On 4 August 2014 18:10, Daniel Vetter <daniel@xxxxxxxx> wrote: > On Fri, Aug 01, 2014 at 02:55:22PM +0300, Ville Syrjälä wrote: >> On Thu, Jul 31, 2014 at 08:59:08PM +1000, Dave Airlie wrote: >> > On 31 July 2014 17:37, Daniel Vetter <daniel@xxxxxxxx> wrote: >> > > On Thu, Jul 31, 2014 at 1:49 AM, Dave Airlie <airlied@xxxxxxxxx> wrote: >> > >> Daniel, the only way intel_dp->is_mst can get reset is inside this path. >> > > >> > > Ok, so that one should be safe. Then I guess we can just push the >> > > locking down into the respective non-mst leafs (since atm we do >> > > link-retraining without any locking, which isn't good). And it needs >> > > to be dev->mode_config.mutex, not connection mutex. >> >> Why that? We can't be doing a modeset w/o connection_mutex so that >> seems like it should be enough. Well, there's also dpms which leaves >> the crtc<->encoder<->connector links intact but that too takes >> connection_mutex currently. >> >> > >> > I'd like to know why we do link training at this point though as well, >> > adding locking is required of course, I was just going to wrap the >> > short irq call to the link status check with the lock, but I think it >> > should be possible to push it down further, >> >> I don't really know why the sink generates the hpd when we turn off the >> port, but that doesn't really matter I think. We need to be prepared for >> hpds at any time. >> >> intel_dp_check_link_status() just checks if there's a crtc, which there >> is (either the old one or the new one, depending on how far along the >> modeset path we are I guess), and then it just checks >> drm_dp_channel_eq_ok() which says false since the link was turned off, >> and then it proceeds to retrain the link. >> >> Maybe it should also check crtc->active? Though that itself won't >> eliminate the problem unless the locking gets fixed somehow. > > We check encoder->connectors_active, which is equivalent. > -Daniel We still check that. if you mean intel_encoders->connectors_active. Dave. _______________________________________________ Intel-gfx mailing list Intel-gfx@xxxxxxxxxxxxxxxxxxxxx http://lists.freedesktop.org/mailman/listinfo/intel-gfx
