[v4,1/9] ethdev: introduce dump API

diff --git a/doc/guides/rel_notes/release_22_03.rst b/doc/guides/rel_notes/release_22_03.rst
index 0f1d3adaf2..10ac807e1c 100644
--- a/doc/guides/rel_notes/release_22_03.rst
+++ b/doc/guides/rel_notes/release_22_03.rst
@@ -80,6 +80,13 @@  New Features
   New APIs, ``rte_eth_dev_priority_flow_ctrl_queue_info_get()`` and
   ``rte_eth_dev_priority_flow_ctrl_queue_configure()``, was added.
 
+* **Added the private dump API, for query private info from device.**
+
+  Added the private dump API which provides querying private info from device.
+  There exists many private properties in different PMD drivers. The
+  information of these properties is important for debug. As the information
+  is private, the new API is introduced.
+
 * **Updated AF_XDP PMD**
 
   * Added support for libxdp >=v1.2.2.
diff --git a/lib/ethdev/ethdev_driver.h b/lib/ethdev/ethdev_driver.h
index 76a3975c1b..617b450d57 100644
--- a/lib/ethdev/ethdev_driver.h
+++ b/lib/ethdev/ethdev_driver.h
@@ -1045,6 +1045,25 @@  typedef int (*eth_ip_reassembly_conf_get_t)(struct rte_eth_dev *dev,
 typedef int (*eth_ip_reassembly_conf_set_t)(struct rte_eth_dev *dev,
 		const struct rte_eth_ip_reassembly_params *conf);
 
+/**
+ * @internal
+ * Dump private info from device to a file.
+ *
+ * @param dev
+ *   Port (ethdev) handle.
+ * @param file
+ *   A pointer to a file for output.
+ *
+ * @return
+ *   Negative value on error, 0 on success.
+ *
+ * @retval 0
+ *   Success
+ * @retval -EINVAL
+ *   Invalid file
+ */
+typedef int (*eth_dev_priv_dump_t)(struct rte_eth_dev *dev, FILE *file);
+
 /**
  * @internal A structure containing the functions exported by an Ethernet driver.
  */
@@ -1252,6 +1271,9 @@  struct eth_dev_ops {
 	eth_ip_reassembly_conf_get_t ip_reassembly_conf_get;
 	/** Set IP reassembly configuration */
 	eth_ip_reassembly_conf_set_t ip_reassembly_conf_set;
+
+	/** Dump private info from device */
+	eth_dev_priv_dump_t eth_dev_priv_dump;
 };
 
 /**
diff --git a/lib/ethdev/rte_ethdev.c b/lib/ethdev/rte_ethdev.c
index c95b3cd3db..2a479bea21 100644
--- a/lib/ethdev/rte_ethdev.c
+++ b/lib/ethdev/rte_ethdev.c
@@ -6750,6 +6750,23 @@  rte_eth_ip_reassembly_dynfield_register(int *field_offset, int *flag_offset)
 	return 0;
 }
 
+int
+rte_eth_dev_priv_dump(uint16_t port_id, FILE *file)
+{
+	struct rte_eth_dev *dev;
+
+	RTE_ETH_VALID_PORTID_OR_ERR_RET(port_id, -ENODEV);
+	dev = &rte_eth_devices[port_id];
+
+	if (file == NULL) {
+		RTE_ETHDEV_LOG(ERR, "Invalid file (NULL)\n");
+		return -EINVAL;
+	}
+
+	RTE_FUNC_PTR_OR_ERR_RET(*dev->dev_ops->eth_dev_priv_dump, -ENOTSUP);
+	return eth_err(port_id, (*dev->dev_ops->eth_dev_priv_dump)(dev, file));
+}
+
 RTE_LOG_REGISTER_DEFAULT(rte_eth_dev_logtype, INFO);
 
 RTE_INIT(ethdev_init_telemetry)
diff --git a/lib/ethdev/rte_ethdev.h b/lib/ethdev/rte_ethdev.h
index f554e716bc..3439b04119 100644
--- a/lib/ethdev/rte_ethdev.h
+++ b/lib/ethdev/rte_ethdev.h
@@ -5432,6 +5432,26 @@  typedef struct {
 	uint16_t nb_frags;
 } rte_eth_ip_reassembly_dynfield_t;
 
+/**
+ * @warning
+ * @b EXPERIMENTAL: this API may change, or be removed, without prior notice
+ *
+ * Dump private info from device to a file. Provided data and the order depends
+ * on the PMD.
+ *
+ * @param port_id
+ *   The port identifier of the Ethernet device.
+ * @param file
+ *   A pointer to a file for output.
+ * @return
+ *   - (0) on success.
+ *   - (-ENODEV) if *port_id* is invalid.
+ *   - (-EINVAL) if null file.
+ *   - (-ENOTSUP) if the device does not support this function.
+ *   - (-EIO) if device is removed.
+ */
+__rte_experimental
+int rte_eth_dev_priv_dump(uint16_t port_id, FILE *file);
 
 #include <rte_ethdev_core.h>
 
diff --git a/lib/ethdev/version.map b/lib/ethdev/version.map
index 1ca7ec33ee..fb82c8bf53 100644
--- a/lib/ethdev/version.map
+++ b/lib/ethdev/version.map
@@ -263,6 +263,7 @@  EXPERIMENTAL {
 	rte_eth_ip_reassembly_capability_get;
 	rte_eth_ip_reassembly_conf_get;
 	rte_eth_ip_reassembly_conf_set;
+	rte_eth_dev_priv_dump;
 };
 
 INTERNAL {