[U-Boot] potential Uboot Ping problem

[Peter Tyser <ptyser@xes-inc.com>]

Hi Steven,

On Mon, 2009-06-01 at 08:03 -0700, Steven Zedeck wrote:
> I guess thats good news. I looked inside the cmd_ping code a bit. I bet
> there's a "while" loop somewhere that is waiting for something and may not
> have a timeout loop. Any ideas?
> 
> Thanks,
> Steve

Please don't top post, it makes the conversation hard to follow.
http://www.caliburn.nl/topposting.html

> Premi, Sanjeev wrote:
> > 
> >> -----Original Message-----
> >> From: u-boot-bounces at lists.denx.de 
> >> [mailto:u-boot-bounces at lists.denx.de] On Behalf Of Steven Zedeck
> >> Sent: Monday, June 01, 2009 8:05 PM
> >> To: u-boot at lists.denx.de
> >> Subject: [U-Boot] potential Uboot Ping problem
> >> 
> >> 
> >> Hi,
> >> It appears the ping in UBOOT is broken. The ping works fine 
> >> if you have a
> >> network connection. But if the network connection is 
> >> disconnected the ping
> >> hangs the system. There is no response to Control-C either. I 
> >> have to power
> >> cycle the proto to get back to a UBOOT prompt. Is this a 
> >> known issue or did
> >> I possibly break something?
> >> 
> >> I have a board based on the Atmel AT91SAM9RL-EK. My theory is 
> >> that it "may"
> >> be a generic problem with the uboot ping. I can't confirm 
> >> that since the
> >> only hardware I have is our protos.
> > 
> > It was noticed on the OMAP3EVM last FRI and we were suspecting
> > it to be problem with the omap3 board configuration itself.
> > (Though did not spend much time in debug).
> > 
> > Now, I too get a feeling that it could be a generic problem.
> > 
> > Best regards,
> > Sanjeev
> >> 
> >> Does anyone else have a board with another MAC/PHY that you 
> >> can try this on?

Ideally, if there is no link, the ping command should just exit
gracefully without attempting network operations.  Eg on my 8561-based
board with no cables plugged in:
=> ping 192.168.1.1
Auto-neg error, defaulting to 10BT/HD
eTSEC1: No link.
Auto-neg error, defaulting to 10BT/HD
eTSEC2: No link.
ping failed; host 192.168.1.1 is not alive

<there is no delay in the printing of the above info>.

The tsec driver's init function returns -1 when link isn't detected.
Perhaps your ethernet driver should do the same?

What happens if you ping a non-existent IP address?  Does that also hang
the board?  Do other network operations hang the board if no ethernet
cable is plugged in?

Best,
Peter