Both video and graphics on RK3188 SOC based Mini PCs work great under Android with accelerated hardware processing but for Linux it had to be achieved through software as the hardware drivers are proprietary.
Whilst hardware accelerated video using the VPU is still outstanding, it is now possible to use the GPU for hardware 3D graphics processing in Linux.
If you want to try out "Mali on Linux" on a RK3188 device (such as Radxa Rock, Minix Neo X7, Rikomagic MK802IV etc) then I've prepared an updated Ubuntu 12.04 RFS with the necessary kernel modules and binary userspace drivers. Simply download from here, uncompress and write the image to a SD card or USB (default user is 'linuxium' and initial password is 'p' without the quotes).
On the initial boot it is necessary to delete the Mesa EGL libaries that got re-installed after adding the Mesa utility packages. Remove them by entering 'sudo rm -rf /usr/lib/arm-linux-gnueabihf/mesa-egl'.
Prior to running the 3D graphics demos as a standard user you will need to make sure the permissions are set correctly for a couple of devices. Enter 'sudo chmod 666 /dev/dri/card0' followed by 'sudo chmod 777 /dev/mali'.
You can then try the 3D demos by entering 'es2gears' or 'glmark2-es2'.