[PATCH v8 00/13] MediaTek DDP GAMMA - 12-bit LUT support

[PATCH v8 00/13] MediaTek DDP GAMMA - 12-bit LUT support

[AngeloGioacchino Del Regno]

Changes in v8:
 - Changed lut_size to be a mtk_disp_gamma_set_common() function
   parameter to pass lut size from AAL

Changes in v7:
 - Added check for NULL dev for AAL-gamma case
 - Added get_lut_size callback for AAL-gamma
 - Added comment to clarify SoC 10/12 bits support and old vs new
   register layout as suggested by Alexandre M.

Changes in v6:
 - Fixed smatch warning in patch 11/11, ref.:
   https://lore.kernel.org/all/202306101458.lRXHEE0Z-lkp@intel.com/

Changes in v5:
 - Removed incorrect comment on default LUT size and bits
 - Removed useless check for num_lut_banks
 - Added comment about CMDQ implementation on patch 5
 - Evaluated passing lut size/bits from AAL, idea discarded as
   the implementation would be rather tricky while bringing no
   benefits.

Changes in v4:
 - Fixed assignment typo appeared in v3

Changes in v3:
 - Fixed issues due to variables renaming during cleanup (oops)
 - This is actually the right series, since v2 was taken from the
   wrong kernel tree.... :-)

Changes in v2:
 - Added explicit inclusion of linux/bitfield.h in patch [06/11]

This series adds support for GAMMA IP requiring and/or supporting
a 12-bits LUT using a slightly different register layout and programming
sequence for multiple LUT banks: this IP version is currently found
on a number of SoCs, not only including the Chromebook/IoT oriented
Kompanio 1200/1380 MT8195/MT8195T, but also Smartphone chips such as
the Dimensity 9200 (MT6985) and others.

This series was tested on MT8195, MT8192, MT8173, MT6795:
 * MT6795, MT8192, MT8173: No regression, works fine.
 * MT8195: Color correction is finally working!

AngeloGioacchino Del Regno (12):
  drm/mediatek: gamma: Reduce indentation in mtk_gamma_set_common()
  drm/mediatek: gamma: Support SoC specific LUT size
  drm/mediatek: gamma: Improve and simplify HW LUT calculation
  drm/mediatek: gamma: Enable the Gamma LUT table only after programming
  drm/mediatek: gamma: Use bitfield macros
  drm/mediatek: gamma: Support specifying number of bits per LUT
    component
  drm/mediatek: gamma: Support multi-bank gamma LUT
  drm/mediatek: gamma: Add support for 12-bit LUT and MT8195
  drm/mediatek: gamma: Make sure relay mode is disabled
  drm/mediatek: gamma: Program gamma LUT type for descending or rising
  drm/mediatek: mtk_disp_aal: Rewrite kerneldoc for struct mtk_disp_aal
  drm/mediatek: mtk_disp_gamma: Add kerneldoc for struct mtk_disp_gamma

Jason-JH.Lin (1):
  drm/mediatek: gamma: Adjust mtk_drm_gamma_set_common parameters

 drivers/gpu/drm/mediatek/mtk_disp_aal.c     |  27 ++-
 drivers/gpu/drm/mediatek/mtk_disp_drv.h     |   5 +-
 drivers/gpu/drm/mediatek/mtk_disp_gamma.c   | 214 +++++++++++++++++---
 drivers/gpu/drm/mediatek/mtk_drm_crtc.c     |   8 +-
 drivers/gpu/drm/mediatek/mtk_drm_crtc.h     |   1 -
 drivers/gpu/drm/mediatek/mtk_drm_ddp_comp.c |   2 +
 drivers/gpu/drm/mediatek/mtk_drm_ddp_comp.h |   9 +
 7 files changed, 224 insertions(+), 42 deletions(-)

-- 
2.41.0

[PATCH v8 01/13] drm/mediatek: gamma: Adjust mtk_drm_gamma_set_common parameters

[AngeloGioacchino Del Regno]

From: "Jason-JH.Lin" <jason-jh.lin@mediatek.com>

Adjust the parameters in mtk_drm_gamma_set_common()
  - add (struct device *dev) to get lut_diff from gamma's driver data
  - remove (bool lut_diff) and use false as default value in the function

Signed-off-by: Jason-JH.Lin <jason-jh.lin@mediatek.com>
Signed-off-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Reviewed-by: Alexandre Mergnat <amergnat@baylibre.com>
---
 drivers/gpu/drm/mediatek/mtk_disp_aal.c   |  2 +-
 drivers/gpu/drm/mediatek/mtk_disp_drv.h   |  2 +-
 drivers/gpu/drm/mediatek/mtk_disp_gamma.c | 18 ++++++++++++------
 3 files changed, 14 insertions(+), 8 deletions(-)

diff --git a/drivers/gpu/drm/mediatek/mtk_disp_aal.c b/drivers/gpu/drm/mediatek/mtk_disp_aal.c
index cdbec79474d1..2f602f1f1c49 100644
--- a/drivers/gpu/drm/mediatek/mtk_disp_aal.c
+++ b/drivers/gpu/drm/mediatek/mtk_disp_aal.c
@@ -66,7 +66,7 @@ void mtk_aal_gamma_set(struct device *dev, struct drm_crtc_state *state)
 	struct mtk_disp_aal *aal = dev_get_drvdata(dev);
 
 	if (aal->data && aal->data->has_gamma)
-		mtk_gamma_set_common(aal->regs, state, false);
+		mtk_gamma_set_common(NULL, aal->regs, state);
 }
 
 void mtk_aal_start(struct device *dev)
diff --git a/drivers/gpu/drm/mediatek/mtk_disp_drv.h b/drivers/gpu/drm/mediatek/mtk_disp_drv.h
index 2254038519e1..75045932353e 100644
--- a/drivers/gpu/drm/mediatek/mtk_disp_drv.h
+++ b/drivers/gpu/drm/mediatek/mtk_disp_drv.h
@@ -54,7 +54,7 @@ void mtk_gamma_config(struct device *dev, unsigned int w,
 		      unsigned int h, unsigned int vrefresh,
 		      unsigned int bpc, struct cmdq_pkt *cmdq_pkt);
 void mtk_gamma_set(struct device *dev, struct drm_crtc_state *state);
-void mtk_gamma_set_common(void __iomem *regs, struct drm_crtc_state *state, bool lut_diff);
+void mtk_gamma_set_common(struct device *dev, void __iomem *regs, struct drm_crtc_state *state);
 void mtk_gamma_start(struct device *dev);
 void mtk_gamma_stop(struct device *dev);
 
diff --git a/drivers/gpu/drm/mediatek/mtk_disp_gamma.c b/drivers/gpu/drm/mediatek/mtk_disp_gamma.c
index 7746dceadb20..d42cc0698d83 100644
--- a/drivers/gpu/drm/mediatek/mtk_disp_gamma.c
+++ b/drivers/gpu/drm/mediatek/mtk_disp_gamma.c
@@ -54,14 +54,24 @@ void mtk_gamma_clk_disable(struct device *dev)
 	clk_disable_unprepare(gamma->clk);
 }
 
-void mtk_gamma_set_common(void __iomem *regs, struct drm_crtc_state *state, bool lut_diff)
+void mtk_gamma_set_common(struct device *dev, void __iomem *regs, struct drm_crtc_state *state)
 {
+	struct mtk_disp_gamma *gamma;
 	unsigned int i, reg;
 	struct drm_color_lut *lut;
 	void __iomem *lut_base;
+	bool lut_diff;
 	u32 word;
 	u32 diff[3] = {0};
 
+	/* If we're called from AAL, dev is NULL */
+	gamma = dev ? dev_get_drvdata(dev) : NULL;
+
+	if (gamma && gamma->data)
+		lut_diff = gamma->data->lut_diff;
+	else
+		lut_diff = false;
+
 	if (state->gamma_lut) {
 		reg = readl(regs + DISP_GAMMA_CFG);
 		reg = reg | GAMMA_LUT_EN;
@@ -91,12 +101,8 @@ void mtk_gamma_set_common(void __iomem *regs, struct drm_crtc_state *state, bool
 void mtk_gamma_set(struct device *dev, struct drm_crtc_state *state)
 {
 	struct mtk_disp_gamma *gamma = dev_get_drvdata(dev);
-	bool lut_diff = false;
-
-	if (gamma->data)
-		lut_diff = gamma->data->lut_diff;
 
-	mtk_gamma_set_common(gamma->regs, state, lut_diff);
+	mtk_gamma_set_common(dev, gamma->regs, state);
 }
 
 void mtk_gamma_config(struct device *dev, unsigned int w,
-- 
2.41.0

[PATCH v8 02/13] drm/mediatek: gamma: Reduce indentation in mtk_gamma_set_common()

[AngeloGioacchino Del Regno]

Invert the check for state->gamma_lut and move it at the beginning
of the function to reduce indentation: this prepares the code for
keeping readability on later additions.

This commit brings no functional changes.

