drm/amd/display: Try RGB before YCbCr 4:4:4 in stream validationgrafted

amdgpu_dm_create_validate_stream_for_sink() walks encoding_order[] and
uses the first encoding that validates. YCbCr 4:4:4 is listed before
RGB, so an HDMI sink that advertises 4:4:4 gets YCbCr 4:4:4 whenever the
"color format" property is left at AUTO, even though RGB fits the same
link.

That contradicts the documented AUTO behaviour for HDMI in enum
drm_connector_color_format (RGB, falling back to YCbCr 4:2:0 only when
the bandwidth is not available or the mode is 4:2:0-only), which the
amdgpu implementation of the property also describes. It also leaves
the "Broadcast RGB" property without effect on such sinks, since the
quantization range it selects only applies to RGB output.

Try RGB first. The mask still holds every encoding the sink supports,
so a mode that cannot carry RGB falls back exactly as before.

For reference, v7.2 picked RGB here unless YCbCr 4:4:4 was forced
through debugfs, while earlier kernels picked YCbCr 4:4:4 for any HDMI
sink that advertised it.

Fixes: 0b0ff65d3ca1 ("drm/amd/display: Refactor stream validation")
Suggested-by: Adolfo Rodrigues <adolfotregosa@gmail.com>
Assisted-by: Claude Code:claude-fable-5-1
Signed-off-by: Adrian Betschart <adrian.betschart@cinemaone.ch>
Reviewed-by: Fangzhi Zuo <jerry.zuo@amd.com>
Tested-by: Adolfo Rodrigues <adolfotregosa@gmail.com>
Tested-by: Daniel Wheeler <daniel.wheeler@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
(cherry picked from commit 7de432bc753133764dc40d37f9388da56de251e7)

1 files changed, 763 insertions, 0 deletions

diff --git a/drivers/thunderbolt/dma_test.c b/drivers/thunderbolt/dma_test.c
new file mode 100644
index 000000000..519c67678
--- /dev/null
+++ b/drivers/thunderbolt/dma_test.c
@@ -0,0 +1,763 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * DMA traffic test driver
+ *
+ * Copyright (C) 2020, Intel Corporation
+ * Authors: Isaac Hazan <isaac.hazan@intel.com>
+ *	    Mika Westerberg <mika.westerberg@linux.intel.com>
+ */
+
+#include <linux/completion.h>
+#include <linux/debugfs.h>
+#include <linux/module.h>
+#include <linux/sizes.h>
+#include <linux/thunderbolt.h>
+
+#define DMA_TEST_TX_RING_SIZE		64
+#define DMA_TEST_RX_RING_SIZE		256
+#define DMA_TEST_FRAME_SIZE		SZ_4K
+#define DMA_TEST_DATA_PATTERN		0x0123456789abcdefLL
+#define DMA_TEST_MAX_PACKETS		1000
+
+enum dma_test_frame_pdf {
+	DMA_TEST_PDF_FRAME_START = 1,
+	DMA_TEST_PDF_FRAME_END,
+};
+
+struct dma_test_frame {
+	struct dma_test *dma_test;
+	void *data;
+	struct ring_frame frame;
+};
+
+enum dma_test_test_error {
+	DMA_TEST_NO_ERROR,
+	DMA_TEST_INTERRUPTED,
+	DMA_TEST_BUFFER_ERROR,
+	DMA_TEST_DMA_ERROR,
+	DMA_TEST_CONFIG_ERROR,
+	DMA_TEST_SPEED_ERROR,
+	DMA_TEST_WIDTH_ERROR,
+	DMA_TEST_BONDING_ERROR,
+	DMA_TEST_PACKET_ERROR,
+};
+
+static const char * const dma_test_error_names[] = {
+	[DMA_TEST_NO_ERROR] = "no errors",
+	[DMA_TEST_INTERRUPTED] = "interrupted by signal",
+	[DMA_TEST_BUFFER_ERROR] = "no memory for packet buffers",
+	[DMA_TEST_DMA_ERROR] = "DMA ring setup failed",
