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1// SPDX-License-Identifier: GPL-2.0-only2/*3 * Parser for TRX format partitions4 *5 * Copyright (C) 2012 - 2017 Rafał Miłecki <rafal@milecki.pl>6 */7 8#include <linux/module.h>9#include <linux/slab.h>10#include <linux/mtd/mtd.h>11#include <linux/mtd/partitions.h>12 13#define TRX_PARSER_MAX_PARTS 414 15/* Magics */16#define TRX_MAGIC 0x3052444817#define UBI_EC_MAGIC 0x23494255 /* UBI# */18 19struct trx_header {20 uint32_t magic;21 uint32_t length;22 uint32_t crc32;23 uint16_t flags;24 uint16_t version;25 uint32_t offset[3];26} __packed;27 28static const char *parser_trx_data_part_name(struct mtd_info *master,29 size_t offset)30{31 uint32_t buf;32 size_t bytes_read;33 int err;34 35 err = mtd_read(master, offset, sizeof(buf), &bytes_read,36 (uint8_t *)&buf);37 if (err && !mtd_is_bitflip(err)) {38 pr_err("mtd_read error while parsing (offset: 0x%zX): %d\n",39 offset, err);40 goto out_default;41 }42 43 if (buf == UBI_EC_MAGIC)44 return "ubi";45 46out_default:47 return "rootfs";48}49 50static int parser_trx_parse(struct mtd_info *mtd,51 const struct mtd_partition **pparts,52 struct mtd_part_parser_data *data)53{54 struct device_node *np = mtd_get_of_node(mtd);55 struct mtd_partition *parts;56 struct mtd_partition *part;57 struct trx_header trx;58 size_t bytes_read;59 uint8_t curr_part = 0, i = 0;60 uint32_t trx_magic = TRX_MAGIC;61 int err;62 63 /* Get different magic from device tree if specified */64 err = of_property_read_u32(np, "brcm,trx-magic", &trx_magic);65 if (err != 0 && err != -EINVAL)66 pr_err("failed to parse \"brcm,trx-magic\" DT attribute, using default: %d\n", err);67 68 parts = kcalloc(TRX_PARSER_MAX_PARTS, sizeof(struct mtd_partition),69 GFP_KERNEL);70 if (!parts)71 return -ENOMEM;72 73 err = mtd_read(mtd, 0, sizeof(trx), &bytes_read, (uint8_t *)&trx);74 if (err) {75 pr_err("MTD reading error: %d\n", err);76 kfree(parts);77 return err;78 }79 80 if (trx.magic != trx_magic) {81 kfree(parts);82 return -ENOENT;83 }84 85 /* We have LZMA loader if there is address in offset[2] */86 if (trx.offset[2]) {87 part = &parts[curr_part++];88 part->name = "loader";89 part->offset = trx.offset[i];90 i++;91 }92 93 if (trx.offset[i]) {94 part = &parts[curr_part++];95 part->name = "linux";96 part->offset = trx.offset[i];97 i++;98 }99 100 if (trx.offset[i]) {101 part = &parts[curr_part++];102 part->name = parser_trx_data_part_name(mtd, trx.offset[i]);103 part->offset = trx.offset[i];104 i++;105 }106 107 /*108 * Assume that every partition ends at the beginning of the one it is109 * followed by.110 */111 for (i = 0; i < curr_part; i++) {112 u64 next_part_offset = (i < curr_part - 1) ?113 parts[i + 1].offset : mtd->size;114 115 parts[i].size = next_part_offset - parts[i].offset;116 }117 118 *pparts = parts;119 return i;120};121 122static const struct of_device_id mtd_parser_trx_of_match_table[] = {123 { .compatible = "brcm,trx" },124 {},125};126MODULE_DEVICE_TABLE(of, mtd_parser_trx_of_match_table);127 128static struct mtd_part_parser mtd_parser_trx = {129 .parse_fn = parser_trx_parse,130 .name = "trx",131 .of_match_table = mtd_parser_trx_of_match_table,132};133module_mtd_part_parser(mtd_parser_trx);134 135MODULE_LICENSE("GPL v2");136MODULE_DESCRIPTION("Parser for TRX format partitions");137