1 files changed, 15 insertions, 0 deletions

diff --git a/Documentation/ABI/testing/sysfs-devices-system-cpu b/Documentation/ABI/testing/sysfs-devices-system-cpu
index 2447698aed41..468e4d48f884 100644
--- a/Documentation/ABI/testing/sysfs-devices-system-cpu
+++ b/Documentation/ABI/testing/sysfs-devices-system-cpu
@@ -144,6 +144,21 @@ Description:	Discover and change clock speed of CPUs
                 to learn how to control the knobs.
 
 
+What:           /sys/devices/system/cpu/cpu#/cpufreq/freqdomain_cpus
+Date:           June 2013
+Contact:        cpufreq@vger.kernel.org
+Description:    Discover CPUs in the same CPU frequency coordination domain
+
+                freqdomain_cpus is the list of CPUs (online+offline) that share
+                the same clock/freq domain (possibly at the hardware level).
+                That information may be hidden from the cpufreq core and the
+                value of related_cpus may be different from freqdomain_cpus. This
+                attribute is useful for user space DVFS controllers to get better
+                power/performance results for platforms using acpi-cpufreq.
+
+                This file is only present if the acpi-cpufreq driver is in use.
+
+
 What:           /sys/devices/system/cpu/cpu*/cache/index3/cache_disable_{0,1}
 Date:           August 2008
 KernelVersion:  2.6.27