Re: [PATCH v3 1/3] dt-bindings: riscv: clarify Svadu boot-time behavior

[Conor Dooley <conor@kernel.org>]

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On Tue, Jun 09, 2026 at 09:00:18PM +0800, Yunhui Cui wrote:
> Clarify that systems which advertise only Svadu have hardware PTE A/D
> updating enabled at boot, while systems advertising both Svade and Svadu
> must enable Svadu explicitly with SBI FWFT.
> 
> Signed-off-by: Yunhui Cui <cuiyunhui@bytedance.com>
> Reviewed-by: Qingwei Hu <qingwei.hu@bytedance.com>
> ---
>  Documentation/devicetree/bindings/riscv/extensions.yaml | 6 +++---
>  1 file changed, 3 insertions(+), 3 deletions(-)
> 
> diff --git a/Documentation/devicetree/bindings/riscv/extensions.yaml b/Documentation/devicetree/bindings/riscv/extensions.yaml
> index 2b0a8a93bb214..b09888e9988de 100644
> --- a/Documentation/devicetree/bindings/riscv/extensions.yaml
> +++ b/Documentation/devicetree/bindings/riscv/extensions.yaml
> @@ -294,10 +294,10 @@ properties:
>                 of the PTE A/D bits or page faults when they need updated.
>              2) Only Svade present in DT => Supervisor must assume Svade to be
>                 always enabled.
> -            3) Only Svadu present in DT => Supervisor must assume Svadu to be
> -               always enabled.
> +            3) Only Svadu present in DT => Supervisor must assume Svadu is
> +               enabled at boot.

Commit message is missing an explanation of why this behaviour change is
not problematic. Although, to be honest, I am not sure what the changed text
actually means. If only Svadu is present, then the hardware doesn't support
Svade, and therefore Svadu would never be anything other than enabled so
changing the wording to specify "at boot" seems less clear?

>              4) Both Svade and Svadu present in DT => Supervisor must assume
> -               Svadu turned-off at boot time. To use Svadu, supervisor must
> +               Svadu is disabled at boot time. To use Svadu, supervisor must

This change doesn't actually do anything, "turned-off" and "disabled"
are the same thing - although the latter is more desirable wording I
think. I have no problems with this portion of the patch.

>                 explicitly enable it using the SBI FWFT extension.
>  
>          - const: svadu
> -- 
> 2.39.5
> 

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