ethdev: add simple power management API

Add a simple API to allow getting the monitor conditions for
power-optimized monitoring of the Rx queues from the PMD, as well as
release notes information.

Signed-off-by: Liang Ma <liang.j.ma@intel.com>
Signed-off-by: Anatoly Burakov <anatoly.burakov@intel.com>
Acked-by: Andrew Rybchenko <andrew.rybchenko@oktetlabs.ru>

devtools/libabigail.abignore

@@ -7,3 +7,7 @@
         symbol_version = INTERNAL
 [suppress_variable]
         symbol_version = INTERNAL
+
+; Explicit ignore for driver-only ABI
+[suppress_type]
+        name = eth_dev_ops

doc/guides/rel_notes/release_21_02.rst

@@ -55,6 +55,11 @@ New Features
      Also, make sure to start the actual text at the margin.
      =======================================================
 
+* **Added new ethdev API for PMD power management.**
+
+  Added ``rte_eth_get_monitor_addr()``, to be used in conjunction with
+  ``rte_power_monitor()`` to enable automatic power management for PMDs.
+
 * **Updated Broadcom bnxt driver.**
 
   Updated the Broadcom bnxt driver with fixes and improvements, including:

lib/librte_ethdev/rte_ethdev.c

@@ -5115,6 +5115,34 @@ rte_eth_tx_burst_mode_get(uint16_t port_id, uint16_t queue_id,
 		       dev->dev_ops->tx_burst_mode_get(dev, queue_id, mode));
 }
 
+int
+rte_eth_get_monitor_addr(uint16_t port_id, uint16_t queue_id,
+		struct rte_power_monitor_cond *pmc)
+{
+	struct rte_eth_dev *dev;
+
+	RTE_ETH_VALID_PORTID_OR_ERR_RET(port_id, -ENODEV);
+
+	dev = &rte_eth_devices[port_id];
+
+	RTE_FUNC_PTR_OR_ERR_RET(*dev->dev_ops->get_monitor_addr, -ENOTSUP);
+
+	if (queue_id >= dev->data->nb_rx_queues) {
+		RTE_ETHDEV_LOG(ERR, "Invalid Rx queue_id=%u\n", queue_id);
+		return -EINVAL;
+	}
+
+	if (pmc == NULL) {
+		RTE_ETHDEV_LOG(ERR, "Invalid power monitor condition=%p\n",
+				pmc);
+		return -EINVAL;
+	}
+
+	return eth_err(port_id,
+		dev->dev_ops->get_monitor_addr(dev->data->rx_queues[queue_id],
+			pmc));
+}
+
 int
 rte_eth_dev_set_mc_addr_list(uint16_t port_id,
 			     struct rte_ether_addr *mc_addr_set,

lib/librte_ethdev/rte_ethdev.h

@@ -157,6 +157,7 @@ extern "C" {
 #include <rte_common.h>
 #include <rte_config.h>
 #include <rte_ether.h>
+#include <rte_power_intrinsics.h>
 
 #include "rte_ethdev_trace_fp.h"
 #include "rte_dev_info.h"
@@ -4334,6 +4335,30 @@ __rte_experimental
 int rte_eth_tx_burst_mode_get(uint16_t port_id, uint16_t queue_id,
 	struct rte_eth_burst_mode *mode);
 
+/**
+ * @warning
+ * @b EXPERIMENTAL: this API may change without prior notice.
+ *
+ * Retrieve the monitor condition for a given receive queue.
+ *
+ * @param port_id
+ *   The port identifier of the Ethernet device.
+ * @param queue_id
+ *   The Rx queue on the Ethernet device for which information
+ *   will be retrieved.
+ * @param pmc
+ *   The pointer to power-optimized monitoring condition structure.
+ *
+ * @return
+ *   - 0: Success.
+ *   -ENOTSUP: Operation not supported.
+ *   -EINVAL: Invalid parameters.
+ *   -ENODEV: Invalid port ID.
+ */
+__rte_experimental
+int rte_eth_get_monitor_addr(uint16_t port_id, uint16_t queue_id,
+		struct rte_power_monitor_cond *pmc);
+
 /**
  * Retrieve device registers and register attributes (number of registers and
  * register size)

lib/librte_ethdev/rte_ethdev_driver.h

@@ -763,6 +763,26 @@ typedef int (*eth_hairpin_queue_peer_unbind_t)
 	(struct rte_eth_dev *dev, uint16_t cur_queue, uint32_t direction);
 /**< @internal Unbind peer queue from the current queue. */
 
+/**
+ * @internal
+ * Get address of memory location whose contents will change whenever there is
+ * new data to be received on an Rx queue.
+ *
+ * @param rxq
+ *   Ethdev queue pointer.
+ * @param pmc
+ *   The pointer to power-optimized monitoring condition structure.
+ * @return
+ *   Negative errno value on error, 0 on success.
+ *
+ * @retval 0
+ *   Success
+ * @retval -EINVAL
+ *   Invalid parameters
+ */
+typedef int (*eth_get_monitor_addr_t)(void *rxq,
+		struct rte_power_monitor_cond *pmc);
+
 /**
  * @internal A structure containing the functions exported by an Ethernet driver.
  */
@@ -917,6 +937,9 @@ struct eth_dev_ops {
 	/**< Set up the connection between the pair of hairpin queues. */
 	eth_hairpin_queue_peer_unbind_t hairpin_queue_peer_unbind;
 	/**< Disconnect the hairpin queues of a pair from each other. */
+
+	eth_get_monitor_addr_t get_monitor_addr;
+	/**< Get power monitoring condition for Rx queue. */
 };
 
 /**

lib/librte_ethdev/version.map

@@ -240,6 +240,9 @@ EXPERIMENTAL {
 	rte_flow_get_restore_info;
 	rte_flow_tunnel_action_decap_release;
 	rte_flow_tunnel_item_release;
+
+	# added in 21.02
+	rte_eth_get_monitor_addr;
 };
 
 INTERNAL {