net: mvpp2x: fix phy connected to wrong mdio issue

A8K marvell SoC has two South Bridge communication controllers(CP0 and CP1).
Each communication controller has packet processor ports and MDIO.
On MACHIATOBin board ports from CP1 are connected to mdio on CP0.

Issue:
Wrong base address is assigned to MDIO interface during probe.

Fix:
Get MDIO address from PHY handler parent base address.

This should be refined in the future when MDIO driver is implemented.

Signed-off-by: Stefan Chulski <stefanc@marvell.com>
Tested-by: iSoC Platform CI <ykjenk@marvell.com>
Reviewed-by: Igal Liberman <igall@marvell.com>
Acked-by: Joe Hershberger <joe.hershberger@ni.com>
Signed-off-by: Stefan Roese <sr@denx.de>

drivers/net/mvpp2.c

@@ -31,6 +31,7 @@
 #include <linux/compat.h>
 #include <linux/mbus.h>
 #include <asm-generic/gpio.h>
+#include <fdt_support.h>
 
 DECLARE_GLOBAL_DATA_PTR;
 
@@ -4739,10 +4740,11 @@ static int phy_info_parse(struct udevice *dev, struct mvpp2_port *port)
 {
 	int port_node = dev_of_offset(dev);
 	const char *phy_mode_str;
-	int phy_node;
+	int phy_node, mdio_off, cp_node;
 	u32 id;
 	u32 phyaddr = 0;
 	int phy_mode = -1;
+	u64 mdio_addr;
 
 	phy_node = fdtdec_lookup_phandle(gd->fdt_blob, port_node, "phy");
 
@@ -4752,6 +4754,28 @@ static int phy_info_parse(struct udevice *dev, struct mvpp2_port *port)
 			dev_err(&pdev->dev, "could not find phy address\n");
 			return -1;
 		}
+		mdio_off = fdt_parent_offset(gd->fdt_blob, phy_node);
+
+		/* TODO: This WA for mdio issue. U-boot 2017 don't have
+		 * mdio driver and on MACHIATOBin board ports from CP1
+		 * connected to mdio on CP0.
+		 * WA is to get mdio address from phy handler parent
+		 * base address. WA should be removed after
+		 * mdio driver implementation.
+		 */
+		mdio_addr = fdtdec_get_uint(gd->fdt_blob,
+					    mdio_off, "reg", 0);
+
+		cp_node = fdt_parent_offset(gd->fdt_blob, mdio_off);
+		mdio_addr |= fdt_get_base_address((void *)gd->fdt_blob,
+						  cp_node);
+
+		port->priv->mdio_base = (void *)mdio_addr;
+
+		if (port->priv->mdio_base < 0) {
+			dev_err(&pdev->dev, "could not find mdio base address\n");
+			return -1;
+		}
 	} else {
 		phy_node = 0;
 	}