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 assembly. 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); 161