Documentation/devicetree/bindings/arm/msm/lpm-levels.txt - kernel/msm-4.9 - Gitiles

 * 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 System low power modes based on
 the latency/residency information of the individual CPUs and clusters.

 LPM-levels defines a hierarchy of low power modes that a cluster and
 clusters/cpus within that cluster can enter. The bottom hierarchy level
 represents the low power modes that a CPU can enter. The CPU low power nodes
 are associated with a cluster that defines the low power modes that a cluster
 can enter. For system involving a hierarchy of clusters, the cluster low power
 modes can be contained within another cluster.

 [Top Level Node]
 Required properties:

 - compatible: "qcom,lpm-levels"

 [Node bindings for qcom,pm-cluster]
  Required properties:
 	- reg - The numeric cluster id
 	- label: Identifies the cluster name. The name is used when reporting
 	the stats for each low power mode.
 	- qcom,psci-mode-shift: The property is used to determine with bit
 	location of the cluster mode in the composite state ID used to define
 	cluster low power modes in PSCI.
 	- qcom,psci-mode-mask: The property is used to determine with bit
 	mask of the cluster mode in the composite state ID used to define
 	cluster low power modes in PSCI.

 	qcom,pm-cluster contains qcom,pm-cluster-level nodes which identify
 	the various low power modes that the cluster can enter. The
 	qcom,pm-cluster node should also include another cluster node or a cpu
 	node that defines their respective low power modes.

 [Node bindings for qcom,pm-cluster-level]
  Required properties:
 	- reg: The numeric cluster level id
 	- label: Name to identify the low power mode in stats
 	module.
 	- qcom,psci-mode: ID to be passed into the PSCI firmware.
 	- qcom,min-child-idx: The minimum level that a child CPU should be in
 	before this level can be chosen. This property is required for all
         non-default level.
 	- 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

  Optional properties:
 	- qcom,notify-rpm: When set, the driver configures the sleep and wake
 	sets. It also configures the next wakeup time for APPS.
 	- qcom,is-reset: This boolean property tells whether cluster level need
 	power management notifications to be sent out or not for the drivers to
 	prepare for cluster collapse.
 	- qcom,reset-level: This property is used to determine in this
 	low power mode only control logic power collapse happens or memory
 	logic power collapse aswell happens or retention state.
 	The accepted values for this property are:
 		"LPM_RESET_LVL_NONE" - No power collapse
 		"LPM_RESET_LVL_RET"  - Retention state
 		"LPM_RESET_LVL_GDHS" - Only control logic power collapse (GDHS)
 		"LPM_RESET_LVL_PC" - Control logic and memory logic
 					power collapse (PC)

 [Node bindings for qcom,pm-cpu]
 qcom,pm-cpu contains the low power modes that a cpu could enter and the CPUs
 that share the parameters.It contains the following properties.
 	- qcom,cpu: List of CPU phandles to identify the CPUs associated with
 	this cluster.
 	- qcom,psci-mode-shift: Same as cluster level fields.
 	- qcom,psci-mode-mask: Same as cluster level fields.
 	- qcom,pm-cpu-levels: The different low power modes that a CPU could
 	enter. The following section explains the required properties of this
 	node.

 [Node bindings for qcom,pm-cpu-levels]
  Required properties:
 	- reg: The numeric cpu level id
 	- label: Name to identify the low power mode in stats
 	- qcom,psci-cpu-mode: ID to be passed into PSCI firmware.
 	- 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

  Optional properties:
 	- qcom,is-reset: This boolean property maps to "power state" bit in PSCI
 	state_id configuration. This property will tell whether CPU get reset for
 	a particular LPM or not. This property is also used to notify the drivers
 	in case of cpu reset.
 	- qcom,use-broadcast-timer: Indicates that the timer gets reset during
 	power collapse and the cpu relies on Broadcast timer for scheduled wakeups.
 	Required only for states where the CPUs internal timer state is lost.