Signed-off-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Reviewed-by: Jason-JH.Lin <jason-jh.lin@mediatek.com>
Reviewed-by: Alexandre Mergnat <amergnat@baylibre.com>
---
 drivers/gpu/drm/mediatek/mtk_disp_gamma.c | 45 ++++++++++++-----------
 1 file changed, 23 insertions(+), 22 deletions(-)

diff --git a/drivers/gpu/drm/mediatek/mtk_disp_gamma.c b/drivers/gpu/drm/mediatek/mtk_disp_gamma.c
index d42cc0698d83..47751864bd5c 100644
--- a/drivers/gpu/drm/mediatek/mtk_disp_gamma.c
+++ b/drivers/gpu/drm/mediatek/mtk_disp_gamma.c
@@ -64,6 +64,10 @@ void mtk_gamma_set_common(struct device *dev, void __iomem *regs, struct drm_crt
 	u32 word;
 	u32 diff[3] = {0};
 
+	/* If there's no gamma lut there's nothing to do here. */
+	if (!state->gamma_lut)
+		return;
+
 	/* If we're called from AAL, dev is NULL */
 	gamma = dev ? dev_get_drvdata(dev) : NULL;
 
@@ -72,29 +76,26 @@ void mtk_gamma_set_common(struct device *dev, void __iomem *regs, struct drm_crt
 	else
 		lut_diff = false;
 
-	if (state->gamma_lut) {
-		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++) {
-
-			if (!lut_diff || (i % 2 == 0)) {
-				word = (((lut[i].red >> 6) & LUT_10BIT_MASK) << 20) +
-					(((lut[i].green >> 6) & LUT_10BIT_MASK) << 10) +
-					((lut[i].blue >> 6) & LUT_10BIT_MASK);
-			} else {
-				diff[0] = (lut[i].red >> 6) - (lut[i - 1].red >> 6);
-				diff[1] = (lut[i].green >> 6) - (lut[i - 1].green >> 6);
-				diff[2] = (lut[i].blue >> 6) - (lut[i - 1].blue >> 6);
-
-				word = ((diff[0] & LUT_10BIT_MASK) << 20) +
-					((diff[1] & LUT_10BIT_MASK) << 10) +
-					(diff[2] & LUT_10BIT_MASK);
-			}
-			writel(word, (lut_base + i * 4));
+	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++) {
+		if (!lut_diff || (i % 2 == 0)) {
+			word = (((lut[i].red >> 6) & LUT_10BIT_MASK) << 20) +
+				(((lut[i].green >> 6) & LUT_10BIT_MASK) << 10) +
+				((lut[i].blue >> 6) & LUT_10BIT_MASK);
+		} else {
+			diff[0] = (lut[i].red >> 6) - (lut[i - 1].red >> 6);
+			diff[1] = (lut[i].green >> 6) - (lut[i - 1].green >> 6);
+			diff[2] = (lut[i].blue >> 6) - (lut[i - 1].blue >> 6);
+
+			word = ((diff[0] & LUT_10BIT_MASK) << 20) +
+				((diff[1] & LUT_10BIT_MASK) << 10) +
+				(diff[2] & LUT_10BIT_MASK);
 		}
+		writel(word, (lut_base + i * 4));
 	}
 }
 
-- 
2.41.0

[PATCH v8 03/13] drm/mediatek: gamma: Support SoC specific LUT size

[AngeloGioacchino Del Regno]

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]
Signed-off-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Reviewed-by: Jason-JH.Lin <jason-jh.lin@mediatek.com>
Reviewed-by: Alexandre Mergnat <amergnat@baylibre.com>
---
 drivers/gpu/drm/mediatek/mtk_disp_aal.c     | 19 +++++++++++++++++--
 drivers/gpu/drm/mediatek/mtk_disp_drv.h     |  5 ++++-
 drivers/gpu/drm/mediatek/mtk_disp_gamma.c   | 17 ++++++++++++++---
 drivers/gpu/drm/mediatek/mtk_drm_crtc.c     |  8 ++++++--
 drivers/gpu/drm/mediatek/mtk_drm_crtc.h     |  1 -
 drivers/gpu/drm/mediatek/mtk_drm_ddp_comp.c |  2 ++
 drivers/gpu/drm/mediatek/mtk_drm_ddp_comp.h |  9 +++++++++
 7 files changed, 52 insertions(+), 9 deletions(-)

diff --git a/drivers/gpu/drm/mediatek/mtk_disp_aal.c b/drivers/gpu/drm/mediatek/mtk_disp_aal.c
index 2f602f1f1c49..e390ccfdee18 100644
--- a/drivers/gpu/drm/mediatek/mtk_disp_aal.c
+++ b/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;
@@ -61,12 +61,27 @@ 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);
 
 	if (aal->data && aal->data->has_gamma)
-		mtk_gamma_set_common(NULL, aal->regs, state);
+		mtk_gamma_set_common(NULL, aal->regs, state, DISP_AAL_LUT_SIZE);
 }
 
 void mtk_aal_start(struct device *dev)
diff --git a/drivers/gpu/drm/mediatek/mtk_disp_drv.h b/drivers/gpu/drm/mediatek/mtk_disp_drv.h
index 75045932353e..f57aec688e25 100644
--- a/drivers/gpu/drm/mediatek/mtk_disp_drv.h
+++ b/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);
@@ -53,8 +54,10 @@ 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_set_common(struct device *dev, void __iomem *regs,
+			  struct drm_crtc_state *state, u16 lut_size);
 void mtk_gamma_start(struct device *dev);
 void mtk_gamma_stop(struct device *dev);
 
diff --git a/drivers/gpu/drm/mediatek/mtk_disp_gamma.c b/drivers/gpu/drm/mediatek/mtk_disp_gamma.c
index 47751864bd5c..bfdecb278b45 100644
--- a/drivers/gpu/drm/mediatek/mtk_disp_gamma.c
+++ b/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;
 };
 
 /*
@@ -54,7 +55,15 @@ void mtk_gamma_clk_disable(struct device *dev)
 	clk_disable_unprepare(gamma->clk);
 }
 
-void mtk_gamma_set_common(struct device *dev, void __iomem *regs, struct drm_crtc_state *state)
+unsigned int mtk_gamma_get_lut_size(struct device *dev)
+{
+	struct mtk_disp_gamma *gamma = dev_get_drvdata(dev);
+
+	return gamma->data->lut_size;
+}
+
+void mtk_gamma_set_common(struct device *dev, void __iomem *regs,
+			  struct drm_crtc_state *state, u16 lut_size)
 {
 	struct mtk_disp_gamma *gamma;
 	unsigned int i, reg;
@@ -81,7 +90,7 @@ void mtk_gamma_set_common(struct device *dev, void __iomem *regs, struct drm_crt
 	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) +
@@ -103,7 +112,7 @@ void mtk_gamma_set(struct device *dev, struct drm_crtc_state *state)
 {
 	struct mtk_disp_gamma *gamma = dev_get_drvdata(dev);
 
-	mtk_gamma_set_common(dev, gamma->regs, state);
+	mtk_gamma_set_common(dev, gamma->regs, state, gamma->data->lut_size);
 }
 
 void mtk_gamma_config(struct device *dev, unsigned int w,
@@ -198,10 +207,12 @@ static int 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[] = {
diff --git a/drivers/gpu/drm/mediatek/mtk_drm_crtc.c b/drivers/gpu/drm/mediatek/mtk_drm_crtc.c
index 8a43656ecc30..ebe0cc3a1a4c 100644
--- a/drivers/gpu/drm/mediatek/mtk_drm_crtc.c
+++ b/drivers/gpu/drm/mediatek/mtk_drm_crtc.c
@@ -959,8 +959,12 @@ 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;
diff --git a/drivers/gpu/drm/mediatek/mtk_drm_crtc.h b/drivers/gpu/drm/mediatek/mtk_drm_crtc.h
index 3e9046993d09..b2e50292e57d 100644
--- a/drivers/gpu/drm/mediatek/mtk_drm_crtc.h
+++ b/drivers/gpu/drm/mediatek/mtk_drm_crtc.h
@@ -10,7 +10,6 @@
 #include "mtk_drm_ddp_comp.h"
 #include "mtk_drm_plane.h"
 
-#define MTK_LUT_SIZE	512
 #define MTK_MAX_BPC	10
 #define MTK_MIN_BPC	3
 
diff --git a/drivers/gpu/drm/mediatek/mtk_drm_ddp_comp.c b/drivers/gpu/drm/mediatek/mtk_drm_ddp_comp.c
index f114da4d36a9..f3212e08f2cd 100644
--- a/drivers/gpu/drm/mediatek/mtk_drm_ddp_comp.c
+++ b/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,
@@ -322,6 +323,7 @@ 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,
diff --git a/drivers/gpu/drm/mediatek/mtk_drm_ddp_comp.h b/drivers/gpu/drm/mediatek/mtk_drm_ddp_comp.h
index febcaeef16a1..c1355960e195 100644
--- a/drivers/gpu/drm/mediatek/mtk_drm_ddp_comp.h
+++ b/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);
@@ -186,6 +187,14 @@ 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)
 {
-- 
2.41.0

[PATCH v8 04/13] drm/mediatek: gamma: Improve and simplify HW LUT calculation

[AngeloGioacchino Del Regno]

Use drm_color_lut_extract() to avoid open-coding the bits reduction
calculations for each color channel and use a struct drm_color_lut
to temporarily store the information instead of an array of u32.

Also, slightly improve the precision of the HW LUT calculation in the
LUT DIFF case by performing the subtractions on the 16-bits values and
doing the 10 bits conversion later.

Signed-off-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Reviewed-by: Jason-JH.Lin <jason-jh.lin@mediatek.com>
Reviewed-by: Alexandre Mergnat <amergnat@baylibre.com>
---
 drivers/gpu/drm/mediatek/mtk_disp_gamma.c | 30 +++++++++++++++--------
 1 file changed, 20 insertions(+), 10 deletions(-)

diff --git a/drivers/gpu/drm/mediatek/mtk_disp_gamma.c b/drivers/gpu/drm/mediatek/mtk_disp_gamma.c
index bfdecb278b45..1e21dd92c88b 100644
--- a/drivers/gpu/drm/mediatek/mtk_disp_gamma.c
+++ b/drivers/gpu/drm/mediatek/mtk_disp_gamma.c
@@ -71,7 +71,6 @@ void mtk_gamma_set_common(struct device *dev, void __iomem *regs,
 	void __iomem *lut_base;
 	bool lut_diff;
 	u32 word;
-	u32 diff[3] = {0};
 
 	/* If there's no gamma lut there's nothing to do here. */
 	if (!state->gamma_lut)
@@ -91,18 +90,29 @@ void mtk_gamma_set_common(struct device *dev, void __iomem *regs,
 	lut_base = regs + DISP_GAMMA_LUT;
 	lut = (struct drm_color_lut *)state->gamma_lut->data;
 	for (i = 0; i < lut_size; i++) {
+		struct drm_color_lut diff, hwlut;
+
+		hwlut.red = drm_color_lut_extract(lut[i].red, 10);
+		hwlut.green = drm_color_lut_extract(lut[i].green, 10);
+		hwlut.blue = drm_color_lut_extract(lut[i].blue, 10);
+
 		if (!lut_diff || (i % 2 == 0)) {
-			word = (((lut[i].red >> 6) & LUT_10BIT_MASK) << 20) +
-				(((lut[i].green >> 6) & LUT_10BIT_MASK) << 10) +
-				((lut[i].blue >> 6) & LUT_10BIT_MASK);
+			word = hwlut.red << 20 +
+			       hwlut.green << 10 +
+			       hwlut.red;
 		} else {
-			diff[0] = (lut[i].red >> 6) - (lut[i - 1].red >> 6);
-			diff[1] = (lut[i].green >> 6) - (lut[i - 1].green >> 6);
-			diff[2] = (lut[i].blue >> 6) - (lut[i - 1].blue >> 6);
+			diff.red = lut[i].red - lut[i - 1].red;
+			diff.red = drm_color_lut_extract(diff.red, 10);
+
+			diff.green = lut[i].green - lut[i - 1].green;
+			diff.green = drm_color_lut_extract(diff.green, 10);
+
+			diff.blue = lut[i].blue - lut[i - 1].blue;
+			diff.blue = drm_color_lut_extract(diff.blue, 10);
 
-			word = ((diff[0] & LUT_10BIT_MASK) << 20) +
-				((diff[1] & LUT_10BIT_MASK) << 10) +
-				(diff[2] & LUT_10BIT_MASK);
+			word = diff.blue << 20 +
+			       diff.green << 10 +
+			       diff.red;
 		}
 		writel(word, (lut_base + i * 4));
 	}
-- 
2.41.0

[PATCH v8 05/13] drm/mediatek: gamma: Enable the Gamma LUT table only after programming

[AngeloGioacchino Del Regno]

Move the write to DISP_GAMMA_CFG to enable the Gamma LUT to after
programming the actual table to avoid potential visual glitches during
table modification.

