdt[1] =
365		GDT_ENTRY(0x009b, restart_pa, 0xffff);
366
367	/* Jump to the identity-mapped low memory code */
368	restart_lowmem(type);
369}
370#ifdef CONFIG_APM_MODULE
371EXPORT_SYMBOL(machine_real_restart);
372#endif
373
374#endif /* CONFIG_X86_32 */
375
376/*
377 * Some Apple MacBook and MacBookPro's needs reboot=p to be able to reboot
378 */
379static int __init set_pci_reboot(const struct dmi_system_id *d)
380{
381	if (reboot_type != BOOT_CF9) {
382		reboot_type = BOOT_CF9;
383		printk(KERN_INFO "%s series board detected. "
384		       "Selecting PCI-method for reboots.\n", d->ident);
385	}
386	return 0;
387}
388
389static struct dmi_system_id __initdata pci_reboot_dmi_table[] = {
390	{	/* Handle problems with rebooting on Apple MacBook5 */
391		.callback = set_pci_reboot,
392		.ident = "Apple MacBook5",
393		.matches = {
394			DMI_MATCH(DMI_SYS_VENDOR, "Apple Inc."),
395			DMI_MATCH(DMI_PRODUCT_NAME, "MacBook5"),
396		},
397	},
398	{	/* Handle problems with rebooting on Apple MacBookPro5 */
399		.callback = set_pci_reboot,
400		.ident = "Apple MacBookPro5",
401		.matches = {
402			DMI_MATCH(DMI_SYS_VENDOR, "Apple Inc."),
403			DMI_MATCH(DMI_PRODUCT_NAME, "MacBookPro5"),
404		},
405	},
406	{	/* Handle problems with rebooting on Apple Macmini3,1 */
407		.callback = set_pci_reboot,
408		.ident = "Apple Macmini3,1",
409		.matches = {
410			DMI_MATCH(DMI_SYS_VENDOR, "Apple Inc."),
411			DMI_MATCH(DMI_PRODUCT_NAME, "Macmini3,1"),
412		},
413	},
414	{	/* Handle problems with rebooting on the iMac9,1. */
415		.callback = set_pci_reboot,
416		.ident = "Apple iMac9,1",
417		.matches = {
418			DMI_MATCH(DMI_SYS_VENDOR, "Apple Inc."),
419			DMI_MATCH(DMI_PRODUCT_NAME, "iMac9,1"),
420		},
421	},
422	{	/* Handle problems with rebooting on the Latitude E6320. */
423		.callback = set_pci_reboot,
424		.ident = "Dell Latitude E6320",
425		.matches = {
426			DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
427			DMI_MATCH(DMI_PRODUCT_NAME, "Latitude E6320"),
428		},
429	},
430	{	/* Handle problems with rebooting on the Latitude E5420. */
431		.callback = set_pci_reboot,
432		.ident = "Dell Latitude E5420",
 
 
433		.matches = {
434			DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
435			DMI_MATCH(DMI_PRODUCT_NAME, "Latitude E5420"),
436		},
437	},
438	{	/* Handle problems with rebooting on the Latitude E6420. */
439		.callback = set_pci_reboot,
440		.ident = "Dell Latitude E6420",
 
 
441		.matches = {
442			DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
443			DMI_MATCH(DMI_PRODUCT_NAME, "Latitude E6420"),
444		},
445	},
 
446	{ }
447};
448
449static int __init pci_reboot_init(void)
450{
451	dmi_check_system(pci_reboot_dmi_table);
 
 
 
 
 
452	return 0;
453}
454core_initcall(pci_reboot_init);
455
456static inline void kb_wait(void)
457{
458	int i;
459
460	for (i = 0; i < 0x10000; i++) {
461		if ((inb(0x64) & 0x02) == 0)
462			break;
463		udelay(2);
464	}
465}
466
467static void vmxoff_nmi(int cpu, struct die_args *args)
468{
469	cpu_emergency_vmxoff();
470}
471
472/* Use NMIs as IPIs to tell all CPUs to disable virtualization
473 */
474static void emergency_vmx_disable_all(void)
475{
476	/* Just make sure we won't change CPUs while doing this */
477	local_irq_disable();
478
479	/* We need to disable VMX on all CPUs before rebooting, otherwise
 
480	 * we risk hanging up the machine, because the CPU ignore INIT
481	 * signals when VMX is enabled.
482	 *
483	 * We can't take any locks and we may be on an inconsistent
484	 * state, so we use NMIs as IPIs to tell the other CPUs to disable
485	 * VMX and halt.
486	 *
487	 * For safety, we will avoid running the nmi_shootdown_cpus()
488	 * stuff unnecessarily, but we don't have a way to check
489	 * if other CPUs have VMX enabled. So we will call it only if the
490	 * CPU we are running on has VMX enabled.
491	 *
492	 * We will miss cases where VMX is not enabled on all CPUs. This
493	 * shouldn't do much harm because KVM always enable VMX on all
494	 * CPUs anyway. But we can miss it on the small window where KVM
495	 * is still enabling VMX.
496	 */
497	if (cpu_has_vmx() && cpu_vmx_enabled()) {
498		/* Disable VMX on this CPU.
499		 */
500		cpu_vmxoff();
501
502		/* Halt and disable VMX on the other CPUs */
503		nmi_shootdown_cpus(vmxoff_nmi);
504
505	}
506}
507
508
509void __attribute__((weak)) mach_reboot_fixups(void)
510{
511}
512
513/*
514 * Windows compatible x86 hardware expects the following on reboot:
 
