[U-Boot-Users] Accessing mkimage checksum

Wolfgang Denk
2006-04-26T20:14:15Z

In message <200604261502.02751.ngustavson@emacinc.com> you wrote:
> > So what is your problem - you have the image, and want to write it to
> > flash. Why would you need any additional tools for that?
> Because I want to write it through the uClinux MTD layer, which has nothing to
> do with u-boot, other than the fact that the flashing utility needs to
> calculate a checksum and verify it against the package, which is
> the "ubootian" format created by mkimage.

Maybe you explain in more detail what you intend to do. 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.

If you use the MTD layer as a blockdevice, you will probably have a
file system there; then you can just use "cp" as "flashing utility"
and "mkimage -l" to verify the checksums after writing.

If you use a character device, you can just use "cp" as "flashing
utility" and "mkimage -l" to verify the checksums after writing;
probably an additional step will be nedded to reead back the MTD
character device in a file, making sure only the original amount of
data is read back; a tiny shell script based on "ls" and "cut" and
"dd" will do).

I have no idea what you could need special tools for.

> This is really a question for both the uClinux and u-boot communities.

Actually this has nothing to do with uClinux, and very little with
U-Boot.

> If a section of what I'm asking does not apply to your work then please ignore
> it.

You post her, I reply here.

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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