Add device binding documentation for Qualcomm Technology Inc's PDC timer. The driver is used for programming next wake-up timer value when processor enters SoC level deepest low power state. Cc: devicetree@xxxxxxxxxxxxxxx Signed-off-by: Raju P.L.S.S.S.N <rplsssn@xxxxxxxxxxxxxx> --- .../devicetree/bindings/soc/qcom/rpmh-rsc.txt | 29 +++++++++++++++++++ 1 file changed, 29 insertions(+) diff --git a/Documentation/devicetree/bindings/soc/qcom/rpmh-rsc.txt b/Documentation/devicetree/bindings/soc/qcom/rpmh-rsc.txt index 9b86d1eff219..f24afb45d0d9 100644 --- a/Documentation/devicetree/bindings/soc/qcom/rpmh-rsc.txt +++ b/Documentation/devicetree/bindings/soc/qcom/rpmh-rsc.txt @@ -30,6 +30,12 @@ will be an aggregate of the sleep votes from each of those subsystems. Clients may request a sleep value for their shared resources in addition to the active mode requests. +When the processor enters deepest low power mode, the next wake-up timer value +needs to be programmed to PDC (Power Domain Controller) through RSC registers +dedicated for this purpose. PDC timer is specified as child node of RSC with +register offets to program timer match value. + + Properties: - compatible: @@ -86,6 +92,20 @@ Properties: Drivers that want to use the RSC to communicate with RPMH must specify their bindings as child nodes of the RSC controllers they wish to communicate with. +If an RSC needs to program next wake-up in the PDC timer, it must specify the +binding as child node with the following properties: + +Properties: +- compatible: + Usage: required + Value type: <string> + Definition: must be "qcom,pdc-timer". + +- reg: + Usage: required + Value type: <prop-encoded-array> + Definition: Specifies the offset of the control register. + Example 1: For a TCS whose RSC base address is is 0x179C0000 and is at a DRV id of 2, the @@ -103,6 +123,9 @@ TCS-OFFSET: 0xD00 <0x179d0000 0x10000>, <0x179e0000 0x10000>; reg-names = "drv-0", "drv-1", "drv-2"; + #address-cells = <1>; + #size-cells = <1>; + ranges; interrupts = <GIC_SPI 3 IRQ_TYPE_LEVEL_HIGH>, <GIC_SPI 4 IRQ_TYPE_LEVEL_HIGH>, <GIC_SPI 5 IRQ_TYPE_LEVEL_HIGH>; @@ -112,6 +135,12 @@ TCS-OFFSET: 0xD00 <SLEEP_TCS 3>, <WAKE_TCS 3>, <CONTROL_TCS 1>; + + pdc_timer@38 { + compatible = "qcom,pdc-timer"; + reg = <0x38 0x1>, + <0x40 0x1>; + } }; Example 2: -- QUALCOMM INDIA, on behalf of Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum, hosted by The Linux Foundation.