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v3.5.6
 
 
  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# include <asm/realmode.h>
 28#else
 29# include <asm/x86_init.h>
 30#endif
 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 = {};
 39static int reboot_mode;
 40enum reboot_type reboot_type = BOOT_ACPI;
 41int reboot_force;
 42
 43/*
 44 * This variable is used privately to keep track of whether or not
 45 * reboot_type is still set to its default value (i.e., reboot= hasn't
 46 * been set on the command line).  This is needed so that we can
 47 * suppress DMI scanning for reboot quirks.  Without it, it's
 48 * impossible to override a faulty reboot quirk without recompiling.
 49 */
 50static int reboot_default = 1;
 51
 52#if defined(CONFIG_X86_32) && defined(CONFIG_SMP)
 53static int reboot_cpu = -1;
 54#endif
 55
 56/*
 57 * This is set if we need to go through the 'emergency' path.
 58 * When machine_emergency_restart() is called, we may be on
 59 * an inconsistent state and won't be able to do a clean cleanup
 60 */
 61static int reboot_emergency;
 62
 63/* This is set by the PCI code if either type 1 or type 2 PCI is detected */
 64bool port_cf9_safe = false;
 65
 66/*
 67 * reboot=b[ios] | s[mp] | t[riple] | k[bd] | e[fi] [, [w]arm | [c]old] | p[ci]
 68 * warm   Don't set the cold reboot flag
 69 * cold   Set the cold reboot flag
 70 * bios   Reboot by jumping through the BIOS (only for X86_32)
 71 * smp    Reboot by executing reset on BSP or other CPU (only for X86_32)
 72 * triple Force a triple fault (init)
 73 * kbd    Use the keyboard controller. cold reset (default)
 74 * acpi   Use the RESET_REG in the FADT
 75 * efi    Use efi reset_system runtime service
 76 * pci    Use the so-called "PCI reset register", CF9
 77 * force  Avoid anything that could hang.
 78 */
 79static int __init reboot_setup(char *str)
 80{
 81	for (;;) {
 82		/*
 83		 * Having anything passed on the command line via
 84		 * reboot= will cause us to disable DMI checking
 85		 * below.
 86		 */
 87		reboot_default = 0;
 88
 89		switch (*str) {
 90		case 'w':
 91			reboot_mode = 0x1234;
 92			break;
 93
 94		case 'c':
 95			reboot_mode = 0;
 96			break;
 97
 98#ifdef CONFIG_X86_32
 99#ifdef CONFIG_SMP
100		case 's':
101			if (isdigit(*(str+1))) {
102				reboot_cpu = (int) (*(str+1) - '0');
103				if (isdigit(*(str+2)))
104					reboot_cpu = reboot_cpu*10 + (int)(*(str+2) - '0');
105			}
106			/*
107			 * We will leave sorting out the final value
108			 * when we are ready to reboot, since we might not
109			 * have detected BSP APIC ID or smp_num_cpu
110			 */
111			break;
112#endif /* CONFIG_SMP */
113
114		case 'b':
115#endif
116		case 'a':
117		case 'k':
118		case 't':
119		case 'e':
120		case 'p':
121			reboot_type = *str;
122			break;
123
124		case 'f':
125			reboot_force = 1;
126			break;
127		}
128
129		str = strchr(str, ',');
130		if (str)
131			str++;
132		else
133			break;
134	}
135	return 1;
136}
137
138__setup("reboot=", reboot_setup);
139
140
141#ifdef CONFIG_X86_32
142/*
143 * Reboot options and system auto-detection code provided by
144 * Dell Inc. so their systems "just work". :-)
145 */
146
147/*
148 * Some machines require the "reboot=b" or "reboot=k"  commandline options,
149 * this quirk makes that automatic.
150 */
151static int __init set_bios_reboot(const struct dmi_system_id *d)
152{
153	if (reboot_type != BOOT_BIOS) {
154		reboot_type = BOOT_BIOS;
155		printk(KERN_INFO "%s series board detected. Selecting BIOS-method for reboots.\n", d->ident);
 
