macb: restore wrap bit when performing underrun cleanup

When TX underrun occurs, a cleanup is performed that marks all buffers
as used. As a side effect it also clears the wrap bit in the last
buffer. This patch will restore the wrap bit.

Signed-off-by: Tord Andersson <tord.andersson@endian.se>
Acked-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 3 insertions, 0 deletions

diff --git a/drivers/net/macb.c b/drivers/net/macb.c
index 0fcdc25699d8..dc4e305a1087 100644
--- a/drivers/net/macb.c
+++ b/drivers/net/macb.c
@@ -322,6 +322,9 @@ static void macb_tx(struct macb *bp)
                 for (i = 0; i < TX_RING_SIZE; i++)
                         bp->tx_ring[i].ctrl = MACB_BIT(TX_USED);
 
+                /* Add wrap bit */
+                bp->tx_ring[TX_RING_SIZE - 1].ctrl |= MACB_BIT(TX_WRAP);
+
                 /* free transmit buffer in upper layer*/
                 for (tail = bp->tx_tail; tail != head; tail = NEXT_TX(tail)) {
                         struct ring_info *rp = &bp->tx_skb[tail];