Commit | Line | Data |
---|---|---|
3cf7f131 RM |
1 | /* |
2 | * BCM47XX MTD partitioning | |
3 | * | |
4 | * Copyright © 2012 Rafał Miłecki <zajec5@gmail.com> | |
5 | * | |
6 | * This program is free software; you can redistribute it and/or modify | |
7 | * it under the terms of the GNU General Public License version 2 as | |
8 | * published by the Free Software Foundation. | |
9 | * | |
10 | */ | |
11 | ||
89a0d9a9 | 12 | #include <linux/bcm47xx_nvram.h> |
3cf7f131 RM |
13 | #include <linux/module.h> |
14 | #include <linux/kernel.h> | |
15 | #include <linux/slab.h> | |
16 | #include <linux/mtd/mtd.h> | |
17 | #include <linux/mtd/partitions.h> | |
3cf7f131 | 18 | |
0b56d2d4 RM |
19 | #include <uapi/linux/magic.h> |
20 | ||
59af5c7a RM |
21 | /* |
22 | * NAND flash on Netgear R6250 was verified to contain 15 partitions. | |
23 | * This will result in allocating too big array for some old devices, but the | |
24 | * memory will be freed soon anyway (see mtd_device_parse_register). | |
25 | */ | |
26 | #define BCM47XXPART_MAX_PARTS 20 | |
3cf7f131 | 27 | |
5ca1088f RM |
28 | /* |
29 | * Amount of bytes we read when analyzing each block of flash memory. | |
30 | * Set it big enough to allow detecting partition and reading important data. | |
31 | */ | |
4f8aaf72 | 32 | #define BCM47XXPART_BYTES_TO_READ 0x4e8 |
5ca1088f | 33 | |
3cf7f131 RM |
34 | /* Magics */ |
35 | #define BOARD_DATA_MAGIC 0x5246504D /* MPFR */ | |
f0501e81 | 36 | #define BOARD_DATA_MAGIC2 0xBD0D0BBD |
4f8aaf72 | 37 | #define CFE_MAGIC 0x43464531 /* 1EFC */ |
33094c73 | 38 | #define FACTORY_MAGIC 0x59544346 /* FCTY */ |
9e3afa5f | 39 | #define NVRAM_HEADER 0x48534C46 /* FLSH */ |
3cf7f131 RM |
40 | #define POT_MAGIC1 0x54544f50 /* POTT */ |
41 | #define POT_MAGIC2 0x504f /* OP */ | |
42 | #define ML_MAGIC1 0x39685a42 | |
43 | #define ML_MAGIC2 0x26594131 | |
44 | #define TRX_MAGIC 0x30524448 | |
0b56d2d4 | 45 | #define SHSQ_MAGIC 0x71736873 /* shsq (weird ZTE H218N endianness) */ |
99352afe RM |
46 | |
47 | static const char * const trx_types[] = { "trx", NULL }; | |
3cf7f131 RM |
48 | |
49 | struct trx_header { | |
50 | uint32_t magic; | |
51 | uint32_t length; | |
52 | uint32_t crc32; | |
53 | uint16_t flags; | |
54 | uint16_t version; | |
55 | uint32_t offset[3]; | |
56 | } __packed; | |
57 | ||
bd10c26a | 58 | static void bcm47xxpart_add_part(struct mtd_partition *part, const char *name, |
3cf7f131 RM |
59 | u64 offset, uint32_t mask_flags) |
60 | { | |
61 | part->name = name; | |
62 | part->offset = offset; | |
63 | part->mask_flags = mask_flags; | |
64 | } | |
65 | ||
89a0d9a9 RM |
66 | /** |
67 | * bcm47xxpart_bootpartition - gets index of TRX partition used by bootloader | |
68 | * | |
69 | * Some devices may have more than one TRX partition. In such case one of them | |
70 | * is the main one and another a failsafe one. Bootloader may fallback to the | |
