* Low Power Management Levels

The application processor in MSM can do a variety of C-States for low power
management. These C-States are invoked by the CPUIdle framework when the core
becomes idle. But based on the time available until the next scheduled wakeup,
the system can do a combination of low power modes of different resources -
L2, XO, Vdd Dig and Vdd Mem. The combination is captured in the device tree as
lpm-level. The units for voltage are dependent on the PMIC used on the target
and are in uV.

The required nodes for lpm-levels are:

- compatible: "qcom,lpm-levels"
- reg: The numeric level id
- qcom,mode: The sleep mode of the processor
- qcom,xo: The state of XO clock.
- qcom,l2: The state of L2 cache.
- qcom,vdd-mem-upper-bound: The upper bound value of mem voltage in uV
- qcom,vdd-mem-lower-bound: The lower bound value of mem voltage in uV
- qcom,vdd-dig-upper-bound: The upper bound value of dig voltage in uV
                            or an RBCPR (Rapid Bridge Core Power Reduction)
                            corner voltage.
- qcom,vdd-dig-lower-bound: The lower bound value of dig voltage in uV
                            or an RBCPR (Rapid Bridge Core Power Reduction)
                            corner voltage.
- 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

Example:

qcom,lpm-levels {
	qcom,lpm-level@0 {
		reg = <0>;
		qcom,mode = <0>;        /* MSM_PM_SLEEP_MODE_WAIT_FOR_INTERRUPT */
		qcom,xo = <1>;          /* ON */
		qcom,l2 = <3>;          /* ACTIVE */
		qcom,vdd-mem-upper-bound = <1150000>; /* MAX */
		qcom,vdd-mem-lower-bound = <1050000>; /* ACTIVE */
		qcom,vdd-dig-upper-bound = <5>; /* MAX */
		qcom,vdd-dig-lower-bound = <3>;  /* ACTIVE */
		qcom,latency-us = <100>;
		qcom,ss-power = <650>;
		qcom,energy-overhead = <801>;
		qcom,time-overhead = <200>;
	};
};
