Re: [PATCH v2 1/3] dt-bindings: riscv: Add Supm extension description

[Conor Dooley <conor@kernel.org>]

[-- Attachment #1: Type: text/plain, Size: 2896 bytes --]

On Sun, Jan 25, 2026 at 09:36:06AM +0800, Guodong Xu wrote:
> Add description for the Supm extension. Supm indicates support for pointer
> masking in user mode. Supm is mandatory for RVA23S64.
> 
> Add dependency check that Supm requires either Smnpm or Ssnpm.
> 
> The Supm extension is ratified in commit d70011dde6c2 ("Update to ratified
> state") of riscv-j-extension.
> 
> Signed-off-by: Guodong Xu <guodong@riscstar.com>

FWIW, this is missing my 6.20/7.0 (whichever it ends up being) PR cos
I'd like some other folks to look at the series. If Paul/Palmer are
happy with it though,
Acked-by: Conor Dooley <conor.dooley@microchip.com>

Cheers,
Conor.

> ---
> v2: Add dependency check for Sump.
>     Put the check blok after single-letters and before Z*.
> ---
>  .../devicetree/bindings/riscv/extensions.yaml      | 27 ++++++++++++++++++++++
>  1 file changed, 27 insertions(+)
> 
> diff --git a/Documentation/devicetree/bindings/riscv/extensions.yaml b/Documentation/devicetree/bindings/riscv/extensions.yaml
> index c6ec9290fe07..2b0a8a93bb21 100644
> --- a/Documentation/devicetree/bindings/riscv/extensions.yaml
> +++ b/Documentation/devicetree/bindings/riscv/extensions.yaml
> @@ -262,6 +262,23 @@ properties:
>              ratified in RISC-V Profiles Version 1.0, with commit b1d806605f87
>              ("Updated to ratified state.")
>  
> +        - const: supm
> +          description: |
> +            The standard Supm extension for pointer masking support in user
> +            mode (U-mode) as ratified at commit d70011dde6c2 ("Update to
> +            ratified state") of riscv-j-extension.
> +
> +            Supm represents a combination of underlying hardware capability
> +            (Smnpm or Ssnpm), U-mode consumer privilege level, and M/S-mode
> +            software configuration that enables pointer masking for U-mode.
> +
> +            DO NOT include this property in device trees targeting privileged
> +            system software (S-mode or M-mode).
> +
> +            This property is only appropriate in device trees provided to
> +            U-mode software where the next-higher-privilege-mode supports
> +            Smnpm or Ssnpm and enables it for U-mode.
> +
>          - const: svade
>            description: |
>              The standard Svade supervisor-level extension for SW-managed PTE A/D
> @@ -907,6 +924,16 @@ properties:
>          then:
>            contains:
>              const: b
> +      # Supm depends on Smnpm or Ssnpm
> +      - if:
> +          contains:
> +            const: supm
> +        then:
> +          oneOf:
> +            - contains:
> +                const: smnpm
> +            - contains:
> +                const: ssnpm
>        # Za64rs and Ziccrse depend on Zalrsc or A
>        - if:
>            contains:
> 
> -- 
> 2.43.0
> 

[-- Attachment #2: signature.asc --]
[-- Type: application/pgp-signature, Size: 228 bytes --]