The PHY on board is the SMSC LAN8720 With the generic PHY driver selected: http://pastebin.com/A4MH4Ptw
[ 28.828761] fec 800f0000.ethernet eth0: Freescale FEC PHY driver [Generic PHY] (mii_bus:phy_addr=800f0000.etherne:00, irq=-1) [ 28.840626] IPv6: ADDRCONF(NETDEV_UP): eth0: link is not ready [ 30.827536] libphy: 800f0000.etherne:00 - Link is Up - 100/Full [ 30.833739] IPv6: ADDRCONF(NETDEV_CHANGE): eth0: link becomes ready [ 32.986999] IPv6: ADDRCONF(NETDEV_UP): usb0: link is not ready [ 37.316421] fec 800f0000.ethernet eth0: Freescale FEC PHY driver [Generic PHY] (mii_bus:phy_addr=800f0000.etherne:00, irq=-1) [ 38.345047] fec 800f0000.ethernet eth0: MDIO read timeout [ 39.506210] IPv6: ADDRCONF(NETDEV_UP): eth0: link is not ready [ 40.374961] fec 800f0000.ethernet eth0: MDIO read timeout With the SMSC PHY driver selected: http://pastebin.com/DhdDyrMv [ 28.778974] fec 800f0000.ethernet eth0: Freescale FEC PHY driver [SMSC LAN8710/LAN8720] (mii_bus:phy_addr=800f0000.etherne:00, irq=-1) [ 28.791742] IPv6: ADDRCONF(NETDEV_UP): eth0: link is not ready [ 30.773078] libphy: 800f0000.etherne:00 - Link is Up - 100/Full [ 30.779286] IPv6: ADDRCONF(NETDEV_CHANGE): eth0: link becomes ready [ 32.934692] IPv6: ADDRCONF(NETDEV_UP): usb0: link is not ready [ 37.242162] fec 800f0000.ethernet eth0: Freescale FEC PHY driver [SMSC LAN8710/LAN8720] (mii_bus:phy_addr=800f0000.etherne:00, irq=-1) [ 38.270611] fec 800f0000.ethernet eth0: MDIO read timeout [ 39.415256] IPv6: ADDRCONF(NETDEV_UP): eth0: link is not ready [ 40.300454] fec 800f0000.ethernet eth0: MDIO read timeout On Tue, May 6, 2014 at 12:24 PM, Florian Fainelli <f.faine...@gmail.com> wrote: > 2014-05-06 12:12 GMT-07:00 Brian Lilly <br...@crystalfontz.com>: >> It is happening during boot up: >> >> <snip, kernel 3.12 > >> >> Configuring network interfaces... [ 35.117114] fec 800f0000.ethernet >> eth0: Freescale FEC PHY driver [SMSC LAN8710/LAN8720] > > Note that the SMSC PHY driver is picked up here, and that specific > driver implements a different phy_read_status() callback due to how > the PHY operates. The PHY driver also overrides the config_init() > callback to perform some PHY-specific initialization. See below for > more. > >> (mii_bus:phy_addr=800f0000.etherne:00, irq=-1) >> [ 35.129967] IPv6: ADDRCONF(NETDEV_UP): eth0: link is not ready >> udhcpc (v1.21.1) started >> >> Sending discover... >> >> [ 37.113901] libphy: 800f0000.etherne:00 - Link is Up - 100/Full >> [ 37.120134] IPv6: ADDRCONF(NETDEV_CHANGE): eth0: link becomes ready >> Sending discover... >> >> Sending select for 10.10.10.217... >> Lease of 10.10.10.217 obtained, lease time 86400 >> /etc/udhcpc.d/50default: Adding DNS 10.10.10.13 >> [ 39.319957] IPv6: ADDRCONF(NETDEV_UP): usb0: link is not ready >> done. >> Starting rpcbind daemon...done. >> net.ipv4.conf.default.rp_filter = 1 >> net.ipv4.conf.all.rp_filter = 1 >> Mon Apr 14 22:40:00 UTC 2014 >> INIT: Entering runlevel: 5 >> Starting Xserver >> Starting system message bus: dbus. >> Starting Connection Manager >> Starting wpa_supplicant >> Successfully initialized wpa_supplicant >> Starting Dropbear SSH server >> [ 44.754915] fec 800f0000.ethernet eth0: Freescale FEC PHY driver >> [SMSC LAN8710/LAN8720] (mii_bus:phy_addr=800f0000.etherne:00, irq=-1) > > The correct PHY driver is selected here... > >> [ 45.781364] fec 800f0000.ethernet eth0: MDIO read timeout >> [ 46.826170] IPv6: ADDRCONF(NETDEV_UP): eth0: link is not ready >> [ 47.811385] fec 800f0000.ethernet eth0: MDIO read timeout > > But we are still seeing MDIO read timeouts, which is not great. > >> >> With a different kernel (3.14): >> >> [ 28.989897] fec 800f0000.ethernet eth0: Freescale FEC PHY driver >> [Generic PHY] (mii_bus:phy_addr=800f0000.etherne:00, irq=-1) >> [ 30.991210] libphy: 800f0000.etherne:00 - Link is Up - 100/Full >> [ 37.369372] fec 800f0000.ethernet