cpufreq: cpu0: rename driver and internals to 'cpufreq_dt'

The naming convention of this driver was always under the scanner, people
complained that it should have a more generic name than cpu0, as it manages all
CPUs that are sharing clock lines.

Also, in future it will be modified to support any number of clusters with
separate clock/voltage lines.

Lets rename it to 'cpufreq_dt' from 'cpufreq_cpu0'.

Tested-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

1 files changed, 64 insertions, 0 deletions

diff --git a/Documentation/devicetree/bindings/cpufreq/cpufreq-dt.txt b/Documentation/devicetree/bindings/cpufreq/cpufreq-dt.txt
new file mode 100644
index 000000000000..e41c98ffbccb
--- /dev/null
+++ b/Documentation/devicetree/bindings/cpufreq/cpufreq-dt.txt
@@ -0,0 +1,64 @@
+Generic cpufreq driver
+
+It is a generic DT based cpufreq driver for 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>;
+	};
+};