156	}
157	return 0;
158}
159
160void machine_real_restart(unsigned int type)
161{
162	void (*restart_lowmem)(unsigned int) = (void (*)(unsigned int))
163		real_mode_header->machine_real_restart_asm;
164
165	local_irq_disable();
166
167	/*
168	 * Write zero to CMOS register number 0x0f, which the BIOS POST
169	 * routine will recognize as telling it to do a proper reboot.  (Well
170	 * that's what this book in front of me says -- it may only apply to
171	 * the Phoenix BIOS though, it's not clear).  At the same time,
172	 * disable NMIs by setting the top bit in the CMOS address register,
173	 * as we're about to do peculiar things to the CPU.  I'm not sure if
174	 * `outb_p' is needed instead of just `outb'.  Use it to be on the
175	 * safe side.  (Yes, CMOS_WRITE does outb_p's. -  Paul G.)
176	 */
177	spin_lock(&rtc_lock);
178	CMOS_WRITE(0x00, 0x8f);
179	spin_unlock(&rtc_lock);
180
181	/*
182	 * Switch back to the initial page table.
183	 */
 
184	load_cr3(initial_page_table);
185
186	/*
187	 * Write 0x1234 to absolute memory location 0x472.  The BIOS reads
188	 * this on booting to tell it to "Bypass memory test (also warm
189	 * boot)".  This seems like a fairly standard thing that gets set by
190	 * REBOOT.COM programs, and the previous reset routine did this
191	 * too. */
192	*((unsigned short *)0x472) = reboot_mode;
193
194	/* Jump to the identity-mapped low memory code */
195	restart_lowmem(type);
 
 
 
 
 
 
 
 
 
196}
197#ifdef CONFIG_APM_MODULE
198EXPORT_SYMBOL(machine_real_restart);
199#endif
200
201#endif /* CONFIG_X86_32 */
202
203/*
204 * Some Apple MacBook and MacBookPro's needs reboot=p to be able to reboot
205 */
206static int __init set_pci_reboot(const struct dmi_system_id *d)
207{
208	if (reboot_type != BOOT_CF9) {
209		reboot_type = BOOT_CF9;
210		printk(KERN_INFO "%s series board detected. "
211		       "Selecting PCI-method for reboots.\n", d->ident);
212	}
213	return 0;
214}
215
216static int __init set_kbd_reboot(const struct dmi_system_id *d)
217{
218	if (reboot_type != BOOT_KBD) {
219		reboot_type = BOOT_KBD;
220		printk(KERN_INFO "%s series board detected. Selecting KBD-method for reboot.\n", d->ident);
 
221	}
222	return 0;
223}
224
225/*
226 * This is a single dmi_table handling all reboot quirks.  Note that
227 * REBOOT_BIOS is only available for 32bit
228 */
229static struct dmi_system_id __initdata reboot_dmi_table[] = {
230#ifdef CONFIG_X86_32
231	{	/* Handle problems with rebooting on Dell E520's */
232		.callback = set_bios_reboot,
233		.ident = "Dell E520",
 
234		.matches = {
235			DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
236			DMI_MATCH(DMI_PRODUCT_NAME, "Dell DM061"),
237		},
238	},
239	{	/* Handle problems with rebooting on Dell 1300's */
240		.callback = set_bios_reboot,
241		.ident = "Dell PowerEdge 1300",
 
 
242		.matches = {
243			DMI_MATCH(DMI_SYS_VENDOR, "Dell Computer Corporation"),
244			DMI_MATCH(DMI_PRODUCT_NAME, "PowerEdge 1300/"),
245		},
246	},
247	{	/* Handle problems with rebooting on Dell 300's */
248		.callback = set_bios_reboot,
249		.ident = "Dell PowerEdge 300",
250		.matches = {
251			DMI_MATCH(DMI_SYS_VENDOR, "Dell Computer Corporation"),
252			DMI_MATCH(DMI_PRODUCT_NAME, "PowerEdge 300/"),
253		},
254	},
255	{	/* Handle problems with rebooting on Dell Optiplex 745's SFF */
256		.callback = set_bios_reboot,
257		.ident = "Dell OptiPlex 745",
258		.matches = {
259			DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
260			DMI_MATCH(DMI_PRODUCT_NAME, "OptiPlex 745"),
261		},
262	},
263	{	/* Handle problems with rebooting on Dell Optiplex 745's DFF */
264		.callback = set_bios_reboot,
265		.ident = "Dell OptiPlex 745",
266		.matches = {
267			DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
268			DMI_MATCH(DMI_PRODUCT_NAME, "OptiPlex 745"),
269			DMI_MATCH(DMI_BOARD_NAME, "0MM599"),
270		},
271	},
272	{	/* Handle problems with rebooting on Dell Optiplex 745 with 0KW626 */
 
