xref: /linux/arch/x86/kernel/acpi/sleep.c (revision 092e0e7e520a1fca03e13c9f2d157432a8657ff2)
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/memblock.h>
11 #include <linux/dmi.h>
12 #include <linux/cpumask.h>
13 #include <asm/segment.h>
14 #include <asm/desc.h>
15 
16 #include "realmode/wakeup.h"
17 #include "sleep.h"
18 
19 unsigned long acpi_wakeup_address;
20 unsigned long acpi_realmode_flags;
21 
22 /* address in low memory of the wakeup routine. */
23 static unsigned long acpi_realmode;
24 
25 #if defined(CONFIG_SMP) && defined(CONFIG_64BIT)
26 static char temp_stack[4096];
27 #endif
28 
29 /**
30  * acpi_save_state_mem - save kernel state
31  *
32  * Create an identity mapped page table and copy the wakeup routine to
33  * low memory.
34  *
35  * Note that this is too late to change acpi_wakeup_address.
36  */
37 int acpi_save_state_mem(void)
38 {
39 	struct wakeup_header *header;
40 
41 	if (!acpi_realmode) {
42 		printk(KERN_ERR "Could not allocate memory during boot, "
43 		       "S3 disabled\n");
44 		return -ENOMEM;
45 	}
46 	memcpy((void *)acpi_realmode, &wakeup_code_start, WAKEUP_SIZE);
47 
48 	header = (struct wakeup_header *)(acpi_realmode + HEADER_OFFSET);
49 	if (header->signature != 0x51ee1111) {
50 		printk(KERN_ERR "wakeup header does not match\n");
51 		return -EINVAL;
52 	}
53 
54 	header->video_mode = saved_video_mode;
55 
56 	header->wakeup_jmp_seg = acpi_wakeup_address >> 4;
57 
58 	/*
59 	 * Set up the wakeup GDT.  We set these up as Big Real Mode,
60 	 * that is, with limits set to 4 GB.  At least the Lenovo
61 	 * Thinkpad X61 is known to need this for the video BIOS
62 	 * initialization quirk to work; this is likely to also
63 	 * be the case for other laptops or integrated video devices.
64 	 */
65 
66 	/* GDT[0]: GDT self-pointer */
67 	header->wakeup_gdt[0] =
68 		(u64)(sizeof(header->wakeup_gdt) - 1) +
69 		((u64)(acpi_wakeup_address +
70 			((char *)&header->wakeup_gdt - (char *)acpi_realmode))
71 				<< 16);
72 	/* GDT[1]: big real mode-like code segment */
73 	header->wakeup_gdt[1] =
74 		GDT_ENTRY(0x809b, acpi_wakeup_address, 0xfffff);
75 	/* GDT[2]: big real mode-like data segment */
76 	header->wakeup_gdt[2] =
77 		GDT_ENTRY(0x8093, acpi_wakeup_address, 0xfffff);
78 
79 #ifndef CONFIG_64BIT
80 	store_gdt((struct desc_ptr *)&header->pmode_gdt);
81 
82 	if (rdmsr_safe(MSR_EFER, &header->pmode_efer_low,
83 		       &header->pmode_efer_high))
84 		header->pmode_efer_low = header->pmode_efer_high = 0;
85 #endif /* !CONFIG_64BIT */
86 
87 	header->pmode_cr0 = read_cr0();
88 	header->pmode_cr4 = read_cr4_safe();
89 	header->realmode_flags = acpi_realmode_flags;
90 	header->real_magic = 0x12345678;
91 
92 #ifndef CONFIG_64BIT
93 	header->pmode_entry = (u32)&wakeup_pmode_return;
94 	header->pmode_cr3 = (u32)(swsusp_pg_dir - __PAGE_OFFSET);
95 	saved_magic = 0x12345678;
96 #else /* CONFIG_64BIT */
97 	header->trampoline_segment = setup_trampoline() >> 4;
98 #ifdef CONFIG_SMP
99 	stack_start.sp = temp_stack + sizeof(temp_stack);
100 	early_gdt_descr.address =
101 			(unsigned long)get_cpu_gdt_table(smp_processor_id());
102 	initial_gs = per_cpu_offset(smp_processor_id());
103 #endif
104 	initial_code = (unsigned long)wakeup_long64;
105        saved_magic = 0x123456789abcdef0L;
106 #endif /* CONFIG_64BIT */
107 
108 	return 0;
109 }
110 
111 /*
112  * acpi_restore_state - undo effects of acpi_save_state_mem
113  */
114 void acpi_restore_state_mem(void)
115 {
116 }
117 
118 
119 /**
120  * acpi_reserve_wakeup_memory - do _very_ early ACPI initialisation
121  *
122  * We allocate a page from the first 1MB of memory for the wakeup
123  * routine for when we come back from a sleep state. The
124  * runtime allocator allows specification of <16MB pages, but not
125  * <1MB pages.
126  */
127 void __init acpi_reserve_wakeup_memory(void)
128 {
129 	phys_addr_t mem;
130 
131 	if ((&wakeup_code_end - &wakeup_code_start) > WAKEUP_SIZE) {
132 		printk(KERN_ERR
133 		       "ACPI: Wakeup code way too big, S3 disabled.\n");
134 		return;
135 	}
136 
137 	mem = memblock_find_in_range(0, 1<<20, WAKEUP_SIZE, PAGE_SIZE);
138 
139 	if (mem == MEMBLOCK_ERROR) {
140 		printk(KERN_ERR "ACPI: Cannot allocate lowmem, S3 disabled.\n");
141 		return;
142 	}
143 	acpi_realmode = (unsigned long) phys_to_virt(mem);
144 	acpi_wakeup_address = mem;
145 	memblock_x86_reserve_range(mem, mem + WAKEUP_SIZE, "ACPI WAKEUP");
146 }
147 
148 
149 static int __init acpi_sleep_setup(char *str)
150 {
151 	while ((str != NULL) && (*str != '\0')) {
152 		if (strncmp(str, "s3_bios", 7) == 0)
153 			acpi_realmode_flags |= 1;
154 		if (strncmp(str, "s3_mode", 7) == 0)
155 			acpi_realmode_flags |= 2;
156 		if (strncmp(str, "s3_beep", 7) == 0)
157 			acpi_realmode_flags |= 4;
158 #ifdef CONFIG_HIBERNATION
159 		if (strncmp(str, "s4_nohwsig", 10) == 0)
160 			acpi_no_s4_hw_signature();
161 		if (strncmp(str, "s4_nonvs", 8) == 0) {
162 			pr_warning("ACPI: acpi_sleep=s4_nonvs is deprecated, "
163 					"please use acpi_sleep=nonvs instead");
164 			acpi_nvs_nosave();
165 		}
166 #endif
167 		if (strncmp(str, "nonvs", 5) == 0)
168 			acpi_nvs_nosave();
169 		if (strncmp(str, "old_ordering", 12) == 0)
170 			acpi_old_suspend_ordering();
171 		str = strchr(str, ',');
172 		if (str != NULL)
173 			str += strspn(str, ", \t");
174 	}
175 	return 1;
176 }
177 
178 __setup("acpi_sleep=", acpi_sleep_setup);
179