AMD have actually released a surprising amount of documentation, for instance: http://developer.amd.com/sdks/AMDAPPSDK/assets/AMD_Southern_Islands_Instruction_

AMD have actually released a surprising amount of documentation, for instance: http://developer.amd.com/sdks/AMDAPPSDK/assets/AMD_Southern_Islands_Instruction_Set_Architecture.pdf http://developer.amd.com/sdks/AMDAPPSDK/assets/AMD_Southern_... http://amd-dev.wpengine.netdna-cdn.com/wordpress/media/2013/10/CIK_3D_registers_v2.pdf http://amd-dev.wpengine.netdna-cdn.com/wordpress/media/2013/... http://www.amd.com/Documents/GCN_Architecture_whitepaper.pdf http://www.amd.com/Documents/GCN_Architecture_whitepaper.pdf