watchdog: Fix print-once on enable
[sfrench/cifs-2.6.git] / Documentation / devicetree / bindings / cpufreq / cpufreq-cpu0.txt
1 Generic CPU0 cpufreq driver
2
3 It is a generic cpufreq driver for CPU0 frequency management.  It
4 supports both uniprocessor (UP) and symmetric multiprocessor (SMP)
5 systems which share clock and voltage across all CPUs.
6
7 Both required and optional properties listed below must be defined
8 under node /cpus/cpu@0.
9
10 Required properties:
11 - None
12
13 Optional properties:
14 - operating-points: Refer to Documentation/devicetree/bindings/power/opp.txt for
15   details. OPPs *must* be supplied either via DT, i.e. this property, or
16   populated at runtime.
17 - clock-latency: Specify the possible maximum transition latency for clock,
18   in unit of nanoseconds.
19 - voltage-tolerance: Specify the CPU voltage tolerance in percentage.
20 - #cooling-cells:
21 - cooling-min-level:
22 - cooling-max-level:
23      Please refer to Documentation/devicetree/bindings/thermal/thermal.txt.
24
25 Examples:
26
27 cpus {
28         #address-cells = <1>;
29         #size-cells = <0>;
30
31         cpu@0 {
32                 compatible = "arm,cortex-a9";
33                 reg = <0>;
34                 next-level-cache = <&L2>;
35                 operating-points = <
36                         /* kHz    uV */
37                         792000  1100000
38                         396000  950000
39                         198000  850000
40                 >;
41                 clock-latency = <61036>; /* two CLK32 periods */
42                 #cooling-cells = <2>;
43                 cooling-min-level = <0>;
44                 cooling-max-level = <2>;
45         };
46
47         cpu@1 {
48                 compatible = "arm,cortex-a9";
49                 reg = <1>;
50                 next-level-cache = <&L2>;
51         };
52
53         cpu@2 {
54                 compatible = "arm,cortex-a9";
55                 reg = <2>;
56                 next-level-cache = <&L2>;
57         };
58
59         cpu@3 {
60                 compatible = "arm,cortex-a9";
61                 reg = <3>;
62                 next-level-cache = <&L2>;
63         };
64 };