1 /*
2 * BCM63XX CFE image tag parser
3 *
4 * Copyright © 2006-2008 Florian Fainelli <florian@openwrt.org>
5 * Mike Albon <malbon@openwrt.org>
6 * Copyright © 2009-2010 Daniel Dickinson <openwrt@cshore.neomailbox.net>
7 * Copyright © 2011-2013 Jonas Gorski <jonas.gorski@gmail.com>
8 *
9 * This program is free software; you can redistribute it and/or modify
10 * it under the terms of the GNU General Public License as published by
11 * the Free Software Foundation; either version 2 of the License, or
12 * (at your option) any later version.
13 *
14 * This program is distributed in the hope that it will be useful,
15 * but WITHOUT ANY WARRANTY; without even the implied warranty of
16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17 * GNU General Public License for more details.
18 *
19 * You should have received a copy of the GNU General Public License
20 * along with this program; if not, write to the Free Software
21 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
22 *
23 */
24
25 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
26
27 #include <linux/bcm963xx_nvram.h>
28 #include <linux/bcm963xx_tag.h>
29 #include <linux/crc32.h>
30 #include <linux/module.h>
31 #include <linux/kernel.h>
32 #include <linux/sizes.h>
33 #include <linux/slab.h>
34 #include <linux/vmalloc.h>
35 #include <linux/mtd/mtd.h>
36 #include <linux/mtd/partitions.h>
37
38 #define BCM963XX_CFE_BLOCK_SIZE SZ_64K /* always at least 64KiB */
39
40 #define BCM963XX_CFE_MAGIC_OFFSET 0x4e0
41 #define BCM963XX_CFE_VERSION_OFFSET 0x570
42 #define BCM963XX_NVRAM_OFFSET 0x580
43
44 /* Ensure strings read from flash structs are null terminated */
45 #define STR_NULL_TERMINATE(x) \
46 do { char *_str = (x); _str[sizeof(x) - 1] = 0; } while (0)
47
bcm63xx_detect_cfe(struct mtd_info * master)48 static int bcm63xx_detect_cfe(struct mtd_info *master)
49 {
50 char buf[9];
51 int ret;
52 size_t retlen;
53
54 ret = mtd_read(master, BCM963XX_CFE_VERSION_OFFSET, 5, &retlen,
55 (void *)buf);
56 buf[retlen] = 0;
57
58 if (ret)
59 return ret;
60
61 if (strncmp("cfe-v", buf, 5) == 0)
62 return 0;
63
64 /* very old CFE's do not have the cfe-v string, so check for magic */
65 ret = mtd_read(master, BCM963XX_CFE_MAGIC_OFFSET, 8, &retlen,
66 (void *)buf);
67 buf[retlen] = 0;
68
69 return strncmp("CFE1CFE1", buf, 8);
70 }
71
bcm63xx_read_nvram(struct mtd_info * master,struct bcm963xx_nvram * nvram)72 static int bcm63xx_read_nvram(struct mtd_info *master,
73 struct bcm963xx_nvram *nvram)
74 {
75 u32 actual_crc, expected_crc;
76 size_t retlen;
77 int ret;
78
79 /* extract nvram data */
80 ret = mtd_read(master, BCM963XX_NVRAM_OFFSET, BCM963XX_NVRAM_V5_SIZE,
81 &retlen, (void *)nvram);
82 if (ret)
83 return ret;
84
85 ret = bcm963xx_nvram_checksum(nvram, &expected_crc, &actual_crc);
86 if (ret)
87 pr_warn("nvram checksum failed, contents may be invalid (expected %08x, got %08x)\n",
88 expected_crc, actual_crc);
89
90 if (!nvram->psi_size)
91 nvram->psi_size = BCM963XX_DEFAULT_PSI_SIZE;
92
93 return 0;
94 }
95
bcm63xx_read_image_tag(struct mtd_info * master,const char * name,loff_t tag_offset,struct bcm_tag * buf)96 static int bcm63xx_read_image_tag(struct mtd_info *master, const char *name,
97 loff_t tag_offset, struct bcm_tag *buf)
98 {
99 int ret;
100 size_t retlen;
