just recently the tiling patches for r6xx went into git master. I noticed that r600c works fine with these, but r600g breaks with ColorTiling enabled. To get correct visuals out of the gallium driver I have to disable tiling first, then it works again.
Seems like r600g misinterprets the tiling state of the framebuffer. The visuals are similar to the ones you got when patching mesa with the tiling patchset, but forgetting to do the same for the ddx.
Created attachment 38811 [details]
I guess I saw the same with recent kernels. Only with r600g, r600c wasn't affected.
Mesa commit 9b146eae2521d8e5f6d3cbefa4f6f7737666313a (Dave Airlie)
"r600g: fix tiling support for ddx supplied buffers"
fixed it at my place.
FWIW, I bisected to kernel commit:
e7aeeba6a8fb86ac52bcffa0b72942f784f2b37f (Alex Deucher)
"drm/radeon/kms/r6xx+: add query for tile config (v2)"
-- system architecture: amd64
-- Linux distribution: Gentoo
-- GPU: RS780G
-- Model: ATI Radeon HD 3200
-- Display connector: VGA
-- xf86-video-ati: b90cb61ccb0f4f80e0627141f223354a9371d47d
-- xserver: 1.9.0
-- mesa: fd266ec62ca772a8551d2d7922d718d9d84bdf07
-- drm: 7ec9a1effa4f551897f91f3b017723a8adf011d9
-- kernel: bisected to e7aeeba6a8fb86ac52bcffa0b72942f784f2b37f