[deliverable/linux.git] / arch / i386 / kernel / reboot.c

/*
 *  linux/arch/i386/kernel/reboot.c
 */

#include <linux/mm.h>
#include <linux/module.h>
#include <linux/delay.h>
#include <linux/init.h>
#include <linux/interrupt.h>
#include <linux/mc146818rtc.h>
#include <linux/efi.h>
#include <linux/dmi.h>
#include <linux/ctype.h>
#include <linux/pm.h>
#include <asm/uaccess.h>
#include <asm/apic.h>
#include <asm/desc.h>
#include "mach_reboot.h"
#include <linux/reboot_fixups.h>

/*
 * Power off function, if any
 */
void (*pm_power_off)(void);
EXPORT_SYMBOL(pm_power_off);

static int reboot_mode;
static int reboot_thru_bios;

#ifdef CONFIG_SMP
static int reboot_cpu = -1;
#endif
static int __init reboot_setup(char *str)
{
	while(1) {
		switch (*str) {
		case 'w': /* "warm" reboot (no memory testing etc) */
			reboot_mode = 0x1234;
			break;
		case 'c': /* "cold" reboot (with memory testing etc) */
			reboot_mode = 0x0;
			break;
		case 'b': /* "bios" reboot by jumping through the BIOS */
			reboot_thru_bios = 1;
			break;
		case 'h': /* "hard" reboot by toggling RESET and/or crashing the CPU */
			reboot_thru_bios = 0;
			break;
#ifdef CONFIG_SMP
		case 's': /* "smp" reboot by executing reset on BSP or other CPU*/
			if (isdigit(*(str+1))) {
				reboot_cpu = (int) (*(str+1) - '0');
				if (isdigit(*(str+2)))
					reboot_cpu = reboot_cpu*10 + (int)(*(str+2) - '0');
			}
				/* we will leave sorting out the final value 
				when we are ready to reboot, since we might not
 				have set up boot_cpu_id or smp_num_cpu */
			break;
#endif
		}
		if((str = strchr(str,',')) != NULL)
			str++;
		else
			break;
	}
	return 1;
}

__setup("reboot=", reboot_setup);

/*
 * Reboot options and system auto-detection code provided by
 * Dell Inc. so their systems "just work". :-)
 */

/*
 * Some machines require the "reboot=b"  commandline option, this quirk makes that automatic.
 */
static int __init set_bios_reboot(struct dmi_system_id *d)
{
	if (!reboot_thru_bios) {
		reboot_thru_bios = 1;
		printk(KERN_INFO "%s series board detected. Selecting BIOS-method for reboots.\n", d->ident);
	}
	return 0;
}

static struct dmi_system_id __initdata reboot_dmi_table[] = {
	{	/* Handle problems with rebooting on Dell 1300's */
		.callback = set_bios_reboot,
		.ident = "Dell PowerEdge 1300",
		.matches = {
			DMI_MATCH(DMI_SYS_VENDOR, "Dell Computer Corporation"),
			DMI_MATCH(DMI_PRODUCT_NAME, "PowerEdge 1300/"),
		},
	},
	{	/* Handle problems with rebooting on Dell 300's */
		.callback = set_bios_reboot,
		.ident = "Dell PowerEdge 300",
		.matches = {
			DMI_MATCH(DMI_SYS_VENDOR, "Dell Computer Corporation"),
			DMI_MATCH(DMI_PRODUCT_NAME, "PowerEdge 300/"),
		},
	},
	{	/* Handle problems with rebooting on Dell 2400's */
		.callback = set_bios_reboot,
		.ident = "Dell PowerEdge 2400",
		.matches = {
			DMI_MATCH(DMI_SYS_VENDOR, "Dell Computer Corporation"),
			DMI_MATCH(DMI_PRODUCT_NAME, "PowerEdge 2400"),
		},
	},
	{	/* Handle problems with rebooting on HP laptops */
		.callback = set_bios_reboot,
		.ident = "HP Compaq Laptop",
		.matches = {
			DMI_MATCH(DMI_SYS_VENDOR, "Hewlett-Packard"),
			DMI_MATCH(DMI_PRODUCT_NAME, "HP Compaq"),
		},
	},
	{ }
};

static int __init reboot_init(void)
{
	dmi_check_system(reboot_dmi_table);
	return 0;
}

core_initcall(reboot_init);

