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 */
acpi_get_wakeup_address(void)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 assmebly.
45 */
x86_acpi_enter_sleep_state(u8 state)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 */
x86_acpi_suspend_lowlevel(void)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
acpi_sleep_setup(char * str)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