stmmac: hardware TX COE doesn't work when force_thresh_dma_mode is set

Clear the TX COE bit when force_thresh_dma_mode is set even hardware
dma capability says support.

Tested on BF609.

Signed-off-by: Sonic Zhang <sonic.zhang@analog.com>
Acked-by: Giuseppe Cavallaro <peppe.cavallaro@st.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 5 insertions, 1 deletions

diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
index 6e2a8fa07da5..5ef493aa5387 100644
--- a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
+++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
@@ -2755,7 +2755,11 @@ static int stmmac_hw_init(struct stmmac_priv *priv)
                 priv->plat->enh_desc = priv->dma_cap.enh_desc;
                 priv->plat->pmt = priv->dma_cap.pmt_remote_wake_up;
 
-                priv->plat->tx_coe = priv->dma_cap.tx_coe;
+                /* TXCOE doesn't work in thresh DMA mode */
+                if (priv->plat->force_thresh_dma_mode)
+                        priv->plat->tx_coe = 0;
+                else
+                        priv->plat->tx_coe = priv->dma_cap.tx_coe;
 
                 if (priv->dma_cap.rx_coe_type2)
                         priv->plat->rx_coe = STMMAC_RX_COE_TYPE2;