I finally got this to work. In short, I began with a branch of the Samsung Artik 710 vesion of U-boot and made a variety of modifications. There was a bug in the way U-boot was setting up the MMU that prevented it from correctly accessing the second 512M of ram (each page table entry covers 512M). T...

Yep, the Artik 710 resources can be helpful and informative given that the Artik 710 also uses the s5p6818.
I've also spent some time looking for the sources for fip-loader.img and fip-secure.img. No luck yet.
It does look like there is an Artik repository on Github with sources for bl1-mmcboot.bin.

Hello, I posted this earlier this week on the main Fire3 forum, then realized there was a specific boot forum, so I thought I would post here also. Still busy with this, but eager for any comments. I am working with a Nanopi Fire3 with the s5p6818 chip. I do not intend to run linux (but have verifie...

Hello, I am working with a Nanopi Fire3 with the s5p6818 chip. I do not intend to run linux (but have verified operation of my board by booting linux from and SD card). What I want to do is to set up U-Boot for network booting. Ulimately I intend to port a RTOS of my own to the board. I have discove...