net: ftgmac100: Ensure tx descriptor updates are visible

The driver must ensure TX descriptor updates are visible
before updating TX pointer and TX clear pointer.

This resolves TX hangs observed on AST2600 when running
iperf3.

Signed-off-by: Jacky Chou <jacky_chou@aspeedtech.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Jacky Chou 2024-08-22 15:30:06 +08:00 committed by David S. Miller
parent 8af174ea86
commit 4186c8d9e6

View file

@ -656,6 +656,11 @@ static bool ftgmac100_tx_complete_packet(struct ftgmac100 *priv)
ftgmac100_free_tx_packet(priv, pointer, skb, txdes, ctl_stat);
txdes->txdes0 = cpu_to_le32(ctl_stat & priv->txdes0_edotr_mask);
/* Ensure the descriptor config is visible before setting the tx
* pointer.
*/
smp_wmb();
priv->tx_clean_pointer = ftgmac100_next_tx_pointer(priv, pointer);
return true;
@ -809,6 +814,11 @@ static netdev_tx_t ftgmac100_hard_start_xmit(struct sk_buff *skb,
dma_wmb();
first->txdes0 = cpu_to_le32(f_ctl_stat);
/* Ensure the descriptor config is visible before setting the tx
* pointer.
*/
smp_wmb();
/* Update next TX pointer */
priv->tx_pointer = pointer;