lkml.org 
[lkml]   [2015]   [Sep]   [22]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    /
    From
    SubjectRe: [PATCH v4 1/5] Documentation: add DT bindings for ARM SCPI sensors
    Date
    Punit Agrawal <punit.agrawal@arm.com> writes:

    > 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@arm.com>
    > Cc: Rob Herring <robh+dt@kernel.org>
    > Cc: Mark Rutland <mark.rutland@arm.com>
    > Cc: Sudeep Holla <sudeep.holla@arm.com>

    Gentle reminder for review of the below bindings. They've been updated
    based on feedback on the earlier version [a].

    If there are no further comments, I'd like to request an ack from the DT
    reviewers.

    [a] http://thread.gmane.org/gmane.linux.power-management.general/65475/focus=134976

    > ---
    > 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.


    \
     
     \ /
      Last update: 2015-09-22 16:41    [W:4.187 / U:0.808 seconds]
    ©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site