https://bugzilla.kernel.org/show_bug.cgi?id=24462
Summary: r600: spread spectrum: flickering screen (bisected) Product: Drivers Version: 2.5 Kernel Version: 2.6.37-rc5 Platform: All OS/Version: Linux Tree: Mainline Status: NEW Severity: normal Priority: P1 Component: Video(DRI - non Intel) AssignedTo: drivers_video-dri@kernel-bugs.osdl.org ReportedBy: kronos.it@gmail.com Regression: Yes
2.6.37-rc5 exhibits a slight screen (notebook panel) flickering, mostly noticeable around text (e.g. white-on-black in xterm) with occasional horizontal lines; using 2.6.36 as known "good" kernel I've bisected the issue down to this commit:
ba032a58d1f320039e7850fb6e8651695c1aa571 is the first bad commit commit ba032a58d1f320039e7850fb6e8651695c1aa571 Author: Alex Deucher alexdeucher@gmail.com Date: Mon Oct 4 17:13:01 2010 -0400
drm/radeon/kms: rework spread spectrum handling
This patch reworks spread spectrum handling to enable it properly on lvds and DP/eDP links. It also fixes several bugs in the old spread spectrum code.
- Use the ss recommended reference divider if available when calculating the pll - Use the proper ss command tables on pre-DCE3 asics - Avoid reading past the end of the ss info tables - Enable ss on evergreen asics (lvds, dp, tmds) - Enable ss on DP/eDP links
Signed-off-by: Alex Deucher alexdeucher@gmail.com Signed-off-by: Dave Airlie airlied@redhat.com
:040000 040000 2017e6abb9a12586686bcddb61479f2b158c9d7c 7e6117db061ef286ab6822455c65cf5492de7eaa M drivers
Hardware is a M76: 01:00.0 VGA compatible controller: ATI Technologies Inc M76 [Radeon Mobility HD 2600 Series]
dmesg is attached.