[PATCH v4 5/6] drm/mediatek: add DSC support for mt8195

[jason-jh.lin]

Add DSC into mtk_drm_ddp_comp to support for mt8195.

DSC is designed for real-time systems with real-time compression,
transmission, decompression and display.
The DSC standard is a specification of the algorithms used for
compressing and decompressing image display streams, including
the specification of the syntax and semantics of the compressed
video bit stream.

Signed-off-by: jason-jh.lin <jason-jh.lin at mediatek.com>
---
This patch is base on [1]

[1]add mt8195 SoC DRM binding
- https://patchwork.kernel.org/project/linux-mediatek/list/?series=519597
---
 drivers/gpu/drm/mediatek/mtk_drm_ddp_comp.c | 46 +++++++++++++++++++++
 drivers/gpu/drm/mediatek/mtk_drm_ddp_comp.h |  1 +
 drivers/gpu/drm/mediatek/mtk_drm_drv.c      |  2 +
 3 files changed, 49 insertions(+)

diff --git a/drivers/gpu/drm/mediatek/mtk_drm_ddp_comp.c b/drivers/gpu/drm/mediatek/mtk_drm_ddp_comp.c
index 75bc00e17fc4..6f4a9b8c9914 100644
--- a/drivers/gpu/drm/mediatek/mtk_drm_ddp_comp.c
+++ b/drivers/gpu/drm/mediatek/mtk_drm_ddp_comp.c
@@ -65,6 +65,12 @@
 #define DITHER_ADD_LSHIFT_G(x)			(((x) & 0x7) << 4)
 #define DITHER_ADD_RSHIFT_G(x)			(((x) & 0x7) << 0)
 
+#define DISP_REG_DSC_CON			0x0000
+#define DSC_EN					BIT(0)
+#define DSC_DUAL_INOUT				BIT(2)
+#define DSC_BYPASS				BIT(4)
+#define DSC_UFOE_SEL				BIT(16)
+
 struct mtk_ddp_comp_dev {
 	struct clk *clk;
 	void __iomem *regs;
@@ -246,6 +252,35 @@ static void mtk_dither_stop(struct device *dev)
 	writel_relaxed(0x0, priv->regs + DISP_DITHER_EN);
 }
 
+static void mtk_dsc_config(struct device *dev, unsigned int w,
+			   unsigned int h, unsigned int vrefresh,
+			   unsigned int bpc, struct cmdq_pkt *cmdq_pkt)
+{
+	struct mtk_ddp_comp_dev *priv = dev_get_drvdata(dev);
+
+	/* dsc bypass mode */
+	mtk_ddp_write_mask(cmdq_pkt, DSC_BYPASS, &priv->cmdq_reg, priv->regs,
+			   DISP_REG_DSC_CON, DSC_BYPASS);
+	mtk_ddp_write_mask(cmdq_pkt, DSC_UFOE_SEL, &priv->cmdq_reg, priv->regs,
+			   DISP_REG_DSC_CON, DSC_UFOE_SEL);
+	mtk_ddp_write_mask(cmdq_pkt, DSC_DUAL_INOUT, &priv->cmdq_reg, priv->regs,
+			   DISP_REG_DSC_CON, DSC_DUAL_INOUT);
+}
+
+static void mtk_dsc_start(struct device *dev)
+{
+	struct mtk_ddp_comp_dev *priv = dev_get_drvdata(dev);
+
+	writel_relaxed(DSC_EN, &priv->regs + DISP_REG_DSC_CON);
+}
+
+static void mtk_dsc_stop(struct device *dev)
+{
+	struct mtk_ddp_comp_dev *priv = dev_get_drvdata(dev);
+
+	writel_relaxed(0x0, priv->regs + DISP_REG_DSC_CON);
+}
+
 static const struct mtk_ddp_comp_funcs ddp_aal = {
 	.clk_enable = mtk_ddp_clk_enable,
 	.clk_disable = mtk_ddp_clk_disable,
@@ -284,6 +319,14 @@ static const struct mtk_ddp_comp_funcs ddp_dpi = {
 	.stop = mtk_dpi_stop,
 };
 
