In message 9BB2AECBBDD3E6499663C42C1DFD40AAE496C5@PETWM02.calix.local you wrote:
I am trying to see if u-boot allows to have a single partition for both kernel and file system in NAND Flash.
Yes, you can do this. If it makes sense, depends on a lot of factors. Usually it does not.
Currently, I am looking at two possible approaches:
- add an extra partition in the NAND flash and keep the second kernel
in there and have some way in u-boot to decide which one to load.
That's the standard approach and works just fine, even in fancy setups like bootcnt triggered automatic fallback scenarios. It's simple, and fast.
- if u-boot allows, have one single partition for both kernel and file
system and upload both kernel images and have a soft link to a kernel image.
I'm not sure if the softlink idea works, but you can just switch the image filename in U-Boot. Works well, too, but is one of the slowest ways to boot a system.
I can't find a way to do the second option above, but that would be
Why not? It's a two-step procedure: first load the image to RAM, then bootm it...
ideal for field upgrade. Has anyone tried either of these approaches or have any other idea of how to do this? I am new to using u-boot and linux.
I tend to disagree that it's "ideal". But it can be done.
Best regards,
Wolfgang Denk