[U-Boot] [PATCH 5/7] net: mvpp2: allow MDIO registration for fixed links

[nhed+uboot at starry.com]

From: Igal Liberman <igall at marvell.com>

Currently, there are 2 valid cases for interface, PHY
and mdio relation:
  - If an interface has PHY handler, it'll call
    mdio_mii_bus_get_from_phy(), which will register
    MDIO bus.
  - If we want to use fixed-link for an interface,
    PHY handle is not defined in the DTS, and no
    MDIO is registered.

There is a third case, for some boards (with switch),
the MDIO is used for switch configuration, but the interface
itself uses fixed link. This patch allows this option by
checking if fixed-link subnode is defined, in this case,
MDIO bus is registers, but the PHY address is set to
PHY_MAX_ADDR for this interface, so this interface will
not try to access the PHY later on.

In addition, remove unnecessary check after
calling fdtdec_get_int().

This squahses a subsequent fix by same author

Signed-off-by: Igal Liberman <igall at marvell.com>
Reviewed-by: Kostya Porotchkin <kostap at marvell.com>
Reviewed-by: Stefan Chulski <stefanc at marvell.com>
Signed-off-by: Nevo Hed <nhed+github at starry.com>
---

 drivers/net/mvpp2.c | 16 +++++++++-------
 1 file changed, 9 insertions(+), 7 deletions(-)

diff --git a/drivers/net/mvpp2.c b/drivers/net/mvpp2.c
index 5f908113f2..da550450eb 100644
--- a/drivers/net/mvpp2.c
+++ b/drivers/net/mvpp2.c
@@ -4707,6 +4707,7 @@ static int phy_info_parse(struct udevice *dev, struct mvpp2_port *port)
 	u32 phyaddr = 0;
 	int phy_mode = -1;
 	int ret;
+	int fixed_link = 0;
 
 	/* Default mdio_base from the same eth base */
 	if (port->priv->hw_version == MVPP21)
@@ -4715,16 +4716,17 @@ static int phy_info_parse(struct udevice *dev, struct mvpp2_port *port)
 		port->mdio_base = port->priv->iface_base + MVPP22_SMI;
 
 	phy_node = fdtdec_lookup_phandle(gd->fdt_blob, port_node, "phy");
+	fixed_link = fdt_subnode_offset(gd->fdt_blob, port_node, "fixed-link");
 
 	if (phy_node > 0) {
-		ofnode phy_ofnode;
-		fdt_addr_t phy_base;
-
-		phyaddr = fdtdec_get_int(gd->fdt_blob, phy_node, "reg", 0);
-		if (phyaddr < 0) {
-			dev_err(&pdev->dev, "could not find phy address\n");
-			return -1;
+		if (fixed_link != -FDT_ERR_NOTFOUND) {
+			/* phy_addr is set to invalid value for fixed links */
+			phyaddr = PHY_MAX_ADDR;
+		} else {
+			phyaddr = fdtdec_get_int(gd->fdt_blob, phy_node,
+						 "reg", 0);
 		}
+
 		ret = mdio_mii_bus_get_from_phy(phy_node, &port->bus);
 		if (ret)
 			return ret;
-- 
2.21.0