RE: [PATCH net-next 2/3] net: fec: use mac-managed PHY PM

[Joakim Zhang <qiangqing.zhang@nxp.com>]

> -----Original Message-----
> From: Heiner Kallweit <hkallweit1@gmail.com>
> Sent: 2021年4月7日 23:53
> To: Andrew Lunn <andrew@lunn.ch>; Russell King - ARM Linux
> <linux@armlinux.org.uk>; Jakub Kicinski <kuba@kernel.org>; David Miller
> <davem@davemloft.net>; Fugang Duan <fugang.duan@nxp.com>
> Cc: netdev@vger.kernel.org; Joakim Zhang <qiangqing.zhang@nxp.com>
> Subject: [PATCH net-next 2/3] net: fec: use mac-managed PHY PM
> 
> Use the new mac_managed_pm flag to work around an issue with KSZ8081
> PHY that becomes unstable when a soft reset is triggered during aneg.
> 
> Reported-by: Joakim Zhang <qiangqing.zhang@nxp.com>
> Tested-by: Joakim Zhang <qiangqing.zhang@nxp.com>
> Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
> ---
>  drivers/net/ethernet/freescale/fec_main.c | 3 +++
>  1 file changed, 3 insertions(+)
> 
> diff --git a/drivers/net/ethernet/freescale/fec_main.c
> b/drivers/net/ethernet/freescale/fec_main.c
> index 3db882322..70aea9c27 100644
> --- a/drivers/net/ethernet/freescale/fec_main.c
> +++ b/drivers/net/ethernet/freescale/fec_main.c
> @@ -2048,6 +2048,8 @@ static int fec_enet_mii_probe(struct net_device
> *ndev)
>  	fep->link = 0;
>  	fep->full_duplex = 0;
> 
> +	phy_dev->mac_managed_pm = 1;
> +
>  	phy_attached_info(phy_dev);
> 
>  	return 0;
> @@ -3864,6 +3866,7 @@ static int __maybe_unused fec_resume(struct
> device *dev)
>  		netif_device_attach(ndev);
>  		netif_tx_unlock_bh(ndev);
>  		napi_enable(&fep->napi);
> +		phy_init_hw(ndev->phydev);


For now, I think we doesn't need to re-initialize PHY after MAC resume back, it also can be done by PHY driver if it needed.

Best Regards,
Joakim Zhang
>  		phy_start(ndev->phydev);
>  	}
>  	rtnl_unlock();
> --
> 2.31.1
>