eth0: Freescale FEC PHY driver >> [Generic PHY] (mii_bus:phy_addr=800f0000.etherne:00, irq=-1) > > Here, the Generic PHY driver has been selected, which will use the > MII_BMSR register contents to determine the Link status and > parameters. You might want to make sure that your board selects the > appropriate PHY driver, such that we are not chasing two issues here. > >> [ 38.398346] fec 800f0000.ethernet eth0: MDIO read timeout >> [ 39.438412] fec 800f0000.ethernet eth0: MDIO read timeout >> [ 39.468419] fec 800f0000.ethernet eth0: MDIO write timeout >> [ 40.498848] fec 800f0000.ethernet eth0: MDIO read timeout > > It would also be helpful to print the register that were accessed, > such that you could correlate this with the exact steps in the PHY > library state machine. Please also retry the experiment with the SMSC > PHY driver enabled, as it does some PHY specific initialization that > seems to be relevant. Then we are hopefully left with only the MDIO > timeout issue and not the PHY mis-configuration + MDIO timeout. > >> >> Afterward I have to ifdown eth0, ifup eth0 and then it functions >> normally, without reverting the commit. >> >> root@cfa100xx:~# ifdown eth0 >> [ 1154.679658] fec 800f0000.ethernet eth0: Freescale FEC PHY driver >> [Generic PHY] (mii_bus:phy_addr=800f0000.etherne:00, irq=-1) >> root@cfa100xx:~# ifup eth0 >> udhcpc (v1.21.1) started >> Sending discover... >> [ 1156.679547] libphy: 800f0000.etherne:00 - Link is Up - 100/Full >> Sending discover... >> Sending select for 10.10.10.217... >> Lease of 10.10.10.217 obtained, lease time 86400 >> ip: RTNETLINK answers: File exists >> >> -- >> Brian >> >> >> On Tue, May 6, 2014 at 11:11 AM, Uwe Kleine-König >> <u.kleine-koe...@pengutronix.de> wrote: >>> Hello Brian, >>> >>> On Tue, May 06, 2014 at 09:44:34AM -0700, Brian Lilly wrote: >>>> With commit a264b981f2c76e281ef27e7232774bf6c54ec865 we're having eth0 >>>> come up, then brought right back down with an MDIO rx timeout moments >>>> after. Adding back in the removed code keeps the interface alive and >>>> it's working afterward without trouble. I've tested the re-inserted >>>> code in 3.12, 3.14 without issue on our boards. >>> So you can reliably trigger that problem? You're just doing >>> >>> ifconfig eth0 1.2.3.4 up >>> >>> (or equivalent) and the interface goes down without further >>> interference with the above mentioned commit? The exact error you're >>> seeing is >>> >>> MDIO read timeout >>> >>> (with some prefix saying something about fec and eth0 I think)? >>> >>> This error is also present with a264b981f2 reverted, just doesn't affect >>> eth0 being functional? Does the timeout always happen, or only on >>> specific addresses? >>> >>> This is not a proper fix, but does it help to increment FEC_MII_TIMEOUT? >>> >>>> Is there something else that can be done to prevent the MDIO timeouts? >>>> We are using basically the same schematic for networking as the >>>> imx28evk. >>> Hard to say, but assuming it works just fine on the imx28evk for you, >>> too, there seems to be some hardware difference that makes your machine >>> fail. (That doesn't mean it's not fixable in software.) >>> >>> I don't know if a mdio read error is intended to make the device go >>> down, maybe one the the netdev guys can answer that. >>> Assuming that it's not intended, instrument the code, find out how that >>> timeout makes your device go down and find the wrong branch. I'd start >>> with adding stackdumps when the mdio timeout happens and when >>> fec_enet_start_xmit is called with fep->link == 0. >>> >>> Best regards >>> Uwe >>> >>> -- >>> Pengutronix e.K. | Uwe Kleine-König | >>> Industrial Linux Solutions | http://www.pengutronix.de/ | >> -- >> 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 > > > > -- > Florian -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/