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 | #include <asm/smp.h> |
20 | |
21 | #include <linux/ftrace.h> |
22 | #include "../../realmode/rm/wakeup.h" |
23 | #include "sleep.h" |
24 | |
25 | unsigned long acpi_realmode_flags; |
26 | |
27 | #if defined(CONFIG_SMP) && defined(CONFIG_64BIT) |
28 | static char temp_stack[4096]; |
29 | #endif |
30 | |
31 | /** |
32 | * acpi_get_wakeup_address - provide physical address for S3 wakeup |
33 | * |
34 | * Returns the physical address where the kernel should be resumed after the |
35 | * system awakes from S3, e.g. for programming into the firmware waking vector. |
36 | */ |
37 | unsigned long acpi_get_wakeup_address(void) |
38 | { |
39 | return ((unsigned long)(real_mode_header->wakeup_start)); |
40 | } |
41 | |
42 | /** |
43 | * x86_acpi_enter_sleep_state - enter sleep state |
44 | * @state: Sleep state to enter. |
45 | * |
46 | * Wrapper around acpi_enter_sleep_state() to be called by assembly. |
47 | */ |
48 | asmlinkage acpi_status __visible x86_acpi_enter_sleep_state(u8 state) |
49 | { |
50 | return acpi_enter_sleep_state(sleep_state: state); |
51 | } |
52 | |
53 | /** |
54 | * x86_acpi_suspend_lowlevel - save kernel state |
55 | * |
56 | * Create an identity mapped page table and copy the wakeup routine to |
57 | * low memory. |
58 | */ |
59 | int x86_acpi_suspend_lowlevel(void) |
60 | { |
61 | struct wakeup_header * = |
62 | (struct wakeup_header *) __va(real_mode_header->wakeup_header); |
63 | |
64 | if (header->signature != WAKEUP_HEADER_SIGNATURE) { |
65 | printk(KERN_ERR "wakeup header does not match\n" ); |
66 | return -EINVAL; |
67 | } |
68 | |
69 | header->video_mode = saved_video_mode; |
70 | |
71 | header->pmode_behavior = 0; |
72 | |
73 | #ifndef CONFIG_64BIT |
74 | native_store_gdt((struct desc_ptr *)&header->pmode_gdt); |
75 | |
76 | /* |
77 | * We have to check that we can write back the value, and not |
78 | * just read it. At least on 90 nm Pentium M (Family 6, Model |
79 | * 13), reading an invalid MSR is not guaranteed to trap, see |
80 | * Erratum X4 in "Intel Pentium M Processor on 90 nm Process |
81 | * with 2-MB L2 Cache and IntelĀ® Processor A100 and A110 on 90 |
82 | * nm process with 512-KB L2 Cache Specification Update". |
83 | */ |
84 | if (!rdmsr_safe(MSR_EFER, |
85 | &header->pmode_efer_low, |
86 | &header->pmode_efer_high) && |
87 | !wrmsr_safe(MSR_EFER, |
88 | header->pmode_efer_low, |
89 | header->pmode_efer_high)) |
90 | header->pmode_behavior |= (1 << WAKEUP_BEHAVIOR_RESTORE_EFER); |
91 | #endif /* !CONFIG_64BIT */ |
92 | |
93 | header->pmode_cr0 = read_cr0(); |
94 | if (__this_cpu_read(cpu_info.cpuid_level) >= 0) { |
95 | header->pmode_cr4 = __read_cr4(); |
96 | header->pmode_behavior |= (1 << WAKEUP_BEHAVIOR_RESTORE_CR4); |
97 | } |
98 | if (!rdmsr_safe(MSR_IA32_MISC_ENABLE, |
99 | &header->pmode_misc_en_low, |
100 | &header->pmode_misc_en_high) && |
101 | !wrmsr_safe(MSR_IA32_MISC_ENABLE, |
102 | header->pmode_misc_en_low, |
103 | header->pmode_misc_en_high)) |
104 | header->pmode_behavior |= |
105 | (1 << WAKEUP_BEHAVIOR_RESTORE_MISC_ENABLE); |
106 | header->realmode_flags = acpi_realmode_flags; |
107 | header->real_magic = 0x12345678; |
108 | |
109 | #ifndef CONFIG_64BIT |
110 | header->pmode_entry = (u32)&wakeup_pmode_return; |
111 | header->pmode_cr3 = (u32)__pa_symbol(initial_page_table); |
112 | saved_magic = 0x12345678; |
