On Mon, Feb 15, 2016 at 08:17:23PM +0100, Tore Anderson wrote: > Hello, > > Since upgrading to the Fedora 4.3 kernel package, the picture on my the > BenQ M2700 HD monitor I've got connected to my HP EliteBook Folio 9470m > laptop began having issues. The monitor is connected with a DP+-to-HDMI > cable (HDMI in the monitor end), and the resolution I'm using is > 1920x1080. > > The symptoms are brief flickers of which looks like a thin horizontal > line (or maybe more) overlaying the picture for a very brief period. > This is ofte often (but not always) followed by the entire picture > going completely black (kind of like when xscreensaver blanks the > screen). Usually, the picture returns after maybe a second, but > sometimes it remains off for several seconds before returning. It might > also be that these blankings happen without a horizontal line flicker > having occurred immediately before, thought it's hard to be certain > because the flickers are very brief. > > The laptop's internal screen is not impacted, the picture there remains > stable while the external screen is flickering/blanking (including if > both screens are set up in xrandr to show the same output). > > Most of the time the flickers and blankings happens only occasionally, > and be just a minor annoyance. However, some times it gets really bad, > and the screen spends a majority of the time black - making it > impossible to use the system. I have not determined anything that will > with 100% certainty cause the symptoms to manifest themselves, but I do > have a feeling that it is more likely to happen if the picture is > mostly white/bright (e.g., when displaying a web browser window or an > application such as gitk), and also after having resumed from suspend. > But flickering/blanking certainly does happen if the screen showing > mostly black xterms and without having suspended/resumed too. > > I bisected the problem, which resulted in the following verdict: > > 7a0baa6234468aa387f9b8a1a79dc2a4b4821f67 is the first bad commit > commit 7a0baa6234468aa387f9b8a1a79dc2a4b4821f67 > Author: Ville Syrjälä <ville.syrjala@xxxxxxxxxxxxxxx> > Date: Tue Jun 30 15:33:54 2015 +0300 > > Revert "drm/i915: Disable 12bpc hdmi for now" > > HDMI 12bpc should be working fine now. Let it loose. > > This reverts commit 5e3daaca09f5158eff9c92290faa1d2001ecc6e4. > > v2: Rebased due to CHV/BXT port clock check improvemnts > > Signed-off-by: Ville Syrjälä <ville.syrjala@xxxxxxxxxxxxxxx> > Reviewed-and-tested-by: Imre Deak <imre.deak@xxxxxxxxx> > Signed-off-by: Daniel Vetter <daniel.vetter@xxxxxxxx> > > I also confirmed that the problem is still present in drm-intel-nightly > as of today (8ed1804). I'm currently running 8ed1804 + 7a0baa6 reverted > and the symptoms are gone. > > I've uploaded a kernel logs with drm.debug=0xe here: > > http://filebin.net/r3nlwu09y2 > > One file is from when running 8ed1804 (with some comments of when the symptoms > occurred added by me), the other file is from right now (running > 8ed1804 + 7a0baa6 reverted) - I've not yet experienced any issues since > booting the system with this kernel. Could you test the following hack while using a 1920x1080 mode with 148.5 MHz dotclock, and see if there's any improvement? diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c index 4e1321b96522..ea24de873e14 100644 --- a/drivers/gpu/drm/i915/intel_display.c +++ b/drivers/gpu/drm/i915/intel_display.c @@ -12842,6 +12842,11 @@ intel_modeset_pipe_config(struct drm_crtc *crtc, clear_intel_crtc_state(pipe_config); + if (pipe_config->base.adjusted_mode.clock == 148500) { + DRM_ERROR("adjusting dotclock\n"); + pipe_config->base.adjusted_mode.clock = 148800; + } + pipe_config->cpu_transcoder = (enum transcoder) to_intel_crtc(crtc)->pipe; -- Ville Syrjälä Intel OTC _______________________________________________ Intel-gfx mailing list Intel-gfx@xxxxxxxxxxxxxxxxxxxxx https://lists.freedesktop.org/mailman/listinfo/intel-gfx
