[U-Boot] [PATCH 4/6] sunxi: When we've both mmc0 and mmc2, detect from which one we're booting

[Hans de Goede]

Hi,

On 10/06/2014 10:33 AM, Ian Campbell wrote:
> On Sun, 2014-10-05 at 17:10 +0200, Hans de Goede wrote:
>>
>> On 10/04/2014 10:35 AM, Ian Campbell wrote:
>>> On Fri, 2014-10-03 at 17:05 +0200, Hans de Goede wrote:
>>>> sunxi SOCs can boot from both mmc0 and mmc2, detect from which one we're
>>>> booting, and make that one "mmc dev 0" so that a single u-boot binary can
>>>> be used for both the onboard eMMC and for external sdcards.
>>>
>>> Where does the dependency on dev 0 being the boot device come from? Is
>>> it just the env via CONFIG_SYS_MMC_ENV_DEV?
>>
>> No, the main reason why we need dev 0 to be the mmc we're actually booting
>> from is because that is where the SPL will load the tertiary payload
>> (the actual u-boot binary in our case) from, see:
>>
>> common/spl/spl_mmc.c
>>
>> Which has dev 0 hardcoded everywhere.
> 
> I see. Could you paste this bit of reasoning into the commit log please?
> (pretty much s/No, t/T/ on the above would do IMHO)

Done for v2.

Regards,

Hans