From 1e354cb3931472c6e88aa6c46d4bda9beddfdcc4 Mon Sep 17 00:00:00 2001
From: Alex Marginean <alexandru.marginean@nxp.com>
Date: Mon, 25 Nov 2019 17:57:27 +0200
Subject: [PATCH] drivers: net: fsl_enetc: register internal MDIO bus

This bus is used to access internal SoC PHYs.  These PHYs are configured
by the ENETC driver directly, but it's useful to have command line access
to this MDIO to debug the system especially when using new external PHYs.

Signed-off-by: Alex Marginean <alexandru.marginean@nxp.com>
Acked-by: Joe Hershberger <joe.hershberger@ni.com>
---
 drivers/net/fsl_enetc.c | 15 +++++++--------
 1 file changed, 7 insertions(+), 8 deletions(-)

diff --git a/drivers/net/fsl_enetc.c b/drivers/net/fsl_enetc.c
index e86f3dddb5..02c1ee70d9 100644
--- a/drivers/net/fsl_enetc.c
+++ b/drivers/net/fsl_enetc.c
@@ -156,19 +156,14 @@ static void enetc_start_pcs(struct udevice *dev)
 
 	priv->if_type = PHY_INTERFACE_MODE_NONE;
 
-	/* check internal mdio capability, not all ports need it */
+	/* register internal MDIO for debug purposes */
 	if (enetc_read_port(priv, ENETC_PCAPR0) & ENETC_PCAPRO_MDIO) {
-		/*
-		 * set up internal MDIO, this is part of ETH PCI function and is
-		 * used to access serdes / internal SoC PHYs.
-		 * We don't currently register it as a MDIO bus as it goes away
-		 * when the interface is removed, so it can't practically be
-		 * used in the console.
-		 */
 		priv->imdio.read = enetc_mdio_read;
 		priv->imdio.write = enetc_mdio_write;
 		priv->imdio.priv = priv->port_regs + ENETC_PM_IMDIO_BASE;
 		strncpy(priv->imdio.name, dev->name, MDIO_NAME_LEN);
+		if (!miiphy_get_dev_by_name(priv->imdio.name))
+			mdio_register(&priv->imdio);
 	}
 
 	if (!ofnode_valid(dev->node)) {
@@ -451,6 +446,10 @@ static void enetc_stop(struct udevice *dev)
 {
 	/* FLR is sufficient to quiesce the device */
 	dm_pci_flr(dev);
+	/* leave the BARs accessible after we stop, this is needed to use
+	 * internal MDIO in command line.
+	 */
+	dm_pci_clrset_config16(dev, PCI_COMMAND, 0, PCI_COMMAND_MEMORY);
 }
 
 /*
-- 
2.39.5