Initial commit

target/linux/generic/files/drivers/mtd/mtdsplit/mtdsplit_fit.c

@@ -0,0 +1,141 @@
+/*
+ * Copyright (c) 2015 The Linux Foundation
+ * Copyright (C) 2014 Gabor Juhos <juhosg@openwrt.org>
+ *
+ * Permission to use, copy, modify, and/or distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+ * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+ * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ */
+
+#include <linux/module.h>
+#include <linux/mtd/mtd.h>
+#include <linux/mtd/partitions.h>
+#include <linux/types.h>
+#include <linux/byteorder/generic.h>
+#include <linux/slab.h>
+#include <linux/of_fdt.h>
+
+#include "mtdsplit.h"
+
+struct fdt_header {
+	uint32_t magic;			 /* magic word FDT_MAGIC */
+	uint32_t totalsize;		 /* total size of DT block */
+	uint32_t off_dt_struct;		 /* offset to structure */
+	uint32_t off_dt_strings;	 /* offset to strings */
+	uint32_t off_mem_rsvmap;	 /* offset to memory reserve map */
+	uint32_t version;		 /* format version */
+	uint32_t last_comp_version;	 /* last compatible version */
+
+	/* version 2 fields below */
+	uint32_t boot_cpuid_phys;	 /* Which physical CPU id we're
+					    booting on */
+	/* version 3 fields below */
+	uint32_t size_dt_strings;	 /* size of the strings block */
+
+	/* version 17 fields below */
+	uint32_t size_dt_struct;	 /* size of the structure block */
+};
+
+static int
+mtdsplit_fit_parse(struct mtd_info *mtd,
+		   const struct mtd_partition **pparts,
+	           struct mtd_part_parser_data *data)
+{
+	struct fdt_header hdr;
+	size_t hdr_len, retlen;
+	size_t offset;
+	size_t fit_offset, fit_size;
+	size_t rootfs_offset, rootfs_size;
+	struct mtd_partition *parts;
+	int ret;
+
+	hdr_len = sizeof(struct fdt_header);
+
+	/* Parse the MTD device & search for the FIT image location */
+	for(offset = 0; offset < mtd->size; offset += mtd->erasesize) {
+		ret = mtd_read(mtd, 0, hdr_len, &retlen, (void*) &hdr);
+		if (ret) {
+			pr_err("read error in \"%s\" at offset 0x%llx\n",
+			       mtd->name, (unsigned long long) offset);
+			return ret;
+		}
+
+		if (retlen != hdr_len) {
+			pr_err("short read in \"%s\"\n", mtd->name);
+			return -EIO;
+		}
+
+		/* Check the magic - see if this is a FIT image */
+		if (be32_to_cpu(hdr.magic) != OF_DT_HEADER) {
+			pr_debug("no valid FIT image found in \"%s\" at offset %llx\n",
+				 mtd->name, (unsigned long long) offset);
+			continue;
+		}
+
+		/* We found a FIT image. Let's keep going */
+		break;
+	}
+
+	fit_offset = offset;
+	fit_size = be32_to_cpu(hdr.totalsize);
+
+	if (fit_size == 0) {
+		pr_err("FIT image in \"%s\" at offset %llx has null size\n",
+		       mtd->name, (unsigned long long) fit_offset);
+		return -ENODEV;
+	}
+
+	/* Search for the rootfs partition after the FIT image */
+	ret = mtd_find_rootfs_from(mtd, fit_offset + fit_size, mtd->size,
+				   &rootfs_offset, NULL);
+	if (ret) {
+		pr_info("no rootfs found after FIT image in \"%s\"\n",
+			mtd->name);
+		return ret;
+	}
+
+	rootfs_size = mtd->size - rootfs_offset;
+
+	parts = kzalloc(2 * sizeof(*parts), GFP_KERNEL);
+	if (!parts)
+		return -ENOMEM;
+
+	parts[0].name = KERNEL_PART_NAME;
+	parts[0].offset = fit_offset;
+	parts[0].size = mtd_rounddown_to_eb(fit_size, mtd) + mtd->erasesize;
+
+	parts[1].name = ROOTFS_PART_NAME;
+	parts[1].offset = rootfs_offset;
+	parts[1].size = rootfs_size;
+
+	*pparts = parts;
+	return 2;
+}
+
+static struct mtd_part_parser uimage_parser = {
+	.owner = THIS_MODULE,
+	.name = "fit-fw",
+	.parse_fn = mtdsplit_fit_parse,
+	.type = MTD_PARSER_TYPE_FIRMWARE,
+};
+
+/**************************************************
+ * Init
+ **************************************************/
+
+static int __init mtdsplit_fit_init(void)
+{
+	register_mtd_parser(&uimage_parser);
+
+	return 0;
+}
+
+module_init(mtdsplit_fit_init);