[U-Boot-Users] Ensuring correctness of U-boot in the flash

[Wolfgang Denk]

In message <12751790.post at talk.nabble.com> you wrote:
> 
> > The environment is a convenient place,  unless  your  environment  is
> > embedded within U-Boot, in which case you need to split this up
> > anyway.
> 
> Won't work in our case I'm afraid. First, we would like the booted
> application to be able to check the CRC after upgrading U-boot, which means
> that it will need to know the environment structure (something that is also
> problematic legally, as some of our applications are non GPL). Second, our

I don't understand why this should be a problem. Reading the
environment can be done by separate tools lile fw_printenv (see
tools/env/).

> master plan is to have two copies of U-boot programmed on the flash (for
> field upgrades sake), with a mutual environment sector.

So  you  have  some  primary  bootstrap  loader  which  performs  the
selection  and  switching? Well, sounds overly complicated to me, but
it's your choice.

> I guess the only way to implement this meeting our requirements is to
> sacrifice an adjacent sector that will only hold the CRC.

Why don't you enable the MD5 checksum feature then? It uses an
embedded (in the image) MD5 checksum.

Best regards,

Wolfgang Denk

-- 
DENX Software Engineering GmbH,     MD: Wolfgang Denk & Detlev Zundel
HRB 165235 Munich, Office: Kirchenstr.5, D-82194 Groebenzell, Germany
Phone: (+49)-8142-66989-10 Fax: (+49)-8142-66989-80 Email: wd at denx.de
To know how another being, another creature feels -  that  is  impos-
sible.                  - Terry Pratchett, _The Dark Side of the Sun_