[U-Boot] env_mmc: support overriding mmc dev from board code

[Peng Fan <van.freenix@gmail.com>]

On Mon, Jan 25, 2016 at 09:13:00PM -0500, Tom Rini wrote:
>On Tue, Jan 26, 2016 at 09:42:38AM +0800, Peng Fan wrote:
>> On Mon, Jan 25, 2016 at 04:28:55PM -0500, Tom Rini wrote:
>> >On Wed, Jan 20, 2016 at 03:43:37PM +0100, Clemens Gruber wrote:
>> >
>> >> This enables boards to choose where to/from the environment should be
>> >> saved/loaded. They can then for example support using the same device
>> >> (dynamically) from which the bootloader was launched to load and save
>> >> env data and do not have to define CONFIG_SYS_MMC_ENV_DEV statically.
>> >> 
>> >> In my use case, the environment needs to be on the same device I
>> >> booted from. It can be the eMMC or an optional SD card.
>> >> I therefore would override mmc_get_env_dev in the board code, read the
>> >> CPU registers to determine where we booted from and return the
>> >> corresponding device index.
>> >> 
>> >> Cc: Tom Rini <trini@konsulko.com>
>> >> Cc: Stephen Warren <swarren@nvidia.com>
>> >> Cc: Tim Harvey <tharvey@gateworks.com>
>> >> Cc: Simon Glass <sjg@chromium.org>
>> >> Cc: Hans de Goede <hdegoede@redhat.com>
>> >> 
>> >> Signed-off-by: Clemens Gruber <clemens.gruber@pqgruber.com>
>> >> Reviewed-by: Stephen Warren <swarren@nvidia.com>
>> >> Reviewed-by: Tom Rini <trini@konsulko.com>
>> >
>> >Applied to u-boot/master, thanks!
>> 
>> Oh. I missed this patch. I have a more complete patch, still in patch work.
>> https://patchwork.ozlabs.org/patch/558056/.
>
>Bah.  They look to cover the same areas to me at least.

Yeah. The patch I wrote include fix write_env, and a function prototype in
header file.

If the current patch already applied, I can write a follow up patch.

Thanks,
Peng.

>
>-- 
>Tom