We've bisected an issue with kernels since commit bb0f4aab0e7677e91cde443fecc18e71fbb85038 Author: Ville Syrjälä <ville.syrjala@linux.intel.com> Date: Fri Jan 20 20:21:59 2017 +0200 drm/i915: Track full cdclk state for the logical and actual cdclk frequencies Attaching a 4k monitor via a TB dock to a certain KBL machine results in display corruption similar to this: https://photos.google.com/share/AF1QipNgcr1DzxLQE40mUrNj_vbZUz_hfcsrsRONqHt-t01tjWsDDQzPfcigCN0BC5lkpg?key=YjRfZk03cFBDeUtYakRFdFVaRGdGLUQzcHhxNjZB
I can still reduplicate this issue with the mainline kernel v4.13~rc3.
Changing priority since is a Regression w/o workaround reproducible. Hello Timo, Shih-Yuan, Could you share full dmesg with parameter drm.debug=0x1e log_bug_len=4M (or bigger) on grub from boot till problem, if possible of bad and good commit to compare? Thank you.
Created attachment 133988 [details] dmesg good case
Created attachment 133989 [details] dmesg bad case
I compared the good and bad cases by the mainline kernel v4.13. The bad case has some additional hotplug events. I don't know if it is related. [drm:intel_get_hpd_pins [i915]] hotplug event received, stat 0x01000000, dig 0x11101010, pins 0x00000010 [drm:intel_hpd_irq_handler [i915]] digital hpd port A - short [drm:intel_dp_hpd_pulse [i915]] got hpd irq on port A - short [drm:intel_dp_read_dpcd [i915]] DPCD: 14 00 c4 c1 00 00 01 c0 02 00 00 00 00 0b 00 [drm:i915_hotplug_work_func [i915]] running encoder hotplug functions [drm:i915_hotplug_work_func [i915]] Connector eDP-1 (pin 4) received hotplug event. [drm:intel_dp_detect [i915]] [CONNECTOR:48:eDP-1] [drm:intel_dp_detect [i915]] Display Port TPS3 support: source yes, sink yes [drm:intel_dp_print_rates [i915]] source rates: 162000, 216000, 270000, 324000, 432000, 540000 [drm:intel_dp_print_rates [i915]] sink rates: 162000, 216000, 243000, 270000, 324000, 432000, 540000 [drm:intel_dp_print_rates [i915]] common rates: 162000, 216000, 270000, 324000, 432000, 540000 [drm:drm_dp_read_desc [drm_kms_helper]] DP sink: OUI 38-ec-11 dev-ID HW-rev 0.0 SW-rev 0.0 quirks 0x0000 [drm:intel_get_hpd_pins [i915]] hotplug event received, stat 0x01000000, dig 0x11101010, pins 0x00000010 [drm:intel_hpd_irq_handler [i915]] digital hpd port A - short [drm:intel_dp_hpd_pulse [i915]] got hpd irq on port A - short [drm:intel_dp_read_dpcd [i915]] DPCD: 14 00 c4 c1 00 00 01 c0 02 00 00 00 00 0b 00
Created attachment 134955 [details] dmesg after goto sleep->wake (start flickering)
Created attachment 134956 [details] DMESG before going sleep (from start) - no flickering
I have similar issue ( flickering ) with the same sympthoms - continuous hotplug events after sleep. dmesg attachments added. Kernel version doesn't matter - try on a lot of kernels.
Sorry for the longish delays. Have you tested this with latest kernel or even with drm-tip? Ville mentioned there could be some changes that could help on this.
Hi Timo, any updates?
Hi Jani, I have tested http://kernel.ubuntu.com/~kernel-ppa/mainline/drm-intel-next/2018-03-09/ (cod/tip/drm-intel-next/2018-03-09 (cf07a60f03f06d6298f4e70b3865bd5faac21c3b) ) and it works fine. Could you point out which changes help on this?
I don't know, but it would probably need a reverse bisect to find out what fixed it.
The fix has been included in the mainline kernel 4.14-rc1.
commit 53421c2fe99c ("drm/i915: Apply Display WA #1183 on skl, kbl, and cfl") is the one suspect I have for this. If it's not that one then a reverse bisect would be nice.
Closing, please re-open if still occurs.
Use of freedesktop.org services, including Bugzilla, is subject to our Code of Conduct. How we collect and use information is described in our Privacy Policy.