515 *
516 * 1) If the FADT has the ACPI reboot register flag set, try it
517 * 2) If still alive, write to the keyboard controller
518 * 3) If still alive, write to the ACPI reboot register again
519 * 4) If still alive, write to the keyboard controller again
 
 
 
 
 
 
 
520 *
521 * If the machine is still alive at this stage, it gives up. We default to
522 * following the same pattern, except that if we're still alive after (4) we'll
523 * try to force a triple fault and then cycle between hitting the keyboard
524 * controller and doing that
525 */
526static void native_machine_emergency_restart(void)
527{
528	int i;
529	int attempt = 0;
530	int orig_reboot_type = reboot_type;
 
531
532	if (reboot_emergency)
533		emergency_vmx_disable_all();
534
535	tboot_shutdown(TB_SHUTDOWN_REBOOT);
536
537	/* Tell the BIOS if we want cold or warm reboot */
538	*((unsigned short *)__va(0x472)) = reboot_mode;
 
539
540	for (;;) {
541		/* Could also try the reset bit in the Hammer NB */
542		switch (reboot_type) {
 
 
 
 
 
543		case BOOT_KBD:
544			mach_reboot_fixups(); /* for board specific fixups */
545
546			for (i = 0; i < 10; i++) {
547				kb_wait();
548				udelay(50);
549				outb(0xfe, 0x64); /* pulse reset low */
550				udelay(50);
551			}
552			if (attempt == 0 && orig_reboot_type == BOOT_ACPI) {
553				attempt = 1;
554				reboot_type = BOOT_ACPI;
555			} else {
556				reboot_type = BOOT_TRIPLE;
557			}
558			break;
559
560		case BOOT_TRIPLE:
561			load_idt(&no_idt);
562			__asm__ __volatile__("int3");
563
564			reboot_type = BOOT_KBD;
 
 
565			break;
566
567#ifdef CONFIG_X86_32
568		case BOOT_BIOS:
569			machine_real_restart(MRR_BIOS);
570
571			reboot_type = BOOT_KBD;
572			break;
573#endif
574
575		case BOOT_ACPI:
576			acpi_reboot();
577			reboot_type = BOOT_KBD;
578			break;
579
580		case BOOT_EFI:
581			if (efi_enabled)
582				efi.reset_system(reboot_mode ?
583						 EFI_RESET_WARM :
584						 EFI_RESET_COLD,
585						 EFI_SUCCESS, 0, NULL);
586			reboot_type = BOOT_KBD;
587			break;
588
589		case BOOT_CF9:
590			port_cf9_safe = true;
591			/* fall through */
592
593		case BOOT_CF9_COND:
594			if (port_cf9_safe) {
595				u8 cf9 = inb(0xcf9) & ~6;
 
596				outb(cf9|2, 0xcf9); /* Request hard reset */
597				udelay(50);
598				outb(cf9|6, 0xcf9); /* Actually do the reset */
 
599				udelay(50);
600			}
 
 
 
 
 
 
 
 
601			reboot_type = BOOT_KBD;
602			break;
603		}
604	}
605}
606
607void native_machine_shutdown(void)
608{
609	/* Stop the cpus and apics */
610#ifdef CONFIG_SMP
611
612	/* The boot cpu is always logical cpu 0 */
613	int reboot_cpu_id = 0;
614
615#ifdef CONFIG_X86_32
616	/* See if there has been given a command line override */
617	if ((reboot_cpu != -1) && (reboot_cpu < nr_cpu_ids) &&
618		cpu_online(reboot_cpu))
619		reboot_cpu_id = reboot_cpu;
 
 
 
620#endif
621
622	/* Make certain the cpu I'm about to reboot on is online */
623	if (!cpu_online(reboot_cpu_id))
624		reboot_cpu_id = smp_processor_id();
625
626	/* Make certain I only run on the appropriate processor */
627	set_cpus_allowed_ptr(current, cpumask_of(reboot_cpu_id));
628
629	/* O.K Now that I'm on the appropriate processor,
630	 * stop all of the others.
631	 */
 
