amd-xgbe: Fix initial mode when auto-negotiation is disabled

When the ethtool command is used to set the speed of the device while
the device is down, the check to set the initial mode may fail when
the device is brought up, causing failure to bring the device up.

Update the code to set the initial mode based on the desired speed if
auto-negotiation is disabled.

Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/drivers/net/ethernet/amd/xgbe/xgbe-mdio.c b/drivers/net/ethernet/amd/xgbe/xgbe-mdio.c
index cea19a3..8b86d94 100644
--- a/drivers/net/ethernet/amd/xgbe/xgbe-mdio.c
+++ b/drivers/net/ethernet/amd/xgbe/xgbe-mdio.c
@@ -376,6 +376,45 @@
 		xgbe_switch_mode(pdata);
 }
 
+static bool xgbe_use_xgmii_mode(struct xgbe_prv_data *pdata)
+{
+	if (pdata->phy.autoneg == AUTONEG_ENABLE) {
+		if (pdata->phy.advertising & ADVERTISED_10000baseKR_Full)
+			return true;
+	} else {
+		if (pdata->phy.speed == SPEED_10000)
+			return true;
+	}
+
+	return false;
+}
+
+static bool xgbe_use_gmii_2500_mode(struct xgbe_prv_data *pdata)
+{
+	if (pdata->phy.autoneg == AUTONEG_ENABLE) {
+		if (pdata->phy.advertising & ADVERTISED_2500baseX_Full)
+			return true;
+	} else {
+		if (pdata->phy.speed == SPEED_2500)
+			return true;
+	}
+
+	return false;
+}
+
+static bool xgbe_use_gmii_mode(struct xgbe_prv_data *pdata)
+{
+	if (pdata->phy.autoneg == AUTONEG_ENABLE) {
+		if (pdata->phy.advertising & ADVERTISED_1000baseKX_Full)
+			return true;
+	} else {
+		if (pdata->phy.speed == SPEED_1000)
+			return true;
+	}
+
+	return false;
+}
+
 static void xgbe_set_an(struct xgbe_prv_data *pdata, bool enable, bool restart)
 {
 	unsigned int reg;
@@ -1108,11 +1147,11 @@
 	/* Set initial mode - call the mode setting routines
 	 * directly to insure we are properly configured
 	 */
-	if (pdata->phy.advertising & ADVERTISED_10000baseKR_Full) {
+	if (xgbe_use_xgmii_mode(pdata)) {
 		xgbe_xgmii_mode(pdata);
-	} else if (pdata->phy.advertising & ADVERTISED_1000baseKX_Full) {
+	} else if (xgbe_use_gmii_mode(pdata)) {
 		xgbe_gmii_mode(pdata);
-	} else if (pdata->phy.advertising & ADVERTISED_2500baseX_Full) {
+	} else if (xgbe_use_gmii_2500_mode(pdata)) {
 		xgbe_gmii_2500_mode(pdata);
 	} else {
 		ret = -EINVAL;