This page is still mostly a stub, please add to it!
PowerVR is a line of GPU by Imagination Technologies. It has zero Free Software/Open Source support right now, and the associated development effort seems to be regarded as very high. Imagination has hinted they were considering addressssing the problem but today the position seem to be still open
It is regarded as more powerful than the Mali400 GPU found in other SoCs (needs ref).
Imagination Technologies published a linux driver for their binary microkernel under a dual license: MIT & GPL v2. 
Allwinner SoC with a PowerVR GPU:
|A31||SGX544 or SGX544MP2||1.1.5|
- http://www.cnx-software.com/2015/06/18/open-source-linux-drivers-for-powervr-gpus-might-be-in-the-works/ CNX blog entry
- https://careers.imgtec.com/#/vacancy/details/2619 Open position at Imagination Technologies
- http://www.fsf.org/campaigns/priority.html High Priority Free Software Projects
- http://powervr.gnu.org.ve/doku.php Collecting information about the PowerVR architecture
- https://github.com/LeMaker/linux-actions/tree/linux-3.10.y/drivers/gpu/pvr LeMaker Integrated it into their 3.10.y kernel