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/bootmem.h> 11 #include <linux/memblock.h> 12 #include <linux/dmi.h> 13 #include <linux/cpumask.h> 14 #include <asm/segment.h> 15 #include <asm/desc.h> 16 #include <asm/pgtable.h> 17 #include <asm/cacheflush.h> 18 #include <asm/realmode.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 * x86_acpi_enter_sleep_state - enter sleep state 32 * @state: Sleep state to enter. 33 * 34 * Wrapper around acpi_enter_sleep_state() to be called by assmebly. 35 */ 36 acpi_status asmlinkage __visible x86_acpi_enter_sleep_state(u8 state) 37 { 38 return acpi_enter_sleep_state(state); 39 } 40 41 /** 42 * x86_acpi_suspend_lowlevel - save kernel state 43 * 44 * Create an identity mapped page table and copy the wakeup routine to 45 * low memory. 46 */ 47 int x86_acpi_suspend_lowlevel(void) 48 { 49 struct wakeup_header *header = 50 (struct wakeup_header *) __va(real_mode_header->wakeup_header); 51 52 if (header->signature != WAKEUP_HEADER_SIGNATURE) { 53 printk(KERN_ERR "wakeup header does not match\n"); 54 return -EINVAL; 55 } 56 57 header->video_mode = saved_video_mode; 58 59 header->pmode_behavior = 0; 60 61 #ifndef CONFIG_64BIT 62 native_store_gdt((struct desc_ptr *)&header->pmode_gdt); 63 64 /* 65 * We have to check that we can write back the value, and not 66 * just read it. At least on 90 nm Pentium M (Family 6, Model 67 * 13), reading an invalid MSR is not guaranteed to trap, see 68 * Erratum X4 in "Intel Pentium M Processor on 90 nm Process 69 * with 2-MB L2 Cache and Intel® Processor A100 and A110 on 90 70 * nm process with 512-KB L2 Cache Specification Update". 71 */ 72 if (!rdmsr_safe(MSR_EFER, 73 &header->pmode_efer_low, 74 &header->pmode_efer_high) && 75 !wrmsr_safe(MSR_EFER, 76 header->pmode_efer_low, 77 header->pmode_efer_high)) 78 header->pmode_behavior |= (1 << WAKEUP_BEHAVIOR_RESTORE_EFER); 79 #endif /* !CONFIG_64BIT */ 80 81 header->pmode_cr0 = read_cr0(); 82 if (__this_cpu_read(cpu_info.cpuid_level) >= 0) { 83 header->pmode_cr4 = __read_cr4(); 84 header->pmode_behavior |= (1 << WAKEUP_BEHAVIOR_RESTORE_CR4); 85 } 86 if (!rdmsr_safe(MSR_IA32_MISC_ENABLE, 87 &header->pmode_misc_en_low, 88 &header->pmode_misc_en_high) && 89 !wrmsr_safe(MSR_IA32_MISC_ENABLE, 90 header->pmode_misc_en_low, 91 header->pmode_misc_en_high)) 92 header->pmode_behavior |= 93 (1 << WAKEUP_BEHAVIOR_RESTORE_MISC_ENABLE); 94 header->realmode_flags = acpi_realmode_flags; 95 header->real_magic = 0x12345678; 96 97 #ifndef CONFIG_64BIT 98 header->pmode_entry = (u32)&wakeup_pmode_return; 99 header->pmode_cr3 = (u32)__pa_symbol(initial_page_table); 100 saved_magic = 0x12345678; 101 #else /* CONFIG_64BIT */ 102 #ifdef CONFIG_SMP 103 initial_stack = (unsigned long)temp_stack + sizeof(temp_stack); 104 early_gdt_descr.address = 105 (unsigned long)get_cpu_gdt_rw(smp_processor_id()); 106 initial_gs = per_cpu_offset(smp_processor_id()); 107 #endif 108 initial_code = (unsigned long)wakeup_long64; 109 saved_magic = 0x123456789abcdef0L; 110 #endif /* CONFIG_64BIT */ 111 112 /* 113 * Pause/unpause graph tracing around do_suspend_lowlevel as it has 114 * inconsistent call/return info after it jumps to the wakeup vector. 115 */ 116 pause_graph_tracing(); 117 do_suspend_lowlevel(); 118 unpause_graph_tracing(); 119 return 0; 120 } 121 122 static int __init acpi_sleep_setup(char *str) 123 { 124 while ((str != NULL) && (*str != '\0')) { 125 if (strncmp(str, "s3_bios", 7) == 0) 126 acpi_realmode_flags |= 1; 127 if (strncmp(str, "s3_mode", 7) == 0) 128 acpi_realmode_flags |= 2; 129 if (strncmp(str, "s3_beep", 7) == 0) 130 acpi_realmode_flags |= 4; 131 #ifdef CONFIG_HIBERNATION 132 if (strncmp(str, "s4_nohwsig", 10) == 0) 133 acpi_no_s4_hw_signature(); 134 #endif 135 if (strncmp(str, "nonvs", 5) == 0) 136 acpi_nvs_nosave(); 137 if (strncmp(str, "nonvs_s3", 8) == 0) 138 acpi_nvs_nosave_s3(); 139 if (strncmp(str, "old_ordering", 12) == 0) 140 acpi_old_suspend_ordering(); 141 if (strncmp(str, "nobl", 4) == 0) 142 acpi_sleep_no_blacklist(); 143 str = strchr(str, ','); 144 if (str != NULL) 145 str += strspn(str, ", \t"); 146 } 147 return 1; 148 } 149 150 __setup("acpi_sleep=", acpi_sleep_setup); 151