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 182