net/sfc: support ops to check ready descriptors in ESSB Rx

Implement EF10 ESSB Rx datapath callback to get number of pending
descriptors.

Signed-off-by: Andrew Rybchenko <arybchenko@solarflare.com>
Reviewed-by: Ivan Malov <ivan.malov@oktetlabs.ru>

diff --git a/drivers/net/sfc/sfc_ef10_essb_rx.c b/drivers/net/sfc/sfc_ef10_essb_rx.c
index 000de2e..8428a31 100644 (file)
--- a/drivers/net/sfc/sfc_ef10_essb_rx.c
+++ b/drivers/net/sfc/sfc_ef10_essb_rx.c
@@ -411,13 +411,28 @@ sfc_ef10_essb_recv_pkts(void *rx_queue, struct rte_mbuf **rx_pkts,
 
 static sfc_dp_rx_qdesc_npending_t sfc_ef10_essb_rx_qdesc_npending;
 static unsigned int
-sfc_ef10_essb_rx_qdesc_npending(__rte_unused struct sfc_dp_rxq *dp_rxq)
+sfc_ef10_essb_rx_qdesc_npending(struct sfc_dp_rxq *dp_rxq)
 {
-       /*
-        * Correct implementation requires EvQ polling and events
-        * processing.
-        */
-       return -ENOTSUP;
+       struct sfc_ef10_essb_rxq *rxq = sfc_ef10_essb_rxq_by_dp_rxq(dp_rxq);
+       const unsigned int evq_old_read_ptr = rxq->evq_read_ptr;
+       efx_qword_t rx_ev;
+
+       if (unlikely(rxq->flags & (SFC_EF10_ESSB_RXQ_NOT_RUNNING |
+                                  SFC_EF10_ESSB_RXQ_EXCEPTION)))
+               return rxq->bufs_pending;
+
+       while (sfc_ef10_essb_rx_event_get(rxq, &rx_ev)) {
+               /*
+                * DROP_EVENT is an internal to the NIC, software should
+                * never see it and, therefore, may ignore it.
+                */
+               sfc_ef10_essb_rx_process_ev(rxq, rx_ev);
+       }
+
+       sfc_ef10_ev_qclear(rxq->evq_hw_ring, rxq->evq_ptr_mask,
+                          evq_old_read_ptr, rxq->evq_read_ptr);
+
+       return rxq->bufs_pending;
 }
 
 static sfc_dp_rx_qdesc_status_t sfc_ef10_essb_rx_qdesc_status;