[U-Boot-Users] Accessing mkimage checksum

[Wolfgang Denk]

In message <200604270900.14579.ngustavson at emacinc.com> you wrote:
>
> The target board is our SoM-5282M, 
> http://www.emacinc.com/som/som5282em.htm

Maybe before asking for free help here you should feed  your  patches
back into the public tree.

> > I  don't  see 
> > why "the flashing utility needs to calculate a checksum" - the uImage
> > file  already  has  two  checksums,  so  no new calculation should be
> > needed. 
> For verification during the writing process.

You don't want to verify this  "during  the  writing  process".  This
makes  no  sense. You probably want to verify it *before* erasing the
image in flash (so that you keep the old image if the downloaded  one
was  corrupt),  and *after* writing has completed (so you can be sure
that the flash content is ok).

> > I have no idea what you could need special tools for.
> It needs to be an easy to use utility (This utility could be a shell script) 

"mkimage" is trivial to use. It just requires the "-l" option  and  a
file name argument.

> I realize it's not that complicated an issue, and I could probably figure it 
> out in an hour or two. But somebody's probably already done this, why not 
> just ask? 

I just told you: this *has* been solved. "mkimage" perfectly does the
job. No new code is needed.

> > Actually this has nothing to do with uClinux, and  very  little  with
> > U-Boot.
> It requires a small amount of knowlege of raw access to MTD, the format used 

This is standard Linux stuff and not uClinux specific.

> by mkimage, and it would be nice to know I'm not reinventing the wheel.

You don't need to know the mkimage format, as  the  mkimage  tool  is
perfectly capable of reading and checking such images.

Best regards,

Wolfgang Denk

-- 
Software Engineering:  Embedded and Realtime Systems,  Embedded Linux
Phone: (+49)-8142-66989-10 Fax: (+49)-8142-66989-80 Email: wd at denx.de
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