Documentation: add ABI entry for intel_pstate

Add a Documentation/ABI entry for
/sys/devices/system/cpu/intel_pstate/max_perf_pct,
/sys/devices/system/cpu/intel_pstate/min_perf_pct, and
/sys/devices/system/cpu/intel_pstate/no_turbo.

Cc: Dirk Brandewie <dirk.brandewie@gmail.com>
Cc: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Ramkumar Ramachandra <artagnon@gmail.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

1 files changed, 24 insertions, 0 deletions

diff --git a/Documentation/ABI/testing/sysfs-devices-system-cpu b/Documentation/ABI/testing/sysfs-devices-system-cpu
index 468e4d48f884..d5a0d33c571f 100644
--- a/Documentation/ABI/testing/sysfs-devices-system-cpu
+++ b/Documentation/ABI/testing/sysfs-devices-system-cpu
@@ -200,3 +200,27 @@ Description:	address and size of the percpu note.
                 note of cpu#.
 
                 crash_notes_size: size of the note of cpu#.
+
+
+What:           /sys/devices/system/cpu/intel_pstate/max_perf_pct
+                /sys/devices/system/cpu/intel_pstate/min_perf_pct
+                /sys/devices/system/cpu/intel_pstate/no_turbo
+Date:           February 2013
+Contact:        linux-pm@vger.kernel.org
+Description:    Parameters for the Intel P-state driver
+
+                Logic for selecting the current P-state in Intel
+                Sandybridge+ processors. The three knobs control
+                limits for the P-state that will be requested by the
+                driver.
+
+                max_perf_pct: limits the maximum P state that will be requested by
+                the driver stated as a percentage of the available performance.
+
+                min_perf_pct: limits the minimum P state that will be requested by
+                the driver stated as a percentage of the available performance.
+
+                no_turbo: limits the driver to selecting P states below the turbo
+                frequency range.
+
+                More details can be found in Documentation/cpu-freq/intel-pstate.txt