net: axienet: Set mac_managed_pm

The external PHY will undergo a soft reset twice during the resume process
when it wake up from suspend. The first reset occurs when the axienet
driver calls phylink_of_phy_connect(), and the second occurs when
mdio_bus_phy_resume() invokes phy_init_hw(). The second soft reset of the
external PHY does not reinitialize the internal PHY, which causes issues
with the internal PHY, resulting in the PHY link being down. To prevent
this, setting the mac_managed_pm flag skips the mdio_bus_phy_resume()
function.

Fixes: a129b41 ("Revert "net: phy: dp83867: perform soft reset and retain established link"")
Signed-off-by: Nick Hu <[email protected]>
Reviewed-by: Jacob Keller <[email protected]>
Link: https://patch.msgid.link/[email protected]
Signed-off-by: Paolo Abeni <[email protected]>

drivers/net/ethernet/xilinx/xilinx_axienet_main.c

@@ -2897,6 +2897,7 @@ static int axienet_probe(struct platform_device *pdev)
 
 	lp->phylink_config.dev = &ndev->dev;
 	lp->phylink_config.type = PHYLINK_NETDEV;
+	lp->phylink_config.mac_managed_pm = true;
 	lp->phylink_config.mac_capabilities = MAC_SYM_PAUSE | MAC_ASYM_PAUSE |
 		MAC_10FD | MAC_100FD | MAC_1000FD;