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-rw-r--r--Documentation/cpu-freq/cpu-drivers.txt6
-rw-r--r--Documentation/cpu-freq/user-guide.txt8
-rw-r--r--Documentation/devicetree/bindings/arm/kirkwood.txt27
3 files changed, 37 insertions, 4 deletions
diff --git a/Documentation/cpu-freq/cpu-drivers.txt b/Documentation/cpu-freq/cpu-drivers.txt
index c436096351f..72f70b16d29 100644
--- a/Documentation/cpu-freq/cpu-drivers.txt
+++ b/Documentation/cpu-freq/cpu-drivers.txt
@@ -111,6 +111,12 @@ policy->governor must contain the "default policy" for
For setting some of these values, the frequency table helpers might be
helpful. See the section 2 for more information on them.
+SMP systems normally have same clock source for a group of cpus. For these the
+.init() would be called only once for the first online cpu. Here the .init()
+routine must initialize policy->cpus with mask of all possible cpus (Online +
+Offline) that share the clock. Then the core would copy this mask onto
+policy->related_cpus and will reset policy->cpus to carry only online cpus.
+
1.3 verify
------------
diff --git a/Documentation/cpu-freq/user-guide.txt b/Documentation/cpu-freq/user-guide.txt
index 04f6b32993e..ff2f28332cc 100644
--- a/Documentation/cpu-freq/user-guide.txt
+++ b/Documentation/cpu-freq/user-guide.txt
@@ -190,11 +190,11 @@ scaling_max_freq show the current "policy limits" (in
first set scaling_max_freq, then
scaling_min_freq.
-affected_cpus : List of CPUs that require software coordination
- of frequency.
+affected_cpus : List of Online CPUs that require software
+ coordination of frequency.
-related_cpus : List of CPUs that need some sort of frequency
- coordination, whether software or hardware.
+related_cpus : List of Online + Offline CPUs that need software
+ coordination of frequency.
scaling_driver : Hardware driver for cpufreq.
diff --git a/Documentation/devicetree/bindings/arm/kirkwood.txt b/Documentation/devicetree/bindings/arm/kirkwood.txt
new file mode 100644
index 00000000000..98cce9a653e
--- /dev/null
+++ b/Documentation/devicetree/bindings/arm/kirkwood.txt
@@ -0,0 +1,27 @@
+Marvell Kirkwood Platforms Device Tree Bindings
+-----------------------------------------------
+
+Boards with a SoC of the Marvell Kirkwood
+shall have the following property:
+
+Required root node property:
+
+compatible: must contain "marvell,kirkwood";
+
+In order to support the kirkwood cpufreq driver, there must be a node
+cpus/cpu@0 with three clocks, "cpu_clk", "ddrclk" and "powersave",
+where the "powersave" clock is a gating clock used to switch the CPU
+between the "cpu_clk" and the "ddrclk".
+
+Example:
+
+ cpus {
+ #address-cells = <1>;
+ #size-cells = <0>;
+
+ cpu@0 {
+ device_type = "cpu";
+ compatible = "marvell,sheeva-88SV131";
+ clocks = <&core_clk 1>, <&core_clk 3>, <&gate_clk 11>;
+ clock-names = "cpu_clk", "ddrclk", "powersave";
+ };