summaryrefslogtreecommitdiffstats
path: root/dts/Bindings/arm/psci.txt
diff options
context:
space:
mode:
Diffstat (limited to 'dts/Bindings/arm/psci.txt')
-rw-r--r--dts/Bindings/arm/psci.txt111
1 files changed, 0 insertions, 111 deletions
diff --git a/dts/Bindings/arm/psci.txt b/dts/Bindings/arm/psci.txt
deleted file mode 100644
index a2c4f1d524..0000000000
--- a/dts/Bindings/arm/psci.txt
+++ /dev/null
@@ -1,111 +0,0 @@
-* 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 : should contain at least one of:
-
- * "arm,psci" : For implementations complying to PSCI versions prior
- to 0.2.
- For these cases function IDs must be provided.
-
- * "arm,psci-0.2" : For implementations complying to PSCI 0.2.
- Function IDs are not required and should be ignored by
- an OS with PSCI 0.2 support, but are permitted to be
- present for compatibility with existing software when
- "arm,psci" is later in the compatible list.
-
- * "arm,psci-1.0" : For implementations complying to PSCI 1.0.
- PSCI 1.0 is backward compatible with PSCI 0.2 with
- minor specification updates, as defined in the PSCI
- specification[2].
-
- - 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
-
-Device tree nodes that require usage of PSCI CPU_SUSPEND function (ie idle
-state nodes, as per bindings in [1]) must specify the following properties:
-
-- arm,psci-suspend-param
- Usage: Required for state nodes[1] if the corresponding
- idle-states node entry-method property is set
- to "psci".
- Value type: <u32>
- Definition: power_state parameter to pass to the PSCI
- suspend call.
-
-Example:
-
-Case 1: PSCI v0.1 only.
-
- psci {
- compatible = "arm,psci";
- method = "smc";
- cpu_suspend = <0x95c10000>;
- cpu_off = <0x95c10001>;
- cpu_on = <0x95c10002>;
- migrate = <0x95c10003>;
- };
-
-Case 2: PSCI v0.2 only
-
- psci {
- compatible = "arm,psci-0.2";
- method = "smc";
- };
-
-Case 3: PSCI v0.2 and PSCI v0.1.
-
- A DTB may provide IDs for use by kernels without PSCI 0.2 support,
- enabling firmware and hypervisors to support existing and new kernels.
- These IDs will be ignored by kernels with PSCI 0.2 support, which will
- use the standard PSCI 0.2 IDs exclusively.
-
- psci {
- compatible = "arm,psci-0.2", "arm,psci";
- method = "hvc";
-
- cpu_on = < arbitrary value >;
- cpu_off = < arbitrary value >;
-
- ...
- };
-
-[1] Kernel documentation - ARM idle states bindings
- Documentation/devicetree/bindings/arm/idle-states.txt
-[2] Power State Coordination Interface (PSCI) specification
- http://infocenter.arm.com/help/topic/com.arm.doc.den0022c/DEN0022C_Power_State_Coordination_Interface.pdf