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+Allwinner Technologies, Inc. NVMEM CPUFreq and OPP bindings
+===================================
+
+For some SoCs, the CPU frequency subset and voltage value of each OPP
+varies based on the silicon variant in use. Allwinner Process Voltage
+Scaling Tables defines the voltage and frequency value based on the
+speedbin blown in the efuse combination. The sun50i-cpufreq-nvmem driver
+reads the efuse value from the SoC to provide the OPP framework with
+required information.
+
+Required properties:
+--------------------
+In 'cpus' nodes:
+- operating-points-v2: Phandle to the operating-points-v2 table to use.
+
+In 'operating-points-v2' table:
+- compatible: Should be
+ - 'allwinner,sun50i-h6-operating-points'.
+- nvmem-cells: A phandle pointing to a nvmem-cells node representing the
+ efuse registers that has information about the speedbin
+ that is used to select the right frequency/voltage value
+ pair. Please refer the for nvmem-cells bindings
+ Documentation/devicetree/bindings/nvmem/nvmem.txt and
+ also examples below.
+
+In every OPP node:
+- opp-microvolt-<name>: Voltage in micro Volts.
+ At runtime, the platform can pick a <name> and
+ matching opp-microvolt-<name> property.
+ [See: opp.txt]
+ HW: <name>:
+ sun50i-h6 speed0 speed1 speed2
+
+Example 1:
+---------
+
+ cpus {
+ #address-cells = <1>;
+ #size-cells = <0>;
+
+ cpu0: cpu@0 {
+ compatible = "arm,cortex-a53";
+ device_type = "cpu";
+ reg = <0>;
+ enable-method = "psci";
+ clocks = <&ccu CLK_CPUX>;
+ clock-latency-ns = <244144>; /* 8 32k periods */
+ operating-points-v2 = <&cpu_opp_table>;
+ #cooling-cells = <2>;
+ };
+
+ cpu1: cpu@1 {
+ compatible = "arm,cortex-a53";
+ device_type = "cpu";
+ reg = <1>;
+ enable-method = "psci";
+ clocks = <&ccu CLK_CPUX>;
+ clock-latency-ns = <244144>; /* 8 32k periods */
+ operating-points-v2 = <&cpu_opp_table>;
+ #cooling-cells = <2>;
+ };
+
+ cpu2: cpu@2 {
+ compatible = "arm,cortex-a53";
+ device_type = "cpu";
+ reg = <2>;
+ enable-method = "psci";
+ clocks = <&ccu CLK_CPUX>;
+ clock-latency-ns = <244144>; /* 8 32k periods */
+ operating-points-v2 = <&cpu_opp_table>;
+ #cooling-cells = <2>;
+ };
+
+ cpu3: cpu@3 {
+ compatible = "arm,cortex-a53";
+ device_type = "cpu";
+ reg = <3>;
+ enable-method = "psci";
+ clocks = <&ccu CLK_CPUX>;
+ clock-latency-ns = <244144>; /* 8 32k periods */
+ operating-points-v2 = <&cpu_opp_table>;
+ #cooling-cells = <2>;
+ };
+ };
+
+ cpu_opp_table: opp_table {
+ compatible = "allwinner,sun50i-h6-operating-points";
+ nvmem-cells = <&speedbin_efuse>;
+ opp-shared;
+
+ opp@480000000 {
+ clock-latency-ns = <244144>; /* 8 32k periods */
+ opp-hz = /bits/ 64 <480000000>;
+
+ opp-microvolt-speed0 = <880000>;
+ opp-microvolt-speed1 = <820000>;
+ opp-microvolt-speed2 = <800000>;
+ };
+
+ opp@720000000 {
+ clock-latency-ns = <244144>; /* 8 32k periods */
+ opp-hz = /bits/ 64 <720000000>;
+
+ opp-microvolt-speed0 = <880000>;
+ opp-microvolt-speed1 = <820000>;
+ opp-microvolt-speed2 = <800000>;
+ };
+
+ opp@816000000 {
+ clock-latency-ns = <244144>; /* 8 32k periods */
+ opp-hz = /bits/ 64 <816000000>;
+
+ opp-microvolt-speed0 = <880000>;
+ opp-microvolt-speed1 = <820000>;
+ opp-microvolt-speed2 = <800000>;
+ };
+
+ opp@888000000 {
+ clock-latency-ns = <244144>; /* 8 32k periods */
+ opp-hz = /bits/ 64 <888000000>;
+
+ opp-microvolt-speed0 = <940000>;
+ opp-microvolt-speed1 = <820000>;
+ opp-microvolt-speed2 = <800000>;
+ };
+
+ opp@1080000000 {
+ clock-latency-ns = <244144>; /* 8 32k periods */
+ opp-hz = /bits/ 64 <1080000000>;
+
+ opp-microvolt-speed0 = <1060000>;
+ opp-microvolt-speed1 = <880000>;
+ opp-microvolt-speed2 = <840000>;
+ };
+
+ opp@1320000000 {
+ clock-latency-ns = <244144>; /* 8 32k periods */
+ opp-hz = /bits/ 64 <1320000000>;
+
+ opp-microvolt-speed0 = <1160000>;
+ opp-microvolt-speed1 = <940000>;
+ opp-microvolt-speed2 = <900000>;
+ };
+
+ opp@1488000000 {
+ clock-latency-ns = <244144>; /* 8 32k periods */
+ opp-hz = /bits/ 64 <1488000000>;
+
+ opp-microvolt-speed0 = <1160000>;
+ opp-microvolt-speed1 = <1000000>;
+ opp-microvolt-speed2 = <960000>;
+ };
+ };
+....
+soc {
+....
+ sid: sid@3006000 {
+ compatible = "allwinner,sun50i-h6-sid";
+ reg = <0x03006000 0x400>;
+ #address-cells = <1>;
+ #size-cells = <1>;
+ ....
+ speedbin_efuse: speed@1c {
+ reg = <0x1c 4>;
+ };
+ };
+};