https://bugs.winehq.org/show_bug.cgi?id=31644
--- Comment #14 from Stanisław Halik sthalik@misaki.pl --- FWIW, the issue is moot with the Radeon binary driver. Mesa is now of sufficiently high quality, not to mention gallium-nine.
Originally I was able to make a rejected patch with AMD-specific buffer pinning extensions, but it was reported that it caused artifacts in Morrowind at least.
In any case I recommend avoiding the AMD binary driver.