 [Example dts]

 	qcom,lpm-levels {
 		compatible = "qcom,lpm-levels";
 		#address-cells = <1>;
 		#size-cells = <0>;

 		qcom,pm-cluster@0 {
 			reg = <0>;
 			#address-cells = <1>;
 			#size-cells = <0>;
 			label = "L3";
 			qcom,psci-mode-shift = <4>;
 			qcom,psci-mode-mask = <0xfff>;

 			qcom,pm-cluster-level@0 { /* D1 */
 				reg = <0>;
 				label = "l3-wfi";
 				qcom,psci-mode = <0x1>;
 				qcom,latency-us = <51>;
 				qcom,ss-power = <452>;
 				qcom,energy-overhead = <69355>;
 				qcom,time-overhead = <99>;
 			};

 			qcom,pm-cluster-level@1 { /* D2 */
 				reg = <1>;
 				label = "l3-dyn-ret";
 				qcom,psci-mode = <0x2>;
 				qcom,latency-us = <659>;
 				qcom,ss-power = <434>;
 				qcom,energy-overhead = <465725>;
 				qcom,time-overhead = <976>;
 				qcom,min-child-idx = <1>;
 			};

 			qcom,pm-cluster-level@2 { /* D4, D3 is not supported */
 				reg = <2>;
 				label = "l3-pc";
 				qcom,psci-mode = <0x4>;
 				qcom,latency-us = <4562>;
 				qcom,ss-power = <408>;
 				qcom,energy-overhead = <2421840>;
 				qcom,time-overhead = <5376>;
 				qcom,min-child-idx = <2>;
 				qcom,is-reset;
 			};

 			qcom,pm-cluster-level@3 { /* Cx off */
 				reg = <3>;
 				label = "cx-off";
 				qcom,psci-mode = <0x224>;
 				qcom,latency-us = <5562>;
 				qcom,ss-power = <308>;
 				qcom,energy-overhead = <2521840>;
 				qcom,time-overhead = <6376>;
 				qcom,min-child-idx = <3>;
 				qcom,is-reset;
 				qcom,notify-rpm;
 			};

 			qcom,pm-cluster-level@4 { /* LLCC off, AOSS sleep */
 				reg = <4>;
 				label = "llcc-off";
 				qcom,psci-mode = <0xC24>;
 				qcom,latency-us = <6562>;
 				qcom,ss-power = <108>;
 				qcom,energy-overhead = <2621840>;
 				qcom,time-overhead = <7376>;
 				qcom,min-child-idx = <3>;
 				qcom,is-reset;
 				qcom,notify-rpm;
 			};

 			qcom,pm-cpu@0 {
 				#address-cells = <1>;
 				#size-cells = <0>;
 				qcom,psci-mode-shift = <0>;
 				qcom,psci-mode-mask = <0xf>;
 				qcom,cpu = <&CPU0 &CPU1 &CPU2 &CPU3>;

 				qcom,pm-cpu-level@0 { /* C1 */
 					reg = <0>;
 					label = "wfi";
 					qcom,psci-cpu-mode = <0x1>;
 					qcom,latency-us = <43>;
 					qcom,ss-power = <454>;
 					qcom,energy-overhead = <38639>;
 					qcom,time-overhead = <83>;
 				};

 				qcom,pm-cpu-level@1 { /* C2D */
 					reg = <1>;
 					label = "ret";
 					qcom,psci-cpu-mode = <0x2>;
 					qcom,latency-us = <86>;
 					qcom,ss-power = <449>;
 					qcom,energy-overhead = <78456>;
 					qcom,time-overhead = <167>;
 				};

 				qcom,pm-cpu-level@2 {  /* C3 */
 					reg = <2>;
 					label = "pc";
 					qcom,psci-cpu-mode = <0x3>;
 					qcom,latency-us = <612>;
 					qcom,ss-power = <436>;
 					qcom,energy-overhead = <418225>;
 					qcom,time-overhead = <885>;
 					qcom,is-reset;
 				};

