Will Deacon
2012-Dec-18 17:53 UTC
[PATCH v3 3/6] ARM: psci: add devicetree binding for describing PSCI firmware
This patch adds a new devicetree binding for describing PSCI firmware
to Linux.
Signed-off-by: Will Deacon <will.deacon@arm.com>
---
Documentation/devicetree/bindings/arm/psci.txt | 55 ++++++++++++++++++++++++++
1 file changed, 55 insertions(+)
create mode 100644 Documentation/devicetree/bindings/arm/psci.txt
diff --git a/Documentation/devicetree/bindings/arm/psci.txt
b/Documentation/devicetree/bindings/arm/psci.txt
new file mode 100644
index 0000000..433afe9
--- /dev/null
+++ b/Documentation/devicetree/bindings/arm/psci.txt
@@ -0,0 +1,55 @@
+* Power State Coordination Interface (PSCI)
+
+Firmware implementing the PSCI functions described in ARM document number
+ARM DEN 0022A ("Power State Coordination Interface System Software on ARM
+processors") can be used by Linux to initiate various CPU-centric power
+operations.
+
+Issue A of the specification describes functions for CPU suspend, hotplug
+and migration of secure software.
+
+Functions are invoked by trapping to the privilege level of the PSCI
+firmware (specified as part of the binding below) and passing arguments
+in a manner similar to that specified by AAPCS:
+
+ r0 => 32-bit Function ID / return value
+ {r1 - r3} => Parameters
+
+Note that the immediate field of the trapping instruction must be set
+to #0.
+
+
+Main node required properties:
+
+ - compatible : Must be "arm,psci"
+
+ - method : The method of calling the PSCI firmware. Permitted
+ values are:
+
+ "smc" : SMC #0, with the register assignments
specified
+ in this binding.
+
+ "hvc" : HVC #0, with the register assignments
specified
+ in this binding.
+
+Main node optional properties:
+
+ - cpu_suspend : Function ID for CPU_SUSPEND operation
+
+ - cpu_off : Function ID for CPU_OFF operation
+
+ - cpu_on : Function ID for CPU_ON operation
+
+ - migrate : Function ID for MIGRATE operation
+
+
+Example:
+
+ psci {
+ compatible = "arm,psci";
+ method = "smc";
+ cpu_suspend = <0x95c10000>;
+ cpu_off = <0x95c10001>;
+ cpu_on = <0x95c10002>;
+ migrate = <0x95c10003>;
+ };
--
1.8.0
Nicolas Pitre
2012-Dec-19 04:11 UTC
Re: [PATCH v3 3/6] ARM: psci: add devicetree binding for describing PSCI firmware
On Tue, 18 Dec 2012, Will Deacon wrote:> This patch adds a new devicetree binding for describing PSCI firmware > to Linux. > > Signed-off-by: Will Deacon <will.deacon@arm.com>Acked-by: Nicolas Pitre <nico@linaro.org>> --- > Documentation/devicetree/bindings/arm/psci.txt | 55 ++++++++++++++++++++++++++ > 1 file changed, 55 insertions(+) > create mode 100644 Documentation/devicetree/bindings/arm/psci.txt > > diff --git a/Documentation/devicetree/bindings/arm/psci.txt b/Documentation/devicetree/bindings/arm/psci.txt > new file mode 100644 > index 0000000..433afe9 > --- /dev/null > +++ b/Documentation/devicetree/bindings/arm/psci.txt > @@ -0,0 +1,55 @@ > +* Power State Coordination Interface (PSCI) > + > +Firmware implementing the PSCI functions described in ARM document number > +ARM DEN 0022A ("Power State Coordination Interface System Software on ARM > +processors") can be used by Linux to initiate various CPU-centric power > +operations. > + > +Issue A of the specification describes functions for CPU suspend, hotplug > +and migration of secure software. > + > +Functions are invoked by trapping to the privilege level of the PSCI > +firmware (specified as part of the binding below) and passing arguments > +in a manner similar to that specified by AAPCS: > + > + r0 => 32-bit Function ID / return value > + {r1 - r3} => Parameters > + > +Note that the immediate field of the trapping instruction must be set > +to #0. > + > + > +Main node required properties: > + > + - compatible : Must be "arm,psci" > + > + - method : The method of calling the PSCI firmware. Permitted > + values are: > + > + "smc" : SMC #0, with the register assignments specified > + in this binding. > + > + "hvc" : HVC #0, with the register assignments specified > + in this binding. > + > +Main node optional properties: > + > + - cpu_suspend : Function ID for CPU_SUSPEND operation > + > + - cpu_off : Function ID for CPU_OFF operation > + > + - cpu_on : Function ID for CPU_ON operation > + > + - migrate : Function ID for MIGRATE operation > + > + > +Example: > + > + psci { > + compatible = "arm,psci"; > + method = "smc"; > + cpu_suspend = <0x95c10000>; > + cpu_off = <0x95c10001>; > + cpu_on = <0x95c10002>; > + migrate = <0x95c10003>; > + }; > -- > 1.8.0 >