Re: [PATCH v3 11/11] arm64: dts: qcom: sc7180: Add pdc interrupt controller

From: Bjorn Andersson
Date: Mon Nov 04 2019 - 01:34:46 EST


On Sun 03 Nov 22:17 PST 2019, Rajendra Nayak wrote:

>
>
> On 10/31/2019 1:20 AM, Matthias Kaehlcke wrote:
> > On Tue, Oct 29, 2019 at 09:50:40AM -0700, Stephen Boyd wrote:
> > > Quoting Rajendra Nayak (2019-10-23 02:02:19)
> > > > From: Maulik Shah <mkshah@xxxxxxxxxxxxxx>
> > > >
> > > > Add pdc interrupt controller for sc7180
> > > >
> > > > Signed-off-by: Maulik Shah <mkshah@xxxxxxxxxxxxxx>
> > > > Signed-off-by: Rajendra Nayak <rnayak@xxxxxxxxxxxxxx>
> > > > ---
> > > > v3:
> > > > Used the qcom,sdm845-pdc compatible for pdc node
> > >
> > > Everything else isn't doing the weird old compatible thing. Why not just
> > > add the new compatible and update the driver? I guess I'll have to go
> > > read the history.
> >
> > Marc Zyngier complained on v2 about the churn from adding compatible
> > strings for identical components, and I kinda see his point.
> >
> > I agree that using the 'sdm845' compatible string for sc7180 is odd too.
> > Maybe we should introduce SoC independent compatible strings for IP blocks
> > that are shared across multiple SoCs? If differentiation is needed SoC
> > specific strings can be added.
>
> Sure, I will perhaps add a qcom,pdc SoC independent compatible to avoid
> confusion.
>

I agree,

compatible = "qcom,sc7180-pdc", "qcom,pdc";

is the way to go.

Reusing qcom,sdm845-pdc would prevent us from tackling any unforeseen
issues/variations/erratas with one or the other platform in the future.

Regards,
Bjorn

>
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