71 | * failsafe firmware if it detects corruption of the main image. | |
72 | * | |
73 | * This function provides info about currently used TRX partition. It's the one | |
74 | * containing kernel started by the bootloader. | |
75 | */ | |
76 | static int bcm47xxpart_bootpartition(void) | |
77 | { | |
78 | char buf[4]; | |
79 | int bootpartition; | |
80 | ||
81 | /* Check CFE environment variable */ | |
82 | if (bcm47xx_nvram_getenv("bootpartition", buf, sizeof(buf)) > 0) { | |
83 | if (!kstrtoint(buf, 0, &bootpartition)) | |
84 | return bootpartition; | |
85 | } | |
86 | ||
87 | return 0; | |
88 | } | |
89 | ||
3cf7f131 | 90 | static int bcm47xxpart_parse(struct mtd_info *master, |
b9adf469 | 91 | const struct mtd_partition **pparts, |
3cf7f131 RM |
92 | struct mtd_part_parser_data *data) |
93 | { | |
94 | struct mtd_partition *parts; | |
95 | uint8_t i, curr_part = 0; | |
96 | uint32_t *buf; | |
97 | size_t bytes_read; | |
98 | uint32_t offset; | |
25bad1d3 | 99 | uint32_t blocksize = master->erasesize; |
89a0d9a9 RM |
100 | int trx_parts[2]; /* Array with indexes of TRX partitions */ |
101 | int trx_num = 0; /* Number of found TRX partitions */ | |
91d542f4 | 102 | int possible_nvram_sizes[] = { 0x8000, 0xF000, 0x10000, }; |
36bcc0c9 | 103 | int err; |
3cf7f131 | 104 | |
16bd87b3 RM |
105 | /* |
106 | * Some really old flashes (like AT45DB*) had smaller erasesize-s, but | |
107 | * partitions were aligned to at least 0x1000 anyway. | |
108 | */ | |
109 | if (blocksize < 0x1000) | |
110 | blocksize = 0x1000; | |
3cf7f131 RM |
111 | |
112 | /* Alloc */ | |
113 | parts = kzalloc(sizeof(struct mtd_partition) * BCM47XXPART_MAX_PARTS, | |
114 | GFP_KERNEL); | |
99b1d188 HM |
115 | if (!parts) |
116 | return -ENOMEM; | |
117 | ||
5ca1088f | 118 | buf = kzalloc(BCM47XXPART_BYTES_TO_READ, GFP_KERNEL); |
99b1d188 HM |
119 | if (!buf) { |
120 | kfree(parts); | |
121 | return -ENOMEM; | |
122 | } | |
3cf7f131 RM |
123 | |
124 | /* Parse block by block looking for magics */ | |
125 | for (offset = 0; offset <= master->size - blocksize; | |
126 | offset += blocksize) { | |
2a36a5c3 | 127 | /* Nothing more in higher memory on BCM47XX (MIPS) */ |
97f2645f | 128 | if (IS_ENABLED(CONFIG_BCM47XX) && offset >= 0x2000000) |
3cf7f131 RM |
129 | break; |
130 | ||
00b79860 | 131 | if (curr_part >= BCM47XXPART_MAX_PARTS) { |
3cf7f131 RM |
132 | pr_warn("Reached maximum number of partitions, scanning stopped!\n"); |
133 | break; | |
134 | } | |
135 | ||
136 | /* Read beginning of the block */ | |
36bcc0c9 RM |
137 | err = mtd_read(master, offset, BCM47XXPART_BYTES_TO_READ, |
138 | &bytes_read, (uint8_t *)buf); | |
139 | if (err && !mtd_is_bitflip(err)) { | |
140 | pr_err("mtd_read error while parsing (offset: 0x%X): %d\n", | |
141 | offset, err); | |
3cf7f131 RM |
142 | continue; |
143 | } | |
