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
  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 /* XXX: this macro should move to asm-x86/segment.h and be shared with the
  27    boot code... */
  28 #define GDT_ENTRY(flags, base, limit)           \
  29         (((u64)(base & 0xff000000) << 32) |     \
  30          ((u64)flags << 40) |                   \
  31          ((u64)(limit & 0x00ff0000) << 32) |    \
  32          ((u64)(base & 0x00ffffff) << 16) |     \
  33          ((u64)(limit & 0x0000ffff)))
  34
  35 /**
  36  * acpi_save_state_mem - save kernel state
  37  *
  38  * Create an identity mapped page table and copy the wakeup routine to
  39  * low memory.
  40  *
  41  * Note that this is too late to change acpi_wakeup_address.
  42  */
  43 int acpi_save_state_mem(void)
  44 {
  45         struct wakeup_header *header;
  46
  47         if (!acpi_realmode) {
  48                 printk(KERN_ERR "Could not allocate memory during boot, "
  49                        "S3 disabled\n");
  50                 return -ENOMEM;
  51         }
  52         memcpy((void *)acpi_realmode, &wakeup_code_start, WAKEUP_SIZE);
  53
  54         header = (struct wakeup_header *)(acpi_realmode + HEADER_OFFSET);
  55         if (header->signature != 0x51ee1111) {
  56                 printk(KERN_ERR "wakeup header does not match\n");
  57                 return -EINVAL;
  58         }
  59
  60         header->video_mode = saved_video_mode;
  61
  62         header->wakeup_jmp_seg = acpi_wakeup_address >> 4;
  63         /* GDT[0]: GDT self-pointer */
  64         header->wakeup_gdt[0] =
  65                 (u64)(sizeof(header->wakeup_gdt) - 1) +
  66                 ((u64)(acpi_wakeup_address +
  67                         ((char *)&header->wakeup_gdt - (char *)acpi_realmode))
  68                                 << 16);
  69         /* GDT[1]: real-mode-like code segment */
  70         header->wakeup_gdt[1] =
  71                 GDT_ENTRY(0x809b, acpi_wakeup_address, 0xfffff);
  72         /* GDT[2]: real-mode-like data segment */
  73         header->wakeup_gdt[2] =
  74                 GDT_ENTRY(0x8093, acpi_wakeup_address, 0xfffff);
  75
  76 #ifndef CONFIG_64BIT
  77         store_gdt((struct desc_ptr *)&header->pmode_gdt);
  78
  79         header->pmode_efer_low = nx_enabled;
  80         if (header->pmode_efer_low & 1) {
  81                 /* This is strange, why not save efer, always? */
  82                 rdmsr(MSR_EFER, header->pmode_efer_low,
  83                         header->pmode_efer_high);
  84         }
  85 #endif /* !CONFIG_64BIT */
  86
  87         header->pmode_cr0 = read_cr0();
  88         header->pmode_cr4 = read_cr4();
  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         init_rsp = (unsigned long)temp_stack + 4096;
  99         initial_code = (unsigned long)wakeup_long64;
 100         saved_magic = 0x123456789abcdef0;
 101 #endif /* CONFIG_64BIT */
 102
 103         return 0;
 104 }
 105
 106 /*
 107  * acpi_restore_state - undo effects of acpi_save_state_mem
 108  */
 109 void acpi_restore_state_mem(void)
 110 {
 111 }
 112
 113
 114 /**
 115  * acpi_reserve_bootmem - do _very_ early ACPI initialisation
 116  *
 117  * We allocate a page from the first 1MB of memory for the wakeup
 118  * routine for when we come back from a sleep state. The
 119  * runtime allocator allows specification of <16MB pages, but not
 120  * <1MB pages.
 121  */
 122 void __init acpi_reserve_bootmem(void)
 123 {
 124         if ((&wakeup_code_end - &wakeup_code_start) > WAKEUP_SIZE) {
 125                 printk(KERN_ERR
 126                        "ACPI: Wakeup code way too big, S3 disabled.\n");
 127                 return;
 128         }
 129
 130         acpi_realmode = (unsigned long)alloc_bootmem_low(WAKEUP_SIZE);
 131
 132         if (!acpi_realmode) {
 133                 printk(KERN_ERR "ACPI: Cannot allocate lowmem, S3 disabled.\n");
 134                 return;
 135         }
 136
 137         acpi_wakeup_address = virt_to_phys((void *)acpi_realmode);
 138 }
 139
 140
 141 static int __init acpi_sleep_setup(char *str)
 142 {
 143         while ((str != NULL) && (*str != '\0')) {
 144                 if (strncmp(str, "s3_bios", 7) == 0)
 145                         acpi_realmode_flags |= 1;
 146                 if (strncmp(str, "s3_mode", 7) == 0)
 147                         acpi_realmode_flags |= 2;
 148                 if (strncmp(str, "s3_beep", 7) == 0)
 149                         acpi_realmode_flags |= 4;
 150                 str = strchr(str, ',');
 151                 if (str != NULL)
 152                         str += strspn(str, ", \t");
 153         }
 154         return 1;
 155 }
 156
 157 __setup("acpi_sleep=", acpi_sleep_setup);