aboutsummaryrefslogtreecommitdiffstats
path: root/arch/x86/kernel/acpi/sleep.c
blob: 36af01f029eddbfe7b2bdc05a0f2b59ab5c3666a (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
/*
 * sleep.c - x86-specific ACPI sleep support.
 *
 *  Copyright (C) 2001-2003 Patrick Mochel
 *  Copyright (C) 2001-2003 Pavel Machek <pavel@suse.cz>
 */

#include <linux/acpi.h>
#include <linux/bootmem.h>
#include <linux/dmi.h>
#include <linux/cpumask.h>

#include "realmode/wakeup.h"
#include "sleep.h"

unsigned long acpi_wakeup_address;
unsigned long acpi_realmode_flags;

/* address in low memory of the wakeup routine. */
static unsigned long acpi_realmode;

#ifdef CONFIG_64BIT
static char temp_stack[10240];
#endif

/**
 * acpi_save_state_mem - save kernel state
 *
 * Create an identity mapped page table and copy the wakeup routine to
 * low memory.
 *
 * Note that this is too late to change acpi_wakeup_address.
 */
int acpi_save_state_mem(void)
{
	struct wakeup_header *header;

	if (!acpi_realmode) {
		printk(KERN_ERR "Could not allocate memory during boot, "
		       "S3 disabled\n");
		return -ENOMEM;
	}
	memcpy((void *)acpi_realmode, &wakeup_code_start, WAKEUP_SIZE);

	header = (struct wakeup_header *)(acpi_realmode + HEADER_OFFSET);
	if (header->signature != 0x51ee1111) {
		printk(KERN_ERR "wakeup header does not match\n");
		return -EINVAL;
	}

	header->video_mode = saved_video_mode;

	header->wakeup_jmp_seg = acpi_wakeup_address >> 4;
	/* GDT[0]: GDT self-pointer */
	header->wakeup_gdt[0] =
		(u64)(sizeof(header->wakeup_gdt) - 1) +
		((u64)(acpi_wakeup_address +
			((char *)&header->wakeup_gdt - (char *)acpi_realmode))
				<< 16);
	/* GDT[1]: real-mode-like code segment */
	header->wakeup_gdt[1] = (0x009bULL << 40) +
		((u64)acpi_wakeup_address << 16) + 0xffff;
	/* GDT[2]: real-mode-like data segment */
	header->wakeup_gdt[2] = (0x0093ULL << 40) +
		((u64)acpi_wakeup_address << 16) + 0xffff;

#ifndef CONFIG_64BIT
	store_gdt((struct desc_ptr *)&header->pmode_gdt);

	header->pmode_efer_low = nx_enabled;
	if (header->pmode_efer_low & 1) {
		/* This is strange, why not save efer, always? */
		rdmsr(MSR_EFER, header->pmode_efer_low,
			header->pmode_efer_high);
	}
#endif /* !CONFIG_64BIT */

	header->pmode_cr0 = read_cr0();
	header->pmode_cr4 = read_cr4();
	header->realmode_flags = acpi_realmode_flags;
	header->real_magic = 0x12345678;

#ifndef CONFIG_64BIT
	header->pmode_entry = (u32)&wakeup_pmode_return;
	header->pmode_cr3 = (u32)(swsusp_pg_dir - __PAGE_OFFSET);
	saved_magic = 0x12345678;
#else /* CONFIG_64BIT */
	header->trampoline_segment = setup_trampoline() >> 4;
	init_rsp = (unsigned long)temp_stack + 4096;
	initial_code = (unsigned long)wakeup_long64;
	saved_magic = 0x123456789abcdef0;
#endif /* CONFIG_64BIT */

	return 0;
}

/*
 * acpi_restore_state - undo effects of acpi_save_state_mem
 */
void acpi_restore_state_mem(void)
{
}


/**
 * acpi_reserve_bootmem - do _very_ early ACPI initialisation
 *
 * We allocate a page from the first 1MB of memory for the wakeup
 * routine for when we come back from a sleep state. The
 * runtime allocator allows specification of <16MB pages, but not
 * <1MB pages.
 */
void __init acpi_reserve_bootmem(void)
{
	if ((&wakeup_code_end - &wakeup_code_start) > WAKEUP_SIZE) {
		printk(KERN_ERR
		       "ACPI: Wakeup code way too big, S3 disabled.\n");
		return;
	}

	acpi_realmode = (unsigned long)alloc_bootmem_low(WAKEUP_SIZE);

	if (!acpi_realmode) {
		printk(KERN_ERR "ACPI: Cannot allocate lowmem, S3 disabled.\n");
		return;
	}

	acpi_wakeup_address = virt_to_phys((void *)acpi_realmode);
}


static int __init acpi_sleep_setup(char *str)
{
	while ((str != NULL) && (*str != '\0')) {
		if (strncmp(str, "s3_bios", 7) == 0)
			acpi_realmode_flags |= 1;
		if (strncmp(str, "s3_mode", 7) == 0)
			acpi_realmode_flags |= 2;
		if (strncmp(str, "s3_beep", 7) == 0)
			acpi_realmode_flags |= 4;
		str = strchr(str, ',');
		if (str != NULL)
			str += strspn(str, ", \t");
	}
	return 1;
}

__setup("acpi_sleep=", acpi_sleep_setup);