media: tegra-video: Add support for x8 captures with gang ports

Tegra VI/CSI hardware don't have native 8 lane capture support.

Each CSI port has max 4 lanes only. So for x8 captures, consecutive
ports are ganged up for left half and right half captures on to each
x4 ports with buffer offsets based on source image split width to align
side-by-side.

All ports in gang are configured together during the corresponding
video device node streaming for x8 captures.

x8 capture with gang ports are supported with HDMI-to-CSI bridges
where they split 4K image into left half onto one x4 port and
right half onto second x4 port.
Signed-off-by: Sowjanya Komatineni <skomatineni@nvidia.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>

drivers/staging/media/tegra-video/csi.c

@@ -253,13 +253,14 @@ static unsigned int csi_get_pixel_rate(struct tegra_csi_channel *csi_chan)
 }
 
 void tegra_csi_calc_settle_time(struct tegra_csi_channel *csi_chan,
+				u8 csi_port_num,
 				u8 *clk_settle_time,
 				u8 *ths_settle_time)
 {
 	struct tegra_csi *csi = csi_chan->csi;
 	unsigned int cil_clk_mhz;
 	unsigned int pix_clk_mhz;
-	int clk_idx = (csi_chan->csi_port_num >> 1) + 1;
+	int clk_idx = (csi_port_num >> 1) + 1;
 
 	cil_clk_mhz = clk_get_rate(csi->clks[clk_idx].clk) / MHZ;
 	pix_clk_mhz = csi_get_pixel_rate(csi_chan) / MHZ;
@@ -410,7 +411,7 @@ static int tegra_csi_channel_alloc(struct tegra_csi *csi,
 				   unsigned int num_pads)
 {
 	struct tegra_csi_channel *chan;
-	int ret = 0;
+	int ret = 0, i;
 
 	chan = kzalloc(sizeof(*chan), GFP_KERNEL);
 	if (!chan)
@@ -418,8 +419,21 @@ static int tegra_csi_channel_alloc(struct tegra_csi *csi,
 
 	list_add_tail(&chan->list, &csi->csi_chans);
 	chan->csi = csi;
-	chan->csi_port_num = port_num;
-	chan->numlanes = lanes;
+	/*
+	 * Each CSI brick has maximum of 4 lanes.
+	 * For lanes more than 4, use multiple of immediate CSI bricks as gang.
+	 */
+	if (lanes <= CSI_LANES_PER_BRICK) {
+		chan->numlanes = lanes;
+		chan->numgangports = 1;
+	} else {
+		chan->numlanes = CSI_LANES_PER_BRICK;
+		chan->numgangports = lanes / CSI_LANES_PER_BRICK;
+	}
+
+	for (i = 0; i < chan->numgangports; i++)
+		chan->csi_port_nums[i] = port_num + i * CSI_PORTS_PER_BRICK;
+
 	chan->of_node = node;
 	chan->numpads = num_pads;
 	if (num_pads & 0x2) {
@@ -500,7 +514,14 @@ static int tegra_csi_channels_alloc(struct tegra_csi *csi)
 		}
 
 		lanes = v4l2_ep.bus.mipi_csi2.num_data_lanes;
-		if (!lanes || ((lanes & (lanes - 1)) != 0)) {
+		/*
+		 * Each CSI brick has maximum 4 data lanes.
+		 * For lanes more than 4, validate lanes to be multiple of 4
+		 * so multiple of consecutive CSI bricks can be ganged up for
+		 * streaming.
+		 */
+		if (!lanes || ((lanes & (lanes - 1)) != 0) ||
+		    (lanes > CSI_LANES_PER_BRICK && ((portno & 1) != 0))) {
 			dev_err(csi->dev, "invalid data-lanes %d for %pOF\n",
 				lanes, channel);
 			ret = -EINVAL;
@@ -544,7 +565,7 @@ static int tegra_csi_channel_init(struct tegra_csi_channel *chan)
 	subdev->dev = csi->dev;
 	if (IS_ENABLED(CONFIG_VIDEO_TEGRA_TPG))
 		snprintf(subdev->name, V4L2_SUBDEV_NAME_SIZE, "%s-%d", "tpg",
-			 chan->csi_port_num);
+			 chan->csi_port_nums[0]);
 	else
 		snprintf(subdev->name, V4L2_SUBDEV_NAME_SIZE, "%s",
 			 kbasename(chan->of_node->full_name));
@@ -596,7 +617,7 @@ static int tegra_csi_channels_init(struct tegra_csi *csi)
 		if (ret) {
 			dev_err(csi->dev,
 				"failed to initialize channel-%d: %d\n",
-				chan->csi_port_num, ret);
+				chan->csi_port_nums[0], ret);
 			return ret;
 		}
 	}

drivers/staging/media/tegra-video/csi.h

@@ -17,6 +17,10 @@
  * CILB.
  */
 #define CSI_PORTS_PER_BRICK	2
+#define CSI_LANES_PER_BRICK	4
+
+/* Maximum 2 CSI x4 ports can be ganged up for streaming */
+#define GANG_PORTS_MAX	2
 
