stmmac: fix DMA channel hang in half-duplex mode

HW does not support Half-duplex mode in multi-queue
scenario. Fix it by not advertising the Half-Duplex
mode if multi-queue enabled.

Signed-off-by: Bhadram Varka <vbhadram@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 10 insertions, 0 deletions

diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
index e79b0d7b388a..cba46b62a1cd 100644
--- a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
+++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
@@ -928,6 +928,7 @@ static void stmmac_check_pcs_mode(struct stmmac_priv *priv)
 static int stmmac_init_phy(struct net_device *dev)
 {
         struct stmmac_priv *priv = netdev_priv(dev);
+        u32 tx_cnt = priv->plat->tx_queues_to_use;
         struct phy_device *phydev;
         char phy_id_fmt[MII_BUS_ID_SIZE + 3];
         char bus_id[MII_BUS_ID_SIZE];
@@ -969,6 +970,15 @@ static int stmmac_init_phy(struct net_device *dev)
                                          SUPPORTED_1000baseT_Full);
 
         /*
+         * Half-duplex mode not supported with multiqueue
+         * half-duplex can only works with single queue
+         */
+        if (tx_cnt > 1)
+                phydev->supported &= ~(SUPPORTED_1000baseT_Half |
+                                       SUPPORTED_100baseT_Half |
+                                       SUPPORTED_10baseT_Half);
+
+        /*
          * Broken HW is sometimes missing the pull-up resistor on the
          * MDIO line, which results in reads to non-existent devices returning
          * 0 rather than 0xffff. Catch this here and treat 0 as a non-existent