tg3: Add memory barriers to sync BD data

for weak memory model architectures to ensure that the chip will DMA
valid BD data.

Signed-off-by: Michael Chan <mchan@broadcom.com>
Reviewed-by: Benjamin Li <benli@broadcom.com>
Reviewed-by: Matt Carlson <mcarlson@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/drivers/net/ethernet/broadcom/tg3.c b/drivers/net/ethernet/broadcom/tg3.c
index 4b3243b2bdf141f021a95509a346abd733135b79..0da93dbbd0c8a6a91e1aeaa560c181a4f5ddcdff 100644 (file)
--- a/drivers/net/ethernet/broadcom/tg3.c
+++ b/drivers/net/ethernet/broadcom/tg3.c
@@ -5928,6 +5928,9 @@ next_pkt_nopost:
 
        /* Refill RX ring(s). */
        if (!tg3_flag(tp, ENABLE_RSS)) {
+               /* Sync BD data before updating mailbox */
+               wmb();
+
                if (work_mask & RXD_OPAQUE_RING_STD) {
                        tpr->rx_std_prod_idx = std_prod_idx &
                                               tp->rx_std_ring_mask;
@@ -6970,6 +6973,9 @@ static netdev_tx_t tg3_start_xmit(struct sk_buff *skb, struct net_device *dev)
        skb_tx_timestamp(skb);
        netdev_sent_queue(tp->dev, skb->len);
 
+       /* Sync BD data before updating mailbox */
+       wmb();
+
        /* Packets are ready, update Tx producer idx local and on card. */
        tw32_tx_mbox(tnapi->prodmbox, entry);
 
@@ -11763,6 +11769,9 @@ static int tg3_run_loopback(struct tg3 *tp, u32 pktsz, bool tso_loopback)
 
        tnapi->tx_prod++;
 
+       /* Sync BD data before updating mailbox */
+       wmb();
+
        tw32_tx_mbox(tnapi->prodmbox, tnapi->tx_prod);
        tr32_mailbox(tnapi->prodmbox);