Documentation: devicetree: add PPMU events description

Extend the documenation by events description with new 'event-data-type'
field. Add example how the event might be defined in DT.

Signed-off-by: Lukasz Luba <l.luba@partner.samsung.com>
Acked-by: Chanwoo Choi <cw00.choi@samsung.com>
Signed-off-by: Chanwoo Choi <cw00.choi@samsung.com>

diff --git a/Documentation/devicetree/bindings/devfreq/event/exynos-ppmu.txt b/Documentation/devicetree/bindings/devfreq/event/exynos-ppmu.txt
index 3e36c1d..fb46b49 100644 (file)
--- a/Documentation/devicetree/bindings/devfreq/event/exynos-ppmu.txt
+++ b/Documentation/devicetree/bindings/devfreq/event/exynos-ppmu.txt
@@ -10,14 +10,23 @@ The Exynos PPMU driver uses the devfreq-event class to provide event data
 to various devfreq devices. The devfreq devices would use the event data when
 derterming the current state of each IP.
 
 to various devfreq devices. The devfreq devices would use the event data when
 derterming the current state of each IP.
 

-Required properties:
+Required properties for PPMU device:

 - compatible: Should be "samsung,exynos-ppmu" or "samsung,exynos-ppmu-v2.
 - reg: physical base address of each PPMU and length of memory mapped region.
 
 - compatible: Should be "samsung,exynos-ppmu" or "samsung,exynos-ppmu-v2.
 - reg: physical base address of each PPMU and length of memory mapped region.
 

-Optional properties:
+Optional properties for PPMU device:

 - clock-names : the name of clock used by the PPMU, "ppmu"
 - clocks : phandles for clock specified in "clock-names" property
 
 - clock-names : the name of clock used by the PPMU, "ppmu"
 - clocks : phandles for clock specified in "clock-names" property
 

+Required properties for 'events' child node of PPMU device:
+- event-name : the unique event name among PPMU device
+Optional properties for 'events' child node of PPMU device:
+- event-data-type : Define the type of data which shell be counted
+by the counter. You can check include/dt-bindings/pmu/exynos_ppmu.h for
+all possible type, i.e. count read requests, count write data in bytes,
+etc. This field is optional and when it is missing, the driver code
+will use default data type.
+

 Example1 : PPMUv1 nodes in exynos3250.dtsi are listed below.
 
                ppmu_dmc0: ppmu_dmc0@106a0000 {
 Example1 : PPMUv1 nodes in exynos3250.dtsi are listed below.
 
                ppmu_dmc0: ppmu_dmc0@106a0000 {


@@ -145,3 +154,16 @@ Example3 : PPMUv2 nodes in exynos5433.dtsi are listed below.
                        reg = <0x104d0000 0x2000>;
                        status = "disabled";
                };
                        reg = <0x104d0000 0x2000>;
                        status = "disabled";
                };

+
+Example4 : 'event-data-type' in exynos4412-ppmu-common.dtsi are listed below.
+
+       &ppmu_dmc0 {
+               status = "okay";
+               events {
+                       ppmu_dmc0_3: ppmu-event3-dmc0 {
+                       event-name = "ppmu-event3-dmc0";
+                       event-data-type = <(PPMU_RO_DATA_CNT |
+                                       PPMU_WO_DATA_CNT)>;
+                       };
+               };
+       };