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authorAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-08-05 17:04:01 -0300
committerAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-08-05 17:04:01 -0300
commit57f0f512b273f60d52568b8c6b77e17f5636edc0 (patch)
tree5e910f0e82173f4ef4f51111366a3f1299037a7b /Documentation/devicetree/bindings/cpufreq
Initial import
Diffstat (limited to 'Documentation/devicetree/bindings/cpufreq')
-rw-r--r--Documentation/devicetree/bindings/cpufreq/arm_big_little_dt.txt65
-rw-r--r--Documentation/devicetree/bindings/cpufreq/cpufreq-dt.txt64
-rw-r--r--Documentation/devicetree/bindings/cpufreq/cpufreq-exynos5440.txt28
-rw-r--r--Documentation/devicetree/bindings/cpufreq/cpufreq-spear.txt42
4 files changed, 199 insertions, 0 deletions
diff --git a/Documentation/devicetree/bindings/cpufreq/arm_big_little_dt.txt b/Documentation/devicetree/bindings/cpufreq/arm_big_little_dt.txt
new file mode 100644
index 000000000..0715695e9
--- /dev/null
+++ b/Documentation/devicetree/bindings/cpufreq/arm_big_little_dt.txt
@@ -0,0 +1,65 @@
+Generic ARM big LITTLE cpufreq driver's DT glue
+-----------------------------------------------
+
+This is DT specific glue layer for generic cpufreq driver for big LITTLE
+systems.
+
+Both required and optional properties listed below must be defined
+under node /cpus/cpu@x. Where x is the first cpu inside a cluster.
+
+FIXME: Cpus should boot in the order specified in DT and all cpus for a cluster
+must be present contiguously. Generic DT driver will check only node 'x' for
+cpu:x.
+
+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.
+
+Examples:
+
+cpus {
+ #address-cells = <1>;
+ #size-cells = <0>;
+
+ cpu@0 {
+ compatible = "arm,cortex-a15";
+ reg = <0>;
+ next-level-cache = <&L2>;
+ operating-points = <
+ /* kHz uV */
+ 792000 1100000
+ 396000 950000
+ 198000 850000
+ >;
+ clock-latency = <61036>; /* two CLK32 periods */
+ };
+
+ cpu@1 {
+ compatible = "arm,cortex-a15";
+ reg = <1>;
+ next-level-cache = <&L2>;
+ };
+
+ cpu@100 {
+ compatible = "arm,cortex-a7";
+ reg = <100>;
+ next-level-cache = <&L2>;
+ operating-points = <
+ /* kHz uV */
+ 792000 950000
+ 396000 750000
+ 198000 450000
+ >;
+ clock-latency = <61036>; /* two CLK32 periods */
+ };
+
+ cpu@101 {
+ compatible = "arm,cortex-a7";
+ reg = <101>;
+ next-level-cache = <&L2>;
+ };
+};
diff --git a/Documentation/devicetree/bindings/cpufreq/cpufreq-dt.txt b/Documentation/devicetree/bindings/cpufreq/cpufreq-dt.txt
new file mode 100644
index 000000000..e41c98ffb
--- /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>;
+ };
+};
diff --git a/Documentation/devicetree/bindings/cpufreq/cpufreq-exynos5440.txt b/Documentation/devicetree/bindings/cpufreq/cpufreq-exynos5440.txt
new file mode 100644
index 000000000..caff1a574
--- /dev/null
+++ b/Documentation/devicetree/bindings/cpufreq/cpufreq-exynos5440.txt
@@ -0,0 +1,28 @@
+
+Exynos5440 cpufreq driver
+-------------------
+
+Exynos5440 SoC cpufreq driver for CPU frequency scaling.
+
+Required properties:
+- interrupts: Interrupt to know the completion of cpu frequency change.
+- operating-points: Table of frequencies and voltage CPU could be transitioned into,
+ in the decreasing order. Frequency should be in KHz units and voltage
+ should be in microvolts.
+
+Optional properties:
+- clock-latency: Clock monitor latency in microsecond.
+
+All the required listed above must be defined under node cpufreq.
+
+Example:
+--------
+ cpufreq@160000 {
+ compatible = "samsung,exynos5440-cpufreq";
+ reg = <0x160000 0x1000>;
+ interrupts = <0 57 0>;
+ operating-points = <
+ 1000000 975000
+ 800000 925000>;
+ clock-latency = <100000>;
+ };
diff --git a/Documentation/devicetree/bindings/cpufreq/cpufreq-spear.txt b/Documentation/devicetree/bindings/cpufreq/cpufreq-spear.txt
new file mode 100644
index 000000000..f3d44984d
--- /dev/null
+++ b/Documentation/devicetree/bindings/cpufreq/cpufreq-spear.txt
@@ -0,0 +1,42 @@
+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 >;
+ };
+
+ <...>
+
+};