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

Ulf Samuelsson ulf.samuelsson at atmel.com
Wed Jan 7 20:36:51 CET 2009


ons 2009-01-07 klockan 07:52 -0500 skrev Jerry Van Baren:
> Wolfgang Denk wrote:
> > Dear Ulf Samuelsson,
> > 
> > In message <1231282371.32308.276.camel at 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).
> 

Don't remember all details, since it was 4 years ago.
I talked to D-Link support and they claimed that the standard
was to fall back to one of the options, if autonegotiation failed.
The customer might have had a PHY without autonegotation which
was hardwired to 100 Mbps full duplex.

With little communication, the packages were sent 
where this caused some problems.


> gvb
> 
> _______________________________________________
> U-Boot mailing list
> U-Boot at lists.denx.de
> http://lists.denx.de/mailman/listinfo/u-boot


More information about the U-Boot mailing list