[U-Boot-Users] Multicast TFTP problems

[Rafal Jaworowski]

Dave,

I'm having problems with tftp transfer with current U-Boot running on 
MPC5121 (FEC controller); since your mcast tftp implementation we first 
attempt to transfer using some bigger blocksize:
#define TFTP_MTU_BLOCKSIZE 1468, and it seems my problems are related to 
this size.

When running current code (ET_DEBUG enabled) it fails like the following:

=> run load
Using FEC ETHERNET device
TFTP from server 192.168.1.1; our IP address is 192.168.160.77
Filename '/tftpboot/ads5121/u-boot.bin'.
Load address: 0x100000
Loading: send option "timeout 5"
Got OACK: timeout 5
Blocksize ack: 1468, 1468
T T T T T T T T T T
Retry count exceeded; starting again
Using FEC ETHERNET device
TFTP from server 192.168.1.1; our IP address is 192.168.160.77
Filename '/tftpboot/ads5121/u-boot.bin'.
Load address: 0x100000
Loading: send option "timeout 5"
Got OACK: timeout 5
Blocksize ack: 1468, 1468

Abort
=>

It fails with TFTP_MTU_BLOCKSIZE values above 1454, but it's ok with 
anything up to this (including 1454):

=> run load
Using FEC ETHERNET device
TFTP from server 192.168.1.1; our IP address is 192.168.160.77
Filename '/tftpboot/ads5121/u-boot.bin'.
Load address: 0x100000
Loading: send option "timeout 5"
Got OACK: timeout 5
Blocksize ack: 1454, 1454
###########
done
Bytes transferred = 157720 (26818 hex)
=>

Any hints on these observations? What might be going wrong here?

kind regards,
Rafal