+	[DMA_TEST_CONFIG_ERROR] = "configuration is not valid",
+	[DMA_TEST_SPEED_ERROR] = "unexpected link speed",
+	[DMA_TEST_WIDTH_ERROR] = "unexpected link width",
+	[DMA_TEST_BONDING_ERROR] = "lane bonding configuration error",
+	[DMA_TEST_PACKET_ERROR] = "packet check failed",
+};
+
+enum dma_test_result {
+	DMA_TEST_NOT_RUN,
+	DMA_TEST_SUCCESS,
+	DMA_TEST_FAIL,
+};
+
+static const char * const dma_test_result_names[] = {
+	[DMA_TEST_NOT_RUN] = "not run",
+	[DMA_TEST_SUCCESS] = "success",
+	[DMA_TEST_FAIL] = "failed",
+};
+
+/**
+ * struct dma_test - DMA test device driver private data
+ * @svc: XDomain service the driver is bound to
+ * @xd: XDomain the service belongs to
+ * @rx_ring: Software ring holding RX frames
+ * @rx_hopid: HopID used for receiving frames
+ * @tx_ring: Software ring holding TX frames
+ * @tx_hopid: HopID used for sending fames
+ * @packets_to_send: Number of packets to send
+ * @packets_to_receive: Number of packets to receive
+ * @packets_sent: Actual number of packets sent
+ * @packets_received: Actual number of packets received
+ * @link_speed: Expected link speed (Gb/s), %0 to use whatever is negotiated
+ * @link_width: Expected link width (Gb/s), %0 to use whatever is negotiated
+ * @crc_errors: Number of CRC errors during the test run
+ * @buffer_overflow_errors: Number of buffer overflow errors during the test
+ *			    run
+ * @result: Result of the last run
+ * @error_code: Error code of the last run
+ * @complete: Used to wait for the Rx to complete
+ * @lock: Lock serializing access to this structure
+ */
+struct dma_test {
+	const struct tb_service *svc;
+	struct tb_xdomain *xd;
+	struct tb_ring *rx_ring;
+	int rx_hopid;
+	struct tb_ring *tx_ring;
+	int tx_hopid;
+	unsigned int packets_to_send;
+	unsigned int packets_to_receive;
+	unsigned int packets_sent;
+	unsigned int packets_received;
+	unsigned int link_speed;
+	enum tb_link_width link_width;
+	unsigned int crc_errors;
+	unsigned int buffer_overflow_errors;
+	enum dma_test_result result;
+	enum dma_test_test_error error_code;
+	struct completion complete;
+	struct mutex lock;
+};
+
+/* DMA test property directory UUID: 3188cd10-6523-4a5a-a682-fdca07a248d8 */
+static const uuid_t dma_test_dir_uuid =
+	UUID_INIT(0x3188cd10, 0x6523, 0x4a5a,
+		  0xa6, 0x82, 0xfd, 0xca, 0x07, 0xa2, 0x48, 0xd8);
+
+static struct tb_property_dir *dma_test_dir;
+static void *dma_test_pattern;
+
+static void dma_test_free_rings(struct dma_test *dt)
+{
+	if (dt->rx_ring) {
+		tb_xdomain_release_in_hopid(dt->xd, dt->rx_hopid);
+		tb_ring_free(dt->rx_ring);
+		dt->rx_ring = NULL;
+	}
+	if (dt->tx_ring) {
+		tb_xdomain_release_out_hopid(dt->xd, dt->tx_hopid);
+		tb_ring_free(dt->tx_ring);
+		dt->tx_ring = NULL;
+	}
+}
+
+static int dma_test_start_rings(struct dma_test *dt)
+{
+	unsigned int flags = RING_FLAG_FRAME;
+	struct tb_xdomain *xd = dt->xd;
+	int ret, e2e_tx_hop = 0;
+	struct tb_ring *ring;
+
+	/*
+	 * If we are both sender and receiver (traffic goes over a
+	 * special loopback dongle) enable E2E flow control. This avoids
+	 * losing packets.
