target/linux/layerscape/patches-5.4/701-net-0071-sdk_dpaa-ceetm-drain-the-ceetm-CQs-on-destroy.patch

   1 From fe7ed61721646077de5eb06a105e60634374a00c Mon Sep 17 00:00:00 2001
   2 From: Camelia Groza <camelia.groza@nxp.com>
   3 Date: Thu, 31 May 2018 10:45:50 +0300
   4 Subject: [PATCH] sdk_dpaa: ceetm: drain the ceetm CQs on destroy
   5
   6 The CEETM CQs must be empty when configured. To guarantee this, stop all
   7 transmissions and wait for them to drain before releasing them. On the
   8 next configuration, we are certain they will be empty.
   9
  10 Signed-off-by: Camelia Groza <camelia.groza@nxp.com>
  11 ---
  12  .../ethernet/freescale/sdk_dpaa/dpaa_eth_ceetm.c   | 62 ++++++++++++++++++++++
  13  1 file changed, 62 insertions(+)
  14
  15 --- a/drivers/net/ethernet/freescale/sdk_dpaa/dpaa_eth_ceetm.c
  16 +++ b/drivers/net/ethernet/freescale/sdk_dpaa/dpaa_eth_ceetm.c
  17 @@ -90,6 +90,51 @@ static void dpaa_drain_fqs(struct net_de
  18         }
  19  }
  20
  21 +/* Wait for the DPAA CEETM TX CQs to empty */
  22 +static void ceetm_drain_class(struct ceetm_class *cl)
  23 +{
  24 +       struct qm_mcr_ceetm_cq_query cq_query;
  25 +       struct qm_ceetm_cq *cq;
  26 +       unsigned int idx;
  27 +       int ret;
  28 +
  29 +       if (!cl)
  30 +               return;
  31 +
  32 +       switch (cl->type) {
  33 +       case CEETM_ROOT:
  34 +               /* The ROOT classes aren't directly linked to CEETM CQs */
  35 +               return;
  36 +       case CEETM_PRIO:
  37 +               cq = (struct qm_ceetm_cq*)cl->prio.cq;
  38 +               break;
  39 +       case CEETM_WBFS:
  40 +               cq = (struct qm_ceetm_cq*)cl->wbfs.cq;
  41 +               break;
  42 +       }
  43 +
  44 +       if (!cq || !cl->ch)
  45 +               return;
  46 +
  47 +       /* Build the query CQID by merging the channel and the CQ IDs */
  48 +       idx = (cq->parent->idx << 4) | cq->idx;
  49 +
  50 +       while (true) {
  51 +               ret = qman_ceetm_query_cq(idx,
  52 +                                         cl->ch->dcp_idx,
  53 +                                         &cq_query);
  54 +               if (unlikely(ret)) {
  55 +                       pr_err(KBUILD_BASENAME
  56 +                              " : %s : unable to query CQ %x: %d\n",
  57 +                              __func__, idx, ret);
  58 +                       break;
  59 +               }
  60 +
  61 +               if (cq_query.frm_cnt == 0)
  62 +                       break;
  63 +       }
  64 +}
  65 +
  66  /* Enqueue Rejection Notification callback */
  67  static void ceetm_ern(struct qman_portal *portal, struct qman_fq *fq,
  68                       const struct qm_mr_entry *msg)
  69 @@ -376,6 +421,8 @@ static void ceetm_link_class(struct Qdis
  70  /* Destroy a ceetm class */
  71  static void ceetm_cls_destroy(struct Qdisc *sch, struct ceetm_class *cl)
  72  {
  73 +       struct net_device *dev = qdisc_dev(sch);
  74 +
  75         if (!cl)
  76                 return;
  77
  78 @@ -402,6 +449,12 @@ static void ceetm_cls_destroy(struct Qdi
  79                         cl->prio.child = NULL;
  80                 }
  81
  82 +               /* We must make sure the CQ is empty before releasing it.
  83 +                * Pause all transmissions while we wait for it to drain.
  84 +                */
  85 +               netif_tx_stop_all_queues(dev);
  86 +               ceetm_drain_class(cl);
  87 +
  88                 if (cl->prio.lfq && qman_ceetm_lfq_release(cl->prio.lfq))
  89                         pr_err(KBUILD_BASENAME
  90                                " : %s : error releasing the LFQ %d\n",
  91 @@ -422,9 +475,16 @@ static void ceetm_cls_destroy(struct Qdi
  92                 if (cl->prio.cstats)
  93                         free_percpu(cl->prio.cstats);
  94
  95 +               netif_tx_wake_all_queues(dev);
  96                 break;
  97
  98         case CEETM_WBFS:
  99 +               /* We must make sure the CQ is empty before releasing it.
 100 +                * Pause all transmissions while we wait for it to drain.
 101 +                */
 102 +               netif_tx_stop_all_queues(dev);
 103 +               ceetm_drain_class(cl);
 104 +
 105                 if (cl->wbfs.lfq && qman_ceetm_lfq_release(cl->wbfs.lfq))
 106                         pr_err(KBUILD_BASENAME
 107                                " : %s : error releasing the LFQ %d\n",
 108 @@ -444,6 +504,8 @@ static void ceetm_cls_destroy(struct Qdi
 109
 110                 if (cl->wbfs.cstats)
 111                         free_percpu(cl->wbfs.cstats);
 112 +
 113 +               netif_tx_wake_all_queues(dev);
 114         }
 115
 116         tcf_block_put(cl->block);