powerpc/perf/hv-24x7: Document sysfs event description entries

Signed-off-by: Cody P Schafer <cody@linux.vnet.ibm.com>
Signed-off-by: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

Documentation/ABI/testing/sysfs-bus-event_source-devices-hv_24x7

@@ -21,3 +21,25 @@ Contact:	Linux on PowerPC Developer List <linuxppc-dev@lists.ozlabs.org>
 Description:
 		Exposes the "version" field of the 24x7 catalog. This is also
 		extractable from the provided binary "catalog" sysfs entry.
+
+What:		/sys/bus/event_source/devices/hv_24x7/event_descs/<event-name>
+Date:		February 2014
+Contact:	Linux on PowerPC Developer List <linuxppc-dev@lists.ozlabs.org>
+Description:
+		Provides the description of a particular event as provided by
+		the firmware. If firmware does not provide a description, no
+		file will be created.
+
+		Note that the event-name lacks the domain suffix appended for
+		events in the events/ dir.
+
+What:		/sys/bus/event_source/devices/hv_24x7/event_long_descs/<event-name>
+Date:		February 2014
+Contact:	Linux on PowerPC Developer List <linuxppc-dev@lists.ozlabs.org>
+Description:
+		Provides the "long" description of a particular event as
+		provided by the firmware. If firmware does not provide a
+		description, no file will be created.
+
+		Note that the event-name lacks the domain suffix appended for
+		events in the events/ dir.