summaryrefslogtreecommitdiff
path: root/target/linux/ar7/files/drivers/mtd/ar7part.c
blob: 3d160d4cddefb05302fa21aa70b01bca4df34669 (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
/*
 * Copyright (C) 2007 Eugene Konev <ejka@openwrt.org>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
 *
 * TI AR7 flash partition table.
 * Based on ar7 map by Felix Fietkau <nbd@openwrt.org>
 *
 */

#include <linux/kernel.h>
#include <linux/slab.h>

#include <linux/mtd/mtd.h>
#include <linux/mtd/partitions.h>
#include <linux/bootmem.h>
#include <linux/magic.h>

#define AR7_PARTS	4
#define ROOT_OFFSET	0xe0000

#define LOADER_MAGIC1	le32_to_cpu(0xfeedfa42)
#define LOADER_MAGIC2	le32_to_cpu(0xfeed1281)

struct ar7_bin_rec {
	unsigned int checksum;
	unsigned int length;
	unsigned int address;
};

static struct mtd_partition ar7_parts[AR7_PARTS];

static int create_mtd_partitions(struct mtd_info *master,
				 struct mtd_partition **pparts,
				 unsigned long origin)
{
	struct ar7_bin_rec header;
	unsigned int offset, len;
	unsigned int pre_size = master->erasesize, post_size = 0;
	unsigned int root_offset = ROOT_OFFSET;

	int retries = 10;

	ar7_parts[0].name = "loader";
	ar7_parts[0].offset = 0;
	ar7_parts[0].size = master->erasesize;
	ar7_parts[0].mask_flags = MTD_WRITEABLE;

	ar7_parts[1].name = "config";
	ar7_parts[1].offset = 0;
	ar7_parts[1].size = master->erasesize;
	ar7_parts[1].mask_flags = 0;

	do { /* Try 10 blocks starting from master->erasesize */
		offset = pre_size;
		master->read(master, offset,
			sizeof(header), &len, (u8 *)&header);
		if (!strncmp((char *)&header, "TIENV0.8", 8))
			ar7_parts[1].offset = pre_size;
		if (header.checksum == LOADER_MAGIC1)
			break;
		if (header.checksum == LOADER_MAGIC2)
			break;
		pre_size += master->erasesize;
	} while (retries--);

	pre_size = offset;

	if (!ar7_parts[1].offset) {
		ar7_parts[1].offset = master->size - master->erasesize;
		post_size = master->erasesize;
	}

	switch (header.checksum) {
	case LOADER_MAGIC1:
		while (header.length) {
			offset += sizeof(header) + header.length;
			master->read(master, offset, sizeof(header),
				     &len, (u8 *)&header);
		}
		root_offset = offset + sizeof(header) + 4;
		break;
	case LOADER_MAGIC2:
		while (header.length) {
			offset += sizeof(header) + header.length;
			master->read(master, offset, sizeof(header),
				     &len, (u8 *)&header);
		}
		root_offset = offset + sizeof(header) + 4 + 0xff;
		root_offset &= ~(u32)0xff;
		break;
	default:
		printk(KERN_WARNING "Unknown magic: %08x\n", header.checksum);
		break;
	}

	master->read(master, root_offset,
		sizeof(header), &len, (u8 *)&header);
	if (header.checksum != SQUASHFS_MAGIC) {
		root_offset += master->erasesize - 1;
		root_offset &= ~(master->erasesize - 1);
	}

	ar7_parts[2].name = "linux";
	ar7_parts[2].offset = pre_size;
	ar7_parts[2].size = master->size - pre_size - post_size;
	ar7_parts[2].mask_flags = 0;

	ar7_parts[3].name = "rootfs";
	ar7_parts[3].offset = root_offset;
	ar7_parts[3].size = master->size - root_offset - post_size;
	ar7_parts[3].mask_flags = 0;

	*pparts = ar7_parts;
	return AR7_PARTS;
}

static struct mtd_part_parser ar7_parser = {
	.owner = THIS_MODULE,
	.parse_fn = create_mtd_partitions,
	.name = "ar7part",
};

static int __init ar7_parser_init(void)
{
	return register_mtd_parser(&ar7_parser);
}

module_init(ar7_parser_init);

MODULE_LICENSE("GPL");
MODULE_AUTHOR(	"Felix Fietkau <nbd@openwrt.org>, "
		"Eugene Konev <ejka@openwrt.org>");
MODULE_DESCRIPTION("MTD partitioning for TI AR7");