1 | // SPDX-License-Identifier: GPL-2.0-or-later |
2 | /* |
3 | * BCM63XX CFE image tag parser |
4 | * |
5 | * Copyright © 2006-2008 Florian Fainelli <florian@openwrt.org> |
6 | * Mike Albon <malbon@openwrt.org> |
7 | * Copyright © 2009-2010 Daniel Dickinson <openwrt@cshore.neomailbox.net> |
8 | * Copyright © 2011-2013 Jonas Gorski <jonas.gorski@gmail.com> |
9 | */ |
10 | |
11 | #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt |
12 | |
13 | #include <linux/bcm963xx_tag.h> |
14 | #include <linux/crc32.h> |
15 | #include <linux/module.h> |
16 | #include <linux/kernel.h> |
17 | #include <linux/sizes.h> |
18 | #include <linux/slab.h> |
19 | #include <linux/vmalloc.h> |
20 | #include <linux/mtd/mtd.h> |
21 | #include <linux/mtd/partitions.h> |
22 | #include <linux/of.h> |
23 | |
24 | /* Ensure strings read from flash structs are null terminated */ |
25 | #define STR_NULL_TERMINATE(x) \ |
26 | do { char *_str = (x); _str[sizeof(x) - 1] = 0; } while (0) |
27 | |
28 | static int bcm963xx_read_imagetag(struct mtd_info *master, const char *name, |
29 | loff_t tag_offset, struct bcm_tag *buf) |
30 | { |
31 | int ret; |
32 | size_t retlen; |
33 | u32 computed_crc; |
34 | |
35 | ret = mtd_read(mtd: master, from: tag_offset, len: sizeof(*buf), retlen: &retlen, buf: (void *)buf); |
36 | if (ret) |
37 | return ret; |
38 | |
39 | if (retlen != sizeof(*buf)) |
40 | return -EIO; |
41 | |
42 | computed_crc = crc32_le(IMAGETAG_CRC_START, p: (u8 *)buf, |
43 | offsetof(struct bcm_tag, header_crc)); |
44 | if (computed_crc == buf->header_crc) { |
45 | STR_NULL_TERMINATE(buf->board_id); |
46 | STR_NULL_TERMINATE(buf->tag_version); |
47 | |
48 | pr_info("%s: CFE image tag found at 0x%llx with version %s, board type %s\n" , |
49 | name, tag_offset, buf->tag_version, buf->board_id); |
50 | |
51 | return 0; |
52 | } |
53 | |
54 | pr_warn("%s: CFE image tag at 0x%llx CRC invalid (expected %08x, actual %08x)\n" , |
55 | name, tag_offset, buf->header_crc, computed_crc); |
56 | return -EINVAL; |
57 | } |
58 | |
59 | static int bcm963xx_parse_imagetag_partitions(struct mtd_info *master, |
60 | const struct mtd_partition **pparts, |
61 | struct mtd_part_parser_data *data) |
62 | { |
63 | /* CFE, NVRAM and global Linux are always present */ |
64 | int nrparts = 0, curpart = 0; |
65 | struct bcm_tag *buf = NULL; |
66 | struct mtd_partition *parts; |
67 | int ret; |
68 | unsigned int rootfsaddr, kerneladdr, spareaddr, offset; |
69 | unsigned int rootfslen, kernellen, sparelen, totallen; |
70 | int i; |
71 | bool rootfs_first = false; |
72 | |
73 | buf = vmalloc(size: sizeof(struct bcm_tag)); |
74 | if (!buf) |
75 | return -ENOMEM; |
76 | |
77 | /* Get the tag */ |
78 | ret = bcm963xx_read_imagetag(master, name: "rootfs" , tag_offset: 0, buf); |
79 | if (!ret) { |
80 | STR_NULL_TERMINATE(buf->flash_image_start); |
81 | if (kstrtouint(s: buf->flash_image_start, base: 10, res: &rootfsaddr) || |
82 | rootfsaddr < BCM963XX_EXTENDED_SIZE) { |
83 | pr_err("invalid rootfs address: %*ph\n" , |
84 | (int)sizeof(buf->flash_image_start), |
85 | buf->flash_image_start); |
86 | ret = -EINVAL; |
87 | goto out; |
88 | } |
89 | |
90 | STR_NULL_TERMINATE(buf->kernel_address); |
91 | if (kstrtouint(s: buf->kernel_address, base: 10, res: &kerneladdr) || |
92 | kerneladdr < BCM963XX_EXTENDED_SIZE) { |
93 | pr_err("invalid kernel address: %*ph\n" , |
94 | (int)sizeof(buf->kernel_address), |
95 | buf->kernel_address); |
96 | ret = -EINVAL; |
97 | goto out; |
98 | } |
99 | |
100 | STR_NULL_TERMINATE(buf->kernel_length); |
101 | if (kstrtouint(s: buf->kernel_length, base: 10, res: &kernellen)) { |
102 | pr_err("invalid kernel length: %*ph\n" , |
103 | (int)sizeof(buf->kernel_length), |
104 | buf->kernel_length); |