+	 */
+	if (dt->packets_to_send && dt->packets_to_receive)
+		flags |= RING_FLAG_E2E;
+
+	if (dt->packets_to_send) {
+		ring = tb_ring_alloc_tx(xd->tb->nhi, -1, DMA_TEST_TX_RING_SIZE,
+					flags);
+		if (!ring)
+			return -ENOMEM;
+
+		dt->tx_ring = ring;
+		e2e_tx_hop = ring->hop;
+
+		tb_ring_throttling(ring, 128000);
+
+		ret = tb_xdomain_alloc_out_hopid(xd, -1);
+		if (ret < 0) {
+			dma_test_free_rings(dt);
+			return ret;
+		}
+
+		dt->tx_hopid = ret;
+
+	}
+
+	if (dt->packets_to_receive) {
+		u16 sof_mask, eof_mask;
+
+		sof_mask = BIT(DMA_TEST_PDF_FRAME_START);
+		eof_mask = BIT(DMA_TEST_PDF_FRAME_END);
+
+		ring = tb_ring_alloc_rx(xd->tb->nhi, -1, DMA_TEST_RX_RING_SIZE,
+					flags, e2e_tx_hop, sof_mask, eof_mask,
+					NULL, NULL);
+		if (!ring) {
+			dma_test_free_rings(dt);
+			return -ENOMEM;
+		}
+
+		dt->rx_ring = ring;
+
+		tb_ring_throttling(ring, 128000);
+
+		ret = tb_xdomain_alloc_in_hopid(xd, -1);
+		if (ret < 0) {
+			dma_test_free_rings(dt);
+			return ret;
+		}
+
+		dt->rx_hopid = ret;
+	}
+
+	ret = tb_xdomain_enable_paths(dt->xd, dt->tx_hopid,
+				      dt->tx_ring ? dt->tx_ring->hop : -1,
+				      dt->rx_hopid,
+				      dt->rx_ring ? dt->rx_ring->hop : -1);
+	if (ret) {
+		dma_test_free_rings(dt);
+		return ret;
+	}
+
+	if (dt->tx_ring)
+		tb_ring_start(dt->tx_ring);
+	if (dt->rx_ring)
+		tb_ring_start(dt->rx_ring);
+
+	return 0;
+}
+
+static void dma_test_stop_rings(struct dma_test *dt)
+{
+	int ret;
+
+	if (dt->rx_ring)
+		tb_ring_stop(dt->rx_ring);
+	if (dt->tx_ring)
+		tb_ring_stop(dt->tx_ring);
+
+	ret = tb_xdomain_disable_paths(dt->xd, dt->tx_hopid,
+				       dt->tx_ring ? dt->tx_ring->hop : -1,
+				       dt->rx_hopid,
+				       dt->rx_ring ? dt->rx_ring->hop : -1);
+	if (ret)
+		dev_warn(&dt->svc->dev, "failed to disable DMA paths\n");
+
+	dma_test_free_rings(dt);
+}
+
+static void dma_test_rx_callback(struct tb_ring *ring, struct ring_frame *frame,
+				 bool canceled)
+{
+	struct dma_test_frame *tf = container_of(frame, typeof(*tf), frame);
+	struct dma_test *dt = tf->dma_test;
+	struct device *dma_dev = tb_ring_dma_device(dt->rx_ring);
+
+	dma_unmap_single(dma_dev, tf->frame.buffer_phy, DMA_TEST_FRAME_SIZE,
+			 DMA_FROM_DEVICE);
+	kfree(tf->data);
+
+	if (canceled) {
+		kfree(tf);
+		return;
+	}
+
+	dt->packets_received++;
+	dev_dbg(&dt->svc->dev, "packet %u/%u received\n", dt->packets_received,
+		dt->packets_to_receive);
+
+	if (tf->frame.flags & RING_DESC_CRC_ERROR)
+		dt->crc_errors++;
+	if (tf->frame.flags & RING_DESC_BUFFER_OVERRUN)
+		dt->buffer_overflow_errors++;
+
+	kfree(tf);
+
+	if (dt->packets_received == dt->packets_to_receive)
+		complete(&dt->complete);
+}
+
+static int dma_test_submit_rx(struct dma_test *dt, size_t npackets)
+{
+	struct device *dma_dev = tb_ring_dma_device(dt->rx_ring);
+	int i;
+
+	for (i = 0; i < npackets; i++) {
+		struct dma_test_frame *tf;
+		dma_addr_t dma_addr;
+
+		tf = kzalloc_obj(*tf);
+		if (!tf)
+			return -ENOMEM;
+
+		tf->data = kzalloc(DMA_TEST_FRAME_SIZE, GFP_KERNEL);
+		if (!tf->data) {
+			kfree(tf);
+			return -ENOMEM;
+		}
+
+		dma_addr = dma_map_single(dma_dev, tf->data, DMA_TEST_FRAME_SIZE,
+					  DMA_FROM_DEVICE);
+		if (dma_mapping_error(dma_dev, dma_addr)) {
+			kfree(tf->data);
+			kfree(tf);
+			return -ENOMEM;
+		}
+
+		tf->frame.buffer_phy = dma_addr;
+		tf->frame.callback = dma_test_rx_callback;
