Thank you for your contribution! Sashiko AI review found 1 potential issue(s) to consider: - [High] FRL training state is not cleared if the EDID is invalidated before a disconnect, causing subsequent FRL training to be skipped permanently. --
commit 666a7a052848216c6b509f4ba1711921db6e5b40 Author: Xiao Lu <[email protected]> drm/i915/dp: reset HDMI 2.1 PCON FRL state on disconnect When a DP-to-HDMI 2.1 PCON is disconnected, frl.is_trained remains set from the previous connection. On reconnect, intel_dp_check_frl_training() checks this flag first and returns early if set, bypassing the entire FRL training sequence entirely. > diff --git a/drivers/gpu/drm/i915/display/intel_dp.c > b/drivers/gpu/drm/i915/display/intel_dp.c > index 113d767e62e9c..3643b6c4c1bc5 100644 > --- a/drivers/gpu/drm/i915/display/intel_dp.c > +++ b/drivers/gpu/drm/i915/display/intel_dp.c [ ... ] > +/* > + * On disconnect, the downstream PCON and its HDMI FRL link state are gone > + * from the source's perspective. Clear the cached FRL training state so that > + * intel_dp_check_frl_training() performs a fresh FRL negotiation on the next > + * connect, rather than skipping training based on stale state. > + */ > +static void > +intel_dp_pcon_disconnect(struct intel_dp *intel_dp) > +{ > + struct intel_display *display = to_intel_display(intel_dp); > + > + if (!intel_dp_is_hdmi_2_1_sink(intel_dp)) > + return; [Severity: High] Can this early return prevent clearing the FRL state if the EDID is invalidated before a disconnect? If a transient I2C-over-AUX error occurs during a background reprobe while the monitor is still physically connected, it can cause intel_dp_set_edid() to fail. This failure causes drm_edid_connector_update() to be called with NULL, which clears connector->base.display_info and sets is_hdmi to false. If the monitor is subsequently unplugged, triggering a disconnect, this function returns early because intel_dp_is_hdmi_2_1_sink() evaluates to false. The frl.is_trained flag remains true. When the monitor is reconnected, intel_dp_check_frl_training() skips training because is_trained is still true, leading to a permanent blank screen or severely limited resolution until a driver reload or reboot. Should the state clearing be performed unconditionally, since the current sink capabilities can be stale or invalidated? > + > + drm_dbg_kms(display->drm, > + "PCON HDMI2.1 sink disconnected, resetting FRL state (was > trained at %d Gbps)\n", > + intel_dp->frl.trained_rate_gbps); > + intel_dp->frl.is_trained = false; > + intel_dp->frl.trained_rate_gbps = 0; > +} -- Sashiko AI review · https://sashiko.dev/#/patchset/[email protected]?part=1
