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 #include <asm/hypervisor.h>
  19
  20 #include <linux/ftrace.h>
  21 #include "../../realmode/rm/wakeup.h"
  22 #include "sleep.h"
  23
  24 unsigned long acpi_realmode_flags;
  25
  26 #if defined(CONFIG_SMP) && defined(CONFIG_64BIT)
  27 static char temp_stack[4096];
  28 #endif
  29
  30 /**
  31  * acpi_get_wakeup_address - provide physical address for S3 wakeup
  32  *
  33  * Returns the physical address where the kernel should be resumed after the
  34  * system awakes from S3, e.g. for programming into the firmware waking vector.
  35  */
  36 unsigned long acpi_get_wakeup_address(void)
  37 {
  38         return ((unsigned long)(real_mode_header->wakeup_start));
  39 }
  40
  41 /**
  42  * x86_acpi_enter_sleep_state - enter sleep state
  43  * @state: Sleep state to enter.
  44  *
  45  * Wrapper around acpi_enter_sleep_state() to be called by assembly.
  46  */
  47 asmlinkage acpi_status __visible x86_acpi_enter_sleep_state(u8 state)
  48 {
  49         return acpi_enter_sleep_state(state);
  50 }
  51
  52 /**
  53  * x86_acpi_suspend_lowlevel - save kernel state
  54  *
  55  * Create an identity mapped page table and copy the wakeup routine to
  56  * low memory.
  57  */
  58 int x86_acpi_suspend_lowlevel(void)
  59 {
  60         struct wakeup_header *header =
  61                 (struct wakeup_header *) __va(real_mode_header->wakeup_header);
  62
  63         if (header->signature != WAKEUP_HEADER_SIGNATURE) {
  64                 printk(KERN_ERR "wakeup header does not match\n");
  65                 return -EINVAL;
  66         }
  67
  68         header->video_mode = saved_video_mode;
  69
  70         header->pmode_behavior = 0;
  71
  72 #ifndef CONFIG_64BIT
  73         native_store_gdt((struct desc_ptr *)&header->pmode_gdt);
  74
  75         /*
  76          * We have to check that we can write back the value, and not
  77          * just read it.  At least on 90 nm Pentium M (Family 6, Model
  78          * 13), reading an invalid MSR is not guaranteed to trap, see
  79          * Erratum X4 in "Intel Pentium M Processor on 90 nm Process
  80          * with 2-MB L2 Cache and Intel® Processor A100 and A110 on 90
  81          * nm process with 512-KB L2 Cache Specification Update".
  82          */
  83         if (!rdmsr_safe(MSR_EFER,
  84                         &header->pmode_efer_low,
  85                         &header->pmode_efer_high) &&
  86             !wrmsr_safe(MSR_EFER,
  87                         header->pmode_efer_low,
  88                         header->pmode_efer_high))
  89                 header->pmode_behavior |= (1 << WAKEUP_BEHAVIOR_RESTORE_EFER);
  90 #endif /* !CONFIG_64BIT */
  91
  92         header->pmode_cr0 = read_cr0();
  93         if (__this_cpu_read(cpu_info.cpuid_level) >= 0) {
  94                 header->pmode_cr4 = __read_cr4();
  95                 header->pmode_behavior |= (1 << WAKEUP_BEHAVIOR_RESTORE_CR4);
  96         }
  97         if (!rdmsr_safe(MSR_IA32_MISC_ENABLE,
  98                         &header->pmode_misc_en_low,
  99                         &header->pmode_misc_en_high) &&
 100             !wrmsr_safe(MSR_IA32_MISC_ENABLE,
 101                         header->pmode_misc_en_low,
 102                         header->pmode_misc_en_high))
 103                 header->pmode_behavior |=
 104                         (1 << WAKEUP_BEHAVIOR_RESTORE_MISC_ENABLE);
 105         header->realmode_flags = acpi_realmode_flags;
 106         header->real_magic = 0x12345678;
 107
 108 #ifndef CONFIG_64BIT
 109         header->pmode_entry = (u32)&wakeup_pmode_return;
 110         header->pmode_cr3 = (u32)__pa_symbol(initial_page_table);
 111         saved_magic = 0x12345678;
 112 #else /* CONFIG_64BIT */
 113 #ifdef CONFIG_SMP
 114         initial_stack = (unsigned long)temp_stack + sizeof(temp_stack);
 115         early_gdt_descr.address =
 116                         (unsigned long)get_cpu_gdt_rw(smp_processor_id());
 117         initial_gs = per_cpu_offset(smp_processor_id());
 118 #endif
 119         initial_code = (unsigned long)wakeup_long64;
 120        saved_magic = 0x123456789abcdef0L;
 121 #endif /* CONFIG_64BIT */
 122
 123         /*
 124          * Pause/unpause graph tracing around do_suspend_lowlevel as it has
 125          * inconsistent call/return info after it jumps to the wakeup vector.
 126          */
 127         pause_graph_tracing();
 128         do_suspend_lowlevel();
 129         unpause_graph_tracing();
 130         return 0;
 131 }
 132
 133 static int __init acpi_sleep_setup(char *str)
 134 {
 135         while ((str != NULL) && (*str != '\0')) {
 136                 if (strncmp(str, "s3_bios", 7) == 0)
 137                         acpi_realmode_flags |= 1;
 138                 if (strncmp(str, "s3_mode", 7) == 0)
 139                         acpi_realmode_flags |= 2;
 140                 if (strncmp(str, "s3_beep", 7) == 0)
 141                         acpi_realmode_flags |= 4;
 142 #ifdef CONFIG_HIBERNATION
 143                 if (strncmp(str, "s4_hwsig", 8) == 0)
 144                         acpi_check_s4_hw_signature = 1;
 145                 if (strncmp(str, "s4_nohwsig", 10) == 0)
 146                         acpi_check_s4_hw_signature = 0;
 147 #endif
 148                 if (strncmp(str, "nonvs", 5) == 0)
 149                         acpi_nvs_nosave();
 150                 if (strncmp(str, "nonvs_s3", 8) == 0)
 151                         acpi_nvs_nosave_s3();
 152                 if (strncmp(str, "old_ordering", 12) == 0)
 153                         acpi_old_suspend_ordering();
 154                 if (strncmp(str, "nobl", 4) == 0)
 155                         acpi_sleep_no_blacklist();
 156                 str = strchr(str, ',');
 157                 if (str != NULL)
 158                         str += strspn(str, ", \t");
 159         }
 160         return 1;
 161 }
 162
 163 __setup("acpi_sleep=", acpi_sleep_setup);
 164
 165 #if defined(CONFIG_HIBERNATION) && defined(CONFIG_HYPERVISOR_GUEST)
 166 static int __init init_s4_sigcheck(void)
 167 {
 168         /*
 169          * If running on a hypervisor, honour the ACPI specification
 170          * by default and trigger a clean reboot when the hardware
 171          * signature in FACS is changed after hibernation.
 172          */
 173         if (acpi_check_s4_hw_signature == -1 &&
 174             !hypervisor_is_type(X86_HYPER_NATIVE))
 175                 acpi_check_s4_hw_signature = 1;
 176
 177         return 0;
 178 }
 179 /* This must happen before acpi_init() which is a subsys initcall */
 180 arch_initcall(init_s4_sigcheck);
 181 #endif