Re: [PATCH v2 1/2] dt-bindings: arm,gic: Fix binding example for a virt-capable GIC

From: Olof Johansson
Date: Sun Jan 29 2017 - 19:16:28 EST


On Fri, Jan 27, 2017 at 02:30:01PM -0600, Rob Herring wrote:
> On Mon, Jan 23, 2017 at 03:56:13PM +0000, Marc Zyngier wrote:
> > The joys of copy/paste: the example of a virtualization capable GIC
> > in the DT binding was wrong, and propagated to dozens of platforms.
> > By having a GICC region that is only 4kB (instead of 8kB), we
> > end-up not being able to access the GICC_DIR register which is on
> > the second page.
> >
> > Oh well. Let's fix the source of the crap before tackling individual
> > offenders. While we're at it, also fix the compatibility string to
> > mention "arm,gic-400", which is the name of the actual implementation
> > of the GICv2 spec.
>
> "While we're at it", code for should be in a separate patch. :) I
> wouldn't really care here, but you are not fixing anything...
>
> >
> > Acked-by: Tony Lindgren <tony@xxxxxxxxxxx>
> > Acked-by: Mark Rutland <mark.rutland@xxxxxxx>
> > Acked-by: Arnd Bergmann <arnd@xxxxxxxx>
> > Signed-off-by: Marc Zyngier <marc.zyngier@xxxxxxx>
> > ---
> > Documentation/devicetree/bindings/interrupt-controller/arm,gic.txt | 4 ++--
> > 1 file changed, 2 insertions(+), 2 deletions(-)
> >
> > diff --git a/Documentation/devicetree/bindings/interrupt-controller/arm,gic.txt b/Documentation/devicetree/bindings/interrupt-controller/arm,gic.txt
> > index 5393e2a..a3d51ed 100644
> > --- a/Documentation/devicetree/bindings/interrupt-controller/arm,gic.txt
> > +++ b/Documentation/devicetree/bindings/interrupt-controller/arm,gic.txt
> > @@ -107,11 +107,11 @@ Required properties:
> > Example:
> >
> > interrupt-controller@2c001000 {
> > - compatible = "arm,cortex-a15-gic";
> > + compatible = "arm,gic-400";
>
> Which one is correct really depends on the platform. The A15 can have an
> internal or external (gic-400) GIC. The former string is correct for an
> A15 with an internal GIC. One such platform is Calxeda midway.
>
> Arguably, we should not have arm,gic-400 by itself, but have an SoC
> specific compatible in case it was integrated in interesting ways.

Good point (and thanks for bringing it up).

Marc, based on this; want to back the above out so we can apply the rest for
now, while you battle on the compatible details? :)


-Olof