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_nvram.h>
14#include <linux/bcm963xx_tag.h>
15#include <linux/crc32.h>
16#include <linux/module.h>
17#include <linux/kernel.h>
18#include <linux/sizes.h>
19#include <linux/slab.h>
20#include <linux/vmalloc.h>
21#include <linux/mtd/mtd.h>
22#include <linux/mtd/partitions.h>
23#include <linux/of.h>
24
25#ifdef CONFIG_MIPS
26#include <asm/bootinfo.h>
27#include <asm/fw/cfe/cfe_api.h>
28#endif /* CONFIG_MIPS */
29
30#define BCM963XX_CFE_BLOCK_SIZE SZ_64K /* always at least 64KiB */
31
32#define BCM963XX_CFE_MAGIC_OFFSET 0x4e0
33#define BCM963XX_CFE_VERSION_OFFSET 0x570
34#define BCM963XX_NVRAM_OFFSET 0x580
35
36/* Ensure strings read from flash structs are null terminated */
37#define STR_NULL_TERMINATE(x) \
38 do { char *_str = (x); _str[sizeof(x) - 1] = 0; } while (0)
39
40static inline int bcm63xx_detect_cfe(void)
41{
42 int ret = 0;
43
44#ifdef CONFIG_MIPS
45 ret = (fw_arg3 == CFE_EPTSEAL);
46#endif /* CONFIG_MIPS */
47
48 return ret;
49}
50
51static int bcm63xx_read_nvram(struct mtd_info *master,
52 struct bcm963xx_nvram *nvram)
53{
54 u32 actual_crc, expected_crc;
55 size_t retlen;
56 int ret;
57
58 /* extract nvram data */
59 ret = mtd_read(mtd: master, BCM963XX_NVRAM_OFFSET, BCM963XX_NVRAM_V5_SIZE,
60 retlen: &retlen, buf: (void *)nvram);
61 if (ret)
62 return ret;
63
64 ret = bcm963xx_nvram_checksum(nvram, expected_out: &expected_crc, actual_out: &actual_crc);
65 if (ret)
66 pr_warn("nvram checksum failed, contents may be invalid (expected %08x, got %08x)\n",
67 expected_crc, actual_crc);
68
69 if (!nvram->psi_size)
70 nvram->psi_size = BCM963XX_DEFAULT_PSI_SIZE;
71
72 return 0;
73}
74
75static const char * const bcm63xx_cfe_part_types[] = {
76 "bcm963xx-imagetag",
77 NULL,
78};
79
80static int bcm63xx_parse_cfe_nor_partitions(struct mtd_info *master,
81 const struct mtd_partition **pparts, struct bcm963xx_nvram *nvram)
82{
83 struct mtd_partition *parts;
84 int nrparts = 3, curpart = 0;
85 unsigned int cfelen, nvramlen;
86 unsigned int cfe_erasesize;
87 int i;
88
89 cfe_erasesize = max_t(uint32_t, master->erasesize,
90 BCM963XX_CFE_BLOCK_SIZE);
91
92 cfelen = cfe_erasesize;
93 nvramlen = nvram->psi_size * SZ_1K;
94 nvramlen = roundup(nvramlen, cfe_erasesize);
95
96 parts = kzalloc(sizeof(*parts) * nrparts + 10 * nrparts, GFP_KERNEL);
97 if (!parts)
98 return -ENOMEM;
99
100 /* Start building partition list */
101 parts[curpart].name = "CFE";
102 parts[curpart].offset = 0;
103 parts[curpart].size = cfelen;
104 curpart++;
105
106 parts[curpart].name = "nvram";
107 parts[curpart].offset = master->size - nvramlen;
108 parts[curpart].size = nvramlen;
109 curpart++;
110
111 /* Global partition "linux" to make easy firmware upgrade */
112 parts[curpart].name = "linux";
113 parts[curpart].offset = cfelen;
114 parts[curpart].size = master->size - cfelen - nvramlen;
115 parts[curpart].types = bcm63xx_cfe_part_types;
116
117 for (i = 0; i < nrparts; i++)
118 pr_info("Partition %d is %s offset %llx and length %llx\n", i,
119 parts[i].name, parts[i].offset, parts[i].size);
120
121 *pparts = parts;
122
123 return nrparts;
124}
125
126static int bcm63xx_parse_cfe_partitions(struct mtd_info *master,
127 const struct mtd_partition **pparts,
128 struct mtd_part_parser_data *data)
129{
130 struct bcm963xx_nvram *nvram = NULL;
131 int ret;
132
133 if (!bcm63xx_detect_cfe())
134 return -EINVAL;
135
136 nvram = vzalloc(sizeof(*nvram));
137 if (!nvram)
138 return -ENOMEM;
139
140 ret = bcm63xx_read_nvram(master, nvram);
141 if (ret)
142 goto out;
143
144 if (!mtd_type_is_nand(mtd: master))
145 ret = bcm63xx_parse_cfe_nor_partitions(master, pparts, nvram);
146 else
147 ret = -EINVAL;
148
149out:
150 vfree(addr: nvram);
151 return ret;
152};
153
154static const struct of_device_id parse_bcm63xx_cfe_match_table[] = {
155 { .compatible = "brcm,bcm963xx-cfe-nor-partitions" },
156 {},
157};
158MODULE_DEVICE_TABLE(of, parse_bcm63xx_cfe_match_table);
159
160static struct mtd_part_parser bcm63xx_cfe_parser = {
161 .parse_fn = bcm63xx_parse_cfe_partitions,
162 .name = "bcm63xxpart",
163 .of_match_table = parse_bcm63xx_cfe_match_table,
164};
165module_mtd_part_parser(bcm63xx_cfe_parser);
166
167MODULE_AUTHOR("Daniel Dickinson <openwrt@cshore.neomailbox.net>");
168MODULE_AUTHOR("Florian Fainelli <florian@openwrt.org>");
169MODULE_AUTHOR("Mike Albon <malbon@openwrt.org>");
170MODULE_AUTHOR("Jonas Gorski <jonas.gorski@gmail.com");
171MODULE_DESCRIPTION("MTD partitioning for BCM63XX CFE bootloaders");
172

source code of linux/drivers/mtd/parsers/bcm63xxpart.c