1*4882a593Smuzhiyun // SPDX-License-Identifier: GPL-2.0-only
2*4882a593Smuzhiyun /*
3*4882a593Smuzhiyun * Parser for TRX format partitions
4*4882a593Smuzhiyun *
5*4882a593Smuzhiyun * Copyright (C) 2012 - 2017 Rafał Miłecki <rafal@milecki.pl>
6*4882a593Smuzhiyun */
7*4882a593Smuzhiyun
8*4882a593Smuzhiyun #include <linux/module.h>
9*4882a593Smuzhiyun #include <linux/slab.h>
10*4882a593Smuzhiyun #include <linux/mtd/mtd.h>
11*4882a593Smuzhiyun #include <linux/mtd/partitions.h>
12*4882a593Smuzhiyun
13*4882a593Smuzhiyun #define TRX_PARSER_MAX_PARTS 4
14*4882a593Smuzhiyun
15*4882a593Smuzhiyun /* Magics */
16*4882a593Smuzhiyun #define TRX_MAGIC 0x30524448
17*4882a593Smuzhiyun #define UBI_EC_MAGIC 0x23494255 /* UBI# */
18*4882a593Smuzhiyun
19*4882a593Smuzhiyun struct trx_header {
20*4882a593Smuzhiyun uint32_t magic;
21*4882a593Smuzhiyun uint32_t length;
22*4882a593Smuzhiyun uint32_t crc32;
23*4882a593Smuzhiyun uint16_t flags;
24*4882a593Smuzhiyun uint16_t version;
25*4882a593Smuzhiyun uint32_t offset[3];
26*4882a593Smuzhiyun } __packed;
27*4882a593Smuzhiyun
parser_trx_data_part_name(struct mtd_info * master,size_t offset)28*4882a593Smuzhiyun static const char *parser_trx_data_part_name(struct mtd_info *master,
29*4882a593Smuzhiyun size_t offset)
30*4882a593Smuzhiyun {
31*4882a593Smuzhiyun uint32_t buf;
32*4882a593Smuzhiyun size_t bytes_read;
33*4882a593Smuzhiyun int err;
34*4882a593Smuzhiyun
35*4882a593Smuzhiyun err = mtd_read(master, offset, sizeof(buf), &bytes_read,
36*4882a593Smuzhiyun (uint8_t *)&buf);
37*4882a593Smuzhiyun if (err && !mtd_is_bitflip(err)) {
38*4882a593Smuzhiyun pr_err("mtd_read error while parsing (offset: 0x%zX): %d\n",
39*4882a593Smuzhiyun offset, err);
40*4882a593Smuzhiyun goto out_default;
41*4882a593Smuzhiyun }
42*4882a593Smuzhiyun
43*4882a593Smuzhiyun if (buf == UBI_EC_MAGIC)
44*4882a593Smuzhiyun return "ubi";
45*4882a593Smuzhiyun
46*4882a593Smuzhiyun out_default:
47*4882a593Smuzhiyun return "rootfs";
48*4882a593Smuzhiyun }
49*4882a593Smuzhiyun
parser_trx_parse(struct mtd_info * mtd,const struct mtd_partition ** pparts,struct mtd_part_parser_data * data)50*4882a593Smuzhiyun static int parser_trx_parse(struct mtd_info *mtd,
51*4882a593Smuzhiyun const struct mtd_partition **pparts,
52*4882a593Smuzhiyun struct mtd_part_parser_data *data)
53*4882a593Smuzhiyun {
54*4882a593Smuzhiyun struct mtd_partition *parts;
55*4882a593Smuzhiyun struct mtd_partition *part;
56*4882a593Smuzhiyun struct trx_header trx;
57*4882a593Smuzhiyun size_t bytes_read;
58*4882a593Smuzhiyun uint8_t curr_part = 0, i = 0;
59*4882a593Smuzhiyun int err;
60*4882a593Smuzhiyun
61*4882a593Smuzhiyun parts = kcalloc(TRX_PARSER_MAX_PARTS, sizeof(struct mtd_partition),
62*4882a593Smuzhiyun GFP_KERNEL);
63*4882a593Smuzhiyun if (!parts)
