[U-Boot] Can I load uEnv.txt conditionally, based on the boot source?

[Joe Hershberger]

On Tue, Feb 10, 2015 at 7:18 PM, Brian Smucker <bds at bsmucker.eu.org> wrote:
>
> Hello,
>
> I was wondering if there is a way to tell what the boot source is?
>
> My am335x SOC can boot to the mmc or the flash, based on the status of a
digital line. I would like to load the uEnv.txt, only if booting from SD
card (mmc).  I notice at least in some codebases that the automatic loading
of uEnv.txt is based on whether the SD card is available, not whether we
are currently booting from the SD card.
>
> Is there a way to sense which we are booting from?

Are you able to read the same digital line that the SoC is using to decide?