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Tom Rini53633a82024-02-29 12:33:36 -05001Binding for NVIDIA Tegra20 CPUFreq
2==================================
3
4Required 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-v2.yaml for details.
8- #cooling-cells: Should be 2. See ../thermal/thermal-cooling-devices.yaml for details.
9
10For 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
25Optional properties:
26- cpu-supply: Phandle to the CPU power supply.
27
28Example:
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 };