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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>
23
24/*
25 * Data types ------------------------------------------------------------------
26 */
27
28/*
29 * Firmware map entry. Because firmware memory maps are flat and not
30 * hierarchical, it's ok to organise them in a linked list. No parent
31 * information is necessary as for the resource tree.
32 */
33struct firmware_map_entry {
34 resource_size_t start; /* start of the memory range */
35 resource_size_t end; /* end of the memory range (incl.) */
36 const char *type; /* type of the memory range */
37 struct list_head list; /* entry for the linked list */
38 struct kobject kobj; /* kobject for each entry */
39};
40
41/*
42 * Forward declarations --------------------------------------------------------
43 */
44static ssize_t memmap_attr_show(struct kobject *kobj,
45 struct attribute *attr, char *buf);
46static ssize_t start_show(struct firmware_map_entry *entry, char *buf);
47static ssize_t end_show(struct firmware_map_entry *entry, char *buf);
48static ssize_t type_show(struct firmware_map_entry *entry, char *buf);
49
50/*
51 * Static data -----------------------------------------------------------------
52 */
53
54struct memmap_attribute {
55 struct attribute attr;
56 ssize_t (*show)(struct firmware_map_entry *entry, char *buf);
57};
58
Roel Kluinda2bdf92009-01-07 18:09:15 -080059static struct memmap_attribute memmap_start_attr = __ATTR_RO(start);
60static struct memmap_attribute memmap_end_attr = __ATTR_RO(end);
61static struct memmap_attribute memmap_type_attr = __ATTR_RO(type);
Bernhard Walle69ac9cd2008-06-27 13:12:54 +020062
63/*
64 * These are default attributes that are added for every memmap entry.
65 */
66static struct attribute *def_attrs[] = {
67 &memmap_start_attr.attr,
68 &memmap_end_attr.attr,
69 &memmap_type_attr.attr,
70 NULL
71};
72
73static struct sysfs_ops memmap_attr_ops = {
74 .show = memmap_attr_show,
75};
76
77static struct kobj_type memmap_ktype = {
78 .sysfs_ops = &memmap_attr_ops,
79 .default_attrs = def_attrs,
80};
81
82/*
83 * Registration functions ------------------------------------------------------
84 */
85
86/*
Bernhard Walle31bad922008-08-12 15:09:14 -070087 * Firmware memory map entries. No locking is needed because the
88 * firmware_map_add() and firmware_map_add_early() functions are called
89 * in firmware initialisation code in one single thread of execution.
Bernhard Walle69ac9cd2008-06-27 13:12:54 +020090 */
91static LIST_HEAD(map_entries);
92
93/**
Bernhard Walle31bad922008-08-12 15:09:14 -070094 * firmware_map_add_entry() - Does the real work to add a firmware memmap entry.
Bernhard Walle69ac9cd2008-06-27 13:12:54 +020095 * @start: Start of the memory range.
96 * @end: End of the memory range (inclusive).
97 * @type: Type of the memory range.
98 * @entry: Pre-allocated (either kmalloc() or bootmem allocator), uninitialised
99 * entry.
Bernhard Walle31bad922008-08-12 15:09:14 -0700100 *
101 * Common implementation of firmware_map_add() and firmware_map_add_early()
102 * which expects a pre-allocated struct firmware_map_entry.
103 **/
Bernhard Walle69ac9cd2008-06-27 13:12:54 +0200104static int firmware_map_add_entry(resource_size_t start, resource_size_t end,
105 const char *type,
106 struct firmware_map_entry *entry)
107{
108 BUG_ON(start > end);
109
110 entry->start = start;
111 entry->end = end;
112 entry->type = type;
113 INIT_LIST_HEAD(&entry->list);
114 kobject_init(&entry->kobj, &memmap_ktype);
115
116 list_add_tail(&entry->list, &map_entries);
117
118 return 0;
119}
120
Bernhard Walle31bad922008-08-12 15:09:14 -0700121/**
122 * firmware_map_add() - Adds a firmware mapping entry.
123 * @start: Start of the memory range.
124 * @end: End of the memory range (inclusive).
125 * @type: Type of the memory range.
126 *
127 * This function uses kmalloc() for memory
128 * allocation. Use firmware_map_add_early() if you want to use the bootmem
129 * allocator.
130 *
131 * That function must be called before late_initcall.
132 *
133 * Returns 0 on success, or -ENOMEM if no memory could be allocated.
