gpu: ipu-v3: ipu-ic-csc: Add support for limited range encoding

Add support for encodings to or from limited range quantization.
Signed-off-by: Steve Longerbeam <slongerbeam@gmail.com>
Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>

drivers/gpu/ipu-v3/ipu-ic-csc.c

@@ -10,6 +10,10 @@
 #include <linux/sizes.h>
 #include "ipu-prv.h"
 
+#define QUANT_MAP(q)					\
+	((q) == V4L2_QUANTIZATION_FULL_RANGE ||		\
+	 (q) == V4L2_QUANTIZATION_DEFAULT ? 0 : 1)
+
 /* identity matrix */
 static const struct ipu_ic_csc_params identity = {
 	.coeff = {
@@ -21,12 +25,87 @@ static const struct ipu_ic_csc_params identity = {
 	.scale = 2,
 };
 
+/*
+ * RGB full-range to RGB limited-range
+ *
+ * R_lim = 0.8588 * R_full + 16
+ * G_lim = 0.8588 * G_full + 16
+ * B_lim = 0.8588 * B_full + 16
+ */
+static const struct ipu_ic_csc_params rgbf2rgbl = {
+	.coeff = {
+		{  220,    0,    0, },
+		{    0,  220,    0, },
+		{    0,    0,  220, },
+	},
+	.offset = { 64, 64, 64, },
+	.scale = 1,
+};
+
+/*
+ * RGB limited-range to RGB full-range
+ *
+ * R_full = 1.1644 * (R_lim - 16)
+ * G_full = 1.1644 * (G_lim - 16)
+ * B_full = 1.1644 * (B_lim - 16)
+ */
+static const struct ipu_ic_csc_params rgbl2rgbf = {
+	.coeff = {
+		{  149,    0,    0, },
+		{    0,  149,    0, },
+		{    0,    0,  149, },
+	},
+	.offset = { -37, -37, -37, },
+	.scale = 2,
+};
+
+/*
+ * YUV full-range to YUV limited-range
+ *
+ * Y_lim  = 0.8588 * Y_full + 16
+ * Cb_lim = 0.8784 * (Cb_full - 128) + 128
+ * Cr_lim = 0.8784 * (Cr_full - 128) + 128
+ */
+static const struct ipu_ic_csc_params yuvf2yuvl = {
+	.coeff = {
+		{  220,    0,    0, },
+		{    0,  225,    0, },
+		{    0,    0,  225, },
+	},
+	.offset = { 64, 62, 62, },
+	.scale = 1,
+	.sat = true,
+};
+
+/*
+ * YUV limited-range to YUV full-range
+ *
+ * Y_full  = 1.1644 * (Y_lim - 16)
+ * Cb_full = 1.1384 * (Cb_lim - 128) + 128
+ * Cr_full = 1.1384 * (Cr_lim - 128) + 128
+ */
+static const struct ipu_ic_csc_params yuvl2yuvf = {
+	.coeff = {
+		{  149,    0,    0, },
+		{    0,  146,    0, },
+		{    0,    0,  146, },
+	},
+	.offset = { -37, -35, -35, },
+	.scale = 2,
+};
+
 static const struct ipu_ic_csc_params *rgb2rgb[] = {
 	&identity,
+	&rgbf2rgbl,
+	&rgbl2rgbf,
+	&identity,
 };
 
 static const struct ipu_ic_csc_params *yuv2yuv[] = {
 	&identity,
+	&yuvf2yuvl,
+	&yuvl2yuvf,
+	&identity,
 };
 
 /*
@@ -46,6 +125,41 @@ static const struct ipu_ic_csc_params rgbf2yuvf_601 = {
 	.scale = 1,
 };
 
+/* BT.601 RGB full-range to YUV limited-range */
+static const struct ipu_ic_csc_params rgbf2yuvl_601 = {
+	.coeff = {
+		{   66,  129,   25, },
+		{  -38,  -74,  112, },
+		{  112,  -94,  -18, },
+	},
+	.offset = { 64, 512, 512, },
+	.scale = 1,
+	.sat = true,
+};
+
+/* BT.601 RGB limited-range to YUV full-range */
+static const struct ipu_ic_csc_params rgbl2yuvf_601 = {
+	.coeff = {
+		{   89,  175,   34, },
+		{  -50,  -99,  149, },
+		{  149, -125,  -24, },
+	},
+	.offset = { -75, 512, 512, },
+	.scale = 1,
+};
+
+/* BT.601 RGB limited-range to YUV limited-range */
+static const struct ipu_ic_csc_params rgbl2yuvl_601 = {
+	.coeff = {
+		{   77,  150,   29, },
+		{  -44,  -87,  131, },
+		{  131, -110,  -21, },
+	},
+	.offset = { 0, 512, 512, },
+	.scale = 1,
+	.sat = true,
+};
+
 /*
  * BT.601 YUV full-range to RGB full-range
  *
@@ -69,39 +183,77 @@ static const struct ipu_ic_csc_params yuvf2rgbf_601 = {
 	.scale = 2,
 };
 
