[U-Boot-Users] RFC: New U-boot image format

Wolfgang Denk wd at denx.de
Thu Dec 20 20:42:58 CET 2007

In message <4769258D.6090709 at semihalf.com> you wrote:
> The hooks idea sounds reasonable but, the problem
> is that there isn't really any such thing like
> "main fromat processing code".
> The 'bootm' command code does a lot of image
> related manipulation but it's not generic or main
> format processing code. It is rather a specialized

But it's *the* generic command for booting a Linux kernel.

> command that handles one thing, starting
> executables, like kernels or standalone
> applications. And it's a command, it will not do
> anything unless directly called.


> So, having hooks in bootm, you would need to call
> bootm and then your 'qe fw' command which is sort
> of wired.

MY current understandign is, that when  running  "bootm",  the  bootm
command  would detect if there are registred hook routines for any of
the contained sub-images, and run that code automagically.

> There are also other commands that deal with the
> images, these are other boot commands like
> scsiboot, usbboot, etc, and also imls, imxtract.

scsiboot, usbboot etc. are just means to load an image into RAM,
similar to tftpboot or dhcpboot. If they also boot the loaded image
(because autostart is set to yes), then they do so by calling bootm
internally. So everything is fine.

imls would probably have it's ownset of image type hooks - while  you
would  register some "boot me" type of handlers with bootm, you would
register some "display me" type of handlers with imls.

imxtract will have to be changed completely in any case.

> And all of them process images directly, finding
> necessary information on their own.

This is no argument for not  creating  some  more  centralized  image
processing code, or is it?

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
By the way, ALL software projects are done by iterative  prototyping.
Some companies call their prototypes "releases", that's all.

More information about the U-Boot mailing list