On Mon, Mar 19, 2018 at 3:47 PM, Dave Tucker <[email protected]> wrote:
> Ethernet on my Beaglebone Black is failing to come online about 3% of the
> time after power up.  Attached are dmesg output from times when ethernet
> works (good_dmesg.txt) and the more rare times when it fails
> (bad_dmesg.txt).  I've also attached full_bad_boot.txt which is the debug
> serial output from a boot that failed.  Here is a diff of the two dmesgs,
> which I think might highlight the relevant areas:
> 70c70
> < raid6: int32x1  xor()   140 MB/s
> ---
>> raid6: int32x1  xor()   143 MB/s
> 76c76
> < raid6: int32x8  xor()   118 MB/s
> ---
>> raid6: int32x8  xor()   117 MB/s
> 124c124
> < davinci_mdio 4a101000.mdio: detected phy mask fffffffe
> ---
>> davinci_mdio 4a101000.mdio: detected phy mask fffffffb
> 126c126
> < davinci_mdio 4a101000.mdio: phy[0]: device 4a101000.mdio:00, driver SMSC
> LAN8710/LAN8720
> ---
>> davinci_mdio 4a101000.mdio: phy[2]: device 4a101000.mdio:02, driver SMSC
>> LAN8710/LAN8720
> 169a170,172
>> EXT4-fs (mmcblk1p3): INFO: recovery required on readonly filesystem
>> EXT4-fs (mmcblk1p3): write access will be enabled during recovery
>> EXT4-fs (mmcblk1p3): recovery complete
> 174a178
>> EXT4-fs (mmcblk1p2): recovery complete
> 175a180
>> EXT4-fs (mmcblk1p4): recovery complete
> 183c188,189
> < SMSC LAN8710/LAN8720 4a101000.mdio:00: attached PHY driver [SMSC
> LAN8710/LAN8720] (mii_bus:phy_addr=4a101000.mdio:00, irq=-1)
> ---
>> libphy: PHY 4a101000.mdio:00 not found
>> net eth0: phy "4a101000.mdio:00" not found on slave 0, err -19
> 185,186c191
> < cpsw 4a100000.ethernet eth0: Link is Up - 100Mbps/Full - flow control
> rx/tx
> < IPv6: ADDRCONF(NETDEV_CHANGE): eth0: link becomes ready
> ---
>> random: crng init done
>
> I don't know what any of this means.  I do know I'm not doing anything
> different for the times that fail.  I've automated the entire process of
> turning it on and off and seeing if the network interface works.
>
> I'm running a custom build put together with Yocto (Rocko, 2.4), and I've
> compiled u-boot separately.  I can provide my device tree dts and uEnv.txt
> if needed.
>
> Is this a known problem?  What can I do to fix this?

Yes... Apply this patch, and it'll fix it 95% of the time...

https://github.com/RobertCNelson/bb-kernel/blob/am33x-v4.12/patches/drivers/ti/cpsw/0001-cpsw-search-for-phy.patch

Later boards (am43/etc) added a gpio to reset the phy, due to what was
seen on this design..

Regards,

-- 
Robert Nelson
https://rcn-ee.com/

-- 
For more options, visit http://beagleboard.org/discuss
--- 
You received this message because you are subscribed to the Google Groups 
"BeagleBoard" group.
To unsubscribe from this group and stop receiving emails from it, send an email 
to [email protected].
To view this discussion on the web visit 
https://groups.google.com/d/msgid/beagleboard/CAOCHtYg4fX7UZoWWgO1pDMTvF_O8%3Da5jQA%2BQEBa4fqD0h3aPqg%40mail.gmail.com.
For more options, visit https://groups.google.com/d/optout.

Reply via email to