net: enetc: add port MDIO support for ENETC v4

The NETC IP provides two ways for ENETC to access its external PHY. One
is that EMDIO function provides a means for different ENETCs to share a
single set of MDIO signals to access their PHYs. And this EMDIO support
has been added in the commit a52201f ("net: enetc: add i.MX95 EMDIO
support"). The other one is that each ENETC has a set of MDIO registers
to access and control its PHY. When the PHY node is a child node of the
ENETC node, the ENETC will use its port MDIO to access its external PHY.

For the on-die PHY (PCS/Serdes), each ENETC has an internal MDIO bus for
managing the on-die PHY, this internal MDIO bus is controlled by a set
of internal MDIO registers of the ENETC port.

Because the port MDIO support has been added to the driver for ENETC v1.
The difference between ENETC v4 and ENETC v1 is the base address of the
MDIO registers, so we only need to add the new base address to add the
port MDIO support for ENETC v4.

Signed-off-by: Wei Fang <wei.fang@nxp.com>
Signed-off-by: NipaLocal <nipa@local>

Author: Wei Fang

drivers/net/ethernet/freescale/enetc/enetc4_hw.h

@@ -170,6 +170,9 @@
 /* Port MAC 0/1 Maximum Frame Length Register */
 #define ENETC4_PM_MAXFRM(mac)		(0x5014 + (mac) * 0x400)
 
+/* Port internal MDIO base address, use to access PCS */
+#define ENETC4_PM_IMDIO_BASE		0x5030
+
 /* Port MAC 0/1 Pause Quanta Register */
 #define ENETC4_PM_PAUSE_QUANTA(mac)	(0x5054 + (mac) * 0x400)
 
@@ -198,6 +201,9 @@
 #define   SSP_1G			2
 #define  PM_IF_MODE_ENA			BIT(15)
 
+/* Port external MDIO Base address, use to access off-chip PHY */
+#define ENETC4_EMDIO_BASE		0x5c00
+
 /**********************ENETC Pseudo MAC port registers************************/
 /* Port pseudo MAC receive octets counter (64-bit) */
 #define ENETC4_PPMROCR			0x5080

drivers/net/ethernet/freescale/enetc/enetc_pf_common.c

@@ -176,7 +176,12 @@ static int enetc_mdio_probe(struct enetc_pf *pf, struct device_node *np)
 	bus->parent = dev;
 	mdio_priv = bus->priv;
 	mdio_priv->hw = &pf->si->hw;
-	mdio_priv->mdio_base = ENETC_EMDIO_BASE;
+
+	if (is_enetc_rev1(pf->si))
+		mdio_priv->mdio_base = ENETC_EMDIO_BASE;
+	else
+		mdio_priv->mdio_base = ENETC4_EMDIO_BASE;
+
 	snprintf(bus->id, MII_BUS_ID_SIZE, "%s", dev_name(dev));
 
 	err = of_mdiobus_register(bus, np);
@@ -221,7 +226,12 @@ static int enetc_imdio_create(struct enetc_pf *pf)
 	bus->phy_mask = ~0;
 	mdio_priv = bus->priv;
 	mdio_priv->hw = &pf->si->hw;
-	mdio_priv->mdio_base = ENETC_PM_IMDIO_BASE;
+
+	if (is_enetc_rev1(pf->si))
+		mdio_priv->mdio_base = ENETC_PM_IMDIO_BASE;
+	else
+		mdio_priv->mdio_base = ENETC4_PM_IMDIO_BASE;
+
 	snprintf(bus->id, MII_BUS_ID_SIZE, "%s-imdio", dev_name(dev));
 
 	err = mdiobus_register(bus);