Ubuntu
linux package

  1. Bug #1785912
  2. Comment #114

Comment 114 for bug 1785912

Revision history for this message
In , Bugs-i (bugs-i) wrote :

Working (fastset at boot):
[ 3.494890] [drm:intel_dump_pipe_config [i915]] dp m_n: lanes: 4; gmch_m: 6213395, gmch_n: 8388608, link_m: 517782, link_n: 524288, tu: 64

Broken (modeset):
[ 192.531640] [drm:intel_dump_pipe_config [i915]] dp m_n: lanes: 4; gmch_m: 6213395, gmch_n: 8388608, link_m: 1035565, link_n: 1048576, tu: 64

in intel_dp.c:

 bool constant_n = drm_dp_has_quirk(&intel_dp->desc,
        DP_DPCD_QUIRK_CONSTANT_N);

Replace with
 bool constant_n = true;

And rebuild.

Could you test if it works then?