134 **/
Bernhard Walle69ac9cd2008-06-27 13:12:54 +0200135int firmware_map_add(resource_size_t start, resource_size_t end,
136 const char *type)
137{
138 struct firmware_map_entry *entry;
139
140 entry = kmalloc(sizeof(struct firmware_map_entry), GFP_ATOMIC);
Bernhard Walle69ac9cd2008-06-27 13:12:54 +0200141 if (!entry)
142 return -ENOMEM;
143
144 return firmware_map_add_entry(start, end, type, entry);
145}
146
Bernhard Walle31bad922008-08-12 15:09:14 -0700147/**
148 * firmware_map_add_early() - Adds a firmware mapping entry.
149 * @start: Start of the memory range.
150 * @end: End of the memory range (inclusive).
151 * @type: Type of the memory range.
152 *
153 * Adds a firmware mapping entry. This function uses the bootmem allocator
154 * for memory allocation. Use firmware_map_add() if you want to use kmalloc().
155 *
156 * That function must be called before late_initcall.
157 *
158 * Returns 0 on success, or -ENOMEM if no memory could be allocated.
159 **/
Bernhard Walle69ac9cd2008-06-27 13:12:54 +0200160int __init firmware_map_add_early(resource_size_t start, resource_size_t end,
161 const char *type)
162{
163 struct firmware_map_entry *entry;
164
165 entry = alloc_bootmem_low(sizeof(struct firmware_map_entry));
Bernhard Walle31bad922008-08-12 15:09:14 -0700166 if (WARN_ON(!entry))
Bernhard Walle69ac9cd2008-06-27 13:12:54 +0200167 return -ENOMEM;
168
169 return firmware_map_add_entry(start, end, type, entry);
170}
171
172/*
173 * Sysfs functions -------------------------------------------------------------
174 */
175
176static ssize_t start_show(struct firmware_map_entry *entry, char *buf)
177{
Randy Dunlap78681ac2008-07-26 15:22:28 -0700178 return snprintf(buf, PAGE_SIZE, "0x%llx\n",
179 (unsigned long long)entry->start);
Bernhard Walle69ac9cd2008-06-27 13:12:54 +0200180}
181
182static ssize_t end_show(struct firmware_map_entry *entry, char *buf)
183{
Randy Dunlap78681ac2008-07-26 15:22:28 -0700184 return snprintf(buf, PAGE_SIZE, "0x%llx\n",
185 (unsigned long long)entry->end);
Bernhard Walle69ac9cd2008-06-27 13:12:54 +0200186}
187
188static ssize_t type_show(struct firmware_map_entry *entry, char *buf)
189{
190 return snprintf(buf, PAGE_SIZE, "%s\n", entry->type);
191}
192
193#define to_memmap_attr(_attr) container_of(_attr, struct memmap_attribute, attr)
194#define to_memmap_entry(obj) container_of(obj, struct firmware_map_entry, kobj)
195
196static ssize_t memmap_attr_show(struct kobject *kobj,
197 struct attribute *attr, char *buf)
198{
199 struct firmware_map_entry *entry = to_memmap_entry(kobj);
200 struct memmap_attribute *memmap_attr = to_memmap_attr(attr);
201
202 return memmap_attr->show(entry, buf);
203}
204
205/*
206 * Initialises stuff and adds the entries in the map_entries list to
207 * sysfs. Important is that firmware_map_add() and firmware_map_add_early()
Bernhard Walle31bad922008-08-12 15:09:14 -0700208 * must be called before late_initcall. That's just because that function
209 * is called as late_initcall() function, which means that if you call
210 * firmware_map_add() or firmware_map_add_early() afterwards, the entries
211 * are not added to sysfs.
Bernhard Walle69ac9cd2008-06-27 13:12:54 +0200212 */
213static int __init memmap_init(void)
214{
215 int i = 0;
216 struct firmware_map_entry *entry;
217 struct kset *memmap_kset;
218
219 memmap_kset = kset_create_and_add("memmap", NULL, firmware_kobj);
Bernhard Walle31bad922008-08-12 15:09:14 -0700220 if (WARN_ON(!memmap_kset))
Bernhard Walle69ac9cd2008-06-27 13:12:54 +0200221 return -ENOMEM;
222
223 list_for_each_entry(entry, &map_entries, list) {
224 entry->kobj.kset = memmap_kset;
Bernhard Walle31bad922008-08-12 15:09:14 -0700225 if (kobject_add(&entry->kobj, NULL, "%d", i++))
226 kobject_put(&entry->kobj);
Bernhard Walle69ac9cd2008-06-27 13:12:54 +0200227 }
228
229 return 0;
230}
231late_initcall(memmap_init);
232