[RFC] Device tree for new desktop platform in arch/powerpc

Benjamin Herrenschmidt benh at kernel.crashing.org
Thu Jun 21 22:42:13 EST 2007


On Tue, 2007-06-19 at 15:42 +1000, David Gibson wrote:
> 
> Is there a device binding defined somewhere for "chrp,iic"?

Yes, it's the standard for 8259 on chrp and chrp-like platforms.

> >               interrupt-controller;
> >               reg = <20 2 a0 2 4d0 2>;
> >               reserved-interrupts = <2>;

I'm currious about the above though, what is it ?

> >               #address-cells = <1>;

Why #address-cells set to 1 ? In a PIC node, in fact, I would expect it
to be 0 to avoid any spurrious "reg" matching for interrupts.

> >               #size-cells = <0>;
> >               #interrupt-cells = <2>;
> >       };
> 
> >       8042 at 60 {
> >               device_type = "8042";
> >               compatible = "chrp,8042";
> >               reg = <60 10>;
> >               interrupts = <1 3 c 3>;                 // IRQ1, IRQ12
> (rising edge)
> >               interrupt-parent = <&interrupt-controller>;

Just put the interrupt-parent pointer once in the isa bridge and all isa
devices below the bridge.

> This should cause a dtc error.  Either you want &/interrupt-controller
> or give the interrupt-controller node a label and refer to that.  It's
> either '&/some/full/path' or '&label'.
> 
> >               #address-cells = <1>;
> >               #size-cells = <0>;                      // No physical
> address.
> 
> Comment is arguably incorrect.

Yeah, not sure what that is supposed to be.

Ben.





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