drm/i915/hdmi: Enable pipe pixel replication for SD interlaced modes

Enable 2x pixel replication for modes the mode flag DBLCLK to double
horizontal timings and pixel clock across TMDS.

Signed-off-by: Clint Taylor <clinton.a.taylor@intel.com>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>

1 files changed, 12 insertions, 3 deletions

diff --git a/drivers/gpu/drm/i915/intel_hdmi.c b/drivers/gpu/drm/i915/intel_hdmi.c
index 9169786dbbc3..96957683032e 100644
--- a/drivers/gpu/drm/i915/intel_hdmi.c
+++ b/drivers/gpu/drm/i915/intel_hdmi.c
@@ -864,10 +864,15 @@ static enum drm_mode_status
 intel_hdmi_mode_valid(struct drm_connector *connector,
                       struct drm_display_mode *mode)
 {
-        if (mode->clock > hdmi_portclock_limit(intel_attached_hdmi(connector),
-                                               true))
+        int clock = mode->clock;
+
+        if (mode->flags & DRM_MODE_FLAG_DBLCLK)
+                clock *= 2;
+
+        if (clock > hdmi_portclock_limit(intel_attached_hdmi(connector),
+                                         true))
                 return MODE_CLOCK_HIGH;
-        if (mode->clock < 20000)
+        if (clock < 20000)
                 return MODE_CLOCK_LOW;
 
         if (mode->flags & DRM_MODE_FLAG_DBLSCAN)
@@ -921,6 +926,10 @@ bool intel_hdmi_compute_config(struct intel_encoder *encoder,
                         intel_hdmi->color_range = 0;
         }
 
+        if (adjusted_mode->flags & DRM_MODE_FLAG_DBLCLK) {
+                pipe_config->pixel_multiplier = 2;
+        }
+
         if (intel_hdmi->color_range)
                 pipe_config->limited_color_range = true;