+		tf->dma_test = dt;
+		INIT_LIST_HEAD(&tf->frame.list);
+
+		tb_ring_rx(dt->rx_ring, &tf->frame);
+	}
+
+	return 0;
+}
+
+static void dma_test_tx_callback(struct tb_ring *ring, struct ring_frame *frame,
+				 bool canceled)
+{
+	struct dma_test_frame *tf = container_of(frame, typeof(*tf), frame);
+	struct dma_test *dt = tf->dma_test;
+	struct device *dma_dev = tb_ring_dma_device(dt->tx_ring);
+
+	dma_unmap_single(dma_dev, tf->frame.buffer_phy, DMA_TEST_FRAME_SIZE,
+			 DMA_TO_DEVICE);
+	kfree(tf->data);
+	kfree(tf);
+}
+
+static int dma_test_submit_tx(struct dma_test *dt, size_t npackets)
+{
+	struct device *dma_dev = tb_ring_dma_device(dt->tx_ring);
+	int i;
+
+	for (i = 0; i < npackets; i++) {
+		struct dma_test_frame *tf;
+		dma_addr_t dma_addr;
+
+		tf = kzalloc_obj(*tf);
+		if (!tf)
+			return -ENOMEM;
+
+		tf->frame.size = 0; /* means 4096 */
+		tf->dma_test = dt;
+
+		tf->data = kmemdup(dma_test_pattern, DMA_TEST_FRAME_SIZE, GFP_KERNEL);
+		if (!tf->data) {
+			kfree(tf);
+			return -ENOMEM;
+		}
+
+		dma_addr = dma_map_single(dma_dev, tf->data, DMA_TEST_FRAME_SIZE,
+					  DMA_TO_DEVICE);
+		if (dma_mapping_error(dma_dev, dma_addr)) {
+			kfree(tf->data);
+			kfree(tf);
+			return -ENOMEM;
+		}
+
+		tf->frame.buffer_phy = dma_addr;
+		tf->frame.callback = dma_test_tx_callback;
+		tf->frame.sof = DMA_TEST_PDF_FRAME_START;
+		tf->frame.eof = DMA_TEST_PDF_FRAME_END;
+		INIT_LIST_HEAD(&tf->frame.list);
+
+		dt->packets_sent++;
+		dev_dbg(&dt->svc->dev, "packet %u/%u sent\n", dt->packets_sent,
+			dt->packets_to_send);
+
+		tb_ring_tx(dt->tx_ring, &tf->frame);
+	}
+
+	return 0;
+}
+
+#define DMA_TEST_DEBUGFS_ATTR(__fops, __get, __validate, __set)	\
+static int __fops ## _show(void *data, u64 *val)		\
+{								\
+	struct tb_service *svc = data;				\
+	struct dma_test *dt = tb_service_get_drvdata(svc);	\
+	int ret;						\
+								\
+	ret = mutex_lock_interruptible(&dt->lock);		\
+	if (ret)						\
+		return ret;					\
+	__get(dt, val);						\
+	mutex_unlock(&dt->lock);				\
+	return 0;						\
+}								\
+static int __fops ## _store(void *data, u64 val)		\
+{								\
+	struct tb_service *svc = data;				\
+	struct dma_test *dt = tb_service_get_drvdata(svc);	\
+	int ret;						\
+								\
+	ret = __validate(val);					\
+	if (ret)						\
+		return ret;					\
+	ret = mutex_lock_interruptible(&dt->lock);		\
+	if (ret)						\
+		return ret;					\
+	__set(dt, val);						\
+	mutex_unlock(&dt->lock);				\
+	return 0;						\
+}								\
+DEFINE_DEBUGFS_ATTRIBUTE(__fops ## _fops, __fops ## _show,	\
+			 __fops ## _store, "%llu\n")
+
+static void lanes_get(const struct dma_test *dt, u64 *val)
+{
+	*val = dt->link_width;
+}
+
+static int lanes_validate(u64 val)
+{
+	return val > 2 ? -EINVAL : 0;
+}
+
+static void lanes_set(struct dma_test *dt, u64 val)
+{
+	dt->link_width = val;
+}
+DMA_TEST_DEBUGFS_ATTR(lanes, lanes_get, lanes_validate, lanes_set);
+
+static void speed_get(const struct dma_test *dt, u64 *val)
+{
+	*val = dt->link_speed;
+}
+
+static int speed_validate(u64 val)
+{
+	switch (val) {
+	case 40:
+	case 20:
+	case 10:
+	case 0:
+		return 0;
+	default:
+		return -EINVAL;
+	}
+}
+
+static void speed_set(struct dma_test *dt, u64 val)
+{
+	dt->link_speed = val;
+}
+DMA_TEST_DEBUGFS_ATTR(speed, speed_get, speed_validate, speed_set);
+
+static void packets_to_receive_get(const struct dma_test *dt, u64 *val)
