There's UVD support all the way back to R600 (the first AMD chipset to include UVD), two generations before Northern Islands (which I think is what Brazos has),

There's UVD support all the way back to R600 (the first AMD chipset to include UVD), two generations before Northern Islands (which I think is what Brazos has), and there has been since before fglrx was discontinued AFAICT. I think on most distributions this support is packaged separately from the rest of Mesa, which may be why you didn't see it.