summaryrefslogtreecommitdiffstats
path: root/drivers/mtd/parsers/ofpart_core.c
blob: 192190c42fc84d3f8c8ba72465fa3c44bf5243e7 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
// SPDX-License-Identifier: GPL-2.0-or-later
/*
 * Flash partitions described by the OF (or flattened) device tree
 *
 * Copyright © 2006 MontaVista Software Inc.
 * Author: Vitaly Wool <vwool@ru.mvista.com>
 *
 * Revised to handle newer style flash binding by:
 *   Copyright © 2007 David Gibson, IBM Corporation.
 */

#include <linux/module.h>
#include <linux/init.h>
#include <linux/of.h>
#include <linux/mtd/mtd.h>
#include <linux/slab.h>
#include <linux/mtd/partitions.h>

#include "ofpart_bcm4908.h"
#include "ofpart_linksys_ns.h"

struct fixed_partitions_quirks {
	int (*post_parse)(struct mtd_info *mtd, struct mtd_partition *parts, int nr_parts);
};

static struct fixed_partitions_quirks bcm4908_partitions_quirks = {
	.post_parse = bcm4908_partitions_post_parse,
};

static struct fixed_partitions_quirks linksys_ns_partitions_quirks = {
	.post_parse = linksys_ns_partitions_post_parse,
};

static const struct of_device_id parse_ofpart_match_table[];

static bool node_has_compatible(struct device_node *pp)
{
	return of_get_property(pp, "compatible", NULL);
}

static int parse_fixed_partitions(struct mtd_info *master,
				  const struct mtd_partition **pparts,
				  struct mtd_part_parser_data *data)
{
	const struct fixed_partitions_quirks *quirks;
	const struct of_device_id *of_id;
	struct mtd_partition *parts;
	struct device_node *mtd_node;
	struct device_node *ofpart_node;
	const char *partname;
	struct device_node *pp;
	int nr_parts, i, ret = 0;
	bool dedicated = true;

	/* Pull of_node from the master device node */
	mtd_node = mtd_get_of_node(master);
	if (!mtd_node)
		return 0;

	if (!master->parent) { /* Master */
		ofpart_node = of_get_child_by_name(mtd_node, "partitions");
		if (!ofpart_node) {
			/*
			 * We might get here even when ofpart isn't used at all (e.g.,
			 * when using another parser), so don't be louder than
			 * KERN_DEBUG
			 */
			pr_debug("%s: 'partitions' subnode not found on %pOF. Trying to parse direct subnodes as partitions.\n",
				master->name, mtd_node);
			ofpart_node = mtd_node;
			dedicated = false;
		}
	} else { /* Partition */
		ofpart_node = mtd_node;
	}

	of_id = of_match_node(parse_ofpart_match_table, ofpart_node);
	if (dedicated && !of_id) {
		/* The 'partitions' subnode might be used by another parser */
		return 0;
	}

	quirks = of_id ? of_id->data : NULL;

	/* First count the subnodes */
	nr_parts = 0;
	for_each_child_of_node(ofpart_node,  pp) {
		if (!dedicated && node_has_compatible(pp))
			continue;

		nr_parts++;
	}

	if (nr_parts == 0)
		return 0;

	parts = kcalloc(nr_parts, sizeof(*parts), GFP_KERNEL);
	if (!parts)
		return -ENOMEM;

	i = 0;
	for_each_child_of_node(ofpart_node,  pp) {
		const __be32 *reg;
		int len;
		int a_cells, s_cells;

		if (!dedicated && node_has_compatible(pp))
			continue;

		reg = of_get_property(pp, "reg", &len);
		if (!reg) {
			if (dedicated) {
				pr_debug("%s: ofpart partition %pOF (%pOF) missing reg property.\n",
					 master->name, pp,
					 mtd_node);
				goto ofpart_fail;
			} else {
				nr_parts--;
				continue;
			}
		}

		a_cells = of_n_addr_cells(pp);
		s_cells = of_n_size_cells(pp);
		if (len / 4 != a_cells + s_cells) {
			pr_debug("%s: ofpart partition %pOF (%pOF) error parsing reg property.\n",
				 master->name, pp,
				 mtd_node);
			goto ofpart_fail;
		}

		parts[i].offset = of_read_number(reg, a_cells);
		parts[i].size = of_read_number(reg + a_cells, s_cells);
		parts[i].of_node = pp;

