arm64: dts: ti: k3-am65-main: Add mailbox cluster nodes

The AM65x Main NavSS block contains a Mailbox IP instance with
multiple clusters. Each cluster is equivalent to an Mailbox IP
instance on OMAP platforms.

Add all the Mailbox clusters as their own nodes under the MAIN
NavSS cbass_main_navss interconnect node instead of creating an
almost empty parent node for the new K3 mailbox IP and the clusters
as its child nodes. All these nodes are enabled by default in the
base dtsi file, but any cluster that does not define any child
sub-mailbox nodes should be disabled in the corresponding board
dts files.

NOTE:
The NavSS only has a limited number of interrupts, so none of the
interrupts generated by a Mailbox IP are added by default. Only
the needed interrupts that are targeted towards the A53 GIC will
have to be added later on in the board dts files alongside the
corresponding sub-mailbox child nodes.

Signed-off-by: Suman Anna <s-anna@ti.com>
Signed-off-by: Tero Kristo <t-kristo@ti.com>

arch/arm64/boot/dts/ti/k3-am65-main.dtsi

@@ -419,6 +419,114 @@
 			reg = <0x00 0x30e00000 0x00 0x1000>;
 			#hwlock-cells = <1>;
 		};
+
+		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>;
+		};
+
+		mailbox0_cluster1: mailbox@31f81000 {
+			compatible = "ti,am654-mailbox";
+			reg = <0x00 0x31f81000 0x00 0x200>;
+			#mbox-cells = <1>;
+			ti,mbox-num-users = <4>;
+			ti,mbox-num-fifos = <16>;
+			interrupt-parent = <&intr_main_navss>;
+		};
+
+		mailbox0_cluster2: mailbox@31f82000 {
+			compatible = "ti,am654-mailbox";
+			reg = <0x00 0x31f82000 0x00 0x200>;
+			#mbox-cells = <1>;
+			ti,mbox-num-users = <4>;
+			ti,mbox-num-fifos = <16>;
+			interrupt-parent = <&intr_main_navss>;
+		};
+
+		mailbox0_cluster3: mailbox@31f83000 {
+			compatible = "ti,am654-mailbox";
+			reg = <0x00 0x31f83000 0x00 0x200>;
+			#mbox-cells = <1>;
+			ti,mbox-num-users = <4>;
+			ti,mbox-num-fifos = <16>;
+			interrupt-parent = <&intr_main_navss>;
+		};
+
+		mailbox0_cluster4: mailbox@31f84000 {
+			compatible = "ti,am654-mailbox";
+			reg = <0x00 0x31f84000 0x00 0x200>;
+			#mbox-cells = <1>;
+			ti,mbox-num-users = <4>;
+			ti,mbox-num-fifos = <16>;
+			interrupt-parent = <&intr_main_navss>;
+		};
+
+		mailbox0_cluster5: mailbox@31f85000 {
+			compatible = "ti,am654-mailbox";
+			reg = <0x00 0x31f85000 0x00 0x200>;
+			#mbox-cells = <1>;
+			ti,mbox-num-users = <4>;
+			ti,mbox-num-fifos = <16>;
+			interrupt-parent = <&intr_main_navss>;
+		};
+
+		mailbox0_cluster6: mailbox@31f86000 {
+			compatible = "ti,am654-mailbox";
+			reg = <0x00 0x31f86000 0x00 0x200>;
+			#mbox-cells = <1>;
+			ti,mbox-num-users = <4>;
+			ti,mbox-num-fifos = <16>;
+			interrupt-parent = <&intr_main_navss>;
+		};
+
+		mailbox0_cluster7: mailbox@31f87000 {
+			compatible = "ti,am654-mailbox";
+			reg = <0x00 0x31f87000 0x00 0x200>;
+			#mbox-cells = <1>;
+			ti,mbox-num-users = <4>;
+			ti,mbox-num-fifos = <16>;
+			interrupt-parent = <&intr_main_navss>;
+		};
+
+		mailbox0_cluster8: mailbox@31f88000 {
+			compatible = "ti,am654-mailbox";
+			reg = <0x00 0x31f88000 0x00 0x200>;
+			#mbox-cells = <1>;
+			ti,mbox-num-users = <4>;
+			ti,mbox-num-fifos = <16>;
+			interrupt-parent = <&intr_main_navss>;
+		};
+
+		mailbox0_cluster9: mailbox@31f89000 {
+			compatible = "ti,am654-mailbox";
+			reg = <0x00 0x31f89000 0x00 0x200>;
+			#mbox-cells = <1>;
+			ti,mbox-num-users = <4>;
+			ti,mbox-num-fifos = <16>;
+			interrupt-parent = <&intr_main_navss>;
+		};
+
+		mailbox0_cluster10: mailbox@31f8a000 {
+			compatible = "ti,am654-mailbox";
+			reg = <0x00 0x31f8a000 0x00 0x200>;
+			#mbox-cells = <1>;
+			ti,mbox-num-users = <4>;
+			ti,mbox-num-fifos = <16>;
+			interrupt-parent = <&intr_main_navss>;
+		};
+
+		mailbox0_cluster11: mailbox@31f8b000 {
+			compatible = "ti,am654-mailbox";
+			reg = <0x00 0x31f8b000 0x00 0x200>;
+			#mbox-cells = <1>;
+			ti,mbox-num-users = <4>;
+			ti,mbox-num-fifos = <16>;
+			interrupt-parent = <&intr_main_navss>;
+		};
 	};
 
 	main_gpio0:  main_gpio0@600000 {