101 u32 computed_crc;
102
103 ret = mtd_read(master, tag_offset, sizeof(*buf), &retlen, (void *)buf);
104 if (ret)
105 return ret;
106
107 if (retlen != sizeof(*buf))
108 return -EIO;
109
110 computed_crc = crc32_le(IMAGETAG_CRC_START, (u8 *)buf,
111 offsetof(struct bcm_tag, header_crc));
112 if (computed_crc == buf->header_crc) {
113 STR_NULL_TERMINATE(buf->board_id);
114 STR_NULL_TERMINATE(buf->tag_version);
115
116 pr_info("%s: CFE image tag found at 0x%llx with version %s, board type %s\n",
117 name, tag_offset, buf->tag_version, buf->board_id);
118
119 return 0;
120 }
121
122 pr_warn("%s: CFE image tag at 0x%llx CRC invalid (expected %08x, actual %08x)\n",
123 name, tag_offset, buf->header_crc, computed_crc);
124 return 1;
125 }
126
bcm63xx_parse_cfe_nor_partitions(struct mtd_info * master,const struct mtd_partition ** pparts,struct bcm963xx_nvram * nvram)127 static int bcm63xx_parse_cfe_nor_partitions(struct mtd_info *master,
128 const struct mtd_partition **pparts, struct bcm963xx_nvram *nvram)
129 {
130 /* CFE, NVRAM and global Linux are always present */
131 int nrparts = 3, curpart = 0;
132 struct bcm_tag *buf = NULL;
133 struct mtd_partition *parts;
134 int ret;
135 unsigned int rootfsaddr, kerneladdr, spareaddr;
136 unsigned int rootfslen, kernellen, sparelen, totallen;
137 unsigned int cfelen, nvramlen;
138 unsigned int cfe_erasesize;
139 int i;
140 bool rootfs_first = false;
141
142 cfe_erasesize = max_t(uint32_t, master->erasesize,
143 BCM963XX_CFE_BLOCK_SIZE);
144
145 cfelen = cfe_erasesize;
146 nvramlen = nvram->psi_size * SZ_1K;
147 nvramlen = roundup(nvramlen, cfe_erasesize);
148
149 buf = vmalloc(sizeof(struct bcm_tag));
150 if (!buf)
151 return -ENOMEM;
152
153 /* Get the tag */
154 ret = bcm63xx_read_image_tag(master, "rootfs", cfelen, buf);
155 if (!ret) {
156 STR_NULL_TERMINATE(buf->flash_image_start);
157 if (kstrtouint(buf->flash_image_start, 10, &rootfsaddr) ||
158 rootfsaddr < BCM963XX_EXTENDED_SIZE) {
159 pr_err("invalid rootfs address: %*ph\n",
160 (int)sizeof(buf->flash_image_start),
161 buf->flash_image_start);
162 goto invalid_tag;
163 }
164
165 STR_NULL_TERMINATE(buf->kernel_address);
166 if (kstrtouint(buf->kernel_address, 10, &kerneladdr) ||
167 kerneladdr < BCM963XX_EXTENDED_SIZE) {
168 pr_err("invalid kernel address: %*ph\n",
169 (int)sizeof(buf->kernel_address),
170 buf->kernel_address);
171 goto invalid_tag;
172 }
173
174 STR_NULL_TERMINATE(buf->kernel_length);
175 if (kstrtouint(buf->kernel_length, 10, &kernellen)) {
176 pr_err("invalid kernel length: %*ph\n",
177 (int)sizeof(buf->kernel_length),
178 buf->kernel_length);
179 goto invalid_tag;
180 }
181
182 STR_NULL_TERMINATE(buf->total_length);
183 if (kstrtouint(buf->total_length, 10, &totallen)) {
184 pr_err("invalid total length: %*ph\n",
185 (int)sizeof(buf->total_length),
186 buf->total_length);
187 goto invalid_tag;
188 }
189
190 kerneladdr = kerneladdr - BCM963XX_EXTENDED_SIZE;
191 rootfsaddr = rootfsaddr - BCM963XX_EXTENDED_SIZE;
192 spareaddr = roundup(totallen, master->erasesize) + cfelen;
193
194 if (rootfsaddr < kerneladdr) {
195 /* default Broadcom layout */
196 rootfslen = kerneladdr - rootfsaddr;
197 rootfs_first = true;
198 } else {
199 /* OpenWrt layout */
200 rootfsaddr = kerneladdr + kernellen;
