1SPM AVS Wrapper 2 (SAW2) 2 3The SAW2 is a wrapper around the Subsystem Power Manager (SPM) and the 4Adaptive Voltage Scaling (AVS) hardware. The SPM is a programmable 5power-controller that transitions a piece of hardware (like a processor or 6subsystem) into and out of low power modes via a direct connection to 7the PMIC. It can also be wired up to interact with other processors in the 8system, notifying them when a low power state is entered or exited. 9 10Multiple revisions of the SAW hardware are supported using these Device Nodes. 11SAW2 revisions differ in the register offset and configuration data. Also, the 12same revision of the SAW in different SoCs may have different configuration 13data due the the differences in hardware capabilities. Hence the SoC name, the 14version of the SAW hardware in that SoC and the distinction between cpu (big 15or Little) or cache, may be needed to uniquely identify the SAW register 16configuration and initialization data. The compatible string is used to 17indicate this parameter. 18 19PROPERTIES 20 21- compatible: 22 Usage: required 23 Value type: <string> 24 Definition: Must have 25 "qcom,saw2" 26 A more specific value could be one of: 27 "qcom,apq8064-saw2-v1.1-cpu" 28 "qcom,msm8974-saw2-v2.1-cpu" 29 "qcom,apq8084-saw2-v2.1-cpu" 30 31- reg: 32 Usage: required 33 Value type: <prop-encoded-array> 34 Definition: the first element specifies the base address and size of 35 the register region. An optional second element specifies 36 the base address and size of the alias register region. 37 38- regulator: 39 Usage: optional 40 Value type: boolean 41 Definition: Indicates that this SPM device acts as a regulator device 42 device for the core (CPU or Cache) the SPM is attached 43 to. 44 45Example 1: 46 47 power-controller@2099000 { 48 compatible = "qcom,saw2"; 49 reg = <0x02099000 0x1000>, <0x02009000 0x1000>; 50 regulator; 51 }; 52 53Example 2: 54 saw0: power-controller@f9089000 { 55 compatible = "qcom,apq8084-saw2-v2.1-cpu", "qcom,saw2"; 56 reg = <0xf9089000 0x1000>, <0xf9009000 0x1000>; 57 }; 58