 				qcom,pm-cpu-level@3 {  /* C4 */
 					reg = <3>;
 					label = "rail-pc";
 					qcom,psci-cpu-mode = <0x4>;
 					qcom,latency-us = <700>;
 					qcom,ss-power = <400>;
 					qcom,energy-overhead = <428225>;
 					qcom,time-overhead = <1000>;
 					qcom,is-reset;
 				};
 			};

 			qcom,pm-cpu@1 {
 				#address-cells = <1>;
 				#size-cells = <0>;
 				qcom,psci-mode-shift = <0>;
 				qcom,psci-mode-mask = <0xf>;
 				qcom,cpu = <&CPU4 &CPU5 &CPU6 &CPU7>;

 				qcom,pm-cpu-level@0 { /* C1 */
 					reg = <0>;
 					label = "wfi";
 					qcom,psci-cpu-mode = <0x1>;
 					qcom,latency-us = <43>;
 					qcom,ss-power = <454>;
 					qcom,energy-overhead = <38639>;
 					qcom,time-overhead = <83>;
 				};

 				qcom,pm-cpu-level@1 { /* C2D */
 					reg = <1>;
 					label = "ret";
 					qcom,psci-cpu-mode = <0x2>;
 					qcom,latency-us = <86>;
 					qcom,ss-power = <449>;
 					qcom,energy-overhead = <78456>;
 					qcom,time-overhead = <167>;
 				};

 				qcom,pm-cpu-level@2 {  /* C3 */
 					reg = <2>;
 					label = "pc";
 					qcom,psci-cpu-mode = <0x3>;
 					qcom,latency-us = <612>;
 					qcom,ss-power = <436>;
 					qcom,energy-overhead = <418225>;
 					qcom,time-overhead = <885>;
 					qcom,is-reset;
 				};

 				qcom,pm-cpu-level@3 {  /* C4 */
 					reg = <3>;
 					label = "rail-pc";
 					qcom,psci-cpu-mode = <0x4>;
 					qcom,latency-us = <700>;
 					qcom,ss-power = <400>;
 					qcom,energy-overhead = <428225>;
 					qcom,time-overhead = <1000>;
 					qcom,is-reset;
 				};
 			};
 		};
 	};
	* 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 System low power modes based on
	the latency/residency information of the individual CPUs and clusters.

	LPM-levels defines a hierarchy of low power modes that a cluster and
	clusters/cpus within that cluster can enter. The bottom hierarchy level
	represents the low power modes that a CPU can enter. The CPU low power nodes
	are associated with a cluster that defines the low power modes that a cluster
	can enter. For system involving a hierarchy of clusters, the cluster low power
	modes can be contained within another cluster.

	[Top Level Node]
	Required properties:

	- compatible: "qcom,lpm-levels"

	[Node bindings for qcom,pm-cluster]
	Required properties:
	- reg - The numeric cluster id
	- label: Identifies the cluster name. The name is used when reporting
	the stats for each low power mode.
	- qcom,psci-mode-shift: The property is used to determine with bit
	location of the cluster mode in the composite state ID used to define
	cluster low power modes in PSCI.
	- qcom,psci-mode-mask: The property is used to determine with bit
	mask of the cluster mode in the composite state ID used to define
	cluster low power modes in PSCI.

	qcom,pm-cluster contains qcom,pm-cluster-level nodes which identify
	the various low power modes that the cluster can enter. The
	qcom,pm-cluster node should also include another cluster node or a cpu
	node that defines their respective low power modes.

