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