stmmac: Stop advertising 1000Base capabilties for non GMII iface (V4).

This patch stops advertising 1000Base capablities if GMAC is either
configured for MII or RMII mode and on board there is a GPHY plugged on.
Without this patch if an GBit switch is connected on MII interface,
Ethernet stops working at all.

Discovered as part of
https://bugzilla.stlinux.com/show_bug.cgi?id=14148 triage

Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@st.com>
Signed-off-by: Giuseppe Cavallaro <peppe.cavallaro@st.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
index 87a6b2e..ae5debb 100644 (file)
--- a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
+++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
@@ -304,7 +304,7 @@ static int stmmac_init_phy(struct net_device *dev)
        struct phy_device *phydev;
        char phy_id[MII_BUS_ID_SIZE + 3];
        char bus_id[MII_BUS_ID_SIZE];
-
+       int interface = priv->plat->interface;
        priv->oldlink = 0;
        priv->speed = 0;
        priv->oldduplex = -1;
@@ -314,14 +314,21 @@ static int stmmac_init_phy(struct net_device *dev)
                 priv->plat->phy_addr);
        pr_debug("stmmac_init_phy:  trying to attach to %s\n", phy_id);
 
-       phydev = phy_connect(dev, phy_id, &stmmac_adjust_link, 0,
-                            priv->plat->interface);
+       phydev = phy_connect(dev, phy_id, &stmmac_adjust_link, 0, interface);
 
        if (IS_ERR(phydev)) {
                pr_err("%s: Could not attach to PHY\n", dev->name);
                return PTR_ERR(phydev);
        }
 
+       /* Stop Advertising 1000BASE Capability if interface is not GMII */
+       if ((interface) && ((interface == PHY_INTERFACE_MODE_MII) ||
+           (interface == PHY_INTERFACE_MODE_RMII))) {
+               phydev->supported &= (PHY_BASIC_FEATURES | SUPPORTED_Pause |
+                                     SUPPORTED_Asym_Pause);
+               priv->phydev->advertising = priv->phydev->supported;
+       }
+
        /*
         * Broken HW is sometimes missing the pull-up resistor on the
         * MDIO line, which results in reads to non-existent devices returning