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(master, BCM963XX_NVRAM_OFFSET, BCM963XX_NVRAM_V5_SIZE,
 60			&retlen, (void *)nvram);
 61	if (ret)
 62		return ret;
 63
 64	ret = bcm963xx_nvram_checksum(nvram, &expected_crc, &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(master))
145		ret = bcm63xx_parse_cfe_nor_partitions(master, pparts, nvram);
146	else
147		ret = -EINVAL;
148
149out:
150	vfree(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");