On Tue, Oct 11, 2016 at 09:32:30AM -0500, Jeremy Linton wrote: > On 10/10/2016 12:41 PM, Kyle Roeschley wrote: > > Because the SMSC PHY completes auto-negotiation before the driver is > > ready to handle interrupts, the PHY state machine never realizes that we > > have a link. Clear the ANENABLE bit on initialization, which lets > > genphy_config_aneg do its thing when that code is hit later. > > > > While this patch does fix the problem we see (no link on boot without > > re-plugging the cable), it seems like the generic PHY code should be > > able to handle auto-negotiation completing before interrupts are > > enabled. Submitted as an RFC in the hopes that someone has an idea as to > > how that could be done. > > Hi, > > Which smsc chip/driver? Maybe assuring the device interrupts are enabled > before the phy is started is a solution? > > The whole problem sounds similar to what was recently happening in the > smsc911x driver, but AFAIK that driver is basically only polling at this > point so connecting the phy before the interrupts are enabled shouldn't be a > problem. >
We're using the SMSC LAN8720A with the Cadence MACB ethernet controller. Interrupts are enabled before the phy is started, but it looks like the patch Florian pointed me to (https://www.spinics.net/lists/netdev/msg397857.html) fixes my interrupt problem. > > > > This fix is copied from commit 99f81afc139c ("phy: micrel: Disable auto > > negotiation on startup"). > > > > Signed-off-by: Kyle Roeschley <kyle.roesch...@ni.com> > > --- > > drivers/net/phy/smsc.c | 10 ++++++++++ > > 1 file changed, 10 insertions(+) > > > > diff --git a/drivers/net/phy/smsc.c b/drivers/net/phy/smsc.c > > index b62c4aa..8de8011 100644 > > --- a/drivers/net/phy/smsc.c > > +++ b/drivers/net/phy/smsc.c > > @@ -62,6 +62,16 @@ static int smsc_phy_config_init(struct phy_device > > *phydev) > > return rc; > > } > > > > + if (phy_interrupt_is_valid(phydev)) { > > + rc = phy_read(phydev, MII_BMCR); > > + if (rc < 0) > > + return rc; > > + > > + rc = phy_write(phydev, MII_BMCR, rc & ~BMCR_ANENABLE); > > + if (rc < 0) > > + return rc; > > + } > > + > > return smsc_phy_ack_interrupt(phydev); > > } > > > > > -- Kyle Roeschley Software Engineer National Instruments
