net: stmmac: Limit max speeds of XGMAC if asked to

We may have some SoCs that can't achieve XGMAC max speed. Limit it if
asked to.
Signed-off-by: Jose Abreu <joabreu@synopsys.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/stmicro/stmmac/stmmac_main.c

@@ -831,8 +831,14 @@ static void stmmac_validate(struct phylink_config *config,
 		phylink_set(mask, 1000baseT_Full);
 		phylink_set(mask, 1000baseX_Full);
 	} else if (priv->plat->has_xgmac) {
+		if (!max_speed || (max_speed >= 2500)) {
 			phylink_set(mac_supported, 2500baseT_Full);
+			phylink_set(mac_supported, 2500baseX_Full);
+		}
+		if (!max_speed || (max_speed >= 5000)) {
 			phylink_set(mac_supported, 5000baseT_Full);
+		}
+		if (!max_speed || (max_speed >= 10000)) {
 			phylink_set(mac_supported, 10000baseSR_Full);
 			phylink_set(mac_supported, 10000baseLR_Full);
 			phylink_set(mac_supported, 10000baseER_Full);
@@ -841,6 +847,7 @@ static void stmmac_validate(struct phylink_config *config,
 			phylink_set(mac_supported, 10000baseKX4_Full);
 			phylink_set(mac_supported, 10000baseKR_Full);
 		}
+	}
 
 	/* Half-Duplex can only work with single queue */
 	if (tx_cnt > 1) {