[v2,3/4] dt-bindings: add binding document for Rockchip cpu avs

Commit Message

Finley Xiao Aug. 18, 2016, 8:52 a.m. UTC

From: Finley Xiao <[e-mail]>

This patch documents the Rockchip cpu avs device tree binding.

Signed-off-by: Finley Xiao <[e-mail]>
---
 .../devicetree/bindings/power/rockchip-cpu-avs.txt | 37 ++++++++++++++++++++++
 1 file changed, 37 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/power/rockchip-cpu-avs.txt

Patch

diff --git a/Documentation/devicetree/bindings/power/rockchip-cpu-avs.txt b/Documentation/devicetree/bindings/power/rockchip-cpu-avs.txt
new file mode 100644
index 0000000..705f516
--- /dev/null
+++ b/Documentation/devicetree/bindings/power/rockchip-cpu-avs.txt
@@ -0,0 +1,37 @@ 
+Rockchip cpu avs device tree bindings
+-------------------------------------
+
+Under the same frequency, the operating voltage tends to decrease with
+increasing leakage. so it is necessary to adjust opp's voltage according
+to leakage for power.
+
+
+Required properties:
+- compatible: Should be one of the following.
+  - "rockchip,rk3399-cpu-avs" - for RK3399 SoCs.
+- leakage-volt-<name>: Named leakage-volt property. At runtime, the
+  platform can find a cpu's cluster_id according to it's cpu_id and match
+  leakage-volt-<name> property. The property is an array of 3-tuples
+  items, and each item consists of leakage and voltage like
+  <min-leakage-mA max-leakage-mA volt-uV>.
+	min-leakage: minimum leakage in mA, ranges from 0 to 254.
+	max-leakage: maximum leakage in mA, ranges from 0 to 254.
+	volt: voltage offset in mV to apply to the opp table entries.
+
+Example:
+
+	cpu_avs: cpu-avs {
+		compatible = "rockchip,rk3399-cpu-avs";
+		leakage-volt-cluster0 = <
+		/*  mA        mA         uV*/
+		    0         100        0
+		    101       200        (-25000)
+		    201       254        (-50000)
+		>;
+		leakage-volt-cluster1 = <
+		/*  mA        mA         uV*/
+		    0         100        0
+		    101       200        (-25000)
+		    201       254        (-50000)
+		>;
+	};