 /* each CSI channel can have one sink and one source pads */
 #define TEGRA_CSI_PADS_NUM	2
@@ -43,8 +47,10 @@ struct tegra_csi;
  * @numpads: number of pads.
  * @csi: Tegra CSI device structure
  * @of_node: csi device tree node
- * @numlanes: number of lanes used per port/channel
- * @csi_port_num: CSI channel port number
+ * @numgangports: number of immediate ports ganged up to meet the
+ *             channel bus-width
+ * @numlanes: number of lanes used per port
+ * @csi_port_nums: CSI channel port numbers
  * @pg_mode: test pattern generator mode for channel
  * @format: active format of the channel
  * @framerate: active framerate for TPG
@@ -60,8 +66,9 @@ struct tegra_csi_channel {
 	unsigned int numpads;
 	struct tegra_csi *csi;
 	struct device_node *of_node;
+	u8 numgangports;
 	unsigned int numlanes;
-	u8 csi_port_num;
+	u8 csi_port_nums[GANG_PORTS_MAX];
 	u8 pg_mode;
 	struct v4l2_mbus_framefmt format;
 	unsigned int framerate;
@@ -150,6 +157,7 @@ extern const struct tegra_csi_soc tegra210_csi_soc;
 
 void tegra_csi_error_recover(struct v4l2_subdev *subdev);
 void tegra_csi_calc_settle_time(struct tegra_csi_channel *csi_chan,
+				u8 csi_port_num,
 				u8 *clk_settle_time,
 				u8 *ths_settle_time);
 #endif

drivers/staging/media/tegra-video/vi.c

@@ -30,7 +30,6 @@
 #include "vi.h"
 #include "video.h"
 
-#define SURFACE_ALIGN_BYTES		64
 #define MAX_CID_CONTROLS		1
 
 static const struct tegra_video_format tegra_default_format = {
@@ -573,6 +572,14 @@ static int tegra_channel_try_format(struct file *file, void *fh,
 	return __tegra_channel_try_format(chan, &format->fmt.pix);
 }
 
+static void tegra_channel_update_gangports(struct tegra_vi_channel *chan)
+{
+	if (chan->format.width <= 1920)
+		chan->numgangports = 1;
+	else
+		chan->numgangports = chan->totalports;
+}
+
 static int tegra_channel_set_format(struct file *file, void *fh,
 				    struct v4l2_format *format)
 {
@@ -606,6 +613,7 @@ static int tegra_channel_set_format(struct file *file, void *fh,
 
 	chan->format = *pix;
 	chan->fmtinfo = fmtinfo;
+	tegra_channel_update_gangports(chan);
 
 	return 0;
 }
@@ -638,6 +646,7 @@ static int tegra_channel_set_subdev_active_fmt(struct tegra_vi_channel *chan)
 	chan->format.sizeimage = chan->format.bytesperline *
 				 chan->format.height;
 	tegra_channel_fmt_align(chan, &chan->format, chan->fmtinfo->bpp);
+	tegra_channel_update_gangports(chan);
 
 	return 0;
 }
@@ -806,6 +815,7 @@ static int tegra_channel_s_dv_timings(struct file *file, void *fh,
 	chan->format.bytesperline = bt->width * chan->fmtinfo->bpp;
 	chan->format.sizeimage = chan->format.bytesperline * bt->height;
 	tegra_channel_fmt_align(chan, &chan->format, chan->fmtinfo->bpp);
+	tegra_channel_update_gangports(chan);
 
 	return 0;
 }
@@ -1092,12 +1102,21 @@ static int vi_fmts_bitmap_init(struct tegra_vi_channel *chan)
 	return 0;
 }
 
