[PATCH 6/7] drm/fsl-dcu: fix alpha blending

Stefan Agner
2015-11-19T02:42:30Z

Fix alpha blending by enabling alpha blending for the whole frame if
a color mode with alpha channel is selected (DRM_FORMAT_ARGB*). Also
support color modes without alpha channel (DRM_FORMAT_XRGB*) by just
not enabling alpha blending on layer level.

Signed-off-by: Stefan Agner <stefan@agner.ch>
---
drivers/gpu/drm/fsl-dcu/fsl_dcu_drm_drv.h | 4 +++-
drivers/gpu/drm/fsl-dcu/fsl_dcu_drm_plane.c | 31 +++++++++++++++++++----------
2 files changed, 23 insertions(+), 12 deletions(-)

diff --git a/drivers/gpu/drm/fsl-dcu/fsl_dcu_drm_drv.h b/drivers/gpu/drm/fsl-dcu/fsl_dcu_drm_drv.h
index 579b9e4..6413ac9 100644
--- a/drivers/gpu/drm/fsl-dcu/fsl_dcu_drm_drv.h
+++ b/drivers/gpu/drm/fsl-dcu/fsl_dcu_drm_drv.h
@@ -133,7 +133,9 @@
#define DCU_LAYER_RLE_EN BIT(15)
#define DCU_LAYER_LUOFFS(x) ((x) << 4)
#define DCU_LAYER_BB_ON BIT(2)
-#define DCU_LAYER_AB(x) (x)
+#define DCU_LAYER_AB_NONE 0
+#define DCU_LAYER_AB_CHROMA_KEYING 1
+#define DCU_LAYER_AB_WHOLE_FRAME 2

#define DCU_LAYER_CKMAX_R(x) ((x) << 16)
#define DCU_LAYER_CKMAX_G(x) ((x) << 8)
diff --git a/drivers/gpu/drm/fsl-dcu/fsl_dcu_drm_plane.c b/drivers/gpu/drm/fsl-dcu/fsl_dcu_drm_plane.c
index 1cb6295..feb7986 100644
--- a/drivers/gpu/drm/fsl-dcu/fsl_dcu_drm_plane.c
+++ b/drivers/gpu/drm/fsl-dcu/fsl_dcu_drm_plane.c
@@ -47,8 +47,11 @@ static int fsl_dcu_drm_plane_atomic_check(struct drm_plane *plane,
switch (fb->pixel_format) {
case DRM_FORMAT_RGB565:
case DRM_FORMAT_RGB888:
+ case DRM_FORMAT_XRGB8888:
case DRM_FORMAT_ARGB8888:
- case DRM_FORMAT_BGRA4444:
+ case DRM_FORMAT_XRGB4444:
+ case DRM_FORMAT_ARGB4444:
+ case DRM_FORMAT_XRGB1555:
case DRM_FORMAT_ARGB1555:
case DRM_FORMAT_YUV422:
return 0;
@@ -81,7 +84,7 @@ static void fsl_dcu_drm_plane_atomic_update(struct drm_plane *plane,
struct drm_plane_state *state = plane->state;
struct drm_framebuffer *fb = plane->state->fb;
struct drm_gem_cma_object *gem;
- unsigned int alpha, bpp;
+ unsigned int alpha = DCU_LAYER_AB_NONE, bpp;
int index;

index = fsl_dcu_drm_plane_index(plane);
@@ -93,27 +96,30 @@ static void fsl_dcu_drm_plane_atomic_update(struct drm_plane *plane,
switch (fb->pixel_format) {
case DRM_FORMAT_RGB565:
bpp = FSL_DCU_RGB565;
- alpha = 0xff;
break;
case DRM_FORMAT_RGB888:
bpp = FSL_DCU_RGB888;
- alpha = 0xff;
break;
case DRM_FORMAT_ARGB8888:
+ alpha = DCU_LAYER_AB_WHOLE_FRAME;
+ /* fall-through */
+ case DRM_FORMAT_XRGB8888:
bpp = FSL_DCU_ARGB8888;
- alpha = 0xff;
break;
- case DRM_FORMAT_BGRA4444:
+ case DRM_FORMAT_ARGB4444:
+ alpha = DCU_LAYER_AB_WHOLE_FRAME;
+ /* fall-through */
+ case DRM_FORMAT_XRGB4444:
bpp = FSL_DCU_ARGB4444;
- alpha = 0xff;
break;
case DRM_FORMAT_ARGB1555:
+ alpha = DCU_LAYER_AB_WHOLE_FRAME;
+ /* fall-through */
+ case DRM_FORMAT_XRGB1555:
bpp = FSL_DCU_ARGB1555;
- alpha = 0xff;
break;
case DRM_FORMAT_YUV422:
bpp = FSL_DCU_YUV422;
- alpha = 0xff;
break;
default:
return;
@@ -129,9 +135,9 @@ static void fsl_dcu_drm_plane_atomic_update(struct drm_plane *plane,
DCU_CTRLDESCLN(index, 3), gem->paddr);
regmap_write(fsl_dev->regmap, DCU_CTRLDESCLN(index, 4),
DCU_LAYER_EN |
- DCU_LAYER_TRANS(alpha) |
+ DCU_LAYER_TRANS(0xff) |
DCU_LAYER_BPP(bpp) |
- DCU_LAYER_AB(0));
+ alpha);
regmap_write(fsl_dev->regmap, DCU_CTRLDESCLN(index, 5),
DCU_LAYER_CKMAX_R(0xFF) |
DCU_LAYER_CKMAX_G(0xFF) |
@@ -199,8 +205,11 @@ static const struct drm_plane_funcs fsl_dcu_drm_plane_funcs = {
static const u32 fsl_dcu_drm_plane_formats[] = {
DRM_FORMAT_RGB565,
DRM_FORMAT_RGB888,
+ DRM_FORMAT_XRGB8888,
DRM_FORMAT_ARGB8888,
+ DRM_FORMAT_XRGB4444,
DRM_FORMAT_ARGB4444,
+ DRM_FORMAT_XRGB1555,
DRM_FORMAT_ARGB1555,
DRM_FORMAT_YUV422,
};
--
2.6.2