kernel: mtdsplit: add support for WRGG images

[openwrt/openwrt.git] / target / linux / generic / files / drivers / mtd / mtdsplit / mtdsplit_wrgg.c

diff --git a/target/linux/generic/files/drivers/mtd/mtdsplit/mtdsplit_wrgg.c b/target/linux/generic/files/drivers/mtd/mtdsplit/mtdsplit_wrgg.c
new file mode 100644 (file)
index 0000000..c1fbccb
--- /dev/null
+++ b/target/linux/generic/files/drivers/mtd/mtdsplit/mtdsplit_wrgg.c
@@ -0,0 +1,109 @@
+/*
+ *  Copyright (C) 2013 Gabor Juhos <juhosg@openwrt.org>
+ *  Copyright (C) 2014 Felix Fietkau <nbd@nbd.name>
+ *  Copyright (C) 2016 Stijn Tintel <stijn@linux-ipv6.be>
+ *
+ *  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 WRGG_NR_PARTS          2
+#define WRGG_MIN_ROOTFS_OFFS   0x80000 /* 512KiB */
+#define WRGG03_MAGIC           0x20080321
+
+struct wrgg03_header {
+       char            signature[32];
+       uint32_t        magic1;
+       uint32_t        magic2;
+       char            version[16];
+       char            model[16];
+       uint32_t        flag[2];
+       uint32_t        reserve[2];
+       char            buildno[16];
+       uint32_t        size;
+       uint32_t        offset;
+       char            devname[32];
+       char            digest[16];
+} __attribute__ ((packed));
+
+
+static int mtdsplit_parse_wrgg(struct mtd_info *master,
+                               struct mtd_partition **pparts,
+                               struct mtd_part_parser_data *data)
+{
+       struct wrgg03_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 (le32_to_cpu(hdr.magic1) != WRGG03_MAGIC)
+               return -EINVAL;
+
+       kernel_ent_size = hdr_len + be32_to_cpu(hdr.size);
+
+       if (kernel_ent_size > master->size)
+               return -EINVAL;
+
+       /*
+        * The size in the header covers the rootfs as well.
+        * Start the search from an arbitrary offset.
+        */
+       err = mtd_find_rootfs_from(master, WRGG_MIN_ROOTFS_OFFS,
+                                  master->size, &rootfs_offset, &type);
+       if (err)
+               return err;
+
+       parts = kzalloc(WRGG_NR_PARTS * sizeof(*parts), GFP_KERNEL);
+       if (!parts)
+               return -ENOMEM;
+
+       parts[0].name = KERNEL_PART_NAME;
+       parts[0].offset = 0;
+       parts[0].size = rootfs_offset;
+
+       parts[1].name = ROOTFS_PART_NAME;
+       parts[1].offset = rootfs_offset;
+       parts[1].size = master->size - rootfs_offset;
+
+       *pparts = parts;
+       return WRGG_NR_PARTS;
+}
+
+static struct mtd_part_parser mtdsplit_wrgg_parser = {
+       .owner = THIS_MODULE,
+       .name = "wrgg-fw",
+       .parse_fn = mtdsplit_parse_wrgg,
+       .type = MTD_PARSER_TYPE_FIRMWARE,
+};
+
+static int __init mtdsplit_wrgg_init(void)
+{
+       register_mtd_parser(&mtdsplit_wrgg_parser);
+
+       return 0;
+}
+
+subsys_initcall(mtdsplit_wrgg_init);