From 22a2c8e0457f5d66db0819a49beb8c119d8f7a97 Mon Sep 17 00:00:00 2001 From: Dhinakaran Pandiyan Date: Tue, 15 Nov 2016 12:59:06 -0800 Subject: [PATCH] drm/i915: Validate mode against max. link data rate for DP MST MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit Not validating the mode rate against max. link rate results in not pruning invalid modes. For e.g, a HBR2 5.4 Gbps 2-lane configuration does not support 4k@60Hz. But, we do not reject this mode. So, make use of the helpers in intel_dp to validate mode data rate against max. link data rate of a configuration. v3: Renamed local variables again for consistency (Manasi) v2: Renamed mode data rate local variable to be more explanatory. Signed-off-by: Dhinakaran Pandiyan Link: http://patchwork.freedesktop.org/patch/msgid/1479243546-17189-1-git-send-email-dhinakaran.pandiyan@intel.com Signed-off-by: Ville Syrjälä --- drivers/gpu/drm/i915/intel_dp.c | 4 ++-- drivers/gpu/drm/i915/intel_dp_mst.c | 12 +++++++++++- drivers/gpu/drm/i915/intel_drv.h | 2 ++ 3 files changed, 15 insertions(+), 3 deletions(-) diff --git a/drivers/gpu/drm/i915/intel_dp.c b/drivers/gpu/drm/i915/intel_dp.c index 53fc1b3f6770..db75bb924e48 100644 --- a/drivers/gpu/drm/i915/intel_dp.c +++ b/drivers/gpu/drm/i915/intel_dp.c @@ -161,14 +161,14 @@ static u8 intel_dp_max_lane_count(struct intel_dp *intel_dp) return min(source_max, sink_max); } -static int +int intel_dp_link_required(int pixel_clock, int bpp) { /* pixel_clock is in kHz, divide bpp by 8 for bit to Byte conversion */ return DIV_ROUND_UP(pixel_clock * bpp, 8); } -static int +int intel_dp_max_data_rate(int max_link_clock, int max_lanes) { /* max_link_clock is the link symbol clock (LS_Clk) in kHz and not the diff --git a/drivers/gpu/drm/i915/intel_dp_mst.c b/drivers/gpu/drm/i915/intel_dp_mst.c index 1f98757f61e7..205fe4748ec5 100644 --- a/drivers/gpu/drm/i915/intel_dp_mst.c +++ b/drivers/gpu/drm/i915/intel_dp_mst.c @@ -350,7 +350,17 @@ static enum drm_mode_status intel_dp_mst_mode_valid(struct drm_connector *connector, struct drm_display_mode *mode) { + struct intel_connector *intel_connector = to_intel_connector(connector); + struct intel_dp *intel_dp = intel_connector->mst_port; int max_dotclk = to_i915(connector->dev)->max_dotclk_freq; + int bpp = 24; /* MST uses fixed bpp */ + int max_rate, mode_rate, max_lanes, max_link_clock; + + max_link_clock = intel_dp_max_link_rate(intel_dp); + max_lanes = drm_dp_max_lane_count(intel_dp->dpcd); + + max_rate = intel_dp_max_data_rate(max_link_clock, max_lanes); + mode_rate = intel_dp_link_required(mode->clock, bpp); /* TODO - validate mode against available PBN for link */ if (mode->clock < 10000) @@ -359,7 +369,7 @@ intel_dp_mst_mode_valid(struct drm_connector *connector, if (mode->flags & DRM_MODE_FLAG_DBLCLK) return MODE_H_ILLEGAL; - if (mode->clock > max_dotclk) + if (mode_rate > max_rate || mode->clock > max_dotclk) return MODE_CLOCK_HIGH; return MODE_OK; diff --git a/drivers/gpu/drm/i915/intel_drv.h b/drivers/gpu/drm/i915/intel_drv.h index 1d126c29598f..fd77a3ba857b 100644 --- a/drivers/gpu/drm/i915/intel_drv.h +++ b/drivers/gpu/drm/i915/intel_drv.h @@ -1457,6 +1457,8 @@ bool intel_dp_read_dpcd(struct intel_dp *intel_dp); bool __intel_dp_read_desc(struct intel_dp *intel_dp, struct intel_dp_desc *desc); bool intel_dp_read_desc(struct intel_dp *intel_dp); +int intel_dp_link_required(int pixel_clock, int bpp); +int intel_dp_max_data_rate(int max_link_clock, int max_lanes); /* intel_dp_aux_backlight.c */ int intel_dp_aux_init_backlight_funcs(struct intel_connector *intel_connector); -- 2.11.0