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Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
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linux
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 © 2011-2012 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/crc32.h>
28#include <linux/module.h>
29#include <linux/kernel.h>
30#include <linux/slab.h>
31#include <linux/vmalloc.h>
32#include <linux/mtd/mtd.h>
33#include <linux/mtd/partitions.h>
34
35#include <asm/mach-bcm63xx/bcm963xx_tag.h>
36#include <asm/mach-bcm63xx/board_bcm963xx.h>
37
38#define BCM63XX_EXTENDED_SIZE 0xBFC00000 /* Extended flash address */
39
40#define BCM63XX_MIN_CFE_SIZE 0x10000 /* always at least 64KiB */
41#define BCM63XX_MIN_NVRAM_SIZE 0x10000 /* always at least 64KiB */
42
43#define BCM63XX_CFE_MAGIC_OFFSET 0x4e0
44
45static int bcm63xx_detect_cfe(struct mtd_info *master)
46{
47 char buf[9];
48 int ret;
49 size_t retlen;
50
51 ret = mtd_read(master, BCM963XX_CFE_VERSION_OFFSET, 5, &retlen,
52 (void *)buf);
53 buf[retlen] = 0;
54
55 if (ret)
56 return ret;
57
58 if (strncmp("cfe-v", buf, 5) == 0)
59 return 0;
60
61 /* very old CFE's do not have the cfe-v string, so check for magic */
62 ret = mtd_read(master, BCM63XX_CFE_MAGIC_OFFSET, 8, &retlen,
63 (void *)buf);
64 buf[retlen] = 0;
65
66 return strncmp("CFE1CFE1", buf, 8);
67}
68
69static int bcm63xx_parse_cfe_partitions(struct mtd_info *master,
70 struct mtd_partition **pparts,
71 struct mtd_part_parser_data *data)
72{
73 /* CFE, NVRAM and global Linux are always present */
74 int nrparts = 3, curpart = 0;
75 struct bcm_tag *buf;
76 struct mtd_partition *parts;
77 int ret;
78 size_t retlen;
79 unsigned int rootfsaddr, kerneladdr, spareaddr;
80 unsigned int rootfslen, kernellen, sparelen, totallen;
81 unsigned int cfelen, nvramlen;
82 int namelen = 0;
83 int i;
84 u32 computed_crc;
85 bool rootfs_first = false;
86
87 if (bcm63xx_detect_cfe(master))
88 return -EINVAL;
89
90 cfelen = max_t(uint32_t, master->erasesize, BCM63XX_MIN_CFE_SIZE);
91 nvramlen = max_t(uint32_t, master->erasesize, BCM63XX_MIN_NVRAM_SIZE);
92
93 /* Allocate memory for buffer */
94 buf = vmalloc(sizeof(struct bcm_tag));
95 if (!buf)
96 return -ENOMEM;
97
98 /* Get the tag */
99 ret = mtd_read(master, cfelen, sizeof(struct bcm_tag), &retlen,
100 (void *)buf);
101
102 if (retlen != sizeof(struct bcm_tag)) {
103 vfree(buf);
104 return -EIO;
105 }
106
107 computed_crc = crc32_le(IMAGETAG_CRC_START, (u8 *)buf,
108 offsetof(struct bcm_tag, header_crc));
109 if (computed_crc == buf->header_crc) {
110 char *boardid = &(buf->board_id[0]);
111 char *tagversion = &(buf->tag_version[0]);
112
113 sscanf(buf->flash_image_start, "%u", &rootfsaddr);
114 sscanf(buf->kernel_address, "%u", &kerneladdr);
115 sscanf(buf->kernel_length, "%u", &kernellen);
116 sscanf(buf->total_length, "%u", &totallen);
117
118 pr_info("CFE boot tag found with version %s and board type %s\n",
119 tagversion, boardid);
120
121 kerneladdr = kerneladdr - BCM63XX_EXTENDED_SIZE;
122 rootfsaddr = rootfsaddr - BCM63XX_EXTENDED_SIZE;
123 spareaddr = roundup(totallen, master->erasesize) + cfelen;
124 sparelen = master->size - spareaddr - nvramlen;