+{
+	*val = dt->packets_to_receive;
+}
+
+static int packets_to_receive_validate(u64 val)
+{
+	return val > DMA_TEST_MAX_PACKETS ? -EINVAL : 0;
+}
+
+static void packets_to_receive_set(struct dma_test *dt, u64 val)
+{
+	dt->packets_to_receive = val;
+}
+DMA_TEST_DEBUGFS_ATTR(packets_to_receive, packets_to_receive_get,
+		      packets_to_receive_validate, packets_to_receive_set);
+
+static void packets_to_send_get(const struct dma_test *dt, u64 *val)
+{
+	*val = dt->packets_to_send;
+}
+
+static int packets_to_send_validate(u64 val)
+{
+	return val > DMA_TEST_MAX_PACKETS ? -EINVAL : 0;
+}
+
+static void packets_to_send_set(struct dma_test *dt, u64 val)
+{
+	dt->packets_to_send = val;
+}
+DMA_TEST_DEBUGFS_ATTR(packets_to_send, packets_to_send_get,
+		      packets_to_send_validate, packets_to_send_set);
+
+static int dma_test_set_bonding(struct dma_test *dt)
+{
+	switch (dt->link_width) {
+	case TB_LINK_WIDTH_DUAL:
+		return tb_xdomain_lane_bonding_enable(dt->xd);
+	case TB_LINK_WIDTH_SINGLE:
+		tb_xdomain_lane_bonding_disable(dt->xd);
+		fallthrough;
+	default:
+		return 0;
+	}
+}
+
+static bool dma_test_validate_config(struct dma_test *dt)
+{
+	if (!dt->packets_to_send && !dt->packets_to_receive)
+		return false;
+	if (dt->packets_to_send && dt->packets_to_receive &&
+	    dt->packets_to_send != dt->packets_to_receive)
+		return false;
+	return true;
+}
+
+static void dma_test_check_errors(struct dma_test *dt, int ret)
+{
+	if (!dt->error_code) {
+		if (dt->link_speed && dt->xd->link_speed != dt->link_speed) {
+			dt->error_code = DMA_TEST_SPEED_ERROR;
+		} else if (dt->link_width && dt->link_width != dt->xd->link_width) {
+			dt->error_code = DMA_TEST_WIDTH_ERROR;
+		} else if (dt->packets_to_send != dt->packets_sent ||
+			 dt->packets_to_receive != dt->packets_received ||
+			 dt->crc_errors || dt->buffer_overflow_errors) {
+			dt->error_code = DMA_TEST_PACKET_ERROR;
+		} else {
+			return;
+		}
+	}
+
+	dt->result = DMA_TEST_FAIL;
+}
+
+static int test_store(void *data, u64 val)
+{
+	struct tb_service *svc = data;
+	struct dma_test *dt = tb_service_get_drvdata(svc);
+	int ret;
+
+	if (val != 1)
+		return -EINVAL;
+
+	ret = mutex_lock_interruptible(&dt->lock);
+	if (ret)
+		return ret;
+
+	dt->packets_sent = 0;
+	dt->packets_received = 0;
+	dt->crc_errors = 0;
+	dt->buffer_overflow_errors = 0;
+	dt->result = DMA_TEST_SUCCESS;
+	dt->error_code = DMA_TEST_NO_ERROR;
+
+	dev_dbg(&svc->dev, "DMA test starting\n");
+	if (dt->link_speed)
+		dev_dbg(&svc->dev, "link_speed: %u Gb/s\n", dt->link_speed);
+	if (dt->link_width)
+		dev_dbg(&svc->dev, "link_width: %u\n", dt->link_width);
+	dev_dbg(&svc->dev, "packets_to_send: %u\n", dt->packets_to_send);
+	dev_dbg(&svc->dev, "packets_to_receive: %u\n", dt->packets_to_receive);
+
+	if (!dma_test_validate_config(dt)) {
+		dev_err(&svc->dev, "invalid test configuration\n");
+		dt->error_code = DMA_TEST_CONFIG_ERROR;
+		goto out_unlock;
+	}
+
+	ret = dma_test_set_bonding(dt);
+	if (ret) {
+		dev_err(&svc->dev, "failed to set lanes\n");
+		dt->error_code = DMA_TEST_BONDING_ERROR;
+		goto out_unlock;
+	}
+
+	ret = dma_test_start_rings(dt);
+	if (ret) {
+		dev_err(&svc->dev, "failed to enable DMA rings\n");
+		dt->error_code = DMA_TEST_DMA_ERROR;
+		goto out_unlock;
+	}
+
+	if (dt->packets_to_receive) {
+		reinit_completion(&dt->complete);
