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