net: stmmac: split xPCS setup from mdio register

This patch is a preparation patch for the enabling of Intel mGbE 2.5Gbps
link speed. The Intel mGbR link speed configuration (1G/2.5G) is depends on
a mdio ADHOC register which can be configured in the bios menu.
As PHY interface might be different for 1G and 2.5G, the mdio bus need be
ready to check the link speed and select the PHY interface before probing
the xPCS.

Signed-off-by: Voon Weifeng <weifeng.voon@intel.com>
Signed-off-by: Michael Sit Wei Hong <michael.wei.hong.sit@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/stmicro/stmmac/stmmac.h

@@ -311,6 +311,7 @@ enum stmmac_state {
 int stmmac_mdio_unregister(struct net_device *ndev);
 int stmmac_mdio_register(struct net_device *ndev);
 int stmmac_mdio_reset(struct mii_bus *mii);
+int stmmac_xpcs_setup(struct mii_bus *mii);
 void stmmac_set_ethtool_ops(struct net_device *netdev);
 
 void stmmac_ptp_register(struct stmmac_priv *priv);

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

@@ -6993,6 +6993,14 @@ int stmmac_dvr_probe(struct device *device,
 		}
 	}
 
+	if (priv->plat->mdio_bus_data) {
+		if (priv->plat->mdio_bus_data->has_xpcs) {
+			ret = stmmac_xpcs_setup(priv->mii);
+			if (ret)
+				goto error_xpcs_setup;
+		}
+	}
+
 	ret = stmmac_phy_setup(priv);
 	if (ret) {
 		netdev_err(ndev, "failed to setup phy (%d)\n", ret);
@@ -7029,6 +7037,7 @@ int stmmac_dvr_probe(struct device *device,
 	unregister_netdev(ndev);
 error_netdev_register:
 	phylink_destroy(priv->phylink);
+error_xpcs_setup:
 error_phy_setup:
 	if (priv->hw->pcs != STMMAC_PCS_TBI &&
 	    priv->hw->pcs != STMMAC_PCS_RTBI)

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

@@ -397,6 +397,41 @@ int stmmac_mdio_reset(struct mii_bus *bus)
 	return 0;
 }
 
+int stmmac_xpcs_setup(struct mii_bus *bus)
+{
+	int mode, addr;
+	struct net_device *ndev = bus->priv;
+	struct mdio_xpcs_args *xpcs;
+	struct stmmac_priv *priv;
+	struct mdio_device *mdiodev;
+
+	priv = netdev_priv(ndev);
+	mode = priv->plat->phy_interface;
+
+	/* Try to probe the XPCS by scanning all addresses. */
+	for (addr = 0; addr < PHY_MAX_ADDR; addr++) {
+		mdiodev = mdio_device_create(bus, addr);
+		if (IS_ERR(mdiodev))
+			continue;
+
+		xpcs = xpcs_create(mdiodev, mode);
+		if (IS_ERR_OR_NULL(xpcs)) {
+			mdio_device_free(mdiodev);
+			continue;
+		}
+
+		priv->hw->xpcs = xpcs;
+		break;
+	}
+
+	if (!priv->hw->xpcs) {
+		dev_warn(priv->device, "No xPCS found\n");
+		return -ENODEV;
+	}
+
+	return 0;
+}
+
 /**
  * stmmac_mdio_register
  * @ndev: net device structure
@@ -501,40 +536,11 @@ int stmmac_mdio_register(struct net_device *ndev)
 		goto no_phy_found;
 	}
 
-	/* Try to probe the XPCS by scanning all addresses. */
-	if (mdio_bus_data->has_xpcs) {
-		int mode = priv->plat->phy_interface;
-		struct mdio_device *mdiodev;
-		struct mdio_xpcs_args *xpcs;
-
-		for (addr = 0; addr < PHY_MAX_ADDR; addr++) {
-			mdiodev = mdio_device_create(new_bus, addr);
-			if (IS_ERR(mdiodev))
-				continue;
-
-			xpcs = xpcs_create(mdiodev, mode);
-			if (IS_ERR_OR_NULL(xpcs)) {
-				mdio_device_free(mdiodev);
-				continue;
-			}
-
-			priv->hw->xpcs = xpcs;
-			break;
-		}
-
-		if (!priv->hw->xpcs) {
-			dev_warn(dev, "No XPCS found\n");
-			err = -ENODEV;
-			goto no_xpcs_found;
-		}
-	}
-
 bus_register_done:
 	priv->mii = new_bus;
 
 	return 0;
 
-no_xpcs_found:
 no_phy_found:
 	mdiobus_unregister(new_bus);
 bus_register_fail: