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Bernhard Walle69ac9cd2008-06-27 13:12:54 +02001/*
2 * linux/drivers/firmware/memmap.c
3 * Copyright (C) 2008 SUSE LINUX Products GmbH
Bernhard Walle97bef7d2009-02-18 14:48:40 -08004 * by Bernhard Walle <bernhard.walle@gmx.de>
Bernhard Walle69ac9cd2008-06-27 13:12:54 +02005 *
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License v2.0 as published by
8 * the Free Software Foundation
9 *
10 * This program is distributed in the hope that it will be useful,
11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13 * GNU General Public License for more details.
14 *
15 */
16
17#include <linux/string.h>
18#include <linux/firmware-map.h>
19#include <linux/kernel.h>
20#include <linux/module.h>
21#include <linux/types.h>
22#include <linux/bootmem.h>
Tejun Heo5a0e3ad2010-03-24 17:04:11 +090023#include <linux/slab.h>
Bernhard Walle69ac9cd2008-06-27 13:12:54 +020024
25/*
26 * Data types ------------------------------------------------------------------
27 */
28
29/*
30 * Firmware map entry. Because firmware memory maps are flat and not
31 * hierarchical, it's ok to organise them in a linked list. No parent
32 * information is necessary as for the resource tree.
33 */
34struct firmware_map_entry {
Yinghai Lu3b0fde02009-06-16 15:31:16 -070035 /*
36 * start and end must be u64 rather than resource_size_t, because e820
37 * resources can lie at addresses above 4G.
38 */
39 u64 start; /* start of the memory range */
40 u64 end; /* end of the memory range (incl.) */
Bernhard Walle69ac9cd2008-06-27 13:12:54 +020041 const char *type; /* type of the memory range */
42 struct list_head list; /* entry for the linked list */
43 struct kobject kobj; /* kobject for each entry */
44};
45
46/*
47 * Forward declarations --------------------------------------------------------
48 */
49static ssize_t memmap_attr_show(struct kobject *kobj,
50 struct attribute *attr, char *buf);
51static ssize_t start_show(struct firmware_map_entry *entry, char *buf);
52static ssize_t end_show(struct firmware_map_entry *entry, char *buf);
53static ssize_t type_show(struct firmware_map_entry *entry, char *buf);
54
55/*
56 * Static data -----------------------------------------------------------------
57 */
58
59struct memmap_attribute {
60 struct attribute attr;
61 ssize_t (*show)(struct firmware_map_entry *entry, char *buf);
62};
63
Roel Kluinda2bdf92009-01-07 18:09:15 -080064static struct memmap_attribute memmap_start_attr = __ATTR_RO(start);
65static struct memmap_attribute memmap_end_attr = __ATTR_RO(end);
66static struct memmap_attribute memmap_type_attr = __ATTR_RO(type);
Bernhard Walle69ac9cd2008-06-27 13:12:54 +020067
68/*
69 * These are default attributes that are added for every memmap entry.
70 */
71static struct attribute *def_attrs[] = {
72 &memmap_start_attr.attr,
73 &memmap_end_attr.attr,
74 &memmap_type_attr.attr,
75 NULL
76};
77
Emese Revfy52cf25d2010-01-19 02:58:23 +010078static const struct sysfs_ops memmap_attr_ops = {
Bernhard Walle69ac9cd2008-06-27 13:12:54 +020079 .show = memmap_attr_show,
80};
81
82static struct kobj_type memmap_ktype = {
83 .sysfs_ops = &memmap_attr_ops,
84 .default_attrs = def_attrs,
85};
86
87/*
88 * Registration functions ------------------------------------------------------
89 */
90
91/*
Bernhard Walle31bad922008-08-12 15:09:14 -070092 * Firmware memory map entries. No locking is needed because the
93 * firmware_map_add() and firmware_map_add_early() functions are called
94 * in firmware initialisation code in one single thread of execution.
Bernhard Walle69ac9cd2008-06-27 13:12:54 +020095 */
96static LIST_HEAD(map_entries);
97
98/**
Bernhard Walle31bad922008-08-12 15:09:14 -070099 * firmware_map_add_entry() - Does the real work to add a firmware memmap entry.
Bernhard Walle69ac9cd2008-06-27 13:12:54 +0200100 * @start: Start of the memory range.
