drm/mediatek: gamma: Support SoC specific LUT size

Newer SoCs support a bigger Gamma LUT table: wire up a callback
to retrieve the correct LUT size for each different Gamma IP.
Co-developed-by: Jason-JH.Lin <jason-jh.lin@mediatek.com>
Signed-off-by: Jason-JH.Lin <jason-jh.lin@mediatek.com>
[Angelo: Rewritten commit message/description + porting]
Reviewed-by: Jason-JH.Lin <jason-jh.lin@mediatek.com>
Reviewed-by: Alexandre Mergnat <amergnat@baylibre.com>
Reviewed-by: CK Hu <ck.hu@mediatek.com>
Signed-off-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Link: https://patchwork.kernel.org/project/dri-devel/patch/20231012095736.100784-4-angelogioacchino.delregno@collabora.com/Signed-off-by: Chun-Kuang Hu <chunkuang.hu@kernel.org>

drivers/gpu/drm/mediatek/mtk_disp_aal.c

@@ -19,7 +19,7 @@
 #define AAL_EN						BIT(0)
 #define DISP_AAL_SIZE				0x0030
 #define DISP_AAL_OUTPUT_SIZE			0x04d8
-
+#define DISP_AAL_LUT_SIZE			512
 
 struct mtk_disp_aal_data {
 	bool has_gamma;
@@ -56,6 +56,21 @@ void mtk_aal_config(struct device *dev, unsigned int w,
 	mtk_ddp_write(cmdq_pkt, w << 16 | h, &aal->cmdq_reg, aal->regs, DISP_AAL_OUTPUT_SIZE);
 }
 
+/**
+ * mtk_aal_gamma_get_lut_size() - Get gamma LUT size for AAL
+ * @dev: Pointer to struct device
+ *
+ * Return: 0 if gamma control not supported in AAL or gamma LUT size
+ */
+unsigned int mtk_aal_gamma_get_lut_size(struct device *dev)
+{
+	struct mtk_disp_aal *aal = dev_get_drvdata(dev);
+
+	if (aal->data && aal->data->has_gamma)
+		return DISP_AAL_LUT_SIZE;
+	return 0;
+}
+
 void mtk_aal_gamma_set(struct device *dev, struct drm_crtc_state *state)
 {
 	struct mtk_disp_aal *aal = dev_get_drvdata(dev);

drivers/gpu/drm/mediatek/mtk_disp_drv.h

@@ -17,6 +17,7 @@ void mtk_aal_clk_disable(struct device *dev);
 void mtk_aal_config(struct device *dev, unsigned int w,
 		    unsigned int h, unsigned int vrefresh,
 		    unsigned int bpc, struct cmdq_pkt *cmdq_pkt);
+unsigned int mtk_aal_gamma_get_lut_size(struct device *dev);
 void mtk_aal_gamma_set(struct device *dev, struct drm_crtc_state *state);
 void mtk_aal_start(struct device *dev);
 void mtk_aal_stop(struct device *dev);
@@ -55,6 +56,7 @@ void mtk_gamma_clk_disable(struct device *dev);
 void mtk_gamma_config(struct device *dev, unsigned int w,
 		      unsigned int h, unsigned int vrefresh,
 		      unsigned int bpc, struct cmdq_pkt *cmdq_pkt);
+unsigned int mtk_gamma_get_lut_size(struct device *dev);
 void mtk_gamma_set(struct device *dev, struct drm_crtc_state *state);
 void mtk_gamma_set_common(struct device *dev, void __iomem *regs, struct drm_crtc_state *state);
 void mtk_gamma_start(struct device *dev);

drivers/gpu/drm/mediatek/mtk_disp_gamma.c

@@ -28,6 +28,7 @@
 struct mtk_disp_gamma_data {
 	bool has_dither;
 	bool lut_diff;
+	u16 lut_size;
 };
 
 /*
@@ -54,6 +55,15 @@ void mtk_gamma_clk_disable(struct device *dev)
 	clk_disable_unprepare(gamma->clk);
 }
 
+unsigned int mtk_gamma_get_lut_size(struct device *dev)
+{
+	struct mtk_disp_gamma *gamma = dev_get_drvdata(dev);
+
+	if (gamma && gamma->data)
+		return gamma->data->lut_size;
+	return 0;
+}
+
 void mtk_gamma_set_common(struct device *dev, void __iomem *regs, struct drm_crtc_state *state)
 {
 	struct mtk_disp_gamma *gamma;
@@ -61,6 +71,7 @@ void mtk_gamma_set_common(struct device *dev, void __iomem *regs, struct drm_crt
 	struct drm_color_lut *lut;
 	void __iomem *lut_base;
 	bool lut_diff;
+	u16 lut_size;
 	u32 word;
 	u32 diff[3] = {0};
 
@@ -71,17 +82,20 @@ void mtk_gamma_set_common(struct device *dev, void __iomem *regs, struct drm_crt
 	/* If we're called from AAL, dev is NULL */
 	gamma = dev ? dev_get_drvdata(dev) : NULL;
 
