xref: /openbmc/linux/arch/x86/kernel/acpi/sleep.c (revision 39b6f3aa)
1 /*
2  * sleep.c - x86-specific ACPI sleep support.
3  *
4  *  Copyright (C) 2001-2003 Patrick Mochel
5  *  Copyright (C) 2001-2003 Pavel Machek <pavel@ucw.cz>
6  */
7 
8 #include <linux/acpi.h>
9 #include <linux/bootmem.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 "../../realmode/rm/wakeup.h"
20 #include "sleep.h"
21 
22 unsigned long acpi_realmode_flags;
23 
24 #if defined(CONFIG_SMP) && defined(CONFIG_64BIT)
25 static char temp_stack[4096];
26 #endif
27 
28 /**
29  * acpi_suspend_lowlevel - save kernel state
30  *
31  * Create an identity mapped page table and copy the wakeup routine to
32  * low memory.
33  */
34 int acpi_suspend_lowlevel(void)
35 {
36 	struct wakeup_header *header =
37 		(struct wakeup_header *) __va(real_mode_header->wakeup_header);
38 
39 	if (header->signature != WAKEUP_HEADER_SIGNATURE) {
40 		printk(KERN_ERR "wakeup header does not match\n");
41 		return -EINVAL;
42 	}
43 
44 	header->video_mode = saved_video_mode;
45 
46 	header->pmode_behavior = 0;
47 
48 #ifndef CONFIG_64BIT
49 	native_store_gdt((struct desc_ptr *)&header->pmode_gdt);
50 
51 	if (!rdmsr_safe(MSR_EFER,
52 			&header->pmode_efer_low,
53 			&header->pmode_efer_high))
54 		header->pmode_behavior |= (1 << WAKEUP_BEHAVIOR_RESTORE_EFER);
55 #endif /* !CONFIG_64BIT */
56 
57 	header->pmode_cr0 = read_cr0();
58 	if (__this_cpu_read(cpu_info.cpuid_level) >= 0) {
59 		header->pmode_cr4 = read_cr4();
60 		header->pmode_behavior |= (1 << WAKEUP_BEHAVIOR_RESTORE_CR4);
61 	}
62 	if (!rdmsr_safe(MSR_IA32_MISC_ENABLE,
63 			&header->pmode_misc_en_low,
64 			&header->pmode_misc_en_high))
65 		header->pmode_behavior |=
66 			(1 << WAKEUP_BEHAVIOR_RESTORE_MISC_ENABLE);
67 	header->realmode_flags = acpi_realmode_flags;
68 	header->real_magic = 0x12345678;
69 
70 #ifndef CONFIG_64BIT
71 	header->pmode_entry = (u32)&wakeup_pmode_return;
72 	header->pmode_cr3 = (u32)__pa_symbol(initial_page_table);
73 	saved_magic = 0x12345678;
74 #else /* CONFIG_64BIT */
75 #ifdef CONFIG_SMP
76 	stack_start = (unsigned long)temp_stack + sizeof(temp_stack);
77 	early_gdt_descr.address =
78 			(unsigned long)get_cpu_gdt_table(smp_processor_id());
79 	initial_gs = per_cpu_offset(smp_processor_id());
80 #endif
81 	initial_code = (unsigned long)wakeup_long64;
82        saved_magic = 0x123456789abcdef0L;
83 #endif /* CONFIG_64BIT */
84 
85 	do_suspend_lowlevel();
86 	return 0;
87 }
88 
89 static int __init acpi_sleep_setup(char *str)
90 {
91 	while ((str != NULL) && (*str != '\0')) {
92 		if (strncmp(str, "s3_bios", 7) == 0)
93 			acpi_realmode_flags |= 1;
94 		if (strncmp(str, "s3_mode", 7) == 0)
95 			acpi_realmode_flags |= 2;
96 		if (strncmp(str, "s3_beep", 7) == 0)
97 			acpi_realmode_flags |= 4;
98 #ifdef CONFIG_HIBERNATION
99 		if (strncmp(str, "s4_nohwsig", 10) == 0)
100 			acpi_no_s4_hw_signature();
101 #endif
102 		if (strncmp(str, "nonvs", 5) == 0)
103 			acpi_nvs_nosave();
104 		if (strncmp(str, "nonvs_s3", 8) == 0)
105 			acpi_nvs_nosave_s3();
106 		if (strncmp(str, "old_ordering", 12) == 0)
107 			acpi_old_suspend_ordering();
108 		str = strchr(str, ',');
109 		if (str != NULL)
110 			str += strspn(str, ", \t");
111 	}
112 	return 1;
113 }
114 
115 __setup("acpi_sleep=", acpi_sleep_setup);
116