The System Control Processor (SCP) provides access to SoC sensors via the System Control and Power Interface (SCPI) Message Protocol. Add bindings to allow probing of these sensors. Also support referencing of the sensors for setting up thermal zones via the thermal DT bindings. Signed-off-by: Punit Agrawal <punit.agrawal@xxxxxxx> Cc: Rob Herring <robh+dt@xxxxxxxxxx> Cc: Mark Rutland <mark.rutland@xxxxxxx> Cc: Sudeep Holla <sudeep.holla@xxxxxxx> --- Documentation/devicetree/bindings/arm/arm,scpi.txt | 38 ++++++++++++++++++++++ 1 file changed, 38 insertions(+) diff --git a/Documentation/devicetree/bindings/arm/arm,scpi.txt b/Documentation/devicetree/bindings/arm/arm,scpi.txt index f002460..86302de 100644 --- a/Documentation/devicetree/bindings/arm/arm,scpi.txt +++ b/Documentation/devicetree/bindings/arm/arm,scpi.txt @@ -72,8 +72,25 @@ Required sub-node properties: - compatible : should be "arm,juno-scp-shmem" for Non-secure SRAM based shared memory on Juno platforms +Sensor bindings for the sensors based on SCPI Message Protocol +-------------------------------------------------------------- +SCPI provides an API to access the various sensors on the SoC. + +Required properties: +- compatible : should be "arm,scpi-sensors". +- #thermal-sensor-cells: should be set to 1. This property follows the + thermal device tree bindings[2]. + + Valid cell values are raw identifiers (Sensor + ID) as used by the firmware. Refer to + platform documentation for your + implementation for the IDs to use. For Juno + R0 and Juno R1 refer to [3]. + [0] http://infocenter.arm.com/help/topic/com.arm.doc.dui0922b/index.html [1] Documentation/devicetree/bindings/clock/clock-bindings.txt +[2] Documentation/devicetree/bindings/thermal/thermal.txt +[3] http://infocenter.arm.com/help/index.jsp?topic=/com.arm.doc.dui0922b/apas03s22.html Example: @@ -122,6 +139,11 @@ scpi_protocol: scpi@2e000000 { clock-output-names = "pxlclk0", "pxlclk1"; }; }; + + scpi_sensors0: sensors { + compatible = "arm,scpi-sensors"; + #thermal-sensor-cells = <1>; + }; }; cpu@0 { @@ -136,6 +158,17 @@ hdlcd@7ff60000 { clocks = <&scpi_clk 4>; }; +thermal-zones { + soc_thermal { + polling-delay-passive = <100>; + polling-delay = <1000>; + + /* sensor ID */ + thermal-sensors = <&scpi_sensors0 3>; + ... + }; +}; + In the above example, the #clock-cells is set to 1 as required. scpi_dvfs has 3 output clocks namely: atlclk, aplclk, and gpuclk with 0, 1 and 2 as clock-indices. scpi_clk has 2 output clocks namely: pxlclk0 @@ -148,3 +181,8 @@ scpi_dvfs i.e. "atlclk". Similarly the second example is hdlcd@7ff60000 and it has pxlclk1 as input clock. '4' in the clock specifier here points to the second entry in the output clocks of scpi_clocks i.e. "pxlclk1" + +The thermal-sensors property in the soc_thermal node uses the +temperature sensor provided by SCP firmware to setup a thermal +zone. The ID "3" is the sensor identifier for the temperature sensor +as used by the firmware. -- 2.5.1 -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