Note:
GAMMA should get enabled in between vblanks, but this requires many
efforts in order to make this happen, as that requires migrating all
of the writes to make use of CMDQ instead of cpu writes and that's
not trivial. For this reason, this patch only moves the LUT enable.
The CMDQ rework will come at a later time.

Signed-off-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Reviewed-by: Jason-JH.Lin <jason-jh.lin@mediatek.com>
Reviewed-by: Alexandre Mergnat <amergnat@baylibre.com>
---
 drivers/gpu/drm/mediatek/mtk_disp_gamma.c | 13 ++++++++-----
 1 file changed, 8 insertions(+), 5 deletions(-)

diff --git a/drivers/gpu/drm/mediatek/mtk_disp_gamma.c b/drivers/gpu/drm/mediatek/mtk_disp_gamma.c
index 1e21dd92c88b..b9dc8754187d 100644
--- a/drivers/gpu/drm/mediatek/mtk_disp_gamma.c
+++ b/drivers/gpu/drm/mediatek/mtk_disp_gamma.c
@@ -66,11 +66,11 @@ void mtk_gamma_set_common(struct device *dev, void __iomem *regs,
 			  struct drm_crtc_state *state, u16 lut_size)
 {
 	struct mtk_disp_gamma *gamma;
-	unsigned int i, reg;
+	unsigned int i;
 	struct drm_color_lut *lut;
 	void __iomem *lut_base;
 	bool lut_diff;
-	u32 word;
+	u32 cfg_val, word;
 
 	/* If there's no gamma lut there's nothing to do here. */
 	if (!state->gamma_lut)
@@ -84,9 +84,7 @@ void mtk_gamma_set_common(struct device *dev, void __iomem *regs,
 	else
 		lut_diff = false;
 
-	reg = readl(regs + DISP_GAMMA_CFG);
-	reg = reg | GAMMA_LUT_EN;
-	writel(reg, regs + DISP_GAMMA_CFG);
+	cfg_val = readl(regs + DISP_GAMMA_CFG);
 	lut_base = regs + DISP_GAMMA_LUT;
 	lut = (struct drm_color_lut *)state->gamma_lut->data;
 	for (i = 0; i < lut_size; i++) {
@@ -116,6 +114,11 @@ void mtk_gamma_set_common(struct device *dev, void __iomem *regs,
 		}
 		writel(word, (lut_base + i * 4));
 	}
+
+	/* Enable the gamma table */
+	cfg_val = cfg_val | GAMMA_LUT_EN;
+
+	writel(cfg_val, regs + DISP_GAMMA_CFG);
 }
 
 void mtk_gamma_set(struct device *dev, struct drm_crtc_state *state)
-- 
2.41.0

[PATCH v8 06/13] drm/mediatek: gamma: Use bitfield macros

[AngeloGioacchino Del Regno]

Make the code more robust and improve readability by using bitfield
macros instead of open coding bit operations.
While at it, also add a definition for LUT_BITS_DEFAULT.

Signed-off-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Reviewed-by: Jason-JH.Lin <jason-jh.lin@mediatek.com>
Reviewed-by: Alexandre Mergnat <amergnat@baylibre.com>
---
 drivers/gpu/drm/mediatek/mtk_disp_gamma.c | 41 ++++++++++++++---------
 1 file changed, 26 insertions(+), 15 deletions(-)

diff --git a/drivers/gpu/drm/mediatek/mtk_disp_gamma.c b/drivers/gpu/drm/mediatek/mtk_disp_gamma.c
index b9dc8754187d..4f642fed432f 100644
--- a/drivers/gpu/drm/mediatek/mtk_disp_gamma.c
+++ b/drivers/gpu/drm/mediatek/mtk_disp_gamma.c
@@ -3,6 +3,7 @@
  * Copyright (c) 2021 MediaTek Inc.
  */
 
+#include <linux/bitfield.h>
 #include <linux/clk.h>
 #include <linux/component.h>
 #include <linux/module.h>
@@ -21,9 +22,16 @@
 #define GAMMA_LUT_EN					BIT(1)
 #define GAMMA_DITHERING					BIT(2)
 #define DISP_GAMMA_SIZE				0x0030
+#define DISP_GAMMA_SIZE_HSIZE				GENMASK(28, 16)
+#define DISP_GAMMA_SIZE_VSIZE				GENMASK(12, 0)
 #define DISP_GAMMA_LUT				0x0700
 
+#define DISP_GAMMA_LUT_10BIT_R			GENMASK(29, 20)
+#define DISP_GAMMA_LUT_10BIT_G			GENMASK(19, 10)
+#define DISP_GAMMA_LUT_10BIT_B			GENMASK(9, 0)
+
 #define LUT_10BIT_MASK				0x03ff
+#define LUT_BITS_DEFAULT			10
 
 struct mtk_disp_gamma_data {
 	bool has_dither;
@@ -90,33 +98,33 @@ void mtk_gamma_set_common(struct device *dev, void __iomem *regs,
 	for (i = 0; i < lut_size; i++) {
 		struct drm_color_lut diff, hwlut;
 
-		hwlut.red = drm_color_lut_extract(lut[i].red, 10);
-		hwlut.green = drm_color_lut_extract(lut[i].green, 10);
-		hwlut.blue = drm_color_lut_extract(lut[i].blue, 10);
+		hwlut.red = drm_color_lut_extract(lut[i].red, LUT_BITS_DEFAULT);
+		hwlut.green = drm_color_lut_extract(lut[i].green, LUT_BITS_DEFAULT);
+		hwlut.blue = drm_color_lut_extract(lut[i].blue, LUT_BITS_DEFAULT);
 
 		if (!lut_diff || (i % 2 == 0)) {
-			word = hwlut.red << 20 +
-			       hwlut.green << 10 +
-			       hwlut.red;
+			word = FIELD_PREP(DISP_GAMMA_LUT_10BIT_R, hwlut.red);
+			word |= FIELD_PREP(DISP_GAMMA_LUT_10BIT_G, hwlut.green);
+			word |= FIELD_PREP(DISP_GAMMA_LUT_10BIT_B, hwlut.blue);
 		} else {
 			diff.red = lut[i].red - lut[i - 1].red;
-			diff.red = drm_color_lut_extract(diff.red, 10);
+			diff.red = drm_color_lut_extract(diff.red, LUT_BITS_DEFAULT);
 
 			diff.green = lut[i].green - lut[i - 1].green;
-			diff.green = drm_color_lut_extract(diff.green, 10);
+			diff.green = drm_color_lut_extract(diff.green, LUT_BITS_DEFAULT);
 
 			diff.blue = lut[i].blue - lut[i - 1].blue;
-			diff.blue = drm_color_lut_extract(diff.blue, 10);
+			diff.blue = drm_color_lut_extract(diff.blue, LUT_BITS_DEFAULT);
 
-			word = diff.blue << 20 +
-			       diff.green << 10 +
-			       diff.red;
+			word = FIELD_PREP(DISP_GAMMA_LUT_10BIT_R, diff.red);
+			word |= FIELD_PREP(DISP_GAMMA_LUT_10BIT_G, diff.green);
+			word |= FIELD_PREP(DISP_GAMMA_LUT_10BIT_B, diff.blue);
 		}
 		writel(word, (lut_base + i * 4));
 	}
 
 	/* Enable the gamma table */
-	cfg_val = cfg_val | GAMMA_LUT_EN;
+	cfg_val |= FIELD_PREP(GAMMA_LUT_EN, 1);
 
 	writel(cfg_val, regs + DISP_GAMMA_CFG);
 }
@@ -133,9 +141,12 @@ void mtk_gamma_config(struct device *dev, unsigned int w,
 		      unsigned int bpc, struct cmdq_pkt *cmdq_pkt)
 {
 	struct mtk_disp_gamma *gamma = dev_get_drvdata(dev);
+	u32 sz;
+
+	sz = FIELD_PREP(DISP_GAMMA_SIZE_HSIZE, w);
+	sz |= FIELD_PREP(DISP_GAMMA_SIZE_VSIZE, h);
 
-	mtk_ddp_write(cmdq_pkt, h << 16 | w, &gamma->cmdq_reg, gamma->regs,
-		      DISP_GAMMA_SIZE);
+	mtk_ddp_write(cmdq_pkt, sz, &gamma->cmdq_reg, gamma->regs, DISP_GAMMA_SIZE);
 	if (gamma->data && gamma->data->has_dither)
 		mtk_dither_set_common(gamma->regs, &gamma->cmdq_reg, bpc,
 				      DISP_GAMMA_CFG, GAMMA_DITHERING, cmdq_pkt);
-- 
2.41.0

[PATCH v8 07/13] drm/mediatek: gamma: Support specifying number of bits per LUT component

[AngeloGioacchino Del Regno]

New SoCs, like MT8195, not only may support bigger lookup tables, but
have got a different register layout to support bigger precision:
support specifying the number of `lut_bits` for each SoC and use it
in mtk_gamma_set_common() to perform the right calculation.

