From fe27d53e5c597ee5ba5d72a29d517091f244e974 Mon Sep 17 00:00:00 2001 From: Dave Airlie Date: Wed, 30 Jun 2010 11:46:17 +1000 Subject: [PATCH] i915: fix ironlake edp panel setup (v4) The eDP spec claims a 20% overhead for the 8:10 encoding scheme used on the wire. Take this into account when picking the lane/clock speed for the panel. v3: some panels are out of spec, try our best to deal with them, don't refuse modes on eDP panels, and try the largest allowed settings if all else fails on eDP. v4: fix stupid typo, forgot to git add before amending. Fixes several reports in bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=28070 Signed-off-by: Dave Airlie Signed-off-by: Eric Anholt --- drivers/gpu/drm/i915/intel_dp.c | 27 ++++++++++++++++++++++++--- 1 file changed, 24 insertions(+), 3 deletions(-) diff --git a/drivers/gpu/drm/i915/intel_dp.c b/drivers/gpu/drm/i915/intel_dp.c index 49b54f05d3cf..1aac59e83bff 100644 --- a/drivers/gpu/drm/i915/intel_dp.c +++ b/drivers/gpu/drm/i915/intel_dp.c @@ -135,6 +135,12 @@ intel_dp_link_required(struct drm_device *dev, return pixel_clock * 3; } +static int +intel_dp_max_data_rate(int max_link_clock, int max_lanes) +{ + return (max_link_clock * max_lanes * 8) / 10; +} + static int intel_dp_mode_valid(struct drm_connector *connector, struct drm_display_mode *mode) @@ -144,8 +150,11 @@ intel_dp_mode_valid(struct drm_connector *connector, int max_link_clock = intel_dp_link_clock(intel_dp_max_link_bw(intel_encoder)); int max_lanes = intel_dp_max_lane_count(intel_encoder); - if (intel_dp_link_required(connector->dev, intel_encoder, mode->clock) - > max_link_clock * max_lanes) + /* only refuse the mode on non eDP since we have seen some wierd eDP panels + which are outside spec tolerances but somehow work by magic */ + if (!IS_eDP(intel_encoder) && + (intel_dp_link_required(connector->dev, intel_encoder, mode->clock) + > intel_dp_max_data_rate(max_link_clock, max_lanes))) return MODE_CLOCK_HIGH; if (mode->clock < 10000) @@ -506,7 +515,7 @@ intel_dp_mode_fixup(struct drm_encoder *encoder, struct drm_display_mode *mode, for (lane_count = 1; lane_count <= max_lane_count; lane_count <<= 1) { for (clock = 0; clock <= max_clock; clock++) { - int link_avail = intel_dp_link_clock(bws[clock]) * lane_count; + int link_avail = intel_dp_max_data_rate(intel_dp_link_clock(bws[clock]), lane_count); if (intel_dp_link_required(encoder->dev, intel_encoder, mode->clock) <= link_avail) { @@ -521,6 +530,18 @@ intel_dp_mode_fixup(struct drm_encoder *encoder, struct drm_display_mode *mode, } } } + + if (IS_eDP(intel_encoder)) { + /* okay we failed just pick the highest */ + dp_priv->lane_count = max_lane_count; + dp_priv->link_bw = bws[max_clock]; + adjusted_mode->clock = intel_dp_link_clock(dp_priv->link_bw); + DRM_DEBUG_KMS("Force picking display port link bw %02x lane " + "count %d clock %d\n", + dp_priv->link_bw, dp_priv->lane_count, + adjusted_mode->clock); + return true; + } return false; } -- 2.20.1