[PATCH v2 10/13] dt-bindings: riscv: Add Sha and its comprised extensions

[Guodong Xu]

Hi, Alex

On Sat, Dec 27, 2025 at 5:28 AM Alex Elder <elder at riscstar.com> wrote:
>
> On 12/22/25 7:04 AM, Guodong Xu wrote:
> > Add descriptions for the Sha extension and the seven extensions it
> > comprises: Shcounterenw, Shgatpa, Shtvala, Shvsatpa, Shvstvala, Shvstvecd,
> > and Ssstateen.
> >
> > Sha is ratified in the RVA23 Profiles Version 1.0 (commit 0273f3c921b6
> > "rva23/rvb23 ratified") as a new profile-defined extension that captures
> > the full set of features that are mandated to be supported along with
> > the H extension.
> >
> > Extensions Shcounterenw, Shgatpa, Shtvala, Shvsatpa, Shvstvala, Shvstvecd,
> > and Ssstateen are ratified in the RISC-V Profiles Version 1.0 (commit
> > b1d806605f87 "Updated to ratified state").
> >
> > The requirement status for Sha and its comprised extension in RISC-V
> > Profiles are:
> >   - Sha: Mandatory in RVA23S64
> >   - H: Optional in RVA22S64; Mandatory in RVA23S64
> >   - Shcounterenw: Optional in RVA22S64; Mandatory in RVA23S64
> >   - Shgatpa: Optional in RVA22S64; Mandatory in RVA23S64
> >   - Shtvala: Optional in RVA22S64; Mandatory in RVA23S64
> >   - Shvsatpa: Optional in RVA22S64; Mandatory in RVA23S64
> >   - Shvstvala: Optional in RVA22S64; Mandatory in RVA23S64
> >   - Shvstvecd: Optional in RVA22S64; Mandatory in RVA23S64
> >   - Ssstateen: Optional in RVA22S64; Mandatory in RVA23S64
> >
> > Add schema checks to enforce that Sha implies the presence of all its
> > comprised extensions.
>
> Like patch 7 in your series, I *think* what you're doing
> in trying to imply the presence of these other extensions
> is actually requiring all those extensions to be present
> *in addition* to just "Sha".  I don't think that's what
> we want.

I tend to think this schema check block should be removed. Conor expressed
similar design logic in his comments to my Patch 7/13 of v2 series.

If there is no objection, I will remove it.

BR,
Guodong


>
>                                         -Alex
>
> > Signed-off-by: Guodong Xu <guodong at riscstar.com>
> > ---
> > v2: New patch.
> > ---
> >   .../devicetree/bindings/riscv/extensions.yaml      | 79 ++++++++++++++++++++++
> >   1 file changed, 79 insertions(+)
> >
> > diff --git a/Documentation/devicetree/bindings/riscv/extensions.yaml b/Documentation/devicetree/bindings/riscv/extensions.yaml
> > index ed7a88c0ab3b7dc7ad4a4d2fd300d6fb33ef050c..1066b7e65dab89704dbac449db4aa5605c95b9d3 100644
> > --- a/Documentation/devicetree/bindings/riscv/extensions.yaml
> > +++ b/Documentation/devicetree/bindings/riscv/extensions.yaml
> > @@ -128,6 +128,57 @@ properties:
> >               version of the privileged ISA specification.
> >
> >           # multi-letter extensions, sorted alphanumerically
> > +        - const: sha
> > +          description: |
> > +            The standard Sha extension for augmented hypervisor extension as
> > +            ratified in RVA23 Profiles Version 1.0, with commit 0273f3c921b6
> > +            ("rva23/rvb23 ratified").
> > +
> > +            Sha captures the full set of features that are mandated to be
> > +            supported along with the H extension. Sha comprises the following
> > +            extensions: H, Shcounterenw, Shgatpa, Shtvala, Shvsatpa, Shvstvala,
> > +            Shvstvecd, and Ssstateen.
> > +
> > +        - const: shcounterenw
> > +          description: |
> > +            The standard Shcounterenw extension for support writable enables
> > +            in hcounteren for any supported counter, as ratified in RISC-V
> > +            Profiles Version 1.0, with commit b1d806605f87 ("Updated to
> > +            ratified state.")
> > +
> > +        - const: shgatpa
> > +          description: |
> > +            The standard Shgatpa extension indicates that for each supported
> > +            virtual memory scheme SvNN supported in satp, the corresponding
> > +            hgatp SvNNx4 mode must be supported. The hgatp mode Bare must
> > +            also be supported. It is ratified in RISC-V Profiles Version 1.0,
> > +            with commit b1d806605f87 ("Updated to ratified state.")
> > +
> > +        - const: shtvala
> > +          description: |
> > +            The standard Shtvala extension for htval be written with the
> > +            faulting guest physical address in all circumstances permitted by
> > +            the ISA. It is ratified in RISC-V Profiles Version 1.0, with
> > +            commit b1d806605f87 ("Updated to ratified state.")
> > +
> > +        - const: shvsatpa
> > +          description: |
> > +            The standard Shvsatpa extension for vsatp supporting all translation
> > +            modes supported in satp, as ratified in RISC-V Profiles Version 1.0,
> > +            with commit b1d806605f87 ("Updated to ratified state.")
> > +
> > +        - const: shvstvala
> > +          description: |
> > +            The standard Shvstvala extension for vstval provides all needed
> > +            values as ratified in RISC-V Profiles Version 1.0, with commit
> > +            b1d806605f87 ("Updated to ratified state.")
> > +
> > +        - const: shvstvecd
> > +          description: |
> > +            The standard Shvstvecd extension for vstvec supporting Direct mode,
> > +            as ratified in RISC-V Profiles Version 1.0, with commit b1d806605f87
> > +            ("Updated to ratified state.")
> > +
> >           - const: smaia
> >             description: |
> >               The standard Smaia supervisor-level extension for the advanced
> > @@ -186,6 +237,12 @@ properties:
> >               ratified at commit d70011dde6c2 ("Update to ratified state")
> >               of riscv-j-extension.
> >
> > +        - const: ssstateen
> > +          description: |
> > +            The standard Ssstateen extension for supervisor-mode view of the
> > +            state-enable extension, as ratified in RISC-V Profiles Version 1.0,
> > +            with commit b1d806605f87 ("Updated to ratified state.")
> > +
> >           - const: sstc
> >             description: |
> >               The standard Sstc supervisor-level extension for time compare as
> > @@ -813,6 +870,28 @@ properties:
> >                   const: zbb
> >               - contains:
> >                   const: zbs
> > +      # sha comprises the following extensions
> > +      - if:
> > +          contains:
> > +            const: sha
> > +        then:
> > +          allOf:
> > +            - contains:
> > +                const: h
> > +            - contains:
> > +                const: shcounterenw
> > +            - contains:
> > +                const: shgatpa
> > +            - contains:
> > +                const: shtvala
> > +            - contains:
> > +                const: shvsatpa
> > +            - contains:
> > +                const: shvstvala
> > +            - contains:
> > +                const: shvstvecd
> > +            - contains:
> > +                const: ssstateen
> >         # Zcb depends on Zca
> >         - if:
> >             contains:
> >
>