Re: [PATCH v4 2/3] dt-bindings: rng: add bindings for MediaTek ARMv8 SoCs

From: Neal Liu
Date: Wed Jul 24 2019 - 01:04:13 EST


On Tue, 2019-07-23 at 08:35 -0600, Rob Herring wrote:
> On Mon, Jul 22, 2019 at 8:21 PM Neal Liu <neal.liu@xxxxxxxxxxxx> wrote:
> >
>
> Please don't top post to lists.
>
> > Dear Rob,
> > You can check my driver for detail:
> > http://patchwork.kernel.org/patch/11012475/ or patchset 3/3
>
> I could, or you could just answer my question.
>
> >
> > This driver is registered as hardware random number generator, and
> > combines with rng-core.
> > We want to add one rng hw based on the dts. Is this proper or do you
> > have other suggestion to meet this requirement?
>
> It depends. There doesn't appear to be any resource configuration, so
> why does it need to be in DT. DT is not the only way instantiate
> drivers.
>
> Rob

This hwrng is only supported on some chipsets. It needs DT to identify
which platform is supported or not. Is there any better idea to meet
this requirement?

Neal

> >
> > Thanks
> >
> >
> > On Tue, 2019-07-23 at 01:13 +0800, Rob Herring wrote:
> > > On Mon, Jun 24, 2019 at 03:24:11PM +0800, Neal Liu wrote:
> > > > Document the binding used by the MediaTek ARMv8 SoCs random
> > > > number generator with TrustZone enabled.
> > > >
> > > > Signed-off-by: Neal Liu <neal.liu@xxxxxxxxxxxx>
> > > > ---
> > > > .../devicetree/bindings/rng/mtk-sec-rng.txt | 10 ++++++++++
> > > > 1 file changed, 10 insertions(+)
> > > > create mode 100644 Documentation/devicetree/bindings/rng/mtk-sec-rng.txt
> > > >
> > > > diff --git a/Documentation/devicetree/bindings/rng/mtk-sec-rng.txt b/Documentation/devicetree/bindings/rng/mtk-sec-rng.txt
> > > > new file mode 100644
> > > > index 0000000..c04ce15
> > > > --- /dev/null
> > > > +++ b/Documentation/devicetree/bindings/rng/mtk-sec-rng.txt
> > > > @@ -0,0 +1,10 @@
> > > > +MediaTek random number generator with TrustZone enabled
> > > > +
> > > > +Required properties:
> > > > +- compatible : Should be "mediatek,mtk-sec-rng"
> > >
> > > What's the interface to access this?
> > >
> > > A node with a 'compatible' and nothing else is a sign of something that
> > > a parent device should instantiate and doesn't need to be in DT. IOW,
> > > what do complete bindings for firmware functions look like?
> > >
> > > > +
> > > > +Example:
> > > > +
> > > > +hwrng: hwrng {
> > > > + compatible = "mediatek,mtk-sec-rng";
> > > > +}
> > > > --
> > > > 1.7.9.5
> > > >
> > >
> > > _______________________________________________
> > > Linux-mediatek mailing list
> > > Linux-mediatek@xxxxxxxxxxxxxxxxxxx
> > > http://lists.infradead.org/mailman/listinfo/linux-mediatek
> >
> >