I am using a Riotboard and I created a complete BSP with buildroot version 2016.05 with success.
I flashed the images (u-boot, the dtb file, kernel image and tarball) successfully with MfgTool2 on eMMC media.
The board startup successfully, at this part the configuration is ok for me.
After that I would like to start in network mode, so I created an NFS server on my virtual machine.
The u-boot version I used is the default version proposed by buildroot -> 2015.10
I set these environment variable for u-boot:
ethaddr, ipaddr, serverip, netmask
=> note the there is a first issue with saveenv because after a reset the u-boot won't start.
when I type run netboot or ping and address I have this message:
ARP Retry count exceeded
I tried many version of the u-boot with the same environment. Finally with u-boot.2013.04 I can ping and start from network. This asserting that my configuration for NFS and network is correct (I use fixed IP addresses). But the version 2013.04 of u-boot make many timeouts during tftp transfers.
My question is: what is missing in the recent version of u-boot, example 2015.10 to let the network functioning?
Thanks for you help, there is a long time I try to resolve this issue, I net to make developments on the Riotboard and flashing each time is not a quick process to me.