kernel_samsung_msm8974/Documentation/devicetree/bindings/arm/msm/lpm-levels.txt

* Low Power Management Levels

The application processor in MSM can do a variety of C-States for low power
management. The LPM module performs the CPU and System low power modes based
on it latency and residency information of the individual CPU/System low power
levels.

The first level node represents the properties of the system and includes
second level node to represent the low power modes of cpu and system.

[First Level Nodes]
Required properties:

- compatible: "qcom,lpm-levels"

The optional nodes for the First level nodes are:
- qcom,no-l2-saw: Indicates if this target has an L2 SAW (SPM and AVS wrapper).
- qcom,default-l2-state: Indicates what the default low power state of the L2
		SAW should be. This property should be mentioned when there is
		a L2 saw.
- qcom,allow-synced-levels:  Indicates if certain low power modes should be
		synchronized across all cores so as to configure a system
		low power mode.

[Second Level Nodes]
Required properties to define CPU low power modes :
- compatible = "qcom,cpu-modes";
- qcom,mode: The sleep mode of the processor, values for the property are:
		"wfi" - Wait for Interrupt
		"retention" - Retention
		"standalone_pc" - Standalone power collapse
		"pc" - Power Collapse
- qcom,latency-us: The latency in handling the interrupt if this level was
		chosen, in uSec
- qcom,ss-power: The steady state power expelled when the processor is in this
		 level in mWatts
- qcom,energy-overhead: The energy used up in entering and exiting this level
		 in mWatts.uSec
- qcom,time-overhead: The time spent in entering and exiting this level in uS

Required propertieis to define System low power mode :
- compatible: "qcom,system-modes"
- qcom,l2: The state of L2 cache. Values are:
		"l2_cache_pc" - L2 cache in power collapse
		"l2_cache_pc_no_rpm" - L2 cache in power collapse. This mode
				wouldn't inform the RPM
		"l2_cache_retenetion" - L2 cache in retention
		"l2_cache_gdhs" - L2 cache in GDHS
		"l2_cache_active" - L2 cache in active mode

- qcom,latency-us: The latency in handling the interrupt if this level was
		chosen, in uSec
- qcom,ss-power: The steady state power expelled when the processor is in this
		 level in mWatts
- qcom,energy-overhead: The energy used up in entering and exiting this level
		 in mWatts.uSec
- qcom,time-overhead: The time spent in entering and exiting this level in uS
- qcom,min-cpu-mode: The min cpu sleep mode at which the given system level is
		 valid. All cpus should have entered this low power mode before
		 this system level can be chosen.
- qcom,send-rpm-sleep-set: The system mode notifies RPM of Apps sleep and should
		send the current sleep set votes and configure MPM before
		entering this low power mode.

Example:
qcom,lpm-levels {
		compatible = "qcom,lpm-levels";
		qcom,default-l2-state = "l2_cache_retention";
		#address-cells = <1>;
		#size-cells = <1>;

		qcom,cpu-modes {
			compatible = "qcom,cpu-modes";
			qcom,cpu-mode@0 {
				qcom,mode = "wfi";
				qcom,latency-us = <1>;
				qcom,ss-power = <715>;
				qcom,energy-overhead = <17700>;
				qcom,time-overhead = <2>;
			};

			qcom,cpu-mode@1 {
				qcom,mode = "retention";
				qcom,latency-us = <35>;
				qcom,ss-power = <542>;
				qcom,energy-overhead = <34920>;
				qcom,time-overhead = <40>;
			};
		};
		qcom,system-modes {
			compatible = "qcom,system-modes";

			qcom,system-mode@0 {
				qcom,l2 = "l2_cache_gdhs";
				qcom,latency-us = <20000>;
				qcom,ss-power = <163>;
				qcom,energy-overhead = <1577736>;
				qcom,time-overhead = <5067>;
			};

			qcom,system-mode@1 {
				qcom,l2 = "l2_cache_pc";
				qcom,latency-us = <30000>;
				qcom,ss-power = <83>;
				qcom,energy-overhead = <2274420>;
				qcom,time-overhead = <6605>;
			};
		};
};