[U-Boot-Users] Re: tftp timeout

[Jerry Van Baren]

Andre Puschmann wrote:
> Jerry Van Baren wrote:
>> Andre Puschmann wrote:
>>
>>> hallo,
>>> i know this newsgroup already talked about this subject and of course i
>>> read this stuff but there are still some questions ..
>>>
>>> i am currently trying to download a kernel image via tftp from a
>>> tftp-server on my hostpc which is connected through a ethernet-switch.
>>> but i always get timeouts .. look at this:
>>>
>>> <log>
>>> Load address: 0x20800000
>>> Loading: *\0x08#######T ##################################T
>>> ###################T ####T ##T #
>>> \0x09 ###T #T #########T ########T #############T ##T #############T
>>> ########T #############T
>>> \0x09 #####T ###T ######T #######T #######T #############T ##T
>>> ##############T ###########
>>> \0x09 ###########
>>> done
>>> </log>
>>>
>>> i mean .. the transfer is ok .. but it takes ages :-)
>>>
>>>
>>> it looks like this if i connect my board directly to my hostpc.
>>>
>>> <log>
>>> Load address: 0x20800000
>>> Loading: *\0x08T
>>> #################################################################
>>> \0x09 #################################################################
>>> \0x09 #################################################################
>>> \0x09 ###########
>>> done
>>> </log>
>>>
>>>
>>> does anybody got the same issues?
>>> i mean there is no huge traffic on the net and my local tftp client 
>>> loads the 1MB kernel-image in seconds.
>>> i am using u-boot-1.1.1 and i also tried u-boot-1.1.4!
>>>
>>> regards
>>> andre
>>
>>
>> My guess is that you have a full duplex/half duplex problem.  Verify 
>> that your board/u-boot is setting your ethernet to the proper duplex 
>> (full/half).  I'm guessing your board is half duplex but your switch 
>> is full (typical of a switch ;-).
>>
>> The switch sends traffic to your board while your board is 
>> transmitting... that is a collision (late collision at that) to your 
>> board but is OK to the switch.  This doesn't happen nearly as much 
>> with your PC since you have a dedicated link without much asynchronous 
>> traffic.
>>
>> This is a FAQ type problem where the software (u-boot/linux) needs to 
>> poll the PHY chip for duplex and then (re)configure the MAC chip 
>> (separate or built into the CPU) to match.  If the poll isn't 
>> happening or has a bug, you have a problem.
>>
>> gvb
>>
> 
> thanks for your tip ..
> sorry i am not that introduced in how autonegotiation works but i guess 
> the function dm9161_AutoNegotiate() in dm9161.c does the related stuff.
> i mean the switch i am using is a no-name one and with an other 
> netg**r-switch it works nice, just tested it ... so it seems to be a bug 
> in that fuctions, right??
> 
> regards
> andre

As Smokey the Bear says, "Only YOU can debug your hardware."
   <http://en.wikipedia.org/wiki/Smokey_the_bear>
OK, so I'm lying, but it still is true.

Dump the MII registers and determine if your MAC is configured for full 
or half duplex in all situations:
* Powered up with the noname switch connected
* Unplug the noname switch (power applied)
* Plug in the noname switch (power applied)
* Repeat the first three steps with the Netgear switch
* Repeat the first three steps with a direct connection to your PC

Translate and correlate the register values.  The problem will probably 
show up in the differences.  Fix the problem and let us know what it was.

gvb