Update regarding the buildroot I attempted a couple of weeks ago. I think I had a few different issues that prevented my last attempt to be successful.
This time I followed the steps in this release to successfully make buildroot and install it on one of my boxes.
http://openlinux.amlogic.com/wiki/in...oot-2016-12-30
This box is ENY EM95 with S905, 1GB RAM and Gigabit ethernet. I used GXBB_p200 for dtb file and can successfully boot using buildroot, get gigabit ethernet connectivity. The only issue is that HDMI does not display anything on monitor. I suspect this is due to faulty HDMI on the board because none of the other distro's are displaying on the monitor either.
The only way I can be certain that buildroot I made is good for display is by installing it on another board to test. The other board I have is an ENY EM95 with 2GB RAM and gigabit ethernet.
Unfortunately, this board fails to boot. I think this may be due to incorrect DTB file - I am using GXBB_p200. How do I find out which DTB file to use for this board ?
I've tried Armbian with GXBB_p200_2G and that does boot alright. So I used GXBB_P200_2g.dtb while installing buildroot and it still fails to boot.
I have a few other boards and will look into installing buildroot on them to try this out later.

I should add - this time I installed the Buildroot using Amlogic USB burning tool and that was successful.
Is there any way for me to unpack aml_upgrade_package.img so I can insert different dtb files in the package one by one and write to this second board (ENY EM95 2G) ?
In my post a few minutes ago - when I said I tried different dtb files, I meant using the instructions to install buildroot to eMMC via SD card. This process has not been as much fool proof as the USB burning method, that's why I'd prefer the USB burning method if I can get the dtb file inserted in that image.