[v3] net/bnxt: fix Rx descriptor status

  From: Lance Richardson <lance.richardson@broadcom.com>

Fix a number of issues in the bnxt receive descriptor status
function, including:
   - Provide status of receive descriptor instead of completion
     descriptor.
   - Remove invalid comparison of raw ring index with masked ring
     index.
   - Correct misinterpretation of offset parameter as ring index.
   - Correct misuse of completion ring index for mbuf ring (the
     two rings have different sizes).

Fixes: 0fe613bb87b2 ("net/bnxt: support Rx descriptor status")
Cc: stable@dpdk.org

Signed-off-by: Lance Richardson <lance.richardson@broadcom.com>
Reviewed-by: Andy Gospodarek <gospo@broadcom.com>
Reviewed-by: Ajit Khaparde <ajit.khaparde@broadcom.com>
---
v1->v2: rebase against latest tree.
v2->v3: fix compilation on PPC. Compile tested only.
---
 drivers/net/bnxt/bnxt_ethdev.c | 110 ++++++++++++++++++++++++++-------
 1 file changed, 88 insertions(+), 22 deletions(-)
  

On Thu, Mar 11, 2021 at 12:05 PM Ajit Khaparde
<ajit.khaparde@broadcom.com> wrote:
>
> From: Lance Richardson <lance.richardson@broadcom.com>
>
> Fix a number of issues in the bnxt receive descriptor status
> function, including:
>    - Provide status of receive descriptor instead of completion
>      descriptor.
>    - Remove invalid comparison of raw ring index with masked ring
>      index.
>    - Correct misinterpretation of offset parameter as ring index.
>    - Correct misuse of completion ring index for mbuf ring (the
>      two rings have different sizes).
>
> Fixes: 0fe613bb87b2 ("net/bnxt: support Rx descriptor status")
> Cc: stable@dpdk.org
>
> Signed-off-by: Lance Richardson <lance.richardson@broadcom.com>
> Reviewed-by: Andy Gospodarek <gospo@broadcom.com>
> Reviewed-by: Ajit Khaparde <ajit.khaparde@broadcom.com>
> ---
> v1->v2: rebase against latest tree.
> v2->v3: fix compilation on PPC. Compile tested only.

