Hi Ville, > "The monitor is connected with a DP+-to-HDMI cable" > This and some reading of the DP dual mode spec gave me another idea; > The DP->HDMI adaptor may simply be degrading the signal quality too > much. According to the DP dual mode spec we're supposed to limit the > TMDS clock based on the type of adapter used, but currently we have > no code to do that. I've cooked up a few patches that should do what > we want: > git://github.com/vsyrjala/linux.git dp_dual_mode > > I've quickly tested it locally, and it seemed to do the right thing > with a few different types of adaptors. I've run 32fa589 for a few hours now and it have not seen a single blank or flicker. So it seems you've nailed it - thanks a lot! Let me know if you want me to test more patches, post debug logs, or anything else. BTW, also discovered right before you sent that e-mail that downgrading to a 1920x1080i mode (rather than the monitor's native 1920x1080) would also stop the flickering. I'd assume that also fits well with your diagnosis (less bandwidth needed => better tolerance for degraded signal quality), but I thought I'd let you know in case not. > > By the way: Is it possible to disable HDMI 12bpc in a way that > > doesn't require me to patch and rebuild the kernel drivers, such as > > a kernel module parameter or sysfs setting? (I prefer to simply use > > the upstream Fedora kernel RPMs, but this issue is currently making > > that impossible.) > > We don't have any knob to control this. I don't need it anymore, so no worries. ;-) Tore _______________________________________________ Intel-gfx mailing list Intel-gfx@xxxxxxxxxxxxxxxxxxxxx https://lists.freedesktop.org/mailman/listinfo/intel-gfx
