ATSAM4S SD card bootloader

Hi I am using ATSAM4S8C cpu [login to view URL] I need a bootloader that can bootload firmware from SD card without being connected to PC. So you load new firmware file on SD card (or external flash chip, but this might be more difficult to implement)insert the SD card in PCB and when the CPU starts up it will see there is a new file and do bootload. I will not provide a dev board (developer MUST be familiar with ATSAM4S and have his own dev tools already), no money will be paid upfront, full payment on completion(money will be placed in escrow at freelancer before development commences).