4 files changed, 43 insertions, 0 deletions
diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h
index e03a4f80c5c9..83a557c7bcc5 100644
--- a/drivers/gpu/drm/i915/i915_drv.h
+++ b/drivers/gpu/drm/i915/i915_drv.h
@@ -243,6 +243,8 @@ struct drm_i915_display_funcs {
 	void (*update_sprite_wm)(struct drm_device *dev, int pipe,
 				 uint32_t sprite_width, int pixel_size);
 	void (*sanitize_pm)(struct drm_device *dev);
+	void (*update_linetime_wm)(struct drm_device *dev, int pipe,
+				 struct drm_display_mode *mode);
 	int (*crtc_mode_set)(struct drm_crtc *crtc,
 			     struct drm_display_mode *mode,
 			     struct drm_display_mode *adjusted_mode,
diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c
index 39f122b3ce70..fb3f4aaca2c4 100644
--- a/drivers/gpu/drm/i915/intel_display.c
+++ b/drivers/gpu/drm/i915/intel_display.c
@@ -4609,6 +4609,8 @@ static int ironlake_crtc_mode_set(struct drm_crtc *crtc,
 
 	intel_update_watermarks(dev);
 
+	intel_update_linetime_watermarks(dev, pipe, adjusted_mode);
+
 	return ret;
 }
 
diff --git a/drivers/gpu/drm/i915/intel_drv.h b/drivers/gpu/drm/i915/intel_drv.h
index a5bb5b6ebb4f..0ad1bb383976 100644
--- a/drivers/gpu/drm/i915/intel_drv.h
+++ b/drivers/gpu/drm/i915/intel_drv.h
@@ -454,6 +454,8 @@ extern void intel_update_watermarks(struct drm_device *dev);
 extern void intel_update_sprite_watermarks(struct drm_device *dev, int pipe,
 					   uint32_t sprite_width,
 					   int pixel_size);
+extern void intel_update_linetime_watermarks(struct drm_device *dev, int pipe,
+			 struct drm_display_mode *mode);
 
 extern int intel_sprite_set_colorkey(struct drm_device *dev, void *data,
 				     struct drm_file *file_priv);
diff --git a/drivers/gpu/drm/i915/intel_pm.c b/drivers/gpu/drm/i915/intel_pm.c
index 452a9bce8162..8f8d1daf1cac 100644
--- a/drivers/gpu/drm/i915/intel_pm.c
+++ b/drivers/gpu/drm/i915/intel_pm.c
@@ -1883,6 +1883,33 @@ static void sandybridge_update_wm(struct drm_device *dev)
 		   cursor_wm);
 }
 
+static void
+haswell_update_linetime_wm(struct drm_device *dev, int pipe,
+				 struct drm_display_mode *mode)
+{
+	struct drm_i915_private *dev_priv = dev->dev_private;
+	u32 temp;
+
+	temp = I915_READ(PIPE_WM_LINETIME(pipe));
+	temp &= ~PIPE_WM_LINETIME_MASK;
+
+	/* The WM are computed with base on how long it takes to fill a single
+	 * row at the given clock rate, multiplied by 8.
+	 * */
+	temp |= PIPE_WM_LINETIME_TIME(
+		((mode->crtc_hdisplay * 1000) / mode->clock) * 8);
+
+	/* IPS watermarks are only used by pipe A, and are ignored by
+	 * pipes B and C.  They are calculated similarly to the common
+	 * linetime values, except that we are using CD clock frequency
+	 * in MHz instead of pixel rate for the division.
+	 *
+	 * This is a placeholder for the IPS watermark calculation code.
+	 */
+
+	I915_WRITE(PIPE_WM_LINETIME(pipe), temp);
+}
+
 static bool
 sandybridge_compute_sprite_wm(struct drm_device *dev, int plane,
 			      uint32_t sprite_width, int pixel_size,
@@ -2078,6 +2105,15 @@ void intel_update_watermarks(struct drm_device *dev)
 		dev_priv->display.update_wm(dev);
 }
 
+void intel_update_linetime_watermarks(struct drm_device *dev,
+		int pipe, struct drm_display_mode *mode)
+{
+	struct drm_i915_private *dev_priv = dev->dev_private;
+
+	if (dev_priv->display.update_linetime_wm)
+		dev_priv->display.update_linetime_wm(dev, pipe, mode);
+}
+
 void intel_update_sprite_watermarks(struct drm_device *dev, int pipe,
 				    uint32_t sprite_width, int pixel_size)
 {
@@ -3689,6 +3725,7 @@ void intel_init_pm(struct drm_device *dev)
 			if (SNB_READ_WM0_LATENCY()) {
 				dev_priv->display.update_wm = sandybridge_update_wm;
 				dev_priv->display.update_sprite_wm = sandybridge_update_sprite_wm;
+				dev_priv->display.update_linetime_wm = haswell_update_linetime_wm;
 			} else {
 				DRM_DEBUG_KMS("Failed to read display plane latency. "
 					      "Disable CxSR\n");