[U-Boot] [patch/rfc] rm9200 lowevel_init: don't touch reserved/readonly registers

Wolfgang Denk wd at denx.de
Fri Jul 10 22:49:33 CEST 2009


Dear David Brownell,

In message <200906282241.54948.david-b at pacbell.net> you wrote:
> On Tuesday 09 June 2009, David Brownell wrote:
> > For some reason the AT91rm9200 lowlevel init writes to a bunch of
> > reserved or read-only addresses.  All the boards seem to define the
> > value-to-be-written values as zero ... but they shouldn't actually
> > be writing *anything* there.
> 
> Repeat:  should not write to reserved or read-ony addresses.
> 
> 
> > If there's a real need to write these locations, like an erratum
> > that's not included in the current list, that should be reflected
> > in a source code comment.  Looks like maybe some very early BDI-2000
> > setup code has been carried along by cargo cult programming since
> > at least late 2004 (per GIT history).
> > 
> > Meanwhile, here's a patch/RFC disabling what seems to be bogosity.
> > If it's eventually a "go", the supporting code should be removed.
> 
> No comments?

If no comments come for a patch-RFC for some days, you should try and
re-post itas a real patch.

Best regards,

Wolfgang Denk

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