/* The following code and data reboots the machine by switching to real
   mode and jumping to the BIOS reset entry point, as if the CPU has
   really been reset.  The previous version asked the keyboard
   controller to pulse the CPU reset line, which is more thorough, but
   doesn't work with at least one type of 486 motherboard.  It is easy
   to stop this code working; hence the copious comments. */

static unsigned long long
real_mode_gdt_entries [3] =
{
	0x0000000000000000ULL,	/* Null descriptor */
	0x00009a000000ffffULL,	/* 16-bit real-mode 64k code at 0x00000000 */
	0x000092000100ffffULL	/* 16-bit real-mode 64k data at 0x00000100 */
};

static struct Xgt_desc_struct
real_mode_gdt = { sizeof (real_mode_gdt_entries) - 1, (long)real_mode_gdt_entries },
real_mode_idt = { 0x3ff, 0 },
no_idt = { 0, 0 };


/* This is 16-bit protected mode code to disable paging and the cache,
   switch to real mode and jump to the BIOS reset code.

   The instruction that switches to real mode by writing to CR0 must be
   followed immediately by a far jump instruction, which set CS to a
   valid value for real mode, and flushes the prefetch queue to avoid
   running instructions that have already been decoded in protected
   mode.

   Clears all the flags except ET, especially PG (paging), PE
   (protected-mode enable) and TS (task switch for coprocessor state
   save).  Flushes the TLB after paging has been disabled.  Sets CD and
   NW, to disable the cache on a 486, and invalidates the cache.  This
   is more like the state of a 486 after reset.  I don't know if
   something else should be done for other chips.

   More could be done here to set up the registers as if a CPU reset had
   occurred; hopefully real BIOSs don't assume much. */

static unsigned char real_mode_switch [] =
{
	0x66, 0x0f, 0x20, 0xc0,			/*    movl  %cr0,%eax        */
	0x66, 0x83, 0xe0, 0x11,			/*    andl  $0x00000011,%eax */
	0x66, 0x0d, 0x00, 0x00, 0x00, 0x60,	/*    orl   $0x60000000,%eax */
	0x66, 0x0f, 0x22, 0xc0,			/*    movl  %eax,%cr0        */
	0x66, 0x0f, 0x22, 0xd8,			/*    movl  %eax,%cr3        */
	0x66, 0x0f, 0x20, 0xc3,			/*    movl  %cr0,%ebx        */
	0x66, 0x81, 0xe3, 0x00, 0x00, 0x00, 0x60,	/*    andl  $0x60000000,%ebx */
	0x74, 0x02,				/*    jz    f                */
	0x0f, 0x09,				/*    wbinvd                 */
	0x24, 0x10,				/* f: andb  $0x10,al         */
	0x66, 0x0f, 0x22, 0xc0			/*    movl  %eax,%cr0        */
};
static unsigned char jump_to_bios [] =
{
	0xea, 0x00, 0x00, 0xff, 0xff		/*    ljmp  $0xffff,$0x0000  */
};

/*
 * Switch to real mode and then execute the code
 * specified by the code and length parameters.
 * We assume that length will aways be less that 100!
 */
void machine_real_restart(unsigned char *code, int length)
{
	unsigned long flags;

	local_irq_disable();

	/* Write zero to CMOS register number 0x0f, which the BIOS POST
	   routine will recognize as telling it to do a proper reboot.  (Well
	   that's what this book in front of me says -- it may only apply to
	   the Phoenix BIOS though, it's not clear).  At the same time,
	   disable NMIs by setting the top bit in the CMOS address register,
	   as we're about to do peculiar things to the CPU.  I'm not sure if
	   `outb_p' is needed instead of just `outb'.  Use it to be on the
	   safe side.  (Yes, CMOS_WRITE does outb_p's. -  Paul G.)
	 */

	spin_lock_irqsave(&rtc_lock, flags);
	CMOS_WRITE(0x00, 0x8f);
	spin_unlock_irqrestore(&rtc_lock, flags);

