Among the work that Marek committed today after floating around on the Mesa development list for a while were an EXPCLEAR optimization, a change to R600g/RadeonSI HTILE initialization, fast depth clear for RadeonSI, a HyperZ performance improvement, a fix for HyperZ hanging on R600g/RadeonSI, a golden setting for R700 GPUs, fixing layered clear, improved fast depth clears for R600g, R600g using the HTILE allocator from RadeonSI, and several other changes.
These changes to AMD's R600g and RadeonSI Gallium3D drivers should improve the stability and performance of HyperZ, a performance-focused feature with a troubled history inside the open-source driver stack. Hopefully after these latest improvements have been more widely tested, AMD will be able to enable the feature again by default. These patches are found in mainline Git for Mesa 10.4-devel. The HyperZ support can be manually enabled by setting the R600_DEBUG=hyperz until it gets turned back on. HyperZ is an easy way to boost the open-source Radeon Linux GPU driver performance.