From: Jacky Chou <jacky_chou@xxxxxxxxxxxxxx> [ Upstream commit 4186c8d9e6af57bab0687b299df10ebd47534a0a ] 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@xxxxxxxxxxxxxx> Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- 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 a03879a27b041..7adc46aa75e66 100644 --- a/drivers/net/ethernet/faraday/ftgmac100.c +++ b/drivers/net/ethernet/faraday/ftgmac100.c @@ -566,7 +566,7 @@ 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); @@ -650,6 +650,11 @@ 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; @@ -803,6 +808,11 @@ 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; @@ -823,7 +833,7 @@ 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"); @@ -845,7 +855,7 @@ 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++; @@ -1338,7 +1348,7 @@ 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) @@ -1537,15 +1547,15 @@ 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; -- 2.43.0
