xref: /linux/Documentation/devicetree/bindings/cpufreq/nvidia,tegra20-cpufreq.txt (revision 3d0fe49454652117522f60bfbefb978ba0e5300b)
1Binding 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	};
57