201 rootfslen = spareaddr - rootfsaddr;
202 }
203 } else if (ret > 0) {
204 invalid_tag:
205 kernellen = 0;
206 rootfslen = 0;
207 rootfsaddr = 0;
208 spareaddr = cfelen;
209 } else {
210 goto out;
211 }
212 sparelen = master->size - spareaddr - nvramlen;
213
214 /* Determine number of partitions */
215 if (rootfslen > 0)
216 nrparts++;
217
218 if (kernellen > 0)
219 nrparts++;
220
221 parts = kzalloc(sizeof(*parts) * nrparts + 10 * nrparts, GFP_KERNEL);
222 if (!parts) {
223 ret = -ENOMEM;
224 goto out;
225 }
226
227 /* Start building partition list */
228 parts[curpart].name = "CFE";
229 parts[curpart].offset = 0;
230 parts[curpart].size = cfelen;
231 curpart++;
232
233 if (kernellen > 0) {
234 int kernelpart = curpart;
235
236 if (rootfslen > 0 && rootfs_first)
237 kernelpart++;
238 parts[kernelpart].name = "kernel";
239 parts[kernelpart].offset = kerneladdr;
240 parts[kernelpart].size = kernellen;
241 curpart++;
242 }
243
244 if (rootfslen > 0) {
245 int rootfspart = curpart;
246
247 if (kernellen > 0 && rootfs_first)
248 rootfspart--;
249 parts[rootfspart].name = "rootfs";
250 parts[rootfspart].offset = rootfsaddr;
251 parts[rootfspart].size = rootfslen;
252 if (sparelen > 0 && !rootfs_first)
253 parts[rootfspart].size += sparelen;
254 curpart++;
255 }
256
257 parts[curpart].name = "nvram";
258 parts[curpart].offset = master->size - nvramlen;
259 parts[curpart].size = nvramlen;
260 curpart++;
261
262 /* Global partition "linux" to make easy firmware upgrade */
263 parts[curpart].name = "linux";
264 parts[curpart].offset = cfelen;
265 parts[curpart].size = master->size - cfelen - nvramlen;
266
267 for (i = 0; i < nrparts; i++)
268 pr_info("Partition %d is %s offset %llx and length %llx\n", i,
269 parts[i].name, parts[i].offset, parts[i].size);
270
271 pr_info("Spare partition is offset %x and length %x\n", spareaddr,
272 sparelen);
273
274 *pparts = parts;
275 ret = 0;
276
277 out:
278 vfree(buf);
279
280 if (ret)
281 return ret;
282
283 return nrparts;
284 }
285
bcm63xx_parse_cfe_partitions(struct mtd_info * master,const struct mtd_partition ** pparts,struct mtd_part_parser_data * data)286 static int bcm63xx_parse_cfe_partitions(struct mtd_info *master,
287 const struct mtd_partition **pparts,
288 struct mtd_part_parser_data *data)
289 {
290 struct bcm963xx_nvram *nvram = NULL;
291 int ret;
292
293 if (bcm63xx_detect_cfe(master))
294 return -EINVAL;
295
296 nvram = vzalloc(sizeof(*nvram));
297 if (!nvram)
298 return -ENOMEM;
299
300 ret = bcm63xx_read_nvram(master, nvram);
301 if (ret)
302 goto out;
303
304 if (!mtd_type_is_nand(master))
305 ret = bcm63xx_parse_cfe_nor_partitions(master, pparts, nvram);
306 else
307 ret = -EINVAL;
308
309 out:
310 vfree(nvram);
311 return ret;
312 };
313
314 static struct mtd_part_parser bcm63xx_cfe_parser = {
315 .parse_fn = bcm63xx_parse_cfe_partitions,
316 .name = "bcm63xxpart",
317 };
318 module_mtd_part_parser(bcm63xx_cfe_parser);
319
320 MODULE_LICENSE("GPL");
321 MODULE_AUTHOR("Daniel Dickinson <openwrt@cshore.neomailbox.net>");
322 MODULE_AUTHOR("Florian Fainelli <florian@openwrt.org>");
323 MODULE_AUTHOR("Mike Albon <malbon@openwrt.org>");
324 MODULE_AUTHOR("Jonas Gorski <jonas.gorski@gmail.com");
325 MODULE_DESCRIPTION("MTD partitioning for BCM63XX CFE bootloaders");
326