 
273		.callback = set_bios_reboot,
274		.ident = "Dell OptiPlex 745",
275		.matches = {
276			DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
277			DMI_MATCH(DMI_PRODUCT_NAME, "OptiPlex 745"),
278			DMI_MATCH(DMI_BOARD_NAME, "0KW626"),
279		},
280	},
281	{	/* Handle problems with rebooting on Dell Optiplex 330 with 0KP561 */
 
 
 
 
 
 
 
 
 
 
 
 
282		.callback = set_bios_reboot,
283		.ident = "Dell OptiPlex 330",
284		.matches = {
285			DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
286			DMI_MATCH(DMI_PRODUCT_NAME, "OptiPlex 330"),
287			DMI_MATCH(DMI_BOARD_NAME, "0KP561"),
288		},
289	},
290	{	/* Handle problems with rebooting on Dell Optiplex 360 with 0T656F */
291		.callback = set_bios_reboot,
292		.ident = "Dell OptiPlex 360",
293		.matches = {
294			DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
295			DMI_MATCH(DMI_PRODUCT_NAME, "OptiPlex 360"),
296			DMI_MATCH(DMI_BOARD_NAME, "0T656F"),
297		},
298	},
299	{	/* Handle problems with rebooting on Dell OptiPlex 760 with 0G919G */
300		.callback = set_bios_reboot,
301		.ident = "Dell OptiPlex 760",
302		.matches = {
303			DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
304			DMI_MATCH(DMI_PRODUCT_NAME, "OptiPlex 760"),
305			DMI_MATCH(DMI_BOARD_NAME, "0G919G"),
306		},
307	},
308	{	/* Handle problems with rebooting on Dell 2400's */
309		.callback = set_bios_reboot,
310		.ident = "Dell PowerEdge 2400",
311		.matches = {
312			DMI_MATCH(DMI_SYS_VENDOR, "Dell Computer Corporation"),
313			DMI_MATCH(DMI_PRODUCT_NAME, "PowerEdge 2400"),
314		},
315	},
316	{	/* Handle problems with rebooting on Dell T5400's */
317		.callback = set_bios_reboot,
318		.ident = "Dell Precision T5400",
319		.matches = {
320			DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
321			DMI_MATCH(DMI_PRODUCT_NAME, "Precision WorkStation T5400"),
322		},
323	},
324	{	/* Handle problems with rebooting on Dell T7400's */
325		.callback = set_bios_reboot,
326		.ident = "Dell Precision T7400",
327		.matches = {
328			DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
329			DMI_MATCH(DMI_PRODUCT_NAME, "Precision WorkStation T7400"),
330		},
331	},
332	{	/* Handle problems with rebooting on HP laptops */
333		.callback = set_bios_reboot,
334		.ident = "HP Compaq Laptop",
335		.matches = {
336			DMI_MATCH(DMI_SYS_VENDOR, "Hewlett-Packard"),
337			DMI_MATCH(DMI_PRODUCT_NAME, "HP Compaq"),
 
338		},
339	},
340	{	/* Handle problems with rebooting on Dell XPS710 */
341		.callback = set_bios_reboot,
342		.ident = "Dell XPS710",
343		.matches = {
344			DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
345			DMI_MATCH(DMI_PRODUCT_NAME, "Dell XPS710"),
 
346		},
347	},
348	{	/* Handle problems with rebooting on Dell DXP061 */
349		.callback = set_bios_reboot,
350		.ident = "Dell DXP061",
351		.matches = {
352			DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
353			DMI_MATCH(DMI_PRODUCT_NAME, "Dell DXP061"),
354		},
355	},
356	{	/* Handle problems with rebooting on Sony VGN-Z540N */
357		.callback = set_bios_reboot,
358		.ident = "Sony VGN-Z540N",
359		.matches = {
360			DMI_MATCH(DMI_SYS_VENDOR, "Sony Corporation"),
361			DMI_MATCH(DMI_PRODUCT_NAME, "VGN-Z540N"),
 
362		},
363	},
364	{	/* Handle problems with rebooting on CompuLab SBC-FITPC2 */
365		.callback = set_bios_reboot,
366		.ident = "CompuLab SBC-FITPC2",
367		.matches = {
368			DMI_MATCH(DMI_SYS_VENDOR, "CompuLab"),
369			DMI_MATCH(DMI_PRODUCT_NAME, "SBC-FITPC2"),
 