105 | ret = -EINVAL; |
106 | goto out; |
107 | } |
108 | |
109 | STR_NULL_TERMINATE(buf->total_length); |
110 | if (kstrtouint(s: buf->total_length, base: 10, res: &totallen)) { |
111 | pr_err("invalid total length: %*ph\n" , |
112 | (int)sizeof(buf->total_length), |
113 | buf->total_length); |
114 | ret = -EINVAL; |
115 | goto out; |
116 | } |
117 | |
118 | /* |
119 | * Addresses are flash absolute, so convert to partition |
120 | * relative addresses. Assume either kernel or rootfs will |
121 | * directly follow the image tag. |
122 | */ |
123 | if (rootfsaddr < kerneladdr) |
124 | offset = rootfsaddr - sizeof(struct bcm_tag); |
125 | else |
126 | offset = kerneladdr - sizeof(struct bcm_tag); |
127 | |
128 | kerneladdr = kerneladdr - offset; |
129 | rootfsaddr = rootfsaddr - offset; |
130 | spareaddr = roundup(totallen, master->erasesize); |
131 | |
132 | if (rootfsaddr < kerneladdr) { |
133 | /* default Broadcom layout */ |
134 | rootfslen = kerneladdr - rootfsaddr; |
135 | rootfs_first = true; |
136 | } else { |
137 | /* OpenWrt layout */ |
138 | rootfsaddr = kerneladdr + kernellen; |
139 | rootfslen = spareaddr - rootfsaddr; |
140 | } |
141 | } else { |
142 | goto out; |
143 | } |
144 | sparelen = master->size - spareaddr; |
145 | |
146 | /* Determine number of partitions */ |
147 | if (rootfslen > 0) |
148 | nrparts++; |
149 | |
150 | if (kernellen > 0) |
151 | nrparts++; |
152 | |
153 | parts = kzalloc(size: sizeof(*parts) * nrparts + 10 * nrparts, GFP_KERNEL); |
154 | if (!parts) { |
155 | ret = -ENOMEM; |
156 | goto out; |
157 | } |
158 | |
159 | /* Start building partition list */ |
160 | if (kernellen > 0) { |
161 | int kernelpart = curpart; |
162 | |
163 | if (rootfslen > 0 && rootfs_first) |
164 | kernelpart++; |
165 | parts[kernelpart].name = "kernel" ; |
166 | parts[kernelpart].offset = kerneladdr; |
167 | parts[kernelpart].size = kernellen; |
168 | curpart++; |
169 | } |
170 | |
171 | if (rootfslen > 0) { |
172 | int rootfspart = curpart; |
173 | |
174 | if (kernellen > 0 && rootfs_first) |
175 | rootfspart--; |
176 | parts[rootfspart].name = "rootfs" ; |
177 | parts[rootfspart].offset = rootfsaddr; |
178 | parts[rootfspart].size = rootfslen; |
179 | if (sparelen > 0 && !rootfs_first) |
180 | parts[rootfspart].size += sparelen; |
181 | curpart++; |
182 | } |
183 | |
184 | for (i = 0; i < nrparts; i++) |
185 | pr_info("Partition %d is %s offset %llx and length %llx\n" , i, |
186 | parts[i].name, parts[i].offset, parts[i].size); |
187 | |
188 | pr_info("Spare partition is offset %x and length %x\n" , spareaddr, |
189 | sparelen); |
190 | |
191 | *pparts = parts; |
192 | ret = 0; |
193 | |
194 | out: |
195 | vfree(addr: buf); |
196 | |
197 | if (ret) |
198 | return ret; |
199 | |
200 | return nrparts; |
201 | } |
202 | |
203 | static const struct of_device_id parse_bcm963xx_imagetag_match_table[] = { |
204 | { .compatible = "brcm,bcm963xx-imagetag" }, |
205 | {}, |
206 | }; |
207 | MODULE_DEVICE_TABLE(of, parse_bcm963xx_imagetag_match_table); |
208 | |
209 | static struct mtd_part_parser bcm963xx_imagetag_parser = { |
210 | .parse_fn = bcm963xx_parse_imagetag_partitions, |
211 | .name = "bcm963xx-imagetag" , |
212 | .of_match_table = parse_bcm963xx_imagetag_match_table, |
213 | }; |
214 | module_mtd_part_parser(bcm963xx_imagetag_parser); |
215 | |
216 | MODULE_LICENSE("GPL" ); |
217 | MODULE_AUTHOR("Daniel Dickinson <openwrt@cshore.neomailbox.net>" ); |
218 | MODULE_AUTHOR("Florian Fainelli <florian@openwrt.org>" ); |
219 | MODULE_AUTHOR("Mike Albon <malbon@openwrt.org>" ); |
220 | MODULE_AUTHOR("Jonas Gorski <jonas.gorski@gmail.com>" ); |
221 | MODULE_DESCRIPTION("MTD parser for BCM963XX CFE Image Tag partitions" ); |
222 | |