xref: /linux/arch/x86/kernel/acpi/sleep.c (revision d39d0ed196aa1685bb24771e92f78633c66ac9cb)
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@ucw.cz>
6  */
7 
8 #include <linux/acpi.h>
9 #include <linux/bootmem.h>
10 #include <linux/dmi.h>
11 #include <linux/cpumask.h>
12 #include <asm/segment.h>
13 #include <asm/desc.h>
14 
15 #include "realmode/wakeup.h"
16 #include "sleep.h"
17 
18 unsigned long acpi_wakeup_address;
19 unsigned long acpi_realmode_flags;
20 
21 /* address in low memory of the wakeup routine. */
22 static unsigned long acpi_realmode;
23 
24 #if defined(CONFIG_SMP) && defined(CONFIG_64BIT)
25 static char temp_stack[4096];
26 #endif
27 
28 /**
29  * acpi_save_state_mem - save kernel state
30  *
31  * Create an identity mapped page table and copy the wakeup routine to
32  * low memory.
33  *
34  * Note that this is too late to change acpi_wakeup_address.
35  */
36 int acpi_save_state_mem(void)
37 {
38 	struct wakeup_header *header;
39 
40 	if (!acpi_realmode) {
41 		printk(KERN_ERR "Could not allocate memory during boot, "
42 		       "S3 disabled\n");
43 		return -ENOMEM;
44 	}
45 	memcpy((void *)acpi_realmode, &wakeup_code_start, WAKEUP_SIZE);
46 
47 	header = (struct wakeup_header *)(acpi_realmode + HEADER_OFFSET);
48 	if (header->signature != 0x51ee1111) {
49 		printk(KERN_ERR "wakeup header does not match\n");
50 		return -EINVAL;
51 	}
52 
53 	header->video_mode = saved_video_mode;
54 
55 	header->wakeup_jmp_seg = acpi_wakeup_address >> 4;
56 
57 	/*
58 	 * Set up the wakeup GDT.  We set these up as Big Real Mode,
59 	 * that is, with limits set to 4 GB.  At least the Lenovo
60 	 * Thinkpad X61 is known to need this for the video BIOS
61 	 * initialization quirk to work; this is likely to also
62 	 * be the case for other laptops or integrated video devices.
63 	 */
64 
65 	/* GDT[0]: GDT self-pointer */
66 	header->wakeup_gdt[0] =
67 		(u64)(sizeof(header->wakeup_gdt) - 1) +
68 		((u64)(acpi_wakeup_address +
69 			((char *)&header->wakeup_gdt - (char *)acpi_realmode))
70 				<< 16);
71 	/* GDT[1]: big real mode-like code segment */
72 	header->wakeup_gdt[1] =
73 		GDT_ENTRY(0x809b, acpi_wakeup_address, 0xfffff);
74 	/* GDT[2]: big real mode-like data segment */
75 	header->wakeup_gdt[2] =
76 		GDT_ENTRY(0x8093, acpi_wakeup_address, 0xfffff);
77 
78 #ifndef CONFIG_64BIT
79 	store_gdt((struct desc_ptr *)&header->pmode_gdt);
80 
81 	if (rdmsr_safe(MSR_EFER, &header->pmode_efer_low,
82 		       &header->pmode_efer_high))
83 		header->pmode_efer_low = header->pmode_efer_high = 0;
84 #endif /* !CONFIG_64BIT */
85 
86 	header->pmode_cr0 = read_cr0();
87 	header->pmode_cr4 = read_cr4_safe();
88 	header->realmode_flags = acpi_realmode_flags;
89 	header->real_magic = 0x12345678;
90 
91 #ifndef CONFIG_64BIT
92 	header->pmode_entry = (u32)&wakeup_pmode_return;
93 	header->pmode_cr3 = (u32)(swsusp_pg_dir - __PAGE_OFFSET);
94 	saved_magic = 0x12345678;
95 #else /* CONFIG_64BIT */
96 	header->trampoline_segment = setup_trampoline() >> 4;
97 #ifdef CONFIG_SMP
98 	stack_start.sp = temp_stack + sizeof(temp_stack);
99 	early_gdt_descr.address =
100 			(unsigned long)get_cpu_gdt_table(smp_processor_id());
101 	initial_gs = per_cpu_offset(smp_processor_id());
102 #endif
103 	initial_code = (unsigned long)wakeup_long64;
104        saved_magic = 0x123456789abcdef0L;
105 #endif /* CONFIG_64BIT */
106 
107 	return 0;
108 }
109 
110 /*
111  * acpi_restore_state - undo effects of acpi_save_state_mem
112  */
113 void acpi_restore_state_mem(void)
114 {
115 }
116 
117 
118 /**
119  * acpi_reserve_wakeup_memory - do _very_ early ACPI initialisation
120  *
121  * We allocate a page from the first 1MB of memory for the wakeup
122  * routine for when we come back from a sleep state. The
123  * runtime allocator allows specification of <16MB pages, but not
124  * <1MB pages.
125  */
126 void __init acpi_reserve_wakeup_memory(void)
127 {
128 	unsigned long mem;
129 
130 	if ((&wakeup_code_end - &wakeup_code_start) > WAKEUP_SIZE) {
131 		printk(KERN_ERR
132 		       "ACPI: Wakeup code way too big, S3 disabled.\n");
133 		return;
134 	}
135 
136 	mem = find_e820_area(0, 1<<20, WAKEUP_SIZE, PAGE_SIZE);
137 
138 	if (mem == -1L) {
139 		printk(KERN_ERR "ACPI: Cannot allocate lowmem, S3 disabled.\n");
140 		return;
141 	}
142 	acpi_realmode = (unsigned long) phys_to_virt(mem);
143 	acpi_wakeup_address = mem;
144 	reserve_early(mem, mem + WAKEUP_SIZE, "ACPI WAKEUP");
145 }
146 
147 
148 static int __init acpi_sleep_setup(char *str)
149 {
150 	while ((str != NULL) && (*str != '\0')) {
151 		if (strncmp(str, "s3_bios", 7) == 0)
152 			acpi_realmode_flags |= 1;
153 		if (strncmp(str, "s3_mode", 7) == 0)
154 			acpi_realmode_flags |= 2;
155 		if (strncmp(str, "s3_beep", 7) == 0)
156 			acpi_realmode_flags |= 4;
157 #ifdef CONFIG_HIBERNATION
158 		if (strncmp(str, "s4_nohwsig", 10) == 0)
159 			acpi_no_s4_hw_signature();
160 		if (strncmp(str, "s4_nonvs", 8) == 0) {
161 			pr_warning("ACPI: acpi_sleep=s4_nonvs is deprecated, "
162 					"please use acpi_sleep=nonvs instead");
163 			acpi_nvs_nosave();
164 		}
165 #endif
166 		if (strncmp(str, "nonvs", 5) == 0)
167 			acpi_nvs_nosave();
168 		if (strncmp(str, "old_ordering", 12) == 0)
169 			acpi_old_suspend_ordering();
170 		str = strchr(str, ',');
171 		if (str != NULL)
172 			str += strspn(str, ", \t");
173 	}
174 	return 1;
175 }
176 
177 __setup("acpi_sleep=", acpi_sleep_setup);
178