x86, sleep: Always save the value of EFER
[linux-3.10.git] / arch / x86 / kernel / acpi / sleep.c
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 #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                         acpi_s4_no_nvs();
162 #endif
163                 if (strncmp(str, "old_ordering", 12) == 0)
164                         acpi_old_suspend_ordering();
165                 str = strchr(str, ',');
166                 if (str != NULL)
167                         str += strspn(str, ", \t");
168         }
169         return 1;
170 }
171
172 __setup("acpi_sleep=", acpi_sleep_setup);