	/* Remap the kernel at virtual address zero, as well as offset zero
	   from the kernel segment.  This assumes the kernel segment starts at
	   virtual address PAGE_OFFSET. */

	memcpy (swapper_pg_dir, swapper_pg_dir + USER_PGD_PTRS,
		sizeof (swapper_pg_dir [0]) * KERNEL_PGD_PTRS);

	/*
	 * Use `swapper_pg_dir' as our page directory.
	 */
	load_cr3(swapper_pg_dir);

	/* Write 0x1234 to absolute memory location 0x472.  The BIOS reads
	   this on booting to tell it to "Bypass memory test (also warm
	   boot)".  This seems like a fairly standard thing that gets set by
	   REBOOT.COM programs, and the previous reset routine did this
	   too. */

	*((unsigned short *)0x472) = reboot_mode;

	/* For the switch to real mode, copy some code to low memory.  It has
	   to be in the first 64k because it is running in 16-bit mode, and it
	   has to have the same physical and virtual address, because it turns
	   off paging.  Copy it near the end of the first page, out of the way
	   of BIOS variables. */

	memcpy ((void *) (0x1000 - sizeof (real_mode_switch) - 100),
		real_mode_switch, sizeof (real_mode_switch));
	memcpy ((void *) (0x1000 - 100), code, length);

	/* Set up the IDT for real mode. */

	load_idt(&real_mode_idt);

	/* Set up a GDT from which we can load segment descriptors for real
	   mode.  The GDT is not used in real mode; it is just needed here to
	   prepare the descriptors. */

	load_gdt(&real_mode_gdt);

	/* Load the data segment registers, and thus the descriptors ready for
	   real mode.  The base address of each segment is 0x100, 16 times the
	   selector value being loaded here.  This is so that the segment
	   registers don't have to be reloaded after switching to real mode:
	   the values are consistent for real mode operation already. */

	__asm__ __volatile__ ("movl $0x0010,%%eax\n"
				"\tmovl %%eax,%%ds\n"
				"\tmovl %%eax,%%es\n"
				"\tmovl %%eax,%%fs\n"
				"\tmovl %%eax,%%gs\n"
				"\tmovl %%eax,%%ss" : : : "eax");

	/* Jump to the 16-bit code that we copied earlier.  It disables paging
	   and the cache, switches to real mode, and jumps to the BIOS reset
	   entry point. */

	__asm__ __volatile__ ("ljmp $0x0008,%0"
				:
				: "i" ((void *) (0x1000 - sizeof (real_mode_switch) - 100)));
}
#ifdef CONFIG_APM_MODULE
EXPORT_SYMBOL(machine_real_restart);
#endif

void machine_shutdown(void)
{
#ifdef CONFIG_SMP
	int reboot_cpu_id;

	/* The boot cpu is always logical cpu 0 */
	reboot_cpu_id = 0;

	/* See if there has been given a command line override */
	if ((reboot_cpu != -1) && (reboot_cpu < NR_CPUS) &&
		cpu_isset(reboot_cpu, cpu_online_map)) {
		reboot_cpu_id = reboot_cpu;
	}

	/* Make certain the cpu I'm rebooting on is online */
	if (!cpu_isset(reboot_cpu_id, cpu_online_map)) {
		reboot_cpu_id = smp_processor_id();
	}

	/* Make certain I only run on the appropriate processor */
	set_cpus_allowed(current, cpumask_of_cpu(reboot_cpu_id));

	/* O.K. Now that I'm on the appropriate processor, stop
	 * all of the others, and disable their local APICs.
	 */

	smp_send_stop();
#endif /* CONFIG_SMP */

	lapic_shutdown();

#ifdef CONFIG_X86_IO_APIC
	disable_IO_APIC();
#endif
}

void machine_emergency_restart(void)
{
	if (!reboot_thru_bios) {
		if (efi_enabled) {
			efi.reset_system(EFI_RESET_COLD, EFI_SUCCESS, 0, NULL);
			load_idt(&no_idt);
			__asm__ __volatile__("int3");
		}
		/* rebooting needs to touch the page at absolute addr 0 */
		*((unsigned short *)__va(0x472)) = reboot_mode;
		for (;;) {
			mach_reboot_fixups(); /* for board specific fixups */
			mach_reboot();
			/* That didn't work - force a triple fault.. */
			load_idt(&no_idt);
			__asm__ __volatile__("int3");
		}
	}
	if (efi_enabled)
		efi.reset_system(EFI_RESET_WARM, EFI_SUCCESS, 0, NULL);