Signed-off-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Reviewed-by: Jason-JH.Lin <jason-jh.lin@mediatek.com>
Reviewed-by: Alexandre Mergnat <amergnat@baylibre.com>
---
 drivers/gpu/drm/mediatek/mtk_disp_gamma.c | 23 +++++++++++++++--------
 1 file changed, 15 insertions(+), 8 deletions(-)

diff --git a/drivers/gpu/drm/mediatek/mtk_disp_gamma.c b/drivers/gpu/drm/mediatek/mtk_disp_gamma.c
index 4f642fed432f..a6f7af1a9e8e 100644
--- a/drivers/gpu/drm/mediatek/mtk_disp_gamma.c
+++ b/drivers/gpu/drm/mediatek/mtk_disp_gamma.c
@@ -37,6 +37,7 @@ struct mtk_disp_gamma_data {
 	bool has_dither;
 	bool lut_diff;
 	u16 lut_size;
+	u8 lut_bits;
 };
 
 /*
@@ -78,6 +79,7 @@ void mtk_gamma_set_common(struct device *dev, void __iomem *regs,
 	struct drm_color_lut *lut;
 	void __iomem *lut_base;
 	bool lut_diff;
+	u8 lut_bits;
 	u32 cfg_val, word;
 
 	/* If there's no gamma lut there's nothing to do here. */
@@ -87,10 +89,13 @@ void mtk_gamma_set_common(struct device *dev, void __iomem *regs,
 	/* 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_bits = gamma->data->lut_bits;
+	} else {
 		lut_diff = false;
+		lut_bits = LUT_BITS_DEFAULT;
+	}
 
 	cfg_val = readl(regs + DISP_GAMMA_CFG);
 	lut_base = regs + DISP_GAMMA_LUT;
@@ -98,9 +103,9 @@ void mtk_gamma_set_common(struct device *dev, void __iomem *regs,
 	for (i = 0; i < lut_size; i++) {
 		struct drm_color_lut diff, hwlut;
 
-		hwlut.red = drm_color_lut_extract(lut[i].red, LUT_BITS_DEFAULT);
-		hwlut.green = drm_color_lut_extract(lut[i].green, LUT_BITS_DEFAULT);
-		hwlut.blue = drm_color_lut_extract(lut[i].blue, LUT_BITS_DEFAULT);
+		hwlut.red = drm_color_lut_extract(lut[i].red, lut_bits);
+		hwlut.green = drm_color_lut_extract(lut[i].green, lut_bits);
+		hwlut.blue = drm_color_lut_extract(lut[i].blue, lut_bits);
 
 		if (!lut_diff || (i % 2 == 0)) {
 			word = FIELD_PREP(DISP_GAMMA_LUT_10BIT_R, hwlut.red);
@@ -108,13 +113,13 @@ void mtk_gamma_set_common(struct device *dev, void __iomem *regs,
 			word |= FIELD_PREP(DISP_GAMMA_LUT_10BIT_B, hwlut.blue);
 		} else {
 			diff.red = lut[i].red - lut[i - 1].red;
-			diff.red = drm_color_lut_extract(diff.red, LUT_BITS_DEFAULT);
+			diff.red = drm_color_lut_extract(diff.red, lut_bits);
 
 			diff.green = lut[i].green - lut[i - 1].green;
-			diff.green = drm_color_lut_extract(diff.green, LUT_BITS_DEFAULT);
+			diff.green = drm_color_lut_extract(diff.green, lut_bits);
 
 			diff.blue = lut[i].blue - lut[i - 1].blue;
-			diff.blue = drm_color_lut_extract(diff.blue, LUT_BITS_DEFAULT);
+			diff.blue = drm_color_lut_extract(diff.blue, lut_bits);
 
 			word = FIELD_PREP(DISP_GAMMA_LUT_10BIT_R, diff.red);
 			word |= FIELD_PREP(DISP_GAMMA_LUT_10BIT_G, diff.green);
@@ -231,10 +236,12 @@ static int mtk_disp_gamma_remove(struct platform_device *pdev)
 
 static const struct mtk_disp_gamma_data mt8173_gamma_driver_data = {
 	.has_dither = true,
+	.lut_bits = 10,
 	.lut_size = 512,
 };
 
 static const struct mtk_disp_gamma_data mt8183_gamma_driver_data = {
+	.lut_bits = 10,
 	.lut_diff = true,
 	.lut_size = 512,
 };
-- 
2.41.0

[PATCH v8 08/13] drm/mediatek: gamma: Support multi-bank gamma LUT

[AngeloGioacchino Del Regno]

Newer Gamma IP have got multiple LUT banks: support specifying the
size of the LUT banks and handle bank-switching before programming
the LUT in mtk_gamma_set_common() in preparation for adding support
for MT8195 and newer SoCs.

Suggested-by: Jason-JH.Lin <jason-jh.lin@mediatek.com>
[Angelo: Refactored original commit]
Signed-off-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Reviewed-by: Alexandre Mergnat <amergnat@baylibre.com>
---
 drivers/gpu/drm/mediatek/mtk_disp_gamma.c | 73 +++++++++++++++--------
 1 file changed, 47 insertions(+), 26 deletions(-)

diff --git a/drivers/gpu/drm/mediatek/mtk_disp_gamma.c b/drivers/gpu/drm/mediatek/mtk_disp_gamma.c
index a6f7af1a9e8e..fb7c3650a9f7 100644
--- a/drivers/gpu/drm/mediatek/mtk_disp_gamma.c
+++ b/drivers/gpu/drm/mediatek/mtk_disp_gamma.c
@@ -24,6 +24,8 @@
 #define DISP_GAMMA_SIZE				0x0030
 #define DISP_GAMMA_SIZE_HSIZE				GENMASK(28, 16)
 #define DISP_GAMMA_SIZE_VSIZE				GENMASK(12, 0)
+#define DISP_GAMMA_BANK				0x0100
+#define DISP_GAMMA_BANK_BANK				GENMASK(1, 0)
 #define DISP_GAMMA_LUT				0x0700
 
 #define DISP_GAMMA_LUT_10BIT_R			GENMASK(29, 20)
@@ -32,10 +34,12 @@
 
 #define LUT_10BIT_MASK				0x03ff
 #define LUT_BITS_DEFAULT			10
+#define LUT_BANK_SIZE_DEFAULT			512
 
 struct mtk_disp_gamma_data {
 	bool has_dither;
 	bool lut_diff;
+	u16 lut_bank_size;
 	u16 lut_size;
 	u8 lut_bits;
 };
@@ -80,7 +84,9 @@ void mtk_gamma_set_common(struct device *dev, void __iomem *regs,
 	void __iomem *lut_base;
 	bool lut_diff;
 	u8 lut_bits;
-	u32 cfg_val, word;
+	u16 lut_bank_size;
+	u32 cfg_val, lbank_val, word;
+	int cur_bank, num_lut_banks;
 
 	/* If there's no gamma lut there's nothing to do here. */
 	if (!state->gamma_lut)
@@ -91,41 +97,54 @@ void mtk_gamma_set_common(struct device *dev, void __iomem *regs,
 
 	if (gamma && gamma->data) {
 		lut_diff = gamma->data->lut_diff;
+		lut_bank_size = gamma->data->lut_bank_size;
 		lut_bits = gamma->data->lut_bits;
 	} else {
 		lut_diff = false;
+		lut_bank_size = LUT_BANK_SIZE_DEFAULT;
 		lut_bits = LUT_BITS_DEFAULT;
 	}
+	num_lut_banks = lut_size / lut_bank_size;
 
 	cfg_val = readl(regs + DISP_GAMMA_CFG);
 	lut_base = regs + DISP_GAMMA_LUT;
 	lut = (struct drm_color_lut *)state->gamma_lut->data;
-	for (i = 0; i < lut_size; i++) {
-		struct drm_color_lut diff, hwlut;
-
-		hwlut.red = drm_color_lut_extract(lut[i].red, lut_bits);
-		hwlut.green = drm_color_lut_extract(lut[i].green, lut_bits);
-		hwlut.blue = drm_color_lut_extract(lut[i].blue, lut_bits);
-
-		if (!lut_diff || (i % 2 == 0)) {
-			word = FIELD_PREP(DISP_GAMMA_LUT_10BIT_R, hwlut.red);
-			word |= FIELD_PREP(DISP_GAMMA_LUT_10BIT_G, hwlut.green);
-			word |= FIELD_PREP(DISP_GAMMA_LUT_10BIT_B, hwlut.blue);
-		} else {
-			diff.red = lut[i].red - lut[i - 1].red;
-			diff.red = drm_color_lut_extract(diff.red, lut_bits);
-
-			diff.green = lut[i].green - lut[i - 1].green;
-			diff.green = drm_color_lut_extract(diff.green, lut_bits);
-
-			diff.blue = lut[i].blue - lut[i - 1].blue;
-			diff.blue = drm_color_lut_extract(diff.blue, lut_bits);
-
-			word = FIELD_PREP(DISP_GAMMA_LUT_10BIT_R, diff.red);
-			word |= FIELD_PREP(DISP_GAMMA_LUT_10BIT_G, diff.green);
-			word |= FIELD_PREP(DISP_GAMMA_LUT_10BIT_B, diff.blue);
+	for (cur_bank = 0; cur_bank < num_lut_banks; cur_bank++) {
+
+		/* Switch gamma bank and set data mode before writing LUT */
+		if (num_lut_banks > 1) {
+			lbank_val = FIELD_PREP(DISP_GAMMA_BANK_BANK, cur_bank);
+			writel(lbank_val, regs + DISP_GAMMA_BANK);
+		}
+
+		for (i = 0; i < lut_bank_size; i++) {
+			int n = (cur_bank * lut_bank_size) + i;
+			struct drm_color_lut diff, hwlut;
+
+			hwlut.red = drm_color_lut_extract(lut[n].red, lut_bits);
+			hwlut.green = drm_color_lut_extract(lut[n].green, lut_bits);
+			hwlut.blue = drm_color_lut_extract(lut[n].blue, lut_bits);
+
+			if (!lut_diff || (i % 2 == 0)) {
+				word = FIELD_PREP(DISP_GAMMA_LUT_10BIT_R, hwlut.red);
+				word |= FIELD_PREP(DISP_GAMMA_LUT_10BIT_G, hwlut.green);
+				word |= FIELD_PREP(DISP_GAMMA_LUT_10BIT_B, hwlut.blue);
+			} else {
+				diff.red = lut[n].red - lut[n - 1].red;
+				diff.red = drm_color_lut_extract(diff.red, lut_bits);
+
+				diff.green = lut[n].green - lut[n - 1].green;
+				diff.green = drm_color_lut_extract(diff.green, lut_bits);
+
+				diff.blue = lut[n].blue - lut[n - 1].blue;
+				diff.blue = drm_color_lut_extract(diff.blue, lut_bits);
+
+				word = FIELD_PREP(DISP_GAMMA_LUT_10BIT_R, diff.red);
+				word |= FIELD_PREP(DISP_GAMMA_LUT_10BIT_G, diff.green);
+				word |= FIELD_PREP(DISP_GAMMA_LUT_10BIT_B, diff.blue);
+			}
+			writel(word, (lut_base + i * 4));
 		}
-		writel(word, (lut_base + i * 4));
 	}
 