	[Node bindings for qcom,pm-cluster-level]
	Required properties:
	- reg: The numeric cluster level id
	- label: Name to identify the low power mode in stats
	module.
	- qcom,psci-mode: ID to be passed into the PSCI firmware.
	- qcom,min-child-idx: The minimum level that a child CPU should be in
	before this level can be chosen. This property is required for all
	non-default level.
	- 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

	Optional properties:
	- qcom,notify-rpm: When set, the driver configures the sleep and wake
	sets. It also configures the next wakeup time for APPS.
	- qcom,is-reset: This boolean property tells whether cluster level need
	power management notifications to be sent out or not for the drivers to
	prepare for cluster collapse.
	- qcom,reset-level: This property is used to determine in this
	low power mode only control logic power collapse happens or memory
	logic power collapse aswell happens or retention state.
	The accepted values for this property are:
	"LPM_RESET_LVL_NONE" - No power collapse
	"LPM_RESET_LVL_RET" - Retention state
	"LPM_RESET_LVL_GDHS" - Only control logic power collapse (GDHS)
	"LPM_RESET_LVL_PC" - Control logic and memory logic
	power collapse (PC)

	[Node bindings for qcom,pm-cpu]
	qcom,pm-cpu contains the low power modes that a cpu could enter and the CPUs
	that share the parameters.It contains the following properties.
	- qcom,cpu: List of CPU phandles to identify the CPUs associated with
	this cluster.
	- qcom,psci-mode-shift: Same as cluster level fields.
	- qcom,psci-mode-mask: Same as cluster level fields.
	- qcom,pm-cpu-levels: The different low power modes that a CPU could
	enter. The following section explains the required properties of this
	node.

	[Node bindings for qcom,pm-cpu-levels]
	Required properties:
	- reg: The numeric cpu level id
	- label: Name to identify the low power mode in stats
	- qcom,psci-cpu-mode: ID to be passed into PSCI firmware.
	- 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

	Optional properties:
	- qcom,is-reset: This boolean property maps to "power state" bit in PSCI
	state_id configuration. This property will tell whether CPU get reset for
	a particular LPM or not. This property is also used to notify the drivers
	in case of cpu reset.
	- qcom,use-broadcast-timer: Indicates that the timer gets reset during
	power collapse and the cpu relies on Broadcast timer for scheduled wakeups.
	Required only for states where the CPUs internal timer state is lost.

	[Example dts]

	qcom,lpm-levels {
	compatible = "qcom,lpm-levels";
	#address-cells = <1>;
	#size-cells = <0>;

	qcom,pm-cluster@0 {
	reg = <0>;
	#address-cells = <1>;
	#size-cells = <0>;
	label = "L3";
	qcom,psci-mode-shift = <4>;
	qcom,psci-mode-mask = <0xfff>;

	qcom,pm-cluster-level@0 { /* D1 */
	reg = <0>;
	label = "l3-wfi";
	qcom,psci-mode = <0x1>;
	qcom,latency-us = <51>;
	qcom,ss-power = <452>;
	qcom,energy-overhead = <69355>;
	qcom,time-overhead = <99>;
	};

	qcom,pm-cluster-level@1 { /* D2 */
	reg = <1>;
	label = "l3-dyn-ret";
	qcom,psci-mode = <0x2>;
	qcom,latency-us = <659>;
	qcom,ss-power = <434>;
	qcom,energy-overhead = <465725>;
	qcom,time-overhead = <976>;
	qcom,min-child-idx = <1>;
	};

	qcom,pm-cluster-level@2 { /* D4, D3 is not supported */
	reg = <2>;
	label = "l3-pc";
	qcom,psci-mode = <0x4>;
	qcom,latency-us = <4562>;
	qcom,ss-power = <408>;
	qcom,energy-overhead = <2421840>;
	qcom,time-overhead = <5376>;
	qcom,min-child-idx = <2>;
	qcom,is-reset;
	};

	qcom,pm-cluster-level@3 { /* Cx off */
	reg = <3>;
	label = "cx-off";
	qcom,psci-mode = <0x224>;
	qcom,latency-us = <5562>;
	qcom,ss-power = <308>;
	qcom,energy-overhead = <2521840>;
	qcom,time-overhead = <6376>;
	qcom,min-child-idx = <3>;
	qcom,is-reset;
	qcom,notify-rpm;
	};

