[PATCH] MTD: bcm63xxpart: handle Broadcom partition order

[Florian Fainelli]

On Thursday 19 April 2012 13:15:57 Jonas Gorski wrote:
> The original Broadcom partition order has the root fs in front of the
> kernel, which resulted in miscalculated partition sizes.
> Detect when such an image is on the flash and also reorder the partitions
> accordingly.
> 
> Signed-off-by: Jonas Gorski <jonas.gorski at gmail.com>

Acked-by: Florian Fainelli <florian at openwrt.org>

> ---
> 
> This patch is made on top of l2-mtd.
> 
>  drivers/mtd/bcm63xxpart.c |   41 ++++++++++++++++++++++++++++++-----------
>  1 files changed, 30 insertions(+), 11 deletions(-)
> 
> diff --git a/drivers/mtd/bcm63xxpart.c b/drivers/mtd/bcm63xxpart.c
> index 608321e..63d2a64 100644
> --- a/drivers/mtd/bcm63xxpart.c
> +++ b/drivers/mtd/bcm63xxpart.c
> @@ -4,7 +4,7 @@
>   * Copyright © 2006-2008  Florian Fainelli <florian at openwrt.org>
>   *			  Mike Albon <malbon at openwrt.org>
>   * Copyright © 2009-2010  Daniel Dickinson <openwrt at cshore.neomailbox.net>
> - * Copyright © 2011 Jonas Gorski <jonas.gorski at gmail.com>
> + * Copyright © 2011-2012  Jonas Gorski <jonas.gorski at 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
> @@ -82,6 +82,7 @@ static int bcm63xx_parse_cfe_partitions(struct mtd_info
> *master, int namelen = 0;
>  	int i;
>  	u32 computed_crc;
> +	bool rootfs_first = false;
> 
>  	if (bcm63xx_detect_cfe(master))
>  		return -EINVAL;
> @@ -109,6 +110,7 @@ static int bcm63xx_parse_cfe_partitions(struct mtd_info
> *master, 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);
> @@ -117,10 +119,19 @@ static int bcm63xx_parse_cfe_partitions(struct
> mtd_info *master, tagversion, boardid);
> 
>  		kerneladdr = kerneladdr - BCM63XX_EXTENDED_SIZE;
> -		rootfsaddr = kerneladdr + kernellen;
> +		rootfsaddr = rootfsaddr - BCM63XX_EXTENDED_SIZE;
>  		spareaddr = roundup(totallen, master->erasesize) + cfelen;
>  		sparelen = master->size - spareaddr - nvramlen;
> -		rootfslen = spareaddr - rootfsaddr;
> +
> +		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);
> @@ -156,18 +167,26 @@ static int bcm63xx_parse_cfe_partitions(struct
> mtd_info *master, curpart++;
> 
>  	if (kernellen > 0) {
> -		parts[curpart].name = "kernel";
> -		parts[curpart].offset = kerneladdr;
> -		parts[curpart].size = kernellen;
> +		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) {
> -		parts[curpart].name = "rootfs";
> -		parts[curpart].offset = rootfsaddr;
> -		parts[curpart].size = rootfslen;
> -		if (sparelen > 0)
> -			parts[curpart].size += sparelen;
> +		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++;
>  	}
-- 
Florian