Commit 176eaa58 authored by Andreas Oberritter's avatar Andreas Oberritter Committed by David S. Miller

8139too: move wmb before TX DMA start

The write barrier should be used before starting a DMA transfer. This fixes
a problem, where almost all packets received on another machine had garbled
content. Tested with an RTL8100C on a MIPS machine.
Signed-off-by: default avatarAndreas Oberritter <obi@linuxtv.org>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent ed4cb133
......@@ -1723,13 +1723,18 @@ static int rtl8139_start_xmit (struct sk_buff *skb, struct net_device *dev)
}
spin_lock_irqsave(&tp->lock, flags);
/*
* Writing to TxStatus triggers a DMA transfer of the data
* copied to tp->tx_buf[entry] above. Use a memory barrier
* to make sure that the device sees the updated data.
*/
wmb();
RTL_W32_F (TxStatus0 + (entry * sizeof (u32)),
tp->tx_flag | max(len, (unsigned int)ETH_ZLEN));
dev->trans_start = jiffies;
tp->cur_tx++;
wmb();
if ((tp->cur_tx - NUM_TX_DESC) == tp->dirty_tx)
netif_stop_queue (dev);
......
Markdown is supported
0% or .
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment