openwrtv3/target/linux/generic/files/drivers/mtd/mtdsplit/mtdsplit_eva.c
Felix Fietkau 651083bbd9 kernel: mtdsplit: add support for EVA images
This allows splitting EVA images (usually found in fritz devices). The
firmware will be split into a kernel and a separate rootfs partition.

Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>

SVN-Revision: 48262
2016-01-17 10:41:08 +00:00

96 lines
2.2 KiB
C

/*
* Copyright (C) 2012 John Crispin <blogic@openwrt.org>
* Copyright (C) 2015 Martin Blumenstingl <martin.blumenstingl@googlemail.com>
*
* 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 "mtdsplit.h"
#define EVA_NR_PARTS 2
#define EVA_MAGIC 0xfeed1281
#define EVA_FOOTER_SIZE 0x18
#define EVA_DUMMY_SQUASHFS_SIZE 0x100
struct eva_image_header {
uint32_t magic;
uint32_t size;
};
static int mtdsplit_parse_eva(struct mtd_info *master,
struct mtd_partition **pparts,
struct mtd_part_parser_data *data)
{
struct mtd_partition *parts;
struct eva_image_header hdr;
size_t retlen;
unsigned long kernel_size, rootfs_offset;
int err;
err = mtd_read(master, 0, sizeof(hdr), &retlen, (void *) &hdr);
if (err)
return err;
if (retlen != sizeof(hdr))
return -EIO;
if (le32_to_cpu(hdr.magic) != EVA_MAGIC)
return -EINVAL;
kernel_size = le32_to_cpu(hdr.size) + EVA_FOOTER_SIZE;
/* rootfs starts at the next 0x10000 boundary: */
rootfs_offset = round_up(kernel_size, 0x10000);
/* skip the dummy EVA squashfs partition (with wrong endianness): */
rootfs_offset += EVA_DUMMY_SQUASHFS_SIZE;
if (rootfs_offset >= master->size)
return -EINVAL;
err = mtd_check_rootfs_magic(master, rootfs_offset);
if (err)
return err;
parts = kzalloc(EVA_NR_PARTS * sizeof(*parts), GFP_KERNEL);
if (!parts)
return -ENOMEM;
parts[0].name = KERNEL_PART_NAME;
parts[0].offset = 0;
parts[0].size = kernel_size;
parts[1].name = ROOTFS_PART_NAME;
parts[1].offset = rootfs_offset;
parts[1].size = master->size - rootfs_offset;
*pparts = parts;
return EVA_NR_PARTS;
}
static struct mtd_part_parser mtdsplit_eva_parser = {
.owner = THIS_MODULE,
.name = "eva-fw",
.parse_fn = mtdsplit_parse_eva,
.type = MTD_PARSER_TYPE_FIRMWARE,
};
static int __init mtdsplit_eva_init(void)
{
register_mtd_parser(&mtdsplit_eva_parser);
return 0;
}
subsys_initcall(mtdsplit_eva_init);