632	stop_other_cpus();
633#endif
634
635	lapic_shutdown();
636
637#ifdef CONFIG_X86_IO_APIC
638	disable_IO_APIC();
639#endif
640
641#ifdef CONFIG_HPET_TIMER
642	hpet_disable();
643#endif
644
645#ifdef CONFIG_X86_64
646	x86_platform.iommu_shutdown();
647#endif
648}
649
650static void __machine_emergency_restart(int emergency)
651{
652	reboot_emergency = emergency;
653	machine_ops.emergency_restart();
654}
655
656static void native_machine_restart(char *__unused)
657{
658	printk("machine restart\n");
659
660	if (!reboot_force)
661		machine_shutdown();
662	__machine_emergency_restart(0);
663}
664
665static void native_machine_halt(void)
666{
667	/* stop other cpus and apics */
668	machine_shutdown();
669
670	tboot_shutdown(TB_SHUTDOWN_HALT);
671
672	/* stop this cpu */
673	stop_this_cpu(NULL);
674}
675
676static void native_machine_power_off(void)
677{
678	if (pm_power_off) {
679		if (!reboot_force)
680			machine_shutdown();
681		pm_power_off();
682	}
683	/* a fallback in case there is no PM info available */
684	tboot_shutdown(TB_SHUTDOWN_HALT);
685}
686
687struct machine_ops machine_ops = {
688	.power_off = native_machine_power_off,
689	.shutdown = native_machine_shutdown,
690	.emergency_restart = native_machine_emergency_restart,
691	.restart = native_machine_restart,
692	.halt = native_machine_halt,
693#ifdef CONFIG_KEXEC
694	.crash_shutdown = native_machine_crash_shutdown,
695#endif
696};
697
698void machine_power_off(void)
699{
700	machine_ops.power_off();
701}
702
703void machine_shutdown(void)
704{
705	machine_ops.shutdown();
706}
707
708void machine_emergency_restart(void)
709{
710	__machine_emergency_restart(1);
711}
712
713void machine_restart(char *cmd)
714{
715	machine_ops.restart(cmd);
716}
717
718void machine_halt(void)
719{
720	machine_ops.halt();
721}
722
723#ifdef CONFIG_KEXEC
724void machine_crash_shutdown(struct pt_regs *regs)
725{
726	machine_ops.crash_shutdown(regs);
727}
728#endif
729
730
731#if defined(CONFIG_SMP)
732
733/* This keeps a track of which one is crashing cpu. */
734static int crashing_cpu;
735static nmi_shootdown_cb shootdown_callback;
736
737static atomic_t waiting_for_crash_ipi;
738
739static int crash_nmi_callback(struct notifier_block *self,
740			unsigned long val, void *data)
741{
742	int cpu;
743
744	if (val != DIE_NMI)
745		return NOTIFY_OK;
746
747	cpu = raw_smp_processor_id();
748
749	/* Don't do anything if this handler is invoked on crashing cpu.
 
750	 * Otherwise, system will completely hang. Crashing cpu can get
751	 * an NMI if system was initially booted with nmi_watchdog parameter.
752	 */
753	if (cpu == crashing_cpu)
754		return NOTIFY_STOP;
755	local_irq_disable();
756
757	shootdown_callback(cpu, (struct die_args *)data);
758
759	atomic_dec(&waiting_for_crash_ipi);
760	/* Assume hlt works */
761	halt();
762	for (;;)
763		cpu_relax();
764
765	return 1;
766}
767
768static void smp_send_nmi_allbutself(void)
769{
770	apic->send_IPI_allbutself(NMI_VECTOR);
771}
772
773static struct notifier_block crash_nmi_nb = {
774	.notifier_call = crash_nmi_callback,
775	/* we want to be the first one called */
776	.priority = NMI_LOCAL_HIGH_PRIOR+1,
777};
778
779/* Halt all other CPUs, calling the specified function on each of them
780 *
781 * This function can be used to halt all other CPUs on crash
782 * or emergency reboot time. The function passed as parameter
783 * will be called inside a NMI handler on all CPUs.
784 */
785void nmi_shootdown_cpus(nmi_shootdown_cb callback)
786{
787	unsigned long msecs;
788	local_irq_disable();
789
790	/* Make a note of crashing cpu. Will be used in NMI callback.*/
791	crashing_cpu = safe_smp_processor_id();
792
793	shootdown_callback = callback;
794
795	atomic_set(&waiting_for_crash_ipi, num_online_cpus() - 1);
796	/* Would it be better to replace the trap vector here? */
797	if (register_die_notifier(&crash_nmi_nb))
798		return;		/* return what? */
799	/* Ensure the new callback function is set before sending
 
 
800	 * out the NMI
801	 */
802	wmb();
803
804	smp_send_nmi_allbutself();
805
806	msecs = 1000; /* Wait at most a second for the other cpus to stop */
807	while ((atomic_read(&waiting_for_crash_ipi) > 0) && msecs) {
808		mdelay(1);
809		msecs--;
810	}
811
812	/* Leave the nmi callback set */
813}
814#else /* !CONFIG_SMP */
815void nmi_shootdown_cpus(nmi_shootdown_cb callback)
816{
817	/* No other CPUs to shoot down */
818}
819#endif
v3.15
  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/desc.h>
 16#include <asm/hpet.h>
 17#include <asm/pgtable.h>
 18#include <asm/proto.h>
 19#include <asm/reboot_fixups.h>
 20#include <asm/reboot.h>
 21#include <asm/pci_x86.h>
 22#include <asm/virtext.h>
 23#include <asm/cpu.h>
 24#include <asm/nmi.h>
 25#include <asm/smp.h>
 26
 27#include <linux/ctype.h>
 28#include <linux/mc146818rtc.h>
 29#include <asm/realmode.h>
 30#include <asm/x86_init.h>
 
 
 31
 32/*
 33 * Power off function, if any
 34 */
 35void (*pm_power_off)(void);
 36EXPORT_SYMBOL(pm_power_off);
 37
 38static const struct desc_ptr no_idt = {};
 
 
 
 39
 40/*
 41 * This is set if we need to go through the 'emergency' path.
 
