[U-Boot] Fw: TFTP fails when using network switch

Jerry Van Baren
2009-01-07T12:52:58Z

Wolfgang Denk wrote:
> Dear Ulf Samuelsson,
>
> In message <1231282371.32308.276.camel@elrond.atmel.com> you wrote:
>> It was tracked down to the autoconfiguration of the
>> Ethernet PHY, so one of the PHYs ended up in
>> 100 Mbps Half Duplex (think that was the switch)
>> while the other PHY ended up in 100 MBps Full Duplex.
>
> That would most probably be a bug in the U-Boot ethernet driver, then.
>
> Best regards,
>
> Wolfgang Denk

If auto-negotiation fails, the default is half duplex (10 or 100 - the
speed can be discovered independent of the autonegotiation by the encoding).

Ulf's recollection that the switch was half duplex would indicate that
the cheap switch did not autonegotiate properly, but u-boot did. This
could be a u-boot bug (not setting up the negotiation properly), but
more likely would be a switch problem (not handling the u-boot auto-neg
options properly).

gvb