[PATCH v3] dt-bindings: arm: keystone: add boot_* mboxes to ti,sci

[Anshul Dalal <anshuld@ti.com>]

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>
---
Changes in v3:
- Drop [1/2] of the last patch series
- Update existing example with boot_* mailboxes instead of adding a new one
- Link to v2: https://lore.kernel.org/r/20251112-k3_syscon_add_boot_mailboxes-v2-0-aebc1e47b391@ti.com

Changes in v2:
- Remove maxItems entry
- Remove RFC tag from patch (added by mistake in v1)
- Document the new mailboxes in mboxes instead of mbox-names
- Provide example with all the mailboxes set
- Update commit title to have "ti,sci"
- Split into two patches
- Link to v1: https://lore.kernel.org/r/20251111-k3_syscon_add_boot_mailboxes-v1-1-529a27f21076@ti.com
---
 .../devicetree/bindings/arm/keystone/ti,sci.yaml      | 19 ++++++++++++++++---
 1 file changed, 16 insertions(+), 3 deletions(-)

diff --git a/Documentation/devicetree/bindings/arm/keystone/ti,sci.yaml b/Documentation/devicetree/bindings/arm/keystone/ti,sci.yaml
index 25a2b42105e541cb3c8ad12a0dfec1af038fa907..be8a5b2b051b441884795059c70892910d981130 100644
--- a/Documentation/devicetree/bindings/arm/keystone/ti,sci.yaml
+++ b/Documentation/devicetree/bindings/arm/keystone/ti,sci.yaml
@@ -51,15 +51,27 @@ 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
+    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
@@ -90,9 +102,10 @@ examples:
   - |
     pmmc: system-controller@2921800 {
       compatible = "ti,k2g-sci";
-      mbox-names = "rx", "tx";
-      mboxes = <&msgmgr 5 2>,
-               <&msgmgr 0 0>;
+      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 = <0x02921800 0x800>;
     };

---
base-commit: 4427259cc7f7571a157fbc9b5011e1ef6fe0a4a8
change-id: 20251105-k3_syscon_add_boot_mailboxes-8452bdd98962

Best regards,
-- 
Anshul Dalal <anshuld@ti.com>