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 <linux/pgtable.h>
  14 #include <asm/segment.h>
  15 #include <asm/desc.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
  23 unsigned long acpi_realmode_flags;
  24
  25 #if defined(CONFIG_SMP) && defined(CONFIG_64BIT)
  26 static 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  */
  35 unsigned 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  */
  46 asmlinkage acpi_status __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  */
  57 int 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
 132 static 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);