125
126 if (rootfsaddr < kerneladdr) {
127 /* default Broadcom layout */
128 rootfslen = kerneladdr - rootfsaddr;
129 rootfs_first = true;
130 } else {
131 /* OpenWrt layout */
132 rootfsaddr = kerneladdr + kernellen;
133 rootfslen = spareaddr - rootfsaddr;
134 }
135 } else {
136 pr_warn("CFE boot tag CRC invalid (expected %08x, actual %08x)\n",
137 buf->header_crc, computed_crc);
138 kernellen = 0;
139 rootfslen = 0;
140 rootfsaddr = 0;
141 spareaddr = cfelen;
142 sparelen = master->size - cfelen - nvramlen;
143 }
144
145 /* Determine number of partitions */
146 namelen = 8;
147 if (rootfslen > 0) {
148 nrparts++;
149 namelen += 6;
150 }
151 if (kernellen > 0) {
152 nrparts++;
153 namelen += 6;
154 }
155
156 /* Ask kernel for more memory */
157 parts = kzalloc(sizeof(*parts) * nrparts + 10 * nrparts, GFP_KERNEL);
158 if (!parts) {
159 vfree(buf);
160 return -ENOMEM;
161 }
162
163 /* Start building partition list */
164 parts[curpart].name = "CFE";
165 parts[curpart].offset = 0;
166 parts[curpart].size = cfelen;
167 curpart++;
168
169 if (kernellen > 0) {
170 int kernelpart = curpart;
171
172 if (rootfslen > 0 && rootfs_first)
173 kernelpart++;
174 parts[kernelpart].name = "kernel";
175 parts[kernelpart].offset = kerneladdr;
176 parts[kernelpart].size = kernellen;
177 curpart++;
178 }
179
180 if (rootfslen > 0) {
181 int rootfspart = curpart;
182
183 if (kernellen > 0 && rootfs_first)
184 rootfspart--;
185 parts[rootfspart].name = "rootfs";
186 parts[rootfspart].offset = rootfsaddr;
187 parts[rootfspart].size = rootfslen;
188 if (sparelen > 0 && !rootfs_first)
189 parts[rootfspart].size += sparelen;
190 curpart++;
191 }
192
193 parts[curpart].name = "nvram";
194 parts[curpart].offset = master->size - nvramlen;
195 parts[curpart].size = nvramlen;
196
197 /* Global partition "linux" to make easy firmware upgrade */
198 curpart++;
199 parts[curpart].name = "linux";
200 parts[curpart].offset = cfelen;
201 parts[curpart].size = master->size - cfelen - nvramlen;
202
203 for (i = 0; i < nrparts; i++)
204 pr_info("Partition %d is %s offset %lx and length %lx\n", i,
205 parts[i].name, (long unsigned int)(parts[i].offset),
206 (long unsigned int)(parts[i].size));
207
208 pr_info("Spare partition is offset %x and length %x\n", spareaddr,
209 sparelen);
210
211 *pparts = parts;
212 vfree(buf);
213
214 return nrparts;
215};
216
217static struct mtd_part_parser bcm63xx_cfe_parser = {
218 .owner = THIS_MODULE,
219 .parse_fn = bcm63xx_parse_cfe_partitions,
220 .name = "bcm63xxpart",
221};
222
223static int __init bcm63xx_cfe_parser_init(void)
224{
225 return register_mtd_parser(&bcm63xx_cfe_parser);
226}
227
228static void __exit bcm63xx_cfe_parser_exit(void)
229{
230 deregister_mtd_parser(&bcm63xx_cfe_parser);
231}
232
233module_init(bcm63xx_cfe_parser_init);
234module_exit(bcm63xx_cfe_parser_exit);
235
236MODULE_LICENSE("GPL");
237MODULE_AUTHOR("Daniel Dickinson <openwrt@cshore.neomailbox.net>");
238MODULE_AUTHOR("Florian Fainelli <florian@openwrt.org>");
239MODULE_AUTHOR("Mike Albon <malbon@openwrt.org>");
240MODULE_AUTHOR("Jonas Gorski <jonas.gorski@gmail.com");
241MODULE_DESCRIPTION("MTD partitioning for BCM63XX CFE bootloaders");