Tiling is one of the features well known for being able to boost the 3D performance of graphics drivers. Since Mesa 9.2 there has been tiling support for Southern Islands (HD 7000 series) graphics processors so now AMD is preparing to enable the feature by default rather than hiding it behind a xorg.conf option.
The simple patch to enable Southern Islands tiling by default can be found on the xorg-driver-ati list but will hopefully soon be merged to master. Yesterday I delivered new RadeonSI open-source driver tests showing AMD's RadeonSI Gallium3D Is Improving, But Catalyst Is Much Better. New benchmarks looking at Southern Islands tiling are forthcoming.