1/*
2 * Hibernation support for x86-64
3 *
4 * Distribute under GPLv2.
5 *
6 * Copyright 2007 Rafael J. Wysocki <rjw@sisk.pl>
7 * Copyright 2005 Andi Kleen <ak@suse.de>
8 * Copyright 2004 Pavel Machek <pavel@suse.cz>
9 *
10 * swsusp_arch_resume must not use any stack or any nonlocal variables while
11 * copying pages:
12 *
13 * Its rewriting one kernel image with another. What is stack in "old"
14 * image could very well be data page in "new" image, and overwriting
15 * your own stack under you is bad idea.
16 */
17
18	.text
19#include <linux/linkage.h>
20#include <asm/segment.h>
21#include <asm/page_types.h>
22#include <asm/asm-offsets.h>
23#include <asm/processor-flags.h>
24#include <asm/frame.h>
25
26ENTRY(swsusp_arch_suspend)
27	movq	$saved_context, %rax
28	movq	%rsp, pt_regs_sp(%rax)
29	movq	%rbp, pt_regs_bp(%rax)
30	movq	%rsi, pt_regs_si(%rax)
31	movq	%rdi, pt_regs_di(%rax)
32	movq	%rbx, pt_regs_bx(%rax)
33	movq	%rcx, pt_regs_cx(%rax)
34	movq	%rdx, pt_regs_dx(%rax)
35	movq	%r8, pt_regs_r8(%rax)
36	movq	%r9, pt_regs_r9(%rax)
37	movq	%r10, pt_regs_r10(%rax)
38	movq	%r11, pt_regs_r11(%rax)
39	movq	%r12, pt_regs_r12(%rax)
40	movq	%r13, pt_regs_r13(%rax)
41	movq	%r14, pt_regs_r14(%rax)
42	movq	%r15, pt_regs_r15(%rax)
43	pushfq
44	popq	pt_regs_flags(%rax)
45
46	/* save cr3 */
47	movq	%cr3, %rax
48	movq	%rax, restore_cr3(%rip)
49
50	FRAME_BEGIN
51	call swsusp_save
52	FRAME_END
53	ret
54ENDPROC(swsusp_arch_suspend)
55
56ENTRY(restore_image)
57	/* prepare to jump to the image kernel */
58	movq	restore_jump_address(%rip), %r8
59	movq	restore_cr3(%rip), %r9
60
61	/* prepare to switch to temporary page tables */
62	movq	temp_level4_pgt(%rip), %rax
63	movq	mmu_cr4_features(%rip), %rbx
64
65	/* prepare to copy image data to their original locations */
66	movq	restore_pblist(%rip), %rdx
67
68	/* jump to relocated restore code */
69	movq	relocated_restore_code(%rip), %rcx
70	jmpq	*%rcx
71
72	/* code below has been relocated to a safe page */
73ENTRY(core_restore_code)
74	/* switch to temporary page tables */
75	movq	%rax, %cr3
76	/* flush TLB */
77	movq	%rbx, %rcx
78	andq	$~(X86_CR4_PGE), %rcx
79	movq	%rcx, %cr4;  # turn off PGE
80	movq	%cr3, %rcx;  # flush TLB
81	movq	%rcx, %cr3;
82	movq	%rbx, %cr4;  # turn PGE back on
83.Lloop:
84	testq	%rdx, %rdx
85	jz	.Ldone
86
87	/* get addresses from the pbe and copy the page */
88	movq	pbe_address(%rdx), %rsi
89	movq	pbe_orig_address(%rdx), %rdi
90	movq	$(PAGE_SIZE >> 3), %rcx
91	rep
92	movsq
93
94	/* progress to the next pbe */
95	movq	pbe_next(%rdx), %rdx
96	jmp	.Lloop
97
98.Ldone:
99	/* jump to the restore_registers address from the image header */
100	jmpq	*%r8
101
102	 /* code below belongs to the image kernel */
103	.align PAGE_SIZE
104ENTRY(restore_registers)
105	/* go back to the original page tables */
106	movq    %r9, %cr3
107
108	/* Flush TLB, including "global" things (vmalloc) */
109	movq	mmu_cr4_features(%rip), %rax
110	movq	%rax, %rdx
111	andq	$~(X86_CR4_PGE), %rdx
112	movq	%rdx, %cr4;  # turn off PGE
113	movq	%cr3, %rcx;  # flush TLB
114	movq	%rcx, %cr3
115	movq	%rax, %cr4;  # turn PGE back on
116
117	/* We don't restore %rax, it must be 0 anyway */
118	movq	$saved_context, %rax
119	movq	pt_regs_sp(%rax), %rsp
120	movq	pt_regs_bp(%rax), %rbp
121	movq	pt_regs_si(%rax), %rsi
122	movq	pt_regs_di(%rax), %rdi
123	movq	pt_regs_bx(%rax), %rbx
124	movq	pt_regs_cx(%rax), %rcx
125	movq	pt_regs_dx(%rax), %rdx
126	movq	pt_regs_r8(%rax), %r8
127	movq	pt_regs_r9(%rax), %r9
128	movq	pt_regs_r10(%rax), %r10
129	movq	pt_regs_r11(%rax), %r11
130	movq	pt_regs_r12(%rax), %r12
131	movq	pt_regs_r13(%rax), %r13
132	movq	pt_regs_r14(%rax), %r14
133	movq	pt_regs_r15(%rax), %r15
134	pushq	pt_regs_flags(%rax)
135	popfq
136
137	/* Saved in save_processor_state. */
138	lgdt	saved_context_gdt_desc(%rax)
139
140	xorq	%rax, %rax
141
142	/* tell the hibernation core that we've just restored the memory */
143	movq	%rax, in_suspend(%rip)
144
145	ret
146ENDPROC(restore_registers)
147