diff --git a/drivers/net/ethernet/xilinx/ll_temac_main.c b/drivers/net/ethernet/xilinx/ll_temac_main.c index 9b55fbdc3a7c..d3d9f7046913 100644 --- a/drivers/net/ethernet/xilinx/ll_temac_main.c +++ b/drivers/net/ethernet/xilinx/ll_temac_main.c @@ -770,12 +770,15 @@ static void temac_start_xmit_done(struct net_device *ndev) stat = be32_to_cpu(cur_p->app0); while (stat & STS_CTRL_APP0_CMPLT) { + /* Make sure that the other fields are read after bd is + * released by dma + */ + rmb(); dma_unmap_single(ndev->dev.parent, be32_to_cpu(cur_p->phys), be32_to_cpu(cur_p->len), DMA_TO_DEVICE); skb = (struct sk_buff *)ptr_from_txbd(cur_p); if (skb) dev_consume_skb_irq(skb); - cur_p->app0 = 0; cur_p->app1 = 0; cur_p->app2 = 0; cur_p->app3 = 0; @@ -784,6 +787,12 @@ static void temac_start_xmit_done(struct net_device *ndev) ndev->stats.tx_packets++; ndev->stats.tx_bytes += be32_to_cpu(cur_p->len); + /* app0 must be visible last, as it is used to flag + * availability of the bd + */ + smp_mb(); + cur_p->app0 = 0; + lp->tx_bd_ci++; if (lp->tx_bd_ci >= TX_BD_NUM) lp->tx_bd_ci = 0; @@ -810,6 +819,9 @@ static inline int temac_check_tx_bd_space(struct temac_local *lp, int num_frag) if (cur_p->app0) return NETDEV_TX_BUSY; + /* Make sure to read next bd app0 after this one */ + rmb(); + tail++; if (tail >= TX_BD_NUM) tail = 0;