summaryrefslogtreecommitdiffstats
path: root/drivers/mtd/parsers/bcm63xxpart.c
blob: 78f90c6c18fd3a1e1248008d1795b0365b1b1c92 (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
// SPDX-License-Identifier: GPL-2.0-or-later
/*
 * BCM63XX CFE image tag parser
 *
 * Copyright © 2006-2008  Florian Fainelli <florian@openwrt.org>
 *			  Mike Albon <malbon@openwrt.org>
 * Copyright © 2009-2010  Daniel Dickinson <openwrt@cshore.neomailbox.net>
 * Copyright © 2011-2013  Jonas Gorski <jonas.gorski@gmail.com>
 */

#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt

#include <linux/bcm963xx_nvram.h>
#include <linux/bcm963xx_tag.h>
#include <linux/crc32.h>
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/sizes.h>
#include <linux/slab.h>
#include <linux/vmalloc.h>
#include <linux/mtd/mtd.h>
#include <linux/mtd/partitions.h>
#include <linux/of.h>

#define BCM963XX_CFE_BLOCK_SIZE		SZ_64K	/* always at least 64KiB */

#define BCM963XX_CFE_MAGIC_OFFSET	0x4e0
#define BCM963XX_CFE_VERSION_OFFSET	0x570
#define BCM963XX_NVRAM_OFFSET		0x580

/* Ensure strings read from flash structs are null terminated */
#define STR_NULL_TERMINATE(x) \
	do { char *_str = (x); _str[sizeof(x) - 1] = 0; } while (0)

static int bcm63xx_detect_cfe(struct mtd_info *master)
{
	char buf[9];
	int ret;
	size_t retlen;

	ret = mtd_read(master, BCM963XX_CFE_VERSION_OFFSET, 5, &retlen,
		       (void *)buf);
	buf[retlen] = 0;

	if (ret)
		return ret;

	if (strncmp("cfe-v", buf, 5) == 0)
		return 0;

	/* very old CFE's do not have the cfe-v string, so check for magic */
	ret = mtd_read(master, BCM963XX_CFE_MAGIC_OFFSET, 8, &retlen,
		       (void *)buf);
	buf[retlen] = 0;

	return strncmp("CFE1CFE1", buf, 8);
}

static int bcm63xx_read_nvram(struct mtd_info *master,
	struct bcm963xx_nvram *nvram)
{
	u32 actual_crc, expected_crc;
	size_t retlen;
	int ret;

	/* extract nvram data */
	ret = mtd_read(master, BCM963XX_NVRAM_OFFSET, BCM963XX_NVRAM_V5_SIZE,
			&retlen, (void *)nvram);
	if (ret)
		return ret;

	ret = bcm963xx_nvram_checksum(nvram, &expected_crc, &actual_crc);
	if (ret)
		pr_warn("nvram checksum failed, contents may be invalid (expected %08x, got %08x)\n",
			expected_crc, actual_crc);

	if (!nvram->psi_size)
		nvram->psi_size = BCM963XX_DEFAULT_PSI_SIZE;

	return 0;
}

static const char * const bcm63xx_cfe_part_types[] = {
	"bcm963xx-imagetag",
	NULL,
};

static int bcm63xx_parse_cfe_nor_partitions(struct mtd_info *master,
	const struct mtd_partition **pparts, struct bcm963xx_nvram *nvram)
{
	struct mtd_partition *parts;
	int nrparts = 3, curpart = 0;
	unsigned int cfelen, nvramlen;
	unsigned int cfe_erasesize;
	int i;

	cfe_erasesize = max_t(uint32_t, master->erasesize,
			      BCM963XX_CFE_BLOCK_SIZE);

	cfelen = cfe_erasesize;
	nvramlen = nvram->psi_size * SZ_1K;
	nvramlen = roundup(nvramlen, cfe_erasesize);

	parts = kzalloc(sizeof(*parts) * nrparts + 10 * nrparts, GFP_KERNEL);
	if (!parts)
		return -ENOMEM;

	/* Start building partition list */
	parts[curpart].name = "CFE";
	parts[curpart].offset = 0;
	parts[curpart].size = cfelen;
	curpart++;

	parts[curpart].name = "nvram";
	parts[curpart].offset = master->size - nvramlen;
	parts[curpart].size = nvramlen;
	curpart++;

	/* Global partition "linux" to make easy firmware upgrade */
	parts[curpart].name = "linux";
	parts[curpart].offset = cfelen;
	parts[curpart].size = master->size - cfelen - nvramlen;
	parts[curpart].types = bcm63xx_cfe_part_types;

	for (i = 0; i < nrparts; i++)
		pr_info("Partition %d is %s offset %llx and length %llx\n", i,
			parts[i].name, parts[i].offset,	parts[i].size);

	*pparts = parts;

	return nrparts;
}

static int bcm63xx_parse_cfe_partitions(struct mtd_info *master,
					const struct mtd_partition **pparts,
					struct mtd_part_parser_data *data)
{
	struct bcm963xx_nvram *nvram = NULL;
	int ret;

	if (bcm63xx_detect_cfe(master))
		return -EINVAL;

	nvram = vzalloc(sizeof(*nvram));
	if (!nvram)
		return -ENOMEM;

	ret = bcm63xx_read_nvram(master, nvram);
	if (ret)
		goto out;

	if (!mtd_type_is_nand(master))
		ret = bcm63xx_parse_cfe_nor_partitions(master, pparts, nvram);
	else
		ret = -EINVAL;

out:
	vfree(nvram);
	return ret;
};

static const struct of_device_id parse_bcm63xx_cfe_match_table[] = {
	{ .compatible = "brcm,bcm963xx-cfe-nor-partitions" },
	{},
};
MODULE_DEVICE_TABLE(of, parse_bcm63xx_cfe_match_table);

static struct mtd_part_parser bcm63xx_cfe_parser = {
	.parse_fn = bcm63xx_parse_cfe_partitions,
	.name = "bcm63xxpart",
	.of_match_table = parse_bcm63xx_cfe_match_table,
};
module_mtd_part_parser(bcm63xx_cfe_parser);

MODULE_LICENSE("GPL");
MODULE_AUTHOR("Daniel Dickinson <openwrt@cshore.neomailbox.net>");
MODULE_AUTHOR("Florian Fainelli <florian@openwrt.org>");
MODULE_AUTHOR("Mike Albon <malbon@openwrt.org>");
MODULE_AUTHOR("Jonas Gorski <jonas.gorski@gmail.com");
MODULE_DESCRIPTION("MTD partitioning for BCM63XX CFE bootloaders");