1/* SPDX-License-Identifier: GPL-2.0-only */
2/*
3 * Hibernation support for x86-64
4 *
5 * Copyright 2007 Rafael J. Wysocki <rjw@sisk.pl>
6 * Copyright 2005 Andi Kleen <ak@suse.de>
7 * Copyright 2004 Pavel Machek <pavel@suse.cz>
8 *
9 * swsusp_arch_resume must not use any stack or any nonlocal variables while
10 * copying pages:
11 *
12 * Its rewriting one kernel image with another. What is stack in "old"
13 * image could very well be data page in "new" image, and overwriting
14 * your own stack under you is bad idea.
15 */
16
17 .text
18#include <linux/linkage.h>
19#include <asm/segment.h>
20#include <asm/page_types.h>
21#include <asm/asm-offsets.h>
22#include <asm/processor-flags.h>
23#include <asm/frame.h>
24#include <asm/nospec-branch.h>
25
26 /* code below belongs to the image kernel */
27 .align PAGE_SIZE
28SYM_FUNC_START(restore_registers)
29 /* go back to the original page tables */
30 movq %r9, %cr3
31
32 /* Flush TLB, including "global" things (vmalloc) */
33 movq mmu_cr4_features(%rip), %rax
34 movq %rax, %rdx
35 andq $~(X86_CR4_PGE), %rdx
36 movq %rdx, %cr4; # turn off PGE
37 movq %cr3, %rcx; # flush TLB
38 movq %rcx, %cr3
39 movq %rax, %cr4; # turn PGE back on
40
41 /* We don't restore %rax, it must be 0 anyway */
42 movq $saved_context, %rax
43 movq pt_regs_sp(%rax), %rsp
44 movq pt_regs_bp(%rax), %rbp
45 movq pt_regs_si(%rax), %rsi
46 movq pt_regs_di(%rax), %rdi
47 movq pt_regs_bx(%rax), %rbx
48 movq pt_regs_cx(%rax), %rcx
49 movq pt_regs_dx(%rax), %rdx
50 movq pt_regs_r8(%rax), %r8
51 movq pt_regs_r9(%rax), %r9
52 movq pt_regs_r10(%rax), %r10
53 movq pt_regs_r11(%rax), %r11
54 movq pt_regs_r12(%rax), %r12
55 movq pt_regs_r13(%rax), %r13
56 movq pt_regs_r14(%rax), %r14
57 movq pt_regs_r15(%rax), %r15
58 pushq pt_regs_flags(%rax)
59 popfq
60
61 /* Saved in save_processor_state. */
62 lgdt saved_context_gdt_desc(%rax)
63
64 xorl %eax, %eax
65
66 /* tell the hibernation core that we've just restored the memory */
67 movq %rax, in_suspend(%rip)
68
69 RET
70SYM_FUNC_END(restore_registers)
71
72SYM_FUNC_START(swsusp_arch_suspend)
73 movq $saved_context, %rax
74 movq %rsp, pt_regs_sp(%rax)
75 movq %rbp, pt_regs_bp(%rax)
76 movq %rsi, pt_regs_si(%rax)
77 movq %rdi, pt_regs_di(%rax)
78 movq %rbx, pt_regs_bx(%rax)
79 movq %rcx, pt_regs_cx(%rax)
80 movq %rdx, pt_regs_dx(%rax)
81 movq %r8, pt_regs_r8(%rax)
82 movq %r9, pt_regs_r9(%rax)
83 movq %r10, pt_regs_r10(%rax)
84 movq %r11, pt_regs_r11(%rax)
85 movq %r12, pt_regs_r12(%rax)
86 movq %r13, pt_regs_r13(%rax)
87 movq %r14, pt_regs_r14(%rax)
88 movq %r15, pt_regs_r15(%rax)
89 pushfq
90 popq pt_regs_flags(%rax)
91
92 /* save cr3 */
93 movq %cr3, %rax
94 movq %rax, restore_cr3(%rip)
95
96 FRAME_BEGIN
97 call swsusp_save
98 FRAME_END
99 RET
100SYM_FUNC_END(swsusp_arch_suspend)
101
102SYM_FUNC_START(restore_image)
103 /* prepare to jump to the image kernel */
104 movq restore_jump_address(%rip), %r8
105 movq restore_cr3(%rip), %r9
106
107 /* prepare to switch to temporary page tables */
108 movq temp_pgt(%rip), %rax
109 movq mmu_cr4_features(%rip), %rbx
110
111 /* prepare to copy image data to their original locations */
112 movq restore_pblist(%rip), %rdx
113
114 /* jump to relocated restore code */
115 movq relocated_restore_code(%rip), %rcx
116 ANNOTATE_RETPOLINE_SAFE
117 jmpq *%rcx
118SYM_FUNC_END(restore_image)
119
120 /* code below has been relocated to a safe page */
121SYM_FUNC_START(core_restore_code)
122 /* switch to temporary page tables */
123 movq %rax, %cr3
124 /* flush TLB */
125 movq %rbx, %rcx
126 andq $~(X86_CR4_PGE), %rcx
127 movq %rcx, %cr4; # turn off PGE
128 movq %cr3, %rcx; # flush TLB
129 movq %rcx, %cr3;
130 movq %rbx, %cr4; # turn PGE back on
131.Lloop:
132 testq %rdx, %rdx
133 jz .Ldone
134
135 /* get addresses from the pbe and copy the page */
136 movq pbe_address(%rdx), %rsi
137 movq pbe_orig_address(%rdx), %rdi
138 movq $(PAGE_SIZE >> 3), %rcx
139 rep
140 movsq
141
142 /* progress to the next pbe */
143 movq pbe_next(%rdx), %rdx
144 jmp .Lloop
145
146.Ldone:
147 /* jump to the restore_registers address from the image header */
148 ANNOTATE_RETPOLINE_SAFE
149 jmpq *%r8
150SYM_FUNC_END(core_restore_code)
151

source code of linux/arch/x86/power/hibernate_asm_64.S