The patch below does not apply to the 4.9-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to <stable@xxxxxxxxxxxxxxx>. thanks, greg k-h ------------------ original commit in Linus's tree ------------------ >From 2c57b18adb93fc070039538f1ce375d3d3e99bbb Mon Sep 17 00:00:00 2001 From: Daniel Vetter <daniel.vetter@xxxxxxxx> Date: Tue, 13 Dec 2016 20:54:14 +0100 Subject: [PATCH] drm/i915: tune down the fast link training vs boot fail MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit It's been unfixed since a while and no one is immediately working on this. And we have the FIXME already. And now also a task in the DP team's backlog. Cc: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx> Cc: stable@xxxxxxxxxxxxxxx Cc: Ville Syrjälä <ville.syrjala@xxxxxxxxxxxxxxx> References: https://lists.freedesktop.org/archives/intel-gfx/2016-July/101951.html Acked-by: Ville Syrjälä <ville.syrjala@xxxxxxxxxxxxxxx> [danvet: Adjust comment per Ville's feedback.] Signed-off-by: Daniel Vetter <daniel.vetter@xxxxxxxxx> Link: http://patchwork.freedesktop.org/patch/msgid/20161213195414.28923-1-daniel.vetter@xxxxxxxx (cherry picked from commit 2dd85aeb5bc99e3763dd192cdb95ff405a102c8a) Signed-off-by: Jani Nikula <jani.nikula@xxxxxxxxx> diff --git a/drivers/gpu/drm/i915/intel_dp.c b/drivers/gpu/drm/i915/intel_dp.c index 90283edcafba..d9bc19be855e 100644 --- a/drivers/gpu/drm/i915/intel_dp.c +++ b/drivers/gpu/drm/i915/intel_dp.c @@ -4014,8 +4014,8 @@ intel_dp_check_link_status(struct intel_dp *intel_dp) return; /* FIXME: we need to synchronize this sort of stuff with hardware - * readout */ - if (WARN_ON_ONCE(!intel_dp->lane_count)) + * readout. Currently fast link training doesn't work on boot-up. */ + if (!intel_dp->lane_count) return; /* if link training is requested we should perform it always */ -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html