144 | ||
4f8aaf72 RM |
145 | /* Magic or small NVRAM at 0x400 */ |
146 | if ((buf[0x4e0 / 4] == CFE_MAGIC && buf[0x4e4 / 4] == CFE_MAGIC) || | |
147 | (buf[0x400 / 4] == NVRAM_HEADER)) { | |
3cf7f131 RM |
148 | bcm47xxpart_add_part(&parts[curr_part++], "boot", |
149 | offset, MTD_WRITEABLE); | |
150 | continue; | |
151 | } | |
152 | ||
3cf7f131 RM |
153 | /* |
154 | * board_data starts with board_id which differs across boards, | |
155 | * but we can use 'MPFR' (hopefully) magic at 0x100 | |
156 | */ | |
157 | if (buf[0x100 / 4] == BOARD_DATA_MAGIC) { | |
158 | bcm47xxpart_add_part(&parts[curr_part++], "board_data", | |
159 | offset, MTD_WRITEABLE); | |
160 | continue; | |
161 | } | |
162 | ||
33094c73 RM |
163 | /* Found on Huawei E970 */ |
164 | if (buf[0x000 / 4] == FACTORY_MAGIC) { | |
165 | bcm47xxpart_add_part(&parts[curr_part++], "factory", | |
166 | offset, MTD_WRITEABLE); | |
167 | continue; | |
168 | } | |
169 | ||
3cf7f131 RM |
170 | /* POT(TOP) */ |
171 | if (buf[0x000 / 4] == POT_MAGIC1 && | |
172 | (buf[0x004 / 4] & 0xFFFF) == POT_MAGIC2) { | |
173 | bcm47xxpart_add_part(&parts[curr_part++], "POT", offset, | |
174 | MTD_WRITEABLE); | |
175 | continue; | |
176 | } | |
177 | ||
178 | /* ML */ | |
179 | if (buf[0x010 / 4] == ML_MAGIC1 && | |
180 | buf[0x014 / 4] == ML_MAGIC2) { | |
181 | bcm47xxpart_add_part(&parts[curr_part++], "ML", offset, | |
182 | MTD_WRITEABLE); | |
183 | continue; | |
184 | } | |
185 | ||
186 | /* TRX */ | |
187 | if (buf[0x000 / 4] == TRX_MAGIC) { | |
b522d7b0 | 188 | struct trx_header *trx; |
3cf7f131 | 189 | |
89a0d9a9 RM |
190 | if (trx_num >= ARRAY_SIZE(trx_parts)) |
191 | pr_warn("No enough space to store another TRX found at 0x%X\n", | |
192 | offset); | |
193 | else | |
194 | trx_parts[trx_num++] = curr_part; | |
396afe55 RM |
195 | bcm47xxpart_add_part(&parts[curr_part++], "firmware", |
196 | offset, 0); | |
197 | ||
bd5d2131 | 198 | /* Jump to the end of TRX */ |
b522d7b0 | 199 | trx = (struct trx_header *)buf; |
bd5d2131 RM |
200 | offset = roundup(offset + trx->length, blocksize); |
201 | /* Next loop iteration will increase the offset */ | |
202 | offset -= blocksize; | |
3cf7f131 RM |
203 | continue; |
204 | } | |
020c6bcf RM |
205 | |
206 | /* Squashfs on devices not using TRX */ | |
0b56d2d4 RM |
207 | if (le32_to_cpu(buf[0x000 / 4]) == SQUASHFS_MAGIC || |
208 | buf[0x000 / 4] == SHSQ_MAGIC) { | |
020c6bcf RM |
209 | bcm47xxpart_add_part(&parts[curr_part++], "rootfs", |
210 | offset, 0); | |
211 | continue; | |
024629fd RM |
212 | } |
213 | ||
214 | /* | |
215 | * New (ARM?) devices may have NVRAM in some middle block. Last | |
216 | * block will be checked later, so skip it. | |
217 | */ | |
218 | if (offset != master->size - blocksize && | |
219 | buf[0x000 / 4] == NVRAM_HEADER) { | |
220 | bcm47xxpart_add_part(&parts[curr_part++], "nvram", | |
