[PATCH 4.20 22/76] net: mscc: Enable all ports in QSGMII

[Greg Kroah-Hartman]

4.20-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Kavya Sree Kotagiri <kavyasree.kotagiri@xxxxxxxxxxxxx>

[ Upstream commit 084e5bb16bd7dc2b551bbd9fb358bf73e03ee8d8 ]

When Ocelot phy-mode is QSGMII, all 4 ports involved in
QSGMII shall be kept out of reset and
Tx lanes shall be enabled to pass the data.

Fixes: a556c76adc05 ("net: mscc: Add initial Ocelot switch support")
Signed-off-by: Kavya Sree Kotagiri <kavyasree.kotagiri@xxxxxxxxxxxxx>
Signed-off-by: Steen Hegelund <Steen.Hegelund@xxxxxxxxxxxxx>
Co-developed-by: Steen Hegelund <Steen.Hegelund@xxxxxxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
 drivers/net/ethernet/mscc/ocelot_board.c |   14 +++++++++++---
 1 file changed, 11 insertions(+), 3 deletions(-)

--- a/drivers/net/ethernet/mscc/ocelot_board.c
+++ b/drivers/net/ethernet/mscc/ocelot_board.c
@@ -266,6 +266,7 @@ static int mscc_ocelot_probe(struct plat
 		struct phy *serdes;
 		void __iomem *regs;
 		char res_name[8];
+		int phy_mode;
 		u32 port;
 
 		if (of_property_read_u32(portnp, "reg", &port))
@@ -291,11 +292,11 @@ static int mscc_ocelot_probe(struct plat
 		if (err)
 			return err;
 
-		err = of_get_phy_mode(portnp);
-		if (err < 0)
+		phy_mode = of_get_phy_mode(portnp);
+		if (phy_mode < 0)
 			ocelot->ports[port]->phy_mode = PHY_INTERFACE_MODE_NA;
 		else
-			ocelot->ports[port]->phy_mode = err;
+			ocelot->ports[port]->phy_mode = phy_mode;
 
 		switch (ocelot->ports[port]->phy_mode) {
 		case PHY_INTERFACE_MODE_NA:
@@ -303,6 +304,13 @@ static int mscc_ocelot_probe(struct plat
 		case PHY_INTERFACE_MODE_SGMII:
 			break;
 		case PHY_INTERFACE_MODE_QSGMII:
+			/* Ensure clock signals and speed is set on all
+			 * QSGMII links
+			 */
+			ocelot_port_writel(ocelot->ports[port],
+					   DEV_CLOCK_CFG_LINK_SPEED
+					   (OCELOT_SPEED_1000),
+					   DEV_CLOCK_CFG);
 			break;
 		default:
 			dev_err(ocelot->dev,