We plan on using uboot it to boot an embedded application (no OS) from flash memory. We would like to extend uboot to be able to download a new application program via a proprietary dual-port memory interface (custom serial protocol implemented in FPGA). My reading of the GPL suggests that adding this type of functionality directly to uboot would be considered a derivative work thus requiring the submission of the code, regardless of the usefulness of the extension to anyone else. Is my understanding correct?
In order to avoid this GPL compliance issue, is it permissible/possible to add a stand alone program (i.e. hello world) that would be run automatically at startup. The standalone program we be conceptually similar to bootp. Should the custom standalone program not find software to load, we would want uboot to resume control of the system and continue trying to boot from flash memory. Is this consistent with the intent of the stand alone program support?
Any other feedback or suggestions are is/are welcome.
Mark