Currently, I build a linux kernel that contains the root fileystem in the zImage file, when then gets converted into a uImage and booted from NAND flash. This is all working fine, but having the kernel build depend on the rootfs build is a problem.
In another mailing list, somebody told me that if I was using U-Boot, I could build the zImage and rootfs separately and then combine them into a single uImage file for distribution.
I've been looking through the manual and FAQs, and can't figure out how to do this. I did find a vague reference in one of the Linux kernel docs that some bootloaders will detect any "extra" bytes after the end of the zImage data and assume that they are a rootfs image. Is that how U-Boot does it? I just cat the ziminage and rootfs.cpio.gz files together and then prepend a uImage header?