		partname = of_get_property(pp, "label", &len);
		if (!partname)
			partname = of_get_property(pp, "name", &len);
		parts[i].name = partname;

		if (of_get_property(pp, "read-only", &len))
			parts[i].mask_flags |= MTD_WRITEABLE;

		if (of_get_property(pp, "lock", &len))
			parts[i].mask_flags |= MTD_POWERUP_LOCK;

		if (of_property_read_bool(pp, "slc-mode"))
			parts[i].add_flags |= MTD_SLC_ON_MLC_EMULATION;

		i++;
	}

	if (!nr_parts)
		goto ofpart_none;

	if (quirks && quirks->post_parse)
		quirks->post_parse(master, parts, nr_parts);

	*pparts = parts;
	return nr_parts;

ofpart_fail:
	pr_err("%s: error parsing ofpart partition %pOF (%pOF)\n",
	       master->name, pp, mtd_node);
	ret = -EINVAL;
ofpart_none:
	of_node_put(pp);
	kfree(parts);
	return ret;
}

static const struct of_device_id parse_ofpart_match_table[] = {
	/* Generic */
	{ .compatible = "fixed-partitions" },
	/* Customized */
	{ .compatible = "brcm,bcm4908-partitions", .data = &bcm4908_partitions_quirks, },
	{ .compatible = "linksys,ns-partitions", .data = &linksys_ns_partitions_quirks, },
	{},
};
MODULE_DEVICE_TABLE(of, parse_ofpart_match_table);

static struct mtd_part_parser ofpart_parser = {
	.parse_fn = parse_fixed_partitions,
	.name = "fixed-partitions",
	.of_match_table = parse_ofpart_match_table,
};

static int parse_ofoldpart_partitions(struct mtd_info *master,
				      const struct mtd_partition **pparts,
				      struct mtd_part_parser_data *data)
{
	struct mtd_partition *parts;
	struct device_node *dp;
	int i, plen, nr_parts;
	const struct {
		__be32 offset, len;
	} *part;
	const char *names;

	/* Pull of_node from the master device node */
	dp = mtd_get_of_node(master);
	if (!dp)
		return 0;

	part = of_get_property(dp, "partitions", &plen);
	if (!part)
		return 0; /* No partitions found */

	pr_warn("Device tree uses obsolete partition map binding: %pOF\n", dp);

	nr_parts = plen / sizeof(part[0]);

	parts = kcalloc(nr_parts, sizeof(*parts), GFP_KERNEL);
	if (!parts)
		return -ENOMEM;

	names = of_get_property(dp, "partition-names", &plen);

	for (i = 0; i < nr_parts; i++) {
		parts[i].offset = be32_to_cpu(part->offset);
		parts[i].size   = be32_to_cpu(part->len) & ~1;
		/* bit 0 set signifies read only partition */
		if (be32_to_cpu(part->len) & 1)
			parts[i].mask_flags = MTD_WRITEABLE;

		if (names && (plen > 0)) {
			int len = strlen(names) + 1;

			parts[i].name = names;
			plen -= len;
			names += len;
		} else {
			parts[i].name = "unnamed";
		}

		part++;
	}

	*pparts = parts;
	return nr_parts;
}

static struct mtd_part_parser ofoldpart_parser = {
	.parse_fn = parse_ofoldpart_partitions,
	.name = "ofoldpart",
};

static int __init ofpart_parser_init(void)
{
	register_mtd_parser(&ofpart_parser);
	register_mtd_parser(&ofoldpart_parser);
	return 0;
}

static void __exit ofpart_parser_exit(void)
{
	deregister_mtd_parser(&ofpart_parser);
	deregister_mtd_parser(&ofoldpart_parser);
}

module_init(ofpart_parser_init);
module_exit(ofpart_parser_exit);

MODULE_LICENSE("GPL");
MODULE_DESCRIPTION("Parser for MTD partitioning information in device tree");
MODULE_AUTHOR("Vitaly Wool, David Gibson");
/*
 * When MTD core cannot find the requested parser, it tries to load the module
 * with the same name. Since we provide the ofoldpart parser, we should have
 * the corresponding alias.
 */
MODULE_ALIAS("fixed-partitions");
MODULE_ALIAS("ofoldpart");