370		},
371	},
372	{	/* Handle problems with rebooting on ASUS P4S800 */
373		.callback = set_bios_reboot,
374		.ident = "ASUS P4S800",
375		.matches = {
376			DMI_MATCH(DMI_BOARD_VENDOR, "ASUSTeK Computer INC."),
377			DMI_MATCH(DMI_BOARD_NAME, "P4S800"),
 
378		},
379	},
380#endif /* CONFIG_X86_32 */
381
382	{	/* Handle reboot issue on Acer Aspire one */
383		.callback = set_kbd_reboot,
384		.ident = "Acer Aspire One A110",
385		.matches = {
386			DMI_MATCH(DMI_SYS_VENDOR, "Acer"),
387			DMI_MATCH(DMI_PRODUCT_NAME, "AOA110"),
388		},
389	},
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	{	/* Handle problems with rebooting on the OptiPlex 990. */
447		.callback = set_pci_reboot,
448		.ident = "Dell OptiPlex 990",
449		.matches = {
450			DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
451			DMI_MATCH(DMI_PRODUCT_NAME, "OptiPlex 990"),
452		},
453	},
454	{	/* Handle problems with rebooting on the Precision M6600. */
455		.callback = set_pci_reboot,
456		.ident = "Dell OptiPlex 990",
 
 
457		.matches = {
458			DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
459			DMI_MATCH(DMI_PRODUCT_NAME, "Precision M6600"),
 
 
 
 
 
 
 
 
 
 
460		},
461	},
 
462	{ }
463};
464
465static int __init reboot_init(void)
466{
467	/*
468	 * Only do the DMI check if reboot_type hasn't been overridden
469	 * on the command line
470	 */
471	if (reboot_default)
472		dmi_check_system(reboot_dmi_table);
473	return 0;
474}
475core_initcall(reboot_init);
476
477static inline void kb_wait(void)
478{
479	int i;
480
481	for (i = 0; i < 0x10000; i++) {
482		if ((inb(0x64) & 0x02) == 0)
483			break;
484		udelay(2);
485	}
486}
487
488static void vmxoff_nmi(int cpu, struct pt_regs *regs)
489{
490	cpu_emergency_vmxoff();
491}
492
493/* Use NMIs as IPIs to tell all CPUs to disable virtualization */
494static void emergency_vmx_disable_all(void)
495{
496	/* Just make sure we won't change CPUs while doing this */
497	local_irq_disable();
498
499	/*
500	 * We need to disable VMX on all CPUs before rebooting, otherwise
501	 * we risk hanging up the machine, because the CPU ignore INIT
502	 * signals when VMX is enabled.
503	 *
504	 * We can't take any locks and we may be on an inconsistent
505	 * state, so we use NMIs as IPIs to tell the other CPUs to disable
506	 * VMX and halt.
507	 *
508	 * For safety, we will avoid running the nmi_shootdown_cpus()
509	 * stuff unnecessarily, but we don't have a way to check
510	 * if other CPUs have VMX enabled. So we will call it only if the
511	 * CPU we are running on has VMX enabled.
512	 *
513	 * We will miss cases where VMX is not enabled on all CPUs. This
514	 * shouldn't do much harm because KVM always enable VMX on all
515	 * CPUs anyway. But we can miss it on the small window where KVM
516	 * is still enabling VMX.
517	 */
518	if (cpu_has_vmx() && cpu_vmx_enabled()) {
519		/* Disable VMX on this CPU. */
520		cpu_vmxoff();
521
522		/* Halt and disable VMX on the other CPUs */
523		nmi_shootdown_cpus(vmxoff_nmi);
524
525	}
526}
527
528
529void __attribute__((weak)) mach_reboot_fixups(void)
530{
531}
532
533/*
534 * Windows compatible x86 hardware expects the following on reboot:
 
535 *
536 * 1) If the FADT has the ACPI reboot register flag set, try it
537 * 2) If still alive, write to the keyboard controller
538 * 3) If still alive, write to the ACPI reboot register again
539 * 4) If still alive, write to the keyboard controller again
 
 
540 *
541 * If the machine is still alive at this stage, it gives up. We default to
542 * following the same pattern, except that if we're still alive after (4) we'll
543 * try to force a triple fault and then cycle between hitting the keyboard
544 * controller and doing that
 
