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-rw-r--r--kernel/power/nvs.c136
1 files changed, 0 insertions, 136 deletions
diff --git a/kernel/power/nvs.c b/kernel/power/nvs.c
deleted file mode 100644
index 1836db60bbb6..000000000000
--- a/kernel/power/nvs.c
+++ /dev/null
@@ -1,136 +0,0 @@
1/*
2 * linux/kernel/power/hibernate_nvs.c - Routines for handling NVS memory
3 *
4 * Copyright (C) 2008,2009 Rafael J. Wysocki <rjw@sisk.pl>, Novell Inc.
5 *
6 * This file is released under the GPLv2.
7 */
8
9#include <linux/io.h>
10#include <linux/kernel.h>
11#include <linux/list.h>
12#include <linux/mm.h>
13#include <linux/slab.h>
14#include <linux/suspend.h>
15
16/*
17 * Platforms, like ACPI, may want us to save some memory used by them during
18 * suspend and to restore the contents of this memory during the subsequent
19 * resume. The code below implements a mechanism allowing us to do that.
20 */
21
22struct nvs_page {
23 unsigned long phys_start;
24 unsigned int size;
25 void *kaddr;
26 void *data;
27 struct list_head node;
28};
29
30static LIST_HEAD(nvs_list);
31
32/**
33 * suspend_nvs_register - register platform NVS memory region to save
34 * @start - physical address of the region
35 * @size - size of the region
36 *
37 * The NVS region need not be page-aligned (both ends) and we arrange
38 * things so that the data from page-aligned addresses in this region will
39 * be copied into separate RAM pages.
40 */
41int suspend_nvs_register(unsigned long start, unsigned long size)
42{
43 struct nvs_page *entry, *next;
44
45 while (size > 0) {
46 unsigned int nr_bytes;
47
48 entry = kzalloc(sizeof(struct nvs_page), GFP_KERNEL);
49 if (!entry)
50 goto Error;
51
52 list_add_tail(&entry->node, &nvs_list);
53 entry->phys_start = start;
54 nr_bytes = PAGE_SIZE - (start & ~PAGE_MASK);
55 entry->size = (size < nr_bytes) ? size : nr_bytes;
56
57 start += entry->size;
58 size -= entry->size;
59 }
60 return 0;
61
62 Error:
63 list_for_each_entry_safe(entry, next, &nvs_list, node) {
64 list_del(&entry->node);
65 kfree(entry);
66 }
67 return -ENOMEM;
68}
69
70/**
71 * suspend_nvs_free - free data pages allocated for saving NVS regions
72 */
73void suspend_nvs_free(void)
74{
75 struct nvs_page *entry;
76
77 list_for_each_entry(entry, &nvs_list, node)
78 if (entry->data) {
79 free_page((unsigned long)entry->data);
80 entry->data = NULL;
81 if (entry->kaddr) {
82 iounmap(entry->kaddr);
83 entry->kaddr = NULL;
84 }
85 }
86}
87
88/**
89 * suspend_nvs_alloc - allocate memory necessary for saving NVS regions
90 */
91int suspend_nvs_alloc(void)
92{
93 struct nvs_page *entry;
94
95 list_for_each_entry(entry, &nvs_list, node) {
96 entry->data = (void *)__get_free_page(GFP_KERNEL);
97 if (!entry->data) {
98 suspend_nvs_free();
99 return -ENOMEM;
100 }
101 }
102 return 0;
103}
104
105/**
106 * suspend_nvs_save - save NVS memory regions
107 */
108void suspend_nvs_save(void)
109{
110 struct nvs_page *entry;
111
112 printk(KERN_INFO "PM: Saving platform NVS memory\n");
113
114 list_for_each_entry(entry, &nvs_list, node)
115 if (entry->data) {
116 entry->kaddr = ioremap(entry->phys_start, entry->size);
117 memcpy(entry->data, entry->kaddr, entry->size);
118 }
119}
120
121/**
122 * suspend_nvs_restore - restore NVS memory regions
123 *
124 * This function is going to be called with interrupts disabled, so it
125 * cannot iounmap the virtual addresses used to access the NVS region.
126 */
127void suspend_nvs_restore(void)
128{
129 struct nvs_page *entry;
130
131 printk(KERN_INFO "PM: Restoring platform NVS memory\n");
132
133 list_for_each_entry(entry, &nvs_list, node)
134 if (entry->data)
135 memcpy(entry->kaddr, entry->data, entry->size);
136}