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 */
x86_acpi_enter_sleep_state(u8 state)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 */
x86_acpi_suspend_lowlevel(void)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
acpi_sleep_setup(char * str)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