Re: [PATCH v4 3/4] dt-bindings: arm: Add new compatible for smc/hvc transport for SCMI

Sudeep Holla
2023-10-03T10:44:10Z

On Mon, Sep 11, 2023 at 12:43:58PM -0700, Nikunj Kela wrote:
> Introduce compatible "qcom,scmi-hvc-shmem" for SCMI smc/hvc
> transport channel for Qualcomm virtual platforms.
> The compatible mandates a shared memory channel.
>
> Signed-off-by: Nikunj Kela <quic_nkela@quicinc.com>
> Acked-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
> ---
> .../devicetree/bindings/firmware/arm,scmi.yaml | 12 ++++++++++++
> 1 file changed, 12 insertions(+)
>
> diff --git a/Documentation/devicetree/bindings/firmware/arm,scmi.yaml b/Documentation/devicetree/bindings/firmware/arm,scmi.yaml
> index 8d54ea768d38..4090240f45b1 100644
> --- a/Documentation/devicetree/bindings/firmware/arm,scmi.yaml
> +++ b/Documentation/devicetree/bindings/firmware/arm,scmi.yaml
> @@ -45,6 +45,9 @@ properties:
> - description: SCMI compliant firmware with OP-TEE transport
> items:
> - const: linaro,scmi-optee
> + - description: SCMI compliant firmware with Qualcomm hvc/shmem transport
> + items:
> + - const: qcom,scmi-hvc-shmem

Can it be simply "qcom,scmi-smc" for 2 reasons ?
1. We don't support SMC/HVC without shmem, so what is your argument to add
'-shmem' in the compatible here ?
2. The exact conduit(SMC/HVC) used is detected runtime, so I prefer to keep
'-smc' instead of '-hvc' in the compatible just to avoid giving an illusion
that HVC is the conduit chosen here based on the compatible. It can be true
for other reason but I don't want to mislead here by using HVC.
>
> interrupts:
> description:
> @@ -320,6 +323,15 @@ allOf:
> required:
> - linaro,optee-channel-id
>
> + - if:
> + properties:
> + compatible:
> + contains:
> + const: qcom,scmi-hvc-shmem
> + then:
> + required:
> + - shmem
> +
> examples:
> - |
> firmware {
> --
> 2.17.1
>

--
Regards,
Sudeep