diff --git a/Documentation/devicetree/bindings/property-units.txt b/Documentation/devicetree/bindings/property-units.txt
index c80a110c1e26..218f99fa311f 100644
--- a/Documentation/devicetree/bindings/property-units.txt
+++ b/Documentation/devicetree/bindings/property-units.txt
@@ -17,6 +17,7 @@ Time/Frequency
 -ms		: millisecond
 -us		: microsecond
 -ns		: nanosecond
+-ps		: picosecond
 
 Distance
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