From 00ce25c6dcdae5582ae4be37147ab33678adc995 Mon Sep 17 00:00:00 2001 From: Sascha Hauer Date: Fri, 25 Apr 2014 11:22:32 +0200 Subject: Add devicetree source files as of Linux-3.15-rc2 This adds the Linux dts files to barebox. The dts files are generated from Ian Campbells device-tree-rebasing.git: git://xenbits.xen.org/people/ianc/device-tree-rebasing.git The dts are found in dts/ in the barebox repository and will be updated from upstream regularly, probably for each upstream -rc. To keep the synchronization with upstream easy no changes to the original files are allowed under dts/. Instead changes to upstream dts files will be done using overlays in arch/$ARCH/dts/. Signed-off-by: Sascha Hauer --- dts/Bindings/arm/psci.txt | 55 +++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 55 insertions(+) create mode 100644 dts/Bindings/arm/psci.txt (limited to 'dts/Bindings/arm/psci.txt') diff --git a/dts/Bindings/arm/psci.txt b/dts/Bindings/arm/psci.txt new file mode 100644 index 0000000000..433afe9cb5 --- /dev/null +++ b/dts/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>; + }; -- cgit v1.2.3