[U-Boot] [PATCH 3/6] mpc83xx: Add link vs. load address calculation

[Joakim Tjernlund]

Scott Wood <scottwood at freescale.com> wrote on 2010/11/23 21:17:12:
>
> On Tue, 23 Nov 2010 21:08:37 +0100
> Joakim Tjernlund <joakim.tjernlund at transmode.se> wrote:
>
> > Scott Wood <scottwood at freescale.com> wrote on 2010/11/23 20:32:32:
> > > On Tue, 23 Nov 2010 19:48:48 +0100
> > > Joakim Tjernlund <Joakim.Tjernlund at transmode.se> wrote:
> > >
> > > > diff --git a/include/common.h b/include/common.h
> > > > index 8bca04f..f257ea4 100644
> > > > --- a/include/common.h
> > > > +++ b/include/common.h
> > > > @@ -94,6 +94,9 @@ typedef volatile unsigned char   vu_char;
> > > >  #ifdef CONFIG_MPC83xx
> > > >  #include <mpc83xx.h>
> > > >  #include <asm/immap_83xx.h>
> > > > +const void * link_off(const void *);
> > > > +#else
> > > > +#define link_off(x) ((const void *)(x))
> > > >  #endif
> > >
> > > What is special about 83xx?
> >
> > Nothing, just it is the first one.
> > >
> > > If it's just that 83xx is the only one that this type of relocation has
> > > been enabled on so far, define a symbol for that.
> >
> > there is a
> > #define LINK_OFF(x) ((__typeof__(x))link_off(x))
> > already but I am guessing you mean something else.
> > Perhaps a dummy link_off for other targets? Don't think
> > that is any better.
>
> I mean instead of this:
>
> #ifdef CONFIG_MPC83xx
> ...unrelated stuff...
> const void *link_off(const void *ptr);
> #else
> #define link_off(x) ((const void *)(x));
> #endif
>
> do something like this:
>
> #ifdef CONFIG_RELOC_PIC
> const void *link_off(const void *ptr);
> #else
> #define link_off(x) ((const void *)(x));
> #endif
>
> ...with CONFIG_RELOC_PIC defined in a board config file and also
> controlling whether this mechanism is enabled at all.  Boards could
> enable it as they verify that they have the proper manual relocations
> (or just leave it off, if they don't think it's worth it) -- including
> non-83xx targets if they provide link_off() and do whatever else is
> required.

Ah yes, will be in my cleanup later on.