 
 
 42 * When machine_emergency_restart() is called, we may be on
 43 * an inconsistent state and won't be able to do a clean cleanup
 44 */
 45static int reboot_emergency;
 46
 47/* This is set by the PCI code if either type 1 or type 2 PCI is detected */
 48bool port_cf9_safe = false;
 49
 50/*
 51 * Reboot options and system auto-detection code provided by
 52 * Dell Inc. so their systems "just work". :-)
 53 */
 54
 55/*
 56 * Some machines require the "reboot=b" or "reboot=k"  commandline options,
 57 * this quirk makes that automatic.
 
 
 
 58 */
 59static int __init set_bios_reboot(const struct dmi_system_id *d)
 60{
 61	if (reboot_type != BOOT_BIOS) {
 62		reboot_type = BOOT_BIOS;
 63		pr_info("%s series board detected. Selecting %s-method for reboots.\n",
 64			d->ident, "BIOS");
 65	}
 66	return 0;
 67}
 68
 69void __noreturn machine_real_restart(unsigned int type)
 70{
 71	local_irq_disable();
 72
 73	/*
 74	 * Write zero to CMOS register number 0x0f, which the BIOS POST
 75	 * routine will recognize as telling it to do a proper reboot.  (Well
 76	 * that's what this book in front of me says -- it may only apply to
 77	 * the Phoenix BIOS though, it's not clear).  At the same time,
 78	 * disable NMIs by setting the top bit in the CMOS address register,
 79	 * as we're about to do peculiar things to the CPU.  I'm not sure if
 80	 * `outb_p' is needed instead of just `outb'.  Use it to be on the
 81	 * safe side.  (Yes, CMOS_WRITE does outb_p's. -  Paul G.)
 82	 */
 83	spin_lock(&rtc_lock);
 84	CMOS_WRITE(0x00, 0x8f);
 85	spin_unlock(&rtc_lock);
 86
 87	/*
 88	 * Switch back to the initial page table.
 89	 */
 90#ifdef CONFIG_X86_32
 91	load_cr3(initial_page_table);
 92#else
 93	write_cr3(real_mode_header->trampoline_pgd);
 94#endif
 
 
 
 
 
 
 
 
 
 
 
 
 95
 96	/* Jump to the identity-mapped low memory code */
 97#ifdef CONFIG_X86_32
 98	asm volatile("jmpl *%0" : :
 99		     "rm" (real_mode_header->machine_real_restart_asm),
100		     "a" (type));
101#else
102	asm volatile("ljmpl *%0" : :
103		     "m" (real_mode_header->machine_real_restart_asm),
104		     "D" (type));
105#endif
106	unreachable();
107}
108#ifdef CONFIG_APM_MODULE
109EXPORT_SYMBOL(machine_real_restart);
110#endif
111
 
 
 
 
112/*
113 * Some Apple MacBook and MacBookPro's needs reboot=p to be able to reboot
 
114 */
115static int __init set_pci_reboot(const struct dmi_system_id *d)
116{
117	if (reboot_type != BOOT_CF9_FORCE) {
118		reboot_type = BOOT_CF9_FORCE;
119		pr_info("%s series board detected. Selecting %s-method for reboots.\n",
120			d->ident, "PCI");
121	}
122	return 0;
123}
124
125static int __init set_kbd_reboot(const struct dmi_system_id *d)
 
 
 
 
126{
127	if (reboot_type != BOOT_KBD) {
128		reboot_type = BOOT_KBD;
129		pr_info("%s series board detected. Selecting %s-method for reboot.\n",
130			d->ident, "KBD");
131	}
132	return 0;
133}
134
135/*
136 * This is a single dmi_table handling all reboot quirks.
137 */
138static struct dmi_system_id __initdata reboot_dmi_table[] = {
139
140	/* Acer */
141	{	/* Handle reboot issue on Acer Aspire one */
142		.callback = set_kbd_reboot,
143		.ident = "Acer Aspire One A110",
144		.matches = {
145			DMI_MATCH(DMI_SYS_VENDOR, "Acer"),
146			DMI_MATCH(DMI_PRODUCT_NAME, "AOA110"),
147		},
148	},
149
150	/* Apple */
151	{	/* Handle problems with rebooting on Apple MacBook5 */
152		.callback = set_pci_reboot,
153		.ident = "Apple MacBook5",
154		.matches = {
155			DMI_MATCH(DMI_SYS_VENDOR, "Apple Inc."),
156			DMI_MATCH(DMI_PRODUCT_NAME, "MacBook5"),
157		},
158	},
159	{	/* Handle problems with rebooting on Apple MacBookPro5 */
160		.callback = set_pci_reboot,
161		.ident = "Apple MacBookPro5",
162		.matches = {
163			DMI_MATCH(DMI_SYS_VENDOR, "Apple Inc."),
164			DMI_MATCH(DMI_PRODUCT_NAME, "MacBookPro5"),
165		},
166	},
167	{	/* Handle problems with rebooting on Apple Macmini3,1 */
168		.callback = set_pci_reboot,
169		.ident = "Apple Macmini3,1",
170		.matches = {
171			DMI_MATCH(DMI_SYS_VENDOR, "Apple Inc."),
172			DMI_MATCH(DMI_PRODUCT_NAME, "Macmini3,1"),
173		},
174	},
175	{	/* Handle problems with rebooting on the iMac9,1. */
176		.callback = set_pci_reboot,
177		.ident = "Apple iMac9,1",
178		.matches = {
179			DMI_MATCH(DMI_SYS_VENDOR, "Apple Inc."),
180			DMI_MATCH(DMI_PRODUCT_NAME, "iMac9,1"),
181		},
182	},
183
184	/* ASUS */
185	{	/* Handle problems with rebooting on ASUS P4S800 */
186		.callback = set_bios_reboot,
187		.ident = "ASUS P4S800",
188		.matches = {
189			DMI_MATCH(DMI_BOARD_VENDOR, "ASUSTeK Computer INC."),
190			DMI_MATCH(DMI_BOARD_NAME, "P4S800"),
191		},
192	},
193
194	/* Certec */
195	{       /* Handle problems with rebooting on Certec BPC600 */
196		.callback = set_pci_reboot,
197		.ident = "Certec BPC600",
198		.matches = {
199			DMI_MATCH(DMI_SYS_VENDOR, "Certec"),
200			DMI_MATCH(DMI_PRODUCT_NAME, "BPC600"),
201		},
202	},
203
204	/* Dell */
205	{	/* Handle problems with rebooting on Dell DXP061 */
206		.callback = set_bios_reboot,
207		.ident = "Dell DXP061",
208		.matches = {
209			DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
210			DMI_MATCH(DMI_PRODUCT_NAME, "Dell DXP061"),
 