 	/* Enable the gamma table */
@@ -236,11 +255,13 @@ static int mtk_disp_gamma_remove(struct platform_device *pdev)
 
 static const struct mtk_disp_gamma_data mt8173_gamma_driver_data = {
 	.has_dither = true,
+	.lut_bank_size = 512,
 	.lut_bits = 10,
 	.lut_size = 512,
 };
 
 static const struct mtk_disp_gamma_data mt8183_gamma_driver_data = {
+	.lut_bank_size = 512,
 	.lut_bits = 10,
 	.lut_diff = true,
 	.lut_size = 512,
-- 
2.41.0

[PATCH v8 09/13] drm/mediatek: gamma: Add support for 12-bit LUT and MT8195

[AngeloGioacchino Del Regno]

Add support for 12-bit gamma lookup tables and introduce the first
user for it: MT8195.
While at it, also reorder the variables in mtk_gamma_set_common()
and rename `lut_base` to `lut0_base` to improve readability.

Signed-off-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Reviewed-by: Jason-JH.Lin <jason-jh.lin@mediatek.com>
Reviewed-by: Alexandre Mergnat <amergnat@baylibre.com>
---
 drivers/gpu/drm/mediatek/mtk_disp_gamma.c | 77 +++++++++++++++++++----
 1 file changed, 64 insertions(+), 13 deletions(-)

diff --git a/drivers/gpu/drm/mediatek/mtk_disp_gamma.c b/drivers/gpu/drm/mediatek/mtk_disp_gamma.c
index fb7c3650a9f7..12614cc26bf8 100644
--- a/drivers/gpu/drm/mediatek/mtk_disp_gamma.c
+++ b/drivers/gpu/drm/mediatek/mtk_disp_gamma.c
@@ -26,12 +26,20 @@
 #define DISP_GAMMA_SIZE_VSIZE				GENMASK(12, 0)
 #define DISP_GAMMA_BANK				0x0100
 #define DISP_GAMMA_BANK_BANK				GENMASK(1, 0)
+#define DISP_GAMMA_BANK_DATA_MODE			BIT(2)
 #define DISP_GAMMA_LUT				0x0700
+#define DISP_GAMMA_LUT1				0x0b00
 
+/* For 10 bit LUT layout, R/G/B are in the same register */
 #define DISP_GAMMA_LUT_10BIT_R			GENMASK(29, 20)
 #define DISP_GAMMA_LUT_10BIT_G			GENMASK(19, 10)
 #define DISP_GAMMA_LUT_10BIT_B			GENMASK(9, 0)
 
+/* For 12 bit LUT layout, R/G are in LUT, B is in LUT1 */
+#define DISP_GAMMA_LUT_12BIT_R			GENMASK(11, 0)
+#define DISP_GAMMA_LUT_12BIT_G			GENMASK(23, 12)
+#define DISP_GAMMA_LUT_12BIT_B			GENMASK(11, 0)
+
 #define LUT_10BIT_MASK				0x03ff
 #define LUT_BITS_DEFAULT			10
 #define LUT_BANK_SIZE_DEFAULT			512
@@ -75,18 +83,34 @@ unsigned int mtk_gamma_get_lut_size(struct device *dev)
 	return gamma->data->lut_size;
 }
 
+/*
+ * SoCs supporting 12-bits LUTs are using a new register layout that does
+ * always support (by HW) both 12-bits and 10-bits LUT but, on those, we
+ * ignore the support for 10-bits in this driver and always use 12-bits.
+ *
+ * Summarizing:
+ * - SoC HW support 9/10-bits LUT only
+ *   - Old register layout
+ *     - 10-bits LUT supported
+ *     - 9-bits LUT not supported
+ * - SoC HW support both 10/12bits LUT
+ *   - New register layout
+ *     - 12-bits LUT supported
+ *     - 10-its LUT not supported
+ */
 void mtk_gamma_set_common(struct device *dev, void __iomem *regs,
 			  struct drm_crtc_state *state, u16 lut_size)
 {
 	struct mtk_disp_gamma *gamma;
-	unsigned int i;
+	void __iomem *lut0_base = regs + DISP_GAMMA_LUT;
+	void __iomem *lut1_base = regs + DISP_GAMMA_LUT1;
+	u32 cfg_val, data_mode, lbank_val, word[2];
+	int cur_bank, num_lut_banks;
 	struct drm_color_lut *lut;
-	void __iomem *lut_base;
+	u16 lut_bank_size;
+	unsigned int i;
 	bool lut_diff;
 	u8 lut_bits;
-	u16 lut_bank_size;
-	u32 cfg_val, lbank_val, word;
-	int cur_bank, num_lut_banks;
 
 	/* If there's no gamma lut there's nothing to do here. */
 	if (!state->gamma_lut)
@@ -107,13 +131,17 @@ void mtk_gamma_set_common(struct device *dev, void __iomem *regs,
 	num_lut_banks = lut_size / lut_bank_size;
 
 	cfg_val = readl(regs + DISP_GAMMA_CFG);
-	lut_base = regs + DISP_GAMMA_LUT;
 	lut = (struct drm_color_lut *)state->gamma_lut->data;
+
+	/* Switch to 12 bits data mode if supported */
+	data_mode = FIELD_PREP(DISP_GAMMA_BANK_DATA_MODE, !!(lut_bits == 12));
+
 	for (cur_bank = 0; cur_bank < num_lut_banks; cur_bank++) {
 
 		/* Switch gamma bank and set data mode before writing LUT */
 		if (num_lut_banks > 1) {
 			lbank_val = FIELD_PREP(DISP_GAMMA_BANK_BANK, cur_bank);
+			lbank_val |= data_mode;
 			writel(lbank_val, regs + DISP_GAMMA_BANK);
 		}
 
@@ -126,9 +154,15 @@ void mtk_gamma_set_common(struct device *dev, void __iomem *regs,
 			hwlut.blue = drm_color_lut_extract(lut[n].blue, lut_bits);
 
 			if (!lut_diff || (i % 2 == 0)) {
-				word = FIELD_PREP(DISP_GAMMA_LUT_10BIT_R, hwlut.red);
-				word |= FIELD_PREP(DISP_GAMMA_LUT_10BIT_G, hwlut.green);
-				word |= FIELD_PREP(DISP_GAMMA_LUT_10BIT_B, hwlut.blue);
+				if (lut_bits == 12) {
+					word[0] = FIELD_PREP(DISP_GAMMA_LUT_12BIT_R, hwlut.red);
+					word[0] |= FIELD_PREP(DISP_GAMMA_LUT_12BIT_G, hwlut.green);
+					word[1] = FIELD_PREP(DISP_GAMMA_LUT_12BIT_B, hwlut.blue);
+				} else {
+					word[0] = FIELD_PREP(DISP_GAMMA_LUT_10BIT_R, hwlut.red);
+					word[0] |= FIELD_PREP(DISP_GAMMA_LUT_10BIT_G, hwlut.green);
+					word[0] |= FIELD_PREP(DISP_GAMMA_LUT_10BIT_B, hwlut.blue);
+				}
 			} else {
 				diff.red = lut[n].red - lut[n - 1].red;
 				diff.red = drm_color_lut_extract(diff.red, lut_bits);
@@ -139,11 +173,19 @@ void mtk_gamma_set_common(struct device *dev, void __iomem *regs,
 				diff.blue = lut[n].blue - lut[n - 1].blue;
 				diff.blue = drm_color_lut_extract(diff.blue, lut_bits);
 
-				word = FIELD_PREP(DISP_GAMMA_LUT_10BIT_R, diff.red);
-				word |= FIELD_PREP(DISP_GAMMA_LUT_10BIT_G, diff.green);
-				word |= FIELD_PREP(DISP_GAMMA_LUT_10BIT_B, diff.blue);
+				if (lut_bits == 12) {
+					word[0] = FIELD_PREP(DISP_GAMMA_LUT_12BIT_R, diff.red);
+					word[0] |= FIELD_PREP(DISP_GAMMA_LUT_12BIT_G, diff.green);
+					word[1] = FIELD_PREP(DISP_GAMMA_LUT_12BIT_B, diff.blue);
+				} else {
+					word[0] = FIELD_PREP(DISP_GAMMA_LUT_10BIT_R, diff.red);
+					word[0] |= FIELD_PREP(DISP_GAMMA_LUT_10BIT_G, diff.green);
+					word[0] |= FIELD_PREP(DISP_GAMMA_LUT_10BIT_B, diff.blue);
+				}
 			}
-			writel(word, (lut_base + i * 4));
+			writel(word[0], (lut0_base + i * 4));
+			if (lut_bits == 12)
+				writel(word[1], (lut1_base + i * 4));
 		}
 	}
 
@@ -267,11 +309,20 @@ static const struct mtk_disp_gamma_data mt8183_gamma_driver_data = {
 	.lut_size = 512,
 };
 
+static const struct mtk_disp_gamma_data mt8195_gamma_driver_data = {
+	.lut_bank_size = 256,
+	.lut_bits = 12,
+	.lut_diff = true,
+	.lut_size = 1024,
+};
+
 static const struct of_device_id mtk_disp_gamma_driver_dt_match[] = {
 	{ .compatible = "mediatek,mt8173-disp-gamma",
 	  .data = &mt8173_gamma_driver_data},
 	{ .compatible = "mediatek,mt8183-disp-gamma",
 	  .data = &mt8183_gamma_driver_data},
+	{ .compatible = "mediatek,mt8195-disp-gamma",
+	  .data = &mt8195_gamma_driver_data},
 	{},
 };
 MODULE_DEVICE_TABLE(of, mtk_disp_gamma_driver_dt_match);
-- 
2.41.0

[PATCH v8 10/13] drm/mediatek: gamma: Make sure relay mode is disabled

[AngeloGioacchino Del Regno]

Disable relay mode at the end of LUT programming to make sure that the
processed image goes through.