+static void tegra_channel_host1x_syncpts_free(struct tegra_vi_channel *chan)
+{
+	int i;
+
+	for (i = 0; i < chan->numgangports; i++) {
+		host1x_syncpt_free(chan->mw_ack_sp[i]);
+		host1x_syncpt_free(chan->frame_start_sp[i]);
+	}
+}
+
 static void tegra_channel_cleanup(struct tegra_vi_channel *chan)
 {
 	v4l2_ctrl_handler_free(&chan->ctrl_handler);
 	media_entity_cleanup(&chan->video.entity);
-	host1x_syncpt_free(chan->mw_ack_sp);
-	host1x_syncpt_free(chan->frame_start_sp);
+	tegra_channel_host1x_syncpts_free(chan);
 	mutex_destroy(&chan->video_lock);
 }
 
@@ -1115,11 +1134,46 @@ void tegra_channels_cleanup(struct tegra_vi *vi)
 	}
 }
 
+static int tegra_channel_host1x_syncpt_init(struct tegra_vi_channel *chan)
+{
+	struct tegra_vi *vi = chan->vi;
+	unsigned long flags = HOST1X_SYNCPT_CLIENT_MANAGED;
+	struct host1x_syncpt *fs_sp;
+	struct host1x_syncpt *mw_sp;
+	int ret, i;
+
+	for (i = 0; i < chan->numgangports; i++) {
+		fs_sp = host1x_syncpt_request(&vi->client, flags);
+		if (!fs_sp) {
+			dev_err(vi->dev, "failed to request frame start syncpoint\n");
+			ret = -ENOMEM;
+			goto free_syncpts;
+		}
+
+		mw_sp = host1x_syncpt_request(&vi->client, flags);
+		if (!mw_sp) {
+			dev_err(vi->dev, "failed to request memory ack syncpoint\n");
+			host1x_syncpt_free(fs_sp);
+			ret = -ENOMEM;
+			goto free_syncpts;
+		}
+
+		chan->frame_start_sp[i] = fs_sp;
+		chan->mw_ack_sp[i] = mw_sp;
+		spin_lock_init(&chan->sp_incr_lock[i]);
+	}
+
+	return 0;
+
+free_syncpts:
+	tegra_channel_host1x_syncpts_free(chan);
+	return ret;
+}
+
 static int tegra_channel_init(struct tegra_vi_channel *chan)
 {
 	struct tegra_vi *vi = chan->vi;
 	struct tegra_video_device *vid = dev_get_drvdata(vi->client.host);
-	unsigned long flags = HOST1X_SYNCPT_CLIENT_MANAGED;
 	int ret;
 
 	mutex_init(&chan->video_lock);
@@ -1127,7 +1181,6 @@ static int tegra_channel_init(struct tegra_vi_channel *chan)
 	INIT_LIST_HEAD(&chan->done);
 	spin_lock_init(&chan->start_lock);
 	spin_lock_init(&chan->done_lock);
-	spin_lock_init(&chan->sp_incr_lock);
 	init_waitqueue_head(&chan->start_wait);
 	init_waitqueue_head(&chan->done_wait);
 
@@ -1142,18 +1195,9 @@ static int tegra_channel_init(struct tegra_vi_channel *chan)
 	chan->format.sizeimage = chan->format.bytesperline * TEGRA_DEF_HEIGHT;
 	tegra_channel_fmt_align(chan, &chan->format, chan->fmtinfo->bpp);
 
-	chan->frame_start_sp = host1x_syncpt_request(&vi->client, flags);
-	if (!chan->frame_start_sp) {
-		dev_err(vi->dev, "failed to request frame start syncpoint\n");
-		return -ENOMEM;
-	}
-
-	chan->mw_ack_sp = host1x_syncpt_request(&vi->client, flags);
-	if (!chan->mw_ack_sp) {
-		dev_err(vi->dev, "failed to request memory ack syncpoint\n");
-		ret = -ENOMEM;
-		goto free_fs_syncpt;
-	}
+	ret = tegra_channel_host1x_syncpt_init(chan);
+	if (ret)
+		return ret;
 