211		},
212	},
213	{	/* Handle problems with rebooting on Dell E520's */
214		.callback = set_bios_reboot,
215		.ident = "Dell E520",
216		.matches = {
217			DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
218			DMI_MATCH(DMI_PRODUCT_NAME, "Dell DM061"),
 
219		},
220	},
221	{	/* Handle problems with rebooting on the Latitude E5410. */
222		.callback = set_pci_reboot,
223		.ident = "Dell Latitude E5410",
224		.matches = {
225			DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
226			DMI_MATCH(DMI_PRODUCT_NAME, "Latitude E5410"),
 
227		},
228	},
229	{	/* Handle problems with rebooting on the Latitude E5420. */
230		.callback = set_pci_reboot,
231		.ident = "Dell Latitude E5420",
232		.matches = {
233			DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
234			DMI_MATCH(DMI_PRODUCT_NAME, "Latitude E5420"),
 
235		},
236	},
237	{	/* Handle problems with rebooting on the Latitude E6320. */
238		.callback = set_pci_reboot,
239		.ident = "Dell Latitude E6320",
240		.matches = {
241			DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
242			DMI_MATCH(DMI_PRODUCT_NAME, "Latitude E6320"),
 
243		},
244	},
245	{	/* Handle problems with rebooting on the Latitude E6420. */
246		.callback = set_pci_reboot,
247		.ident = "Dell Latitude E6420",
248		.matches = {
249			DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
250			DMI_MATCH(DMI_PRODUCT_NAME, "Latitude E6420"),
251		},
252	},
253	{	/* Handle problems with rebooting on Dell Optiplex 330 with 0KP561 */
254		.callback = set_bios_reboot,
255		.ident = "Dell OptiPlex 330",
256		.matches = {
257			DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
258			DMI_MATCH(DMI_PRODUCT_NAME, "OptiPlex 330"),
259			DMI_MATCH(DMI_BOARD_NAME, "0KP561"),
260		},
261	},
262	{	/* Handle problems with rebooting on Dell Optiplex 360 with 0T656F */
263		.callback = set_bios_reboot,
264		.ident = "Dell OptiPlex 360",
265		.matches = {
266			DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
267			DMI_MATCH(DMI_PRODUCT_NAME, "OptiPlex 360"),
268			DMI_MATCH(DMI_BOARD_NAME, "0T656F"),
269		},
270	},
271	{	/* Handle problems with rebooting on Dell Optiplex 745's SFF */
272		.callback = set_bios_reboot,
273		.ident = "Dell OptiPlex 745",
274		.matches = {
275			DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
276			DMI_MATCH(DMI_PRODUCT_NAME, "OptiPlex 745"),
277		},
278	},
279	{	/* Handle problems with rebooting on Dell Optiplex 745's DFF */
280		.callback = set_bios_reboot,
281		.ident = "Dell OptiPlex 745",
282		.matches = {
283			DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
284			DMI_MATCH(DMI_PRODUCT_NAME, "OptiPlex 745"),
285			DMI_MATCH(DMI_BOARD_NAME, "0MM599"),
286		},
287	},
288	{	/* Handle problems with rebooting on Dell Optiplex 745 with 0KW626 */
289		.callback = set_bios_reboot,
290		.ident = "Dell OptiPlex 745",
291		.matches = {
292			DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
293			DMI_MATCH(DMI_PRODUCT_NAME, "OptiPlex 745"),
294			DMI_MATCH(DMI_BOARD_NAME, "0KW626"),
295		},
296	},
297	{	/* Handle problems with rebooting on Dell OptiPlex 760 with 0G919G */
298		.callback = set_bios_reboot,
299		.ident = "Dell OptiPlex 760",
300		.matches = {
301			DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
302			DMI_MATCH(DMI_PRODUCT_NAME, "OptiPlex 760"),
303			DMI_MATCH(DMI_BOARD_NAME, "0G919G"),
304		},
305	},
306	{	/* Handle problems with rebooting on the OptiPlex 990. */
307		.callback = set_pci_reboot,
308		.ident = "Dell OptiPlex 990",
309		.matches = {
310			DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
