media: rcar-vin: Add support for Gen3 UDS (Up Down Scaler)

Add support for the UDS (Up Down Scaler) found in some Gen3 SoCs.

Not all Gen3 SoCs have scalers, and for those that do it's only
available to the master node of each VIN group. The setup for which SoCs
and nodes have access to a scaler are dealt with at probe time and then
function transparently reusing the schema from the already present Gen2
scaler.
Signed-off-by: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab@kernel.org>

drivers/media/platform/renesas/rcar-vin/rcar-core.c

@@ -1180,6 +1180,7 @@ static const struct rvin_info rcar_info_r8a7795 = {
 	.max_width = 4096,
 	.max_height = 4096,
 	.routes = rcar_info_r8a7795_routes,
+	.scaler = rvin_scaler_gen3,
 };
 
 static const struct rvin_group_route rcar_info_r8a7795es1_routes[] = {
@@ -1215,6 +1216,7 @@ static const struct rvin_info rcar_info_r8a7796 = {
 	.max_width = 4096,
 	.max_height = 4096,
 	.routes = rcar_info_r8a7796_routes,
+	.scaler = rvin_scaler_gen3,
 };
 
 static const struct rvin_group_route rcar_info_r8a77965_routes[] = {
@@ -1232,6 +1234,7 @@ static const struct rvin_info rcar_info_r8a77965 = {
 	.max_width = 4096,
 	.max_height = 4096,
 	.routes = rcar_info_r8a77965_routes,
+	.scaler = rvin_scaler_gen3,
 };
 
 static const struct rvin_group_route rcar_info_r8a77970_routes[] = {
@@ -1274,6 +1277,7 @@ static const struct rvin_info rcar_info_r8a77990 = {
 	.max_width = 4096,
 	.max_height = 4096,
 	.routes = rcar_info_r8a77990_routes,
+	.scaler = rvin_scaler_gen3,
 };
 
 static const struct rvin_group_route rcar_info_r8a77995_routes[] = {
@@ -1287,6 +1291,7 @@ static const struct rvin_info rcar_info_r8a77995 = {
 	.max_width = 4096,
 	.max_height = 4096,
 	.routes = rcar_info_r8a77995_routes,
+	.scaler = rvin_scaler_gen3,
 };
 
 static const struct rvin_info rcar_info_r8a779a0 = {
@@ -1415,6 +1420,10 @@ static int rcar_vin_probe(struct platform_device *pdev)
 		ret = rvin_isp_init(vin);
 	} else if (vin->info->use_mc) {
 		ret = rvin_csi2_init(vin);
+
+		if (vin->info->scaler &&
+		    rvin_group_id_to_master(vin->id) == vin->id)
+			vin->scaler = vin->info->scaler;
 	} else {
 		ret = rvin_parallel_init(vin);
 

drivers/media/platform/renesas/rcar-vin/rcar-dma.c

@@ -74,6 +74,10 @@
 
 /* Register offsets specific for Gen3 */
 #define VNCSI_IFMD_REG		0x20 /* Video n CSI2 Interface Mode Register */
+#define VNUDS_CTRL_REG		0x80 /* Video n scaling control register */
+#define VNUDS_SCALE_REG		0x84 /* Video n scaling factor register */
+#define VNUDS_PASS_BWIDTH_REG	0x90 /* Video n passband register */
+#define VNUDS_CLIP_SIZE_REG	0xa4 /* Video n UDS output size clipping reg */
 
 /* Register bit fields for R-Car VIN */
 /* Video n Main Control Register bits */
@@ -140,6 +144,9 @@
 #define VNCSI_IFMD_DES0		(1 << 25)
 #define VNCSI_IFMD_CSI_CHSEL(n) (((n) & 0xf) << 0)
 
+/* Video n scaling control register (Gen3) */
+#define VNUDS_CTRL_AMD		(1 << 30)
+
 struct rvin_buffer {
 	struct vb2_v4l2_buffer vb;
 	struct list_head list;
@@ -591,6 +598,69 @@ void rvin_scaler_gen2(struct rvin_dev *vin)
 		0, 0);
 }
 