	machine_real_restart(jump_to_bios, sizeof(jump_to_bios));
}

void machine_restart(char * __unused)
{
	machine_shutdown();
	machine_emergency_restart();
}

void machine_halt(void)
{
}

void machine_power_off(void)
{
	if (pm_power_off) {
		machine_shutdown();
		pm_power_off();
	}
}
Commit	Line	Data
1da177e4 LT	1	/*
	2	* linux/arch/i386/kernel/reboot.c
	3	*/
	4
	5	#include <linux/mm.h>
	6	#include <linux/module.h>
	7	#include <linux/delay.h>
	8	#include <linux/init.h>
	9	#include <linux/interrupt.h>
	10	#include <linux/mc146818rtc.h>
	11	#include <linux/efi.h>
	12	#include <linux/dmi.h>
6f673d83	13	#include <linux/ctype.h>
6e3fbee5	14	#include <linux/pm.h>
1da177e4 LT	15	#include <asm/uaccess.h>
1da177e4 LT	16	#include <asm/apic.h>
4d37e7e3	17	#include <asm/desc.h>
1da177e4	18	#include "mach_reboot.h"
a2f7c354	19	#include <linux/reboot_fixups.h>
1da177e4 LT	20
	21	/*
	22	* Power off function, if any
	23	*/
	24	void (*pm_power_off)(void);
129f6946	25	EXPORT_SYMBOL(pm_power_off);
1da177e4 LT	26
	27	static int reboot_mode;
	28	static int reboot_thru_bios;
	29
	30	#ifdef CONFIG_SMP
1da177e4	31	static int reboot_cpu = -1;
1da177e4 LT	32	#endif
	33	static int __init reboot_setup(char *str)
	34	{
	35	while(1) {
	36	switch (*str) {
	37	case 'w': /* "warm" reboot (no memory testing etc) */
	38	reboot_mode = 0x1234;
	39	break;
	40	case 'c': /* "cold" reboot (with memory testing etc) */
	41	reboot_mode = 0x0;
	42	break;
	43	case 'b': /* "bios" reboot by jumping through the BIOS */
	44	reboot_thru_bios = 1;
	45	break;
	46	case 'h': /* "hard" reboot by toggling RESET and/or crashing the CPU */
	47	reboot_thru_bios = 0;
	48	break;
	49	#ifdef CONFIG_SMP
	50	case 's': /* "smp" reboot by executing reset on BSP or other CPU*/
6f673d83	51	if (isdigit(*(str+1))) {
1da177e4	52	reboot_cpu = (int) (*(str+1) - '0');
6f673d83	53	if (isdigit(*(str+2)))
1da177e4 LT	54	reboot_cpu = reboot_cpu10 + (int)((str+2) - '0');
	55	}
	56	/* we will leave sorting out the final value
	57	when we are ready to reboot, since we might not
	58	have set up boot_cpu_id or smp_num_cpu */
	59	break;
	60	#endif
	61	}
	62	if((str = strchr(str,',')) != NULL)
	63	str++;
	64	else
	65	break;
	66	}
	67	return 1;
	68	}
	69
	70	__setup("reboot=", reboot_setup);
	71
	72	/*
	73	* Reboot options and system auto-detection code provided by
	74	* Dell Inc. so their systems "just work". :-)
	75	*/
	76
	77	/*
	78	* Some machines require the "reboot=b" commandline option, this quirk makes that automatic.
	79	*/
	80	static int __init set_bios_reboot(struct dmi_system_id *d)
	81	{
	82	if (!reboot_thru_bios) {
	83	reboot_thru_bios = 1;
	84	printk(KERN_INFO "%s series board detected. Selecting BIOS-method for reboots.\n", d->ident);
	85	}
	86	return 0;
	87	}
	88
1da177e4 LT	89	static struct dmi_system_id __initdata reboot_dmi_table[] = {
1da177e4 LT	90	{ /* Handle problems with rebooting on Dell 1300's */
dd2a1305	91	.callback = set_bios_reboot,
1da177e4 LT	92	.ident = "Dell PowerEdge 1300",
	93	.matches = {
	94	DMI_MATCH(DMI_SYS_VENDOR, "Dell Computer Corporation"),
	95	DMI_MATCH(DMI_PRODUCT_NAME, "PowerEdge 1300/"),
	96	},
	97	},
	98	{ /* Handle problems with rebooting on Dell 300's */
