Viresh Kumar 1bf8cc3d01 cpufreq: cpu0: OPPs can be populated at runtime
OPPs can be populated statically, via DT, or added at run time with
dev_pm_opp_add().

While this driver handles the first case correctly, it would fail to populate
OPPs added at runtime. Because call to of_init_opp_table() would fail as there
are no OPPs in DT and probe will return early.

To fix this, remove error checking and call dev_pm_opp_init_cpufreq_table()
unconditionally.

Update bindings as well.

Suggested-by: Stephen Boyd <sboyd@codeaurora.org>
Tested-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Acked-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-07-16 15:12:52 +02:00

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Generic CPU0 cpufreq driver
It is a generic cpufreq driver for CPU0 frequency management. It
supports both uniprocessor (UP) and symmetric multiprocessor (SMP)
systems which share clock and voltage across all CPUs.
Both required and optional properties listed below must be defined
under node /cpus/cpu@0.
Required properties:
- None
Optional properties:
- operating-points: Refer to Documentation/devicetree/bindings/power/opp.txt for
details. OPPs *must* be supplied either via DT, i.e. this property, or
populated at runtime.
- clock-latency: Specify the possible maximum transition latency for clock,
in unit of nanoseconds.
- voltage-tolerance: Specify the CPU voltage tolerance in percentage.
- #cooling-cells:
- cooling-min-level:
- cooling-max-level:
Please refer to Documentation/devicetree/bindings/thermal/thermal.txt.
Examples:
cpus {
#address-cells = <1>;
#size-cells = <0>;
cpu@0 {
compatible = "arm,cortex-a9";
reg = <0>;
next-level-cache = <&L2>;
operating-points = <
/* kHz uV */
792000 1100000
396000 950000
198000 850000
>;
clock-latency = <61036>; /* two CLK32 periods */
#cooling-cells = <2>;
cooling-min-level = <0>;
cooling-max-level = <2>;
};
cpu@1 {
compatible = "arm,cortex-a9";
reg = <1>;
next-level-cache = <&L2>;
};
cpu@2 {
compatible = "arm,cortex-a9";
reg = <2>;
next-level-cache = <&L2>;
};
cpu@3 {
compatible = "arm,cortex-a9";
reg = <3>;
next-level-cache = <&L2>;
};
};