+static const struct mtk_ddp_comp_funcs ddp_dsc = {
+	.clk_enable = mtk_ddp_clk_enable,
+	.clk_disable = mtk_ddp_clk_disable,
+	.config = mtk_dsc_config,
+	.start = mtk_dsc_start,
+	.stop = mtk_dsc_stop,
+};
+
 static const struct mtk_ddp_comp_funcs ddp_dsi = {
 	.start = mtk_dsi_ddp_start,
 	.stop = mtk_dsi_ddp_stop,
@@ -356,6 +399,7 @@ static const char * const mtk_ddp_comp_stem[MTK_DDP_COMP_TYPE_MAX] = {
 	[MTK_DISP_MUTEX] = "mutex",
 	[MTK_DISP_OD] = "od",
 	[MTK_DISP_BLS] = "bls",
+	[MTK_DISP_DSC] = "dsc",
 };
 
 struct mtk_ddp_comp_match {
@@ -374,6 +418,8 @@ static const struct mtk_ddp_comp_match mtk_ddp_matches[DDP_COMPONENT_ID_MAX] = {
 	[DDP_COMPONENT_DITHER]	= { MTK_DISP_DITHER,	0, &ddp_dither },
 	[DDP_COMPONENT_DPI0]	= { MTK_DPI,		0, &ddp_dpi },
 	[DDP_COMPONENT_DPI1]	= { MTK_DPI,		1, &ddp_dpi },
+	[DDP_COMPONENT_DSC0]	= { MTK_DISP_DSC,	0, &ddp_dsc },
+	[DDP_COMPONENT_DSC1]	= { MTK_DISP_DSC,	1, &ddp_dsc },
 	[DDP_COMPONENT_DSI0]	= { MTK_DSI,		0, &ddp_dsi },
 	[DDP_COMPONENT_DSI1]	= { MTK_DSI,		1, &ddp_dsi },
 	[DDP_COMPONENT_DSI2]	= { MTK_DSI,		2, &ddp_dsi },
diff --git a/drivers/gpu/drm/mediatek/mtk_drm_ddp_comp.h b/drivers/gpu/drm/mediatek/mtk_drm_ddp_comp.h
index bb914d976cf5..661fb620e266 100644
--- a/drivers/gpu/drm/mediatek/mtk_drm_ddp_comp.h
+++ b/drivers/gpu/drm/mediatek/mtk_drm_ddp_comp.h
@@ -34,6 +34,7 @@ enum mtk_ddp_comp_type {
 	MTK_DISP_MUTEX,
 	MTK_DISP_OD,
 	MTK_DISP_BLS,
+	MTK_DISP_DSC,
 	MTK_DDP_COMP_TYPE_MAX,
 };
 
diff --git a/drivers/gpu/drm/mediatek/mtk_drm_drv.c b/drivers/gpu/drm/mediatek/mtk_drm_drv.c
index d6f6d1bdad85..0f6bb4bdc58a 100644
--- a/drivers/gpu/drm/mediatek/mtk_drm_drv.c
+++ b/drivers/gpu/drm/mediatek/mtk_drm_drv.c
@@ -446,6 +446,8 @@ static const struct of_device_id mtk_ddp_comp_dt_ids[] = {
 	  .data = (void *)MTK_DISP_GAMMA, },
 	{ .compatible = "mediatek,mt8183-disp-dither",
 	  .data = (void *)MTK_DISP_DITHER },
+	{ .compatible = "mediatek,mt8195-disp-dsc",
+	  .data = (void *)MTK_DISP_DSC },
 	{ .compatible = "mediatek,mt8173-disp-ufoe",
 	  .data = (void *)MTK_DISP_UFOE },
 	{ .compatible = "mediatek,mt2701-dsi",
-- 
2.18.0