Re: [PATCH V4 2/9] PM / Domains: Use OPP tables for power-domains

From: Sudeep Holla
Date: Wed Apr 12 2017 - 12:59:21 EST




On 20/03/17 09:32, Viresh Kumar wrote:
> The OPP table bindings contains all the necessary fields to support
> power-domains now. Update the power-domain bindings to allow
> "operating-points-v2" to be present within the power-domain node.
>
> Also allow consumer devices, that don't use OPP tables, to specify the
> parent power-domain's performance level using the
> "domain-performance-state" property.
>
> Signed-off-by: Viresh Kumar <viresh.kumar@xxxxxxxxxx>
> ---
> .../devicetree/bindings/power/power_domain.txt | 42 ++++++++++++++++++++++
> 1 file changed, 42 insertions(+)
>
> diff --git a/Documentation/devicetree/bindings/power/power_domain.txt b/Documentation/devicetree/bindings/power/power_domain.txt
> index 723e1ad937da..5db112fa5d7c 100644
> --- a/Documentation/devicetree/bindings/power/power_domain.txt
> +++ b/Documentation/devicetree/bindings/power/power_domain.txt
> @@ -38,6 +38,9 @@ phandle arguments (so called PM domain specifiers) of length specified by the
> domain's idle states. In the absence of this property, the domain would be
> considered as capable of being powered-on or powered-off.
>
> +- operating-points-v2 : This describes the performance states of a PM domain.
> + Refer to ../opp/opp.txt for more information.
> +
> Example:
>
> power: power-controller@12340000 {
> @@ -118,4 +121,43 @@ The node above defines a typical PM domain consumer device, which is located
> inside a PM domain with index 0 of a power controller represented by a node
> with the label "power".
>
> +Optional properties:
> +- domain-performance-state: A positive integer value representing the minimum
> + power-domain performance level required by the consumer device. The integer
> + value '0' represents the lowest performance level and the higher values
> + represent higher performance levels. The value of "domain-performance-state"
> + field should match the "domain-performance-state" field of one of the OPP
> + nodes in the parent power-domain's OPP table.
> +
> +
> +
> +Example:
> +
> + domain_opp_table: opp_table {
> + compatible = "operating-points-v2";
> +
> + opp@1 {
> + domain-performance-state = <1>;
> + opp-microvolt = <975000 970000 985000>;
> + };
> + opp@2 {
> + domain-performance-state = <2>;
> + opp-microvolt = <1075000 1000000 1085000>;
> + };
> + };
> +
> + parent: power-controller@12340000 {
> + compatible = "foo,power-controller";
> + reg = <0x12340000 0x1000>;
> + #power-domain-cells = <0>;
> + operating-points-v2 = <&domain_opp_table>;

As mentioned in the other email, it would be good to consider
scalability with multiple power domains in a PM domain provider.
i.e case of #power-domain-cells = <1> or more

--
Regards,
Sudeep