From: Jongsung Kim neidhard.kim@lge.com
commit f421031e3ff0dd288a6e1bbde9aa41a25bb814e6 upstream.
Refer to the databook of DesignWare Cores Ethernet MAC Universal:
6.2.1.5 Register 4 (Transmit Descriptor List Address Register
If this register is not changed when the ST bit is set to 0, then the DMA takes the descriptor address where it was stopped earlier.
The stmmac_tx_err() does zero indices to Tx descriptors, but does not reset HW current Tx descriptor address. To fix inconsistency, the base address of the Tx descriptors should be rewritten before restarting Tx.
Signed-off-by: Jongsung Kim neidhard.kim@lge.com Signed-off-by: David S. Miller davem@davemloft.net Cc: Macpaul Lin macpaul.lin@mediatek.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/net/ethernet/stmicro/stmmac/stmmac_main.c | 2 ++ 1 file changed, 2 insertions(+)
--- a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c +++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c @@ -1987,6 +1987,8 @@ static void stmmac_tx_err(struct stmmac_ tx_q->cur_tx = 0; tx_q->mss = 0; netdev_tx_reset_queue(netdev_get_tx_queue(priv->dev, chan)); + stmmac_init_tx_chan(priv, priv->ioaddr, priv->plat->dma_cfg, + tx_q->dma_tx_phy, chan); stmmac_start_tx_dma(priv, chan);
priv->dev->stats.tx_errors++;