	99	.callback = set_bios_reboot,
	100	.ident = "Dell PowerEdge 300",
	101	.matches = {
	102	DMI_MATCH(DMI_SYS_VENDOR, "Dell Computer Corporation"),
	103	DMI_MATCH(DMI_PRODUCT_NAME, "PowerEdge 300/"),
	104	},
	105	},
	106	{ /* Handle problems with rebooting on Dell 2400's */
	107	.callback = set_bios_reboot,
	108	.ident = "Dell PowerEdge 2400",
	109	.matches = {
	110	DMI_MATCH(DMI_SYS_VENDOR, "Dell Computer Corporation"),
	111	DMI_MATCH(DMI_PRODUCT_NAME, "PowerEdge 2400"),
	112	},
	113	},
766c3f94	114	{ /* Handle problems with rebooting on HP laptops */
d91b14c4	115	.callback = set_bios_reboot,
766c3f94	116	.ident = "HP Compaq Laptop",
d91b14c4 TV	117	.matches = {
d91b14c4 TV	118	DMI_MATCH(DMI_SYS_VENDOR, "Hewlett-Packard"),
766c3f94	119	DMI_MATCH(DMI_PRODUCT_NAME, "HP Compaq"),
d91b14c4 TV	120	},
d91b14c4 TV	121	},
1da177e4 LT	122	{ }
	123	};
	124
	125	static int __init reboot_init(void)
	126	{
	127	dmi_check_system(reboot_dmi_table);
	128	return 0;
	129	}
	130
	131	core_initcall(reboot_init);
	132
	133	/* The following code and data reboots the machine by switching to real
	134	mode and jumping to the BIOS reset entry point, as if the CPU has
	135	really been reset. The previous version asked the keyboard
	136	controller to pulse the CPU reset line, which is more thorough, but
	137	doesn't work with at least one type of 486 motherboard. It is easy
	138	to stop this code working; hence the copious comments. */
	139
	140	static unsigned long long
	141	real_mode_gdt_entries [3] =
	142	{
	143	0x0000000000000000ULL, /* Null descriptor */
	144	0x00009a000000ffffULL, /* 16-bit real-mode 64k code at 0x00000000 */
	145	0x000092000100ffffULL /* 16-bit real-mode 64k data at 0x00000100 */
	146	};
	147
05f4a3ec RR	148	static struct Xgt_desc_struct
	149	real_mode_gdt = { sizeof (real_mode_gdt_entries) - 1, (long)real_mode_gdt_entries },
	150	real_mode_idt = { 0x3ff, 0 },
	151	no_idt = { 0, 0 };
1da177e4 LT	152
	153
	154	/* This is 16-bit protected mode code to disable paging and the cache,
	155	switch to real mode and jump to the BIOS reset code.
	156
	157	The instruction that switches to real mode by writing to CR0 must be
	158	followed immediately by a far jump instruction, which set CS to a
	159	valid value for real mode, and flushes the prefetch queue to avoid
	160	running instructions that have already been decoded in protected
	161	mode.
	162
	163	Clears all the flags except ET, especially PG (paging), PE
	164	(protected-mode enable) and TS (task switch for coprocessor state
	165	save). Flushes the TLB after paging has been disabled. Sets CD and
	166	NW, to disable the cache on a 486, and invalidates the cache. This
	167	is more like the state of a 486 after reset. I don't know if
	168	something else should be done for other chips.
	169
	170	More could be done here to set up the registers as if a CPU reset had
	171	occurred; hopefully real BIOSs don't assume much. */
	172
	173	static unsigned char real_mode_switch [] =
	174	{
	175	0x66, 0x0f, 0x20, 0xc0, /* movl %cr0,%eax */
	176	0x66, 0x83, 0xe0, 0x11, /* andl $0x00000011,%eax */
	177	0x66, 0x0d, 0x00, 0x00, 0x00, 0x60, /* orl $0x60000000,%eax */
	178	0x66, 0x0f, 0x22, 0xc0, /* movl %eax,%cr0 */
