[PATCH v4 06/17] drm/mediatek: Support alpha blending in OVL

From: Hsiao Chien Sung
Date: Tue Dec 12 2023 - 07:21:08 EST


Support premultiply and coverage alpha blending in
Overlay.

Signed-off-by: Hsiao Chien Sung <shawn.sung@xxxxxxxxxxxx>
---
drivers/gpu/drm/mediatek/mtk_disp_ovl.c | 73 +++++++++++++++++--------
1 file changed, 51 insertions(+), 22 deletions(-)

diff --git a/drivers/gpu/drm/mediatek/mtk_disp_ovl.c b/drivers/gpu/drm/mediatek/mtk_disp_ovl.c
index 5aaf4342cdbd..66074c2d917c 100644
--- a/drivers/gpu/drm/mediatek/mtk_disp_ovl.c
+++ b/drivers/gpu/drm/mediatek/mtk_disp_ovl.c
@@ -39,6 +39,7 @@
#define DISP_REG_OVL_PITCH_MSB(n) (0x0040 + 0x20 * (n))
#define OVL_PITCH_MSB_2ND_SUBBUF BIT(16)
#define DISP_REG_OVL_PITCH(n) (0x0044 + 0x20 * (n))
+#define OVL_CONST_BLEND BIT(28)
#define DISP_REG_OVL_RDMA_CTRL(n) (0x00c0 + 0x20 * (n))
#define DISP_REG_OVL_RDMA_GMC(n) (0x00c8 + 0x20 * (n))
#define DISP_REG_OVL_ADDR_MT2701 0x0040
@@ -52,13 +53,16 @@
#define GMC_THRESHOLD_HIGH ((1 << GMC_THRESHOLD_BITS) / 4)
#define GMC_THRESHOLD_LOW ((1 << GMC_THRESHOLD_BITS) / 8)

-#define OVL_CON_BYTE_SWAP BIT(24)
-#define OVL_CON_MTX_YUV_TO_RGB (6 << 16)
-#define OVL_CON_CLRFMT_RGB (1 << 12)
-#define OVL_CON_CLRFMT_RGBA8888 (2 << 12)
-#define OVL_CON_CLRFMT_ARGB8888 (3 << 12)
-#define OVL_CON_CLRFMT_UYVY (4 << 12)
-#define OVL_CON_CLRFMT_YUYV (5 << 12)
+#define OVL_CON_CLRFMT_MAN BIT(23)
+#define OVL_CON_BYTE_SWAP BIT(24)
+#define OVL_CON_RGB_SWAP BIT(25)
+#define OVL_CON_CLRFMT_RGB (1 << 12)
+#define OVL_CON_CLRFMT_RGBA8888 (2 << 12)
+#define OVL_CON_CLRFMT_ARGB8888 (3 << 12)
+#define OVL_CON_CLRFMT_PARGB8888 (OVL_CON_CLRFMT_ARGB8888 | OVL_CON_CLRFMT_MAN)
+#define OVL_CON_CLRFMT_UYVY (4 << 12)
+#define OVL_CON_CLRFMT_YUYV (5 << 12)
+#define OVL_CON_MTX_YUV_TO_RGB (6 << 16)
#define OVL_CON_CLRFMT_RGB565(ovl) ((ovl)->data->fmt_rgb565_is_0 ? \
0 : OVL_CON_CLRFMT_RGB)
#define OVL_CON_CLRFMT_RGB888(ovl) ((ovl)->data->fmt_rgb565_is_0 ? \
@@ -208,14 +212,12 @@ void mtk_ovl_clk_disable(struct device *dev)
void mtk_ovl_start(struct device *dev)
{
struct mtk_disp_ovl *ovl = dev_get_drvdata(dev);
+ unsigned int reg = readl(ovl->regs + DISP_REG_OVL_DATAPATH_CON);

- if (ovl->data->smi_id_en) {
- unsigned int reg;
+ if (ovl->data->smi_id_en)
+ reg |= OVL_LAYER_SMI_ID_EN;

- reg = readl(ovl->regs + DISP_REG_OVL_DATAPATH_CON);
- reg = reg | OVL_LAYER_SMI_ID_EN;
- writel_relaxed(reg, ovl->regs + DISP_REG_OVL_DATAPATH_CON);
- }
+ writel_relaxed(reg, ovl->regs + DISP_REG_OVL_DATAPATH_CON);
writel_relaxed(0x1, ovl->regs + DISP_REG_OVL_EN);
}

@@ -274,7 +276,13 @@ void mtk_ovl_config(struct device *dev, unsigned int w,
if (w != 0 && h != 0)
mtk_ddp_write_relaxed(cmdq_pkt, h << 16 | w, &ovl->cmdq_reg, ovl->regs,
DISP_REG_OVL_ROI_SIZE);
- mtk_ddp_write_relaxed(cmdq_pkt, 0x0, &ovl->cmdq_reg, ovl->regs, DISP_REG_OVL_ROI_BGCLR);
+
+ /*
+ * The background color should be opaque black (ARGB),
+ * otherwise there will be no effect with alpha blend
+ */
+ mtk_ddp_write_relaxed(cmdq_pkt, 0xff000000, &ovl->cmdq_reg,
+ ovl->regs, DISP_REG_OVL_ROI_BGCLR);

mtk_ddp_write(cmdq_pkt, 0x1, &ovl->cmdq_reg, ovl->regs, DISP_REG_OVL_RST);
mtk_ddp_write(cmdq_pkt, 0x0, &ovl->cmdq_reg, ovl->regs, DISP_REG_OVL_RST);
@@ -357,7 +365,8 @@ void mtk_ovl_layer_off(struct device *dev, unsigned int idx,
DISP_REG_OVL_RDMA_CTRL(idx));
}

