[U-Boot] Raspberry Pi GPIO interacts with u-boot

[Reza Nikoopour]

Hey guys,

I'm working on setting up an NTP server using the following:

Raspberry Pi Model B+
>
Raspberry PI GPS Add-on <
> http://imall.iteadstudio.com/raspberry-pi-gps-add-on.html >
> FreeBSD 10.1 (built with Crochet) <
> https://github.com/kientzle/crochet-freebsd >
>
u-boot-pi < https://github.com/gonzoua/u-boot-pi >
>

I've run into a problem with u-boot.  If I boot the Pi without anything
plugged into the GPIO port it boots all the way into FreeBSD.  However,
when I try to boot with the GPS Add-on plugged into the GPIO, it does not
boot past u-boot.

When the GPS Add-on is plugged while booting the autoboot prompt shows
saying "Press any key to abort autoboot" (or something to that effect)
then the letter 'L' appears on the screen and starts moving from right to
left erasing text it comes across then moving up to the next line.  When it
reaches the top line the 'L' moves from the right side of the screen to the
left and then wraps back around to the right indefinitely.

My rpi_b.h config file can be found at <
https://gist.github.com/rnikoopour/c4cfc271b4856816ee99 >.

I thought this was an issue of the GPS Add-on input being read by the
serial console as valid input.  I tried disabling the serial console by
removing the UART console lines and adding < #define CONFIG_8xx_CONS_NONE
>.  I also tried disabling the GPIO port by commenting out the GPIO section
as well.

Would anyone know why this is happening or how I can fix this?

Thanks,
Reza