arch/i386/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 <asm/smp.h>
  12 #include <asm/tlbflush.h>
  13
  14 /* address in low memory of the wakeup routine. */
  15 unsigned long acpi_wakeup_address = 0;
  16 unsigned long acpi_video_flags;
  17 extern char wakeup_start, wakeup_end;
  18
  19 extern void zap_low_mappings(void);
  20
  21 extern unsigned long FASTCALL(acpi_copy_wakeup_routine(unsigned long));
  22
  23 static void init_low_mapping(pgd_t *pgd, int pgd_limit)
  24 {
  25         int pgd_ofs = 0;
  26
  27         while ((pgd_ofs < pgd_limit) && (pgd_ofs + USER_PTRS_PER_PGD < PTRS_PER_PGD)) {
  28                 set_pgd(pgd, *(pgd+USER_PTRS_PER_PGD));
  29                 pgd_ofs++, pgd++;
  30         }
  31         flush_tlb_all();
  32 }
  33
  34 /**
  35  * acpi_save_state_mem - save kernel state
  36  *
  37  * Create an identity mapped page table and copy the wakeup routine to
  38  * low memory.
  39  */
  40 int acpi_save_state_mem (void)
  41 {
  42         if (!acpi_wakeup_address)
  43                 return 1;
  44         init_low_mapping(swapper_pg_dir, USER_PTRS_PER_PGD);
  45         memcpy((void *) acpi_wakeup_address, &wakeup_start, &wakeup_end - &wakeup_start);
  46         acpi_copy_wakeup_routine(acpi_wakeup_address);
  47
  48         return 0;
  49 }
  50
  51 /*
  52  * acpi_restore_state - undo effects of acpi_save_state_mem
  53  */
  54 void acpi_restore_state_mem (void)
  55 {
  56         zap_low_mappings();
  57 }
  58
  59 /**
  60  * acpi_reserve_bootmem - do _very_ early ACPI initialisation
  61  *
  62  * We allocate a page from the first 1MB of memory for the wakeup
  63  * routine for when we come back from a sleep state. The
  64  * runtime allocator allows specification of <16MB pages, but not
  65  * <1MB pages.
  66  */
  67 void __init acpi_reserve_bootmem(void)
  68 {
  69         if ((&wakeup_end - &wakeup_start) > PAGE_SIZE) {
  70                 printk(KERN_ERR "ACPI: Wakeup code way too big, S3 disabled.\n");
  71                 return;
  72         }
  73
  74         acpi_wakeup_address = (unsigned long)alloc_bootmem_low(PAGE_SIZE);
  75         if (!acpi_wakeup_address)
  76                 printk(KERN_ERR "ACPI: Cannot allocate lowmem, S3 disabled.\n");
  77 }
  78
  79 static int __init acpi_sleep_setup(char *str)
  80 {
  81         while ((str != NULL) && (*str != '\0')) {
  82                 if (strncmp(str, "s3_bios", 7) == 0)
  83                         acpi_video_flags = 1;
  84                 if (strncmp(str, "s3_mode", 7) == 0)
  85                         acpi_video_flags |= 2;
  86                 str = strchr(str, ',');
  87                 if (str != NULL)
  88                         str += strspn(str, ", \t");
  89         }
  90         return 1;
  91 }
  92
  93
  94 __setup("acpi_sleep=", acpi_sleep_setup);
  95
  96
  97 static __init int reset_videomode_after_s3(struct dmi_system_id *d)
  98 {
  99         acpi_video_flags |= 2;
 100         return 0;
 101 }
 102
 103 static __initdata struct dmi_system_id acpisleep_dmi_table[] = {
 104         {       /* Reset video mode after returning from ACPI S3 sleep */
 105                 .callback = reset_videomode_after_s3,
 106                 .ident = "Toshiba Satellite 4030cdt",
 107                 .matches = {
 108                         DMI_MATCH(DMI_PRODUCT_NAME, "S4030CDT/4.3"),
 109                 },
 110         },
 111         { }
 112 };
 113
 114 static int __init acpisleep_dmi_init(void)
 115 {
 116         dmi_check_system(acpisleep_dmi_table);
 117         return 0;
 118 }
 119
 120 core_initcall(acpisleep_dmi_init);