[PATCH 1/6] dt-bindings: iommu: Add Translation Buffer Unit bindings

[Georgi Djakov]

The "apps_smmu" on the Qualcomm sdm845 platform is an implementation
of the ARM SMMU-500, that consists of a single TCU (Translation Control
Unit) and multiple TBUs (Translation Buffer Units). The TCU is already
being described in the ARM SMMU DT schema. Add also bindings for the
TBUs so that we can describe their properties.

In this DT schema, the TBUs are modelled as a child devices of the TCU
and each of them is described with it's own resources such as clocks,
power domains, interconnects etc.

Signed-off-by: Georgi Djakov <quic_c_gdjako@xxxxxxxxxxx>
---
 .../devicetree/bindings/iommu/arm,smmu.yaml   | 13 ++++
 .../bindings/iommu/qcom,qsmmuv500-tbu.yaml    | 67 +++++++++++++++++++
 2 files changed, 80 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/iommu/qcom,qsmmuv500-tbu.yaml

diff --git a/Documentation/devicetree/bindings/iommu/arm,smmu.yaml b/Documentation/devicetree/bindings/iommu/arm,smmu.yaml
index cf29ab10501c..afc323b4bbc5 100644
--- a/Documentation/devicetree/bindings/iommu/arm,smmu.yaml
+++ b/Documentation/devicetree/bindings/iommu/arm,smmu.yaml
@@ -230,6 +230,19 @@ properties:
       enabled for any given device.
     $ref: /schemas/types.yaml#/definitions/phandle
 
+  '#address-cells':
+    const: 2
+
+  '#size-cells':
+    const: 2
+
+  ranges: true
+
+patternProperties:
+  "^tbu@[0-9a-f]+$":
+    $ref: qcom,qsmmuv500-tbu.yaml
+    description: The SMMU may include Translation Buffer Units (TBU) as subnodes
+
 required:
   - compatible
   - reg
diff --git a/Documentation/devicetree/bindings/iommu/qcom,qsmmuv500-tbu.yaml b/Documentation/devicetree/bindings/iommu/qcom,qsmmuv500-tbu.yaml
new file mode 100644
index 000000000000..4baba7397e90
--- /dev/null
+++ b/Documentation/devicetree/bindings/iommu/qcom,qsmmuv500-tbu.yaml
@@ -0,0 +1,67 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/iommu/qcom,qsmmuv500-tbu.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Qualcomm TBU (Translation Buffer Unit)
+
+maintainers:
+  - Georgi Djakov <quic_c_gdjako@xxxxxxxxxxx>
+
+description:
+  TBU nodes represent Translation Buffer Units in an ARM SMMU. Each TBU node
+  should be a child node of the SMMU in the device tree.
+
+properties:
+  compatible:
+    enum:
+      - qcom,qsmmuv500-tbu
+
+  reg:
+    items:
+      - description: Address and size of the TBU's register space.
+
+  reg-names:
+    items:
+      - const: base
+
+  clocks:
+    maxItems: 1
+
+  interconnects:
+    maxItems: 1
+
+  power-domains:
+    maxItems: 1
+
+  qcom,stream-id-range:
+    $ref: /schemas/types.yaml#/definitions/uint32-array
+    description: Stream ID range (address and size) that is assigned by the TBU
+
+required:
+  - compatible
+  - reg
+  - interconnects
+  - qcom,stream-id-range
+
+additionalProperties: false
+
+examples:
+  - |
+    #include <dt-bindings/clock/qcom,gcc-sdm845.h>
+    #include <dt-bindings/interconnect/qcom,sdm845.h>
+    #include <dt-bindings/power/qcom-rpmpd.h>
+
+
+    tbu@150e1000 {
+        compatible = "qcom,qsmmuv500-tbu";
+        reg = <0x150e1000 0x1000>;
+        reg-names = "base";
+        clocks = <&gcc GCC_AGGRE_NOC_PCIE_TBU_CLK>;
+        power-domains = <&gcc HLOS1_VOTE_AGGRE_NOC_MMU_PCIE_TBU_GDSC>;
+        interconnects = <&system_noc MASTER_GNOC_SNOC 0 &config_noc SLAVE_IMEM_CFG 0>;
+        qcom,stream-id-range = <0x1c00 0x400>;
+    };
+
+...