221 | offset, 0); | |
222 | continue; | |
020c6bcf | 223 | } |
f0501e81 RM |
224 | |
225 | /* Read middle of the block */ | |
36bcc0c9 RM |
226 | err = mtd_read(master, offset + 0x8000, 0x4, &bytes_read, |
227 | (uint8_t *)buf); | |
228 | if (err && !mtd_is_bitflip(err)) { | |
229 | pr_err("mtd_read error while parsing (offset: 0x%X): %d\n", | |
230 | offset, err); | |
f0501e81 RM |
231 | continue; |
232 | } | |
233 | ||
234 | /* Some devices (ex. WNDR3700v3) don't have a standard 'MPFR' */ | |
235 | if (buf[0x000 / 4] == BOARD_DATA_MAGIC2) { | |
236 | bcm47xxpart_add_part(&parts[curr_part++], "board_data", | |
237 | offset, MTD_WRITEABLE); | |
238 | continue; | |
239 | } | |
3cf7f131 | 240 | } |
91d542f4 RM |
241 | |
242 | /* Look for NVRAM at the end of the last block. */ | |
243 | for (i = 0; i < ARRAY_SIZE(possible_nvram_sizes); i++) { | |
00b79860 | 244 | if (curr_part >= BCM47XXPART_MAX_PARTS) { |
91d542f4 RM |
245 | pr_warn("Reached maximum number of partitions, scanning stopped!\n"); |
246 | break; | |
247 | } | |
248 | ||
249 | offset = master->size - possible_nvram_sizes[i]; | |
36bcc0c9 RM |
250 | err = mtd_read(master, offset, 0x4, &bytes_read, |
251 | (uint8_t *)buf); | |
252 | if (err && !mtd_is_bitflip(err)) { | |
253 | pr_err("mtd_read error while reading (offset 0x%X): %d\n", | |
254 | offset, err); | |
91d542f4 RM |
255 | continue; |
256 | } | |
257 | ||
258 | /* Standard NVRAM */ | |
259 | if (buf[0] == NVRAM_HEADER) { | |
260 | bcm47xxpart_add_part(&parts[curr_part++], "nvram", | |
261 | master->size - blocksize, 0); | |
262 | break; | |
263 | } | |
264 | } | |
265 | ||
3cf7f131 RM |
266 | kfree(buf); |
267 | ||
268 | /* | |
269 | * Assume that partitions end at the beginning of the one they are | |
270 | * followed by. | |
271 | */ | |
648bdbee RM |
272 | for (i = 0; i < curr_part; i++) { |
273 | u64 next_part_offset = (i < curr_part - 1) ? | |
274 | parts[i + 1].offset : master->size; | |
275 | ||
276 | parts[i].size = next_part_offset - parts[i].offset; | |
b522d7b0 RM |
277 | } |
278 | ||
279 | /* If there was TRX parse it now */ | |
89a0d9a9 RM |
280 | for (i = 0; i < trx_num; i++) { |
281 | struct mtd_partition *trx = &parts[trx_parts[i]]; | |
282 | ||
99352afe RM |
283 | if (i == bcm47xxpart_bootpartition()) |
284 | trx->types = trx_types; | |
285 | else | |
89a0d9a9 | 286 | trx->name = "failsafe"; |
648bdbee | 287 | } |
3cf7f131 RM |
288 | |
289 | *pparts = parts; | |
290 | return curr_part; | |
291 | }; | |
292 | ||
293 | static struct mtd_part_parser bcm47xxpart_mtd_parser = { | |
3cf7f131 RM |
294 | .parse_fn = bcm47xxpart_parse, |
295 | .name = "bcm47xxpart", | |
296 | }; | |
b8f70bad | 297 | module_mtd_part_parser(bcm47xxpart_mtd_parser); |
3cf7f131 RM |
298 | |
299 | MODULE_LICENSE("GPL"); | |
300 | MODULE_DESCRIPTION("MTD partitioning for BCM47XX flash memories"); |