tjh.dev
Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
1/*
2 * Flash partitions described by the OF (or flattened) device tree
3 *
4 * Copyright © 2006 MontaVista Software Inc.
5 * Author: Vitaly Wool <vwool@ru.mvista.com>
6 *
7 * Revised to handle newer style flash binding by:
8 * Copyright © 2007 David Gibson, IBM Corporation.
9 *
10 * This program is free software; you can redistribute it and/or modify it
11 * under the terms of the GNU General Public License as published by the
12 * Free Software Foundation; either version 2 of the License, or (at your
13 * option) any later version.
14 */
15
16#include <linux/module.h>
17#include <linux/init.h>
18#include <linux/of.h>
19#include <linux/mtd/mtd.h>
20#include <linux/slab.h>
21#include <linux/mtd/partitions.h>
22
23static int parse_ofpart_partitions(struct mtd_info *master,
24 struct mtd_partition **pparts,
25 struct mtd_part_parser_data *data)
26{
27 struct device_node *node;
28 const char *partname;
29 struct device_node *pp;
30 int nr_parts, i;
31
32
33 if (!data)
34 return 0;
35
36 node = data->of_node;
37 if (!node)
38 return 0;
39
40 /* First count the subnodes */
41 pp = NULL;
42 nr_parts = 0;
43 while ((pp = of_get_next_child(node, pp)))
44 nr_parts++;
45
46 if (nr_parts == 0)
47 return 0;
48
49 *pparts = kzalloc(nr_parts * sizeof(**pparts), GFP_KERNEL);
50 if (!*pparts)
51 return -ENOMEM;
52
53 pp = NULL;
54 i = 0;
55 while ((pp = of_get_next_child(node, pp))) {
56 const __be32 *reg;
57 int len;
58
59 reg = of_get_property(pp, "reg", &len);
60 if (!reg) {
61 nr_parts--;
62 continue;
63 }
64
65 (*pparts)[i].offset = be32_to_cpu(reg[0]);
66 (*pparts)[i].size = be32_to_cpu(reg[1]);
67
68 partname = of_get_property(pp, "label", &len);
69 if (!partname)
70 partname = of_get_property(pp, "name", &len);
71 (*pparts)[i].name = (char *)partname;
72
73 if (of_get_property(pp, "read-only", &len))
74 (*pparts)[i].mask_flags |= MTD_WRITEABLE;
75
76 if (of_get_property(pp, "lock", &len))
77 (*pparts)[i].mask_flags |= MTD_POWERUP_LOCK;
78
79 i++;
80 }
81
82 if (!i) {
83 of_node_put(pp);
84 pr_err("No valid partition found on %s\n", node->full_name);
85 kfree(*pparts);
86 *pparts = NULL;
87 return -EINVAL;
88 }
89
90 return nr_parts;
91}
92
93static struct mtd_part_parser ofpart_parser = {
94 .owner = THIS_MODULE,
95 .parse_fn = parse_ofpart_partitions,
96 .name = "ofpart",
97};
98
99static int parse_ofoldpart_partitions(struct mtd_info *master,
100 struct mtd_partition **pparts,
101 struct mtd_part_parser_data *data)
102{
103 struct device_node *dp;
104 int i, plen, nr_parts;
105 const struct {
106 __be32 offset, len;
107 } *part;
108 const char *names;
109
110 if (!data)
111 return 0;
112
113 dp = data->of_node;
114 if (!dp)
115 return 0;
116
117 part = of_get_property(dp, "partitions", &plen);
118 if (!part)
119 return 0; /* No partitions found */
120
121 pr_warning("Device tree uses obsolete partition map binding: %s\n",
122 dp->full_name);
123
124 nr_parts = plen / sizeof(part[0]);
125
126 *pparts = kzalloc(nr_parts * sizeof(*(*pparts)), GFP_KERNEL);
127 if (!*pparts)
128 return -ENOMEM;
129
130 names = of_get_property(dp, "partition-names", &plen);
131
132 for (i = 0; i < nr_parts; i++) {
133 (*pparts)[i].offset = be32_to_cpu(part->offset);
134 (*pparts)[i].size = be32_to_cpu(part->len) & ~1;
135 /* bit 0 set signifies read only partition */
136 if (be32_to_cpu(part->len) & 1)
137 (*pparts)[i].mask_flags = MTD_WRITEABLE;
138
139 if (names && (plen > 0)) {
140 int len = strlen(names) + 1;
141
142 (*pparts)[i].name = (char *)names;
143 plen -= len;
144 names += len;
145 } else {
146 (*pparts)[i].name = "unnamed";
147 }
148
149 part++;
150 }
151
152 return nr_parts;
153}
154
155static struct mtd_part_parser ofoldpart_parser = {
156 .owner = THIS_MODULE,
157 .parse_fn = parse_ofoldpart_partitions,
158 .name = "ofoldpart",
159};
160
161static int __init ofpart_parser_init(void)
162{
163 int rc;
164 rc = register_mtd_parser(&ofpart_parser);
165 if (rc)
166 goto out;
167
168 rc = register_mtd_parser(&ofoldpart_parser);
169 if (!rc)
170 return 0;
171
172 deregister_mtd_parser(&ofoldpart_parser);
173out:
174 return rc;
175}
176
177static void __exit ofpart_parser_exit(void)
178{
179 deregister_mtd_parser(&ofpart_parser);
180 deregister_mtd_parser(&ofoldpart_parser);
181}
182
183module_init(ofpart_parser_init);
184module_exit(ofpart_parser_exit);
185
186MODULE_LICENSE("GPL");
187MODULE_DESCRIPTION("Parser for MTD partitioning information in device tree");
188MODULE_AUTHOR("Vitaly Wool, David Gibson");
189/*
190 * When MTD core cannot find the requested parser, it tries to load the module
191 * with the same name. Since we provide the ofoldpart parser, we should have
192 * the corresponding alias.
193 */
194MODULE_ALIAS("ofoldpart");