 	/* initialize the media entity */
 	chan->pad.flags = MEDIA_PAD_FL_SINK;
@@ -1161,7 +1205,7 @@ static int tegra_channel_init(struct tegra_vi_channel *chan)
 	if (ret < 0) {
 		dev_err(vi->dev,
 			"failed to initialize media entity: %d\n", ret);
-		goto free_mw_ack_syncpt;
+		goto free_syncpts;
 	}
 
 	ret = v4l2_ctrl_handler_init(&chan->ctrl_handler, MAX_CID_CONTROLS);
@@ -1177,7 +1221,7 @@ static int tegra_channel_init(struct tegra_vi_channel *chan)
 	chan->video.release = video_device_release_empty;
 	chan->video.queue = &chan->queue;
 	snprintf(chan->video.name, sizeof(chan->video.name), "%s-%s-%u",
-		 dev_name(vi->dev), "output", chan->portno);
+		 dev_name(vi->dev), "output", chan->portnos[0]);
 	chan->video.vfl_type = VFL_TYPE_VIDEO;
 	chan->video.vfl_dir = VFL_DIR_RX;
 	chan->video.ioctl_ops = &tegra_channel_ioctl_ops;
@@ -1213,17 +1257,16 @@ static int tegra_channel_init(struct tegra_vi_channel *chan)
 	v4l2_ctrl_handler_free(&chan->ctrl_handler);
 cleanup_media:
 	media_entity_cleanup(&chan->video.entity);
-free_mw_ack_syncpt:
-	host1x_syncpt_free(chan->mw_ack_sp);
-free_fs_syncpt:
-	host1x_syncpt_free(chan->frame_start_sp);
+free_syncpts:
+	tegra_channel_host1x_syncpts_free(chan);
 	return ret;
 }
 
 static int tegra_vi_channel_alloc(struct tegra_vi *vi, unsigned int port_num,
-				  struct device_node *node)
+				  struct device_node *node, unsigned int lanes)
 {
 	struct tegra_vi_channel *chan;
+	unsigned int i;
 
 	/*
 	 * Do not use devm_kzalloc as memory is freed immediately
@@ -1236,7 +1279,20 @@ static int tegra_vi_channel_alloc(struct tegra_vi *vi, unsigned int port_num,
 		return -ENOMEM;
 
 	chan->vi = vi;
-	chan->portno = port_num;
+	chan->portnos[0] = port_num;
+	/*
+	 * For data lanes more than maximum csi lanes per brick, multiple of
+	 * x4 ports are used simultaneously for capture.
+	 */
+	if (lanes <= CSI_LANES_PER_BRICK)
+		chan->totalports = 1;
+	else
+		chan->totalports = lanes / CSI_LANES_PER_BRICK;
+	chan->numgangports = chan->totalports;
+
+	for (i = 1; i < chan->totalports; i++)
+		chan->portnos[i] = chan->portnos[0] + i * CSI_PORTS_PER_BRICK;
+
 	chan->of_node = node;
 	list_add_tail(&chan->list, &vi->vi_chans);
 
@@ -1250,7 +1306,8 @@ static int tegra_vi_tpg_channels_alloc(struct tegra_vi *vi)
 	int ret;
 
 	for (port_num = 0; port_num < nchannels; port_num++) {
-		ret = tegra_vi_channel_alloc(vi, port_num, vi->dev->of_node);
+		ret = tegra_vi_channel_alloc(vi, port_num,
+					     vi->dev->of_node, 2);
 		if (ret < 0)
 			return ret;
 	}
@@ -1265,6 +1322,9 @@ static int tegra_vi_channels_alloc(struct tegra_vi *vi)
 	struct device_node *ports;
 	struct device_node *port;
 	unsigned int port_num;
+	struct device_node *parent;
+	struct v4l2_fwnode_endpoint v4l2_ep = { .bus_type = 0 };
+	unsigned int lanes;
 	int ret = 0;
 
 	ports = of_get_child_by_name(node, "ports");
@@ -1291,8 +1351,21 @@ static int tegra_vi_channels_alloc(struct tegra_vi *vi)
 		if (!ep)
 			continue;
 
