Bootloader for S5D9 board

Hello everyone, I wanna ask if there is an exemple of a simple bootloader for s5d9 ssp 1.5.2 and based on threadX. if There is an exemple which is not based on threadx I wanna know the difference between either based on the RTOS or not. I am a newbee to all thos issues thank you guys for answering I would be grateful!