How write graphics driver from scratch?

Hello to all gooroos of programming :slight_smile:
I need driver for RadeonHD series, but some ppl want very money for build it. So i decided to try develop this driver myself.
Well, i had read documentation about graphics DDK on help, found some source code for linux drivers, but i see, i need more information about video driver development. So please tell me, where i can get useful information, how write driver from srcatch,step by step.
thank u )

Isn’t Radeon that company that won’t divulge any hardware details?