[Mesa3d-dev] [HD3470/R600] graphics corruption, GPU lockup...

[Alex Deucher]

On Wed, Sep 30, 2009 at 10:20 AM, Daniel J Blueman
<daniel.blueman at gmail.com> wrote:
> When running 2.6.32-rc1 with modesetting on a HD3470/R600 GPU [1] with
> updated userland [2], I experience a GPU lockup 2-3 seconds after
> starting glxgears under compiz. We also see intermittent rendering
> buffer corruption [3] when glxgears is started, and sometimes
> corruption with text compositing in eg gnome-terminal.
>
> When the GPU lockup occurs, we observe Xorg is waiting for the GPU
> operation to complete [4]; DRM debug reflects this [5]. Xorg.log
> [attached] isn't telling.
>
> The problem isn't reproducible booting with 'nomodeset', so sounds
> like the radeon KMS init path doesn't correctly/consistently
> initialise some registers. What tools would be useful to dump the
> state, perhaps so I can perform a like for like comparison?
>

There may be some buffer accounting issues with draw prims under kms.
Does disabling draw prims fix the issue?  To disable the draw prims
interface, revert this patch:
http://cgit.freedesktop.org/mesa/mesa/commit/?id=eea30906de37ea3b2f8a594c2b33b643d3dde987

Alex