[Intel-gfx] [PATCH 3/4] drm/i915: Enabling pre-multiplied alpha drm property

[sagar.a.kamble at intel.com]

From: Sagar Kamble <sagar.a.kamble at intel.com>

This patch enables property for changin the pixel format
of plane to enable/disable pre-multiplied alpha format.
Client has to set BIT(DRM_BLEND_PREMULTIPLIED_ALPHA) | 0x0/0x1
to disable/enable pre-multiplied alpha format.

Cc: Daniel Vetter <daniel.vetter at ffwll.ch>
Cc: Jani Nikula <jani.nikula at linux.intel.com>
Cc: David Airlie <airlied at linux.ie>
Signed-off-by: Srinivas, Vidya <vidya.srinivas at intel.com>
Signed-off-by: Sagar Kamble <sagar.a.kamble at intel.com>
---
 drivers/gpu/drm/i915/intel_drv.h    |  1 +
 drivers/gpu/drm/i915/intel_sprite.c | 73 ++++++++++++++++++++++++++++++++++++-
 2 files changed, 73 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/i915/intel_drv.h b/drivers/gpu/drm/i915/intel_drv.h
index e33124c..44c366d 100644
--- a/drivers/gpu/drm/i915/intel_drv.h
+++ b/drivers/gpu/drm/i915/intel_drv.h
@@ -685,6 +685,7 @@ int intel_get_pipe_from_crtc_id(struct drm_device *dev, void *data,
 enum transcoder intel_pipe_to_cpu_transcoder(struct drm_i915_private *dev_priv,
 					     enum pipe pipe);
 void intel_wait_for_vblank(struct drm_device *dev, int pipe);
+u32 control_premultiplied_alpha(u32 pixformat, unsigned int alpha);
 void intel_wait_for_pipe_off(struct drm_device *dev, int pipe);
 int ironlake_get_lanes_required(int target_clock, int link_bw, int bpp);
 void vlv_wait_port_ready(struct drm_i915_private *dev_priv,
diff --git a/drivers/gpu/drm/i915/intel_sprite.c b/drivers/gpu/drm/i915/intel_sprite.c
index 4c3d2a2..183bd80 100644
--- a/drivers/gpu/drm/i915/intel_sprite.c
+++ b/drivers/gpu/drm/i915/intel_sprite.c
@@ -120,6 +120,10 @@ vlv_update_plane(struct drm_plane *dplane, struct drm_crtc *crtc,
 		I915_WRITE(sprconstalpha, (blend_factor & SPRITE_CONSTANT_ALPHA_MASK) |
 						SPRITE_CONSTANT_ALPHA_ENABLE);
 		break;
+	case DRM_BLEND_PREMULTIPLIED_ALPHA:
+		sprctl |= control_premultiplied_alpha(sprctl & SP_PIXFORMAT_MASK,
+						blend_factor);
+		break;
 	default:
 		DRM_DEBUG_DRIVER("%x Blending operation not supported", intel_plane->blend_param.details.type);
 		break;
@@ -249,6 +253,7 @@ ivb_update_plane(struct drm_plane *plane, struct drm_crtc *crtc,
 	struct intel_plane *intel_plane = to_intel_plane(plane);
 	int pipe = intel_plane->pipe;
 	u32 sprctl, sprscale = 0;
+	unsigned int blend_type, blend_factor;
 	unsigned long sprsurf_offset, linear_offset;
 	int pixel_size = drm_format_plane_cpp(fb->pixel_format, 0);
 
@@ -283,6 +288,22 @@ ivb_update_plane(struct drm_plane *plane, struct drm_crtc *crtc,
 		BUG();
 	}
 