+		ret = dma_test_submit_rx(dt, dt->packets_to_receive);
+		if (ret) {
+			dev_err(&svc->dev, "failed to submit receive buffers\n");
+			dt->error_code = DMA_TEST_BUFFER_ERROR;
+			goto out_stop;
+		}
+	}
+
+	if (dt->packets_to_send) {
+		ret = dma_test_submit_tx(dt, dt->packets_to_send);
+		if (ret) {
+			dev_err(&svc->dev, "failed to submit transmit buffers\n");
+			dt->error_code = DMA_TEST_BUFFER_ERROR;
+			goto out_stop;
+		}
+	}
+
+	if (dt->packets_to_receive) {
+		ret = wait_for_completion_interruptible(&dt->complete);
+		if (ret) {
+			dt->error_code = DMA_TEST_INTERRUPTED;
+			goto out_stop;
+		}
+	}
+
+out_stop:
+	dma_test_stop_rings(dt);
+out_unlock:
+	dma_test_check_errors(dt, ret);
+	mutex_unlock(&dt->lock);
+
+	dev_dbg(&svc->dev, "DMA test %s\n", dma_test_result_names[dt->result]);
+	return ret;
+}
+DEFINE_DEBUGFS_ATTRIBUTE(test_fops, NULL, test_store, "%llu\n");
+
+static int status_show(struct seq_file *s, void *not_used)
+{
+	struct tb_service *svc = s->private;
+	struct dma_test *dt = tb_service_get_drvdata(svc);
+	int ret;
+
+	ret = mutex_lock_interruptible(&dt->lock);
+	if (ret)
+		return ret;
+
+	seq_printf(s, "result: %s\n", dma_test_result_names[dt->result]);
+	if (dt->result == DMA_TEST_NOT_RUN)
+		goto out_unlock;
+
+	seq_printf(s, "packets received: %u\n", dt->packets_received);
+	seq_printf(s, "packets sent: %u\n", dt->packets_sent);
+	seq_printf(s, "CRC errors: %u\n", dt->crc_errors);
+	seq_printf(s, "buffer overflow errors: %u\n",
+		   dt->buffer_overflow_errors);
+	seq_printf(s, "error: %s\n", dma_test_error_names[dt->error_code]);
+
+out_unlock:
+	mutex_unlock(&dt->lock);
+	return 0;
+}
+DEFINE_SHOW_ATTRIBUTE(status);
+
+static void dma_test_debugfs_init(struct tb_service *svc)
+{
+	struct dentry *debugfs_dir;
+
+	debugfs_dir = debugfs_create_dir("dma_test", svc->debugfs_dir);
+
+	debugfs_create_file("lanes", 0600, debugfs_dir, svc, &lanes_fops);
+	debugfs_create_file("speed", 0600, debugfs_dir, svc, &speed_fops);
+	debugfs_create_file("packets_to_receive", 0600, debugfs_dir, svc,
+			    &packets_to_receive_fops);
+	debugfs_create_file("packets_to_send", 0600, debugfs_dir, svc,
+			    &packets_to_send_fops);
+	debugfs_create_file("status", 0400, debugfs_dir, svc, &status_fops);
+	debugfs_create_file("test", 0200, debugfs_dir, svc, &test_fops);
+}
+
+static int dma_test_probe(struct tb_service *svc)
+{
+	struct tb_xdomain *xd = tb_service_parent(svc);
+	struct dma_test *dt;
+
+	dt = devm_kzalloc(&svc->dev, sizeof(*dt), GFP_KERNEL);
+	if (!dt)
+		return -ENOMEM;
+
+	dt->svc = svc;
+	dt->xd = xd;
+	mutex_init(&dt->lock);
+	init_completion(&dt->complete);
+
+	tb_service_set_drvdata(svc, dt);
+	dma_test_debugfs_init(svc);
+
+	return 0;
+}
+
+static void dma_test_remove(struct tb_service *svc)
+{
+	struct dma_test *dt = tb_service_get_drvdata(svc);
+
+	mutex_lock(&dt->lock);
+	debugfs_lookup_and_remove("dma_test", svc->debugfs_dir);
+	mutex_unlock(&dt->lock);
+}
+
+static int __maybe_unused dma_test_suspend(struct device *dev)
+{
+	/*
+	 * No need to do anything special here. If userspace is writing
+	 * to the test attribute when suspend started, it comes out from
+	 * wait_for_completion_interruptible() with -ERESTARTSYS and the
+	 * DMA test fails tearing down the rings. Once userspace is
+	 * thawed the kernel restarts the write syscall effectively
+	 * re-running the test.
