drivers: net: aquantia: use XFI, USXGMII interface types

The PHY supports XFI and USXGMII, the notable difference being that USX AN
is enabled for USXGMII.  Legacy code uses XGMII for any 10G proto and
detects whether USX AN should be enabled or not using a PHY status
register.  Keep that functionality too, so we don't break existing drivers.

Signed-off-by: Razvan Ionut Cirjan <razvanionut.cirjan@nxp.com>
Signed-off-by: Alex Marginean <alexandru.marginean@nxp.com>
Acked-by: Joe Hershberger <joe.hershberger@ni.com>
diff --git a/drivers/net/phy/aquantia.c b/drivers/net/phy/aquantia.c
index 1061fdf..601121d 100644
--- a/drivers/net/phy/aquantia.c
+++ b/drivers/net/phy/aquantia.c
@@ -259,9 +259,11 @@
 
 int aquantia_config(struct phy_device *phydev)
 {
+	int interface = phydev->interface;
 	u32 val, id, rstatus, fault;
 	u32 reg_val1 = 0;
 	int num_retries = 5;
+	int usx_an = 0;
 
 	/*
 	 * check if the system is out of reset and init sequence completed.
@@ -293,17 +295,34 @@
 		if (ret != 0)
 			return ret;
 	}
+	/*
+	 * for backward compatibility convert XGMII into either XFI or USX based
+	 * on FW config
+	 */
+	if (interface == PHY_INTERFACE_MODE_XGMII) {
+		reg_val1 = phy_read(phydev, MDIO_MMD_PHYXS,
+				    AQUANTIA_SYSTEM_INTERFACE_SR);
+		if ((reg_val1 & AQUANTIA_SI_IN_USE_MASK) == AQUANTIA_SI_USXGMII)
+			interface = PHY_INTERFACE_MODE_USXGMII;
+		else
+			interface = PHY_INTERFACE_MODE_XFI;
+	}
 
 	val = phy_read(phydev, MDIO_MMD_PMAPMD, MII_BMCR);
 
-	if (phydev->interface == PHY_INTERFACE_MODE_SGMII) {
+	switch (interface) {
+	case PHY_INTERFACE_MODE_SGMII:
 		/* 1000BASE-T mode */
 		phydev->advertising = SUPPORTED_1000baseT_Full;
 		phydev->supported = phydev->advertising;
 
 		val = (val & ~AQUNTIA_SPEED_LSB_MASK) | AQUNTIA_SPEED_MSB_MASK;
 		phy_write(phydev, MDIO_MMD_PMAPMD, MII_BMCR, val);
-	} else if (phydev->interface == PHY_INTERFACE_MODE_XGMII) {
+		break;
+	case PHY_INTERFACE_MODE_USXGMII:
+		usx_an = 1;
+		/* FALLTHROUGH */
+	case PHY_INTERFACE_MODE_XFI:
 		/* 10GBASE-T mode */
 		phydev->advertising = SUPPORTED_10000baseT_Full;
 		phydev->supported = phydev->advertising;
@@ -314,40 +333,40 @@
 				  AQUNTIA_SPEED_LSB_MASK |
 				  AQUNTIA_SPEED_MSB_MASK);
 
-		val = phy_read(phydev, MDIO_MMD_PHYXS,
-			       AQUANTIA_SYSTEM_INTERFACE_SR);
 		/* If SI is USXGMII then start USXGMII autoneg */
-		if ((val & AQUANTIA_SI_IN_USE_MASK) == AQUANTIA_SI_USXGMII) {
-			reg_val1 =  phy_read(phydev, MDIO_MMD_PHYXS,
-					     AQUANTIA_VENDOR_PROVISIONING_REG);
+		reg_val1 =  phy_read(phydev, MDIO_MMD_PHYXS,
+				     AQUANTIA_VENDOR_PROVISIONING_REG);
 
+		if (usx_an) {
 			reg_val1 |= AQUANTIA_USX_AUTONEG_CONTROL_ENA;
-
-			phy_write(phydev, MDIO_MMD_PHYXS,
-				  AQUANTIA_VENDOR_PROVISIONING_REG,
-				  reg_val1);
 			printf("%s: system interface USXGMII\n",
 			       phydev->dev->name);
 		} else {
+			reg_val1 &= ~AQUANTIA_USX_AUTONEG_CONTROL_ENA;
 			printf("%s: system interface XFI\n",
 			       phydev->dev->name);
 		}
 
-	} else if (phydev->interface == PHY_INTERFACE_MODE_SGMII_2500) {
+		phy_write(phydev, MDIO_MMD_PHYXS,
+			  AQUANTIA_VENDOR_PROVISIONING_REG, reg_val1);
+		break;
+	case PHY_INTERFACE_MODE_SGMII_2500:
 		/* 2.5GBASE-T mode */
 		phydev->advertising = SUPPORTED_1000baseT_Full;
 		phydev->supported = phydev->advertising;
 
 		phy_write(phydev, MDIO_MMD_AN, AQUNTIA_10G_CTL, 1);
 		phy_write(phydev, MDIO_MMD_AN, AQUNTIA_VENDOR_P1, 0x9440);
-	} else if (phydev->interface == PHY_INTERFACE_MODE_MII) {
+		break;
+	case PHY_INTERFACE_MODE_MII:
 		/* 100BASE-TX mode */
 		phydev->advertising = SUPPORTED_100baseT_Full;
 		phydev->supported = phydev->advertising;
 
 		val = (val & ~AQUNTIA_SPEED_MSB_MASK) | AQUNTIA_SPEED_LSB_MASK;
 		phy_write(phydev, MDIO_MMD_PMAPMD, MII_BMCR, val);
-	}
+		break;
+	};
 
 	val = phy_read(phydev, MDIO_MMD_VEND1, AQUANTIA_RESERVED_STATUS);
 	reg_val1 = phy_read(phydev, MDIO_MMD_VEND1, AQUANTIA_FIRMWARE_ID);