Hi all,
We've recently pushed a couple of new things into main-line U-Boot: native support for displays and support for auto-detection of connected displays.
Combined, we hope this will take a lot of the pain out of configuring the SABRE Lite and Nitrogen6X boards when you receive them.
You can read about the code changes in these two blog posts:
http://boundarydevices.com/u-boot-display-support-for-i-mx6
http://boundarydevices.com/auto-configuration-of-displays-for-i-mx6-using-a-u-boot-script/