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From:   Clemens Gruber <clemens.gruber@pqgruber.com>
To:     netdev@vger.kernel.org
Cc:     Russell King <linux@armlinux.org.uk>, Andrew Lunn <andrew@lunn.ch>,
        Florian Fainelli <f.fainelli@gmail.com>,
        Heiner Kallweit <hkallweit1@gmail.com>,
        "David S . Miller" <davem@davemloft.net>,
        Jakub Kicinski <kuba@kernel.org>, linux-kernel@vger.kernel.org,
        Clemens Gruber <clemens.gruber@pqgruber.com>
Subject: [PATCH v2] net: phy: marvell: Fix pause frame negotiation
Date:   Sat, 11 Apr 2020 18:51:25 +0200
Message-Id: <20200411165125.1091-1-clemens.gruber@pqgruber.com>
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The negotiation of flow control / pause frame modes was broken since
commit fcf1f59afc67 ("net: phy: marvell: rearrange to use
genphy_read_lpa()") moved the setting of phydev->duplex below the
phy_resolve_aneg_pause call. Due to a check of DUPLEX_FULL in that
function, phydev->pause was no longer set.

Fix it by moving the parsing of the status variable before the blocks
dealing with the pause frames.

As the Marvell 88E1510 datasheet does not specify the timing between the
link status and the "Speed and Duplex Resolved" bit, we have to force
the link down as long as the resolved bit is not set, to avoid reporting
link up before we even have valid Speed/Duplex.

Tested with a Marvell 88E1510 (RGMII to Copper/1000Base-T)

Fixes: fcf1f59afc67 ("net: phy: marvell: rearrange to use genphy_read_lpa()")
Signed-off-by: Clemens Gruber <clemens.gruber@pqgruber.com>
---
Changes since v1:
- Force link to 0 if resolved bit is not set as suggested by Russell King

 drivers/net/phy/marvell.c | 46 ++++++++++++++++++++-------------------
 1 file changed, 24 insertions(+), 22 deletions(-)

diff --git a/drivers/net/phy/marvell.c b/drivers/net/phy/marvell.c
index 9a8badafea8a..561df5e33f65 100644
--- a/drivers/net/phy/marvell.c
+++ b/drivers/net/phy/marvell.c
@@ -1278,6 +1278,30 @@ static int marvell_read_status_page_an(struct phy_device *phydev,
 	int lpa;
 	int err;
 
+	if (!(status & MII_M1011_PHY_STATUS_RESOLVED)) {
+		phydev->link = 0;
+		return 0;
+	}
+
+	if (status & MII_M1011_PHY_STATUS_FULLDUPLEX)
+		phydev->duplex = DUPLEX_FULL;
+	else
+		phydev->duplex = DUPLEX_HALF;
+
+	switch (status & MII_M1011_PHY_STATUS_SPD_MASK) {
+	case MII_M1011_PHY_STATUS_1000:
+		phydev->speed = SPEED_1000;
+		break;
+
+	case MII_M1011_PHY_STATUS_100:
+		phydev->speed = SPEED_100;
+		break;
+
+	default:
+		phydev->speed = SPEED_10;
+		break;
+	}
+
 	if (!fiber) {
 		err = genphy_read_lpa(phydev);
 		if (err < 0)
@@ -1306,28 +1330,6 @@ static int marvell_read_status_page_an(struct phy_device *phydev,
 		}
 	}
 
-	if (!(status & MII_M1011_PHY_STATUS_RESOLVED))
-		return 0;
-
-	if (status & MII_M1011_PHY_STATUS_FULLDUPLEX)
-		phydev->duplex = DUPLEX_FULL;
-	else
-		phydev->duplex = DUPLEX_HALF;
-
-	switch (status & MII_M1011_PHY_STATUS_SPD_MASK) {
-	case MII_M1011_PHY_STATUS_1000:
-		phydev->speed = SPEED_1000;
-		break;
-
-	case MII_M1011_PHY_STATUS_100:
-		phydev->speed = SPEED_100;
-		break;
-
-	default:
-		phydev->speed = SPEED_10;
-		break;
-	}
-
 	return 0;
 }
 
-- 
2.26.0