[drm] *ERROR* failed to enable link training

The symptoms I observe: plugging in/out USB-C to DP cable has zero effect.

The first occurrence of subj error is at Mar 17 11:15:53 nixps kernel: i915 0000:00:02.0: [drm] *ERROR* failed to enable link training (this happened after I unplugged DP cable to charge the battery and once I plugged it back it stopped working)

PS: I'm debugging another drm related issue ([drm] *ERROR* CPU pipe A FIFO underrun) so the log file might be a bit bloated.

kernel.tar.xz

changed the description

Same issue here. Usually after sleep (deep) external display does not work (DP over type-c). I do see FIFO underrun errors as well as "failed to allocate vcpi" stuff.

Same issue here Linux xxxxxxxx 5.14.0-1024-oem #26 (closed)-Ubuntu SMP Thu Feb 17 14:35:50 UTC 2022 x86_64 x86_64 x86_64 GNU/Linux Ubuntu 20.04 HP Elitebook 840 G7

added Community feature: display/DP platform: TGL labels

marked this issue as a duplicate of #62 (closed)

closed

marked this issue as related to #62 (closed)

Over Thunberbolt? I just bought a Cable Matters usb-c / thunderbolt 4 -> DP adapter, which is giving these errors:

[231991.024737] usb usb2-port1: unable to enumerate USB device
[232078.334088] i915 0000:00:02.0: [drm] *ERROR* [CONNECTOR:254:DP-1][ENCODER:253:DDI TC1/PHY TC1][LTTPR 1] Failed to update link training
[232168.201114] i915 0000:00:02.0: drm_WARN_ON(ret)