From 344c5bbcb7a282cc59e2f111c8801106c4fe315c Mon Sep 17 00:00:00 2001 From: Jani Nikula Date: Tue, 9 Sep 2014 11:25:13 +0300 Subject: [PATCH] drm/i915/edp: use lane count and link rate from DPCD for eDP eDP panels are generally designed to support only a single clock and lane configuration. commit 56071a207602a451f0c46d3dcc8379b59ef576e2 Author: Jani Nikula Date: Tue May 6 14:56:52 2014 +0300 drm/i915: use lane count and link rate from VBT as minimums for eDP should have started using the optimal link parameters for eDP panels. Turns out a certain other OS uses DPCD instead of VBT, which means trusting VBT on this may not be so reliable after all. Follow suit. Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=81647 Tested-by: Adam Jirasek Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=79386 Tested-by: Narthana Epa Signed-off-by: Jani Nikula Signed-off-by: Daniel Vetter --- drivers/gpu/drm/i915/intel_dp.c | 26 +++++++++----------------- 1 file changed, 9 insertions(+), 17 deletions(-) diff --git a/drivers/gpu/drm/i915/intel_dp.c b/drivers/gpu/drm/i915/intel_dp.c index ab7cd0a75bd5..72bf533596c8 100644 --- a/drivers/gpu/drm/i915/intel_dp.c +++ b/drivers/gpu/drm/i915/intel_dp.c @@ -1068,23 +1068,15 @@ intel_dp_compute_config(struct intel_encoder *encoder, bpp = dev_priv->vbt.edp_bpp; } - if (IS_BROADWELL(dev)) { - /* Yes, it's an ugly hack. */ - min_lane_count = max_lane_count; - DRM_DEBUG_KMS("forcing lane count to max (%u) on BDW\n", - min_lane_count); - } else if (dev_priv->vbt.edp_lanes) { - min_lane_count = min(dev_priv->vbt.edp_lanes, - max_lane_count); - DRM_DEBUG_KMS("using min %u lanes per VBT\n", - min_lane_count); - } - - if (dev_priv->vbt.edp_rate) { - min_clock = min(dev_priv->vbt.edp_rate >> 3, max_clock); - DRM_DEBUG_KMS("using min %02x link bw per VBT\n", - bws[min_clock]); - } + /* + * Use the maximum clock and number of lanes the eDP panel + * advertizes being capable of. The panels are generally + * designed to support only a single clock and lane + * configuration, and typically these values correspond to the + * native resolution of the panel. + */ + min_lane_count = max_lane_count; + min_clock = max_clock; } for (; bpp >= 6*3; bpp -= 2*3) { -- 2.20.1