mtd: maps: bcm963xx-flash: make CFE partition parsing an mtd parser

Recent BCM63XX devices support a variety of flash types (parallel, SPI,
NAND) and share the partition layout. To prevent code duplication make
the CFE partition parsing code a stand alone mtd parser to allow SPI or
NAND flash drivers to use it.

Signed-off-by: Jonas Gorski <jonas.gorski@gmail.com>
Acked-by: Florian Fainelli <florian@openwrt.org>
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>

1 files changed, 189 insertions, 0 deletions

diff --git a/drivers/mtd/bcm63xxpart.c b/drivers/mtd/bcm63xxpart.c
new file mode 100644
index 0000000..ac7d3c8
--- /dev/null
+++ b/drivers/mtd/bcm63xxpart.c
@@ -0,0 +1,189 @@
+/*
+ * BCM63XX CFE image tag parser
+ *
+ * Copyright © 2006-2008  Florian Fainelli <florian@openwrt.org>
+ *			  Mike Albon <malbon@openwrt.org>
+ * Copyright © 2009-2010  Daniel Dickinson <openwrt@cshore.neomailbox.net>
+ * Copyright © 2011 Jonas Gorski <jonas.gorski@gmail.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
+ *
+ */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/slab.h>
+#include <linux/vmalloc.h>
+#include <linux/mtd/mtd.h>
+#include <linux/mtd/partitions.h>
+
+#include <asm/mach-bcm63xx/bcm963xx_tag.h>
+
+#define BCM63XX_EXTENDED_SIZE	0xBFC00000	/* Extended flash address */
+
+static int bcm63xx_detect_cfe(struct mtd_info *master)
+{
+	int idoffset = 0x4e0;
+	static char idstring[8] = "CFE1CFE1";
+	char buf[9];
+	int ret;
+	size_t retlen;
+
+	ret = master->read(master, idoffset, 8, &retlen, (void *)buf);
+	buf[retlen] = 0;
+	pr_info("Read Signature value of %s\n", buf);
+
+	return strncmp(idstring, buf, 8);
+}
+
+static int bcm63xx_parse_cfe_partitions(struct mtd_info *master,
+					struct mtd_partition **pparts,
+					struct mtd_part_parser_data *data)
+{
+	/* CFE, NVRAM and global Linux are always present */
+	int nrparts = 3, curpart = 0;
+	struct bcm_tag *buf;
+	struct mtd_partition *parts;
+	int ret;
+	size_t retlen;
+	unsigned int rootfsaddr, kerneladdr, spareaddr;
+	unsigned int rootfslen, kernellen, sparelen, totallen;
+	int namelen = 0;
+	int i;
+	char *boardid;
+	char *tagversion;
+
+	if (bcm63xx_detect_cfe(master))
+		return -EINVAL;
+
+	/* Allocate memory for buffer */
+	buf = vmalloc(sizeof(struct bcm_tag));
+	if (!buf)
+		return -ENOMEM;
+
+	/* Get the tag */
+	ret = master->read(master, master->erasesize, sizeof(struct bcm_tag),
+							&retlen, (void *)buf);
+	if (retlen != sizeof(struct bcm_tag)) {
+		vfree(buf);
+		return -EIO;
+	}
+
+	sscanf(buf->kernel_address, "%u", &kerneladdr);
+	sscanf(buf->kernel_length, "%u", &kernellen);
+	sscanf(buf->total_length, "%u", &totallen);
+	tagversion = &(buf->tag_version[0]);
+	boardid = &(buf->board_id[0]);
+
+	pr_info("CFE boot tag found with version %s and board type %s\n",
+		tagversion, boardid);
+
+	kerneladdr = kerneladdr - BCM63XX_EXTENDED_SIZE;
+	rootfsaddr = kerneladdr + kernellen;
+	spareaddr = roundup(totallen, master->erasesize) + master->erasesize;
+	sparelen = master->size - spareaddr - master->erasesize;
+	rootfslen = spareaddr - rootfsaddr;
+
+	/* Determine number of partitions */
+	namelen = 8;
+	if (rootfslen > 0) {
+		nrparts++;
+		namelen += 6;
+	}
+	if (kernellen > 0) {
+		nrparts++;
+		namelen += 6;
+	}
+
+	/* Ask kernel for more memory */
+	parts = kzalloc(sizeof(*parts) * nrparts + 10 * nrparts, GFP_KERNEL);
+	if (!parts) {
+		vfree(buf);
+		return -ENOMEM;
+	}
+
+	/* Start building partition list */
+	parts[curpart].name = "CFE";
+	parts[curpart].offset = 0;
+	parts[curpart].size = master->erasesize;
+	curpart++;
+
+	if (kernellen > 0) {
+		parts[curpart].name = "kernel";
+		parts[curpart].offset = kerneladdr;
+		parts[curpart].size = kernellen;
+		curpart++;
+	}
+
+	if (rootfslen > 0) {
+		parts[curpart].name = "rootfs";
+		parts[curpart].offset = rootfsaddr;
+		parts[curpart].size = rootfslen;
+		if (sparelen > 0)
+			parts[curpart].size += sparelen;
+		curpart++;
+	}
+
+	parts[curpart].name = "nvram";
+	parts[curpart].offset = master->size - master->erasesize;
+	parts[curpart].size = master->erasesize;
+
+	/* Global partition "linux" to make easy firmware upgrade */
+	curpart++;
+	parts[curpart].name = "linux";
+	parts[curpart].offset = parts[0].size;
+	parts[curpart].size = master->size - parts[0].size - parts[3].size;
+
+	for (i = 0; i < nrparts; i++)
+		pr_info("Partition %d is %s offset %lx and length %lx\n", i,
+			parts[i].name, (long unsigned int)(parts[i].offset),
+			(long unsigned int)(parts[i].size));
+
+	pr_info("Spare partition is offset %x and length %x\n",	spareaddr,
+		sparelen);
+
+	*pparts = parts;
+	vfree(buf);
+
+	return nrparts;
+};
+
+static struct mtd_part_parser bcm63xx_cfe_parser = {
+	.owner = THIS_MODULE,
+	.parse_fn = bcm63xx_parse_cfe_partitions,
+	.name = "bcm63xxpart",
+};
+
+static int __init bcm63xx_cfe_parser_init(void)
+{
+	return register_mtd_parser(&bcm63xx_cfe_parser);
+}
+
+static void __exit bcm63xx_cfe_parser_exit(void)
+{
+	deregister_mtd_parser(&bcm63xx_cfe_parser);
+}
+
+module_init(bcm63xx_cfe_parser_init);
+module_exit(bcm63xx_cfe_parser_exit);
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Daniel Dickinson <openwrt@cshore.neomailbox.net>");
+MODULE_AUTHOR("Florian Fainelli <florian@openwrt.org>");
+MODULE_AUTHOR("Mike Albon <malbon@openwrt.org>");
+MODULE_AUTHOR("Jonas Gorski <jonas.gorski@gmail.com");
+MODULE_DESCRIPTION("MTD partitioning for BCM63XX CFE bootloaders");