Signed-off-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Reviewed-by: Jason-JH.Lin <jason-jh.lin@mediatek.com>
Reviewed-by: Alexandre Mergnat <amergnat@baylibre.com>
---
 drivers/gpu/drm/mediatek/mtk_disp_gamma.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/drivers/gpu/drm/mediatek/mtk_disp_gamma.c b/drivers/gpu/drm/mediatek/mtk_disp_gamma.c
index 12614cc26bf8..6591797ed10c 100644
--- a/drivers/gpu/drm/mediatek/mtk_disp_gamma.c
+++ b/drivers/gpu/drm/mediatek/mtk_disp_gamma.c
@@ -19,6 +19,7 @@
 #define DISP_GAMMA_EN				0x0000
 #define GAMMA_EN					BIT(0)
 #define DISP_GAMMA_CFG				0x0020
+#define GAMMA_RELAY_MODE				BIT(0)
 #define GAMMA_LUT_EN					BIT(1)
 #define GAMMA_DITHERING					BIT(2)
 #define DISP_GAMMA_SIZE				0x0030
@@ -192,6 +193,9 @@ void mtk_gamma_set_common(struct device *dev, void __iomem *regs,
 	/* Enable the gamma table */
 	cfg_val |= FIELD_PREP(GAMMA_LUT_EN, 1);
 
+	/* Disable RELAY mode to pass the processed image */
+	cfg_val &= ~GAMMA_RELAY_MODE;
+
 	writel(cfg_val, regs + DISP_GAMMA_CFG);
 }
 
-- 
2.41.0

[PATCH v8 11/13] drm/mediatek: gamma: Program gamma LUT type for descending or rising

[AngeloGioacchino Del Regno]

All of the SoCs that don't have dithering control in the gamma IP
have got a GAMMA_LUT_TYPE bit that tells to the IP if the LUT is
"descending" (bit set) or "rising" (bit cleared): make sure to set
it correctly after programming the LUT.

Signed-off-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Reviewed-by: Jason-JH.Lin <jason-jh.lin@mediatek.com>
Reviewed-by: Alexandre Mergnat <amergnat@baylibre.com>
---
 drivers/gpu/drm/mediatek/mtk_disp_gamma.c | 19 +++++++++++++++++++
 1 file changed, 19 insertions(+)

diff --git a/drivers/gpu/drm/mediatek/mtk_disp_gamma.c b/drivers/gpu/drm/mediatek/mtk_disp_gamma.c
index 6591797ed10c..c6b77ca3e655 100644
--- a/drivers/gpu/drm/mediatek/mtk_disp_gamma.c
+++ b/drivers/gpu/drm/mediatek/mtk_disp_gamma.c
@@ -22,6 +22,7 @@
 #define GAMMA_RELAY_MODE				BIT(0)
 #define GAMMA_LUT_EN					BIT(1)
 #define GAMMA_DITHERING					BIT(2)
+#define GAMMA_LUT_TYPE					BIT(2)
 #define DISP_GAMMA_SIZE				0x0030
 #define DISP_GAMMA_SIZE_HSIZE				GENMASK(28, 16)
 #define DISP_GAMMA_SIZE_VSIZE				GENMASK(12, 0)
@@ -84,6 +85,16 @@ unsigned int mtk_gamma_get_lut_size(struct device *dev)
 	return gamma->data->lut_size;
 }
 
+static bool mtk_gamma_lut_is_descending(struct drm_color_lut *lut, u32 lut_size)
+{
+	u64 first, last;
+
+	first = lut[0].red + lut[0].green + lut[0].blue;
+	last = lut[lut_size].red + lut[lut_size].green + lut[lut_size].blue;
+
+	return !!(first > last);
+}
+
 /*
  * SoCs supporting 12-bits LUTs are using a new register layout that does
  * always support (by HW) both 12-bits and 10-bits LUT but, on those, we
@@ -190,6 +201,14 @@ void mtk_gamma_set_common(struct device *dev, void __iomem *regs,
 		}
 	}
 
+	if (gamma && gamma->data && !gamma->data->has_dither) {
+		/* Descending or Rising LUT */
+		if (mtk_gamma_lut_is_descending(lut, lut_size))
+			cfg_val |= FIELD_PREP(GAMMA_LUT_TYPE, 1);
+		else
+			cfg_val &= ~GAMMA_LUT_TYPE;
+	}
+
 	/* Enable the gamma table */
 	cfg_val |= FIELD_PREP(GAMMA_LUT_EN, 1);
 
-- 
2.41.0

[PATCH v8 12/13] drm/mediatek: mtk_disp_aal: Rewrite kerneldoc for struct mtk_disp_aal

[AngeloGioacchino Del Regno]

The kerneldoc for struct mtk_disp_aal was entirely wrong: rewrite it
to actually document the structure.

Signed-off-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
---
 drivers/gpu/drm/mediatek/mtk_disp_aal.c | 8 +++++---
 1 file changed, 5 insertions(+), 3 deletions(-)

diff --git a/drivers/gpu/drm/mediatek/mtk_disp_aal.c b/drivers/gpu/drm/mediatek/mtk_disp_aal.c
index e390ccfdee18..d93b97a84825 100644
--- a/drivers/gpu/drm/mediatek/mtk_disp_aal.c
+++ b/drivers/gpu/drm/mediatek/mtk_disp_aal.c
@@ -26,9 +26,11 @@ struct mtk_disp_aal_data {
 };
 
 /**
- * struct mtk_disp_aal - DISP_AAL driver structure
- * @ddp_comp - structure containing type enum and hardware resources
- * @crtc - associated crtc to report irq events to
+ * struct mtk_disp_aal - Display Adaptive Ambient Light driver structure
+ * @clk:      clock for DISP_AAL controller
+ * @regs:     MMIO registers base
+ * @cmdq_reg: CMDQ Client register
+ * @data:     platform specific data for DISP_AAL
  */
 struct mtk_disp_aal {
 	struct clk *clk;
-- 
2.41.0

[PATCH v8 13/13] drm/mediatek: mtk_disp_gamma: Add kerneldoc for struct mtk_disp_gamma

[AngeloGioacchino Del Regno]

The mtk_disp_gamma structure was completely undocumented: add some
kerneldoc documentation to it.

Signed-off-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
---
 drivers/gpu/drm/mediatek/mtk_disp_gamma.c | 8 ++++++--
 1 file changed, 6 insertions(+), 2 deletions(-)

diff --git a/drivers/gpu/drm/mediatek/mtk_disp_gamma.c b/drivers/gpu/drm/mediatek/mtk_disp_gamma.c
index c6b77ca3e655..9be1efa9766c 100644
--- a/drivers/gpu/drm/mediatek/mtk_disp_gamma.c
+++ b/drivers/gpu/drm/mediatek/mtk_disp_gamma.c
@@ -54,8 +54,12 @@ struct mtk_disp_gamma_data {
 	u8 lut_bits;
 };
 
-/*
- * struct mtk_disp_gamma - DISP_GAMMA driver structure
+/**
+ * struct mtk_disp_gamma - Display Gamma driver structure
+ * @clk:      clock for DISP_GAMMA block
+ * @regs:     MMIO registers base
+ * @cmdq_reg: CMDQ Client register
+ * @data:     platform data for DISP_GAMMA
  */
 struct mtk_disp_gamma {
 	struct clk *clk;
-- 
2.41.0

Re: [PATCH v8 07/13] drm/mediatek: gamma: Support specifying number of bits per LUT component

[CK Hu (胡俊光)]

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[-- Attachment #2: Type: text/plain, Size: 4042 bytes --]

Hi, Angelo:

On Tue, 2023-08-01 at 13:58 +0200, AngeloGioacchino Del Regno wrote:
> New SoCs, like MT8195, not only may support bigger lookup tables, but
> have got a different register layout to support bigger precision:
> support specifying the number of `lut_bits` for each SoC and use it
> in mtk_gamma_set_common() to perform the right calculation.
> 
> Signed-off-by: AngeloGioacchino Del Regno <
> angelogioacchino.delregno@collabora.com>
> Reviewed-by: Jason-JH.Lin <jason-jh.lin@mediatek.com>
> Reviewed-by: Alexandre Mergnat <amergnat@baylibre.com>
> ---
>  drivers/gpu/drm/mediatek/mtk_disp_gamma.c | 23 +++++++++++++++----
> ----
>  1 file changed, 15 insertions(+), 8 deletions(-)
> 
> diff --git a/drivers/gpu/drm/mediatek/mtk_disp_gamma.c
> b/drivers/gpu/drm/mediatek/mtk_disp_gamma.c
> index 4f642fed432f..a6f7af1a9e8e 100644
> --- a/drivers/gpu/drm/mediatek/mtk_disp_gamma.c
> +++ b/drivers/gpu/drm/mediatek/mtk_disp_gamma.c
> @@ -37,6 +37,7 @@ struct mtk_disp_gamma_data {
>  	bool has_dither;
>  	bool lut_diff;
>  	u16 lut_size;
> +	u8 lut_bits;
>  };
>  
>  /*
> @@ -78,6 +79,7 @@ void mtk_gamma_set_common(struct device *dev, void
> __iomem *regs,
>  	struct drm_color_lut *lut;
>  	void __iomem *lut_base;
>  	bool lut_diff;
> +	u8 lut_bits;
>  	u32 cfg_val, word;
>  
>  	/* If there's no gamma lut there's nothing to do here. */
> @@ -87,10 +89,13 @@ void mtk_gamma_set_common(struct device *dev,
> void __iomem *regs,
>  	/* 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_bits = gamma->data->lut_bits;
> +	} else {
>  		lut_diff = false;
> +		lut_bits = LUT_BITS_DEFAULT;

LUT_BITS_DEFAULT is only for AAL driver, so place this definition in
AAL driver and pass it into this function.

