[ramips] hopefully fixes dma issues seen on ethernet driver when under high load

git-svn-id: svn://svn.openwrt.org/openwrt/trunk@18203 3c298f89-4303-0410-b956-a3cf2f4a3e73

diff --git a/target/linux/ramips/files/drivers/net/ramips.c b/target/linux/ramips/files/drivers/net/ramips.c
index 7168f18..b1cc550 100644 (file)
--- a/target/linux/ramips/files/drivers/net/ramips.c
+++ b/target/linux/ramips/files/drivers/net/ramips.c
@@ -147,6 +147,8 @@ ramips_eth_hard_start_xmit(struct sk_buff* skb, struct net_device *dev)
        unsigned long tx;
        unsigned int tx_next;
        unsigned int mapped_addr;
+
+
        if(priv->plat->min_pkt_len)
        {
                if(skb->len < priv->plat->min_pkt_len)
@@ -169,9 +171,9 @@ ramips_eth_hard_start_xmit(struct sk_buff* skb, struct net_device *dev)
                tx_next = 0;
        else
                tx_next = tx + 1;
-       if((priv->tx_skb[tx]== 0) && (priv->tx_skb[tx_next] == 0))
+       if((priv->tx_skb[tx] == 0) && (priv->tx_skb[tx_next] == 0))
        {
-               if(!(priv->tx[tx].txd2 & TX_DMA_DONE))
+               if(!(priv->tx[tx].txd2 & TX_DMA_DONE) || !(priv->tx[tx_next].txd2 & TX_DMA_DONE))
                {
                        kfree_skb(skb);
                        dev->stats.tx_dropped++;
@@ -181,10 +183,12 @@ ramips_eth_hard_start_xmit(struct sk_buff* skb, struct net_device *dev)
                priv->tx[tx].txd1 = virt_to_phys(skb->data);
                priv->tx[tx].txd2 &= ~(TX_DMA_PLEN0_MASK | TX_DMA_DONE);
                priv->tx[tx].txd2 |= TX_DMA_PLEN0(skb->len);
+               wmb();
                ramips_fe_wr((tx + 1) % NUM_TX_DESC, RAMIPS_TX_CTX_IDX0);
                dev->stats.tx_packets++;
                dev->stats.tx_bytes += skb->len;
                priv->tx_skb[tx] = skb;
+               wmb();
                ramips_fe_wr((tx + 1) % NUM_TX_DESC, RAMIPS_TX_CTX_IDX0);
        } else {
                dev->stats.tx_dropped++;
@@ -228,6 +232,7 @@ ramips_eth_rx_hw(unsigned long ptr)
                        dma_map_single(NULL, new_skb->data, MAX_RX_LENGTH + 2,
                        DMA_FROM_DEVICE);
                priv->rx[rx].rxd2 &= ~RX_DMA_DONE;
+               wmb();
                ramips_fe_wr(rx, RAMIPS_RX_CALC_IDX0);
        }
        if(max_rx == 0)