drivers/net/ethernet/faraday/ftgmac100.c | 26 ++++++++++++++++-------- 1 file changed, 18 insertions(+), 8 deletions(-)
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>
---
drivers/net/ethernet/faraday/ftgmac100.c | 26 ++++++++++++++++--------
1 file changed, 18 insertions(+), 8 deletions(-)
diff --git a/drivers/net/ethernet/faraday/ftgmac100.c b/drivers/net/ethernet/faraday/ftgmac100.c
index 93862b027be0..9c521d0af7ac 100644
--- a/drivers/net/ethernet/faraday/ftgmac100.c
+++ b/drivers/net/ethernet/faraday/ftgmac100.c
@@ -582,7 +582,7 @@ static bool ftgmac100_rx_packet(struct ftgmac100 *priv, int *processed)
(*processed)++;
return true;
- drop:
+drop:
/* Clean rxdes0 (which resets own bit) */
rxdes->rxdes0 = cpu_to_le32(status & priv->rxdes0_edorr_mask);
priv->rx_pointer = ftgmac100_next_rx_pointer(priv, pointer);
@@ -666,6 +666,11 @@ 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;
@@ -819,6 +824,11 @@ 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;
@@ -839,7 +849,7 @@ static netdev_tx_t ftgmac100_hard_start_xmit(struct sk_buff *skb,
return NETDEV_TX_OK;
- dma_err:
+dma_err:
if (net_ratelimit())
netdev_err(netdev, "map tx fragment failed\n");
@@ -861,7 +871,7 @@ static netdev_tx_t ftgmac100_hard_start_xmit(struct sk_buff *skb,
* last fragment, so we know ftgmac100_free_tx_packet()
* hasn't freed the skb yet.
*/
- drop:
+drop:
/* Drop the packet */
dev_kfree_skb_any(skb);
netdev->stats.tx_dropped++;
@@ -1354,7 +1364,7 @@ static void ftgmac100_reset(struct ftgmac100 *priv)
ftgmac100_init_all(priv, true);
netdev_dbg(netdev, "Reset done !\n");
- bail:
+bail:
if (priv->mii_bus)
mutex_unlock(&priv->mii_bus->mdio_lock);
if (netdev->phydev)
@@ -1554,15 +1564,15 @@ static int ftgmac100_open(struct net_device *netdev)
return 0;
- err_ncsi:
+err_ncsi:
napi_disable(&priv->napi);
netif_stop_queue(netdev);
- err_alloc:
+err_alloc:
ftgmac100_free_buffers(priv);
free_irq(netdev->irq, netdev);
- err_irq:
+err_irq:
netif_napi_del(&priv->napi);
- err_hw:
+err_hw:
iowrite32(0, priv->base + FTGMAC100_OFFSET_IER);
ftgmac100_free_rings(priv);
return err;
--
2.25.1On Thu, 22 Aug 2024 at 17:00, Jacky Chou <jacky_chou@aspeedtech.com> wrote: > > 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. Thanks for re-submitting my patch and getting it merged. In the future, it would be best if you left the authorship, and preserved my commit message. https://lore.kernel.org/all/20201020220639.130696-1-joel@jms.id.au/ Cheers, Joel > > Signed-off-by: Jacky Chou <jacky_chou@aspeedtech.com> > --- > drivers/net/ethernet/faraday/ftgmac100.c | 26 ++++++++++++++++-------- > 1 file changed, 18 insertions(+), 8 deletions(-) > > diff --git a/drivers/net/ethernet/faraday/ftgmac100.c b/drivers/net/ethernet/faraday/ftgmac100.c > index 93862b027be0..9c521d0af7ac 100644 > --- a/drivers/net/ethernet/faraday/ftgmac100.c > +++ b/drivers/net/ethernet/faraday/ftgmac100.c > @@ -582,7 +582,7 @@ static bool ftgmac100_rx_packet(struct ftgmac100 *priv, int *processed) > (*processed)++; > return true; > > - drop: > +drop: > /* Clean rxdes0 (which resets own bit) */ > rxdes->rxdes0 = cpu_to_le32(status & priv->rxdes0_edorr_mask); > priv->rx_pointer = ftgmac100_next_rx_pointer(priv, pointer); > @@ -666,6 +666,11 @@ 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; > @@ -819,6 +824,11 @@ 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; > > @@ -839,7 +849,7 @@ static netdev_tx_t ftgmac100_hard_start_xmit(struct sk_buff *skb, > > return NETDEV_TX_OK; > > - dma_err: > +dma_err: > if (net_ratelimit()) > netdev_err(netdev, "map tx fragment failed\n"); > > @@ -861,7 +871,7 @@ static netdev_tx_t ftgmac100_hard_start_xmit(struct sk_buff *skb, > * last fragment, so we know ftgmac100_free_tx_packet() > * hasn't freed the skb yet. > */ > - drop: > +drop: > /* Drop the packet */ > dev_kfree_skb_any(skb); > netdev->stats.tx_dropped++; > @@ -1354,7 +1364,7 @@ static void ftgmac100_reset(struct ftgmac100 *priv) > ftgmac100_init_all(priv, true); > > netdev_dbg(netdev, "Reset done !\n"); > - bail: > +bail: > if (priv->mii_bus) > mutex_unlock(&priv->mii_bus->mdio_lock); > if (netdev->phydev) > @@ -1554,15 +1564,15 @@ static int ftgmac100_open(struct net_device *netdev) > > return 0; > > - err_ncsi: > +err_ncsi: > napi_disable(&priv->napi); > netif_stop_queue(netdev); > - err_alloc: > +err_alloc: > ftgmac100_free_buffers(priv); > free_irq(netdev->irq, netdev); > - err_irq: > +err_irq: > netif_napi_del(&priv->napi); > - err_hw: > +err_hw: > iowrite32(0, priv->base + FTGMAC100_OFFSET_IER); > ftgmac100_free_rings(priv); > return err; > -- > 2.25.1 > >
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