64*4882a593Smuzhiyun return -ENOMEM;
65*4882a593Smuzhiyun
66*4882a593Smuzhiyun err = mtd_read(mtd, 0, sizeof(trx), &bytes_read, (uint8_t *)&trx);
67*4882a593Smuzhiyun if (err) {
68*4882a593Smuzhiyun pr_err("MTD reading error: %d\n", err);
69*4882a593Smuzhiyun kfree(parts);
70*4882a593Smuzhiyun return err;
71*4882a593Smuzhiyun }
72*4882a593Smuzhiyun
73*4882a593Smuzhiyun if (trx.magic != TRX_MAGIC) {
74*4882a593Smuzhiyun kfree(parts);
75*4882a593Smuzhiyun return -ENOENT;
76*4882a593Smuzhiyun }
77*4882a593Smuzhiyun
78*4882a593Smuzhiyun /* We have LZMA loader if there is address in offset[2] */
79*4882a593Smuzhiyun if (trx.offset[2]) {
80*4882a593Smuzhiyun part = &parts[curr_part++];
81*4882a593Smuzhiyun part->name = "loader";
82*4882a593Smuzhiyun part->offset = trx.offset[i];
83*4882a593Smuzhiyun i++;
84*4882a593Smuzhiyun }
85*4882a593Smuzhiyun
86*4882a593Smuzhiyun if (trx.offset[i]) {
87*4882a593Smuzhiyun part = &parts[curr_part++];
88*4882a593Smuzhiyun part->name = "linux";
89*4882a593Smuzhiyun part->offset = trx.offset[i];
90*4882a593Smuzhiyun i++;
91*4882a593Smuzhiyun }
92*4882a593Smuzhiyun
93*4882a593Smuzhiyun if (trx.offset[i]) {
94*4882a593Smuzhiyun part = &parts[curr_part++];
95*4882a593Smuzhiyun part->name = parser_trx_data_part_name(mtd, trx.offset[i]);
96*4882a593Smuzhiyun part->offset = trx.offset[i];
97*4882a593Smuzhiyun i++;
98*4882a593Smuzhiyun }
99*4882a593Smuzhiyun
100*4882a593Smuzhiyun /*
101*4882a593Smuzhiyun * Assume that every partition ends at the beginning of the one it is
102*4882a593Smuzhiyun * followed by.
103*4882a593Smuzhiyun */
104*4882a593Smuzhiyun for (i = 0; i < curr_part; i++) {
105*4882a593Smuzhiyun u64 next_part_offset = (i < curr_part - 1) ?
106*4882a593Smuzhiyun parts[i + 1].offset : mtd->size;
107*4882a593Smuzhiyun
108*4882a593Smuzhiyun parts[i].size = next_part_offset - parts[i].offset;
109*4882a593Smuzhiyun }
110*4882a593Smuzhiyun
111*4882a593Smuzhiyun *pparts = parts;
112*4882a593Smuzhiyun return i;
113*4882a593Smuzhiyun };
114*4882a593Smuzhiyun
115*4882a593Smuzhiyun static const struct of_device_id mtd_parser_trx_of_match_table[] = {
116*4882a593Smuzhiyun { .compatible = "brcm,trx" },
117*4882a593Smuzhiyun {},
118*4882a593Smuzhiyun };
119*4882a593Smuzhiyun MODULE_DEVICE_TABLE(of, mtd_parser_trx_of_match_table);
120*4882a593Smuzhiyun
121*4882a593Smuzhiyun static struct mtd_part_parser mtd_parser_trx = {
122*4882a593Smuzhiyun .parse_fn = parser_trx_parse,
123*4882a593Smuzhiyun .name = "trx",
124*4882a593Smuzhiyun .of_match_table = mtd_parser_trx_of_match_table,
125*4882a593Smuzhiyun };
126*4882a593Smuzhiyun module_mtd_part_parser(mtd_parser_trx);
127*4882a593Smuzhiyun
128*4882a593Smuzhiyun MODULE_LICENSE("GPL v2");
129*4882a593Smuzhiyun MODULE_DESCRIPTION("Parser for TRX format partitions");
130