diff options
| author | Lars Persson <lars.persson@axis.com> | 2019-04-15 09:50:34 +0200 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2019-04-20 09:07:54 +0200 |
| commit | b142075137c31c1009069f01d6882c06cf760156 (patch) | |
| tree | 37c1290fd1470433a24c10a9ec59c71319b2e1b9 | |
| parent | b6178400e55080fd1fcf3ddbfd2e5c61b83c6421 (diff) | |
net: stmmac: Set dma ring length before enabling the DMA
This was fixed in upstream by commit 7d9e6c5afab6 ("net: stmmac: Integrate
XGMAC into main driver flow") that is a new feature commit.
We found a race condition in the DMA init sequence that hits if the
PHY already has link up during stmmac_hw_setup. Since the ring length
was programmed after enabling the RX path, we might receive a packet
before the correct ring length is programmed. When that happened we
could not get reliable interrupts for DMA RX and the MTL complained
about RX FIFO overrun.
Signed-off-by: Lars Persson <larper@axis.com>
Cc: stable@vger.kernel.org # 4.9.x
Cc: Giuseppe Cavallaro <peppe.cavallaro@st.com>
Cc: Alexandre Torgue <alexandre.torgue@st.com>
Cc: Jose Abreu <joabreu@synopsys.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| -rw-r--r-- | drivers/net/ethernet/stmicro/stmmac/stmmac_main.c | 10 |
1 files changed, 5 insertions, 5 deletions
diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c index fc437d75ac76..b46b56ad7517 100644 --- a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c +++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c @@ -1747,11 +1747,6 @@ static int stmmac_hw_setup(struct net_device *dev, bool init_ptp) if (ret < 0) pr_warn("%s: failed debugFS registration\n", __func__); #endif - /* Start the ball rolling... */ - pr_debug("%s: DMA RX/TX processes started...\n", dev->name); - priv->hw->dma->start_tx(priv->ioaddr); - priv->hw->dma->start_rx(priv->ioaddr); - /* Dump DMA/MAC registers */ if (netif_msg_hw(priv)) { priv->hw->mac->dump_regs(priv->hw); @@ -1779,6 +1774,11 @@ static int stmmac_hw_setup(struct net_device *dev, bool init_ptp) if (priv->tso) priv->hw->dma->enable_tso(priv->ioaddr, 1, STMMAC_CHAN0); + /* Start the ball rolling... */ + pr_debug("%s: DMA RX/TX processes started...\n", dev->name); + priv->hw->dma->start_tx(priv->ioaddr); + priv->hw->dma->start_rx(priv->ioaddr); + return 0; } |