Card is an AMD Radeon HD 7950. I’m using kernel 3.15-rc5 + cherrypicks + PTE
patches (VRAM page table entry compression) + hyperz (R600_DEBUG=hyperz). I’m
also using libdrm git, xf86-video-ati git, llvm 3.5 git with a rebased Tom
Stellard’s si-spill-fixes-v4 branch, mesa git (OpenGL core profile version
string: 3.3 (Core Profile) Mesa 10.3.0-devel (git-57730d6)) and Keith Packard’s
xorg-server glamor-server branch (1.16.0 RC 2).

As you can see from the attached screenshot there is graphical corruption:
http://files.linuxsystems.it/files/the_witcher_2_wine_radeonsi.png
It works flawlessly with Catalyst.