1 /*
2 * Copyright © 2007 Eugene Konev <ejka@openwrt.org>
3 *
4 * This program is free software; you can redistribute it and/or modify
5 * it under the terms of the GNU General Public License as published by
6 * the Free Software Foundation; either version 2 of the License, or
7 * (at your option) any later version.
8 *
9 * This program is distributed in the hope that it will be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 * GNU General Public License for more details.
13 *
14 * You should have received a copy of the GNU General Public License
15 * along with this program; if not, write to the Free Software
16 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
17 *
18 * TI AR7 flash partition table.
19 * Based on ar7 map by Felix Fietkau <nbd@openwrt.org>
20 *
21 */
22
23 #include <linux/kernel.h>
24 #include <linux/slab.h>
25
26 #include <linux/mtd/mtd.h>
27 #include <linux/mtd/partitions.h>
28 #include <linux/bootmem.h>
29 #include <linux/module.h>
30
31 #include <uapi/linux/magic.h>
32
33 #define AR7_PARTS 4
34 #define ROOT_OFFSET 0xe0000
35
36 #define LOADER_MAGIC1 le32_to_cpu(0xfeedfa42)
37 #define LOADER_MAGIC2 le32_to_cpu(0xfeed1281)
38
39 struct ar7_bin_rec {
40 unsigned int checksum;
41 unsigned int length;
42 unsigned int address;
43 };
44
create_mtd_partitions(struct mtd_info * master,struct mtd_partition ** pparts,struct mtd_part_parser_data * data)45 static int create_mtd_partitions(struct mtd_info *master,
46 struct mtd_partition **pparts,
47 struct mtd_part_parser_data *data)
48 {
49 struct ar7_bin_rec header;
50 unsigned int offset;
51 size_t len;
52 unsigned int pre_size = master->erasesize, post_size = 0;
53 unsigned int root_offset = ROOT_OFFSET;
54
55 int retries = 10;
56 struct mtd_partition *ar7_parts;
57
58 ar7_parts = kzalloc(sizeof(*ar7_parts) * AR7_PARTS, GFP_KERNEL);
59 if (!ar7_parts)
60 return -ENOMEM;
61 ar7_parts[0].name = "loader";
62 ar7_parts[0].offset = 0;
63 ar7_parts[0].size = master->erasesize;
64 ar7_parts[0].mask_flags = MTD_WRITEABLE;
65
66 ar7_parts[1].name = "config";
67 ar7_parts[1].offset = 0;
68 ar7_parts[1].size = master->erasesize;
69 ar7_parts[1].mask_flags = 0;
70
71 do { /* Try 10 blocks starting from master->erasesize */
72 offset = pre_size;
73 mtd_read(master, offset, sizeof(header), &len,
74 (uint8_t *)&header);
75 if (!strncmp((char *)&header, "TIENV0.8", 8))
76 ar7_parts[1].offset = pre_size;
77 if (header.checksum == LOADER_MAGIC1)
78 break;
79 if (header.checksum == LOADER_MAGIC2)
80 break;
81 pre_size += master->erasesize;
82 } while (retries--);
83
84 pre_size = offset;
85
86 if (!ar7_parts[1].offset) {
87 ar7_parts[1].offset = master->size - master->erasesize;
88 post_size = master->erasesize;
89 }
90
91 switch (header.checksum) {
92 case LOADER_MAGIC1:
93 while (header.length) {
94 offset += sizeof(header) + header.length;
95 mtd_read(master, offset, sizeof(header), &len,
96 (uint8_t *)&header);
97 }
98 root_offset = offset + sizeof(header) + 4;
99 break;
100 case LOADER_MAGIC2:
101 while (header.length) {
102 offset += sizeof(header) + header.length;
103 mtd_read(master, offset, sizeof(header), &len,
104 (uint8_t *)&header);
105 }
106 root_offset = offset + sizeof(header) + 4 + 0xff;
107 root_offset &= ~(uint32_t)0xff;
108 break;
109 default:
110 printk(KERN_WARNING "Unknown magic: %08x\n", header.checksum);
111 break;
112 }
113
114 mtd_read(master, root_offset, sizeof(header), &len, (u8 *)&header);
115 if (header.checksum != SQUASHFS_MAGIC) {
116 root_offset += master->erasesize - 1;
117 root_offset &= ~(master->erasesize - 1);
118 }
119
120 ar7_parts[2].name = "linux";
121 ar7_parts[2].offset = pre_size;
122 ar7_parts[2].size = master->size - pre_size - post_size;
123 ar7_parts[2].mask_flags = 0;
124
125 ar7_parts[3].name = "rootfs";
126 ar7_parts[3].offset = root_offset;
127 ar7_parts[3].size = master->size - root_offset - post_size;
128 ar7_parts[3].mask_flags = 0;
129
130 *pparts = ar7_parts;
131 return AR7_PARTS;
132 }
133
134 static struct mtd_part_parser ar7_parser = {
135 .owner = THIS_MODULE,
136 .parse_fn = create_mtd_partitions,
137 .name = "ar7part",
138 };
139
ar7_parser_init(void)140 static int __init ar7_parser_init(void)
141 {
142 register_mtd_parser(&ar7_parser);
143 return 0;
144 }
145
ar7_parser_exit(void)146 static void __exit ar7_parser_exit(void)
147 {
148 deregister_mtd_parser(&ar7_parser);
149 }
150
151 module_init(ar7_parser_init);
152 module_exit(ar7_parser_exit);
153
154 MODULE_LICENSE("GPL");
155 MODULE_AUTHOR( "Felix Fietkau <nbd@openwrt.org>, "
156 "Eugene Konev <ejka@openwrt.org>");
157 MODULE_DESCRIPTION("MTD partitioning for TI AR7");
158