LXR linux/arch/x86/kernel/acpi/sleep.c

   1// SPDX-License-Identifier: GPL-2.0
   2/*
   3 * sleep.c - x86-specific ACPI sleep support.
   4 *
   5 *  Copyright (C) 2001-2003 Patrick Mochel
   6 *  Copyright (C) 2001-2003 Pavel Machek <pavel@ucw.cz>
   7 */
   8
   9#include <linux/acpi.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 <linux/ftrace.h>
  20#include "../../realmode/rm/wakeup.h"
  21#include "sleep.h"
  22
  23unsigned long acpi_realmode_flags;
  24
  25#if defined(CONFIG_SMP) && defined(CONFIG_64BIT)
  26static char temp_stack[4096];
  27#endif
  28
  29/**
  30 * x86_acpi_enter_sleep_state - enter sleep state
  31 * @state: Sleep state to enter.
  32 *
  33 * Wrapper around acpi_enter_sleep_state() to be called by assmebly.
  34 */
  35acpi_status asmlinkage __visible x86_acpi_enter_sleep_state(u8 state)
  36{
  37        return acpi_enter_sleep_state(state);
  38}
  39
  40/**
  41 * x86_acpi_suspend_lowlevel - save kernel state
  42 *
  43 * Create an identity mapped page table and copy the wakeup routine to
  44 * low memory.
  45 */
  46int x86_acpi_suspend_lowlevel(void)
  47{
  48        struct wakeup_header *header =
  49                (struct wakeup_header *) __va(real_mode_header->wakeup_header);
  50
  51        if (header->signature != WAKEUP_HEADER_SIGNATURE) {
  52                printk(KERN_ERR "wakeup header does not match\n");
  53                return -EINVAL;
  54        }
  55
  56        header->video_mode = saved_video_mode;
  57
  58        header->pmode_behavior = 0;
  59
  60#ifndef CONFIG_64BIT
  61        native_store_gdt((struct desc_ptr *)&header->pmode_gdt);
  62
  63        /*
  64         * We have to check that we can write back the value, and not
  65         * just read it.  At least on 90 nm Pentium M (Family 6, Model
  66         * 13), reading an invalid MSR is not guaranteed to trap, see
  67         * Erratum X4 in "Intel Pentium M Processor on 90 nm Process
  68         * with 2-MB L2 Cache and Intel® Processor A100 and A110 on 90
  69         * nm process with 512-KB L2 Cache Specification Update".
  70         */
  71        if (!rdmsr_safe(MSR_EFER,
  72                        &header->pmode_efer_low,
  73                        &header->pmode_efer_high) &&
  74            !wrmsr_safe(MSR_EFER,
  75                        header->pmode_efer_low,
  76                        header->pmode_efer_high))
  77                header->pmode_behavior |= (1 << WAKEUP_BEHAVIOR_RESTORE_EFER);
  78#endif /* !CONFIG_64BIT */
  79
  80        header->pmode_cr0 = read_cr0();
  81        if (__this_cpu_read(cpu_info.cpuid_level) >= 0) {
  82                header->pmode_cr4 = __read_cr4();
  83                header->pmode_behavior |= (1 << WAKEUP_BEHAVIOR_RESTORE_CR4);
  84        }
  85        if (!rdmsr_safe(MSR_IA32_MISC_ENABLE,
  86                        &header->pmode_misc_en_low,
  87                        &header->pmode_misc_en_high) &&
  88            !wrmsr_safe(MSR_IA32_MISC_ENABLE,
  89                        header->pmode_misc_en_low,
  90                        header->pmode_misc_en_high))
  91                header->pmode_behavior |=
  92                        (1 << WAKEUP_BEHAVIOR_RESTORE_MISC_ENABLE);
  93        header->realmode_flags = acpi_realmode_flags;
  94        header->real_magic = 0x12345678;
  95
  96#ifndef CONFIG_64BIT
  97        header->pmode_entry = (u32)&wakeup_pmode_return;
  98        header->pmode_cr3 = (u32)__pa_symbol(initial_page_table);
  99        saved_magic = 0x12345678;
 100#else /* CONFIG_64BIT */
 101#ifdef CONFIG_SMP
 102        initial_stack = (unsigned long)temp_stack + sizeof(temp_stack);
 103        early_gdt_descr.address =
 104                        (unsigned long)get_cpu_gdt_rw(smp_processor_id());
 105        initial_gs = per_cpu_offset(smp_processor_id());
 106#endif
 107        initial_code = (unsigned long)wakeup_long64;
 108       saved_magic = 0x123456789abcdef0L;
 109#endif /* CONFIG_64BIT */
 110
 111        /*
 112         * Pause/unpause graph tracing around do_suspend_lowlevel as it has
 113         * inconsistent call/return info after it jumps to the wakeup vector.
 114         */
 115        pause_graph_tracing();
 116        do_suspend_lowlevel();
 117        unpause_graph_tracing();
 118        return 0;
 119}
 120
 121static int __init acpi_sleep_setup(char *str)
 122{
 123        while ((str != NULL) && (*str != '\0')) {
 124                if (strncmp(str, "s3_bios", 7) == 0)
 125                        acpi_realmode_flags |= 1;
 126                if (strncmp(str, "s3_mode", 7) == 0)
 127                        acpi_realmode_flags |= 2;
 128                if (strncmp(str, "s3_beep", 7) == 0)
 129                        acpi_realmode_flags |= 4;
 130#ifdef CONFIG_HIBERNATION
 131                if (strncmp(str, "s4_nohwsig", 10) == 0)
 132                        acpi_no_s4_hw_signature();
 133#endif
 134                if (strncmp(str, "nonvs", 5) == 0)
 135                        acpi_nvs_nosave();
 136                if (strncmp(str, "nonvs_s3", 8) == 0)
 137                        acpi_nvs_nosave_s3();
 138                if (strncmp(str, "old_ordering", 12) == 0)
 139                        acpi_old_suspend_ordering();
 140                if (strncmp(str, "nobl", 4) == 0)
 141                        acpi_sleep_no_blacklist();
 142                str = strchr(str, ',');
 143                if (str != NULL)
 144                        str += strspn(str, ", \t");
 145        }
 146        return 1;
 147}
 148
 149__setup("acpi_sleep=", acpi_sleep_setup);
 150