 
 
545 */
546static void native_machine_emergency_restart(void)
547{
548	int i;
549	int attempt = 0;
550	int orig_reboot_type = reboot_type;
 
551
552	if (reboot_emergency)
553		emergency_vmx_disable_all();
554
555	tboot_shutdown(TB_SHUTDOWN_REBOOT);
556
557	/* Tell the BIOS if we want cold or warm reboot */
558	*((unsigned short *)__va(0x472)) = reboot_mode;
 
559
560	for (;;) {
561		/* Could also try the reset bit in the Hammer NB */
562		switch (reboot_type) {
 
 
 
 
 
563		case BOOT_KBD:
564			mach_reboot_fixups(); /* For board specific fixups */
565
566			for (i = 0; i < 10; i++) {
567				kb_wait();
568				udelay(50);
569				outb(0xfe, 0x64); /* Pulse reset low */
570				udelay(50);
571			}
572			if (attempt == 0 && orig_reboot_type == BOOT_ACPI) {
573				attempt = 1;
574				reboot_type = BOOT_ACPI;
575			} else {
576				reboot_type = BOOT_TRIPLE;
577			}
578			break;
579
580		case BOOT_TRIPLE:
581			load_idt(&no_idt);
582			__asm__ __volatile__("int3");
583
584			reboot_type = BOOT_KBD;
 
 
585			break;
586
587#ifdef CONFIG_X86_32
588		case BOOT_BIOS:
589			machine_real_restart(MRR_BIOS);
590
591			reboot_type = BOOT_KBD;
592			break;
593#endif
594
595		case BOOT_ACPI:
596			acpi_reboot();
597			reboot_type = BOOT_KBD;
598			break;
599
600		case BOOT_EFI:
601			if (efi_enabled)
602				efi.reset_system(reboot_mode ?
603						 EFI_RESET_WARM :
604						 EFI_RESET_COLD,
605						 EFI_SUCCESS, 0, NULL);
606			reboot_type = BOOT_KBD;
607			break;
608
609		case BOOT_CF9:
610			port_cf9_safe = true;
611			/* Fall through */
612
613		case BOOT_CF9_COND:
614			if (port_cf9_safe) {
615				u8 cf9 = inb(0xcf9) & ~6;
 
616				outb(cf9|2, 0xcf9); /* Request hard reset */
617				udelay(50);
618				outb(cf9|6, 0xcf9); /* Actually do the reset */
 
619				udelay(50);
620			}
 
 
 
 
 
 
 
 
621			reboot_type = BOOT_KBD;
622			break;
623		}
624	}
625}
626
627void native_machine_shutdown(void)
628{
629	/* Stop the cpus and apics */
630#ifdef CONFIG_SMP
631
632	/* The boot cpu is always logical cpu 0 */
633	int reboot_cpu_id = 0;
634
635#ifdef CONFIG_X86_32
636	/* See if there has been given a command line override */
637	if ((reboot_cpu != -1) && (reboot_cpu < nr_cpu_ids) &&
638		cpu_online(reboot_cpu))
639		reboot_cpu_id = reboot_cpu;
 
 
 
