[U-Boot] u-boot for Snow problem

[Simon Glass]

Hi Michal,

On 11 February 2015 at 10:16, Michal Suchanek <hramrach at gmail.com> wrote:
>
> Hello,
>
> I changed the SYS_START to work around the bug in the manufacturer
> firmware, applied snow_defconfig, built u-boot.bin, packed it into
> kernel uimage, signed it, copied it to a kernel partition, bumped
> priority of the partition, and rebooted.
>

Do you mean u-boot-dtb.bin? If not you won't get a device tree and it
won't work.

> I get black screen with backlight on.
>
> So
>
> 1) is u-boot supposed to have graphics console output?
> If so where is that output? LCD/HDMI/what HDMI mode?
>
> The only display related option in menuconfig seems to be some SPI
> display bridge.

Yes it should be enabled, works for me.

>
> 2) is u-boot supposed to have serial console output?
> If so where is that console?
> There is supposed to be some 'servo' connector somewhere but I did not
> find any information on the pinout.

Yes but you can only access it on the servo pints. From Pit/Pi this is
a little easier, but for snow you will need to do some very fine
soldering.

>
> 3) how do I tell if u-boot is even running?

I think you are doing the right things.

Regards,
Simon