Phoronix evaluates the progress AMD made with its open-source Radeon driver in the past four years, you can read it over here.
"While the BFS scheduler is getting ready to celebrate its
second birthday, in just three weeks AMD's open-source Radeon graphics
driver strategy for Linux will be turning four years old. It was on the
6th of September in 2007 that I exclusively broke the news to the world
on AMD's open-source strategy, which has ended up being a game-changer
in the Linux world. AMD continues to support open-source hardware
enablement on their latest graphics processors and recently even hired
more developers to work on the code and documentation. How far have they
come though in four years?"