[U-Boot] [PATCH v4 2/5] net: mvpp2: mark phy as invalid in case of missing appropriate driver

[nhed+uboot at starry.com]

From: Grzegorz Jaszczyk <jaz at semihalf.com>

If the phy doesn't match with any existing u-boot drivers, the phy
framework will connect it to the generic one which uid ==
0xffffffff. In this case, act as if the phy wouldn't be declared in
dts. Otherwise, in case of 3310 (for which the driver doesn't exist)
the link is marked as always down. Removing phy entry from dts in case
of 3310 is not a good option because it is required for the
phy_fw_down procedure.

This patch fixes the issue with the link always down on MCBIN board.

nhed: added NULL deref test.

Signed-off-by: Grzegorz Jaszczyk <jaz at semihalf.com>
Reviewed-by: Igal Liberman <igall at marvell.com>
Tested-by: Igal Liberman <igall at marvell.com>
Signed-off-by: Nevo Hed <nhed+github at starry.com>
---
 drivers/net/mvpp2.c | 23 +++++++++++++++++++++++
 1 file changed, 23 insertions(+)

diff --git a/drivers/net/mvpp2.c b/drivers/net/mvpp2.c
index f36c8236b1..4ba6f9be3e 100644
--- a/drivers/net/mvpp2.c
+++ b/drivers/net/mvpp2.c
@@ -4501,6 +4501,29 @@ static void mvpp2_phy_connect(struct udevice *dev, struct mvpp2_port *port)
 	if (!port->init || port->link == 0) {
 		phy_dev = phy_connect(port->bus, port->phyaddr, dev,
 				      port->phy_interface);
+
+		/*
+		 * If the phy doesn't match with any existing u-boot drivers the
+		 * phy framework will connect it to generic one which
+		 * uid == 0xffffffff. In this case act as if the phy wouldn't be
+		 * declared in dts. Otherwise in case of 3310 (for which the
+		 * driver doesn't exist) the link will not be correctly
+		 * detected. Removing phy entry from dts in case of 3310 is not
+		 * an option because it is required for the phy_fw_down
+		 * procedure.
+		 */
+		if (phy_dev &&
+		    phy_dev->drv->uid == 0xffffffff) {/* Generic phy */
+			netdev_warn(port->dev,
+				    "Marking phy as invalid, link will not be checked\n");
+			/* set phy_addr to invalid value */
+			port->phyaddr = PHY_MAX_ADDR;
+			mvpp2_egress_enable(port);
+			mvpp2_ingress_enable(port);
+
+			return;
+		}
+
 		port->phy_dev = phy_dev;
 		if (!phy_dev) {
 			netdev_err(port->dev, "cannot connect to phy\n");
-- 
2.21.0