Patch applied to dpdk-next-net-brcm. Thanks

> ---
>  drivers/net/bnxt/bnxt_ethdev.c | 110 ++++++++++++++++++++++++++-------
>  1 file changed, 88 insertions(+), 22 deletions(-)
>
> diff --git a/drivers/net/bnxt/bnxt_ethdev.c b/drivers/net/bnxt/bnxt_ethdev.c
> index c55a2d8197..cefd6915d7 100644
> --- a/drivers/net/bnxt/bnxt_ethdev.c
> +++ b/drivers/net/bnxt/bnxt_ethdev.c
> @@ -3076,42 +3076,108 @@ bnxt_rx_queue_count_op(struct rte_eth_dev *dev, uint16_t rx_queue_id)
>  static int
>  bnxt_rx_descriptor_status_op(void *rx_queue, uint16_t offset)
>  {
> -       struct bnxt_rx_queue *rxq = (struct bnxt_rx_queue *)rx_queue;
> -       struct bnxt_rx_ring_info *rxr;
> +       struct bnxt_rx_queue *rxq = rx_queue;
>         struct bnxt_cp_ring_info *cpr;
> -       struct rte_mbuf *rx_buf;
> +       struct bnxt_rx_ring_info *rxr;
> +       uint32_t desc, cons, raw_cons;
> +       struct bnxt *bp = rxq->bp;
>         struct rx_pkt_cmpl *rxcmp;
> -       uint32_t cons, cp_cons;
>         int rc;
>
> -       if (!rxq)
> -               return -EINVAL;
> -
> -       rc = is_bnxt_in_error(rxq->bp);
> +       rc = is_bnxt_in_error(bp);
>         if (rc)
>                 return rc;
>
> -       cpr = rxq->cp_ring;
> -       rxr = rxq->rx_ring;
> -
>         if (offset >= rxq->nb_rx_desc)
>                 return -EINVAL;
>
> -       cons = RING_CMP(cpr->cp_ring_struct, offset);
> -       cp_cons = cpr->cp_raw_cons;
> -       rxcmp = (struct rx_pkt_cmpl *)&cpr->cp_desc_ring[cons];
> +       rxr = rxq->rx_ring;
> +       cpr = rxq->cp_ring;
>
> -       if (cons > cp_cons) {
> -               if (CMPL_VALID(rxcmp, cpr->valid))
> -                       return RTE_ETH_RX_DESC_DONE;
> -       } else {
> -               if (CMPL_VALID(rxcmp, !cpr->valid))
> +       /*
> +        * For the vector receive case, the completion at the requested
> +        * offset can be indexed directly.
> +        */
> +#if defined(RTE_ARCH_X86) || defined(RTE_ARCH_ARM64)
> +       if (bp->flags & BNXT_FLAG_RX_VECTOR_PKT_MODE) {
> +               struct rx_pkt_cmpl *rxcmp;
> +
> +               /* Check status of completion descriptor. */
> +               raw_cons = cpr->cp_raw_cons +
> +                          offset * CMP_LEN(CMPL_BASE_TYPE_RX_L2);
> +               cons = RING_CMP(cpr->cp_ring_struct, raw_cons);
> +               rxcmp = (struct rx_pkt_cmpl *)&cpr->cp_desc_ring[cons];
> +
> +               if (CMP_VALID(rxcmp, raw_cons, cpr->cp_ring_struct))
>                         return RTE_ETH_RX_DESC_DONE;
> +
> +               /* Check whether rx desc has an mbuf attached. */
> +               cons = RING_CMP(rxr->rx_ring_struct, raw_cons / 2);
> +               if (cons >= rxq->rxrearm_start &&
> +                   cons < rxq->rxrearm_start + rxq->rxrearm_nb) {
> +                       return RTE_ETH_RX_DESC_UNAVAIL;
> +               }
> +
> +               return RTE_ETH_RX_DESC_AVAIL;
>         }
> -       rx_buf = rxr->rx_buf_ring[cons];
> -       if (rx_buf == NULL || rx_buf == &rxq->fake_mbuf)
> -               return RTE_ETH_RX_DESC_UNAVAIL;
> +#endif
> +
> +       /*
> +        * For the non-vector receive case, scan the completion ring to
> +        * locate the completion descriptor for the requested offset.
> +        */
> +       raw_cons = cpr->cp_raw_cons;
> +       desc = 0;
> +       while (1) {
> +               uint32_t agg_cnt, cons, cmpl_type;
> +
> +               cons = RING_CMP(cpr->cp_ring_struct, raw_cons);
> +               rxcmp = (struct rx_pkt_cmpl *)&cpr->cp_desc_ring[cons];
>
> +               if (!CMP_VALID(rxcmp, raw_cons, cpr->cp_ring_struct))
> +                       break;
> +
> +               cmpl_type = CMP_TYPE(rxcmp);
> +
> +               switch (cmpl_type) {
> +               case CMPL_BASE_TYPE_RX_L2:
> +               case CMPL_BASE_TYPE_RX_L2_V2:
> +                       if (desc == offset) {
> +                               cons = rxcmp->opaque;
> +                               if (rxr->rx_buf_ring[cons])
> +                                       return RTE_ETH_RX_DESC_DONE;
> +                               else
> +                                       return RTE_ETH_RX_DESC_UNAVAIL;
> +                       }
> +                       agg_cnt = BNXT_RX_L2_AGG_BUFS(rxcmp);
> +                       raw_cons = raw_cons + CMP_LEN(cmpl_type) + agg_cnt;
> +                       desc++;
> +                       break;
> +
> +               case CMPL_BASE_TYPE_RX_TPA_END:
> +                       if (desc == offset)
> +                               return RTE_ETH_RX_DESC_DONE;
> +
> +                       if (BNXT_CHIP_P5(rxq->bp)) {
> +                               struct rx_tpa_v2_end_cmpl_hi *p5_tpa_end;
> +
> +                               p5_tpa_end = (void *)rxcmp;
> +                               agg_cnt = BNXT_TPA_END_AGG_BUFS_TH(p5_tpa_end);
> +                       } else {
> +                               struct rx_tpa_end_cmpl *tpa_end;
> +
> +                               tpa_end = (void *)rxcmp;
> +                               agg_cnt = BNXT_TPA_END_AGG_BUFS(tpa_end);
> +                       }
> +
> +                       raw_cons = raw_cons + CMP_LEN(cmpl_type) + agg_cnt;
> +                       desc++;
> +                       break;
> +
> +               default:
> +                       raw_cons += CMP_LEN(cmpl_type);
> +               }
> +       }
>
>         return RTE_ETH_RX_DESC_AVAIL;
>  }
> --
> 2.21.1 (Apple Git-122.3)
>