	qcom,pm-cluster-level@4 { /* LLCC off, AOSS sleep */
	reg = <4>;
	label = "llcc-off";
	qcom,psci-mode = <0xC24>;
	qcom,latency-us = <6562>;
	qcom,ss-power = <108>;
	qcom,energy-overhead = <2621840>;
	qcom,time-overhead = <7376>;
	qcom,min-child-idx = <3>;
	qcom,is-reset;
	qcom,notify-rpm;
	};

	qcom,pm-cpu@0 {
	#address-cells = <1>;
	#size-cells = <0>;
	qcom,psci-mode-shift = <0>;
	qcom,psci-mode-mask = <0xf>;
	qcom,cpu = <&CPU0 &CPU1 &CPU2 &CPU3>;

	qcom,pm-cpu-level@0 { /* C1 */
	reg = <0>;
	label = "wfi";
	qcom,psci-cpu-mode = <0x1>;
	qcom,latency-us = <43>;
	qcom,ss-power = <454>;
	qcom,energy-overhead = <38639>;
	qcom,time-overhead = <83>;
	};

	qcom,pm-cpu-level@1 { /* C2D */
	reg = <1>;
	label = "ret";
	qcom,psci-cpu-mode = <0x2>;
	qcom,latency-us = <86>;
	qcom,ss-power = <449>;
	qcom,energy-overhead = <78456>;
	qcom,time-overhead = <167>;
	};

	qcom,pm-cpu-level@2 { /* C3 */
	reg = <2>;
	label = "pc";
	qcom,psci-cpu-mode = <0x3>;
	qcom,latency-us = <612>;
	qcom,ss-power = <436>;
	qcom,energy-overhead = <418225>;
	qcom,time-overhead = <885>;
	qcom,is-reset;
	};

	qcom,pm-cpu-level@3 { /* C4 */
	reg = <3>;
	label = "rail-pc";
	qcom,psci-cpu-mode = <0x4>;
	qcom,latency-us = <700>;
	qcom,ss-power = <400>;
	qcom,energy-overhead = <428225>;
	qcom,time-overhead = <1000>;
	qcom,is-reset;
	};
	};

	qcom,pm-cpu@1 {
	#address-cells = <1>;
	#size-cells = <0>;
	qcom,psci-mode-shift = <0>;
	qcom,psci-mode-mask = <0xf>;
	qcom,cpu = <&CPU4 &CPU5 &CPU6 &CPU7>;

	qcom,pm-cpu-level@0 { /* C1 */
	reg = <0>;
	label = "wfi";
	qcom,psci-cpu-mode = <0x1>;
	qcom,latency-us = <43>;
	qcom,ss-power = <454>;
	qcom,energy-overhead = <38639>;
	qcom,time-overhead = <83>;
	};

	qcom,pm-cpu-level@1 { /* C2D */
	reg = <1>;
	label = "ret";
	qcom,psci-cpu-mode = <0x2>;
	qcom,latency-us = <86>;
	qcom,ss-power = <449>;
	qcom,energy-overhead = <78456>;
	qcom,time-overhead = <167>;
	};

	qcom,pm-cpu-level@2 { /* C3 */
	reg = <2>;
	label = "pc";
	qcom,psci-cpu-mode = <0x3>;
	qcom,latency-us = <612>;
	qcom,ss-power = <436>;
	qcom,energy-overhead = <418225>;
	qcom,time-overhead = <885>;
	qcom,is-reset;
	};

	qcom,pm-cpu-level@3 { /* C4 */
	reg = <3>;
	label = "rail-pc";
	qcom,psci-cpu-mode = <0x4>;
	qcom,latency-us = <700>;
	qcom,ss-power = <400>;
	qcom,energy-overhead = <428225>;
	qcom,time-overhead = <1000>;
	qcom,is-reset;
	};
	};
	};
	};