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

Wolfgang Denk wd at denx.de
Tue Dec 18 21:11:14 CET 2007


In message <476823D1.6040104 at freescale.com> you wrote:
> Wolfgang Denk wrote:
> 
> > What good would this do to you? If you  run  a  "dhcp"  command  with
> > autostart  enabled,  the image will immediately be autobooted - there
> > will be no place for you to issue a command to do anything with  your
> > environment variable.
> 
> Wouldn't it be better to run the 'bootcmd' variable?  That's how U-Boot has 
> always autobooted.  I'm sure there are boards out there that need to run some 
> commands before booting, and they use bootcmd to do that.

Maybe that's how U-Boot has beeen booted for you in your  setup.  But
it's  just  one  of a plethora of options, including alternative boot
commands for  example  selected  by  failed  POST  or  exceeded  boot
counters, etc.

And btw: that's what I'm describing all the time. Consider the
situation where your environment has the following two variable
settings:

	autostart=yes
	bootcmd=dhcp

Which part of the code  would  you  expect  to  set  the  environment
variable  (i.  e.  in  which  part  would  you place the hook for the
plugin), and where would you add any code  to  take  notice  of  this
variable setting?


To mee it seems logical to add the hooks to the "bootm" command code,
which will have to figure out what to do with the individual parts of
the multifile image, and then setting a  variable  is  obviously  not
sufficient - you must run some code then.

Best regards,

Wolfgang Denk

-- 
DENX Software Engineering GmbH,     MD: Wolfgang Denk & Detlev Zundel
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