[U-Boot] [PATCH v3 27/58] fastboot: sunxi: Update fastboot mmc default device

[Jagan Teki]

On Wed, Aug 22, 2018 at 10:13 PM, Maxime Ripard
<maxime.ripard at bootlin.com> wrote:
> On Tue, Aug 21, 2018 at 10:27:38PM +0530, Jagan Teki wrote:
>> On Mon, Aug 20, 2018 at 5:14 PM, Maxime Ripard
>> <maxime.ripard at bootlin.com> wrote:
>> > On Sun, Aug 19, 2018 at 07:26:44PM +0530, Jagan Teki wrote:
>> >> Usually eMMC is default mmc device for fastboot.
>> >>
>> >> By enabling DM_MMC, the mmc devices are probed as per
>> >> DT status not with respect to MMC_SUNXI_SLOT_EXTRA in
>> >> U-Boot proper.
>> >>
>> >> Allwinner SoC has maximum of 4 mmc controllers start from
>> >> mmc0...mmc3 on which mmc2 can be used an eMMC controller
>> >> eventhough mmc3 some boards used as eMMC.
>> >>
>> >> So, update the default fastboot device as 2 to make the
>> >> standard usage irrespective of DT node status.
>> >>
>> >> Other corner cases like different device usage, or specific
>> >> mmc node status is not enabled in order in DTS must explicitly
>> >> add config on the specific defconfig file.
>> >>
>> >> Cc: Olliver Schinagl <oliver at schinagl.nl>
>> >> Cc: Chen-Yu Tsai <wens at csie.org>
>> >> Signed-off-by: Jagan Teki <jagan at amarulasolutions.com>
>> >
>> > This breaks all existing users, since if DM_MMC isn't set (and it
>> > isn't at the moment), the MMC IDs won't change, and you're changing it
>> > from either 0 or 1 to 2.
>>
>> True, bisectable issue. will take care on next version.
>>
>> >
>> > Can't we have a DT property instead? It looks much better than having
>> > to deal with a non stable ID in Kconfig.
>>
>> What do you mean by DT property handle? mmc2 is eMMC in all sunXi
>> isn't? ie reason I make it default.
>
> I meant to select the fastboot and environment devices. That way, each
> board can select the one it wants in a truly deterministic way.

ie what get_env_fat_dev_part is doing. Identify the dev no.of
initialized mmc or emmc. are you referring something like this?