[PATCH v2 3/8] drm/sun4i: Add support for DE33 CSC

[Jernej Skrabec <jernej.skrabec@gmail.com>]

From: Jernej Skrabec <jernej.skrabec@gmail.com>

DE33 has channel CSC units (for each plane separately) so pipeline can
be configured to output in desired colorspace.

Reviewed-by: Chen-Yu Tsai <wens@kernel.org>
Signed-off-by: Jernej Skrabec <jernej.skrabec@gmail.com>
---
Changes from v1:
- collected tag

 drivers/gpu/drm/sun4i/sun8i_csc.c | 71 +++++++++++++++++++++++++++++++
 drivers/gpu/drm/sun4i/sun8i_csc.h |  5 +++
 2 files changed, 76 insertions(+)

diff --git a/drivers/gpu/drm/sun4i/sun8i_csc.c b/drivers/gpu/drm/sun4i/sun8i_csc.c
index ce81c12f511d..70fc9b017d17 100644
--- a/drivers/gpu/drm/sun4i/sun8i_csc.c
+++ b/drivers/gpu/drm/sun4i/sun8i_csc.c
@@ -205,6 +205,72 @@ static void sun8i_de3_ccsc_setup(struct regmap *map, int layer,
 			   mask, val);
 }
 
+/* extract constant from high word and invert sign if necessary */
+static u32 sun8i_de33_ccsc_get_constant(u32 value)
+{
+	value >>= 16;
+
+	if (value & BIT(15))
+		return 0x400 - (value & 0x3ff);
+
+	return value;
+}
+
+static void sun8i_de33_convert_table(const u32 *src, u32 *dst)
+{
+	dst[0] = sun8i_de33_ccsc_get_constant(src[3]);
+	dst[1] = sun8i_de33_ccsc_get_constant(src[7]);
+	dst[2] = sun8i_de33_ccsc_get_constant(src[11]);
+	memcpy(&dst[3], src, sizeof(u32) * 12);
+	dst[6] &= 0xffff;
+	dst[10] &= 0xffff;
+	dst[14] &= 0xffff;
+}
+
+static void sun8i_de33_ccsc_setup(struct regmap *map, int layer,
+				  enum sun8i_csc_mode mode,
+				  enum drm_color_encoding encoding,
+				  enum drm_color_range range)
+{
+	u32 addr, val, base, csc[15];
+	const u32 *table;
+	int i;
+
+	table = yuv2rgb_de3[range][encoding];
+	base = DE33_CCSC_BASE + layer * DE33_CH_SIZE;
+
+	switch (mode) {
+	case SUN8I_CSC_MODE_OFF:
+		val = 0;
+		break;
+	case SUN8I_CSC_MODE_YUV2RGB:
+		val = SUN8I_CSC_CTRL_EN;
+		sun8i_de33_convert_table(table, csc);
+		regmap_bulk_write(map, SUN50I_CSC_COEFF(base, 0), csc, 15);
+		break;
+	case SUN8I_CSC_MODE_YVU2RGB:
+		val = SUN8I_CSC_CTRL_EN;
+		sun8i_de33_convert_table(table, csc);
+		for (i = 0; i < 15; i++) {
+			addr = SUN50I_CSC_COEFF(base, i);
+			if (i > 3) {
+				if (((i - 3) & 3) == 1)
+					addr = SUN50I_CSC_COEFF(base, i + 1);
+				else if (((i - 3) & 3) == 2)
+					addr = SUN50I_CSC_COEFF(base, i - 1);
+			}
+			regmap_write(map, addr, csc[i]);
+		}
+		break;
+	default:
+		val = 0;
+		DRM_WARN("Wrong CSC mode specified.\n");
+		return;
+	}
+
+	regmap_write(map, SUN8I_CSC_CTRL(base), val);
+}
+
 static u32 sun8i_csc_get_mode(struct drm_plane_state *state)
 {
 	const struct drm_format_info *format;
@@ -238,6 +304,11 @@ void sun8i_csc_config(struct sun8i_layer *layer,
 				     mode, state->color_encoding,
 				     state->color_range);
 		return;
+	} else if (layer->cfg->de_type == SUN8I_MIXER_DE33) {
+		sun8i_de33_ccsc_setup(layer->regs, layer->channel,
+				      mode, state->color_encoding,
+				      state->color_range);
+		return;
 	}
 
 	base = ccsc_base[layer->cfg->ccsc][layer->channel];
diff --git a/drivers/gpu/drm/sun4i/sun8i_csc.h b/drivers/gpu/drm/sun4i/sun8i_csc.h
index 2a4b79599610..d2ba5f8611aa 100644
--- a/drivers/gpu/drm/sun4i/sun8i_csc.h
+++ b/drivers/gpu/drm/sun4i/sun8i_csc.h
@@ -18,9 +18,14 @@ struct sun8i_layer;
 #define CCSC10_OFFSET 0xA0000
 #define CCSC11_OFFSET 0xF0000
 
+#define DE33_CCSC_BASE 0x800
+
 #define SUN8I_CSC_CTRL(base)		((base) + 0x0)
 #define SUN8I_CSC_COEFF(base, i)	((base) + 0x10 + 4 * (i))
 
+#define SUN50I_CSC_COEFF(base, i)	((base) + 0x04 + 4 * (i))
+#define SUN50I_CSC_ALPHA(base)		((base) + 0x40)
+
 #define SUN8I_CSC_CTRL_EN		BIT(0)
 
 void sun8i_csc_config(struct sun8i_layer *layer,
-- 
2.54.0