| /* |
| * Copyright (C) 2013 Gabor Juhos <juhosg@openwrt.org> |
| * |
| * This program is free software; you can redistribute it and/or modify it |
| * under the terms of the GNU General Public License version 2 as published |
| * by the Free Software Foundation. |
| * |
| */ |
| |
| #include <linux/module.h> |
| #include <linux/init.h> |
| #include <linux/kernel.h> |
| #include <linux/slab.h> |
| #include <linux/mtd/mtd.h> |
| #include <linux/mtd/partitions.h> |
| #include <linux/byteorder/generic.h> |
| #include <linux/of.h> |
| |
| #include "mtdsplit.h" |
| |
| #define SEAMA_MAGIC 0x5EA3A417 |
| #define SEAMA_NR_PARTS 2 |
| #define SEAMA_MIN_ROOTFS_OFFS 0x80000 /* 512KiB */ |
| |
| struct seama_header { |
| __be32 magic; /* should always be SEAMA_MAGIC. */ |
| __be16 reserved; /* reserved for */ |
| __be16 metasize; /* size of the META data */ |
| __be32 size; /* size of the image */ |
| u8 md5[16]; /* digest */ |
| }; |
| |
| static int mtdsplit_parse_seama(struct mtd_info *master, |
| const struct mtd_partition **pparts, |
| struct mtd_part_parser_data *data) |
| { |
| struct seama_header hdr; |
| size_t hdr_len, retlen, kernel_ent_size; |
| size_t rootfs_offset; |
| struct mtd_partition *parts; |
| enum mtdsplit_part_type type; |
| int err; |
| |
| hdr_len = sizeof(hdr); |
| err = mtd_read(master, 0, hdr_len, &retlen, (void *) &hdr); |
| if (err) |
| return err; |
| |
| if (retlen != hdr_len) |
| return -EIO; |
| |
| /* sanity checks */ |
| if (be32_to_cpu(hdr.magic) != SEAMA_MAGIC) |
| return -EINVAL; |
| |
| kernel_ent_size = hdr_len + be32_to_cpu(hdr.size) + |
| be16_to_cpu(hdr.metasize); |
| if (kernel_ent_size > master->size) |
| return -EINVAL; |
| |
| /* Check for the rootfs right after Seama entity with a kernel. */ |
| err = mtd_check_rootfs_magic(master, kernel_ent_size, &type); |
| if (!err) { |
| rootfs_offset = kernel_ent_size; |
| } else { |
| /* |
| * On some devices firmware entity might contain both: kernel |
| * and rootfs. We can't determine kernel size so we just have to |
| * look for rootfs magic. |
| * Start the search from an arbitrary offset. |
| */ |
| err = mtd_find_rootfs_from(master, SEAMA_MIN_ROOTFS_OFFS, |
| master->size, &rootfs_offset, &type); |
| if (err) |
| return err; |
| } |
| |
| parts = kzalloc(SEAMA_NR_PARTS * sizeof(*parts), GFP_KERNEL); |
| if (!parts) |
| return -ENOMEM; |
| |
| parts[0].name = KERNEL_PART_NAME; |
| parts[0].offset = sizeof hdr + be16_to_cpu(hdr.metasize); |
| parts[0].size = rootfs_offset - parts[0].offset; |
| |
| if (type == MTDSPLIT_PART_TYPE_UBI) |
| parts[1].name = UBI_PART_NAME; |
| else |
| parts[1].name = ROOTFS_PART_NAME; |
| parts[1].offset = rootfs_offset; |
| parts[1].size = master->size - rootfs_offset; |
| |
| *pparts = parts; |
| return SEAMA_NR_PARTS; |
| } |
| |
| static const struct of_device_id mtdsplit_seama_of_match_table[] = { |
| { .compatible = "seama" }, |
| {}, |
| }; |
| MODULE_DEVICE_TABLE(of, mtdsplit_seama_of_match_table); |
| |
| static struct mtd_part_parser mtdsplit_seama_parser = { |
| .owner = THIS_MODULE, |
| .name = "seama-fw", |
| .of_match_table = mtdsplit_seama_of_match_table, |
| .parse_fn = mtdsplit_parse_seama, |
| .type = MTD_PARSER_TYPE_FIRMWARE, |
| }; |
| |
| static int __init mtdsplit_seama_init(void) |
| { |
| register_mtd_parser(&mtdsplit_seama_parser); |
| |
| return 0; |
| } |
| |
| subsys_initcall(mtdsplit_seama_init); |