[PATCH v4 01/10] dt-bindings: iommu: Add Translation Buffer Unit bindings

[Georgi Djakov <quic_c_gdjako@xxxxxxxxxxx>]

Add common bindings for the TBUs to describe their properties. The
TBUs are modelled as child devices of the IOMMU and each of them is
described with their compatible, reg and stream-id-range properties.
There could be other implementation specific properties to describe
any resources like clocks, regulators, power-domains, interconnects
that would be needed for TBU operation. Such properties will be
documented in a separate vendor-specific TBU schema.

Signed-off-by: Georgi Djakov <quic_c_gdjako@xxxxxxxxxxx>
---
 .../devicetree/bindings/iommu/arm,smmu.yaml   | 14 ++++++++++
 .../devicetree/bindings/iommu/tbu-common.yaml | 28 +++++++++++++++++++
 2 files changed, 42 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/iommu/tbu-common.yaml

diff --git a/Documentation/devicetree/bindings/iommu/arm,smmu.yaml b/Documentation/devicetree/bindings/iommu/arm,smmu.yaml
index a4042ae24770..ba3237023b39 100644
--- a/Documentation/devicetree/bindings/iommu/arm,smmu.yaml
+++ b/Documentation/devicetree/bindings/iommu/arm,smmu.yaml
@@ -235,6 +235,20 @@ properties:
       enabled for any given device.
     $ref: /schemas/types.yaml#/definitions/phandle
 
+  '#address-cells':
+    enum: [ 1, 2 ]
+
+  '#size-cells':
+    enum: [ 1, 2 ]
+
+  ranges: true
+
+patternProperties:
+  "^tbu@[0-9a-f]+$":
+    description: TBU child nodes
+    type: object
+    $ref: tbu-common.yaml#
+
 required:
   - compatible
   - reg
diff --git a/Documentation/devicetree/bindings/iommu/tbu-common.yaml b/Documentation/devicetree/bindings/iommu/tbu-common.yaml
new file mode 100644
index 000000000000..3e95b356e572
--- /dev/null
+++ b/Documentation/devicetree/bindings/iommu/tbu-common.yaml
@@ -0,0 +1,28 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/iommu/tbu-common.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Translation Buffer Unit (TBU) common properties
+
+maintainers:
+  - Georgi Djakov <quic_c_gdjako@xxxxxxxxxxx>
+
+description:
+  The SMMU implements a TBU for system masters. It consists if a
+  Translation Lookaside Buffer (TLB) that caches page tables.
+
+properties:
+  reg:
+    maxItems: 1
+
+  stream-id-range:
+    $ref: /schemas/types.yaml#/definitions/uint32-array
+    description: Stream ID range (address and size) that is assigned by the TBU
+    items:
+      minItems: 2
+      maxItems: 2
+
+additionalProperties: true
+...