113 | #else /* CONFIG_64BIT */ |
114 | #ifdef CONFIG_SMP |
115 | /* |
116 | * As each CPU starts up, it will find its own stack pointer |
117 | * from its current_task->thread.sp. Typically that will be |
118 | * the idle thread for a newly-started AP, or even the boot |
119 | * CPU which will find it set to &init_task in the static |
120 | * per-cpu data. |
121 | * |
122 | * Make the resuming CPU use the temporary stack at startup |
123 | * by setting current->thread.sp to point to that. The true |
124 | * %rsp will be restored with the rest of the CPU context, |
125 | * by do_suspend_lowlevel(). And unwinders don't care about |
126 | * the abuse of ->thread.sp because it's a dead variable |
127 | * while the thread is running on the CPU anyway; the true |
128 | * value is in the actual %rsp register. |
129 | */ |
130 | current->thread.sp = (unsigned long)temp_stack + sizeof(temp_stack); |
131 | /* |
132 | * Ensure the CPU knows which one it is when it comes back, if |
133 | * it isn't in parallel mode and expected to work that out for |
134 | * itself. |
135 | */ |
136 | if (!(smpboot_control & STARTUP_PARALLEL_MASK)) |
137 | smpboot_control = smp_processor_id(); |
138 | #endif |
139 | initial_code = (unsigned long)wakeup_long64; |
140 | saved_magic = 0x123456789abcdef0L; |
141 | #endif /* CONFIG_64BIT */ |
142 | |
143 | /* |
144 | * Pause/unpause graph tracing around do_suspend_lowlevel as it has |
145 | * inconsistent call/return info after it jumps to the wakeup vector. |
146 | */ |
147 | pause_graph_tracing(); |
148 | do_suspend_lowlevel(); |
149 | unpause_graph_tracing(); |
150 | return 0; |
151 | } |
152 | |
153 | static int __init acpi_sleep_setup(char *str) |
154 | { |
155 | while ((str != NULL) && (*str != '\0')) { |
156 | if (strncmp(str, "s3_bios" , 7) == 0) |
157 | acpi_realmode_flags |= 1; |
158 | if (strncmp(str, "s3_mode" , 7) == 0) |
159 | acpi_realmode_flags |= 2; |
160 | if (strncmp(str, "s3_beep" , 7) == 0) |
161 | acpi_realmode_flags |= 4; |
162 | #ifdef CONFIG_HIBERNATION |
163 | if (strncmp(str, "s4_hwsig" , 8) == 0) |
164 | acpi_check_s4_hw_signature = 1; |
165 | if (strncmp(str, "s4_nohwsig" , 10) == 0) |
166 | acpi_check_s4_hw_signature = 0; |
167 | #endif |
168 | if (strncmp(str, "nonvs" , 5) == 0) |
169 | acpi_nvs_nosave(); |
170 | if (strncmp(str, "nonvs_s3" , 8) == 0) |
171 | acpi_nvs_nosave_s3(); |
172 | if (strncmp(str, "old_ordering" , 12) == 0) |
173 | acpi_old_suspend_ordering(); |
174 | if (strncmp(str, "nobl" , 4) == 0) |
175 | acpi_sleep_no_blacklist(); |
176 | str = strchr(str, ','); |
177 | if (str != NULL) |
178 | str += strspn(str, ", \t" ); |
179 | } |
180 | return 1; |
181 | } |
182 | |
183 | __setup("acpi_sleep=" , acpi_sleep_setup); |
184 | |
185 | #if defined(CONFIG_HIBERNATION) && defined(CONFIG_HYPERVISOR_GUEST) |
186 | static int __init init_s4_sigcheck(void) |
187 | { |
188 | /* |
189 | * If running on a hypervisor, honour the ACPI specification |
190 | * by default and trigger a clean reboot when the hardware |
191 | * signature in FACS is changed after hibernation. |
192 | */ |
193 | if (acpi_check_s4_hw_signature == -1 && |
194 | !hypervisor_is_type(type: X86_HYPER_NATIVE)) |
195 | acpi_check_s4_hw_signature = 1; |
196 | |
197 | return 0; |
198 | } |
199 | /* This must happen before acpi_init() which is a subsys initcall */ |
200 | arch_initcall(init_s4_sigcheck); |
201 | #endif |
202 | |