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-rw-r--r--Documentation/devicetree/bindings/cpufreq/cpufreq-cpu0.txt55
-rw-r--r--Documentation/devicetree/bindings/cpufreq/cpufreq-spear.txt42
2 files changed, 97 insertions, 0 deletions
diff --git a/Documentation/devicetree/bindings/cpufreq/cpufreq-cpu0.txt b/Documentation/devicetree/bindings/cpufreq/cpufreq-cpu0.txt
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index 00000000000..4416ccc3347
--- /dev/null
+++ b/Documentation/devicetree/bindings/cpufreq/cpufreq-cpu0.txt
@@ -0,0 +1,55 @@
+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:
+- operating-points: Refer to Documentation/devicetree/bindings/power/opp.txt
+ for details
+
+Optional properties:
+- clock-latency: Specify the possible maximum transition latency for clock,
+ in unit of nanoseconds.
+- voltage-tolerance: Specify the CPU voltage tolerance in percentage.
+
+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
+ >;
+ transition-latency = <61036>; /* two CLK32 periods */
+ };
+
+ 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>;
+ };
+};
diff --git a/Documentation/devicetree/bindings/cpufreq/cpufreq-spear.txt b/Documentation/devicetree/bindings/cpufreq/cpufreq-spear.txt
new file mode 100644
index 00000000000..f3d44984d91
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+++ b/Documentation/devicetree/bindings/cpufreq/cpufreq-spear.txt
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+SPEAr cpufreq driver
+-------------------
+
+SPEAr SoC cpufreq driver for CPU frequency scaling.
+It supports both uniprocessor (UP) and symmetric multiprocessor (SMP) systems
+which share clock across all CPUs.
+
+Required properties:
+- cpufreq_tbl: Table of frequencies CPU could be transitioned into, in the
+ increasing order.
+
+Optional properties:
+- clock-latency: Specify the possible maximum transition latency for clock, in
+ unit of nanoseconds.
+
+Both required and optional properties listed above must be defined under node
+/cpus/cpu@0.
+
+Examples:
+--------
+cpus {
+
+ <...>
+
+ cpu@0 {
+ compatible = "arm,cortex-a9";
+ reg = <0>;
+
+ <...>
+
+ cpufreq_tbl = < 166000
+ 200000
+ 250000
+ 300000
+ 400000
+ 500000
+ 600000 >;
+ };
+
+ <...>
+
+};