2 * Flash partitions described by the OF (or flattened) device tree
4 * Copyright © 2006 MontaVista Software Inc.
5 * Author: Vitaly Wool <vwool@ru.mvista.com>
7 * Revised to handle newer style flash binding by:
8 * Copyright © 2007 David Gibson, IBM Corporation.
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.
16 #include <linux/module.h>
17 #include <linux/init.h>
19 #include <linux/mtd/mtd.h>
20 #include <linux/slab.h>
21 #include <linux/mtd/partitions.h>
23 static bool node_has_compatible(struct device_node *pp)
25 return of_get_property(pp, "compatible", NULL);
28 static int parse_ofpart_partitions(struct mtd_info *master,
29 struct mtd_partition **pparts,
30 struct mtd_part_parser_data *data)
32 struct device_node *mtd_node;
33 struct device_node *ofpart_node;
35 struct device_node *pp;
36 int nr_parts, i, ret = 0;
37 bool dedicated = true;
43 mtd_node = data->of_node;
47 ofpart_node = of_get_child_by_name(mtd_node, "partitions");
50 * We might get here even when ofpart isn't used at all (e.g.,
51 * when using another parser), so don't be louder than
54 pr_debug("%s: 'partitions' subnode not found on %s. Trying to parse direct subnodes as partitions.\n",
55 master->name, mtd_node->full_name);
56 ofpart_node = mtd_node;
58 } else if (!of_device_is_compatible(ofpart_node, "fixed-partitions")) {
59 /* The 'partitions' subnode might be used by another parser */
63 /* First count the subnodes */
65 for_each_child_of_node(ofpart_node, pp) {
66 if (!dedicated && node_has_compatible(pp))
75 *pparts = kzalloc(nr_parts * sizeof(**pparts), GFP_KERNEL);
80 for_each_child_of_node(ofpart_node, pp) {
85 if (!dedicated && node_has_compatible(pp))
88 reg = of_get_property(pp, "reg", &len);
91 pr_debug("%s: ofpart partition %s (%s) missing reg property.\n",
92 master->name, pp->full_name,
101 a_cells = of_n_addr_cells(pp);
102 s_cells = of_n_size_cells(pp);
103 if (len / 4 != a_cells + s_cells) {
104 pr_debug("%s: ofpart partition %s (%s) error parsing reg property.\n",
105 master->name, pp->full_name,
106 mtd_node->full_name);
110 (*pparts)[i].offset = of_read_number(reg, a_cells);
111 (*pparts)[i].size = of_read_number(reg + a_cells, s_cells);
113 partname = of_get_property(pp, "label", &len);
115 partname = of_get_property(pp, "name", &len);
116 (*pparts)[i].name = partname;
118 if (of_get_property(pp, "read-only", &len))
119 (*pparts)[i].mask_flags |= MTD_WRITEABLE;
121 if (of_get_property(pp, "lock", &len))
122 (*pparts)[i].mask_flags |= MTD_POWERUP_LOCK;
133 pr_err("%s: error parsing ofpart partition %s (%s)\n",
134 master->name, pp->full_name, mtd_node->full_name);
143 static struct mtd_part_parser ofpart_parser = {
144 .owner = THIS_MODULE,
145 .parse_fn = parse_ofpart_partitions,
149 static int parse_ofoldpart_partitions(struct mtd_info *master,
150 struct mtd_partition **pparts,
151 struct mtd_part_parser_data *data)
153 struct device_node *dp;
154 int i, plen, nr_parts;
167 part = of_get_property(dp, "partitions", &plen);
169 return 0; /* No partitions found */
171 pr_warning("Device tree uses obsolete partition map binding: %s\n",
174 nr_parts = plen / sizeof(part[0]);
176 *pparts = kzalloc(nr_parts * sizeof(*(*pparts)), GFP_KERNEL);
180 names = of_get_property(dp, "partition-names", &plen);
182 for (i = 0; i < nr_parts; i++) {
183 (*pparts)[i].offset = be32_to_cpu(part->offset);
184 (*pparts)[i].size = be32_to_cpu(part->len) & ~1;
185 /* bit 0 set signifies read only partition */
186 if (be32_to_cpu(part->len) & 1)
187 (*pparts)[i].mask_flags = MTD_WRITEABLE;
189 if (names && (plen > 0)) {
190 int len = strlen(names) + 1;
192 (*pparts)[i].name = names;
196 (*pparts)[i].name = "unnamed";
205 static struct mtd_part_parser ofoldpart_parser = {
206 .owner = THIS_MODULE,
207 .parse_fn = parse_ofoldpart_partitions,
211 static int __init ofpart_parser_init(void)
213 register_mtd_parser(&ofpart_parser);
214 register_mtd_parser(&ofoldpart_parser);
218 static void __exit ofpart_parser_exit(void)
220 deregister_mtd_parser(&ofpart_parser);
221 deregister_mtd_parser(&ofoldpart_parser);
224 module_init(ofpart_parser_init);
225 module_exit(ofpart_parser_exit);
227 MODULE_LICENSE("GPL");
228 MODULE_DESCRIPTION("Parser for MTD partitioning information in device tree");
229 MODULE_AUTHOR("Vitaly Wool, David Gibson");
231 * When MTD core cannot find the requested parser, it tries to load the module
232 * with the same name. Since we provide the ofoldpart parser, we should have
233 * the corresponding alias.
235 MODULE_ALIAS("ofoldpart");