[v8,1/4] ethdev: introduce protocol header API

diff --git a/doc/guides/rel_notes/release_22_11.rst b/doc/guides/rel_notes/release_22_11.rst
index ac67e7e710..141fd9442b 100644
--- a/doc/guides/rel_notes/release_22_11.rst
+++ b/doc/guides/rel_notes/release_22_11.rst
@@ -123,6 +123,11 @@  New Features
   into single event containing ``rte_event_vector``
   whose event type is ``RTE_EVENT_TYPE_CRYPTODEV_VECTOR``.
 
+* **Added protocol header based buffer split.**
+
+  * Added ``rte_eth_buffer_split_get_supported_hdr_ptypes()``, to get supported
+    header protocols of a PMD to split.
+
 
 Removed Items
 -------------
diff --git a/lib/ethdev/ethdev_driver.h b/lib/ethdev/ethdev_driver.h
index 8cd8eb8685..791b264610 100644
--- a/lib/ethdev/ethdev_driver.h
+++ b/lib/ethdev/ethdev_driver.h
@@ -1055,6 +1055,18 @@  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
+ * Get supported header protocols of a PMD to split.
+ *
+ * @param dev
+ *   Ethdev handle of port.
+ *
+ * @return
+ *   An array pointer to store supported protocol headers.
+ */
+typedef const uint32_t *(*eth_buffer_split_supported_hdr_ptypes_get_t)(struct rte_eth_dev *dev);
+
 /**
  * @internal
  * Dump private info from device to a file.
@@ -1302,6 +1314,9 @@  struct eth_dev_ops {
 	/** Set IP reassembly configuration */
 	eth_ip_reassembly_conf_set_t ip_reassembly_conf_set;
 
+	/** Get supported header ptypes to split */
+	eth_buffer_split_supported_hdr_ptypes_get_t buffer_split_supported_hdr_ptypes_get;
+
 	/** 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 2821770e2d..ee3b490889 100644
--- a/lib/ethdev/rte_ethdev.c
+++ b/lib/ethdev/rte_ethdev.c
@@ -6045,6 +6045,39 @@  rte_eth_dev_priv_dump(uint16_t port_id, FILE *file)
 	return eth_err(port_id, (*dev->dev_ops->eth_dev_priv_dump)(dev, file));
 }
 
+int
+rte_eth_buffer_split_get_supported_hdr_ptypes(uint16_t port_id, uint32_t *ptypes, int num)
+{
+	int i, j;
+	struct rte_eth_dev *dev;
+	const uint32_t *all_types;
+
+	RTE_ETH_VALID_PORTID_OR_ERR_RET(port_id, -ENODEV);
+	dev = &rte_eth_devices[port_id];
+
+	if (ptypes == NULL && num > 0) {
+		RTE_ETHDEV_LOG(ERR,
+			"Cannot get ethdev port %u supported header protocol types to NULL when array size is non zero\n",
+			port_id);
+		return -EINVAL;
+	}
+
+	if (*dev->dev_ops->buffer_split_supported_hdr_ptypes_get == NULL)
+		return -ENOTSUP;
+	all_types = (*dev->dev_ops->buffer_split_supported_hdr_ptypes_get)(dev);
+
+	if (all_types == NULL)
+		return 0;
+
+	for (i = 0, j = 0; all_types[i] != RTE_PTYPE_UNKNOWN; ++i) {
+		if (j < num)
+			ptypes[j] = all_types[i];
+		j++;
+	}
+
+	return j;
+}
+
 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 a21f58b9cd..c51c1f3fa0 100644
--- a/lib/ethdev/rte_ethdev.h
+++ b/lib/ethdev/rte_ethdev.h
@@ -6025,6 +6025,36 @@  rte_eth_tx_buffer(uint16_t port_id, uint16_t queue_id,
 	return rte_eth_tx_buffer_flush(port_id, queue_id, buffer);
 }
 
+/**
+ * @warning
+ * @b EXPERIMENTAL: this API may change without prior notice
+ *
+ * Get supported header protocols to split on Rx.
+ *
+ * When a packet type is announced to be split, it *must* be supported by
+ * the PMD. For instance, if eth-ipv4, eth-ipv4-udp is announced, the PMD must
+ * return the following packet types for these packets:
+ * - Ether/IPv4             -> RTE_PTYPE_L2_ETHER | RTE_PTYPE_L3_IPV4
+ * - Ether/IPv4/UDP         -> RTE_PTYPE_L2_ETHER | RTE_PTYPE_L3_IPV4 | RTE_PTYPE_L4_UDP
+ *
+ * @param port_id
+ *   The port identifier of the device.
+ * @param[out] ptypes
+ *   An array pointer to store supported protocol headers, allocated by caller.
+ *   These ptypes are composed with RTE_PTYPE_*.
+ * @param num
+ *   Size of the array pointed by param ptypes.
+ * @return
+ *   - (>=0) Number of supported ptypes. If the number of types exceeds num,
+ *           only num entries will be filled into the ptypes array, but the full
+ *           count of supported ptypes will be returned.
+ *   - (-ENOTSUP) if header protocol is not supported by device.
+ *   - (-ENODEV) if *port_id* invalid.
+ *   - (-EINVAL) if bad parameter.
+ */
+__rte_experimental
+int rte_eth_buffer_split_get_supported_hdr_ptypes(uint16_t port_id, uint32_t *ptypes, int num);
+
 #ifdef __cplusplus
 }
 #endif
diff --git a/lib/ethdev/version.map b/lib/ethdev/version.map
index 3def7bfd24..87f06d4ea6 100644
--- a/lib/ethdev/version.map
+++ b/lib/ethdev/version.map
@@ -288,6 +288,7 @@  EXPERIMENTAL {
 
 	# added in 22.11
 	rte_flow_async_action_handle_query;
+	rte_eth_buffer_split_get_supported_hdr_ptypes;
 };
 
 INTERNAL {