Hi, > On Fri, Nov 27, 2015 at 02:39:10PM +0100, Lothar Waßmann wrote: > > When ENET_OUT is being used as reference clock for an external PHY, > > the clock must not be disabled while the PHY is active. Otherwise the > > PHY may lose its internal state and require a reset to become > > functional again. > > > > A symptom for this bug is a network interface that constantly toggles > > between UP and DOWN state: > > fec 800f0000.ethernet eth0: Link is Up - 100Mbps/Full - flow control rx/tx > > fec 800f0000.ethernet eth0: Link is Down > > fec 800f0000.ethernet eth0: Link is Up - 100Mbps/Full - flow control rx/tx > > fec 800f0000.ethernet eth0: Link is Down > > Hi Lothar > > When does this up/down happen? During normal operation when the link > is administrative up? > If booting with NFSROOT the rootfs cannot be mounted, because when the interface is brought up the PHY starts toggling the link state.
> When did this start happening? Did it happen before > 8fff755e9f8d net: fec: Ensure clocks are enabled while using mdio bus > No. The behaviour started exactly with this commit. Lothar Waßmann -- To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html