This goes back to
commit
06ea66b6bb445043dc25a9626254d5c130093199
Author: Todd Previte <tprevite@gmail.com>
Date: Mon Jan 20 10:19:39 2014 -0700
drm/i915: Enable 5.4Ghz (HBR2) link rate for Displayport 1.2-capable devices
Cc: Todd Previte <tprevite@gmail.com>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
[danvet: Pimp commit message a bit.]
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>