> -----Original Message----- > From: Heiner Kallweit <hkallwe...@gmail.com> > Sent: 2021年4月8日 14:00 > To: Joakim Zhang <qiangqing.zh...@nxp.com>; Andrew Lunn > <and...@lunn.ch>; Russell King - ARM Linux <li...@armlinux.org.uk>; Jakub > Kicinski <k...@kernel.org>; David Miller <da...@davemloft.net>; Fugang > Duan <fugang.d...@nxp.com> > Cc: netdev@vger.kernel.org > Subject: Re: [PATCH net-next 2/3] net: fec: use mac-managed PHY PM > > On 08.04.2021 07:45, Joakim Zhang wrote: > > > >> -----Original Message----- > >> From: Heiner Kallweit <hkallwe...@gmail.com> > >> Sent: 2021年4月7日 23:53 > >> To: Andrew Lunn <and...@lunn.ch>; Russell King - ARM Linux > >> <li...@armlinux.org.uk>; Jakub Kicinski <k...@kernel.org>; David > >> Miller <da...@davemloft.net>; Fugang Duan <fugang.d...@nxp.com> > >> Cc: netdev@vger.kernel.org; Joakim Zhang <qiangqing.zh...@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.zh...@nxp.com> > >> Tested-by: Joakim Zhang <qiangqing.zh...@nxp.com> > >> Signed-off-by: Heiner Kallweit <hkallwe...@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. > > > The PHY PM resume callback (that used to call phy_init_hw) is a no-op now. > So we have to call it from the MAC resume callback. Power to the PHY may be > off during system suspend, therefore it may be reset to power-on defaults. > That's why phy_init_hw() should be called, that includes calling the PHY > drivers > config_init callback.
Yes, it is reasonable to invoke phy_init_hw() here to cover more cases. What I want to describe, we have not run into such case for FEC driver before. At least no one complain it before as I know. Anyway, re-initialize PHY here indeed can benefit more scenarios. Best Regards, Joakim Zhang > > Best Regards, > > Joakim Zhang > >> phy_start(ndev->phydev); > >> } > >> rtnl_unlock(); > >> -- > >> 2.31.1 > >> > >