311			DMI_MATCH(DMI_PRODUCT_NAME, "OptiPlex 990"),
312		},
313	},
314	{	/* Handle problems with rebooting on Dell 300's */
315		.callback = set_bios_reboot,
316		.ident = "Dell PowerEdge 300",
317		.matches = {
318			DMI_MATCH(DMI_SYS_VENDOR, "Dell Computer Corporation"),
319			DMI_MATCH(DMI_PRODUCT_NAME, "PowerEdge 300/"),
320		},
321	},
322	{	/* Handle problems with rebooting on Dell 1300's */
323		.callback = set_bios_reboot,
324		.ident = "Dell PowerEdge 1300",
325		.matches = {
326			DMI_MATCH(DMI_SYS_VENDOR, "Dell Computer Corporation"),
327			DMI_MATCH(DMI_PRODUCT_NAME, "PowerEdge 1300/"),
328		},
329	},
330	{	/* Handle problems with rebooting on Dell 2400's */
331		.callback = set_bios_reboot,
332		.ident = "Dell PowerEdge 2400",
333		.matches = {
334			DMI_MATCH(DMI_SYS_VENDOR, "Dell Computer Corporation"),
335			DMI_MATCH(DMI_PRODUCT_NAME, "PowerEdge 2400"),
336		},
337	},
338	{	/* Handle problems with rebooting on the Dell PowerEdge C6100. */
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
339		.callback = set_pci_reboot,
340		.ident = "Dell PowerEdge C6100",
341		.matches = {
342			DMI_MATCH(DMI_SYS_VENDOR, "Dell"),
343			DMI_MATCH(DMI_PRODUCT_NAME, "C6100"),
344		},
345	},
346	{	/* Handle problems with rebooting on the Precision M6600. */
347		.callback = set_pci_reboot,
348		.ident = "Dell Precision M6600",
349		.matches = {
350			DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
351			DMI_MATCH(DMI_PRODUCT_NAME, "Precision M6600"),
352		},
353	},
354	{	/* Handle problems with rebooting on Dell T5400's */
355		.callback = set_bios_reboot,
356		.ident = "Dell Precision T5400",
357		.matches = {
358			DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
359			DMI_MATCH(DMI_PRODUCT_NAME, "Precision WorkStation T5400"),
360		},
361	},
362	{	/* Handle problems with rebooting on Dell T7400's */
363		.callback = set_bios_reboot,
364		.ident = "Dell Precision T7400",
365		.matches = {
366			DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
367			DMI_MATCH(DMI_PRODUCT_NAME, "Precision WorkStation T7400"),
368		},
369	},
370	{	/* Handle problems with rebooting on Dell XPS710 */
371		.callback = set_bios_reboot,
372		.ident = "Dell XPS710",
373		.matches = {
374			DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
375			DMI_MATCH(DMI_PRODUCT_NAME, "Dell XPS710"),
376		},
377	},
378
379	/* Hewlett-Packard */
380	{	/* Handle problems with rebooting on HP laptops */
381		.callback = set_bios_reboot,
382		.ident = "HP Compaq Laptop",
383		.matches = {
384			DMI_MATCH(DMI_SYS_VENDOR, "Hewlett-Packard"),
385			DMI_MATCH(DMI_PRODUCT_NAME, "HP Compaq"),
386		},
387	},
388
389	/* Sony */
390	{	/* Handle problems with rebooting on Sony VGN-Z540N */
391		.callback = set_bios_reboot,
392		.ident = "Sony VGN-Z540N",
393		.matches = {
394			DMI_MATCH(DMI_SYS_VENDOR, "Sony Corporation"),
395			DMI_MATCH(DMI_PRODUCT_NAME, "VGN-Z540N"),
396		},
397	},
398
399	{ }
400};
401
402static int __init reboot_init(void)
403{
404	/*
405	 * Only do the DMI check if reboot_type hasn't been overridden
406	 * on the command line
407	 */
408	if (reboot_default)
409		dmi_check_system(reboot_dmi_table);
410	return 0;
411}
412core_initcall(reboot_init);
413
414static inline void kb_wait(void)
415{
416	int i;
417
418	for (i = 0; i < 0x10000; i++) {
419		if ((inb(0x64) & 0x02) == 0)
420			break;
421		udelay(2);
422	}
423}
424
425static void vmxoff_nmi(int cpu, struct pt_regs *regs)
426{
427	cpu_emergency_vmxoff();
428}
429
430/* Use NMIs as IPIs to tell all CPUs to disable virtualization */
 
