net: dsa: bcm_sf2: Do not configure PHYLINK on CPU port

The SF2 binding does not specify that the CPU port should have
properties mandatory for successfully instantiating a PHYLINK object. As
such, there will be missing properties (including fixed-link) and when
attempting to validate and later configure link modes, we will have an
incorrect set of parameters (interface, speed, duplex).

Simply prevent the CPU port from being configured through PHYLINK since
bcm_sf2_imp_setup() takes care of that already.

Fixes: 0e279218 ("net: dsa: Use PHYLINK for the CPU/DSA ports")
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/dsa/bcm_sf2.c

@@ -478,6 +478,7 @@ static void bcm_sf2_sw_validate(struct dsa_switch *ds, int port,
 				unsigned long *supported,
 				struct phylink_link_state *state)
 {
+	struct bcm_sf2_priv *priv = bcm_sf2_to_priv(ds);
 	__ETHTOOL_DECLARE_LINK_MODE_MASK(mask) = { 0, };
 
 	if (!phy_interface_mode_is_rgmii(state->interface) &&
@@ -487,8 +488,10 @@ static void bcm_sf2_sw_validate(struct dsa_switch *ds, int port,
 	    state->interface != PHY_INTERFACE_MODE_INTERNAL &&
 	    state->interface != PHY_INTERFACE_MODE_MOCA) {
 		bitmap_zero(supported, __ETHTOOL_LINK_MODE_MASK_NBITS);
-		dev_err(ds->dev,
-			"Unsupported interface: %d\n", state->interface);
+		if (port != core_readl(priv, CORE_IMP0_PRT_ID))
+			dev_err(ds->dev,
+				"Unsupported interface: %d for port %d\n",
+				state->interface, port);
 		return;
 	}
 
@@ -526,6 +529,9 @@ static void bcm_sf2_sw_mac_config(struct dsa_switch *ds, int port,
 	u32 id_mode_dis = 0, port_mode;
 	u32 reg, offset;
 
+	if (port == core_readl(priv, CORE_IMP0_PRT_ID))
+		return;
+
 	if (priv->type == BCM7445_DEVICE_ID)
 		offset = CORE_STS_OVERRIDE_GMIIP_PORT(port);
 	else