Merge remote-tracking branch 'torvalds/master' into perf/core

[linux-2.6-microblaze.git] / drivers / net / ethernet / xilinx / ll_temac_main.c

diff --git a/drivers/net/ethernet/xilinx/ll_temac_main.c b/drivers/net/ethernet/xilinx/ll_temac_main.c
index a1f5f07..9a13953 100644 (file)
--- a/drivers/net/ethernet/xilinx/ll_temac_main.c
+++ b/drivers/net/ethernet/xilinx/ll_temac_main.c
@@ -774,12 +774,15 @@ 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;
@@ -788,6 +791,12 @@ 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 >= lp->tx_bd_num)
                        lp->tx_bd_ci = 0;
@@ -814,6 +823,9 @@ 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 >= lp->tx_bd_num)
                        tail = 0;
@@ -849,7 +861,7 @@ temac_start_xmit(struct sk_buff *skb, struct net_device *ndev)
                smp_mb();
 
                /* Space might have just been freed - check again */
-               if (temac_check_tx_bd_space(lp, num_frag))
+               if (temac_check_tx_bd_space(lp, num_frag + 1))
                        return NETDEV_TX_BUSY;
 
                netif_wake_queue(ndev);
@@ -876,7 +888,6 @@ temac_start_xmit(struct sk_buff *skb, struct net_device *ndev)
                return NETDEV_TX_OK;
        }
        cur_p->phys = cpu_to_be32(skb_dma_addr);
-       ptr_to_txbd((void *)skb, cur_p);
 
        for (ii = 0; ii < num_frag; ii++) {
                if (++lp->tx_bd_tail >= lp->tx_bd_num)
@@ -915,6 +926,11 @@ temac_start_xmit(struct sk_buff *skb, struct net_device *ndev)
        }
        cur_p->app0 |= cpu_to_be32(STS_CTRL_APP0_EOP);
 
+       /* Mark last fragment with skb address, so it can be consumed
+        * in temac_start_xmit_done()
+        */
+       ptr_to_txbd((void *)skb, cur_p);
+
        tail_p = lp->tx_bd_p + sizeof(*lp->tx_bd_v) * lp->tx_bd_tail;
        lp->tx_bd_tail++;
        if (lp->tx_bd_tail >= lp->tx_bd_num)
@@ -926,6 +942,11 @@ temac_start_xmit(struct sk_buff *skb, struct net_device *ndev)
        wmb();
        lp->dma_out(lp, TX_TAILDESC_PTR, tail_p); /* DMA start */
 
+       if (temac_check_tx_bd_space(lp, MAX_SKB_FRAGS + 1)) {
+               netdev_info(ndev, "%s -> netif_stop_queue\n", __func__);
+               netif_stop_queue(ndev);
+       }
+
        return NETDEV_TX_OK;
 }