[U-Boot] [swupdate] Re: SWUpdate - U-Boot environment library dependency

[Wolfgang Denk]

Dear Simon,

In message <e7751e81-610b-9cdd-e14d-04fc5b7a297f at gmail.com> you wrote:
>
> Hmm, on my board, SPL loads U-Boot from NOR to SDRAM, then checks the 
> uimage CRC. I'd say this is enough checks. That might not hold for all 
> boards though.

If you check the image in RAM, then yes.  I've also seen
implementations where it gets checked on the fly (for boot time
reasons), so write corruption would not be covered.

> Could we put U-Boot into a fit image and put the environment in a 
> subimage? But it might increase SPL code size when a fit image has to be 
> parsed...

Yes, of course this can be done.  You would need such code anyway in
SPL if you gor for Falcon mode, where you would load a (signed) FIT
image with the Linux kernel and DTB (and maybe even a ramdisk
image).

But as mentioned - this depends on the use case and on available
resources.  It may not be possible on many more resource-constricted
boards - there, other mechanisms should be possible.

Best regards,

Wolfgang Denk

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