[U-Boot] Slow tftp boot with Ubuntu 12.04 tftp server

[Andrew Dyer]

On Thu, Jan 17, 2013 at 5:19 AM, David Aldrich
<David.Aldrich at emea.nec.com>wrote:

> Hi
>
> I am using an Advantech TMX320TCI6614 EVM to develop code for an ARM core
> on a TI C66x device.  The ARM core runs:
>
> U-Boot 2011.06-00002-gc4611c1-dirty (May 30 2012 - 15:38:01)
>
> I have booted this target card for several months from a tftp server
> running under Ubuntu 10.04, with no problems.  But, this week, I have tried
> to move to a tftp server that runs on a different machine running Ubuntu
> 12.04 LTS.
>
> Since moving to Ubuntu 12.04 the tftp download is very slow, although it
> does succeed eventually.  I have tried getting the boot files using a tftp
> client running on another Ubuntu host and the download is fast.
>
> Please can anyone suggest a reason for the slow download when using the
> EVM with the 12.04 server?
>

TFTP is a very simple protocol and proceeds in lock step - get a request,
send a block, wait for an ack of the last block, send the next block, etc.
 If either side times out, it will retry, but it can take quite a while.  I
would suggest to do some logging on the tftp server side or run wireshark
or tcpdump and look for retries.