-static unsigned int ovl_fmt_convert(struct mtk_disp_ovl *ovl, unsigned int fmt)
+static unsigned int ovl_fmt_convert(struct mtk_disp_ovl *ovl, unsigned int fmt,
+ unsigned int blend_mode)
{
/* The return value in switch "MEM_MODE_INPUT_FORMAT_XXX"
* is defined in mediatek HW data sheet.
@@ -376,18 +385,30 @@ static unsigned int ovl_fmt_convert(struct mtk_disp_ovl *ovl, unsigned int fmt)
return OVL_CON_CLRFMT_RGB888(ovl) | OVL_CON_BYTE_SWAP;
case DRM_FORMAT_RGBX8888:
case DRM_FORMAT_RGBA8888:
- return OVL_CON_CLRFMT_ARGB8888;
+ return blend_mode == DRM_MODE_BLEND_COVERAGE ?
+ OVL_CON_CLRFMT_ARGB8888 :
+ OVL_CON_CLRFMT_PARGB8888;
case DRM_FORMAT_BGRX8888:
case DRM_FORMAT_BGRA8888:
+ return OVL_CON_BYTE_SWAP |
+ (blend_mode == DRM_MODE_BLEND_COVERAGE ?
+ OVL_CON_CLRFMT_ARGB8888 :
+ OVL_CON_CLRFMT_PARGB8888);
case DRM_FORMAT_BGRA1010102:
return OVL_CON_CLRFMT_ARGB8888 | OVL_CON_BYTE_SWAP;
case DRM_FORMAT_XRGB8888:
case DRM_FORMAT_ARGB8888:
+ return blend_mode == DRM_MODE_BLEND_COVERAGE ?
+ OVL_CON_CLRFMT_RGBA8888 :
+ OVL_CON_CLRFMT_PARGB8888;
case DRM_FORMAT_ARGB2101010:
return OVL_CON_CLRFMT_RGBA8888;
case DRM_FORMAT_XBGR8888:
case DRM_FORMAT_ABGR8888:
- return OVL_CON_CLRFMT_RGBA8888 | OVL_CON_BYTE_SWAP;
+ return OVL_CON_RGB_SWAP |
+ (blend_mode == DRM_MODE_BLEND_COVERAGE ?
+ OVL_CON_CLRFMT_RGBA8888 :
+ OVL_CON_CLRFMT_PARGB8888);
case DRM_FORMAT_UYVY:
return OVL_CON_CLRFMT_UYVY | OVL_CON_MTX_YUV_TO_RGB;
case DRM_FORMAT_YUYV:
@@ -408,6 +429,8 @@ void mtk_ovl_layer_config(struct device *dev, unsigned int idx,
unsigned int fmt = pending->format;
unsigned int offset = (pending->y << 16) | pending->x;
unsigned int src_size = (pending->height << 16) | pending->width;
+ unsigned int blend_mode = state->base.pixel_blend_mode;
+ unsigned int ignore_pixel_alpha = 0;
unsigned int con;
bool is_afbc = pending->modifier != DRM_FORMAT_MOD_LINEAR;
union overlay_pitch {
@@ -425,9 +448,15 @@ void mtk_ovl_layer_config(struct device *dev, unsigned int idx,
return;
}

- con = ovl_fmt_convert(ovl, fmt);
- if (state->base.fb && state->base.fb->format->has_alpha)
- con |= OVL_CON_AEN | OVL_CON_ALPHA;
+ con = ovl_fmt_convert(ovl, fmt, blend_mode);
+ if (state->base.fb) {
+ con |= OVL_CON_AEN;
+ con |= state->base.alpha & OVL_CON_ALPHA;
+ }
+
+ if (blend_mode == DRM_MODE_BLEND_PIXEL_NONE ||
+ (state->base.fb && !state->base.fb->format->has_alpha))
+ ignore_pixel_alpha = OVL_CONST_BLEND;

if (pending->rotation & DRM_MODE_REFLECT_Y) {
con |= OVL_CON_VIRT_FLIP;
@@ -444,8 +473,8 @@ void mtk_ovl_layer_config(struct device *dev, unsigned int idx,

mtk_ddp_write_relaxed(cmdq_pkt, con, &ovl->cmdq_reg, ovl->regs,
DISP_REG_OVL_CON(idx));
- mtk_ddp_write_relaxed(cmdq_pkt, overlay_pitch.split_pitch.lsb, &ovl->cmdq_reg, ovl->regs,
- DISP_REG_OVL_PITCH(idx));
+ mtk_ddp_write_relaxed(cmdq_pkt, overlay_pitch.split_pitch.lsb | ignore_pixel_alpha,
+ &ovl->cmdq_reg, ovl->regs, DISP_REG_OVL_PITCH(idx));
mtk_ddp_write_relaxed(cmdq_pkt, src_size, &ovl->cmdq_reg, ovl->regs,
DISP_REG_OVL_SRC_SIZE(idx));
mtk_ddp_write_relaxed(cmdq_pkt, offset, &ovl->cmdq_reg, ovl->regs,
--
2.18.0