ACPI hibernate: Introduce new kernel parameter acpi_sleep=s4_nonvs
[linux-2.6/mini2440.git] / arch / x86 / kernel / acpi / sleep.c
blob707c1f6f95faedfb7db7aed696c45c79461b0ea2
1 /*
2 * sleep.c - x86-specific ACPI sleep support.
4 * Copyright (C) 2001-2003 Patrick Mochel
5 * Copyright (C) 2001-2003 Pavel Machek <pavel@suse.cz>
6 */
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>
15 #include "realmode/wakeup.h"
16 #include "sleep.h"
18 unsigned long acpi_wakeup_address;
19 unsigned long acpi_realmode_flags;
21 /* address in low memory of the wakeup routine. */
22 static unsigned long acpi_realmode;
24 #if defined(CONFIG_SMP) && defined(CONFIG_64BIT)
25 static char temp_stack[4096];
26 #endif
28 /**
29 * acpi_save_state_mem - save kernel state
31 * Create an identity mapped page table and copy the wakeup routine to
32 * low memory.
34 * Note that this is too late to change acpi_wakeup_address.
36 int acpi_save_state_mem(void)
38 struct wakeup_header *header;
40 if (!acpi_realmode) {
41 printk(KERN_ERR "Could not allocate memory during boot, "
42 "S3 disabled\n");
43 return -ENOMEM;
45 memcpy((void *)acpi_realmode, &wakeup_code_start, WAKEUP_SIZE);
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;
53 header->video_mode = saved_video_mode;
55 header->wakeup_jmp_seg = acpi_wakeup_address >> 4;
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.
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);
78 #ifndef CONFIG_64BIT
79 store_gdt((struct desc_ptr *)&header->pmode_gdt);
81 header->pmode_efer_low = nx_enabled;
82 if (header->pmode_efer_low & 1) {
83 /* This is strange, why not save efer, always? */
84 rdmsr(MSR_EFER, header->pmode_efer_low,
85 header->pmode_efer_high);
87 #endif /* !CONFIG_64BIT */
89 header->pmode_cr0 = read_cr0();
90 header->pmode_cr4 = read_cr4_safe();
91 header->realmode_flags = acpi_realmode_flags;
92 header->real_magic = 0x12345678;
94 #ifndef CONFIG_64BIT
95 header->pmode_entry = (u32)&wakeup_pmode_return;
96 header->pmode_cr3 = (u32)(swsusp_pg_dir - __PAGE_OFFSET);
97 saved_magic = 0x12345678;
98 #else /* CONFIG_64BIT */
99 header->trampoline_segment = setup_trampoline() >> 4;
100 #ifdef CONFIG_SMP
101 stack_start.sp = temp_stack + sizeof(temp_stack);
102 early_gdt_descr.address =
103 (unsigned long)get_cpu_gdt_table(smp_processor_id());
104 #endif
105 initial_code = (unsigned long)wakeup_long64;
106 saved_magic = 0x123456789abcdef0;
107 #endif /* CONFIG_64BIT */
109 return 0;
113 * acpi_restore_state - undo effects of acpi_save_state_mem
115 void acpi_restore_state_mem(void)
121 * acpi_reserve_bootmem - do _very_ early ACPI initialisation
123 * We allocate a page from the first 1MB of memory for the wakeup
124 * routine for when we come back from a sleep state. The
125 * runtime allocator allows specification of <16MB pages, but not
126 * <1MB pages.
128 void __init acpi_reserve_bootmem(void)
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;
136 acpi_realmode = (unsigned long)alloc_bootmem_low(WAKEUP_SIZE);
138 if (!acpi_realmode) {
139 printk(KERN_ERR "ACPI: Cannot allocate lowmem, S3 disabled.\n");
140 return;
143 acpi_wakeup_address = virt_to_phys((void *)acpi_realmode);
147 static int __init acpi_sleep_setup(char *str)
149 while ((str != NULL) && (*str != '\0')) {
150 if (strncmp(str, "s3_bios", 7) == 0)
151 acpi_realmode_flags |= 1;
152 if (strncmp(str, "s3_mode", 7) == 0)
153 acpi_realmode_flags |= 2;
154 if (strncmp(str, "s3_beep", 7) == 0)
155 acpi_realmode_flags |= 4;
156 #ifdef CONFIG_HIBERNATION
157 if (strncmp(str, "s4_nohwsig", 10) == 0)
158 acpi_no_s4_hw_signature();
159 #endif
160 if (strncmp(str, "old_ordering", 12) == 0)
161 acpi_old_suspend_ordering();
162 if (strncmp(str, "s4_nonvs", 8) == 0)
163 acpi_s4_no_nvs();
164 str = strchr(str, ',');
165 if (str != NULL)
166 str += strspn(str, ", \t");
168 return 1;
171 __setup("acpi_sleep=", acpi_sleep_setup);