mtd: add Broadcom BCM63xx image tag partition parser

This patch adds support for parsing Broadcom BCM63xx image tag format and
creating MTD partitions accordingly. This driver is a platform_device which
can be instantiated accordingly by bcm63xx board support code.

Signed-off-by: Daniel Dickinson <cshore@csolve.net>
Signed-off-by: Mike Albon <malbon@openwrt.org>
Signed-off-by: Florian Fainelli <florian@openwrt.org>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>

1 files changed, 271 insertions, 0 deletions

diff --git a/drivers/mtd/maps/bcm963xx-flash.c b/drivers/mtd/maps/bcm963xx-flash.c
new file mode 100644
index 000000000000..d175c120ee84
--- /dev/null
+++ b/drivers/mtd/maps/bcm963xx-flash.c
@@ -0,0 +1,271 @@
+/*
+ * Copyright © 2006-2008  Florian Fainelli <florian@openwrt.org>
+ *			  Mike Albon <malbon@openwrt.org>
+ * Copyright © 2009-2010  Daniel Dickinson <openwrt@cshore.neomailbox.net>
+ *
+ * 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
+ */
+
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/slab.h>
+#include <linux/mtd/map.h>
+#include <linux/mtd/mtd.h>
+#include <linux/mtd/partitions.h>
+#include <linux/vmalloc.h>
+#include <linux/platform_device.h>
+#include <linux/io.h>
+
+#include <asm/mach-bcm63xx/bcm963xx_tag.h>
+
+#define BCM63XX_BUSWIDTH	2		/* Buswidth */
+#define BCM63XX_EXTENDED_SIZE	0xBFC00000	/* Extended flash address */
+
+#define PFX KBUILD_MODNAME ": "
+
+static struct mtd_partition *parsed_parts;
+
+static struct mtd_info *bcm963xx_mtd_info;
+
+static struct map_info bcm963xx_map = {
+	.name		= "bcm963xx",
+	.bankwidth	= BCM63XX_BUSWIDTH,
+};
+
+static int parse_cfe_partitions(struct mtd_info *master,
+						struct mtd_partition **pparts)
+{
+	/* 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;
+
+	/* 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]);
+
+	printk(KERN_INFO PFX "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++)
+		printk(KERN_INFO PFX "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));
+
+	printk(KERN_INFO PFX "Spare partition is %x offset and length %x\n",
+							spareaddr, sparelen);
+	*pparts = parts;
+	vfree(buf);
+
+	return nrparts;
+};
+
+static int bcm963xx_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;
+	printk(KERN_INFO PFX "Read Signature value of %s\n", buf);
+
+	return strncmp(idstring, buf, 8);
+}
+
+static int bcm963xx_probe(struct platform_device *pdev)
+{
+	int err = 0;
+	int parsed_nr_parts = 0;
+	char *part_type;
+	struct resource *r;
+
+	r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	if (!r) {
+		dev_err(&pdev->dev, "no resource supplied\n");
+		return -ENODEV;
+	}
+
+	bcm963xx_map.phys = r->start;
+	bcm963xx_map.size = resource_size(r);
+	bcm963xx_map.virt = ioremap(r->start, resource_size(r));
+	if (!bcm963xx_map.virt) {
+		dev_err(&pdev->dev, "failed to ioremap\n");
+		return -EIO;
+	}
+
+	dev_info(&pdev->dev, "0x%08lx at 0x%08x\n",
+					bcm963xx_map.size, bcm963xx_map.phys);
+
+	simple_map_init(&bcm963xx_map);
+
+	bcm963xx_mtd_info = do_map_probe("cfi_probe", &bcm963xx_map);
+	if (!bcm963xx_mtd_info) {
+		dev_err(&pdev->dev, "failed to probe using CFI\n");
+		err = -EIO;
+		goto err_probe;
+	}
+
+	bcm963xx_mtd_info->owner = THIS_MODULE;
+
+	/* This is mutually exclusive */
+	if (bcm963xx_detect_cfe(bcm963xx_mtd_info) == 0) {
+		dev_info(&pdev->dev, "CFE bootloader detected\n");
+		if (parsed_nr_parts == 0) {
+			int ret = parse_cfe_partitions(bcm963xx_mtd_info,
+							&parsed_parts);
+			if (ret > 0) {
+				part_type = "CFE";
+				parsed_nr_parts = ret;
+			}
+		}
+	} else {
+		dev_info(&pdev->dev, "unsupported bootloader\n");
+		err = -ENODEV;
+		goto err_probe;
+	}
+
+	return add_mtd_partitions(bcm963xx_mtd_info, parsed_parts,
+						parsed_nr_parts);
+
+err_probe:
+	iounmap(bcm963xx_map.virt);
+	return err;
+}
+
+static int bcm963xx_remove(struct platform_device *pdev)
+{
+	if (bcm963xx_mtd_info) {
+		del_mtd_partitions(bcm963xx_mtd_info);
+		map_destroy(bcm963xx_mtd_info);
+	}
+
+	if (bcm963xx_map.virt) {
+		iounmap(bcm963xx_map.virt);
+		bcm963xx_map.virt = 0;
+	}
+
+	return 0;
+}
+
+static struct platform_driver bcm63xx_mtd_dev = {
+	.probe	= bcm963xx_probe,
+	.remove = bcm963xx_remove,
+	.driver = {
+		.name	= "bcm963xx-flash",
+		.owner	= THIS_MODULE,
+	},
+};
+
+static int __init bcm963xx_mtd_init(void)
+{
+	return platform_driver_register(&bcm63xx_mtd_dev);
+}
+
+static void __exit bcm963xx_mtd_exit(void)
+{
+	platform_driver_unregister(&bcm63xx_mtd_dev);
+}
+
+module_init(bcm963xx_mtd_init);
+module_exit(bcm963xx_mtd_exit);
+
+MODULE_LICENSE("GPL");
+MODULE_DESCRIPTION("Broadcom BCM63xx MTD driver for CFE and RedBoot");
+MODULE_AUTHOR("Daniel Dickinson <openwrt@cshore.neomailbox.net>");
+MODULE_AUTHOR("Florian Fainelli <florian@openwrt.org>");
+MODULE_AUTHOR("Mike Albon <malbon@openwrt.org>");