kernel: add mtd split support for trx images

Signed-off-by: Felix Fietkau <nbd@openwrt.org>

SVN-Revision: 43809

3 files changed, 153 insertions, 0 deletions

diff --git a/target/linux/generic/files/drivers/mtd/mtdsplit/Kconfig b/target/linux/generic/files/drivers/mtd/mtdsplit/Kconfig
index 94775ea37f..fca6b48064 100644
--- a/target/linux/generic/files/drivers/mtd/mtdsplit/Kconfig
+++ b/target/linux/generic/files/drivers/mtd/mtdsplit/Kconfig
@@ -39,3 +39,8 @@ config MTD_SPLIT_TPLINK_FW
 	bool "TP-Link firmware parser"
 	depends on MTD_SPLIT_SUPPORT
 	select MTD_SPLIT
+
+config MTD_SPLIT_TRX_FW
+	bool "TRX image based firmware partition parser"
+	depends on MTD_SPLIT_SUPPORT
+	select MTD_SPLIT
diff --git a/target/linux/generic/files/drivers/mtd/mtdsplit/Makefile b/target/linux/generic/files/drivers/mtd/mtdsplit/Makefile
index bcb250b64d..12661ba151 100644
--- a/target/linux/generic/files/drivers/mtd/mtdsplit/Makefile
+++ b/target/linux/generic/files/drivers/mtd/mtdsplit/Makefile
@@ -4,3 +4,4 @@ obj-$(CONFIG_MTD_SPLIT_SQUASHFS_ROOT) += mtdsplit_squashfs.o
 obj-$(CONFIG_MTD_SPLIT_UIMAGE_FW) += mtdsplit_uimage.o
 obj-$(CONFIG_MTD_SPLIT_LZMA_FW) += mtdsplit_lzma.o
 obj-$(CONFIG_MTD_SPLIT_TPLINK_FW) += mtdsplit_tplink.o
+obj-$(CONFIG_MTD_SPLIT_TRX_FW) += mtdsplit_trx.o
diff --git a/target/linux/generic/files/drivers/mtd/mtdsplit/mtdsplit_trx.c b/target/linux/generic/files/drivers/mtd/mtdsplit/mtdsplit_trx.c
new file mode 100644
index 0000000000..6efffce196
--- /dev/null
+++ b/target/linux/generic/files/drivers/mtd/mtdsplit/mtdsplit_trx.c
@@ -0,0 +1,147 @@
+/*
+ *  Copyright (C) 2013 Gabor Juhos <juhosg@openwrt.org>
+ *  Copyright (C) 2014 Felix Fietkau <nbd@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.
+ *
+ */
+
+#define pr_fmt(fmt)	KBUILD_MODNAME ": " fmt
+
+#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 TRX_MAGIC   0x30524448  /* "HDR0" */
+
+struct trx_header {
+	__le32 magic;
+	__le32 len;
+	__le32 crc32;
+	__le32 flag_version;
+	__le32 offset[4];
+};
+
+static int
+read_trx_header(struct mtd_info *mtd, size_t offset,
+		   struct trx_header *header)
+{
+	size_t header_len;
+	size_t retlen;
+	int ret;
+
+	header_len = sizeof(*header);
+	ret = mtd_read(mtd, offset, header_len, &retlen,
+		       (unsigned char *) header);
+	if (ret) {
+		pr_debug("read error in \"%s\"\n", mtd->name);
+		return ret;
+	}
+
+	if (retlen != header_len) {
+		pr_debug("short read in \"%s\"\n", mtd->name);
+		return -EIO;
+	}
+
+	return 0;
+}
+
+static int
+mtdsplit_parse_trx(struct mtd_info *master,
+		   struct mtd_partition **pparts,
+		   struct mtd_part_parser_data *data)
+{
+	struct mtd_partition *parts;
+	struct trx_header hdr;
+	int nr_parts;
+	size_t offset;
+	size_t trx_offset;
+	size_t trx_size = 0;
+	size_t rootfs_offset;
+	size_t rootfs_size = 0;
+	int ret;
+
+	nr_parts = 2;
+	parts = kzalloc(nr_parts * sizeof(*parts), GFP_KERNEL);
+	if (!parts)
+		return -ENOMEM;
+
+	/* find trx image on erase block boundaries */
+	for (offset = 0; offset < master->size; offset += master->erasesize) {
+		trx_size = 0;
+
+		ret = read_trx_header(master, offset, &hdr);
+		if (ret)
+			continue;
+
+		if (hdr.magic != cpu_to_le32(TRX_MAGIC)) {
+			pr_debug("no valid trx header found in \"%s\" at offset %llx\n",
+				 master->name, (unsigned long long) offset);
+			continue;
+		}
+
+		trx_size = le32_to_cpu(hdr.len);
+		if ((offset + trx_size) > master->size) {
+			pr_debug("trx image exceeds MTD device \"%s\"\n",
+				 master->name);
+			continue;
+		}
+		break;
+	}
+
+	if (trx_size == 0) {
+		pr_debug("no trx header found in \"%s\"\n", master->name);
+		ret = -ENODEV;
+		goto err;
+	}
+
+	trx_offset = offset + hdr.offset[0];
+	rootfs_offset = offset + hdr.offset[1];
+	rootfs_size = master->size - rootfs_offset;
+	trx_size = rootfs_offset - trx_offset;
+
+	if (rootfs_size == 0) {
+		pr_debug("no rootfs found in \"%s\"\n", master->name);
+		ret = -ENODEV;
+		goto err;
+	}
+
+	parts[0].name = KERNEL_PART_NAME;
+	parts[0].offset = trx_offset;
+	parts[0].size = trx_size;
+
+	parts[1].name = ROOTFS_PART_NAME;
+	parts[1].offset = rootfs_offset;
+	parts[1].size = rootfs_size;
+
+	*pparts = parts;
+	return nr_parts;
+
+err:
+	kfree(parts);
+	return ret;
+}
+
+static struct mtd_part_parser trx_parser = {
+	.owner = THIS_MODULE,
+	.name = "trx-fw",
+	.parse_fn = mtdsplit_parse_trx,
+	.type = MTD_PARSER_TYPE_FIRMWARE,
+};
+
+static int __init mtdsplit_trx_init(void)
+{
+	register_mtd_parser(&trx_parser);
+
+	return 0;
+}
+
+module_init(mtdsplit_trx_init);