It turns out that AMD's Unified Video Decoding (UVD) support in the open-source Radeon driver has been missing up until now. The missing support hasn't been due to the IP being blocked at AMD or any serious matter like that, but it turns out the Oland chip identifier was missing from a switch statement in the Radeon DRM driver for loading the appropriate firmware and setting the chip ID. Oland uses the same "Tahiti" UVD firmware as for the Radeon HD 7900 series graphics cards from which Oland is derived/re-branded, but the Direct Rendering Manager driver was just missing the two simple lines of code.
For AMD Oland owners missing out on UVD hardware video acceleration the patch can be found on dri-devel and will make it into the Linux 3.14 kernel and quite possibly the back-ported to existing stable kernel series.
This silly oversight in the code comes just weeks after Radeon DRM driver developers also discovered a major RadeonSI performance improvement as a a silly but critical bug where only the render back-ends on the first shader engine of the modern AMD GPUs were being enabled and the rest were ignored. That fix made it into Linux 3.13.