On 27-02-17, 18:31, Rob Herring wrote:
> 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.ku...@linaro.org>
> > Tested-by: Rajendra Nayak <rna...@codeaurora.org>
> > ---
> > .../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>".
Wow, even the examples in the OPP document have these screwed up :(
> With that fixed,
>
> Acked-by: Rob Herring <r...@kernel.org>
Thanks.
--
viresh
