drivers/mtd/parsers/bcm63xxpart.c

   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
  40 static 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
  51 static 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
  75 static const char * const bcm63xx_cfe_part_types[] = {
  76         "bcm963xx-imagetag",
  77         NULL,
  78 };
  79
  80 static 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
 126 static 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
 149 out:
 150         vfree(nvram);
 151         return ret;
 152 };
 153
 154 static const struct of_device_id parse_bcm63xx_cfe_match_table[] = {
 155         { .compatible = "brcm,bcm963xx-cfe-nor-partitions" },
 156         {},
 157 };
 158 MODULE_DEVICE_TABLE(of, parse_bcm63xx_cfe_match_table);
 159
 160 static 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 };
 165 module_mtd_part_parser(bcm63xx_cfe_parser);
 166
 167 MODULE_LICENSE("GPL");
 168 MODULE_AUTHOR("Daniel Dickinson <openwrt@cshore.neomailbox.net>");
 169 MODULE_AUTHOR("Florian Fainelli <florian@openwrt.org>");
 170 MODULE_AUTHOR("Mike Albon <malbon@openwrt.org>");
 171 MODULE_AUTHOR("Jonas Gorski <jonas.gorski@gmail.com");
 172 MODULE_DESCRIPTION("MTD partitioning for BCM63XX CFE bootloaders");