xref: /openbmc/linux/arch/x86/kernel/acpi/sleep.c (revision 15e47304)
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 #ifndef CONFIG_64BIT
47 	store_gdt((struct desc_ptr *)&header->pmode_gdt);
48 
49 	if (rdmsr_safe(MSR_EFER, &header->pmode_efer_low,
50 		       &header->pmode_efer_high))
51 		header->pmode_efer_low = header->pmode_efer_high = 0;
52 #endif /* !CONFIG_64BIT */
53 
54 	header->pmode_cr0 = read_cr0();
55 	header->pmode_cr4 = read_cr4_safe();
56 	header->pmode_behavior = 0;
57 	if (!rdmsr_safe(MSR_IA32_MISC_ENABLE,
58 			&header->pmode_misc_en_low,
59 			&header->pmode_misc_en_high))
60 		header->pmode_behavior |=
61 			(1 << WAKEUP_BEHAVIOR_RESTORE_MISC_ENABLE);
62 	header->realmode_flags = acpi_realmode_flags;
63 	header->real_magic = 0x12345678;
64 
65 #ifndef CONFIG_64BIT
66 	header->pmode_entry = (u32)&wakeup_pmode_return;
67 	header->pmode_cr3 = (u32)__pa(&initial_page_table);
68 	saved_magic = 0x12345678;
69 #else /* CONFIG_64BIT */
70 #ifdef CONFIG_SMP
71 	stack_start = (unsigned long)temp_stack + sizeof(temp_stack);
72 	early_gdt_descr.address =
73 			(unsigned long)get_cpu_gdt_table(smp_processor_id());
74 	initial_gs = per_cpu_offset(smp_processor_id());
75 #endif
76 	initial_code = (unsigned long)wakeup_long64;
77        saved_magic = 0x123456789abcdef0L;
78 #endif /* CONFIG_64BIT */
79 
80 	do_suspend_lowlevel();
81 	return 0;
82 }
83 
84 static int __init acpi_sleep_setup(char *str)
85 {
86 	while ((str != NULL) && (*str != '\0')) {
87 		if (strncmp(str, "s3_bios", 7) == 0)
88 			acpi_realmode_flags |= 1;
89 		if (strncmp(str, "s3_mode", 7) == 0)
90 			acpi_realmode_flags |= 2;
91 		if (strncmp(str, "s3_beep", 7) == 0)
92 			acpi_realmode_flags |= 4;
93 #ifdef CONFIG_HIBERNATION
94 		if (strncmp(str, "s4_nohwsig", 10) == 0)
95 			acpi_no_s4_hw_signature();
96 #endif
97 		if (strncmp(str, "nonvs", 5) == 0)
98 			acpi_nvs_nosave();
99 		if (strncmp(str, "old_ordering", 12) == 0)
100 			acpi_old_suspend_ordering();
101 		str = strchr(str, ',');
102 		if (str != NULL)
103 			str += strspn(str, ", \t");
104 	}
105 	return 1;
106 }
107 
108 __setup("acpi_sleep=", acpi_sleep_setup);
109