net/sfc: support Rx descriptor status API

[dpdk.git] / drivers / net / sfc / sfc_rx.c

diff --git a/drivers/net/sfc/sfc_rx.c b/drivers/net/sfc/sfc_rx.c
index 364f718..3b17b9a 100644 (file)
--- a/drivers/net/sfc/sfc_rx.c
+++ b/drivers/net/sfc/sfc_rx.c
@@ -349,6 +349,43 @@ sfc_efx_rx_qdesc_npending(struct sfc_dp_rxq *dp_rxq)
        return rxq->pending - rxq->completed;
 }
 
+static sfc_dp_rx_qdesc_status_t sfc_efx_rx_qdesc_status;
+static int
+sfc_efx_rx_qdesc_status(struct sfc_dp_rxq *dp_rxq, uint16_t offset)
+{
+       struct sfc_efx_rxq *rxq = sfc_efx_rxq_by_dp_rxq(dp_rxq);
+
+       if (unlikely(offset > rxq->ptr_mask))
+               return -EINVAL;
+
+       /*
+        * Poll EvQ to derive up-to-date 'rxq->pending' figure;
+        * it is required for the queue to be running, but the
+        * check is omitted because API design assumes that it
+        * is the duty of the caller to satisfy all conditions
+        */
+       SFC_ASSERT((rxq->flags & SFC_EFX_RXQ_FLAG_RUNNING) ==
+                  SFC_EFX_RXQ_FLAG_RUNNING);
+       sfc_ev_qpoll(rxq->evq);
+
+       /*
+        * There is a handful of reserved entries in the ring,
+        * but an explicit check whether the offset points to
+        * a reserved entry is neglected since the two checks
+        * below rely on the figures which take the HW limits
+        * into account and thus if an entry is reserved, the
+        * checks will fail and UNAVAIL code will be returned
+        */
+
+       if (offset < (rxq->pending - rxq->completed))
+               return RTE_ETH_RX_DESC_DONE;
+
+       if (offset < (rxq->added - rxq->completed))
+               return RTE_ETH_RX_DESC_AVAIL;
+
+       return RTE_ETH_RX_DESC_UNAVAIL;
+}
+
 struct sfc_rxq *
 sfc_rxq_by_dp_rxq(const struct sfc_dp_rxq *dp_rxq)
 {
@@ -498,6 +535,7 @@ struct sfc_dp_rx sfc_efx_rx = {
        .qpurge                 = sfc_efx_rx_qpurge,
        .supported_ptypes_get   = sfc_efx_supported_ptypes_get,
        .qdesc_npending         = sfc_efx_rx_qdesc_npending,
+       .qdesc_status           = sfc_efx_rx_qdesc_status,
        .pkt_burst              = sfc_efx_recv_pkts,
 };