[GK104] MST DisplayPort HiDPI screen flicker

Submitted by JM9

Assigned to Nouveau Project

Link to original bug (#108520)

Description

HiDPI MST monitor connected via DisplayPort has bad screen flicker (one to three high speed flickers every 20 seconds or so).

Version of X: 1.20
Nouveau: 1.0.15-3
Kernel: 4.18.16-arch1-1-ARCH

Curiously, the flicker only happens on my Optimus laptop with Hybrid Graphics disabled (Intel off, Nouveau on). The flicker disappears if Hybrid Graphics is enabled (Both Intel and Nouveau cards on).

Can't find anything relevant in dmesg, journal etc., but let me know which logs will be useful and I can upload them.