[PATCH net-next V3 13/16] net: fec: detect tx int lost

[Troy Kisky]

If a tx int is lost, no need to reset
the fec. Just mark the event and call napi_schedule.

Signed-off-by: Troy Kisky <troy.ki...@boundarydevices.com>

---
v3: no change
---
 drivers/net/ethernet/freescale/fec_main.c | 38 ++++++++++++++++++++++++++++++-
 1 file changed, 37 insertions(+), 1 deletion(-)

diff --git a/drivers/net/ethernet/freescale/fec_main.c 
b/drivers/net/ethernet/freescale/fec_main.c
index be875fd..445443d 100644
--- a/drivers/net/ethernet/freescale/fec_main.c
+++ b/drivers/net/ethernet/freescale/fec_main.c
@@ -1094,14 +1094,50 @@ fec_stop(struct net_device *ndev)
        }
 }
 
+static const uint txint_flags[] = {
+       FEC_ENET_TXF_0, FEC_ENET_TXF_1, FEC_ENET_TXF_2
+};
 
 static void
 fec_timeout(struct net_device *ndev)
 {
        struct fec_enet_private *fep = netdev_priv(ndev);
+       struct bufdesc *bdp;
+       unsigned short status;
+       int i;
+       uint events = 0;
 
-       fec_dump(ndev);
+       for (i = 0; i < fep->num_tx_queues; i++) {
+               struct fec_enet_priv_tx_q *txq = fep->tx_queue[i];
+               int index;
+               struct sk_buff *skb = NULL;
 
+               bdp = txq->dirty_tx;
+               while (1) {
+                       bdp = fec_enet_get_nextdesc(bdp, &txq->bd);
+                       if (bdp == txq->bd.cur)
+                               break;
+                       index = fec_enet_get_bd_index(bdp, &txq->bd);
+                       skb = txq->tx_skbuff[index];
+                       if (skb) {
+                               status = fec16_to_cpu(bdp->cbd_sc);
+                               if ((status & BD_ENET_TX_READY) == 0)
+                                       events |= txint_flags[i];
+                               break;
+                       }
+               }
+       }
+       if (events) {
+               fep->events |= events;
+               /* Disable the RX/TX interrupt */
+               writel(FEC_NAPI_IMASK, fep->hwp + FEC_IMASK);
+               napi_schedule(&fep->napi);
+               netif_wake_queue(fep->netdev);
+               pr_err("%s: tx int lost\n", __func__);
+               return;
+       }
+
+       fec_dump(ndev);
        ndev->stats.tx_errors++;
 
        schedule_work(&fep->tx_timeout_work);
-- 
2.5.0