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 * acpi_get_wakeup_address - provide physical address for S3 wakeup
  31 *
  32 * Returns the physical address where the kernel should be resumed after the
  33 * system awakes from S3, e.g. for programming into the firmware waking vector.
  34 */
  35unsigned long acpi_get_wakeup_address(void)
  36{
  37        return ((unsigned long)(real_mode_header->wakeup_start));
  38}
  39
  40/**
  41 * x86_acpi_enter_sleep_state - enter sleep state
  42 * @state: Sleep state to enter.
  43 *
  44 * Wrapper around acpi_enter_sleep_state() to be called by assmebly.
  45 */
  46acpi_status asmlinkage __visible x86_acpi_enter_sleep_state(u8 state)
  47{
  48        return acpi_enter_sleep_state(state);
  49}
  50
  51/**
  52 * x86_acpi_suspend_lowlevel - save kernel state
  53 *
  54 * Create an identity mapped page table and copy the wakeup routine to
  55 * low memory.
  56 */
  57int x86_acpi_suspend_lowlevel(void)
  58{
  59        struct wakeup_header *header =
  60                (struct wakeup_header *) __va(real_mode_header->wakeup_header);
  61
  62        if (header->signature != WAKEUP_HEADER_SIGNATURE) {
  63                printk(KERN_ERR "wakeup header does not match\n");
  64                return -EINVAL;
  65        }
  66
  67        header->video_mode = saved_video_mode;
  68
  69        header->pmode_behavior = 0;
  70
  71#ifndef CONFIG_64BIT
  72        native_store_gdt((struct desc_ptr *)&header->pmode_gdt);
  73
  74        /*
  75         * We have to check that we can write back the value, and not
  76         * just read it.  At least on 90 nm Pentium M (Family 6, Model
  77         * 13), reading an invalid MSR is not guaranteed to trap, see
  78         * Erratum X4 in "Intel Pentium M Processor on 90 nm Process
  79         * with 2-MB L2 Cache and Intel® Processor A100 and A110 on 90
  80         * nm process with 512-KB L2 Cache Specification Update".
  81         */
  82        if (!rdmsr_safe(MSR_EFER,
  83                        &header->pmode_efer_low,
  84                        &header->pmode_efer_high) &&
  85            !wrmsr_safe(MSR_EFER,
  86                        header->pmode_efer_low,
  87                        header->pmode_efer_high))
  88                header->pmode_behavior |= (1 << WAKEUP_BEHAVIOR_RESTORE_EFER);
  89#endif /* !CONFIG_64BIT */
  90
  91        header->pmode_cr0 = read_cr0();
  92        if (__this_cpu_read(cpu_info.cpuid_level) >= 0) {
  93                header->pmode_cr4 = __read_cr4();
  94                header->pmode_behavior |= (1 << WAKEUP_BEHAVIOR_RESTORE_CR4);
  95        }
  96        if (!rdmsr_safe(MSR_IA32_MISC_ENABLE,
  97                        &header->pmode_misc_en_low,
  98                        &header->pmode_misc_en_high) &&
  99            !wrmsr_safe(MSR_IA32_MISC_ENABLE,
 100                        header->pmode_misc_en_low,
 101                        header->pmode_misc_en_high))
 102                header->pmode_behavior |=
 103                        (1 << WAKEUP_BEHAVIOR_RESTORE_MISC_ENABLE);
 104        header->realmode_flags = acpi_realmode_flags;
 105        header->real_magic = 0x12345678;
 106
 107#ifndef CONFIG_64BIT
 108        header->pmode_entry = (u32)&wakeup_pmode_return;
 109        header->pmode_cr3 = (u32)__pa_symbol(initial_page_table);
 110        saved_magic = 0x12345678;
 111#else /* CONFIG_64BIT */
 112#ifdef CONFIG_SMP
 113        initial_stack = (unsigned long)temp_stack + sizeof(temp_stack);
 114        early_gdt_descr.address =
 115                        (unsigned long)get_cpu_gdt_rw(smp_processor_id());
 116        initial_gs = per_cpu_offset(smp_processor_id());
 117#endif
 118        initial_code = (unsigned long)wakeup_long64;
 119       saved_magic = 0x123456789abcdef0L;
 120#endif /* CONFIG_64BIT */
 121
 122        /*
 123         * Pause/unpause graph tracing around do_suspend_lowlevel as it has
 124         * inconsistent call/return info after it jumps to the wakeup vector.
 125         */
 126        pause_graph_tracing();
 127        do_suspend_lowlevel();
 128        unpause_graph_tracing();
 129        return 0;
 130}
 131
 132static int __init acpi_sleep_setup(char *str)
 133{
 134        while ((str != NULL) && (*str != '\0')) {
 135                if (strncmp(str, "s3_bios", 7) == 0)
 136                        acpi_realmode_flags |= 1;
 137                if (strncmp(str, "s3_mode", 7) == 0)
 138                        acpi_realmode_flags |= 2;
 139                if (strncmp(str, "s3_beep", 7) == 0)
 140                        acpi_realmode_flags |= 4;
 141#ifdef CONFIG_HIBERNATION
 142                if (strncmp(str, "s4_nohwsig", 10) == 0)
 143                        acpi_no_s4_hw_signature();
 144#endif
 145                if (strncmp(str, "nonvs", 5) == 0)
 146                        acpi_nvs_nosave();
 147                if (strncmp(str, "nonvs_s3", 8) == 0)
 148                        acpi_nvs_nosave_s3();
 149                if (strncmp(str, "old_ordering", 12) == 0)
 150                        acpi_old_suspend_ordering();
 151                if (strncmp(str, "nobl", 4) == 0)
 152                        acpi_sleep_no_blacklist();
 153                str = strchr(str, ',');
 154                if (str != NULL)
 155                        str += strspn(str, ", \t");
 156        }
 157        return 1;
 158}
 159
 160__setup("acpi_sleep=", acpi_sleep_setup);
 161