+	priv->phy_np = of_parse_phandle(pdev->dev.of_node, "phy-handle", 0);
+	priv->phy_mode = of_get_phy_mode(pdev->dev.of_node);
+	/* If phy-mode absent, default to SGMII. */
+	if (priv->phy_mode < 0)
+		priv->phy_mode = PHY_INTERFACE_MODE_SGMII;
+
+	if (priv->phy_mode == PHY_INTERFACE_MODE_1000BASEX)
+		priv->mode_1000basex = true;
+
+	if (of_phy_is_fixed_link(pdev->dev.of_node))
+		priv->bgx_as_phy = true;
+

...

+	priv->mode = bgx_port_get_mode(priv->node, priv->bgx, priv->index);
+

It might be a good idea to verify priv->phy_mode and priv->mode are
compatible.

+	switch (priv->mode) {
+	case PORT_MODE_SGMII:
+	case PORT_MODE_RGMII:
+		priv->get_link = bgx_port_get_sgmii_link;
+		priv->set_link = bgx_port_set_xgmii_link;
+		break;
+	case PORT_MODE_XAUI:
+	case PORT_MODE_RXAUI:
+	case PORT_MODE_XLAUI:
+	case PORT_MODE_XFI:
+	case PORT_MODE_10G_KR:
+	case PORT_MODE_40G_KR4:
+		priv->get_link = bgx_port_get_xaui_link;
+		priv->set_link = bgx_port_set_xaui_link;
+		break;

  Andrew