kernel/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@ucw.cz>
   6  */
   7
   8 #include <linux/acpi.h>
   9 #include <linux/bootmem.h>
  10 #include <linux/memblock.h>
  11 #include <linux/dmi.h>
  12 #include <linux/cpumask.h>
  13 #include <asm/segment.h>
  14 #include <asm/desc.h>
  15 #include <asm/pgtable.h>
  16 #include <asm/cacheflush.h>
  17 #include <asm/realmode.h>
  18
  19 #include "../../realmode/rm/wakeup.h"
  20 #include "sleep.h"
  21
  22 unsigned long acpi_realmode_flags;
  23
  24 #if defined(CONFIG_SMP) && defined(CONFIG_64BIT)
  25 static char temp_stack[4096];
  26 #endif
  27
  28 /**
  29  * x86_acpi_enter_sleep_state - enter sleep state
  30  * @state: Sleep state to enter.
  31  *
  32  * Wrapper around acpi_enter_sleep_state() to be called by assmebly.
  33  */
  34 acpi_status asmlinkage __visible x86_acpi_enter_sleep_state(u8 state)
  35 {
  36         return acpi_enter_sleep_state(state);
  37 }
  38
  39 /**
  40  * x86_acpi_suspend_lowlevel - save kernel state
  41  *
  42  * Create an identity mapped page table and copy the wakeup routine to
  43  * low memory.
  44  */
  45 int x86_acpi_suspend_lowlevel(void)
  46 {
  47         struct wakeup_header *header =
  48                 (struct wakeup_header *) __va(real_mode_header->wakeup_header);
  49
  50         if (header->signature != WAKEUP_HEADER_SIGNATURE) {
  51                 printk(KERN_ERR "wakeup header does not match\n");
  52                 return -EINVAL;
  53         }
  54
  55         header->video_mode = saved_video_mode;
  56
  57         header->pmode_behavior = 0;
  58
  59 #ifndef CONFIG_64BIT
  60         native_store_gdt((struct desc_ptr *)&header->pmode_gdt);
  61
  62         /*
  63          * We have to check that we can write back the value, and not
  64          * just read it.  At least on 90 nm Pentium M (Family 6, Model
  65          * 13), reading an invalid MSR is not guaranteed to trap, see
  66          * Erratum X4 in "Intel Pentium M Processor on 90 nm Process
  67          * with 2-MB L2 Cache and Intel® Processor A100 and A110 on 90
  68          * nm process with 512-KB L2 Cache Specification Update".
  69          */
  70         if (!rdmsr_safe(MSR_EFER,
  71                         &header->pmode_efer_low,
  72                         &header->pmode_efer_high) &&
  73             !wrmsr_safe(MSR_EFER,
  74                         header->pmode_efer_low,
  75                         header->pmode_efer_high))
  76                 header->pmode_behavior |= (1 << WAKEUP_BEHAVIOR_RESTORE_EFER);
  77 #endif /* !CONFIG_64BIT */
  78
  79         header->pmode_cr0 = read_cr0();
  80         if (__this_cpu_read(cpu_info.cpuid_level) >= 0) {
  81                 header->pmode_cr4 = __read_cr4();
  82                 header->pmode_behavior |= (1 << WAKEUP_BEHAVIOR_RESTORE_CR4);
  83         }
  84         if (!rdmsr_safe(MSR_IA32_MISC_ENABLE,
  85                         &header->pmode_misc_en_low,
  86                         &header->pmode_misc_en_high) &&
  87             !wrmsr_safe(MSR_IA32_MISC_ENABLE,
  88                         header->pmode_misc_en_low,
  89                         header->pmode_misc_en_high))
  90                 header->pmode_behavior |=
  91                         (1 << WAKEUP_BEHAVIOR_RESTORE_MISC_ENABLE);
  92         header->realmode_flags = acpi_realmode_flags;
  93         header->real_magic = 0x12345678;
  94
  95 #ifndef CONFIG_64BIT
  96         header->pmode_entry = (u32)&wakeup_pmode_return;
  97         header->pmode_cr3 = (u32)__pa_symbol(initial_page_table);
  98         saved_magic = 0x12345678;
  99 #else /* CONFIG_64BIT */
 100 #ifdef CONFIG_SMP
 101         stack_start = (unsigned long)temp_stack + sizeof(temp_stack);
 102         early_gdt_descr.address =
 103                         (unsigned long)get_cpu_gdt_table(smp_processor_id());
 104         initial_gs = per_cpu_offset(smp_processor_id());
 105 #endif
 106         initial_code = (unsigned long)wakeup_long64;
 107        saved_magic = 0x123456789abcdef0L;
 108 #endif /* CONFIG_64BIT */
 109
 110         do_suspend_lowlevel();
 111         return 0;
 112 }
 113
 114 static int __init acpi_sleep_setup(char *str)
 115 {
 116         while ((str != NULL) && (*str != '\0')) {
 117                 if (strncmp(str, "s3_bios", 7) == 0)
 118                         acpi_realmode_flags |= 1;
 119                 if (strncmp(str, "s3_mode", 7) == 0)
 120                         acpi_realmode_flags |= 2;
 121                 if (strncmp(str, "s3_beep", 7) == 0)
 122                         acpi_realmode_flags |= 4;
 123 #ifdef CONFIG_HIBERNATION
 124                 if (strncmp(str, "s4_nohwsig", 10) == 0)
 125                         acpi_no_s4_hw_signature();
 126 #endif
 127                 if (strncmp(str, "nonvs", 5) == 0)
 128                         acpi_nvs_nosave();
 129                 if (strncmp(str, "nonvs_s3", 8) == 0)
 130                         acpi_nvs_nosave_s3();
 131                 if (strncmp(str, "old_ordering", 12) == 0)
 132                         acpi_old_suspend_ordering();
 133                 str = strchr(str, ',');
 134                 if (str != NULL)
 135                         str += strspn(str, ", \t");
 136         }
 137         return 1;
 138 }
 139
 140 __setup("acpi_sleep=", acpi_sleep_setup);