[PATCH 4.19 270/313] Revert "net: phy: marvell: avoid pause mode on SGMII-to-Copper for 88e151x"

[Greg Kroah-Hartman]

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

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

From: Russell King <rmk+kernel@xxxxxxxxxxxxxxx>

[ Upstream commit c14f07c6211cc01d52ed92cce1fade5071b8d197 ]

This reverts commit 6623c0fba10ef45b64ca213ad5dec926f37fa9a0.

The original diagnosis was incorrect: it appears that the NIC had
PHY polling mode enabled, which meant that it overwrote the PHYs
advertisement register during negotiation.

Signed-off-by: Russell King <rmk+kernel@xxxxxxxxxxxxxxx>
Tested-by: Yonglong Liu <liuyonglong@xxxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
 drivers/net/phy/marvell.c |   12 ------------
 1 file changed, 12 deletions(-)

--- a/drivers/net/phy/marvell.c
+++ b/drivers/net/phy/marvell.c
@@ -868,8 +868,6 @@ static int m88e1510_config_init(struct p
 
 	/* SGMII-to-Copper mode initialization */
 	if (phydev->interface == PHY_INTERFACE_MODE_SGMII) {
-		u32 pause;
-
 		/* Select page 18 */
 		err = marvell_set_page(phydev, 18);
 		if (err < 0)
@@ -892,16 +890,6 @@ static int m88e1510_config_init(struct p
 		err = marvell_set_page(phydev, MII_MARVELL_COPPER_PAGE);
 		if (err < 0)
 			return err;
-
-		/* There appears to be a bug in the 88e1512 when used in
-		 * SGMII to copper mode, where the AN advertisement register
-		 * clears the pause bits each time a negotiation occurs.
-		 * This means we can never be truely sure what was advertised,
-		 * so disable Pause support.
-		 */
-		pause = SUPPORTED_Pause | SUPPORTED_Asym_Pause;
-		phydev->supported &= ~pause;
-		phydev->advertising &= ~pause;
 	}
 
 	return m88e1318_config_init(phydev);