-	if (gamma && gamma->data)
+	if (gamma && gamma->data) {
 		lut_diff = gamma->data->lut_diff;
-	else
+		lut_size = gamma->data->lut_size;
+	} else {
 		lut_diff = false;
+		lut_size = 512;
+	}
 
 	reg = readl(regs + DISP_GAMMA_CFG);
 	reg = reg | GAMMA_LUT_EN;
 	writel(reg, regs + DISP_GAMMA_CFG);
 	lut_base = regs + DISP_GAMMA_LUT;
 	lut = (struct drm_color_lut *)state->gamma_lut->data;
-	for (i = 0; i < MTK_LUT_SIZE; i++) {
+	for (i = 0; i < lut_size; i++) {
 		if (!lut_diff || (i % 2 == 0)) {
 			word = (((lut[i].red >> 6) & LUT_10BIT_MASK) << 20) +
 				(((lut[i].green >> 6) & LUT_10BIT_MASK) << 10) +
@@ -196,10 +210,12 @@ static void mtk_disp_gamma_remove(struct platform_device *pdev)
 
 static const struct mtk_disp_gamma_data mt8173_gamma_driver_data = {
 	.has_dither = true,
+	.lut_size = 512,
 };
 
 static const struct mtk_disp_gamma_data mt8183_gamma_driver_data = {
 	.lut_diff = true,
+	.lut_size = 512,
 };
 
 static const struct of_device_id mtk_disp_gamma_driver_dt_match[] = {

drivers/gpu/drm/mediatek/mtk_drm_crtc.c

@@ -1002,8 +1002,12 @@ int mtk_drm_crtc_create(struct drm_device *drm_dev,
 		mtk_crtc->ddp_comp[i] = comp;
 
 		if (comp->funcs) {
-			if (comp->funcs->gamma_set)
-				gamma_lut_size = MTK_LUT_SIZE;
+			if (comp->funcs->gamma_set && comp->funcs->gamma_get_lut_size) {
+				unsigned int lut_sz = mtk_ddp_gamma_get_lut_size(comp);
+
+				if (lut_sz)
+					gamma_lut_size = lut_sz;
+			}
 
 			if (comp->funcs->ctm_set)
 				has_ctm = true;

drivers/gpu/drm/mediatek/mtk_drm_crtc.h

@@ -11,7 +11,6 @@
 #include "mtk_drm_drv.h"
 #include "mtk_drm_plane.h"
 
-#define MTK_LUT_SIZE	512
 #define MTK_MAX_BPC	10
 #define MTK_MIN_BPC	3
 

drivers/gpu/drm/mediatek/mtk_drm_ddp_comp.c

@@ -271,6 +271,7 @@ static void mtk_ufoe_start(struct device *dev)
 static const struct mtk_ddp_comp_funcs ddp_aal = {
 	.clk_enable = mtk_aal_clk_enable,
 	.clk_disable = mtk_aal_clk_disable,
+	.gamma_get_lut_size = mtk_aal_gamma_get_lut_size,
 	.gamma_set = mtk_aal_gamma_set,
 	.config = mtk_aal_config,
 	.start = mtk_aal_start,
@@ -324,6 +325,7 @@ static const struct mtk_ddp_comp_funcs ddp_dsi = {
 static const struct mtk_ddp_comp_funcs ddp_gamma = {
 	.clk_enable = mtk_gamma_clk_enable,
 	.clk_disable = mtk_gamma_clk_disable,
+	.gamma_get_lut_size = mtk_gamma_get_lut_size,
 	.gamma_set = mtk_gamma_set,
 	.config = mtk_gamma_config,
 	.start = mtk_gamma_start,

drivers/gpu/drm/mediatek/mtk_drm_ddp_comp.h

@@ -67,6 +67,7 @@ struct mtk_ddp_comp_funcs {
 	void (*layer_config)(struct device *dev, unsigned int idx,
 			     struct mtk_plane_state *state,
 			     struct cmdq_pkt *cmdq_pkt);
+	unsigned int (*gamma_get_lut_size)(struct device *dev);
 	void (*gamma_set)(struct device *dev,
 			  struct drm_crtc_state *state);
 	void (*bgclr_in_on)(struct device *dev);
@@ -188,6 +189,14 @@ static inline void mtk_ddp_comp_layer_config(struct mtk_ddp_comp *comp,
 		comp->funcs->layer_config(comp->dev, idx, state, cmdq_pkt);
 }
 
+static inline unsigned int mtk_ddp_gamma_get_lut_size(struct mtk_ddp_comp *comp)
+{
+	if (comp->funcs && comp->funcs->gamma_get_lut_size)
+		return comp->funcs->gamma_get_lut_size(comp->dev);
+
+	return 0;
+}
+
 static inline void mtk_ddp_gamma_set(struct mtk_ddp_comp *comp,
 				     struct drm_crtc_state *state)
 {