LXR linux/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
  22unsigned long acpi_realmode_flags;
  23
  24#if defined(CONFIG_SMP) && defined(CONFIG_64BIT)
  25static char temp_stack[4096];
  26#endif
  27
  28/**
  29 * x86_acpi_suspend_lowlevel - save kernel state
  30 *
  31 * Create an identity mapped page table and copy the wakeup routine to
  32 * low memory.
  33 */
  34int x86_acpi_suspend_lowlevel(void)
  35{
  36        struct wakeup_header *header =
  37                (struct wakeup_header *) __va(real_mode_header->wakeup_header);
  38
  39        if (header->signature != WAKEUP_HEADER_SIGNATURE) {
  40                printk(KERN_ERR "wakeup header does not match\n");
  41                return -EINVAL;
  42        }
  43
  44        header->video_mode = saved_video_mode;
  45
  46        header->pmode_behavior = 0;
  47
  48#ifndef CONFIG_64BIT
  49        native_store_gdt((struct desc_ptr *)&header->pmode_gdt);
  50
  51        /*
  52         * We have to check that we can write back the value, and not
  53         * just read it.  At least on 90 nm Pentium M (Family 6, Model
  54         * 13), reading an invalid MSR is not guaranteed to trap, see
  55         * Erratum X4 in "Intel Pentium M Processor on 90 nm Process
  56         * with 2-MB L2 Cache and Intel® Processor A100 and A110 on 90
  57         * nm process with 512-KB L2 Cache Specification Update".
  58         */
  59        if (!rdmsr_safe(MSR_EFER,
  60                        &header->pmode_efer_low,
  61                        &header->pmode_efer_high) &&
  62            !wrmsr_safe(MSR_EFER,
  63                        header->pmode_efer_low,
  64                        header->pmode_efer_high))
  65                header->pmode_behavior |= (1 << WAKEUP_BEHAVIOR_RESTORE_EFER);
  66#endif /* !CONFIG_64BIT */
  67
  68        header->pmode_cr0 = read_cr0();
  69        if (__this_cpu_read(cpu_info.cpuid_level) >= 0) {
  70                header->pmode_cr4 = read_cr4();
  71                header->pmode_behavior |= (1 << WAKEUP_BEHAVIOR_RESTORE_CR4);
  72        }
  73        if (!rdmsr_safe(MSR_IA32_MISC_ENABLE,
  74                        &header->pmode_misc_en_low,
  75                        &header->pmode_misc_en_high) &&
  76            !wrmsr_safe(MSR_IA32_MISC_ENABLE,
  77                        header->pmode_misc_en_low,
  78                        header->pmode_misc_en_high))
  79                header->pmode_behavior |=
  80                        (1 << WAKEUP_BEHAVIOR_RESTORE_MISC_ENABLE);
  81        header->realmode_flags = acpi_realmode_flags;
  82        header->real_magic = 0x12345678;
  83
  84#ifndef CONFIG_64BIT
  85        header->pmode_entry = (u32)&wakeup_pmode_return;
  86        header->pmode_cr3 = (u32)__pa_symbol(initial_page_table);
  87        saved_magic = 0x12345678;
  88#else /* CONFIG_64BIT */
  89#ifdef CONFIG_SMP
  90        stack_start = (unsigned long)temp_stack + sizeof(temp_stack);
  91        early_gdt_descr.address =
  92                        (unsigned long)get_cpu_gdt_table(smp_processor_id());
  93        initial_gs = per_cpu_offset(smp_processor_id());
  94#endif
  95        initial_code = (unsigned long)wakeup_long64;
  96       saved_magic = 0x123456789abcdef0L;
  97#endif /* CONFIG_64BIT */
  98
  99        do_suspend_lowlevel();
 100        return 0;
 101}
 102
 103static int __init acpi_sleep_setup(char *str)
 104{
 105        while ((str != NULL) && (*str != '\0')) {
 106                if (strncmp(str, "s3_bios", 7) == 0)
 107                        acpi_realmode_flags |= 1;
 108                if (strncmp(str, "s3_mode", 7) == 0)
 109                        acpi_realmode_flags |= 2;
 110                if (strncmp(str, "s3_beep", 7) == 0)
 111                        acpi_realmode_flags |= 4;
 112#ifdef CONFIG_HIBERNATION
 113                if (strncmp(str, "s4_nohwsig", 10) == 0)
 114                        acpi_no_s4_hw_signature();
 115#endif
 116                if (strncmp(str, "nonvs", 5) == 0)
 117                        acpi_nvs_nosave();
 118                if (strncmp(str, "nonvs_s3", 8) == 0)
 119                        acpi_nvs_nosave_s3();
 120                if (strncmp(str, "old_ordering", 12) == 0)
 121                        acpi_old_suspend_ordering();
 122                str = strchr(str, ',');
 123                if (str != NULL)
 124                        str += strspn(str, ", \t");
 125        }
 126        return 1;
 127}
 128
 129__setup("acpi_sleep=", acpi_sleep_setup);
 130