Documentation: bindings: add dt documentation for dfi controller

This patch adds the documentation for rockchip dfi devfreq-event driver.

Signed-off-by: Lin Huang <hl@rock-chips.com>
Acked-by: Chanwoo Choi <cw00.choi@samsung.com>
Signed-off-by: MyungJoo Ham <myungjoo.ham@samsung.com>

diff --git a/Documentation/devicetree/bindings/devfreq/event/rockchip-dfi.txt b/Documentation/devicetree/bindings/devfreq/event/rockchip-dfi.txt
new file mode 100644 (file)
index 0000000..f223313
--- /dev/null
+++ b/Documentation/devicetree/bindings/devfreq/event/rockchip-dfi.txt
@@ -0,0 +1,19 @@
+
+* Rockchip rk3399 DFI device
+
+Required properties:
+- compatible: Must be "rockchip,rk3399-dfi".
+- reg: physical base address of each DFI and length of memory mapped region
+- rockchip,pmu: phandle to the syscon managing the "pmu general register files"
+- clocks: phandles for clock specified in "clock-names" property
+- clock-names : the name of clock used by the DFI, must be "pclk_ddr_mon";
+
+Example:
+       dfi: dfi@0xff630000 {
+               compatible = "rockchip,rk3399-dfi";
+               reg = <0x00 0xff630000 0x00 0x4000>;
+               rockchip,pmu = <&pmugrf>;
+               clocks = <&cru PCLK_DDR_MON>;
+               clock-names = "pclk_ddr_mon";
+               status = "disabled";
+       };