Commit | Line | Data |
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603fb42a SC |
1 | /* |
2 | * Hibernation support specific for ARM | |
3 | * | |
4 | * Derived from work on ARM hibernation support by: | |
5 | * | |
6 | * Ubuntu project, hibernation support for mach-dove | |
7 | * Copyright (C) 2010 Nokia Corporation (Hiroshi Doyu) | |
8 | * Copyright (C) 2010 Texas Instruments, Inc. (Teerth Reddy et al.) | |
9 | * https://lkml.org/lkml/2010/6/18/4 | |
10 | * https://lists.linux-foundation.org/pipermail/linux-pm/2010-June/027422.html | |
11 | * https://patchwork.kernel.org/patch/96442/ | |
12 | * | |
13 | * Copyright (C) 2006 Rafael J. Wysocki <rjw@sisk.pl> | |
14 | * | |
15 | * License terms: GNU General Public License (GPL) version 2 | |
16 | */ | |
17 | ||
18 | #include <linux/mm.h> | |
19 | #include <linux/suspend.h> | |
20 | #include <asm/system_misc.h> | |
21 | #include <asm/idmap.h> | |
22 | #include <asm/suspend.h> | |
23 | #include <asm/memory.h> | |
7f8998c7 | 24 | #include <asm/sections.h> |
603fb42a SC |
25 | |
26 | int pfn_is_nosave(unsigned long pfn) | |
27 | { | |
28 | unsigned long nosave_begin_pfn = virt_to_pfn(&__nosave_begin); | |
29 | unsigned long nosave_end_pfn = virt_to_pfn(&__nosave_end - 1); | |
30 | ||
31 | return (pfn >= nosave_begin_pfn) && (pfn <= nosave_end_pfn); | |
32 | } | |
33 | ||
34 | void notrace save_processor_state(void) | |
35 | { | |
36 | WARN_ON(num_online_cpus() != 1); | |
37 | local_fiq_disable(); | |
38 | } | |
39 | ||
40 | void notrace restore_processor_state(void) | |
41 | { | |
42 | local_fiq_enable(); | |
43 | } | |
44 | ||
45 | /* | |
46 | * Snapshot kernel memory and reset the system. | |
47 | * | |
48 | * swsusp_save() is executed in the suspend finisher so that the CPU | |
49 | * context pointer and memory are part of the saved image, which is | |
50 | * required by the resume kernel image to restart execution from | |
51 | * swsusp_arch_suspend(). | |
52 | * | |
53 | * soft_restart is not technically needed, but is used to get success | |
54 | * returned from cpu_suspend. | |
55 | * | |
56 | * When soft reboot completes, the hibernation snapshot is written out. | |
57 | */ | |
58 | static int notrace arch_save_image(unsigned long unused) | |
59 | { | |
60 | int ret; | |
61 | ||
62 | ret = swsusp_save(); | |
63 | if (ret == 0) | |
64 | soft_restart(virt_to_phys(cpu_resume)); | |
65 | return ret; | |
66 | } | |
67 | ||
68 | /* | |
69 | * Save the current CPU state before suspend / poweroff. | |
70 | */ | |
71 | int notrace swsusp_arch_suspend(void) | |
72 | { | |
73 | return cpu_suspend(0, arch_save_image); | |
74 | } | |
75 | ||
76 | /* | |
77 | * Restore page contents for physical pages that were in use during loading | |
78 | * hibernation image. Switch to idmap_pgd so the physical page tables | |
79 | * are overwritten with the same contents. | |
80 | */ | |
81 | static void notrace arch_restore_image(void *unused) | |
82 | { | |
83 | struct pbe *pbe; | |
84 | ||
85 | cpu_switch_mm(idmap_pgd, &init_mm); | |
86 | for (pbe = restore_pblist; pbe; pbe = pbe->next) | |
87 | copy_page(pbe->orig_address, pbe->address); | |
88 | ||
89 | soft_restart(virt_to_phys(cpu_resume)); | |
90 | } | |
91 | ||
92 | static u64 resume_stack[PAGE_SIZE/2/sizeof(u64)] __nosavedata; | |
93 | ||
94 | /* | |
95 | * Resume from the hibernation image. | |
96 | * Due to the kernel heap / data restore, stack contents change underneath | |
97 | * and that would make function calls impossible; switch to a temporary | |
98 | * stack within the nosave region to avoid that problem. | |
99 | */ | |
100 | int swsusp_arch_resume(void) | |
101 | { | |
102 | extern void call_with_stack(void (*fn)(void *), void *arg, void *sp); | |
103 | call_with_stack(arch_restore_image, 0, | |
104 | resume_stack + ARRAY_SIZE(resume_stack)); | |
105 | return 0; | |
106 | } |