Regards,
CK

> +	}
>  
>  	cfg_val = readl(regs + DISP_GAMMA_CFG);
>  	lut_base = regs + DISP_GAMMA_LUT;
> @@ -98,9 +103,9 @@ void mtk_gamma_set_common(struct device *dev, void
> __iomem *regs,
>  	for (i = 0; i < lut_size; i++) {
>  		struct drm_color_lut diff, hwlut;
>  
> -		hwlut.red = drm_color_lut_extract(lut[i].red,
> LUT_BITS_DEFAULT);
> -		hwlut.green = drm_color_lut_extract(lut[i].green,
> LUT_BITS_DEFAULT);
> -		hwlut.blue = drm_color_lut_extract(lut[i].blue,
> LUT_BITS_DEFAULT);
> +		hwlut.red = drm_color_lut_extract(lut[i].red,
> lut_bits);
> +		hwlut.green = drm_color_lut_extract(lut[i].green,
> lut_bits);
> +		hwlut.blue = drm_color_lut_extract(lut[i].blue,
> lut_bits);
>  
>  		if (!lut_diff || (i % 2 == 0)) {
>  			word = FIELD_PREP(DISP_GAMMA_LUT_10BIT_R,
> hwlut.red);
> @@ -108,13 +113,13 @@ void mtk_gamma_set_common(struct device *dev,
> void __iomem *regs,
>  			word |= FIELD_PREP(DISP_GAMMA_LUT_10BIT_B,
> hwlut.blue);
>  		} else {
>  			diff.red = lut[i].red - lut[i - 1].red;
> -			diff.red = drm_color_lut_extract(diff.red,
> LUT_BITS_DEFAULT);
> +			diff.red = drm_color_lut_extract(diff.red,
> lut_bits);
>  
>  			diff.green = lut[i].green - lut[i - 1].green;
> -			diff.green = drm_color_lut_extract(diff.green,
> LUT_BITS_DEFAULT);
> +			diff.green = drm_color_lut_extract(diff.green,
> lut_bits);
>  
>  			diff.blue = lut[i].blue - lut[i - 1].blue;
> -			diff.blue = drm_color_lut_extract(diff.blue,
> LUT_BITS_DEFAULT);
> +			diff.blue = drm_color_lut_extract(diff.blue,
> lut_bits);
>  
>  			word = FIELD_PREP(DISP_GAMMA_LUT_10BIT_R,
> diff.red);
>  			word |= FIELD_PREP(DISP_GAMMA_LUT_10BIT_G,
> diff.green);
> @@ -231,10 +236,12 @@ static int mtk_disp_gamma_remove(struct
> platform_device *pdev)
>  
>  static const struct mtk_disp_gamma_data mt8173_gamma_driver_data = {
>  	.has_dither = true,
> +	.lut_bits = 10,
>  	.lut_size = 512,
>  };
>  
>  static const struct mtk_disp_gamma_data mt8183_gamma_driver_data = {
> +	.lut_bits = 10,
>  	.lut_diff = true,
>  	.lut_size = 512,
>  };

Re: [PATCH v8 08/13] drm/mediatek: gamma: Support multi-bank gamma LUT

[CK Hu (胡俊光)]

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Hi, Angelo:

On Tue, 2023-08-01 at 13:58 +0200, AngeloGioacchino Del Regno wrote:
> Newer Gamma IP have got multiple LUT banks: support specifying the
> size of the LUT banks and handle bank-switching before programming
> the LUT in mtk_gamma_set_common() in preparation for adding support
> for MT8195 and newer SoCs.
> 
> Suggested-by: Jason-JH.Lin <jason-jh.lin@mediatek.com>
> [Angelo: Refactored original commit]
> Signed-off-by: AngeloGioacchino Del Regno <
> angelogioacchino.delregno@collabora.com>
> Reviewed-by: Alexandre Mergnat <amergnat@baylibre.com>
> ---
>  drivers/gpu/drm/mediatek/mtk_disp_gamma.c | 73 +++++++++++++++----
> ----
>  1 file changed, 47 insertions(+), 26 deletions(-)
> 
> diff --git a/drivers/gpu/drm/mediatek/mtk_disp_gamma.c
> b/drivers/gpu/drm/mediatek/mtk_disp_gamma.c
> index a6f7af1a9e8e..fb7c3650a9f7 100644
> --- a/drivers/gpu/drm/mediatek/mtk_disp_gamma.c
> +++ b/drivers/gpu/drm/mediatek/mtk_disp_gamma.c
> @@ -24,6 +24,8 @@
>  #define DISP_GAMMA_SIZE				0x0030
>  #define DISP_GAMMA_SIZE_HSIZE				GENMASK
> (28, 16)
>  #define DISP_GAMMA_SIZE_VSIZE				GENMASK
> (12, 0)
> +#define DISP_GAMMA_BANK				0x0100
> +#define DISP_GAMMA_BANK_BANK				GENMASK(1, 0)
>  #define DISP_GAMMA_LUT				0x0700
>  
>  #define DISP_GAMMA_LUT_10BIT_R			GENMASK(29, 20)
> @@ -32,10 +34,12 @@
>  
>  #define LUT_10BIT_MASK				0x03ff
>  #define LUT_BITS_DEFAULT			10
> +#define LUT_BANK_SIZE_DEFAULT			512
>  
>  struct mtk_disp_gamma_data {
>  	bool has_dither;
>  	bool lut_diff;
> +	u16 lut_bank_size;
>  	u16 lut_size;
>  	u8 lut_bits;
>  };
> @@ -80,7 +84,9 @@ void mtk_gamma_set_common(struct device *dev, void
> __iomem *regs,
>  	void __iomem *lut_base;
>  	bool lut_diff;
>  	u8 lut_bits;
> -	u32 cfg_val, word;
> +	u16 lut_bank_size;
> +	u32 cfg_val, lbank_val, word;
> +	int cur_bank, num_lut_banks;
>  
>  	/* If there's no gamma lut there's nothing to do here. */
>  	if (!state->gamma_lut)
> @@ -91,41 +97,54 @@ void mtk_gamma_set_common(struct device *dev,
> void __iomem *regs,
>  
>  	if (gamma && gamma->data) {
>  		lut_diff = gamma->data->lut_diff;
> +		lut_bank_size = gamma->data->lut_bank_size;
>  		lut_bits = gamma->data->lut_bits;
>  	} else {
>  		lut_diff = false;
> +		lut_bank_size = LUT_BANK_SIZE_DEFAULT;

LUT_BANK_SIZE_DEFAULT is only for AAL driver, so place it in AAL driver
and pass it into this function.

Regards,
CK

>  		lut_bits = LUT_BITS_DEFAULT;
>  	}
> +	num_lut_banks = lut_size / lut_bank_size;
>  
>  	cfg_val = readl(regs + DISP_GAMMA_CFG);
>  	lut_base = regs + DISP_GAMMA_LUT;
>  	lut = (struct drm_color_lut *)state->gamma_lut->data;
> -	for (i = 0; i < lut_size; i++) {
> -		struct drm_color_lut diff, hwlut;
> -
> -		hwlut.red = drm_color_lut_extract(lut[i].red,
> lut_bits);
> -		hwlut.green = drm_color_lut_extract(lut[i].green,
> lut_bits);
> -		hwlut.blue = drm_color_lut_extract(lut[i].blue,
> lut_bits);
> -
> -		if (!lut_diff || (i % 2 == 0)) {
> -			word = FIELD_PREP(DISP_GAMMA_LUT_10BIT_R,
> hwlut.red);
> -			word |= FIELD_PREP(DISP_GAMMA_LUT_10BIT_G,
> hwlut.green);
> -			word |= FIELD_PREP(DISP_GAMMA_LUT_10BIT_B,
> hwlut.blue);
> -		} else {
> -			diff.red = lut[i].red - lut[i - 1].red;
> -			diff.red = drm_color_lut_extract(diff.red,
> lut_bits);
> -
> -			diff.green = lut[i].green - lut[i - 1].green;
> -			diff.green = drm_color_lut_extract(diff.green,
> lut_bits);
> -
> -			diff.blue = lut[i].blue - lut[i - 1].blue;
> -			diff.blue = drm_color_lut_extract(diff.blue,
> lut_bits);
> -
> -			word = FIELD_PREP(DISP_GAMMA_LUT_10BIT_R,
> diff.red);
> -			word |= FIELD_PREP(DISP_GAMMA_LUT_10BIT_G,
> diff.green);
> -			word |= FIELD_PREP(DISP_GAMMA_LUT_10BIT_B,
> diff.blue);
> +	for (cur_bank = 0; cur_bank < num_lut_banks; cur_bank++) {
> +
> +		/* Switch gamma bank and set data mode before writing
> LUT */
> +		if (num_lut_banks > 1) {
> +			lbank_val = FIELD_PREP(DISP_GAMMA_BANK_BANK,
> cur_bank);
> +			writel(lbank_val, regs + DISP_GAMMA_BANK);
> +		}
> +
> +		for (i = 0; i < lut_bank_size; i++) {
> +			int n = (cur_bank * lut_bank_size) + i;
> +			struct drm_color_lut diff, hwlut;
> +
> +			hwlut.red = drm_color_lut_extract(lut[n].red,
> lut_bits);
> +			hwlut.green =
> drm_color_lut_extract(lut[n].green, lut_bits);
> +			hwlut.blue = drm_color_lut_extract(lut[n].blue,
> lut_bits);
> +
> +			if (!lut_diff || (i % 2 == 0)) {
> +				word =
> FIELD_PREP(DISP_GAMMA_LUT_10BIT_R, hwlut.red);
> +				word |=
> FIELD_PREP(DISP_GAMMA_LUT_10BIT_G, hwlut.green);
> +				word |=
> FIELD_PREP(DISP_GAMMA_LUT_10BIT_B, hwlut.blue);
> +			} else {
> +				diff.red = lut[n].red - lut[n - 1].red;
> +				diff.red =
> drm_color_lut_extract(diff.red, lut_bits);
> +
> +				diff.green = lut[n].green - lut[n -
> 1].green;
> +				diff.green =
> drm_color_lut_extract(diff.green, lut_bits);
> +
> +				diff.blue = lut[n].blue - lut[n -
> 1].blue;
> +				diff.blue =
> drm_color_lut_extract(diff.blue, lut_bits);
> +
> +				word =
> FIELD_PREP(DISP_GAMMA_LUT_10BIT_R, diff.red);
> +				word |=
> FIELD_PREP(DISP_GAMMA_LUT_10BIT_G, diff.green);
> +				word |=
> FIELD_PREP(DISP_GAMMA_LUT_10BIT_B, diff.blue);
> +			}
> +			writel(word, (lut_base + i * 4));
>  		}
> -		writel(word, (lut_base + i * 4));
>  	}
>  
>  	/* Enable the gamma table */
> @@ -236,11 +255,13 @@ static int mtk_disp_gamma_remove(struct
> platform_device *pdev)
>  
>  static const struct mtk_disp_gamma_data mt8173_gamma_driver_data = {
>  	.has_dither = true,
> +	.lut_bank_size = 512,
>  	.lut_bits = 10,
>  	.lut_size = 512,
>  };
>  
>  static const struct mtk_disp_gamma_data mt8183_gamma_driver_data = {
> +	.lut_bank_size = 512,
>  	.lut_bits = 10,
>  	.lut_diff = true,
>  	.lut_size = 512,

