Re: [PATCH v2 1/6] dt-bindings: gpu: nvidia,gk20a: Require the fuse clock

[Rob Herring <robh@kernel.org>]

On Fri, Oct 16, 2026 at 12:06:54PM -0400, Sasha Levin wrote:
> The GM20B on Tegra210 often fails to initialize unless the fuse clock
> is running while the GPU is powered, and the GPUs on the other Tegra
> generations are expected to have the same requirement. Tegra194 already
> describes the fuse clock for its GV11B.
> 
> Make the fuse clock required for all of them, and list the exact clocks
> for each GPU instead of allowing either the reference or the fuse clock
> as the third one: GM20B takes the fuse clock after its reference clock,
> the others take it after the GPU and power clocks.
> 
> The nouveau driver keeps treating the fuse clock as optional, so device
> trees that lack it continue to work as before.
> 
> Assisted-by: LLM
> Signed-off-by: Sasha Levin <sashal@kernel.org>
> ---
>  .../devicetree/bindings/gpu/nvidia,gk20a.yaml | 52 ++++++++++++++-----
>  1 file changed, 40 insertions(+), 12 deletions(-)
> 
> diff --git a/Documentation/devicetree/bindings/gpu/nvidia,gk20a.yaml b/Documentation/devicetree/bindings/gpu/nvidia,gk20a.yaml
> index 4d856a8b674c5..af0ada6e02557 100644
> --- a/Documentation/devicetree/bindings/gpu/nvidia,gk20a.yaml
> +++ b/Documentation/devicetree/bindings/gpu/nvidia,gk20a.yaml
> @@ -39,18 +39,12 @@ properties:
>        Regulator for GPU supply voltage
>  
>    clocks:
> -    minItems: 2
> -    items:
> -      - description: GPU clock
> -      - description: Power clock
> -      - description: Reference or fuse clock
> +    minItems: 3
> +    maxItems: 4
>  
>    clock-names:
> -    minItems: 2
> -    items:
> -      - const: gpu
> -      - const: pwr
> -      - enum: [ ref, fuse ]
> +    minItems: 3
> +    maxItems: 4

See my reply on v1. We want to keep the names defined at the top-level 
(to avoid ever variant making up their own names).

Rob