[RFC PATCH 1/8] dt-bindings: iommu: mediatek: Add mt8196 support

[Xueqi Zhang]

1. Mediatek has its own implementation for wrapper interrupts and
power management. Add the SoC specific compatible for MT8196
implementing arm,smmu-v3.
2. APU SMMU need wait until its power is ready, thus add a phandle
smmu-mediatek-parents to its power node.

Signed-off-by: Xueqi Zhang <xueqi.zhang at mediatek.com>
---
 .../bindings/iommu/arm,smmu-v3.yaml           | 24 ++++++++++++++++++-
 1 file changed, 23 insertions(+), 1 deletion(-)

diff --git a/Documentation/devicetree/bindings/iommu/arm,smmu-v3.yaml b/Documentation/devicetree/bindings/iommu/arm,smmu-v3.yaml
index 75fcf4cb52d9..c9a99e54de69 100644
--- a/Documentation/devicetree/bindings/iommu/arm,smmu-v3.yaml
+++ b/Documentation/devicetree/bindings/iommu/arm,smmu-v3.yaml
@@ -20,7 +20,12 @@ properties:
   $nodename:
     pattern: "^iommu@[0-9a-f]*"
   compatible:
-    const: arm,smmu-v3
+    - description: MediaTek SoCs implementing "arm,smmu-v3"
+      items:
+        - enum:
+            - mediatek,mt8196-apu-smmu
+            - mediatek,mt8196-mm-smmu
+        - const: arm,smmu-v3
 
   reg:
     maxItems: 1
@@ -69,11 +74,28 @@ properties:
       register access with page 0 offsets. Set for Cavium ThunderX2 silicon that
       doesn't support SMMU page1 register space.
 
+  mediatek,smmu-parents:
+    $ref: /schemas/types.yaml#/definitions/phandle
+    description:
+      A phandle to the SMMU's power node. The SMMU should wait until its power
+      is ready
+
 required:
   - compatible
   - reg
   - '#iommu-cells'
 
+allOf:
+  - if:  # for SMMU need to wait its power node
+      properties:
+        compatible:
+          contains:
+            enum:
+              - mediatek,mt8196-apu-smmu
+    then:
+      required:
+        - mediatek,smmu-parents
+
 additionalProperties: false
 
 examples:
-- 
2.46.0