[U-Boot-Users] [PATCH] Blackfin: implement go/boote wrappers

Wolfgang Denk wd at denx.de
Mon Apr 21 12:07:49 CEST 2008


In message <200804210541.41085.vapier at gentoo.org> you wrote:
>
> > This makes no sense. If it is ``exactly like "go"'' it doesn't matter
> > if the code returns or not (and actually this is what I'm  trying  to
> > point out all the time).
> 
> the obvious implication is that i would add the cache disabling hooks to the 
> jump command instead of the go command since you wont allow the hook around 
> go.

So it would NOT be ``exactly like "go"''.

Providing both a "go" and a "jump" command which differ just in cahce
handling seems broken to me. If you want to add such a feature,  then
I recommend to do it as part of "go", but make it optional, i. e. in-
troduce a new optional argument to the "go" command, something like

	go [ -cache={off,d-off,i-off,on,d-on,i-on} ] addr [ args ... ]

> > It's just that "go" shall retain the standard U-Boot environment for
> > application it runs, and that the applications need to take care if
> > they need to meddle with interrupts, exception handlers, etc.
> 
> U-Boot sets up no interrupts and the only exceptions that occur on the 
> Blackfin are for cache handling.  disabling the caches forces a sane 

There is more procvessors in  this  world  than  just  Blackfin,  and
others  *do*  enable  interrupts,  etc.  It  is  important to me that
implementations behave the same no matter which architecture you  are
using.


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
Where there's no emotion, there's no motive for violence.
	-- Spock, "Dagger of the Mind", stardate 2715.1




More information about the U-Boot mailing list