Re: [PATCH v2 3/4] dt-bindings: firmware: scm: add sdm670 compatible

[Konrad Dybcio <konrad.dybcio@somainline.org>]

On 04/11/2022 00:03, Richard Acayan wrote:
> The Snapdragon 670 uses SCM as for PSCI power management. Document the
> appropriate compatible string for it.

SCM and SMC (and SMCCC) are closely related but not the same.


SMC (secure monitor call) is the standard mechanism of invoking 
communication

with TZ.


SCM (secure channel manager) is a QC mechanism of communicating with their

vast vast vast HYP and TZ implementations, using HVC (hypervisor call) 
and SMC

respectively.


SMCCC (secure monitor call calling convention) is a standard for how to 
structure

SMCs and HVCs.


PSCI uses SMC calls on sdm670.


Konrad

>
> Signed-off-by: Richard Acayan <mailingradian@gmail.com>
> Acked-by: Rob Herring <robh@kernel.org>
> Reviewed-by: Guru Das Srinagesh <quic_gurus@quicinc.com>
> ---
>   Documentation/devicetree/bindings/firmware/qcom,scm.yaml | 1 +
>   1 file changed, 1 insertion(+)
>
> diff --git a/Documentation/devicetree/bindings/firmware/qcom,scm.yaml b/Documentation/devicetree/bindings/firmware/qcom,scm.yaml
> index be1b5746eddb..25688571ee7c 100644
> --- a/Documentation/devicetree/bindings/firmware/qcom,scm.yaml
> +++ b/Documentation/devicetree/bindings/firmware/qcom,scm.yaml
> @@ -41,6 +41,7 @@ properties:
>             - qcom,scm-sc7180
>             - qcom,scm-sc7280
>             - qcom,scm-sc8280xp
> +          - qcom,scm-sdm670
>             - qcom,scm-sdm845
>             - qcom,scm-sdx55
>             - qcom,scm-sdx65