+static int sparx5_port_open(struct net_device *ndev)
+{
+	struct sparx5_port *port = netdev_priv(ndev);
+	int err = 0;
+
+	sparx5_port_enable(port, true);
+	if (port->conf.phy_mode != PHY_INTERFACE_MODE_NA) {
+		err = phylink_of_phy_connect(port->phylink, port->of_node, 0);
+		if (err) {
+			netdev_err(ndev, "Could not attach to PHY\n");
+			return err;
+		}
+	}

This looks a bit odd. PHY_INTERFACE_MODE_NA means don't touch,
something else has already configured the MAC-PHY mode in the PHY.
You should not not connect the PHY because of this.

+void sparx5_destroy_netdev(struct sparx5 *sparx5, struct sparx5_port *port)
+{
+	if (port->phylink) {
+		/* Disconnect the phy */
+		if (rtnl_trylock()) {

Why do you use rtnl_trylock()?

    Andrew