Add DT bindings to describe the CPR HW found on certain Qualcomm SoCs. Changes since RFC: -Make compatible string SoC specific. -Changed interrupt definition. -Use clock binding for reference clock. -Clarified qcom,vdd-apc-step-up-limit description. -Added missing properties. -Updated the example. Co-developed-by: Jorge Ramirez-Ortiz <jorge.ramirez-ortiz@xxxxxxxxxx> Signed-off-by: Jorge Ramirez-Ortiz <jorge.ramirez-ortiz@xxxxxxxxxx> Signed-off-by: Niklas Cassel <niklas.cassel@xxxxxxxxxx> --- .../bindings/power/avs/qcom,cpr.txt | 193 ++++++++++++++++++ 1 file changed, 193 insertions(+) create mode 100644 Documentation/devicetree/bindings/power/avs/qcom,cpr.txt diff --git a/Documentation/devicetree/bindings/power/avs/qcom,cpr.txt b/Documentation/devicetree/bindings/power/avs/qcom,cpr.txt new file mode 100644 index 000000000000..93be67fa8f38 --- /dev/null +++ b/Documentation/devicetree/bindings/power/avs/qcom,cpr.txt @@ -0,0 +1,193 @@ +QCOM CPR (Core Power Reduction) + +CPR (Core Power Reduction) is a technology to reduce core power on a CPU +or other device. Each OPP of a device corresponds to a "corner" that has +a range of valid voltages for a particular frequency. While the device is +running at a particular frequency, CPR monitors dynamic factors such as +temperature, etc. and suggests adjustments to the voltage to save power +and meet silicon characteristic requirements. + +- compatible: + Usage: required + Value type: <string> + Definition: should be "qcom,qcs404-cpr", "qcom,cpr" for qcs404 + +- reg: + Usage: required + Value type: <prop-encoded-array> + Definition: base address and size of the rbcpr register region + +- interrupts: + Usage: required + Value type: <prop-encoded-array> + Definition: should specify the CPR interrupt + +- clocks: + Usage: required + Value type: <prop-encoded-array> + Definition: phandle to the reference clock + +- clock-names: + Usage: required + Value type: <stringlist> + Definition: must be "ref" + +- vdd-apc-supply: + Usage: required + Value type: <phandle> + Definition: phandle to the vdd-apc-supply regulator + +- #power-domain-cells: + Usage: required + Value type: <u32> + Definition: should be 0 + +- operating-points-v2: + Usage: required + Value type: <phandle> + Definition: A phandle to the OPP table containing the + performance states supported by the CPR + power domain + +- acc-syscon: + Usage: optional + Value type: <phandle> + Definition: phandle to syscon for writing ACC settings + +- nvmem-cells: + Usage: required + Value type: <phandle> + Definition: phandle to nvmem cells containing the data + that makes up a fuse corner, for each fuse corner. + As well as the CPR fuse revision. + +- nvmem-cell-names: + Usage: required + Value type: <stringlist> + Definition: should be "cpr_quotient_offset1", "cpr_quotient_offset2", + "cpr_quotient_offset3", "cpr_init_voltage1", + "cpr_init_voltage2", "cpr_init_voltage3", "cpr_quotient1", + "cpr_quotient2", "cpr_quotient3", "cpr_ring_osc1", + "cpr_ring_osc2", "cpr_ring_osc3", "cpr_fuse_revision" + for qcs404. + +- qcom,cpr-timer-delay-us: + Usage: required + Value type: <u32> + Definition: delay in uS for the timer interval + +- qcom,cpr-timer-cons-up: + Usage: required + Value type: <u32> + Definition: Consecutive number of timer intervals, or units of + qcom,cpr-timer-delay-us, that occur before issuing an up + interrupt + +- qcom,cpr-timer-cons-down: + Usage: required + Value type: <u32> + Definition: Consecutive number of timer intervals, or units of + qcom,cpr-timer-delay-us, that occur before issuing a down + interrupt + +- qcom,cpr-up-threshold: + Usage: optional + Value type: <u32> + Definition: The threshold for CPR to issue interrupt when error_steps + is greater than it when stepping up + +- qcom,cpr-down-threshold: + Usage: optional + Value type: <u32> + Definition: The threshold for CPR to issue interrupt when error_steps + is greater than it when stepping down + +- qcom,cpr-idle-clocks: + Usage: optional + Value type: <u32> + Definition: Idle clock cycles ring oscillator can be in + +- qcom,cpr-gcnt-us: + Usage: required + Value type: <u32> + Definition: The time for gate count in uS + +- qcom,vdd-apc-step-up-limit: + Usage: required + Value type: <u32> + Definition: Limit of number of vdd-apc-supply regulator steps for + scaling up + +- qcom,vdd-apc-step-down-limit: + Usage: required + Value type: <u32> + Definition: Limit of number of vdd-apc-supply regulator steps for + scaling down + +Example: + + cpr_opp_table: cpr-opp-table { + compatible = "operating-points-v2-qcom-level"; + + cpr_opp1: opp1 { + opp-level = <1>; + .... + }; + cpr_opp2: opp2 { + opp-level = <2>; + .... + }; + cpr_opp3: opp3 { + opp-level = <3>; + .... + }; + }; + + cpr@b018000 { + compatible = "qcom,qcs404-cpr", "qcom,cpr"; + reg = <0x0b018000 0x1000>; + interrupts = <0 15 IRQ_TYPE_EDGE_RISING>; + clocks = <&xo_board>; + clock-names = "ref"; + vdd-apc-supply = <&pms405_s3>; + #power-domain-cells = <0>; + operating-points-v2 = <&cpr_opp_table>; + acc-syscon = <&tcsr>; + + nvmem-cells = <&cpr_efuse_quot_offset1>, + <&cpr_efuse_quot_offset2>, + <&cpr_efuse_quot_offset3>, + <&cpr_efuse_init_voltage1>, + <&cpr_efuse_init_voltage2>, + <&cpr_efuse_init_voltage3>, + <&cpr_efuse_quot1>, + <&cpr_efuse_quot2>, + <&cpr_efuse_quot3>, + <&cpr_efuse_ring1>, + <&cpr_efuse_ring2>, + <&cpr_efuse_ring3>, + <&cpr_efuse_revision>; + nvmem-cell-names = "cpr_quotient_offset1", + "cpr_quotient_offset2", + "cpr_quotient_offset3", + "cpr_init_voltage1", + "cpr_init_voltage2", + "cpr_init_voltage3", + "cpr_quotient1", + "cpr_quotient2", + "cpr_quotient3", + "cpr_ring_osc1", + "cpr_ring_osc2", + "cpr_ring_osc3", + "cpr_fuse_revision"; + + qcom,cpr-timer-delay-us = <5000>; + qcom,cpr-timer-cons-up = <0>; + qcom,cpr-timer-cons-down = <2>; + qcom,cpr-up-threshold = <1>; + qcom,cpr-down-threshold = <3>; + qcom,cpr-idle-clocks = <15>; + qcom,cpr-gcnt-us = <1>; + qcom,vdd-apc-step-up-limit = <1>; + qcom,vdd-apc-step-down-limit = <1>; + }; -- 2.21.0