When in AVB mode we need to disable flow control to prevent MAC from
pausing in TX side.
Fixes: ec6ea8e3eee9 ("net: stmmac: Add CBS support in XGMAC2")
Signed-off-by: Jose Abreu <Jose.Abreu@synopsys.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
 static void dwxgmac2_qmode(void __iomem *ioaddr, u32 channel, u8 qmode)
 {
        u32 value = readl(ioaddr + XGMAC_MTL_TXQ_OPMODE(channel));
+       u32 flow = readl(ioaddr + XGMAC_RX_FLOW_CTRL);
 
        value &= ~XGMAC_TXQEN;
        if (qmode != MTL_QUEUE_AVB) {
                writel(0, ioaddr + XGMAC_MTL_TCx_ETS_CONTROL(channel));
        } else {
                value |= 0x1 << XGMAC_TXQEN_SHIFT;
+               writel(flow & (~XGMAC_RFE), ioaddr + XGMAC_RX_FLOW_CTRL);
        }
 
        writel(value, ioaddr +  XGMAC_MTL_TXQ_OPMODE(channel));