On Thu, May 04, 2017 at 05:36:49PM -0300, Gabriel Krisman Bertazi wrote: > On systems where more than one connector is attached to the same port, > the HPD pin is also shared, and attaching one connector will trigger a > hotplug on every other connector on that port. But, according to the > documentation, connectors sharing the port cannot be enabled > simultaneously, such that we can abort the detection process early if > another connector was detected succesfully. > > This has the good side effect of preventing DP timeouts whenever > something else is connected to the shared port, like below: > > [drm:intel_dp_aux_ch [i915]] dp_aux_ch timeout status 0x7143003f > [drm:drm_dp_dpcd_access] Too many retries, giving up. First error: -110 > > Since this reduces the overhead of the i915_hotplug_work_func, it may > address the following vblank misses detected by the CI: > > https://bugs.freedesktop.org/show_bug.cgi?id=100215 > https://bugs.freedesktop.org/show_bug.cgi?id=100558 > > Signed-off-by: Gabriel Krisman Bertazi <krisman@xxxxxxxxxxxxxxx> The key problem here is say a race between DP unplug and HDMI plug, and users are evil enough (or common enough) for it to happen. I thought the idea was reasonable though, and perhaps we could make more use of the knowlege of the shared ports to improve detection of common DP/HDMI DDIs (i.e. run detection once for a ddi and have it decide whether it is hdmi or dp). -Chris -- Chris Wilson, Intel Open Source Technology Centre _______________________________________________ Intel-gfx mailing list Intel-gfx@xxxxxxxxxxxxxxxxxxxxx https://lists.freedesktop.org/mailman/listinfo/intel-gfx
