Hi Chris,
As a first step, I would say you need to port a bootloader to your board. U-boot is commonly used.
Take a look at mx28 support in U-boot.
After you have the bootloader running, then you need to add your board into the kernel.
You can use FSL 2.6.35 or if you want a more recent one, then you can use 3.17, which uses device tree and would probably do the porting process a lot easier.