On Tue, Mar 3, 2020 at 2:46 PM Ulf Hansson <ulf.hansson@xxxxxxxxxx> wrote:
>
> On Tue, 3 Mar 2020 at 18:02, Rob Herring <robh@xxxxxxxxxx> wrote:
> >
> > On Tue, Mar 03, 2020 at 04:07:45PM +0100, Ulf Hansson wrote:
> > > While converting to the json-schema, let's also take the opportunity to
> > > further specify/clarify some more details about the DT binding.
> > >
> > > For example, let's define the label where to put the states nodes, set a
> > > pattern for nodename of the state nodes and finally add an example.
> > >
> > > Fixes: a3f048b5424e ("dt: psci: Update DT bindings to support hierarchical PSCI states")
> > > Signed-off-by: Ulf Hansson <ulf.hansson@xxxxxxxxxx>
> > > ---
> > > .../devicetree/bindings/arm/psci.yaml | 2 +-
> > > .../bindings/power/domain-idle-state.txt | 33 ---------
> > > .../bindings/power/domain-idle-state.yaml | 67 +++++++++++++++++++
> > > .../bindings/power/power-domain.yaml | 22 +++---
> > > .../bindings/power/power_domain.txt | 2 +-
> > > 5 files changed, 79 insertions(+), 47 deletions(-)
> > > delete mode 100644 Documentation/devicetree/bindings/power/domain-idle-state.txt
> > > create mode 100644 Documentation/devicetree/bindings/power/domain-idle-state.yaml
> > >
> > > diff --git a/Documentation/devicetree/bindings/arm/psci.yaml b/Documentation/devicetree/bindings/arm/psci.yaml
> > > index 540211a080d4..0bc3c43a525a 100644
> > > --- a/Documentation/devicetree/bindings/arm/psci.yaml
> > > +++ b/Documentation/devicetree/bindings/arm/psci.yaml
> > > @@ -123,7 +123,7 @@ properties:
> > > to mandate it.
> > >
> > > [3] Documentation/devicetree/bindings/power/power_domain.txt
> > > - [4] Documentation/devicetree/bindings/power/domain-idle-state.txt
> > > + [4] Documentation/devicetree/bindings/power/domain-idle-state.yaml
> > >
> > > power-domains:
> > > $ref: '/schemas/types.yaml#/definitions/phandle-array'
> > > diff --git a/Documentation/devicetree/bindings/power/domain-idle-state.txt b/Documentation/devicetree/bindings/power/domain-idle-state.txt
> > > deleted file mode 100644
> > > index eefc7ed22ca2..000000000000
> > > --- a/Documentation/devicetree/bindings/power/domain-idle-state.txt
> > > +++ /dev/null
> > > @@ -1,33 +0,0 @@
> > > -PM Domain Idle State Node:
> > > -
> > > -A domain idle state node represents the state parameters that will be used to
> > > -select the state when there are no active components in the domain.
> > > -
> > > -The state node has the following parameters -
> > > -
> > > -- compatible:
> > > - Usage: Required
> > > - Value type: <string>
> > > - Definition: Must be "domain-idle-state".
> > > -
> > > -- entry-latency-us
> > > - Usage: Required
> > > - Value type: <prop-encoded-array>
> > > - Definition: u32 value representing worst case latency in
> > > - microseconds required to enter the idle state.
> > > - The exit-latency-us duration may be guaranteed
> > > - only after entry-latency-us has passed.
> > > -
> > > -- exit-latency-us
> > > - Usage: Required
> > > - Value type: <prop-encoded-array>
> > > - Definition: u32 value representing worst case latency
> > > - in microseconds required to exit the idle state.
> > > -
> > > -- min-residency-us
> > > - Usage: Required
> > > - Value type: <prop-encoded-array>
> > > - Definition: u32 value representing minimum residency duration
> > > - in microseconds after which the idle state will yield
> > > - power benefits after overcoming the overhead in entering
> > > -i the idle state.
> > > diff --git a/Documentation/devicetree/bindings/power/domain-idle-state.yaml b/Documentation/devicetree/bindings/power/domain-idle-state.yaml
> > > new file mode 100644
> > > index 000000000000..27da43076b85
> > > --- /dev/null
> > > +++ b/Documentation/devicetree/bindings/power/domain-idle-state.yaml
> > > @@ -0,0 +1,67 @@
> > > +# SPDX-License-Identifier: GPL-2.0
> > > +%YAML 1.2
> > > +---
> > > +$id: http://devicetree.org/schemas/power/domain-idle-state.yaml#
> > > +$schema: http://devicetree.org/meta-schemas/core.yaml#
> > > +
> > > +title: PM Domain Idle States binding description
> > > +
> > > +maintainers:
> > > + - Ulf Hansson <ulf.hansson@xxxxxxxxxx>
> > > +
> > > +description:
> > > + A domain idle state node represents the state parameters that will be used to
> > > + select the state when there are no active components in the PM domain.
> > > +
> > > +properties:
> > > + $nodename:
> > > + const: domain-idle-states
> > > +
> > > +patternProperties:
> > > + "^(cpu|cluster|domain)-":
> > > + type: object
> > > + description:
> > > + Each state node represents a domain idle state description.
> > > +
> > > + properties:
> > > + compatible:
> > > + const: domain-idle-state
> > > +
> > > + entry-latency-us:
> > > + $ref: /schemas/types.yaml#/definitions/uint32
> >
> > You don't need a type because the core schema defines it for all
> > standard units.
>
> Okay, I noticed some skips this, but wanted rather to clear and fuzzy.
>
> In any case, yes, let's remove it.
>
> >
> > > + description:
> > > + The worst case latency in microseconds required to enter the idle
> > > + state. Note that, the exit-latency-us duration may be guaranteed only
> > > + after the entry-latency-us has passed.
> > > +
> > > + exit-latency-us:
> > > + $ref: /schemas/types.yaml#/definitions/uint32
> > > + description:
> > > + The worst case latency in microseconds required to exit the idle
> > > + state.
> > > +
> > > + min-residency-us:
> > > + $ref: /schemas/types.yaml#/definitions/uint32
> > > + description:
> > > + The minimum residency duration in microseconds after which the idle
> > > + state will yield power benefits, after overcoming the overhead while
> > > + entering the idle state.
> > > +
> > > + required:
> > > + - compatible
> > > + - entry-latency-us
> > > + - exit-latency-us
> > > + - min-residency-us
> >
> > additionalProperties: false
> >
> > Do we have cases of adding additional properties?
>
> I might, but I am not sure what's the correct way to deal with that.
I was thinking more like a vendor adding properties. Is this a base
class that can be extended or every possible property is defined here.
Actually, with the matching on $nodename, we have to put any additions
in here or do a custom 'select'. In any case, I think we can cross
than when/if we get there.
> What I am wondering about is the "arm,psci-suspend-param" property,
> currently defined as part of the PSCI bindings (psci.yaml).
>
> I am not sure that's correct to define it as a PSCI binding. Shouldn't
> it rather be a part of the idle state bindings (idle-states.yaml) and
> the domain idle states binding ($subject patch)?
Indeed it should be moved here.
>
> What do you think?
>
> In any case, we probably want to fix this on top, if we should care.
Yes, that's fine.
Rob