+	/* Handle plane alpha and color blending properties */
+	blend_type = intel_plane->blend_param.details.type;
+	blend_factor = intel_plane->blend_param.details.factor;
+
+	switch (blend_type) {
+	case DRM_BLEND_NONE:
+		break;
+	case DRM_BLEND_PREMULTIPLIED_ALPHA:
+		sprctl |= control_premultiplied_alpha(sprctl & SPRITE_PIXFORMAT_MASK,
+						blend_factor);
+		break;
+	default:
+		DRM_DEBUG_DRIVER("%x Blending operation not supported", intel_plane->blend_param.details.type);
+		break;
+	}
+
 	/*
 	 * Enable gamma to match primary/cursor plane behaviour.
 	 * FIXME should be user controllable via propertiesa.
@@ -434,6 +455,7 @@ ilk_update_plane(struct drm_plane *plane, struct drm_crtc *crtc,
 	int pipe = intel_plane->pipe;
 	unsigned long dvssurf_offset, linear_offset;
 	u32 dvscntr, dvsscale;
+	unsigned int blend_type, blend_factor;
 	int pixel_size = drm_format_plane_cpp(fb->pixel_format, 0);
 
 	dvscntr = I915_READ(DVSCNTR(pipe));
@@ -467,6 +489,22 @@ ilk_update_plane(struct drm_plane *plane, struct drm_crtc *crtc,
 		BUG();
 	}
 
+	/* Handle plane alpha and color blending properties */
+	blend_type = intel_plane->blend_param.details.type;
+	blend_factor = intel_plane->blend_param.details.factor;
+
+	switch (blend_type) {
+	case DRM_BLEND_NONE:
+		break;
+	case DRM_BLEND_PREMULTIPLIED_ALPHA:
+		dvscntr |= control_premultiplied_alpha(dvscntr & DVS_PIXFORMAT_MASK,
+					blend_factor);
+		break;
+	default:
+		DRM_DEBUG_DRIVER("%x Blending operation not supported", intel_plane->blend_param.details.type);
+		break;
+	}
+
 	/*
 	 * Enable gamma to match primary/cursor plane behaviour.
 	 * FIXME should be user controllable via propertiesa.
@@ -1112,6 +1150,38 @@ static uint32_t vlv_plane_formats[] = {
 	DRM_FORMAT_VYUY,
 };
 
+u32 control_premultiplied_alpha(u32 pixformat, unsigned int alpha)
+{
+	switch (pixformat) {
+	case DISPPLANE_RGBX888:
+	case DISPPLANE_RGBA888:
+		if (alpha)
+			pixformat = DISPPLANE_RGBA888;
+		else
+			pixformat = DISPPLANE_RGBX888;
+		break;
+	case DISPPLANE_BGRX888:
+	case DISPPLANE_BGRA888:
+		if (alpha)
+			pixformat = DISPPLANE_BGRA888;
+		else
+			pixformat = DISPPLANE_BGRX888;
+		break;
+	case DISPPLANE_RGBX101010:
+	case DISPPLANE_RGBA101010:
+		if (alpha)
+			pixformat = DISPPLANE_RGBA101010;
+		else
+			pixformat = DISPPLANE_RGBX101010;
+		break;
+	default:
+		if (alpha)
+			DRM_DEBUG_DRIVER("Pixel format 0x%08x does not support Alpha Control\n", pixformat);
+		break;
+	}
+	return pixformat;
+}
+
 int
 intel_plane_init(struct drm_device *dev, enum pipe pipe, int plane)
 {
@@ -1201,7 +1271,8 @@ intel_plane_init(struct drm_device *dev, enum pipe pipe, int plane)
 	if (!dev_priv->blend_property)
 		dev_priv->blend_property = drm_mode_create_blend_property(dev,
 							BIT(DRM_BLEND_NONE) |
-							BIT(DRM_BLEND_CONSTANT_ALPHA));
+							BIT(DRM_BLEND_CONSTANT_ALPHA) |
+							BIT(DRM_BLEND_PREMULTIPLIED_ALPHA));
 
 	if (dev_priv->blend_property)
 		drm_object_attach_property(&intel_plane->base.base,
-- 
1.8.5