On Fri, Feb 24, 2017 at 02:36:33PM +0530, Viresh Kumar wrote:
> Some platforms have the capability to configure the performance state of
> their power domains. The process of configuring the performance state is
> pretty much platform dependent and we may need to work with a wide range
> of configurables. For some platforms, like Qcom, it can be a positive
> integer value alone, while in other cases it can be voltage levels, etc.
>
> The power-domain framework until now was only designed for the idle
> state management of the device and this needs to change in order to
> reuse the power-domain framework for active state management of the
> devices.
>
> This patch adds DT bindings to describe the performance states of a
> power domain. The power domain node needs to contain a
> "performance-states" node, which itself is an array of per-state nodes.
> Each per-state node represents individual performance state of a device.
> Individual nodes are identified by their (mandatory) "reg" field. These
> nodes can also contain an optional "domain-microvolt" property. More
> properties can be added later on once we have more platforms using it.
>
> If the consumers don't need the capability of switching to different
> domain performance states at runtime, then they can simply define their
> required domain performance state in their node directly using the
> "domain-performance-state" property. Otherwise the consumers can define
> their requirements with help of other infrastructure, for example the
> OPP table (added in a later commit).
>
> Signed-off-by: Viresh Kumar <viresh.kumar@xxxxxxxxxx>
> Tested-by: Rajendra Nayak <rnayak@xxxxxxxxxxxxxx>
> ---
> .../devicetree/bindings/power/power_domain.txt | 67 ++++++++++++++++++++++
> 1 file changed, 67 insertions(+)
>
> diff --git a/Documentation/devicetree/bindings/power/power_domain.txt b/Documentation/devicetree/bindings/power/power_domain.txt
> index 723e1ad937da..9be09e576f68 100644
> --- a/Documentation/devicetree/bindings/power/power_domain.txt
> +++ b/Documentation/devicetree/bindings/power/power_domain.txt
> @@ -38,6 +38,33 @@ 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.
>
> +- performance-states : This describes the performance states of a PM domain.
> + The performance-states node reflects the performance states of this PM domain
> + and not the performance states of the devices or sub-domains in the PM domain.
> + Sub domains can have their own performance states. Sub domains without their
> + own performance states are governed by the performance states of the parent
> + domain and the "domain-performance-state" properties of their consumers refer
> + to the "reg" properties of the nodes in the parent domain.
> +
> + Required properties of the performance-states node:
> + - compatible: Allow performance states to express their compatibility. It
> + should be: "domain-performance-state".
> +
> + - nodes: The performance-states node should contain one or
> + more nodes, each representing a supported performance state.
> +
> + Required properties of the performance state nodes:
> + - reg: A positive integer value representing the performance level
> + associated with a performance state. The integer value '0' represents the
> + lowest performance level and the highest value represents the highest
> + performance level. The exact meaning and performance implications of
> + individual values is left to be defined by the user platform.
> +
> + Optional properties of performance state nodes:
> + - domain-microvolt: voltage in micro Volts. A single regulator's voltage is
> + specified with an array of size one or three. Single entry is for target
> + voltage and three entries are for <target min max> voltages.
> +
> Example:
>
> power: power-controller@12340000 {
> @@ -118,4 +145,44 @@ 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
> + performance level (of the parent domain) required by the consumer for its
> + working. The integer value '0' represents the lowest performance level and the
> + highest value represents the highest performance level. The value of
> + domain-performance-state field should match one of the "reg" fields in the
> + "performance-states" table of the parent power domain.
> +
> +
> +Example:
> +
> + parent: power-controller@12340000 {
> + compatible = "foo,power-controller";
> + reg = <0x12340000 0x1000>;
> + #power-domain-cells = <0>;
> +
> + performance-states {
> + compatible = "domain-performance-state";
> + pstate@1 {
> + reg = <1>;
> + domain-microvolt = <970000 975000 985000>;
This doesn't look like "<target> <min> <max>".
With that fixed,
Acked-by: Rob Herring <robh@xxxxxxxxxx>
> + };
> + pstate@2 {
> + reg = <2>;
> + domain-microvolt = <1000000 1075000 1085000>;
> + };
> + pstate@3 {
> + reg = <3>;
> + domain-microvolt = <1100000 1175000 1185000>;
> + };
> + };
> + };
> +
> + leaky-device@12350000 {
> + compatible = "foo,i-leak-current";
> + reg = <0x12350000 0x1000>;
> + power-domains = <&power 0>;
> + domain-performance-state = <2>;
> + };
> +
> [1]. Documentation/devicetree/bindings/power/domain-idle-state.txt
> --
> 2.7.1.410.g6faf27b
>
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