Thomas Gleixner | 55716d2 | 2019-06-01 10:08:42 +0200 | [diff] [blame] | 1 | // SPDX-License-Identifier: GPL-2.0-only |
Cornelia Huck | fce2b111 | 2009-06-10 01:28:19 +0200 | [diff] [blame] | 2 | /* |
Rafael J. Wysocki | d146df1 | 2011-01-07 01:44:28 +0100 | [diff] [blame] | 3 | * nvs.c - Routines for saving and restoring ACPI NVS memory region |
Cornelia Huck | fce2b111 | 2009-06-10 01:28:19 +0200 | [diff] [blame] | 4 | * |
Rafael J. Wysocki | d146df1 | 2011-01-07 01:44:28 +0100 | [diff] [blame] | 5 | * Copyright (C) 2008-2011 Rafael J. Wysocki <rjw@sisk.pl>, Novell Inc. |
Cornelia Huck | fce2b111 | 2009-06-10 01:28:19 +0200 | [diff] [blame] | 6 | */ |
| 7 | |
Hanjun Guo | 4f59927 | 2021-06-02 16:54:28 +0800 | [diff] [blame] | 8 | #define pr_fmt(fmt) "ACPI: PM: " fmt |
| 9 | |
Cornelia Huck | fce2b111 | 2009-06-10 01:28:19 +0200 | [diff] [blame] | 10 | #include <linux/io.h> |
| 11 | #include <linux/kernel.h> |
| 12 | #include <linux/list.h> |
| 13 | #include <linux/mm.h> |
Tejun Heo | 5a0e3ad | 2010-03-24 17:04:11 +0900 | [diff] [blame] | 14 | #include <linux/slab.h> |
Rafael J. Wysocki | d146df1 | 2011-01-07 01:44:28 +0100 | [diff] [blame] | 15 | #include <linux/acpi.h> |
Cornelia Huck | fce2b111 | 2009-06-10 01:28:19 +0200 | [diff] [blame] | 16 | |
Rashika | 679c581 | 2013-12-17 14:45:00 +0530 | [diff] [blame] | 17 | #include "internal.h" |
| 18 | |
Huang Ying | b54ac6d | 2011-12-08 11:25:49 +0800 | [diff] [blame] | 19 | /* ACPI NVS regions, APEI may use it */ |
| 20 | |
| 21 | struct nvs_region { |
| 22 | __u64 phys_start; |
| 23 | __u64 size; |
| 24 | struct list_head node; |
| 25 | }; |
| 26 | |
| 27 | static LIST_HEAD(nvs_region_list); |
| 28 | |
| 29 | #ifdef CONFIG_ACPI_SLEEP |
| 30 | static int suspend_nvs_register(unsigned long start, unsigned long size); |
| 31 | #else |
| 32 | static inline int suspend_nvs_register(unsigned long a, unsigned long b) |
| 33 | { |
| 34 | return 0; |
| 35 | } |
| 36 | #endif |
| 37 | |
| 38 | int acpi_nvs_register(__u64 start, __u64 size) |
| 39 | { |
| 40 | struct nvs_region *region; |
| 41 | |
| 42 | region = kmalloc(sizeof(*region), GFP_KERNEL); |
| 43 | if (!region) |
| 44 | return -ENOMEM; |
| 45 | region->phys_start = start; |
| 46 | region->size = size; |
| 47 | list_add_tail(®ion->node, &nvs_region_list); |
| 48 | |
| 49 | return suspend_nvs_register(start, size); |
| 50 | } |
| 51 | |
| 52 | int acpi_nvs_for_each_region(int (*func)(__u64 start, __u64 size, void *data), |
| 53 | void *data) |
| 54 | { |
| 55 | int rc; |
| 56 | struct nvs_region *region; |
| 57 | |
| 58 | list_for_each_entry(region, &nvs_region_list, node) { |
| 59 | rc = func(region->phys_start, region->size, data); |
| 60 | if (rc) |
| 61 | return rc; |
| 62 | } |
| 63 | |
| 64 | return 0; |
| 65 | } |
| 66 | |
| 67 | |
| 68 | #ifdef CONFIG_ACPI_SLEEP |
Cornelia Huck | fce2b111 | 2009-06-10 01:28:19 +0200 | [diff] [blame] | 69 | /* |
| 70 | * Platforms, like ACPI, may want us to save some memory used by them during |
Matthew Garrett | dd4c4f1 | 2010-05-28 16:32:14 -0400 | [diff] [blame] | 71 | * suspend and to restore the contents of this memory during the subsequent |
Cornelia Huck | fce2b111 | 2009-06-10 01:28:19 +0200 | [diff] [blame] | 72 | * resume. The code below implements a mechanism allowing us to do that. |
| 73 | */ |
| 74 | |
| 75 | struct nvs_page { |
| 76 | unsigned long phys_start; |
| 77 | unsigned int size; |
| 78 | void *kaddr; |
| 79 | void *data; |
Rafael J. Wysocki | bb45e39 | 2011-02-08 23:38:38 +0100 | [diff] [blame] | 80 | bool unmap; |
