Re: [PATCH v5 11/14] dt-bindings: riscv: add MMU Standard Extensions support for Svpbmt

[Heiko Stuebner]

Am Freitag, 4. Februar 2022, 23:33:42 CET schrieb Rob Herring:
> On Fri, Jan 21, 2022 at 05:36:15PM +0100, Heiko Stuebner wrote:
> > From: Wei Fu <wefu@xxxxxxxxxx>
> > 
> > Previous patch has added svpbmt in arch/riscv and add "riscv,svpmbt"
> > in the DT mmu node. Update dt-bindings related property here.
> > 
> > Signed-off-by: Wei Fu <wefu@xxxxxxxxxx>
> > Co-developed-by: Guo Ren <guoren@xxxxxxxxxx>
> > Signed-off-by: Guo Ren <guoren@xxxxxxxxxx>
> > Signed-off-by: Heiko Stuebner <heiko@xxxxxxxxx>
> > Cc: Anup Patel <anup@xxxxxxxxxxxxxx>
> > Cc: Palmer Dabbelt <palmer@xxxxxxxxxxx>
> > Cc: Rob Herring <robh+dt@xxxxxxxxxx>
> > ---
> >  Documentation/devicetree/bindings/riscv/cpus.yaml | 10 ++++++++++
> >  1 file changed, 10 insertions(+)
> > 
> > diff --git a/Documentation/devicetree/bindings/riscv/cpus.yaml b/Documentation/devicetree/bindings/riscv/cpus.yaml
> > index aa5fb64d57eb..3ad2593f1400 100644
> > --- a/Documentation/devicetree/bindings/riscv/cpus.yaml
> > +++ b/Documentation/devicetree/bindings/riscv/cpus.yaml
> > @@ -63,6 +63,16 @@ properties:
> >        - riscv,sv48
> >        - riscv,none
> >  
> > +  mmu:
> 
> riscv,mmu
> 
> > +    description:
> > +      Describes the CPU's MMU Standard Extensions support.
> > +      These values originate from the RISC-V Privileged
> > +      Specification document, available from
> > +      https://riscv.org/specifications/
> > +    $ref: '/schemas/types.yaml#/definitions/string'
> > +    enum:
> > +      - riscv,svpbmt
> 
> Are there per vendor MMU extensions? If not, drop the 'riscv,' part. 

Judging by the somewhat wild-west nature, I guess there might already
be non-riscv extensions existing somewhere, or at least the probability
is quite high that there will be in the future ;-)

> 
> > +
> >    riscv,isa:
> >      description:
> >        Identifies the specific RISC-V instruction set architecture
>