	179	0x66, 0x0f, 0x22, 0xd8, /* movl %eax,%cr3 */
	180	0x66, 0x0f, 0x20, 0xc3, /* movl %cr0,%ebx */
	181	0x66, 0x81, 0xe3, 0x00, 0x00, 0x00, 0x60, /* andl $0x60000000,%ebx */
	182	0x74, 0x02, /* jz f */
	183	0x0f, 0x09, /* wbinvd */
	184	0x24, 0x10, /* f: andb $0x10,al */
	185	0x66, 0x0f, 0x22, 0xc0 /* movl %eax,%cr0 */
	186	};
	187	static unsigned char jump_to_bios [] =
	188	{
	189	0xea, 0x00, 0x00, 0xff, 0xff /* ljmp $0xffff,$0x0000 */
	190	};
	191
	192	/*
	193	* Switch to real mode and then execute the code
	194	* specified by the code and length parameters.
	195	* We assume that length will aways be less that 100!
	196	*/
	197	void machine_real_restart(unsigned char *code, int length)
	198	{
	199	unsigned long flags;
	200
	201	local_irq_disable();
	202
	203	/* Write zero to CMOS register number 0x0f, which the BIOS POST
	204	routine will recognize as telling it to do a proper reboot. (Well
	205	that's what this book in front of me says -- it may only apply to
	206	the Phoenix BIOS though, it's not clear). At the same time,
	207	disable NMIs by setting the top bit in the CMOS address register,
	208	as we're about to do peculiar things to the CPU. I'm not sure if
	209	`outb_p' is needed instead of just `outb'. Use it to be on the
	210	safe side. (Yes, CMOS_WRITE does outb_p's. - Paul G.)
	211	*/
	212
	213	spin_lock_irqsave(&rtc_lock, flags);
	214	CMOS_WRITE(0x00, 0x8f);
	215	spin_unlock_irqrestore(&rtc_lock, flags);
216
217	/* Remap the kernel at virtual address zero, as well as offset zero
218	from the kernel segment. This assumes the kernel segment starts at
219	virtual address PAGE_OFFSET. */
220
221	memcpy (swapper_pg_dir, swapper_pg_dir + USER_PGD_PTRS,
222	sizeof (swapper_pg_dir [0]) * KERNEL_PGD_PTRS);
223
224	/*
225	* Use `swapper_pg_dir' as our page directory.
226	*/
227	load_cr3(swapper_pg_dir);
228
229	/* Write 0x1234 to absolute memory location 0x472. The BIOS reads
230	this on booting to tell it to "Bypass memory test (also warm
231	boot)". This seems like a fairly standard thing that gets set by
232	REBOOT.COM programs, and the previous reset routine did this
233	too. */
234
235	((unsigned short )0x472) = reboot_mode;
236
237	/* For the switch to real mode, copy some code to low memory. It has
238	to be in the first 64k because it is running in 16-bit mode, and it
239	has to have the same physical and virtual address, because it turns
240	off paging. Copy it near the end of the first page, out of the way
241	of BIOS variables. */
242
243	memcpy ((void *) (0x1000 - sizeof (real_mode_switch) - 100),
244	real_mode_switch, sizeof (real_mode_switch));
245	memcpy ((void *) (0x1000 - 100), code, length);
246
247	/* Set up the IDT for real mode. */
248
4d37e7e3	249	load_idt(&real_mode_idt);
1da177e4 LT	250
	251	/* Set up a GDT from which we can load segment descriptors for real
	252	mode. The GDT is not used in real mode; it is just needed here to
	253	prepare the descriptors. */
	254
4d37e7e3	255	load_gdt(&real_mode_gdt);
1da177e4 LT	256
	257	/* Load the data segment registers, and thus the descriptors ready for
	258	real mode. The base address of each segment is 0x100, 16 times the