Yasuaki Ishimatsu4ed940d2012-07-30 14:41:13 -0700101 * @end: End of the memory range (exclusive).
Bernhard Walle69ac9cd2008-06-27 13:12:54 +0200102 * @type: Type of the memory range.
103 * @entry: Pre-allocated (either kmalloc() or bootmem allocator), uninitialised
104 * entry.
Bernhard Walle31bad922008-08-12 15:09:14 -0700105 *
106 * Common implementation of firmware_map_add() and firmware_map_add_early()
107 * which expects a pre-allocated struct firmware_map_entry.
108 **/
Yinghai Lu3b0fde02009-06-16 15:31:16 -0700109static int firmware_map_add_entry(u64 start, u64 end,
Bernhard Walle69ac9cd2008-06-27 13:12:54 +0200110 const char *type,
111 struct firmware_map_entry *entry)
112{
113 BUG_ON(start > end);
114
115 entry->start = start;
Yasuaki Ishimatsu4ed940d2012-07-30 14:41:13 -0700116 entry->end = end - 1;
Bernhard Walle69ac9cd2008-06-27 13:12:54 +0200117 entry->type = type;
118 INIT_LIST_HEAD(&entry->list);
119 kobject_init(&entry->kobj, &memmap_ktype);
120
121 list_add_tail(&entry->list, &map_entries);
122
123 return 0;
124}
125
akpm@linux-foundation.orgd96ae532010-03-05 13:41:58 -0800126/*
127 * Add memmap entry on sysfs
128 */
129static int add_sysfs_fw_map_entry(struct firmware_map_entry *entry)
130{
131 static int map_entries_nr;
132 static struct kset *mmap_kset;
133
134 if (!mmap_kset) {
135 mmap_kset = kset_create_and_add("memmap", NULL, firmware_kobj);
136 if (!mmap_kset)
137 return -ENOMEM;
138 }
139
140 entry->kobj.kset = mmap_kset;
141 if (kobject_add(&entry->kobj, NULL, "%d", map_entries_nr++))
142 kobject_put(&entry->kobj);
143
144 return 0;
145}
146
Bernhard Walle31bad922008-08-12 15:09:14 -0700147/**
akpm@linux-foundation.orgd96ae532010-03-05 13:41:58 -0800148 * firmware_map_add_hotplug() - Adds a firmware mapping entry when we do
149 * memory hotplug.
Bernhard Walle31bad922008-08-12 15:09:14 -0700150 * @start: Start of the memory range.
Yasuaki Ishimatsu4ed940d2012-07-30 14:41:13 -0700151 * @end: End of the memory range (exclusive)
Bernhard Walle31bad922008-08-12 15:09:14 -0700152 * @type: Type of the memory range.
153 *
akpm@linux-foundation.orgd96ae532010-03-05 13:41:58 -0800154 * Adds a firmware mapping entry. This function is for memory hotplug, it is
155 * similar to function firmware_map_add_early(). The only difference is that
156 * it will create the syfs entry dynamically.
Bernhard Walle31bad922008-08-12 15:09:14 -0700157 *
158 * Returns 0 on success, or -ENOMEM if no memory could be allocated.
159 **/
akpm@linux-foundation.orgd96ae532010-03-05 13:41:58 -0800160int __meminit firmware_map_add_hotplug(u64 start, u64 end, const char *type)
Bernhard Walle69ac9cd2008-06-27 13:12:54 +0200161{
162 struct firmware_map_entry *entry;
163
akpm@linux-foundation.orgd96ae532010-03-05 13:41:58 -0800164 entry = kzalloc(sizeof(struct firmware_map_entry), GFP_ATOMIC);
Bernhard Walle69ac9cd2008-06-27 13:12:54 +0200165 if (!entry)
166 return -ENOMEM;
167
akpm@linux-foundation.orgd96ae532010-03-05 13:41:58 -0800168 firmware_map_add_entry(start, end, type, entry);
169 /* create the memmap entry */
170 add_sysfs_fw_map_entry(entry);
171
172 return 0;
Bernhard Walle69ac9cd2008-06-27 13:12:54 +0200173}
174
Bernhard Walle31bad922008-08-12 15:09:14 -0700175/**
176 * firmware_map_add_early() - Adds a firmware mapping entry.
177 * @start: Start of the memory range.