+		parent = of_graph_get_remote_port_parent(ep);
+		of_node_put(ep);
+		if (!parent)
+			continue;
+
+		ep = of_graph_get_endpoint_by_regs(parent, 0, 0);
+		of_node_put(parent);
+		ret = v4l2_fwnode_endpoint_parse(of_fwnode_handle(ep),
+						 &v4l2_ep);
 		of_node_put(ep);
-		ret = tegra_vi_channel_alloc(vi, port_num, port);
+		if (ret)
+			continue;
+
+		lanes = v4l2_ep.bus.mipi_csi2.num_data_lanes;
+		ret = tegra_vi_channel_alloc(vi, port_num, port, lanes);
 		if (ret < 0) {
 			of_node_put(port);
 			goto cleanup;
@@ -1314,7 +1387,7 @@ static int tegra_vi_channels_init(struct tegra_vi *vi)
 		if (ret < 0) {
 			dev_err(vi->dev,
 				"failed to initialize channel-%d: %d\n",
-				chan->portno, ret);
+				chan->portnos[0], ret);
 			goto cleanup;
 		}
 	}
@@ -1761,7 +1834,8 @@ static int tegra_vi_graph_init(struct tegra_vi *vi)
 	 * next channels.
 	 */
 	list_for_each_entry(chan, &vi->vi_chans, list) {
-		remote = fwnode_graph_get_remote_node(fwnode, chan->portno, 0);
+		remote = fwnode_graph_get_remote_node(fwnode, chan->portnos[0],
+						      0);
 		if (!remote)
 			continue;
 
@@ -1776,7 +1850,7 @@ static int tegra_vi_graph_init(struct tegra_vi *vi)
 		if (ret < 0) {
 			dev_err(vi->dev,
 				"failed to register channel %d notifier: %d\n",
-				chan->portno, ret);
+				chan->portnos[0], ret);
 			v4l2_async_notifier_cleanup(&chan->notifier);
 		}
 	}
@@ -1827,11 +1901,14 @@ static int tegra_vi_init(struct host1x_client *client)
 	if (!IS_ENABLED(CONFIG_VIDEO_TEGRA_TPG)) {
 		ret = tegra_vi_graph_init(vi);
 		if (ret < 0)
-			goto free_chans;
+			goto cleanup_chans;
 	}
 
 	return 0;
 
+cleanup_chans:
+	list_for_each_entry(chan, &vi->vi_chans, list)
+		tegra_channel_cleanup(chan);
 free_chans:
 	list_for_each_entry_safe(chan, tmp, &vi->vi_chans, list) {
 		list_del(&chan->list);

drivers/staging/media/tegra-video/vi.h

@@ -21,6 +21,8 @@
 #include <media/v4l2-subdev.h>
 #include <media/videobuf2-v4l2.h>
 
+#include "csi.h"
+
 #define TEGRA_MIN_WIDTH		32U
 #define TEGRA_MAX_WIDTH		32768U
 #define TEGRA_MIN_HEIGHT	32U
@@ -31,6 +33,7 @@
 #define TEGRA_IMAGE_FORMAT_DEF	32
 
 #define MAX_FORMAT_NUM		64
+#define SURFACE_ALIGN_BYTES	64
 
 enum tegra_vi_pg_mode {
 	TEGRA_VI_PG_DISABLED = 0,
@@ -151,7 +154,9 @@ struct tegra_vi_graph_entity {
  * @done: list of capture done queued buffers
  * @done_lock: protects the capture done queue list
  *
- * @portno: VI channel port number
+ * @portnos: VI channel port numbers
+ * @totalports: total number of ports used for this channel
+ * @numgangports: number of ports combined together as a gang for capture
  * @of_node: device node of VI channel
  *
  * @ctrl_handler: V4L2 control handler of this video channel
@@ -168,10 +173,10 @@ struct tegra_vi_channel {
 	struct media_pad pad;
 
 	struct tegra_vi *vi;
-	struct host1x_syncpt *frame_start_sp;
-	struct host1x_syncpt *mw_ack_sp;
+	struct host1x_syncpt *frame_start_sp[GANG_PORTS_MAX];
+	struct host1x_syncpt *mw_ack_sp[GANG_PORTS_MAX];
 	/* protects the cpu syncpoint increment */
-	spinlock_t sp_incr_lock;
+	spinlock_t sp_incr_lock[GANG_PORTS_MAX];
 
 	struct task_struct *kthread_start_capture;
 	wait_queue_head_t start_wait;
@@ -190,7 +195,9 @@ struct tegra_vi_channel {
 	/* protects the capture done queue list */
 	spinlock_t done_lock;
 
-	unsigned char portno;
+	unsigned char portnos[GANG_PORTS_MAX];
+	u8 totalports;
+	u8 numgangports;
 	struct device_node *of_node;
 
 	struct v4l2_ctrl_handler ctrl_handler;
@@ -216,7 +223,7 @@ struct tegra_channel_buffer {
 	struct list_head queue;
 	struct tegra_vi_channel *chan;
 	dma_addr_t addr;
-	u32 mw_ack_sp_thresh;
+	u32 mw_ack_sp_thresh[GANG_PORTS_MAX];
 };
 
 /*