--- /dev/null
+/*
+ * MTD split for Broadcom Whole Flash Image
+ *
+ * Copyright (C) 2020 Álvaro Fernández Rojas <noltari@gmail.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.
+ *
+ */
+
+#define je16_to_cpu(x) ((x).v16)
+#define je32_to_cpu(x) ((x).v32)
+
+#include <linux/crc32.h>
+#include <linux/init.h>
+#include <linux/jffs2.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/slab.h>
+#include <linux/byteorder/generic.h>
+#include <linux/mtd/mtd.h>
+#include <linux/mtd/partitions.h>
+
+#include "mtdsplit.h"
+
+#define BCM_WFI_PARTS 4
+
+#define CFERAM_NAME "cferam"
+#define CFERAM_NAME_LEN (sizeof(CFERAM_NAME) - 1)
+#define KERNEL_NAME "vmlinux.lz"
+#define KERNEL_NAME_LEN (sizeof(KERNEL_NAME) - 1)
+#define OPENWRT_NAME "1-openwrt"
+#define OPENWRT_NAME_LEN (sizeof(OPENWRT_NAME) - 1)
+
+#define UBI_MAGIC 0x55424923
+
+static u32 jffs2_dirent_crc(struct jffs2_raw_dirent *node)
+{
+ return crc32(0, node, sizeof(struct jffs2_raw_dirent) - 8);
+}
+
+static bool jffs2_dirent_valid(struct jffs2_raw_dirent *node)
+{
+ return ((je16_to_cpu(node->magic) == JFFS2_MAGIC_BITMASK) &&
+ (je16_to_cpu(node->nodetype) == JFFS2_NODETYPE_DIRENT) &&
+ je32_to_cpu(node->ino) &&
+ je32_to_cpu(node->node_crc) == jffs2_dirent_crc(node));
+}
+
+static int jffs2_find_file(struct mtd_info *master, uint8_t *buf,
+ const char *name, size_t name_len,
+ loff_t *offs)
+{
+ struct jffs2_raw_dirent *node;
+ bool valid = false;
+ size_t retlen;
+ uint16_t magic;
+ int rc;
+
+ for (; *offs < master->size; *offs += master->erasesize) {
+ unsigned int block_offs = 0;
+
+ /* Skip CFE erased blocks */
+ rc = mtd_read(master, *offs, sizeof(magic), &retlen,
+ (void *) &magic);
+ if (rc || retlen != sizeof(magic)) {
+ continue;
+ }
+
+ /* Skip blocks not starting with JFFS2 magic */
+ if (magic != JFFS2_MAGIC_BITMASK)
+ continue;
+
+ /* Read full block */
+ rc = mtd_read(master, *offs, master->erasesize, &retlen,
+ (void *) buf);
+ if (rc)
+ return rc;
+ if (retlen != master->erasesize)
+ return -EINVAL;
+
+ while (block_offs < master->erasesize) {
+ node = (struct jffs2_raw_dirent *) &buf[block_offs];
+
+ if (!jffs2_dirent_valid(node)) {
+ block_offs += 4;
+ continue;
+ }
+
+ if (!memcmp(node->name, OPENWRT_NAME,
+ OPENWRT_NAME_LEN))
+ valid = true;
+ else if (!memcmp(node->name, name, name_len))
+ return valid ? 0 : -EINVAL;
+
+ block_offs += je32_to_cpu(node->totlen);
+ block_offs = (block_offs + 0x3) & ~0x3;
+ }
+ }
+
+ return -ENOENT;
+}
+
+static int ubifs_find(struct mtd_info *master, loff_t *offs)
+{
+ uint32_t magic;
+ size_t retlen;
+ int rc;
+
+ for (; *offs < master->size; *offs += master->erasesize) {
+ rc = mtd_read(master, *offs, sizeof(magic), &retlen,
+ (unsigned char *) &magic);
+ if (rc || retlen != sizeof(magic))
+ continue;
+
+ if (be32_to_cpu(magic) == UBI_MAGIC)
+ return 0;
+ }
+
+ return -ENOENT;
+}
+
+static int mtdsplit_parse_bcm_wfi(struct mtd_info *master,
+ const struct mtd_partition **pparts,
+ struct mtd_part_parser_data *data)
+{
+ struct mtd_partition *parts;
+ loff_t cfe_off, kernel_off, rootfs_off;
+ uint8_t *buf;
+ int ret;
+
+ buf = kzalloc(master->erasesize, GFP_KERNEL);
+ if (!buf)
+ return -ENOMEM;
+
+ cfe_off = 0;
+ ret = jffs2_find_file(master, buf, CFERAM_NAME, CFERAM_NAME_LEN,
+ &cfe_off);
+ if (ret) {
+ kfree(buf);
+ return ret;
+ }
+
+ kernel_off = cfe_off + master->erasesize;
+ ret = jffs2_find_file(master, buf, KERNEL_NAME, KERNEL_NAME_LEN,
+ &kernel_off);
+ kfree(buf);
+ if (ret)
+ return ret;
+
+ rootfs_off = kernel_off + master->erasesize;
+ ret = ubifs_find(master, &rootfs_off);
+ if (ret)
+ return ret;
+
+ parts = kzalloc(BCM_WFI_PARTS * sizeof(*parts), GFP_KERNEL);
+ if (!parts)
+ return -ENOMEM;
+
+ parts[0].name = "cferam";
+ parts[0].mask_flags = MTD_WRITEABLE;
+ parts[0].offset = 0;
+ parts[0].size = kernel_off;
+
+ parts[1].name = "firmware";
+ parts[1].offset = kernel_off;
+ parts[1].size = master->size - kernel_off;
+
+ parts[2].name = KERNEL_PART_NAME;
+ parts[2].offset = kernel_off;
+ parts[2].size = rootfs_off - kernel_off;
+
+ parts[3].name = UBI_PART_NAME;
+ parts[3].offset = rootfs_off;
+ parts[3].size = master->size - rootfs_off;
+
+ *pparts = parts;
+
+ return BCM_WFI_PARTS;
+}
+
+static const struct of_device_id mtdsplit_fit_of_match_table[] = {
+ { .compatible = "brcm,wfi" },
+ { },
+};
+
+static struct mtd_part_parser mtdsplit_bcm_wfi_parser = {
+ .owner = THIS_MODULE,
+ .name = "bcm-wfi-fw",
+ .of_match_table = mtdsplit_fit_of_match_table,
+ .parse_fn = mtdsplit_parse_bcm_wfi,
+ .type = MTD_PARSER_TYPE_FIRMWARE,
+};
+
+static int __init mtdsplit_bcm_wfi_init(void)
+{
+ register_mtd_parser(&mtdsplit_bcm_wfi_parser);
+
+ return 0;
+}
+
+module_init(mtdsplit_bcm_wfi_init);
projects / openwrt / staging / dedeckeh.git / commitdiff