Yasuaki Ishimatsu4ed940d2012-07-30 14:41:13 -0700178 * @end: End of the memory range.
Bernhard Walle31bad922008-08-12 15:09:14 -0700179 * @type: Type of the memory range.
180 *
181 * Adds a firmware mapping entry. This function uses the bootmem allocator
akpm@linux-foundation.orgd96ae532010-03-05 13:41:58 -0800182 * for memory allocation.
Bernhard Walle31bad922008-08-12 15:09:14 -0700183 *
184 * That function must be called before late_initcall.
185 *
186 * Returns 0 on success, or -ENOMEM if no memory could be allocated.
187 **/
Yinghai Lu3b0fde02009-06-16 15:31:16 -0700188int __init firmware_map_add_early(u64 start, u64 end, const char *type)
Bernhard Walle69ac9cd2008-06-27 13:12:54 +0200189{
190 struct firmware_map_entry *entry;
191
Jan Beulich3c1596e2009-09-21 17:03:06 -0700192 entry = alloc_bootmem(sizeof(struct firmware_map_entry));
Bernhard Walle31bad922008-08-12 15:09:14 -0700193 if (WARN_ON(!entry))
Bernhard Walle69ac9cd2008-06-27 13:12:54 +0200194 return -ENOMEM;
195
196 return firmware_map_add_entry(start, end, type, entry);
197}
198
199/*
200 * Sysfs functions -------------------------------------------------------------
201 */
202
203static ssize_t start_show(struct firmware_map_entry *entry, char *buf)
204{
Randy Dunlap78681ac2008-07-26 15:22:28 -0700205 return snprintf(buf, PAGE_SIZE, "0x%llx\n",
206 (unsigned long long)entry->start);
Bernhard Walle69ac9cd2008-06-27 13:12:54 +0200207}
208
209static ssize_t end_show(struct firmware_map_entry *entry, char *buf)
210{
Randy Dunlap78681ac2008-07-26 15:22:28 -0700211 return snprintf(buf, PAGE_SIZE, "0x%llx\n",
212 (unsigned long long)entry->end);
Bernhard Walle69ac9cd2008-06-27 13:12:54 +0200213}
214
215static ssize_t type_show(struct firmware_map_entry *entry, char *buf)
216{
217 return snprintf(buf, PAGE_SIZE, "%s\n", entry->type);
218}
219
220#define to_memmap_attr(_attr) container_of(_attr, struct memmap_attribute, attr)
221#define to_memmap_entry(obj) container_of(obj, struct firmware_map_entry, kobj)
222
223static ssize_t memmap_attr_show(struct kobject *kobj,
224 struct attribute *attr, char *buf)
225{
226 struct firmware_map_entry *entry = to_memmap_entry(kobj);
227 struct memmap_attribute *memmap_attr = to_memmap_attr(attr);
228
229 return memmap_attr->show(entry, buf);
230}
231
232/*
233 * Initialises stuff and adds the entries in the map_entries list to
234 * sysfs. Important is that firmware_map_add() and firmware_map_add_early()
Bernhard Walle31bad922008-08-12 15:09:14 -0700235 * must be called before late_initcall. That's just because that function
236 * is called as late_initcall() function, which means that if you call
237 * firmware_map_add() or firmware_map_add_early() afterwards, the entries
238 * are not added to sysfs.
Bernhard Walle69ac9cd2008-06-27 13:12:54 +0200239 */
Fengguang Wubac71692012-10-19 13:56:55 -0700240static int __init firmware_memmap_init(void)
Bernhard Walle69ac9cd2008-06-27 13:12:54 +0200241{
Bernhard Walle69ac9cd2008-06-27 13:12:54 +0200242 struct firmware_map_entry *entry;
Bernhard Walle69ac9cd2008-06-27 13:12:54 +0200243
akpm@linux-foundation.orgd96ae532010-03-05 13:41:58 -0800244 list_for_each_entry(entry, &map_entries, list)
245 add_sysfs_fw_map_entry(entry);
Bernhard Walle69ac9cd2008-06-27 13:12:54 +0200246
247 return 0;
248}
Fengguang Wubac71692012-10-19 13:56:55 -0700249late_initcall(firmware_memmap_init);
Bernhard Walle69ac9cd2008-06-27 13:12:54 +0200250