Documentation/devicetree/bindings/cpufreq/nvidia,tegra20-cpufreq.txt

   1 Binding for NVIDIA Tegra20 CPUFreq
   2 ==================================
   3
   4 Required properties:
   5 - clocks: Must contain an entry for the CPU clock.
   6   See ../clocks/clock-bindings.txt for details.
   7 - operating-points-v2: See ../bindings/opp/opp.txt for details.
   8 - #cooling-cells: Should be 2. See ../thermal/thermal-cooling-devices.yaml for details.
   9
  10 For each opp entry in 'operating-points-v2' table:
  11 - opp-supported-hw: Two bitfields indicating:
  12         On Tegra20:
  13         1. CPU process ID mask
  14         2. SoC speedo ID mask
  15
  16         On Tegra30:
  17         1. CPU process ID mask
  18         2. CPU speedo ID mask
  19
  20         A bitwise AND is performed against these values and if any bit
  21         matches, the OPP gets enabled.
  22
  23 - opp-microvolt: CPU voltage triplet.
  24
  25 Optional properties:
  26 - cpu-supply: Phandle to the CPU power supply.
  27
  28 Example:
  29         regulators {
  30                 cpu_reg: regulator0 {
  31                         regulator-name = "vdd_cpu";
  32                 };
  33         };
  34
  35         cpu0_opp_table: opp_table0 {
  36                 compatible = "operating-points-v2";
  37
  38                 opp@456000000 {
  39                         clock-latency-ns = <125000>;
  40                         opp-microvolt = <825000 825000 1125000>;
  41                         opp-supported-hw = <0x03 0x0001>;
  42                         opp-hz = /bits/ 64 <456000000>;
  43                 };
  44
  45                 ...
  46         };
  47
  48         cpus {
  49                 cpu@0 {
  50                         compatible = "arm,cortex-a9";
  51                         clocks = <&tegra_car TEGRA20_CLK_CCLK>;
  52                         operating-points-v2 = <&cpu0_opp_table>;
  53                         cpu-supply = <&cpu_reg>;
  54                         #cooling-cells = <2>;
  55                 };
  56         };