Hello @jackfrye11,
well, the source code of U-Boot is part of Intel SoC EDS in a form of archive here:
“C:\intelFPGA\18.0\embedded\host_tools\altera\bootloaders\u-boot\uboot-socfpga.tar.gz” (of course, the path depends on Yours host OS, EDS version etc.).
However, the archive is of version 2013 (but this is not important) and is not meant to be extracted by You directly. It should be extracted with a tool called bsp-editor. This tool also adjusts the source code of U-Boot according to the hardware specialities of Your Quartus Prime project. You have to execute the bsp-editor tool from SoC EDS commad Shell.
I am sorry, I could not find the documents, where this is described.
Just do:
- Open SoC EDS Commnad Shell
- Type ‘bsp-editor &’
- Follow the instruction of 4th Chapter of Embedded Linux Beginners Guide
- Post generating source code with bsp-editor type ‘cd {folder of Yours Quartus Prime project}/software/spl_bsp/’
- Type ‘make’. The preloader will be compiled (it takes some tens of seconds), so a file preloader-mkpimage.bin will appear at the folder.
- Copy the preloader somewhere, e.g. to the root directory of the Quartus Prime project
- Type ‘make uboot’. The U-Boot wil be compiled (it takes some minutes), so a file ‘uboot.img’ will appear at the folder.
- Copy the U-Boot somewhere, too.
- The Preloader an U-Boot could be copied onto Your SD card now. You could use tool called alt-boot-disk-util form SoC EDS Command Shell. If You do not know ,how to use it, type ‘alt-boot-disk-util --help’.
Hope this will help You a bit.
Yours sincerelly Jan Konečný.