[U-Boot-Users] What is x-loader?

Hi all,

My aim is to port linux to omap2430SDP with pop memory processor board.I want to use U-boot as my bootloader. But i came to know that it requires one more thing called X-loader.

I don't understand why it need X-loader other than U-boot. My board is having pop memory thats why X-loader is needed?

Does anybody here know the answer please help me. It will be a great help to me if somebody is giving me a brief idea about "how to port U-boot to a omap2430 processor with pop memory?".

Thanks in advance arun