[U-Boot] Question about Netconsole

[Jared Lewis]

Hi Detlev-

Thank you for the response.  I will give your recommendation a try and
see how it goes.  

Thanks again,
Jared


-----Original Message-----
From: Detlev Zundel [mailto:dzu at denx.de] 
Sent: Friday, August 21, 2009 5:58 AM
To: Jared Lewis
Cc: u-boot at lists.denx.de
Subject: Re: [U-Boot] Question about Netconsole

Hi Jared,

> I have been having troubles getting Netconsole to work on eTSEC2 of a
> MPC8548 chip.  I was hoping that maybe someone here might be able to
> help me. 
>
> I'm currently using U-Boot v2009.01.  Using the bash script code
located
> in the README.Netconsole file, I have been able to successfully
transmit
> data from the 8548 to my host machine over netcat (using v0.7.1 on
> Fedora Core 11).  I've tested that this path works consistently by
only
> piping stdout to 'nc'.  
>
> My problem comes when I try to send data from the host machine to the
> 8548 (piping stdin to 'nc').  It seems like the data is getting
> transmitted by Netconsole (verified using wireshark), but it isn't
> getting consistently received by U-Boot.  I set the ET_DEBUG flag to 1
> so that I could get extra debug information.  On rare occasions I have
> seen that packets are getting received, but this is very rarely.  I do
> know that the connection is OK.  I am able to transfer files using
tftp
> without any problems.  On one occasion I was able to print out an
> environment variable (a small victory), but it happened randomly.  
>
> Does anyone have any idea why this might be happening?  Any help would
> be greatly appreciated.

You should check what your actual network driver is doing.  As U-Boot is
not interrupt driven, the big question is if and how packets on the
network
interface are buffered when U-Boot is not currently idle waiting.

Unfortunately I have to admit that I do not know the exact control flow
of netconsole coupled to the tsec driver, but what you could do is to
trace tsec_halt and startup_tsec.  Maybe they are called too often
and/or
take too long...

Cheers
  Detlev

-- 
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than bad
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