431static void emergency_vmx_disable_all(void)
432{
433	/* Just make sure we won't change CPUs while doing this */
434	local_irq_disable();
435
436	/*
437	 * We need to disable VMX on all CPUs before rebooting, otherwise
438	 * we risk hanging up the machine, because the CPU ignore INIT
439	 * signals when VMX is enabled.
440	 *
441	 * We can't take any locks and we may be on an inconsistent
442	 * state, so we use NMIs as IPIs to tell the other CPUs to disable
443	 * VMX and halt.
444	 *
445	 * For safety, we will avoid running the nmi_shootdown_cpus()
446	 * stuff unnecessarily, but we don't have a way to check
447	 * if other CPUs have VMX enabled. So we will call it only if the
448	 * CPU we are running on has VMX enabled.
449	 *
450	 * We will miss cases where VMX is not enabled on all CPUs. This
451	 * shouldn't do much harm because KVM always enable VMX on all
452	 * CPUs anyway. But we can miss it on the small window where KVM
453	 * is still enabling VMX.
454	 */
455	if (cpu_has_vmx() && cpu_vmx_enabled()) {
456		/* Disable VMX on this CPU. */
 
457		cpu_vmxoff();
458
459		/* Halt and disable VMX on the other CPUs */
460		nmi_shootdown_cpus(vmxoff_nmi);
461
462	}
463}
464
465
466void __attribute__((weak)) mach_reboot_fixups(void)
467{
468}
469
470/*
471 * To the best of our knowledge Windows compatible x86 hardware expects
472 * the following on reboot:
473 *
474 * 1) If the FADT has the ACPI reboot register flag set, try it
475 * 2) If still alive, write to the keyboard controller
476 * 3) If still alive, write to the ACPI reboot register again
477 * 4) If still alive, write to the keyboard controller again
478 * 5) If still alive, call the EFI runtime service to reboot
479 * 6) If no EFI runtime service, call the BIOS to do a reboot
480 *
481 * We default to following the same pattern. We also have
482 * two other reboot methods: 'triple fault' and 'PCI', which
483 * can be triggered via the reboot= kernel boot option or
484 * via quirks.
485 *
486 * This means that this function can never return, it can misbehave
487 * by not rebooting properly and hanging.
 
 
488 */
489static void native_machine_emergency_restart(void)
490{
491	int i;
492	int attempt = 0;
493	int orig_reboot_type = reboot_type;
494	unsigned short mode;
495
496	if (reboot_emergency)
497		emergency_vmx_disable_all();
498
499	tboot_shutdown(TB_SHUTDOWN_REBOOT);
500
501	/* Tell the BIOS if we want cold or warm reboot */
502	mode = reboot_mode == REBOOT_WARM ? 0x1234 : 0;
503	*((unsigned short *)__va(0x472)) = mode;
504
505	for (;;) {
506		/* Could also try the reset bit in the Hammer NB */
507		switch (reboot_type) {
508		case BOOT_ACPI:
509			acpi_reboot();
510			reboot_type = BOOT_KBD;
511			break;
512
513		case BOOT_KBD:
514			mach_reboot_fixups(); /* For board specific fixups */
515
516			for (i = 0; i < 10; i++) {
517				kb_wait();
518				udelay(50);
519				outb(0xfe, 0x64); /* Pulse reset low */
520				udelay(50);
521			}
522			if (attempt == 0 && orig_reboot_type == BOOT_ACPI) {
523				attempt = 1;
524				reboot_type = BOOT_ACPI;
525			} else {
526				reboot_type = BOOT_EFI;
527			}
528			break;
529
530		case BOOT_EFI:
531			if (efi_enabled(EFI_RUNTIME_SERVICES))
532				efi.reset_system(reboot_mode == REBOOT_WARM ?
533						 EFI_RESET_WARM :
534						 EFI_RESET_COLD,
535						 EFI_SUCCESS, 0, NULL);
536			reboot_type = BOOT_BIOS;
537			break;
538
 
539		case BOOT_BIOS:
540			machine_real_restart(MRR_BIOS);
541
542			/* We're probably dead after this, but... */
543			reboot_type = BOOT_CF9_SAFE;
 
 
 
 
 
544			break;
545
546		case BOOT_CF9_FORCE:
 
 
 
 
 
 
 
 
 
547			port_cf9_safe = true;
548			/* Fall through */
549
550		case BOOT_CF9_SAFE:
551			if (port_cf9_safe) {
552				u8 reboot_code = reboot_mode == REBOOT_WARM ?  0x06 : 0x0E;
553				u8 cf9 = inb(0xcf9) & ~reboot_code;
554				outb(cf9|2, 0xcf9); /* Request hard reset */
555				udelay(50);
556				/* Actually do the reset */
557				outb(cf9|reboot_code, 0xcf9);
558				udelay(50);
559			}
560			reboot_type = BOOT_TRIPLE;
561			break;
562
563		case BOOT_TRIPLE:
564			load_idt(&no_idt);
565			__asm__ __volatile__("int3");
566
567			/* We're probably dead after this, but... */
568			reboot_type = BOOT_KBD;
569			break;
570		}
571	}
572}
573
574void native_machine_shutdown(void)
575{
576	/* Stop the cpus and apics */
577#ifdef CONFIG_X86_IO_APIC
578	/*
579	 * Disabling IO APIC before local APIC is a workaround for
580	 * erratum AVR31 in "Intel Atom Processor C2000 Product Family
581	 * Specification Update". In this situation, interrupts that target
582	 * a Logical Processor whose Local APIC is either in the process of
583	 * being hardware disabled or software disabled are neither delivered
584	 * nor discarded. When this erratum occurs, the processor may hang.
585	 *
586	 * Even without the erratum, it still makes sense to quiet IO APIC
587	 * before disabling Local APIC.
588	 */
589	disable_IO_APIC();
590#endif
591
592#ifdef CONFIG_SMP
593	/*
594	 * Stop all of the others. Also disable the local irq to
595	 * not receive the per-cpu timer interrupt which may trigger
596	 * scheduler's load balance.
 
