[PATCH] common/cnxk: add workaround for vWQE flush

[Jerin Jacob]

On Tue, Dec 14, 2021 at 2:24 AM <pbhagavatula at marvell.com> wrote:
>
> From: Pavan Nikhilesh <pbhagavatula at marvell.com>
>
> Due to an errata writing to vWQE flush register might hang NIX.
> Add workaround for vWQE flush hang by waiting for the max
> coalescing timeout to flush out any pending vWQEs.


    Fixes: ee48f711f3b0 ("common/cnxk: support NIX inline inbound and
outbound setup")
    Cc: stable at dpdk.org

>
> Signed-off-by: Pavan Nikhilesh <pbhagavatula at marvell.com>

Acked-by: Jerin Jacob <jerinj at marvell.com>
Applied to dpdk-next-net-eventdev/for-main. Thanks

> ---
>  drivers/common/cnxk/roc_nix_inl.c      |  3 +--
>  drivers/common/cnxk/roc_nix_inl_dev.c  | 12 ++++++++++++
>  drivers/common/cnxk/roc_nix_inl_priv.h |  1 +
>  drivers/common/cnxk/roc_nix_priv.h     |  1 +
>  drivers/common/cnxk/roc_nix_queue.c    | 19 +++++++++++++++++--
>  5 files changed, 32 insertions(+), 4 deletions(-)
>
> diff --git a/drivers/common/cnxk/roc_nix_inl.c b/drivers/common/cnxk/roc_nix_inl.c
> index f0fc690417..e8981c4aa4 100644
> --- a/drivers/common/cnxk/roc_nix_inl.c
> +++ b/drivers/common/cnxk/roc_nix_inl.c
> @@ -595,8 +595,7 @@ roc_nix_inl_dev_rq_put(struct roc_nix_rq *rq)
>                 plt_err("Failed to disable inline device rq, rc=%d", rc);
>
>         /* Flush NIX LF for CN10K */
> -       if (roc_model_is_cn10k())
> -               plt_write64(0, inl_dev->nix_base + NIX_LF_OP_VWQE_FLUSH);
> +       nix_rq_vwqe_flush(rq, inl_dev->vwqe_interval);
>
>         return rc;
>  }
> diff --git a/drivers/common/cnxk/roc_nix_inl_dev.c b/drivers/common/cnxk/roc_nix_inl_dev.c
> index a0fe6ecd82..10912a6c93 100644
> --- a/drivers/common/cnxk/roc_nix_inl_dev.c
> +++ b/drivers/common/cnxk/roc_nix_inl_dev.c
> @@ -346,6 +346,7 @@ nix_inl_nix_setup(struct nix_inl_dev *inl_dev)
>         struct mbox *mbox = dev->mbox;
>         struct nix_lf_alloc_rsp *rsp;
>         struct nix_lf_alloc_req *req;
> +       struct nix_hw_info *hw_info;
>         size_t inb_sa_sz;
>         int i, rc = -ENOSPC;
>         void *sa;
> @@ -382,6 +383,17 @@ nix_inl_nix_setup(struct nix_inl_dev *inl_dev)
>         inl_dev->qints = rsp->qints;
>         inl_dev->cints = rsp->cints;
>
> +       /* Get VWQE info if supported */
> +       if (roc_model_is_cn10k()) {
> +               mbox_alloc_msg_nix_get_hw_info(mbox);
> +               rc = mbox_process_msg(mbox, (void *)&hw_info);
> +               if (rc) {
> +                       plt_err("Failed to get HW info, rc=%d", rc);
> +                       goto lf_free;
> +               }
> +               inl_dev->vwqe_interval = hw_info->vwqe_delay;
> +       }
> +
>         /* Register nix interrupts */
>         rc = nix_inl_nix_register_irqs(inl_dev);
>         if (rc) {
> diff --git a/drivers/common/cnxk/roc_nix_inl_priv.h b/drivers/common/cnxk/roc_nix_inl_priv.h
> index 3dc526f929..be53a3fa81 100644
> --- a/drivers/common/cnxk/roc_nix_inl_priv.h
> +++ b/drivers/common/cnxk/roc_nix_inl_priv.h
> @@ -35,6 +35,7 @@ struct nix_inl_dev {
>         /* NIX data */
>         uint8_t lf_tx_stats;
>         uint8_t lf_rx_stats;
> +       uint16_t vwqe_interval;
>         uint16_t cints;
>         uint16_t qints;
>         struct roc_nix_rq rq;
> diff --git a/drivers/common/cnxk/roc_nix_priv.h b/drivers/common/cnxk/roc_nix_priv.h
> index 04575af295..deb2a6ba11 100644
> --- a/drivers/common/cnxk/roc_nix_priv.h
> +++ b/drivers/common/cnxk/roc_nix_priv.h
> @@ -377,6 +377,7 @@ int nix_rq_cfg(struct dev *dev, struct roc_nix_rq *rq, uint16_t qints, bool cfg,
>  int nix_rq_ena_dis(struct dev *dev, struct roc_nix_rq *rq, bool enable);
>  int nix_tm_bp_config_get(struct roc_nix *roc_nix, bool *is_enabled);
>  int nix_tm_bp_config_set(struct roc_nix *roc_nix, bool enable);
> +void nix_rq_vwqe_flush(struct roc_nix_rq *rq, uint16_t vwqe_interval);
>
>  /*
>   * TM priv utils.
> diff --git a/drivers/common/cnxk/roc_nix_queue.c b/drivers/common/cnxk/roc_nix_queue.c
> index c8c8401d81..d5f6813e69 100644
> --- a/drivers/common/cnxk/roc_nix_queue.c
> +++ b/drivers/common/cnxk/roc_nix_queue.c
> @@ -28,6 +28,22 @@ nix_qsize_clampup(uint32_t val)
>         return i;
>  }
>
> +void
> +nix_rq_vwqe_flush(struct roc_nix_rq *rq, uint16_t vwqe_interval)
> +{
> +       uint64_t wait_ns;
> +
> +       if (!roc_model_is_cn10k())
> +               return;
> +       /* Due to HW errata writes to VWQE_FLUSH might hang, so instead
> +        * wait for max vwqe timeout interval.
> +        */
> +       if (rq->vwqe_ena) {
> +               wait_ns = rq->vwqe_wait_tmo * (vwqe_interval + 1) * 100;
> +               plt_delay_us((wait_ns / 1E3) + 1);
> +       }
> +}
> +
>  int
>  nix_rq_ena_dis(struct dev *dev, struct roc_nix_rq *rq, bool enable)
>  {
> @@ -66,9 +82,8 @@ roc_nix_rq_ena_dis(struct roc_nix_rq *rq, bool enable)
>         int rc;
>
>         rc = nix_rq_ena_dis(&nix->dev, rq, enable);
> +       nix_rq_vwqe_flush(rq, nix->vwqe_interval);
>
> -       if (roc_model_is_cn10k())
> -               plt_write64(rq->qid, nix->base + NIX_LF_OP_VWQE_FLUSH);
>         return rc;
>  }
>
> --
> 2.17.1
>