AMD HSA - huma with extra dedicated GPU?

Hi,

i got an AMD A10-7850K and wanted to test and play with

GitHub - HSAFoundation/CLOC: CL Offline Compiler : Compile OpenCL kernels to HSAIL

But i also thought about getting a dedicated GPU to improve

the potential performance. Like an RX480 or RX460. Is this

possible? I mean, does the IOMMUv2 enable the dedicated

GPU to use the system memory as real shared memory, like

the integrated GPU in the APU?

PS: I was not able to find a real document about this IOMMUv2,

maybe i just didn't find it. Also information about how the cache

coherence is realized in the APU between the CPU and GPU

cores is somewhat limited. I only found third party websites with

information on that. Maybe somebody can point me to a good

source.

Thanks!

BR

Simon