The patch below does not apply to the 5.0-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 5aae7832d1b4ec614996ea0f4fafc4d9855ec0b0 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Ville=20Syrj=C3=A4l=C3=A4?= <ville.syrjala@xxxxxxxxxxxxxxx>
Date: Tue, 26 Mar 2019 16:49:02 +0200
Subject: [PATCH] drm/i915: Do not enable FEC without DSC
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
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Currently we enable FEC even when DSC is no used. While that is
theoretically valid supposedly there isn't much of a benefit from
this. But more importantly we do not account for the FEC link
bandwidth overhead (2.4%) in the non-DSC link bandwidth computations.
So the code may think we have enough bandwidth when we in fact
do not.
Cc: stable@xxxxxxxxxxxxxxx
Cc: Anusha Srivatsa <anusha.srivatsa@xxxxxxxxx>
Cc: Manasi Navare <manasi.d.navare@xxxxxxxxx>
Fixes: 240999cf339f ("i915/dp/fec: Add fec_enable to the crtc state.")
Signed-off-by: Ville Syrjälä <ville.syrjala@xxxxxxxxxxxxxxx>
Link: https://patchwork.freedesktop.org/patch/msgid/20190326144903.6617-1-ville.syrjala@xxxxxxxxxxxxxxx
Reviewed-by: Manasi Navare <manasi.d.navare@xxxxxxxxx>
(cherry picked from commit 6fd3134ae3551d4802a04669c0f39f2f5c56f77d)
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@xxxxxxxxx>
diff --git a/drivers/gpu/drm/i915/intel_dp.c b/drivers/gpu/drm/i915/intel_dp.c
index 8891f29a8c7f..48da4a969a0a 100644
--- a/drivers/gpu/drm/i915/intel_dp.c
+++ b/drivers/gpu/drm/i915/intel_dp.c
@@ -1886,6 +1886,9 @@ static int intel_dp_dsc_compute_config(struct intel_dp *intel_dp,
int pipe_bpp;
int ret;
+ pipe_config->fec_enable = !intel_dp_is_edp(intel_dp) &&
+ intel_dp_supports_fec(intel_dp, pipe_config);
+
if (!intel_dp_supports_dsc(intel_dp, pipe_config))
return -EINVAL;
@@ -2116,9 +2119,6 @@ intel_dp_compute_config(struct intel_encoder *encoder,
if (adjusted_mode->flags & DRM_MODE_FLAG_DBLCLK)
return -EINVAL;
- pipe_config->fec_enable = !intel_dp_is_edp(intel_dp) &&
- intel_dp_supports_fec(intel_dp, pipe_config);
-
ret = intel_dp_compute_link_config(encoder, pipe_config, conn_state);
if (ret < 0)
return ret;