Re: [PATCH v8 08/13] drm/mediatek: gamma: Support multi-bank gamma LUT

[AngeloGioacchino Del Regno]

Il 02/08/23 06:12, CK Hu (胡俊光) ha scritto:
> Hi, Angelo:
> 
> On Tue, 2023-08-01 at 13:58 +0200, AngeloGioacchino Del Regno wrote:
>> Newer Gamma IP have got multiple LUT banks: support specifying the
>> size of the LUT banks and handle bank-switching before programming
>> the LUT in mtk_gamma_set_common() in preparation for adding support
>> for MT8195 and newer SoCs.
>>
>> Suggested-by: Jason-JH.Lin <jason-jh.lin@mediatek.com>
>> [Angelo: Refactored original commit]
>> Signed-off-by: AngeloGioacchino Del Regno <
>> angelogioacchino.delregno@collabora.com>
>> Reviewed-by: Alexandre Mergnat <amergnat@baylibre.com>
>> ---
>>   drivers/gpu/drm/mediatek/mtk_disp_gamma.c | 73 +++++++++++++++----
>> ----
>>   1 file changed, 47 insertions(+), 26 deletions(-)
>>
>> diff --git a/drivers/gpu/drm/mediatek/mtk_disp_gamma.c
>> b/drivers/gpu/drm/mediatek/mtk_disp_gamma.c
>> index a6f7af1a9e8e..fb7c3650a9f7 100644
>> --- a/drivers/gpu/drm/mediatek/mtk_disp_gamma.c
>> +++ b/drivers/gpu/drm/mediatek/mtk_disp_gamma.c
>> @@ -24,6 +24,8 @@
>>   #define DISP_GAMMA_SIZE				0x0030
>>   #define DISP_GAMMA_SIZE_HSIZE				GENMASK
>> (28, 16)
>>   #define DISP_GAMMA_SIZE_VSIZE				GENMASK
>> (12, 0)
>> +#define DISP_GAMMA_BANK				0x0100
>> +#define DISP_GAMMA_BANK_BANK				GENMASK(1, 0)
>>   #define DISP_GAMMA_LUT				0x0700
>>   
>>   #define DISP_GAMMA_LUT_10BIT_R			GENMASK(29, 20)
>> @@ -32,10 +34,12 @@
>>   
>>   #define LUT_10BIT_MASK				0x03ff
>>   #define LUT_BITS_DEFAULT			10
>> +#define LUT_BANK_SIZE_DEFAULT			512
>>   
>>   struct mtk_disp_gamma_data {
>>   	bool has_dither;
>>   	bool lut_diff;
>> +	u16 lut_bank_size;
>>   	u16 lut_size;
>>   	u8 lut_bits;
>>   };
>> @@ -80,7 +84,9 @@ void mtk_gamma_set_common(struct device *dev, void
>> __iomem *regs,
>>   	void __iomem *lut_base;
>>   	bool lut_diff;
>>   	u8 lut_bits;
>> -	u32 cfg_val, word;
>> +	u16 lut_bank_size;
>> +	u32 cfg_val, lbank_val, word;
>> +	int cur_bank, num_lut_banks;
>>   
>>   	/* If there's no gamma lut there's nothing to do here. */
>>   	if (!state->gamma_lut)
>> @@ -91,41 +97,54 @@ void mtk_gamma_set_common(struct device *dev,
>> void __iomem *regs,
>>   
>>   	if (gamma && gamma->data) {
>>   		lut_diff = gamma->data->lut_diff;
>> +		lut_bank_size = gamma->data->lut_bank_size;
>>   		lut_bits = gamma->data->lut_bits;
>>   	} else {
>>   		lut_diff = false;
>> +		lut_bank_size = LUT_BANK_SIZE_DEFAULT;
> 
> LUT_BANK_SIZE_DEFAULT is only for AAL driver, so place it in AAL driver
> and pass it into this function.
> 

I completely dislike having a function taking too many parameters.

Since mtk_gamma_set() in DISP_GAMMA will anyway expand in the future to
support newer hardware, I'm thinking about just removing AAL support from
this function and duplicate the few (15 or something) lines of code in
mtk_disp_aal instead, so that we stop commonizing the mtk_gamma_set for
both DISP_AAL and DISP_GAMMA.

Any opinions on that?

Regards,
Angelo

> Regards,
> CK
> 

Re: [PATCH v8 08/13] drm/mediatek: gamma: Support multi-bank gamma LUT

[CK Hu (胡俊光)]

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Hi, Angelo:

On Wed, 2023-08-02 at 10:30 +0200, AngeloGioacchino Del Regno wrote:
> Il 02/08/23 06:12, CK Hu (胡俊光) ha scritto:
> > Hi, Angelo:
> > 
> > On Tue, 2023-08-01 at 13:58 +0200, AngeloGioacchino Del Regno
> > wrote:
> > > Newer Gamma IP have got multiple LUT banks: support specifying
> > > the
> > > size of the LUT banks and handle bank-switching before
> > > programming
> > > the LUT in mtk_gamma_set_common() in preparation for adding
> > > support
> > > for MT8195 and newer SoCs.
> > > 
> > > Suggested-by: Jason-JH.Lin <jason-jh.lin@mediatek.com>
> > > [Angelo: Refactored original commit]
> > > Signed-off-by: AngeloGioacchino Del Regno <
> > > angelogioacchino.delregno@collabora.com>
> > > Reviewed-by: Alexandre Mergnat <amergnat@baylibre.com>
> > > ---
> > >   drivers/gpu/drm/mediatek/mtk_disp_gamma.c | 73 +++++++++++++++-
> > > ---
> > > ----
> > >   1 file changed, 47 insertions(+), 26 deletions(-)
> > > 
> > > diff --git a/drivers/gpu/drm/mediatek/mtk_disp_gamma.c
> > > b/drivers/gpu/drm/mediatek/mtk_disp_gamma.c
> > > index a6f7af1a9e8e..fb7c3650a9f7 100644
> > > --- a/drivers/gpu/drm/mediatek/mtk_disp_gamma.c
> > > +++ b/drivers/gpu/drm/mediatek/mtk_disp_gamma.c
> > > @@ -24,6 +24,8 @@
> > >   #define DISP_GAMMA_SIZE				0x0030
> > >   #define DISP_GAMMA_SIZE_HSIZE				GENMASK
> > > (28, 16)
> > >   #define DISP_GAMMA_SIZE_VSIZE				GENMASK
> > > (12, 0)
> > > +#define DISP_GAMMA_BANK				0x0100
> > > +#define DISP_GAMMA_BANK_BANK				GENMASK
> > > (1, 0)
> > >   #define DISP_GAMMA_LUT				0x0700
> > >   
> > >   #define DISP_GAMMA_LUT_10BIT_R			GENMASK(29, 20)
> > > @@ -32,10 +34,12 @@
> > >   
> > >   #define LUT_10BIT_MASK				0x03ff
> > >   #define LUT_BITS_DEFAULT			10
> > > +#define LUT_BANK_SIZE_DEFAULT			512
> > >   
> > >   struct mtk_disp_gamma_data {
> > >   	bool has_dither;
> > >   	bool lut_diff;
> > > +	u16 lut_bank_size;
> > >   	u16 lut_size;
> > >   	u8 lut_bits;
> > >   };
> > > @@ -80,7 +84,9 @@ void mtk_gamma_set_common(struct device *dev,
> > > void
> > > __iomem *regs,
> > >   	void __iomem *lut_base;
> > >   	bool lut_diff;
> > >   	u8 lut_bits;
> > > -	u32 cfg_val, word;
> > > +	u16 lut_bank_size;
> > > +	u32 cfg_val, lbank_val, word;
> > > +	int cur_bank, num_lut_banks;
> > >   
> > >   	/* If there's no gamma lut there's nothing to do here.
> > > */
> > >   	if (!state->gamma_lut)
> > > @@ -91,41 +97,54 @@ void mtk_gamma_set_common(struct device *dev,
> > > void __iomem *regs,
> > >   
> > >   	if (gamma && gamma->data) {
> > >   		lut_diff = gamma->data->lut_diff;
> > > +		lut_bank_size = gamma->data->lut_bank_size;
> > >   		lut_bits = gamma->data->lut_bits;
> > >   	} else {
> > >   		lut_diff = false;
> > > +		lut_bank_size = LUT_BANK_SIZE_DEFAULT;
> > 
> > LUT_BANK_SIZE_DEFAULT is only for AAL driver, so place it in AAL
> > driver
> > and pass it into this function.
> > 
> 
> I completely dislike having a function taking too many parameters.
> 
> Since mtk_gamma_set() in DISP_GAMMA will anyway expand in the future
> to
> support newer hardware, I'm thinking about just removing AAL support
> from
> this function and duplicate the few (15 or something) lines of code
> in
> mtk_disp_aal instead, so that we stop commonizing the mtk_gamma_set
> for
> both DISP_AAL and DISP_GAMMA.
> 
> Any opinions on that?

OK, let's stop commonizing the mtk_gamma_set
().

Regards,
CK

> 
> Regards,
> Angelo
> 
> > Regards,
> > CK
> > 
> 
>