+static unsigned int rvin_uds_scale_ratio(unsigned int in, unsigned int out)
+{
+	unsigned int ratio;
+
+	ratio = in * 4096 / out;
+	return ratio >= 0x10000 ? 0xffff : ratio;
+}
+
+static unsigned int rvin_uds_filter_width(unsigned int ratio)
+{
+	if (ratio >= 0x1000)
+		return 64 * (ratio & 0xf000) / ratio;
+
+	return 64;
+}
+
+void rvin_scaler_gen3(struct rvin_dev *vin)
+{
+	unsigned int ratio_h, ratio_v;
+	unsigned int bwidth_h, bwidth_v;
+	u32 vnmc, clip_size;
+
+	vnmc = rvin_read(vin, VNMC_REG);
+
+	/* Disable scaler if not needed. */
+	if (!rvin_scaler_needed(vin)) {
+		rvin_write(vin, vnmc & ~VNMC_SCLE, VNMC_REG);
+		return;
+	}
+
+	ratio_h = rvin_uds_scale_ratio(vin->crop.width, vin->compose.width);
+	bwidth_h = rvin_uds_filter_width(ratio_h);
+
+	ratio_v = rvin_uds_scale_ratio(vin->crop.height, vin->compose.height);
+	bwidth_v = rvin_uds_filter_width(ratio_v);
+
+	clip_size = vin->compose.width << 16;
+
+	switch (vin->format.field) {
+	case V4L2_FIELD_INTERLACED_TB:
+	case V4L2_FIELD_INTERLACED_BT:
+	case V4L2_FIELD_INTERLACED:
+	case V4L2_FIELD_SEQ_TB:
+	case V4L2_FIELD_SEQ_BT:
+		clip_size |= vin->compose.height / 2;
+		break;
+	default:
+		clip_size |= vin->compose.height;
+		break;
+	}
+
+	rvin_write(vin, vnmc | VNMC_SCLE, VNMC_REG);
+	rvin_write(vin, VNUDS_CTRL_AMD, VNUDS_CTRL_REG);
+	rvin_write(vin, (ratio_h << 16) | ratio_v, VNUDS_SCALE_REG);
+	rvin_write(vin, (bwidth_h << 16) | bwidth_v, VNUDS_PASS_BWIDTH_REG);
+	rvin_write(vin, clip_size, VNUDS_CLIP_SIZE_REG);
+
+	vin_dbg(vin, "Pre-Clip: %ux%u@%u:%u Post-Clip: %ux%u@%u:%u\n",
+		vin->crop.width, vin->crop.height, vin->crop.left,
+		vin->crop.top, vin->compose.width, vin->compose.height,
+		vin->compose.left, vin->compose.top);
+}
+
 void rvin_crop_scale_comp(struct rvin_dev *vin)
 {
 	const struct rvin_video_format *fmt;

drivers/media/platform/renesas/rcar-vin/rcar-v4l2.c

@@ -918,6 +918,9 @@ static const struct v4l2_ioctl_ops rvin_mc_ioctl_ops = {
 	.vidioc_s_fmt_vid_cap		= rvin_mc_s_fmt_vid_cap,
 	.vidioc_enum_fmt_vid_cap	= rvin_enum_fmt_vid_cap,
 
+	.vidioc_g_selection		= rvin_g_selection,
+	.vidioc_s_selection		= rvin_s_selection,
+
 	.vidioc_reqbufs			= vb2_ioctl_reqbufs,
 	.vidioc_create_bufs		= vb2_ioctl_create_bufs,
 	.vidioc_querybuf		= vb2_ioctl_querybuf,

drivers/media/platform/renesas/rcar-vin/rcar-vin.h

@@ -308,6 +308,7 @@ const struct rvin_video_format *rvin_format_from_pixel(struct rvin_dev *vin,
 
 /* Cropping, composing and scaling */
 void rvin_scaler_gen2(struct rvin_dev *vin);
+void rvin_scaler_gen3(struct rvin_dev *vin);
 void rvin_crop_scale_comp(struct rvin_dev *vin);
 
 int rvin_set_channel_routing(struct rvin_dev *vin, u8 chsel);