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 <linux/ftrace.h>
20#include "../../realmode/rm/wakeup.h"
21#include "sleep.h"
22
23unsigned long acpi_realmode_flags;
24
25#if defined(CONFIG_SMP) && defined(CONFIG_64BIT)
26static 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 */
35acpi_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 */
46int 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	stack_start = (unsigned long)temp_stack + sizeof(temp_stack);
103	early_gdt_descr.address =
104			(unsigned long)get_cpu_gdt_table(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
121static 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		str = strchr(str, ',');
141		if (str != NULL)
142			str += strspn(str, ", \t");
143	}
144	return 1;
145}
146
147__setup("acpi_sleep=", acpi_sleep_setup);
148