xref: /linux/arch/x86/kernel/acpi/sleep.c (revision cddc0ab71194a09c0ac359be10a0f1ef976ddc95)
1 /*
2  * sleep.c - x86-specific ACPI sleep support.
3  *
4  *  Copyright (C) 2001-2003 Patrick Mochel
5  *  Copyright (C) 2001-2003 Pavel Machek <pavel@suse.cz>
6  */
7 
8 #include <linux/acpi.h>
9 #include <linux/bootmem.h>
10 #include <linux/dmi.h>
11 #include <linux/cpumask.h>
12 
13 #include "realmode/wakeup.h"
14 #include "sleep.h"
15 
16 unsigned long acpi_wakeup_address;
17 unsigned long acpi_realmode_flags;
18 
19 /* address in low memory of the wakeup routine. */
20 static unsigned long acpi_realmode;
21 
22 #ifdef CONFIG_64BIT
23 static char temp_stack[10240];
24 #endif
25 
26 /**
27  * acpi_save_state_mem - save kernel state
28  *
29  * Create an identity mapped page table and copy the wakeup routine to
30  * low memory.
31  *
32  * Note that this is too late to change acpi_wakeup_address.
33  */
34 int acpi_save_state_mem(void)
35 {
36 	struct wakeup_header *header;
37 
38 	if (!acpi_realmode) {
39 		printk(KERN_ERR "Could not allocate memory during boot, "
40 		       "S3 disabled\n");
41 		return -ENOMEM;
42 	}
43 	memcpy((void *)acpi_realmode, &wakeup_code_start, WAKEUP_SIZE);
44 
45 	header = (struct wakeup_header *)(acpi_realmode + HEADER_OFFSET);
46 	if (header->signature != 0x51ee1111) {
47 		printk(KERN_ERR "wakeup header does not match\n");
48 		return -EINVAL;
49 	}
50 
51 	header->video_mode = saved_video_mode;
52 
53 #ifndef CONFIG_64BIT
54 	store_gdt((struct desc_ptr *)&header->pmode_gdt);
55 
56 	header->pmode_efer_low = nx_enabled;
57 	if (header->pmode_efer_low & 1) {
58 		/* This is strange, why not save efer, always? */
59 		rdmsr(MSR_EFER, header->pmode_efer_low,
60 			header->pmode_efer_high);
61 	}
62 #endif /* !CONFIG_64BIT */
63 
64 	header->pmode_cr0 = read_cr0();
65 	header->pmode_cr4 = read_cr4();
66 	header->realmode_flags = acpi_realmode_flags;
67 	header->real_magic = 0x12345678;
68 
69 #ifndef CONFIG_64BIT
70 	header->pmode_entry = (u32)&wakeup_pmode_return;
71 	header->pmode_cr3 = (u32)(swsusp_pg_dir - __PAGE_OFFSET);
72 	saved_magic = 0x12345678;
73 #else /* CONFIG_64BIT */
74 	header->trampoline_segment = setup_trampoline() >> 4;
75 	init_rsp = (unsigned long)temp_stack + 4096;
76 	initial_code = (unsigned long)wakeup_long64;
77 	saved_magic = 0x123456789abcdef0;
78 #endif /* CONFIG_64BIT */
79 
80 	return 0;
81 }
82 
83 /*
84  * acpi_restore_state - undo effects of acpi_save_state_mem
85  */
86 void acpi_restore_state_mem(void)
87 {
88 }
89 
90 
91 /**
92  * acpi_reserve_bootmem - do _very_ early ACPI initialisation
93  *
94  * We allocate a page from the first 1MB of memory for the wakeup
95  * routine for when we come back from a sleep state. The
96  * runtime allocator allows specification of <16MB pages, but not
97  * <1MB pages.
98  */
99 void __init acpi_reserve_bootmem(void)
100 {
101 	if ((&wakeup_code_end - &wakeup_code_start) > WAKEUP_SIZE) {
102 		printk(KERN_ERR
103 		       "ACPI: Wakeup code way too big, S3 disabled.\n");
104 		return;
105 	}
106 
107 	acpi_realmode = (unsigned long)alloc_bootmem_low(WAKEUP_SIZE);
108 
109 	if (!acpi_realmode) {
110 		printk(KERN_ERR "ACPI: Cannot allocate lowmem, S3 disabled.\n");
111 		return;
112 	}
113 
114 	acpi_wakeup_address = acpi_realmode;
115 }
116 
117 
118 static int __init acpi_sleep_setup(char *str)
119 {
120 	while ((str != NULL) && (*str != '\0')) {
121 		if (strncmp(str, "s3_bios", 7) == 0)
122 			acpi_realmode_flags |= 1;
123 		if (strncmp(str, "s3_mode", 7) == 0)
124 			acpi_realmode_flags |= 2;
125 		if (strncmp(str, "s3_beep", 7) == 0)
126 			acpi_realmode_flags |= 4;
127 		str = strchr(str, ',');
128 		if (str != NULL)
129 			str += strspn(str, ", \t");
130 	}
131 	return 1;
132 }
133 
134 __setup("acpi_sleep=", acpi_sleep_setup);
135