Hey, Op 03-09-15 om 14:11 schreef Ville Syrjälä: > On Thu, Aug 27, 2015 at 06:36:48PM +0300, ville.syrj...@linux.intel.com wrote: >> From: Ville Syrjälä <ville.syrj...@linux.intel.com> >> >> Grab the connection_mutex around MSR link retraining to protect it >> against a concurrent modeset. We already do the same for SST. >> >> DP hpd_pulse can still otherwise race against modeset and ->detect(), so >> it's not clear what will happen when both want to scribble into eg. >> intel_dp->dpcd[] at the same time. But sorting it all out requires way >> more thought than I'm willing to expend now. > Actually I suppose this might not work out so well after all. I suppose > MST depends on short HPDs during modeset due to the sideband stuff. > > So if we want to grab modeset locks for retraining, I suppose we'd > need to move the retraining to happen from .hot_plug() which gets run > from the other hotplug work, and so wouldn't interfere with sideband. > I think it would be better to have a per encoder mutex. In the future we may want to run modeset disable/enable async, in which case it may not hold the connection_mutex.
If we do decide on a separate mutex then it would also be useful to also think about how to protect intel_mst_*(dis,en)able_dp. :) ~Maarten _______________________________________________ Intel-gfx mailing list Intel-gfx@lists.freedesktop.org http://lists.freedesktop.org/mailman/listinfo/intel-gfx