Cornelia Huck | fce2b111 | 2009-06-10 01:28:19 +0200 | [diff] [blame] | 81 | struct list_head node; |
| 82 | }; |
| 83 | |
| 84 | static LIST_HEAD(nvs_list); |
| 85 | |
| 86 | /** |
Baokun Li | 120f4aa | 2021-06-15 15:43:17 +0800 | [diff] [blame] | 87 | * suspend_nvs_register - register platform NVS memory region to save |
| 88 | * @start: Physical address of the region. |
| 89 | * @size: Size of the region. |
Cornelia Huck | fce2b111 | 2009-06-10 01:28:19 +0200 | [diff] [blame] | 90 | * |
Baokun Li | 120f4aa | 2021-06-15 15:43:17 +0800 | [diff] [blame] | 91 | * The NVS region need not be page-aligned (both ends) and we arrange |
| 92 | * things so that the data from page-aligned addresses in this region will |
| 93 | * be copied into separate RAM pages. |
Cornelia Huck | fce2b111 | 2009-06-10 01:28:19 +0200 | [diff] [blame] | 94 | */ |
Huang Ying | b54ac6d | 2011-12-08 11:25:49 +0800 | [diff] [blame] | 95 | static int suspend_nvs_register(unsigned long start, unsigned long size) |
Cornelia Huck | fce2b111 | 2009-06-10 01:28:19 +0200 | [diff] [blame] | 96 | { |
| 97 | struct nvs_page *entry, *next; |
| 98 | |
Hanjun Guo | 4f59927 | 2021-06-02 16:54:28 +0800 | [diff] [blame] | 99 | pr_info("Registering ACPI NVS region [mem %#010lx-%#010lx] (%ld bytes)\n", |
Bjorn Helgaas | c6436f5a | 2012-02-13 17:04:43 -0700 | [diff] [blame] | 100 | start, start + size - 1, size); |
Rafael J. Wysocki | bb45e39 | 2011-02-08 23:38:38 +0100 | [diff] [blame] | 101 | |
Cornelia Huck | fce2b111 | 2009-06-10 01:28:19 +0200 | [diff] [blame] | 102 | while (size > 0) { |
| 103 | unsigned int nr_bytes; |
| 104 | |
| 105 | entry = kzalloc(sizeof(struct nvs_page), GFP_KERNEL); |
| 106 | if (!entry) |
| 107 | goto Error; |
| 108 | |
| 109 | list_add_tail(&entry->node, &nvs_list); |
| 110 | entry->phys_start = start; |
| 111 | nr_bytes = PAGE_SIZE - (start & ~PAGE_MASK); |
| 112 | entry->size = (size < nr_bytes) ? size : nr_bytes; |
| 113 | |
| 114 | start += entry->size; |
| 115 | size -= entry->size; |
| 116 | } |
| 117 | return 0; |
| 118 | |
| 119 | Error: |
| 120 | list_for_each_entry_safe(entry, next, &nvs_list, node) { |
| 121 | list_del(&entry->node); |
| 122 | kfree(entry); |
| 123 | } |
| 124 | return -ENOMEM; |
| 125 | } |
| 126 | |
| 127 | /** |
Baokun Li | 120f4aa | 2021-06-15 15:43:17 +0800 | [diff] [blame] | 128 | * suspend_nvs_free - free data pages allocated for saving NVS regions |
Cornelia Huck | fce2b111 | 2009-06-10 01:28:19 +0200 | [diff] [blame] | 129 | */ |
Matthew Garrett | dd4c4f1 | 2010-05-28 16:32:14 -0400 | [diff] [blame] | 130 | void suspend_nvs_free(void) |
Cornelia Huck | fce2b111 | 2009-06-10 01:28:19 +0200 | [diff] [blame] | 131 | { |
| 132 | struct nvs_page *entry; |
| 133 | |
| 134 | list_for_each_entry(entry, &nvs_list, node) |
| 135 | if (entry->data) { |
| 136 | free_page((unsigned long)entry->data); |
| 137 | entry->data = NULL; |
| 138 | if (entry->kaddr) { |
Rafael J. Wysocki | bb45e39 | 2011-02-08 23:38:38 +0100 | [diff] [blame] | 139 | if (entry->unmap) { |
| 140 | iounmap(entry->kaddr); |
| 141 | entry->unmap = false; |
| 142 | } else { |
Lv Zheng | a238317 | 2014-05-20 15:39:41 +0800 | [diff] [blame] | 143 | acpi_os_unmap_iomem(entry->kaddr, |
| 144 | entry->size); |
Rafael J. Wysocki | bb45e39 | 2011-02-08 23:38:38 +0100 | [diff] [blame] | 145 | } |
Cornelia Huck | fce2b111 | 2009-06-10 01:28:19 +0200 | [diff] [blame] | 146 | entry->kaddr = NULL; |
| 147 | } |
| 148 | } |
| 149 | } |
| 150 | |
| 151 | /** |
Baokun Li | 120f4aa | 2021-06-15 15:43:17 +0800 | [diff] [blame] | 152 | * suspend_nvs_alloc - allocate memory necessary for saving NVS regions |
