Hey Everyone,
I have been testing the beaglebone black for some time now, and I have noticed that the Ethernet tends to die after prolonged operation (1 day +).
Beaglebone is run off of a good quality 5V DC supply, with constant traffic being streamed on it. CPU usage is around 40%.
Below is the output of dmesg:
[ 9.145976] net eth0: initializing cpsw version 1.12 (0)
[ 9.150610] net eth0: phy found : id is : 0x7c0f1
[ 9.150644] libphy: PHY 4a101000.mdio:01 not found
[ 9.155748] net eth0: phy 4a101000.mdio:01 not found on slave 1
[ 12.227778] libphy: 4a101000.mdio:00 - Link is Up - 100/Full
[102008.098372] libphy: 4a101000.mdio:00 - Link is Down
Link suddenly dies after many hours of being up. Beaglebone is connected to an ethernet switch and was left completely alone at that time (no tinkering).
Upon attempting to revive the ethernet link without reboot, “ip link set eth0 down” seems to succeed, however “ip link set eth0 up” fails with:
root@beaglebone:~# ip link set eth0 up
[170649.910190] net eth0: phy 4a101000.mdio:00 not found on slave 0
[170649.916577] libphy: PHY 4a101000.mdio:01 not found
[170649.921721] net eth0: phy 4a101000.mdio:01 not found on slave 1
Observations: after the ethernet dies, the orange light on the ethernet plug goes out, and the left LED blinks sporadically green.
Unplugging the ethernet makes the left LED go solid green, right LED still off.
Interestingly, the ethernet switch shows 1Gbps negotiation. Obviously link is not functional (but switch light is ON).
Connecting the bone in this state to a 10/100 switch causes both LEDs on the bone to go completely off, while the 10/100 switch shows 10mbps negotiation.
Rebooting the bone has no effect on ethernet (still dead):
[ 5.705411] net eth0: initializing cpsw version 1.12 (0)
[ 5.707104] libphy: PHY 4a101000.mdio:00 not found
[ 5.712133] net eth0: phy 4a101000.mdio:00 not found on slave 0
[ 5.718328] libphy: PHY 4a101000.mdio:01 not found
[ 5.723339] net eth0: phy 4a101000.mdio:01 not found on slave 1
Only a power cycle or pressing RESET on the board fixes this:
[ 8.242920] net eth0: initializing cpsw version 1.12 (0)
[ 8.256913] net eth0: phy found : id is : 0x7c0f1
[ 8.256950] libphy: PHY 4a101000.mdio:01 not found
[ 8.262017] net eth0: phy 4a101000.mdio:01 not found on slave 1
[ 11.333235] libphy: 4a101000.mdio:00 - Link is Up - 100/Full
Could this be the RESET line of the PHY picking up some glitch? I havn’t checked the schematics/layout but I hope it turns out to be a cap being needed on the PHY reset line. Otherwise, I can’t thing of something else.
Gerald: Help?
Regards
Hussein