	259	selector value being loaded here. This is so that the segment
	260	registers don't have to be reloaded after switching to real mode:
	261	the values are consistent for real mode operation already. */
	262
	263	__asm__ __volatile__ ("movl $0x0010,%%eax\n"
	264	"\tmovl %%eax,%%ds\n"
	265	"\tmovl %%eax,%%es\n"
	266	"\tmovl %%eax,%%fs\n"
	267	"\tmovl %%eax,%%gs\n"
	268	"\tmovl %%eax,%%ss" : : : "eax");
	269
	270	/* Jump to the 16-bit code that we copied earlier. It disables paging
	271	and the cache, switches to real mode, and jumps to the BIOS reset
	272	entry point. */
	273
	274	__asm__ __volatile__ ("ljmp $0x0008,%0"
	275	:
	276	: "i" ((void *) (0x1000 - sizeof (real_mode_switch) - 100)));
	277	}
129f6946 AD	278	#ifdef CONFIG_APM_MODULE
	279	EXPORT_SYMBOL(machine_real_restart);
	280	#endif
1da177e4	281
dd2a1305	282	void machine_shutdown(void)
1da177e4 LT	283	{
1da177e4 LT	284	#ifdef CONFIG_SMP
dd2a1305 EB	285	int reboot_cpu_id;
	286
	287	/* The boot cpu is always logical cpu 0 */
	288	reboot_cpu_id = 0;
	289
	290	/* See if there has been given a command line override */
d8e392e7	291	if ((reboot_cpu != -1) && (reboot_cpu < NR_CPUS) &&
dd2a1305 EB	292	cpu_isset(reboot_cpu, cpu_online_map)) {
dd2a1305 EB	293	reboot_cpu_id = reboot_cpu;
1da177e4 LT	294	}
1da177e4 LT	295
dd2a1305 EB	296	/* Make certain the cpu I'm rebooting on is online */
	297	if (!cpu_isset(reboot_cpu_id, cpu_online_map)) {
	298	reboot_cpu_id = smp_processor_id();
1da177e4	299	}
dd2a1305 EB	300
	301	/* Make certain I only run on the appropriate processor */
	302	set_cpus_allowed(current, cpumask_of_cpu(reboot_cpu_id));
	303
	304	/* O.K. Now that I'm on the appropriate processor, stop
	305	* all of the others, and disable their local APICs.
1da177e4	306	*/
dd2a1305	307
1da177e4 LT	308	smp_send_stop();
	309	#endif /* CONFIG_SMP */
	310
	311	lapic_shutdown();
	312
	313	#ifdef CONFIG_X86_IO_APIC
	314	disable_IO_APIC();
	315	#endif
dd2a1305 EB	316	}
dd2a1305 EB	317
4a1421f8	318	void machine_emergency_restart(void)
dd2a1305	319	{
1da177e4 LT	320	if (!reboot_thru_bios) {
	321	if (efi_enabled) {
	322	efi.reset_system(EFI_RESET_COLD, EFI_SUCCESS, 0, NULL);
4d37e7e3	323	load_idt(&no_idt);
1da177e4 LT	324	__asm__ __volatile__("int3");
	325	}
	326	/* rebooting needs to touch the page at absolute addr 0 */
	327	((unsigned short )__va(0x472)) = reboot_mode;
	328	for (;;) {
a2f7c354	329	mach_reboot_fixups(); /* for board specific fixups */
1da177e4 LT	330	mach_reboot();
1da177e4 LT	331	/* That didn't work - force a triple fault.. */
4d37e7e3	332	load_idt(&no_idt);
1da177e4 LT	333	__asm__ __volatile__("int3");
	334	}
	335	}
	336	if (efi_enabled)
	337	efi.reset_system(EFI_RESET_WARM, EFI_SUCCESS, 0, NULL);
	338
	339	machine_real_restart(jump_to_bios, sizeof(jump_to_bios));
	340	}
	341
4a1421f8 EB	342	void machine_restart(char * __unused)
	343	{
	344	machine_shutdown();
	345	machine_emergency_restart();
	346	}
	347
1da177e4 LT	348	void machine_halt(void)
	349	{
	350	}
	351
1da177e4 LT	352	void machine_power_off(void)
1da177e4 LT	353	{
6e3fbee5 EB	354	if (pm_power_off) {
6e3fbee5 EB	355	machine_shutdown();
1da177e4	356	pm_power_off();
6e3fbee5	357	}
1da177e4 LT	358	}
1da177e4 LT	359
1da177e4	360