It is possible the we request to have a mode that has higher pixel clock than our HW can support. This patch checks if requested pixel clock is lower than the one supported by the HW. The requested mode is discarded if we cannot support the requested pixel clock. This patch applies to DisplayPort. Signed-off-by: Mika Kahola <mika.kahola@xxxxxxxxx> --- drivers/gpu/drm/i915/intel_dp.c | 25 ++++++++++++++++++++++++- 1 file changed, 24 insertions(+), 1 deletion(-) diff --git a/drivers/gpu/drm/i915/intel_dp.c b/drivers/gpu/drm/i915/intel_dp.c index fcc64e5..2e55dff 100644 --- a/drivers/gpu/drm/i915/intel_dp.c +++ b/drivers/gpu/drm/i915/intel_dp.c @@ -197,6 +197,26 @@ intel_dp_max_data_rate(int max_link_clock, int max_lanes) return (max_link_clock * max_lanes * 8) / 10; } +static int +intel_dp_max_pixclk(struct intel_dp *intel_dp) +{ + struct intel_digital_port *intel_dig_port = dp_to_dig_port(intel_dp); + struct intel_encoder *encoder = &intel_dig_port->base; + struct drm_device *dev = encoder->base.dev; + struct drm_crtc *crtc = intel_dig_port->base.base.crtc; + struct drm_i915_private *dev_priv = to_i915(dev); + struct intel_crtc *intel_crtc = to_intel_crtc(crtc); + + if (IS_CHERRYVIEW(dev)) + return DIV_ROUND_UP(dev_priv->max_cdclk_freq * 100, 95); + else if (IS_VALLEYVIEW(dev)) + return DIV_ROUND_UP(dev_priv->max_cdclk_freq * 100, 90); + else if (IS_BROADWELL(dev) && intel_crtc->config->ips_enabled) + return DIV_ROUND_UP(dev_priv->max_cdclk_freq * 100, 95); + else + return dev_priv->max_cdclk_freq; +} + static enum drm_mode_status intel_dp_mode_valid(struct drm_connector *connector, struct drm_display_mode *mode) @@ -206,6 +226,7 @@ intel_dp_mode_valid(struct drm_connector *connector, struct drm_display_mode *fixed_mode = intel_connector->panel.fixed_mode; int target_clock = mode->clock; int max_rate, mode_rate, max_lanes, max_link_clock; + int max_pixclk; if (is_edp(intel_dp) && fixed_mode) { if (mode->hdisplay > fixed_mode->hdisplay) @@ -223,7 +244,9 @@ intel_dp_mode_valid(struct drm_connector *connector, max_rate = intel_dp_max_data_rate(max_link_clock, max_lanes); mode_rate = intel_dp_link_required(target_clock, 18); - if (mode_rate > max_rate) + max_pixclk = intel_dp_max_pixclk(intel_dp); + + if ((mode_rate > max_rate) || (target_clock > max_pixclk)) return MODE_CLOCK_HIGH; if (mode->clock < 10000) -- 1.9.1 _______________________________________________ Intel-gfx mailing list Intel-gfx@xxxxxxxxxxxxxxxxxxxxx http://lists.freedesktop.org/mailman/listinfo/intel-gfx