[PATCH v2 2/3] Documentation: devicetree: Add new binding for PSCIv0.2

[Rob Herring]

On Thu, Mar 27, 2014 at 10:38 AM, Ashwin Chaugule
<ashwin.chaugule at linaro.org> wrote:
> The PSCI v0.2+ spec defines standard values for PSCI function IDs.
> Add a new binding entry so that pre v0.2 implementations can
> use DT entries for function IDs and v0.2+ implementations use
> standard entries as defined by the PSCIv0.2 specification.
>
> Signed-off-by: Ashwin Chaugule <ashwin.chaugule at linaro.org>

Acked-by: Rob Herring <robh at kernel.org>

> ---
>  Documentation/devicetree/bindings/arm/psci.txt | 35 +++++++++++++++++++++++++-
>  1 file changed, 34 insertions(+), 1 deletion(-)
>
> diff --git a/Documentation/devicetree/bindings/arm/psci.txt b/Documentation/devicetree/bindings/arm/psci.txt
> index 433afe9..d01a90b 100644
> --- a/Documentation/devicetree/bindings/arm/psci.txt
> +++ b/Documentation/devicetree/bindings/arm/psci.txt
> @@ -21,7 +21,15 @@ to #0.
>
>  Main node required properties:
>
> - - compatible    : Must be "arm,psci"
> + - compatible    : should contain at least one of:
> +
> +                                * "arm,psci" : for implementations complying to PSCI versions prior to
> +                                       0.2. For these cases function IDs must be provided.
> +
> +                                * "arm,psci-0.2" : for implementations complying to PSCI 0.2. Function
> +                                       IDs are not required and should be ignored by an OS with PSCI 0.2
> +                                       support, but are permitted to be present for compatibility with
> +                                       existing software when "arm,psci" is later in the compatible list.
>
>   - method        : The method of calling the PSCI firmware. Permitted
>                     values are:
> @@ -45,6 +53,8 @@ Main node optional properties:
>
>  Example:
>
> +Case 1: PSCI v0.1 only.
> +
>         psci {
>                 compatible      = "arm,psci";
>                 method          = "smc";
> @@ -53,3 +63,26 @@ Example:
>                 cpu_on          = <0x95c10002>;
>                 migrate         = <0x95c10003>;
>         };
> +
> +
> +Case 2: PSCI v0.2 only
> +
> +       psci {
> +               compatible      = "arm,psci-0.2";
> +               method          = "smc";
> +       };
> +
> +Case 3: PSCI v0.2 and PSCI v0.1.
> +
> +       As described above, for compatibility with existing kernels, the
> +       hypervisor will likely want to provide IDs, e.g.
> +
> +       psci {
> +               compatible = "arm,psci-0.2", "arm,psci";
> +               method = "hvc";
> +
> +               cpu_on = < arbitrary value >;
> +               cpu_off = < arbitrary value >;
> +
> +               ...
> +       };
> --
> 1.8.3.2
>