[PATCH 09/13] dt-bindings: power: avs: Add support for CPR (Core Power Reduction)
From: Niklas Cassel
Date: Fri Jul 05 2019 - 05:58:54 EST
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