The bootloader on K3 devices makes use of mailboxes as per the ROM spec
which might be different than one's available to the kernel (firmware
spec).

Therefore, this patch adds the missing mailbox entries to the DT binding
to represent the mailboxes exposed by the hardware during boot for the
purpose of loading the firmware.

Signed-off-by: Anshul Dalal <anshuld@ti.com>
---
 .../devicetree/bindings/arm/keystone/ti,sci.yaml     | 20 ++++++++++++++++++++
 1 file changed, 20 insertions(+)

diff --git a/Documentation/devicetree/bindings/arm/keystone/ti,sci.yaml b/Documentation/devicetree/bindings/arm/keystone/ti,sci.yaml
index 182915c34fc1429fb627ac44c99c0c76fdf28e0f..770d6bc7c8f83493e448c426cb8f785dd73e824d 100644
--- a/Documentation/devicetree/bindings/arm/keystone/ti,sci.yaml
+++ b/Documentation/devicetree/bindings/arm/keystone/ti,sci.yaml
@@ -51,12 +51,17 @@ properties:
     minItems: 1
 
   mbox-names:
+    minItems: 2
     description: |
       Specifies the mailboxes used to communicate with TI-SCI Controller
       made available from TI-SCI controller.
     items:
       - const: rx
       - const: tx
+      - const: notify
+      - const: boot_rx
+      - const: boot_tx
+      - const: boot_notify
 
   mboxes:
     minItems: 2
@@ -66,6 +71,10 @@ properties:
     items:
       - description: RX thread
       - description: TX thread
+      - description: Notify thread
+      - description: boot stage RX thread
+      - description: boot stage TX thread
+      - description: boot stage Notify thread
 
   ti,host-id:
     $ref: /schemas/types.yaml#/definitions/uint32
@@ -128,3 +137,14 @@ examples:
         #reset-cells = <2>;
       };
     };
+
+  - |
+    sms: system-controller@44083000 {
+      compatible = "ti,am654-sci";
+      mbox-names = "rx", "tx", "notify", "boot_rx", "boot_tx", "boot_notify";
+      mboxes = <&secure_proxy_mcu 8>, <&secure_proxy_mcu 6>,
+        <&secure_proxy_mcu 5>, <&secure_proxy_mcu 4>,
+        <&secure_proxy_mcu 5>, <&secure_proxy_sa3 5>;
+      reg-names = "debug_messages";
+      reg = <0x44083000 0x1000>;
+    };

-- 
2.51.0

On 12/11/2025 09:30, Anshul Dalal wrote:
>    ti,host-id:
>      $ref: /schemas/types.yaml#/definitions/uint32
> @@ -128,3 +137,14 @@ examples:
>          #reset-cells = <2>;
>        };
>      };
> +
> +  - |
> +    sms: system-controller@44083000 {
> +      compatible = "ti,am654-sci";

I asked to update the example. THE example, existing example, not adding
new example or examples.

You claim in this patch that EVERY device has 6 mailboxes, so I do not
understand why you need new example.

Best regards,
Krzysztof