net: stmmac: dwmac4: fix flow control issue

[ Upstream commit ee326fd01e79dfa42014d55931260b68b9fa3273 ]

Current dwmac4_flow_ctrl will not clear
GMAC_RX_FLOW_CTRL_RFE/GMAC_RX_FLOW_CTRL_RFE bits,
so MAC hw will keep flow control on although expecting
flow control off by ethtool. Add codes to fix it.

Fixes: 477286b53f55 ("stmmac: add GMAC4 core support")
Signed-off-by: Biao Huang <biao.huang@mediatek.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>

diff --git a/drivers/net/ethernet/stmicro/stmmac/dwmac4_core.c b/drivers/net/ethernet/stmicro/stmmac/dwmac4_core.c
index a2f3db3..d0e6e15 100644 (file)
--- a/drivers/net/ethernet/stmicro/stmmac/dwmac4_core.c
+++ b/drivers/net/ethernet/stmicro/stmmac/dwmac4_core.c
@@ -475,8 +475,9 @@ static void dwmac4_flow_ctrl(struct mac_device_info *hw, unsigned int duplex,
        if (fc & FLOW_RX) {
                pr_debug("\tReceive Flow-Control ON\n");
                flow |= GMAC_RX_FLOW_CTRL_RFE;
-               writel(flow, ioaddr + GMAC_RX_FLOW_CTRL);
        }
+       writel(flow, ioaddr + GMAC_RX_FLOW_CTRL);
+
        if (fc & FLOW_TX) {
                pr_debug("\tTransmit Flow-Control ON\n");
 
@@ -484,7 +485,7 @@ static void dwmac4_flow_ctrl(struct mac_device_info *hw, unsigned int duplex,
                        pr_debug("\tduplex mode: PAUSE %d\n", pause_time);
 
                for (queue = 0; queue < tx_cnt; queue++) {
-                       flow |= GMAC_TX_FLOW_CTRL_TFE;
+                       flow = GMAC_TX_FLOW_CTRL_TFE;
 
                        if (duplex)
                                flow |=
@@ -492,6 +493,9 @@ static void dwmac4_flow_ctrl(struct mac_device_info *hw, unsigned int duplex,
 
                        writel(flow, ioaddr + GMAC_QX_TX_FLOW_CTRL(queue));
                }
+       } else {
+               for (queue = 0; queue < tx_cnt; queue++)
+                       writel(0, ioaddr + GMAC_QX_TX_FLOW_CTRL(queue));
        }
 }