640#endif
641
642	/* Make certain the cpu I'm about to reboot on is online */
643	if (!cpu_online(reboot_cpu_id))
644		reboot_cpu_id = smp_processor_id();
645
646	/* Make certain I only run on the appropriate processor */
647	set_cpus_allowed_ptr(current, cpumask_of(reboot_cpu_id));
648
649	/*
650	 * O.K Now that I'm on the appropriate processor, stop all of the
651	 * others. Also disable the local irq to not receive the per-cpu
652	 * timer interrupt which may trigger scheduler's load balance.
653	 */
654	local_irq_disable();
655	stop_other_cpus();
656#endif
657
658	lapic_shutdown();
659
660#ifdef CONFIG_X86_IO_APIC
661	disable_IO_APIC();
662#endif
663
664#ifdef CONFIG_HPET_TIMER
665	hpet_disable();
666#endif
667
668#ifdef CONFIG_X86_64
669	x86_platform.iommu_shutdown();
670#endif
671}
672
673static void __machine_emergency_restart(int emergency)
674{
675	reboot_emergency = emergency;
676	machine_ops.emergency_restart();
677}
678
679static void native_machine_restart(char *__unused)
680{
681	printk("machine restart\n");
682
683	if (!reboot_force)
684		machine_shutdown();
685	__machine_emergency_restart(0);
686}
687
688static void native_machine_halt(void)
689{
690	/* Stop other cpus and apics */
691	machine_shutdown();
692
693	tboot_shutdown(TB_SHUTDOWN_HALT);
694
695	stop_this_cpu(NULL);
696}
697
698static void native_machine_power_off(void)
699{
700	if (pm_power_off) {
701		if (!reboot_force)
702			machine_shutdown();
703		pm_power_off();
704	}
705	/* A fallback in case there is no PM info available */
706	tboot_shutdown(TB_SHUTDOWN_HALT);
707}
708
709struct machine_ops machine_ops = {
710	.power_off = native_machine_power_off,
711	.shutdown = native_machine_shutdown,
712	.emergency_restart = native_machine_emergency_restart,
713	.restart = native_machine_restart,
714	.halt = native_machine_halt,
715#ifdef CONFIG_KEXEC
716	.crash_shutdown = native_machine_crash_shutdown,
717#endif
718};
719
720void machine_power_off(void)
721{
722	machine_ops.power_off();
723}
724
725void machine_shutdown(void)
726{
727	machine_ops.shutdown();
728}
729
730void machine_emergency_restart(void)
731{
732	__machine_emergency_restart(1);
733}
734
735void machine_restart(char *cmd)
736{
737	machine_ops.restart(cmd);
738}
739
740void machine_halt(void)
741{
742	machine_ops.halt();
743}
744
745#ifdef CONFIG_KEXEC
746void machine_crash_shutdown(struct pt_regs *regs)
747{
748	machine_ops.crash_shutdown(regs);
749}
750#endif
751
752
753#if defined(CONFIG_SMP)
754
755/* This keeps a track of which one is crashing cpu. */
756static int crashing_cpu;
757static nmi_shootdown_cb shootdown_callback;
758
759static atomic_t waiting_for_crash_ipi;
760
761static int crash_nmi_callback(unsigned int val, struct pt_regs *regs)
762{
763	int cpu;
764
765	cpu = raw_smp_processor_id();
766
767	/*
768	 * Don't do anything if this handler is invoked on crashing cpu.
769	 * Otherwise, system will completely hang. Crashing cpu can get
770	 * an NMI if system was initially booted with nmi_watchdog parameter.
771	 */
772	if (cpu == crashing_cpu)
773		return NMI_HANDLED;
774	local_irq_disable();
775
776	shootdown_callback(cpu, regs);
777
778	atomic_dec(&waiting_for_crash_ipi);
779	/* Assume hlt works */
780	halt();
781	for (;;)
782		cpu_relax();
783
784	return NMI_HANDLED;
785}
786
787static void smp_send_nmi_allbutself(void)
788{
789	apic->send_IPI_allbutself(NMI_VECTOR);
790}
791
792/*
793 * Halt all other CPUs, calling the specified function on each of them
794 *
795 * This function can be used to halt all other CPUs on crash
796 * or emergency reboot time. The function passed as parameter
797 * will be called inside a NMI handler on all CPUs.
798 */
799void nmi_shootdown_cpus(nmi_shootdown_cb callback)
800{
801	unsigned long msecs;
802	local_irq_disable();
803
804	/* Make a note of crashing cpu. Will be used in NMI callback. */
805	crashing_cpu = safe_smp_processor_id();
806
807	shootdown_callback = callback;
808
809	atomic_set(&waiting_for_crash_ipi, num_online_cpus() - 1);
810	/* Would it be better to replace the trap vector here? */
811	if (register_nmi_handler(NMI_LOCAL, crash_nmi_callback,
812				 NMI_FLAG_FIRST, "crash"))
813		return;		/* Return what? */
814	/*
815	 * Ensure the new callback function is set before sending
816	 * out the NMI
817	 */
818	wmb();
819
820	smp_send_nmi_allbutself();
821
822	msecs = 1000; /* Wait at most a second for the other cpus to stop */
823	while ((atomic_read(&waiting_for_crash_ipi) > 0) && msecs) {
824		mdelay(1);
825		msecs--;
826	}
827
828	/* Leave the nmi callback set */
829}
830#else /* !CONFIG_SMP */
831void nmi_shootdown_cpus(nmi_shootdown_cb callback)
832{
833	/* No other CPUs to shoot down */
834}
835#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