+/* BT.601 YUV full-range to RGB limited-range */
+static const struct ipu_ic_csc_params yuvf2rgbl_601 = {
+	.coeff = {
+		{  110,    0,  154, },
+		{  110,  -38,  -78, },
+		{  110,  195,    0, },
+	},
+	.offset = { -276, 265, -358, },
+	.scale = 2,
+};
+
+/* BT.601 YUV limited-range to RGB full-range */
+static const struct ipu_ic_csc_params yuvl2rgbf_601 = {
+	.coeff = {
+		{   75,    0,  102, },
+		{   75,  -25,  -52, },
+		{   75,  129,    0, },
+	},
+	.offset = { -223, 136, -277, },
+	.scale = 3,
+};
+
+/* BT.601 YUV limited-range to RGB limited-range */
+static const struct ipu_ic_csc_params yuvl2rgbl_601 = {
+	.coeff = {
+		{  128,    0,  175, },
+		{  128,  -43,  -89, },
+		{  128,  222,    0, },
+	},
+	.offset = { -351, 265, -443, },
+	.scale = 2,
+};
+
 static const struct ipu_ic_csc_params *rgb2yuv_601[] = {
 	&rgbf2yuvf_601,
+	&rgbf2yuvl_601,
+	&rgbl2yuvf_601,
+	&rgbl2yuvl_601,
 };
 
 static const struct ipu_ic_csc_params *yuv2rgb_601[] = {
 	&yuvf2rgbf_601,
+	&yuvf2rgbl_601,
+	&yuvl2rgbf_601,
+	&yuvl2rgbl_601,
 };
 
 static int calc_csc_coeffs(struct ipu_ic_csc *csc)
 {
+	const struct ipu_ic_csc_params **params_tbl;
+	int tbl_idx;
+
 	if (csc->out_cs.enc != V4L2_YCBCR_ENC_601)
 		return -ENOTSUPP;
 
-	if ((csc->in_cs.cs == IPUV3_COLORSPACE_YUV &&
-	     csc->in_cs.quant != V4L2_QUANTIZATION_FULL_RANGE) ||
-	    (csc->out_cs.cs == IPUV3_COLORSPACE_YUV &&
-	     csc->out_cs.quant != V4L2_QUANTIZATION_FULL_RANGE))
-		return -ENOTSUPP;
-
-	if ((csc->in_cs.cs == IPUV3_COLORSPACE_RGB &&
-	     csc->in_cs.quant != V4L2_QUANTIZATION_FULL_RANGE) ||
-	    (csc->out_cs.cs == IPUV3_COLORSPACE_RGB &&
-	     csc->out_cs.quant != V4L2_QUANTIZATION_FULL_RANGE))
-		return -ENOTSUPP;
+	tbl_idx = (QUANT_MAP(csc->in_cs.quant) << 1) |
+		QUANT_MAP(csc->out_cs.quant);
 
 	if (csc->in_cs.cs == csc->out_cs.cs) {
 		csc->params = (csc->in_cs.cs == IPUV3_COLORSPACE_YUV) ?
-			*yuv2yuv[0] : *rgb2rgb[0];
+			*yuv2yuv[tbl_idx] : *rgb2rgb[tbl_idx];
+
 		return 0;
 	}
 
-	csc->params = (csc->in_cs.cs == IPUV3_COLORSPACE_YUV) ?
-		*yuv2rgb_601[0] : *rgb2yuv_601[0];
+	/* YUV <-> RGB encoding is required */
+
+	params_tbl = (csc->in_cs.cs == IPUV3_COLORSPACE_YUV) ?
+		yuv2rgb_601 : rgb2yuv_601;
+
+	csc->params = *params_tbl[tbl_idx];
 
 	return 0;
 }