[U-Boot] [PATCH] am335x_evm: Consolidate eMMC partitions with DFU info

[Tom Rini]

On Wed, Feb 07, 2018 at 08:41:32PM +0200, Sam Protsenko wrote:

> From DFU_ALT_INFO_EMMC (include/environment/ti/dfu.h) we can see that
> rootfs will be flashed to second partition on eMMC. But at the moment we
> have only one partition in $partitions environment variable. Let's add
> "bootloader" partition prior to "rootfs", so that DFU works correctly.
> This also fixes eMMC boot, which looks for rootfs on second partition.
> 
> "bootloader" partition start corresponds to "u-boot.img.raw" in DFU
> eMMC info, which is 0x300 sector (384 KiB offset from eMMC start).
> 
> rootfs start address can be also found from DFU eMMC info.
> bootloader-related area is finished at 0x1500 sector (2688 KiB offset
> from eMMC start). This should be the start address for rootfs in
> $partitions environment variable.
> 
> While at it, fix U-Boot environment address to be the same as for
> AM57x EVM, so that it doesn't clash with other partitions.
> 
> So now eMMC layout looks like this:
> 
>     ===============================================================
> 
>     0       +------------------------+
>             | MBR/GPT header         |   128           -
>     128     +------------------------+
>             | MLO                    |   256           -
>     384     +------------------------+
>             | u-boot.img             |   1792          bootloader
>     2176    +------------------------+
>             | //////// hole //////// |   256           -
>     2432    +------------------------+
>             | U-Boot environment     |   128           -
>     2560    +------------------------+
>             | U-Boot environment     |   128           -
>             | (redundant)            |
>     2688    +------------------------+
>             | rootfs                 |   remaining     rootfs
>     end     +------------------------+
> 
>     ===============================================================
> 
> "hole" area can be used further for storing U-Boot environment (like
> it's done in AM57x EVM config file) or for increasing u-boot.img area
> (in case u-boot.img size increased, e.g. if new dtbs were added).
> 
> This commit conforms with Linux partition table from f6d245b8c56c
> ("arm: am57xx: Fix Linux boot from eMMC") commit, making things in
> uniform way.
> 
> Signed-off-by: Sam Protsenko <semen.protsenko at linaro.org>

Reviewed-by: Tom Rini <trini at konsulko.com>

-- 
Tom