Cornelia Huck | fce2b111 | 2009-06-10 01:28:19 +0200 | [diff] [blame] | 153 | */ |
Matthew Garrett | dd4c4f1 | 2010-05-28 16:32:14 -0400 | [diff] [blame] | 154 | int suspend_nvs_alloc(void) |
Cornelia Huck | fce2b111 | 2009-06-10 01:28:19 +0200 | [diff] [blame] | 155 | { |
| 156 | struct nvs_page *entry; |
| 157 | |
| 158 | list_for_each_entry(entry, &nvs_list, node) { |
| 159 | entry->data = (void *)__get_free_page(GFP_KERNEL); |
| 160 | if (!entry->data) { |
Matthew Garrett | dd4c4f1 | 2010-05-28 16:32:14 -0400 | [diff] [blame] | 161 | suspend_nvs_free(); |
Cornelia Huck | fce2b111 | 2009-06-10 01:28:19 +0200 | [diff] [blame] | 162 | return -ENOMEM; |
| 163 | } |
| 164 | } |
| 165 | return 0; |
| 166 | } |
| 167 | |
| 168 | /** |
Baokun Li | 120f4aa | 2021-06-15 15:43:17 +0800 | [diff] [blame] | 169 | * suspend_nvs_save - save NVS memory regions |
Cornelia Huck | fce2b111 | 2009-06-10 01:28:19 +0200 | [diff] [blame] | 170 | */ |
Jiri Slaby | 26fcaf6 | 2011-01-07 01:42:31 +0100 | [diff] [blame] | 171 | int suspend_nvs_save(void) |
Cornelia Huck | fce2b111 | 2009-06-10 01:28:19 +0200 | [diff] [blame] | 172 | { |
| 173 | struct nvs_page *entry; |
| 174 | |
Hanjun Guo | 4f59927 | 2021-06-02 16:54:28 +0800 | [diff] [blame] | 175 | pr_info("Saving platform NVS memory\n"); |
Cornelia Huck | fce2b111 | 2009-06-10 01:28:19 +0200 | [diff] [blame] | 176 | |
| 177 | list_for_each_entry(entry, &nvs_list, node) |
| 178 | if (entry->data) { |
Rafael J. Wysocki | bb45e39 | 2011-02-08 23:38:38 +0100 | [diff] [blame] | 179 | unsigned long phys = entry->phys_start; |
| 180 | unsigned int size = entry->size; |
| 181 | |
| 182 | entry->kaddr = acpi_os_get_iomem(phys, size); |
| 183 | if (!entry->kaddr) { |
| 184 | entry->kaddr = acpi_os_ioremap(phys, size); |
| 185 | entry->unmap = !!entry->kaddr; |
| 186 | } |
Jiri Slaby | 26fcaf6 | 2011-01-07 01:42:31 +0100 | [diff] [blame] | 187 | if (!entry->kaddr) { |
| 188 | suspend_nvs_free(); |
| 189 | return -ENOMEM; |
| 190 | } |
Cornelia Huck | fce2b111 | 2009-06-10 01:28:19 +0200 | [diff] [blame] | 191 | memcpy(entry->data, entry->kaddr, entry->size); |
| 192 | } |
Jiri Slaby | 26fcaf6 | 2011-01-07 01:42:31 +0100 | [diff] [blame] | 193 | |
| 194 | return 0; |
Cornelia Huck | fce2b111 | 2009-06-10 01:28:19 +0200 | [diff] [blame] | 195 | } |
| 196 | |
| 197 | /** |
Baokun Li | 120f4aa | 2021-06-15 15:43:17 +0800 | [diff] [blame] | 198 | * suspend_nvs_restore - restore NVS memory regions |
Cornelia Huck | fce2b111 | 2009-06-10 01:28:19 +0200 | [diff] [blame] | 199 | * |
Baokun Li | 120f4aa | 2021-06-15 15:43:17 +0800 | [diff] [blame] | 200 | * This function is going to be called with interrupts disabled, so it |
| 201 | * cannot iounmap the virtual addresses used to access the NVS region. |
Cornelia Huck | fce2b111 | 2009-06-10 01:28:19 +0200 | [diff] [blame] | 202 | */ |
Matthew Garrett | dd4c4f1 | 2010-05-28 16:32:14 -0400 | [diff] [blame] | 203 | void suspend_nvs_restore(void) |
Cornelia Huck | fce2b111 | 2009-06-10 01:28:19 +0200 | [diff] [blame] | 204 | { |
| 205 | struct nvs_page *entry; |
| 206 | |
Hanjun Guo | 4f59927 | 2021-06-02 16:54:28 +0800 | [diff] [blame] | 207 | pr_info("Restoring platform NVS memory\n"); |
Cornelia Huck | fce2b111 | 2009-06-10 01:28:19 +0200 | [diff] [blame] | 208 | |
| 209 | list_for_each_entry(entry, &nvs_list, node) |
| 210 | if (entry->data) |
| 211 | memcpy(entry->kaddr, entry->data, entry->size); |
| 212 | } |
Huang Ying | b54ac6d | 2011-12-08 11:25:49 +0800 | [diff] [blame] | 213 | #endif |