[PATCH 1/5] dt-bindings: iommu: arm,smmu-v3: allow a power domain

[Arun Iyengar via B4 Relay]

From: Arun Iyengar <aiyengar1990@xxxxxxxxx>

An SMMUv3 instance can sit in a switchable power domain of the SoC, for
example the MMU-600 in front of the PCIe controllers on the Rockchip
RK3588, which is part of the PCIe power domain. If the domain is not
described, nothing keeps it powered while the SMMU is bound, and any
register access after it has been turned off as unused stalls the
interconnect.

Allow a single power-domains entry, as arm,smmu.yaml already does for
the earlier SMMU architectures.

Signed-off-by: Arun Iyengar <aiyengar1990@xxxxxxxxx>
---
 Documentation/devicetree/bindings/iommu/arm,smmu-v3.yaml | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/Documentation/devicetree/bindings/iommu/arm,smmu-v3.yaml b/Documentation/devicetree/bindings/iommu/arm,smmu-v3.yaml
index 3c044e4f03d4..c8f22dfdb1db 100644
--- a/Documentation/devicetree/bindings/iommu/arm,smmu-v3.yaml
+++ b/Documentation/devicetree/bindings/iommu/arm,smmu-v3.yaml
@@ -63,6 +63,9 @@ properties:
 
   msi-parent: true
 
+  power-domains:
+    maxItems: 1
+
   nvidia,cmdqv:
     description: |
       A phandle to its pairing CMDQV extension for an implementation on NVIDIA

-- 
2.55.0