[PATCH 02/14] dt/bindings: update binding for PM domain idle states
From: mark.rutland@arm.com (Mark Rutland)
Date: 2016-06-23 17:35:17
Also in:
linux-arm-msm, linux-devicetree, linux-pm
Possibly related (same subject, not in this thread)
- 2016-06-23 · Re: [PATCH 02/14] dt/bindings: update binding for PM domain idle states · Lina Iyer <hidden>
- 2016-06-23 · Re: [PATCH 02/14] dt/bindings: update binding for PM domain idle states · Mark Rutland <hidden>
- 2016-06-22 · [PATCH 02/14] dt/bindings: update binding for PM domain idle states · Lina Iyer <hidden>
Hi, On Wed, Jun 22, 2016 at 01:36:37PM -0600, Lina Iyer wrote:
quoted hunk
From: Axel Haslam <redacted> Update DT bindings to describe idle states of PM domains. Cc: <redacted> Signed-off-by: Marc Titinger <redacted> Signed-off-by: Lina Iyer <redacted> [Lina: Added state properties, removed state names, wakeup-latency, added of_pm_genpd_init() API, pruned commit text] Signed-off-by: Ulf Hansson <redacted> [Ulf: Moved around code to make it compile properly, rebased on top of multiple state support] --- .../devicetree/bindings/power/power_domain.txt | 70 ++++++++++++++++++++++ 1 file changed, 70 insertions(+)diff --git a/Documentation/devicetree/bindings/power/power_domain.txt b/Documentation/devicetree/bindings/power/power_domain.txt index 025b5e7..41e8dda 100644 --- a/Documentation/devicetree/bindings/power/power_domain.txt +++ b/Documentation/devicetree/bindings/power/power_domain.txt@@ -29,6 +29,43 @@ Optional properties: specified by this binding. More details about power domain specifier are available in the next section. +- power-states : A phandle of an idle-state that shall be soaked into a + generic domain power state.
It's somewhat unfortunate that this gives us two possible locations for idle state lists (under the /cpus node and in a pm-domains node), especially as it's not clear what would happen were a DT to have both. I would prefer that we extend the existing bindings such that states can refer to the power domains which they affect.
+==Power state== + +A PM domain power state describes an idle state of a domain and must be +have the following properties - + + - entry-latency-us + Usage: Not required if wakeup-latency-us is provided. + 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: Not required if wakeup-latency-us is provided. + Value type: <prop-encoded-array> + Definition: u32 value representing worst case latency + in microseconds required to exit the idle state.
These are part of the existing idle state binding (Documentation/devicetree/bindings/arm/idle-states.txt), and I would prefer that we did not duplicate this nor come up with an independent set of idle state bindings.
+ + - residency-us: + Usage: Optional + Value type: <prop-encoded-array> + Definition: A u32 value representing the time for which a + domain must be idle in the state to reap power saving benefits + of entering the state.
This is "min-residency-us" per the existing bindings.
+ + - state-param: + Usage: Optional + Value type: <prop-encoded-array> + Definition: A u32 value as defined by the state. May be used + by the driver to hold state related u32 data. In the case of + PSCI, an extended state-id for the domain may be encoded in + this value.
This is "arm,psci-suspend-param", per the existing bindings. Thanks, Mark.