diff --git a/Documentation/devicetree/bindings/mailbox/omap-mailbox.txt b/Documentation/devicetree/bindings/mailbox/omap-mailbox.txt
index 0ef372656a3eac86e8b1be97fc7dc8231936b8e2..35c3f56b7f7bf56b7a2485addbf8140a441cc85a 100644
--- a/Documentation/devicetree/bindings/mailbox/omap-mailbox.txt
+++ b/Documentation/devicetree/bindings/mailbox/omap-mailbox.txt
@@ -1,4 +1,4 @@
-OMAP2+ Mailbox Driver
+OMAP2+ and K3 Mailbox
 =====================
 
 The OMAP mailbox hardware facilitates communication between different processors
@@ -7,7 +7,7 @@ various processor subsystems and is connected on an interconnect bus. The
 communication is achieved through a set of registers for message storage and
 interrupt configuration registers.
 
-Each mailbox IP block has a certain number of h/w fifo queues and output
+Each mailbox IP block/cluster has a certain number of h/w fifo queues and output
 interrupt lines. An output interrupt line is routed to an interrupt controller
 within a processor subsystem, and there can be more than one line going to a
 specific processor's interrupt controller. The interrupt line connections are
@@ -23,12 +23,16 @@ All the current OMAP SoCs except for the newest DRA7xx SoC has a single IP
 instance. DRA7xx has multiple instances with different number of h/w fifo queues
 and interrupt lines between different instances. The interrupt lines can also be
 routed to different processor sub-systems on DRA7xx as they are routed through
-the Crossbar, a kind of interrupt router/multiplexer.
+the Crossbar, a kind of interrupt router/multiplexer. The K3 AM65x and J721E
+SoCs has each of these instances form a cluster and combine multiple clusters
+into a single IP block present within the Main NavSS. The interrupt lines from
+all these clusters are multiplexed and routed to different processor subsystems
+over a limited number of common interrupt output lines of an Interrupt Router.
 
 Mailbox Device Node:
 ====================
-A Mailbox device node is used to represent a Mailbox IP instance within a SoC.
-The sub-mailboxes are represented as child nodes of this parent node.
+A Mailbox device node is used to represent a Mailbox IP instance/cluster within
+a SoC. The sub-mailboxes are represented as child nodes of this parent node.
 
 Required properties:
 --------------------
@@ -37,12 +41,12 @@ Required properties:
 			    "ti,omap3-mailbox" for OMAP3430, OMAP3630 SoCs
 			    "ti,omap4-mailbox" for OMAP44xx, OMAP54xx, AM33xx,
 						   AM43xx and DRA7xx SoCs
+			    "ti,am654-mailbox" for K3 AM65x and J721E SoCs
 - reg:			Contains the mailbox register address range (base
 			address and length)
 - interrupts:		Contains the interrupt information for the mailbox
 			device. The format is dependent on which interrupt
-			controller the OMAP device uses
-- ti,hwmods:		Name of the hwmod associated with the mailbox
+			controller the Mailbox device uses
 - #mbox-cells:		Common mailbox binding property to identify the number
 			of cells required for the mailbox specifier. Should be
 			1
@@ -50,6 +54,23 @@ Required properties:
 			device can interrupt
 - ti,mbox-num-fifos:	Number of h/w fifo queues within the mailbox IP block
 
+SoC-specific Required properties:
+---------------------------------
+The following are mandatory properties for the OMAP architecture based SoCs
+only:
+- ti,hwmods:		Name of the hwmod associated with the mailbox. This
+			should be defined in the mailbox node only if the node
+			is not defined as a child node of a corresponding sysc
+			interconnect node.
+
+The following are mandatory properties for the K3 AM65x and J721E SoCs only:
+- interrupt-parent:	Should contain a phandle to the TI-SCI interrupt
+			controller node that is used to dynamically program
+			the interrupt routes between the IP and the main GIC
+			controllers. See the following binding for additional
+			details,
+			Documentation/devicetree/bindings/interrupt-controller/ti,sci-intr.txt
+
 Child Nodes:
 ============
 A child node is used for representing the actual sub-mailbox device that is
@@ -98,7 +119,7 @@ to be used by the client user.
 Example:
 --------
 
-/* OMAP4 */
+1. /* OMAP4 */
 mailbox: mailbox@4a0f4000 {
 	compatible = "ti,omap4-mailbox";
 	reg = <0x4a0f4000 0x200>;
@@ -123,7 +144,7 @@ dsp {
 	...
 };
 
-/* AM33xx */
+2. /* AM33xx */
 mailbox: mailbox@480c8000 {
 	compatible = "ti,omap4-mailbox";
 	reg = <0x480C8000 0x200>;
@@ -137,3 +158,23 @@ mailbox: mailbox@480c8000 {
 		ti,mbox-rx = <0 0 3>;
 	};
 };
+
+3. /* AM65x */
+&cbass_main {
+	cbass_main_navss: interconnect0 {
+		mailbox0_cluster0: mailbox@31f80000 {
+			compatible = "ti,am654-mailbox";
+			reg = <0x00 0x31f80000 0x00 0x200>;
+			#mbox-cells = <1>;
+			ti,mbox-num-users = <4>;
+			ti,mbox-num-fifos = <16>;
+			interrupt-parent = <&intr_main_navss>;
+			interrupts = <164 0>;
+
+			mbox_mcu_r5fss0_core0: mbox-mcu-r5fss0-core0 {
+				ti,mbox-tx = <1 0 0>;
+				ti,mbox-rx = <0 0 0>;
+			};
+		};
+	};
+};