/*
* 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 © 2011-2012 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/crc32.h>
#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>
#include <asm/mach-bcm63xx/board_bcm963xx.h>
#define BCM63XX_EXTENDED_SIZE 0xBFC00000 /* Extended flash address */
#define BCM63XX_MIN_CFE_SIZE 0x10000 /* always at least 64KiB */
#define BCM63XX_MIN_NVRAM_SIZE 0x10000 /* always at least 64KiB */
#define BCM63XX_CFE_MAGIC_OFFSET 0x4e0
static int bcm63xx_detect_cfe(struct mtd_info *master)
{
char buf[9];
int ret;
size_t retlen;
ret = mtd_read(master, BCM963XX_CFE_VERSION_OFFSET, 5, &retlen,
(void *)buf);
buf[retlen] = 0;
if (ret)
return ret;
if (strncmp("cfe-v", buf, 5) == 0)
return 0;
/* very old CFE's do not have the cfe-v string, so check for magic */
ret = mtd_read(master, BCM63XX_CFE_MAGIC_OFFSET, 8, &retlen,
(void *)buf);
buf[retlen] = 0;
return strncmp("CFE1CFE1", 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;
unsigned int cfelen, nvramlen;
int namelen = 0;
int i;
u32 computed_crc;
bool rootfs_first = false;
if (bcm63xx_detect_cfe(master))
return -EINVAL;
cfelen = max_t(uint32_t, master->erasesize, BCM63XX_MIN_CFE_SIZE);
nvramlen = max_t(uint32_t, master->erasesize, BCM63XX_MIN_NVRAM_SIZE);
/* Allocate memory for buffer */
buf = vmalloc(sizeof(struct bcm_tag));
if (!buf)
return -ENOMEM;
/* Get the tag */
ret = mtd_read(master, cfelen, sizeof(struct bcm_tag), &retlen,
(void *)buf);
if (retlen != sizeof(struct bcm_tag)) {
vfree(buf);
return -EIO;
}
computed_crc = crc32_le(IMAGETAG_CRC_START, (u8 *)buf,
offsetof(struct bcm_tag, header_crc));
if (computed_crc == buf->header_crc) {
char *boardid = &(buf->board_id[0]);
char *tagversion = &(buf->tag_version[0]);
sscanf(buf->flash_image_start, "%u", &rootfsaddr);
sscanf(buf->kernel_address, "%u", &kerneladdr);
sscanf(buf->kernel_length, "%u", &kernellen);
sscanf(buf->total_length, "%u", &totallen);
pr_info("CFE boot tag found with version %s and board type %s\n",
tagversion, boardid);
kerneladdr = kerneladdr - BCM63XX_EXTENDED_SIZE;
rootfsaddr = rootfsaddr - BCM63XX_EXTENDED_SIZE;
spareaddr = roundup(totallen, master->erasesize) + cfelen;
sparelen = master->size - spareaddr - nvramlen;
if (rootfsaddr < kerneladdr) {
/* default Broadcom layout */
rootfslen = kerneladdr - rootfsaddr;
rootfs_first = true;
} else {
/* OpenWrt layout */
rootfsaddr = kerneladdr + kernellen;
rootfslen = spareaddr - rootfsaddr;
}
} else {
pr_warn("CFE boot tag CRC invalid (expected %08x, actual %08x)\n",
buf->header_crc, computed_crc);
kernellen = 0;
rootfslen = 0;
rootfsaddr = 0;
spareaddr = cfelen;
sparelen = master->size - cfelen - nvramlen;
}
/* 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 = cfelen;
curpart++;
if (kernellen > 0) {
int kernelpart = curpart;
if (rootfslen > 0 && rootfs_first)
kernelpart++;
parts[kernelpart].name = "kernel";
parts[kernelpart].offset = kerneladdr;
parts[kernelpart].size = kernellen;
curpart++;
}
if (rootfslen > 0) {
int rootfspart = curpart;
if (kernellen > 0 && rootfs_first)
rootfspart--;
parts[rootfspart].name = "rootfs";
parts[rootfspart].offset = rootfsaddr;
parts[rootfspart].size = rootfslen;
if (sparelen > 0 && !rootfs_first)
parts[rootfspart].size += sparelen;
curpart++;
}
parts[curpart].name = "nvram";
parts[curpart].offset = master->size - nvramlen;
parts[curpart].size = nvramlen;
/* Global partition "linux" to make easy firmware upgrade */
curpart++;
parts[curpart].name = "linux";
parts[curpart].offset = cfelen;
parts[curpart].size = master->size - cfelen - nvramlen;
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");
