Qualcomm Technologies, Inc. CPR4 Regulator - APSS Specific Bindings APSS CPR4 controllers each support one CPR thread that monitors the voltage of a pair of application processor (APSS) clusters that are powered by a shared regulator supply. They also have a hardware channel to use these requests to directly change the supply voltage at the PMIC via the SPM without software intervention. APSS CPR4 controllers also have to take into account the state of the memory array power mux (APM) when scaling voltage to ensure that memory always receives a sufficiently high voltage. Both CPR open-loop voltages and CPR target quotients are stored in hardware fuses for APSS CPR4 controllers. This document describes the APSS specific CPR4 bindings. ======================= Required Node Structure ======================= CPR4 regulators must be described in three levels of devices nodes. The first level describes the CPR4 controller. The second level describes one or more hardware threads managed by the controller. The third level describes one or more logical regulators handled by each CPR thread. All platform independent cpr3-regulator binding guidelines defined in cpr3-regulator.txt also apply to cpr4-apss-regulator devices. ==================================== First Level Nodes - CPR4 Controllers ==================================== APSS specific properties: - compatible Usage: required Value type: Definition: should be one of the following: "qcom,cpr4-msmtitanium-apss-regulator"; - interrupts Usage: required Value type: Definition: CPR interrupt specifier and a hardware closed-loop ceiling interrupt specifier. - interrupt-names Usage: required Value type: Definition: Interrupt names. This list must match up 1-to-1 with the interrupts specified in the 'interrupts' property. "cpr" and "ceiling" must be specified. - qcom,apm-ctrl Usage: required on systems that need APM management Value type: Definition: phandle of memory array power mux (APM) controller device node for the APM that is used by the APSS VDD supply - qcom,apm-threshold-voltage Usage: required if qcom,apm-ctrl is specified Value type: Definition: Specifies the APM threshold voltage in microvolts. If the vdd-supply voltage is greater than or equal to this level, then the APM is switched to use the vdd-supply. If the vdd-supply voltage is below this level, then the APM is switched to use the system-supply. - qcom,apm-hysteresis-voltage Usage: optional Value type: Definition: Specifies the voltage delta in microvolts between the APM threshold voltage and the highest corner open-loop voltage which may be used as the ceiling for the corner. If this property is not specified, then a value of 0 is assumed. - qcom,cpr-hw-closed-loop Usage: optional Value type: Definition: Boolean flag which indicates that the APSS CPR4 controller should operate in hardware closed-loop mode as opposed to software closed-loop mode. - vdd-limit-supply Usage: required Value type: Definition: phandle of the VDD supply limit regulator which controls the CPR ceiling and floor voltages when operating in hardware closed-loop mode. - qcom,cpr-down-error-step-limit Usage: required Value type: Definition: CPR4 hardware closed-loop down error step limit which defines the maximum number of vdd-supply regulator steps that the voltage may be reduced as the result of a single CPR measurement. - qcom,cpr-up-error-step-limit Usage: required Value type: Definition: CPR4 hardware closed-loop up error step limit which defines the maximum number of vdd-supply regulator steps that the voltage may be increased as the result of a single CPR measurement. - qcom,cpr-saw-use-unit-mV Usage: optional Value type: Definition: Boolean flag which indicates that the unit used in SAW PVC interface is mV. Use this for vdd-supply regulators which do not use PMIC voltage control register LSBs per actually unique PMIC regulator output voltage. ================================================= Second Level Nodes - CPR Threads for a Controller ================================================= APSS specific properties: N/A =============================================== Third Level Nodes - CPR Regulators for a Thread =============================================== APSS specific properties: - qcom,cpr-fuse-corners Usage: required Value type: Definition: Specifies the number of fuse corners. This value must be 4 for APSS. These fuse corners are: LowSVS, SVS, Nominal, and Turbo. - qcom,cpr-fuse-combos Usage: required Value type: Definition: Specifies the number of fuse combinations being supported by the device. This value is utilized by several other properties. Supported values are 1 up to the maximum possible for a given regulator type. For APSS the maximum supported value is 64. The first 8 fuse combos correspond to speed bin fuse value 0 along with CPR revision fuse values 0 to 7. The second 8 fuse combos correspond to speed bin fuse value 1 along with CPR revision fuse values 0 to 7. The last 8 fuse combos correspond to speed bin fuse value 7 along with CPR revision fuse values 0 to 7. - qcom,cpr-speed-bins Usage: optional Value type: Definition: Specifies the number of speed bins being supported by the device. This value is utilized by several other properties. Supported values are 1 up to the maximum possible for a given regulator type. For APSS the maximum supported value is 8. - qcom,mem-acc-voltage Usage: required if mem-acc-supply is specified for the CPR4 controller containing this regulator Value type: Definition: A list of integer tuples which each define the mem-acc-supply corner for each voltage corner in order from lowest to highest. The list must contain qcom,cpr-fuse-combos number of tuples in which case the tuples are matched to fuse combinations 1-to-1 or qcom,cpr-speed-bins number of tuples in which case the tuples are matched to speed bins 1-to-1 or exactly 1 tuple which is used regardless of the fuse combination and speed bin found on a given chip. Each tuple must be of the length defined in the corresponding element of the qcom,cpr-corners property or the qcom,cpr-speed-bins property. A single tuple may only be specified if all of the corner counts in qcom,cpr-corners are the same. - qcom,allow-quotient-interpolation Usage: optional Value type: Definition: Boolean flag which indicates that it is acceptable to use interpolated CPR target quotient values. These values are interpolated between the target quotient Fmax fuse values. ======= Example ======= apc_cpr: cpr4-ctrl@b018000 { compatible = "qcom,cpr4-msmtitanium-apss-regulator"; reg = <0xb018000 0x4000>, <0xa4000 0x1000>; reg-names = "cpr_ctrl", "fuse_base"; interrupts = , ; interrupt-names = "cpr", "ceiling"; qcom,cpr-ctrl-name = "apc"; qcom,cpr-sensor-time = <1000>; qcom,cpr-loop-time = <5000000>; qcom,cpr-idle-cycles = <15>; qcom,cpr-step-quot-init-min = <13>; qcom,cpr-step-quot-init-max = <13>; qcom,cpr-count-mode = <2>; /* Staggered */ qcom,cpr-down-error-step-limit = <1>; qcom,cpr-up-error-step-limit = <1>; qcom,apm-ctrl = <&apc_apm>; qcom,apm-threshold-voltage = <848000>; qcom,apm-hysteresis-voltage = <5000>; vdd-supply = <&pmtitanium_s5>; qcom,voltage-step = <5000>; vdd-limit-supply = <&pmtitanium_s5_limit>; mem-acc-supply = <&apc_mem_acc_vreg>; qcom,cpr-enable; qcom,cpr-hw-closed-loop; thread@0 { qcom,cpr-thread-id = <0>; qcom,cpr-consecutive-up = <1>; qcom,cpr-consecutive-down = <1>; qcom,cpr-up-threshold = <1>; qcom,cpr-down-threshold = <1>; apc_vreg: regulator { regulator-name = "apc_corner"; regulator-min-microvolt = <1>; regulator-max-microvolt = <8>; qcom,cpr-fuse-corners = <4>; qcom,cpr-fuse-combos = <8>; qcom,cpr-speed-bins = <1>; qcom,cpr-corners = <8>; qcom,cpr-corner-fmax-map = <1 2 4 8>; qcom,cpr-voltage-ceiling = <645000 720000 790000 865000 920000 990000 1065000 1065000>; qcom,cpr-voltage-floor = <590000 625000 690000 755000 800000 855000 920000 920000>; qcom,mem-acc-voltage = <1 1 2 2 2 2 2 2>; qcom,corner-frequencies = <652800000 1036800000 1401600000 1689600000 1843200000 1958400000 2150400000 2208000000>; qcom,allow-voltage-interpolation; qcom,allow-quotient-interpolation; qcom,cpr-scaled-open-loop-voltage-as-ceiling; }; }; };