[U-Boot-Users] Modifying U-Boot

Hi, when modifying u-boot for a custom design board, is schematic of the board is required? i have datasheet of the board that explain memory map, bridge and cpu type, ex. is this datasheet sufficient to modify u-boot? if schematic is required, what are names of u-boot source files that must be modifyed according to schematic?

Best regards, Mustafa