+	 */
+	return 0;
+}
+
+static int __maybe_unused dma_test_resume(struct device *dev)
+{
+	return 0;
+}
+
+static const struct dev_pm_ops dma_test_pm_ops = {
+	SET_SYSTEM_SLEEP_PM_OPS(dma_test_suspend, dma_test_resume)
+};
+
+static const struct tb_service_id dma_test_ids[] = {
+	{ TB_SERVICE("dma_test", 1) },
+	{ }
+};
+MODULE_DEVICE_TABLE(tbsvc, dma_test_ids);
+
+static struct tb_service_driver dma_test_driver = {
+	.driver = {
+		.owner = THIS_MODULE,
+		.name = "thunderbolt_dma_test",
+		.pm = &dma_test_pm_ops,
+	},
+	.probe = dma_test_probe,
+	.remove = dma_test_remove,
+	.id_table = dma_test_ids,
+};
+
+static int __init dma_test_init(void)
+{
+	u64 data_value = DMA_TEST_DATA_PATTERN;
+	int i, ret;
+
+	dma_test_pattern = kmalloc(DMA_TEST_FRAME_SIZE, GFP_KERNEL);
+	if (!dma_test_pattern)
+		return -ENOMEM;
+
+	for (i = 0; i <	DMA_TEST_FRAME_SIZE / sizeof(data_value); i++)
+		((u32 *)dma_test_pattern)[i] = data_value++;
+
+	dma_test_dir = tb_property_create_dir(&dma_test_dir_uuid);
+	if (!dma_test_dir) {
+		ret = -ENOMEM;
+		goto err_free_pattern;
+	}
+
+	tb_property_add_immediate(dma_test_dir, "prtcid", 1);
+	tb_property_add_immediate(dma_test_dir, "prtcvers", 1);
+	tb_property_add_immediate(dma_test_dir, "prtcrevs", 0);
+	tb_property_add_immediate(dma_test_dir, "prtcstns", 0);
+
+	ret = tb_register_property_dir("dma_test", dma_test_dir);
+	if (ret)
+		goto err_free_dir;
+
+	ret = tb_register_service_driver(&dma_test_driver);
+	if (ret)
+		goto err_unregister_dir;
+
+	return 0;
+
+err_unregister_dir:
+	tb_unregister_property_dir("dma_test", dma_test_dir);
+err_free_dir:
+	tb_property_free_dir(dma_test_dir);
+err_free_pattern:
+	kfree(dma_test_pattern);
+
+	return ret;
+}
+module_init(dma_test_init);
+
+static void __exit dma_test_exit(void)
+{
+	tb_unregister_service_driver(&dma_test_driver);
+	tb_unregister_property_dir("dma_test", dma_test_dir);
+	tb_property_free_dir(dma_test_dir);
+	kfree(dma_test_pattern);
+}
+module_exit(dma_test_exit);
+
+MODULE_AUTHOR("Isaac Hazan <isaac.hazan@intel.com>");
+MODULE_AUTHOR("Mika Westerberg <mika.westerberg@linux.intel.com>");
+MODULE_DESCRIPTION("Thunderbolt/USB4 DMA traffic test driver");
+MODULE_LICENSE("GPL v2");