diff --git a/Documentation/devicetree/bindings/iommu/rockchip,iommu.txt b/Documentation/devicetree/bindings/iommu/rockchip,iommu.txt
index 9e315158dadd..269264a6ec47 100644
--- a/Documentation/devicetree/bindings/iommu/rockchip,iommu.txt
+++ b/Documentation/devicetree/bindings/iommu/rockchip,iommu.txt
@@ -22,6 +22,15 @@ Required properties:
                     to associate with its master device.  See:
                     Documentation/devicetree/bindings/iommu/iommu.txt
 
+Optional properties:
+- rockchip,disable-mmu-reset 	: Don't use the mmu reset operation.
+				  Some mmu instances may produce unexpected results
+				  when the reset operation is used.
+- rk_iommu,disable_reset_quirk  : Same with above, for compatible with previous code
+
+- rockchip,skip-mmu-read 	: Some iommu instances are not able to be read, skip
+				  reading operation to make iommu work as normal
+
 Example:
 
 	vopl_mmu: iommu@ff8f3f00 {