[PATCH 1/2] ARM: kirkwood: Basic support for DNS-320 and DNS-325

Jason Cooper jason at lakedaemon.net
Mon Mar 12 12:10:04 EDT 2012


On Mon, Mar 12, 2012 at 08:11:22AM +0000, Arnd Bergmann wrote:
> On Monday 12 March 2012, Jason Cooper wrote:
> > > Or even use the ranges property to remap everything into
> > > a simpler address range:
> > > 
> > >       ocp at f1000000 {
> > >               compatible = "simple-bus";
> > >               ranges = <0 0xf1000000 0x1000000>;
> > >               #address-cells = 1;
> > >               #size-cells = 1;
> > > 
> > >               serial at 12000 {
> > >                       reg = <0x12000 0x100>;
> > >                       ...
> > >               };
> > > 
> > >               ...
> > >       };
> > 
> > Okay, that's pretty slick.  The wdt and intc are at 0xfed00000, is that
> > another ocp bus?  Or, am I missing something?
> 
> If they are on those addresses, yes. If you have a data sheet, you should
> look at what the buses are named there, "ocp" was just an example and I
> took that name from the <mach/kirkwood.h> file.
> 
> It does seem though that the 0xfed00000 address is where Linux maps
> the same 0xf1000000 range in its own virtual address space, so it's
> not something that should appear in the device tree.

Okay, that's what smelled funny.  wdt and intc both only have registers
in virtual address space defined.  Can I assume they map like everything
else to corresponding physical addresses?

eg wdt at fed20300 -> wdt at f1020300 ?

thx,

Jason.



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