It has been found out that in some HW combination the DisplayPort
fast link training feature caused screen flickering. Let's revert
this feature for now until we can ensure that the feature works for
all platforms.
This is a manual revert of commits 5fa836a9d8 ("drm/i915: DP link
training optimization") and 4e96c97742 ("drm/i915: eDP link training
optimization").
Fixes: 5fa836a9d8 ("drm/i915: DP link training optimization")
Fixes: 4e96c97742 ("drm/i915: eDP link training optimization")
Cc: <stable@vger.kernel.org> # v4.2+
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=91393
Reviewed-by: Jani Nikula <jani.nikula@intel.com>
Signed-off-by: Mika Kahola <mika.kahola@intel.com>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1466410226-19543-1-git-send-email-mika.kahola@intel.com
Per spec, TPS3 support is mandatory for downstream devices that support
HBR2. We've therefore logged errors on HBR2 without TPS3 since
commit 1da7d7131c
Author: Jani Nikula <jani.nikula@intel.com>
Date: Thu Sep 3 11:16:08 2015 +0300
drm/i915: ignore link rate in TPS3 selection
However, it seems there are real world devices out there that just
aren't spec compliant, and still work at HBR2 using TPS2. So reduce the
error message to debug logging.
Cc: Ander Conselvan de Oliveira <conselvan2@gmail.com>
Cc: Sivakumar Thulasimani <sivakumar.thulasimani@intel.com>
Reviewed-by: Sivakumar Thulasimani <sivakumar.thulasimani@intel.com>
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=92932
Fixes: 1da7d7131c ("drm/i915: ignore link rate in TPS3 selection")
Cc: drm-intel-fixes@lists.freedesktop.org
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1454667370-8001-2-git-send-email-jani.nikula@intel.com
In order to prepare for a link training with DDI, the state machine
would call intel_ddi_prepare_link_retrain(). To remove the dependency to
the hardware information, replace that direct call with a callback.
Signed-off-by: Ander Conselvan de Oliveira <ander.conselvan.de.oliveira@intel.com>
Reviewed-by: Sivakumar Thulasimani <sivakumar.thulasimani@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1445594525-7174-7-git-send-email-ander.conselvan.de.oliveira@intel.com
Mika Kahola