[U-Boot] Support for reading GPIO's in boot scripts?

[Mike Frysinger]

On Mon, Mar 28, 2011 at 4:57 AM, Rogan Dawes wrote:
> I'm wondering if there is any support in u-boot for reading the state of
> a GPIO input (i.e. button) to control the sequence of boot events?
>
> i.e. my board has a reset button, can I read its state to determine
> whether to try to TFTP-boot a new kernel, or to boot the existing one in
> flash?
>
> I did try to grep the sources for any hints, but did not find anything.
> I may have been looking in the wrong place, of course!

i plan on generalizing arch/blackfin/cpu/cmd_gpio.c for all arches in
this next cycle (it is mostly done).  but that would require your arch
to support the generic gpio layer.
-mike