 
 
 
597	 */
598	local_irq_disable();
599	stop_other_cpus();
600#endif
601
602	lapic_shutdown();
603
 
 
 
 
604#ifdef CONFIG_HPET_TIMER
605	hpet_disable();
606#endif
607
608#ifdef CONFIG_X86_64
609	x86_platform.iommu_shutdown();
610#endif
611}
612
613static void __machine_emergency_restart(int emergency)
614{
615	reboot_emergency = emergency;
616	machine_ops.emergency_restart();
617}
618
619static void native_machine_restart(char *__unused)
620{
621	pr_notice("machine restart\n");
622
623	if (!reboot_force)
624		machine_shutdown();
625	__machine_emergency_restart(0);
626}
627
628static void native_machine_halt(void)
629{
630	/* Stop other cpus and apics */
631	machine_shutdown();
632
633	tboot_shutdown(TB_SHUTDOWN_HALT);
634
 
635	stop_this_cpu(NULL);
636}
637
638static void native_machine_power_off(void)
639{
640	if (pm_power_off) {
641		if (!reboot_force)
642			machine_shutdown();
643		pm_power_off();
644	}
645	/* A fallback in case there is no PM info available */
646	tboot_shutdown(TB_SHUTDOWN_HALT);
647}
648
649struct machine_ops machine_ops = {
650	.power_off = native_machine_power_off,
651	.shutdown = native_machine_shutdown,
652	.emergency_restart = native_machine_emergency_restart,
653	.restart = native_machine_restart,
654	.halt = native_machine_halt,
655#ifdef CONFIG_KEXEC
656	.crash_shutdown = native_machine_crash_shutdown,
657#endif
658};
659
660void machine_power_off(void)
661{
662	machine_ops.power_off();
663}
664
665void machine_shutdown(void)
666{
667	machine_ops.shutdown();
668}
669
670void machine_emergency_restart(void)
671{
672	__machine_emergency_restart(1);
673}
674
675void machine_restart(char *cmd)
676{
677	machine_ops.restart(cmd);
678}
679
680void machine_halt(void)
681{
682	machine_ops.halt();
683}
684
685#ifdef CONFIG_KEXEC
686void machine_crash_shutdown(struct pt_regs *regs)
687{
688	machine_ops.crash_shutdown(regs);
689}
690#endif
691
692
693#if defined(CONFIG_SMP)
694
695/* This keeps a track of which one is crashing cpu. */
696static int crashing_cpu;
697static nmi_shootdown_cb shootdown_callback;
698
699static atomic_t waiting_for_crash_ipi;
700
701static int crash_nmi_callback(unsigned int val, struct pt_regs *regs)
 
702{
703	int cpu;
704
 
 
 
705	cpu = raw_smp_processor_id();
706
707	/*
708	 * Don't do anything if this handler is invoked on crashing cpu.
709	 * Otherwise, system will completely hang. Crashing cpu can get
710	 * an NMI if system was initially booted with nmi_watchdog parameter.
711	 */
712	if (cpu == crashing_cpu)
713		return NMI_HANDLED;
714	local_irq_disable();
715
716	shootdown_callback(cpu, regs);
717
718	atomic_dec(&waiting_for_crash_ipi);
719	/* Assume hlt works */
720	halt();
721	for (;;)
722		cpu_relax();
723
724	return NMI_HANDLED;
725}
726
727static void smp_send_nmi_allbutself(void)
728{
729	apic->send_IPI_allbutself(NMI_VECTOR);
730}
731
732/*
733 * Halt all other CPUs, calling the specified function on each of them
 
 
 
 
 
734 *
735 * This function can be used to halt all other CPUs on crash
736 * or emergency reboot time. The function passed as parameter
737 * will be called inside a NMI handler on all CPUs.
738 */
739void nmi_shootdown_cpus(nmi_shootdown_cb callback)
740{
741	unsigned long msecs;
742	local_irq_disable();
743
744	/* Make a note of crashing cpu. Will be used in NMI callback. */
745	crashing_cpu = safe_smp_processor_id();
746
747	shootdown_callback = callback;
748
749	atomic_set(&waiting_for_crash_ipi, num_online_cpus() - 1);
750	/* Would it be better to replace the trap vector here? */
751	if (register_nmi_handler(NMI_LOCAL, crash_nmi_callback,
752				 NMI_FLAG_FIRST, "crash"))
753		return;		/* Return what? */
754	/*
755	 * Ensure the new callback function is set before sending
756	 * out the NMI
757	 */
758	wmb();
759
760	smp_send_nmi_allbutself();
761
762	msecs = 1000; /* Wait at most a second for the other cpus to stop */
763	while ((atomic_read(&waiting_for_crash_ipi) > 0) && msecs) {
764		mdelay(1);
765		msecs--;
766	}
767
768	/* Leave the nmi callback set */
769}
770#else /* !CONFIG_SMP */
771void nmi_shootdown_cpus(nmi_shootdown_cb callback)
772{
773	/* No other CPUs to shoot down */
774}
775#endif