[PATCH v3 1/9] dt-bindings: iommu: Add Translation Buffer Unit bindings

Georgi Djakov quic_c_gdjako at quicinc.com
Tue Dec 19 22:02:28 PST 2023


The "apps_smmu" on the Qualcomm sdm845 platform is an implementation
of the 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 generic SMMU DT schema. Add bindings for the
TBUs to describe their properties and resources that needs to be
managed in order to operate them.

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

Signed-off-by: Georgi Djakov <quic_c_gdjako at quicinc.com>
---
 .../devicetree/bindings/iommu/arm,smmu.yaml   | 31 ++++++++
 .../bindings/iommu/qcom,qsmmuv500-tbu.yaml    | 77 +++++++++++++++++++
 2 files changed, 108 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 a4042ae24770..a610af2c7e5e 100644
--- a/Documentation/devicetree/bindings/iommu/arm,smmu.yaml
+++ b/Documentation/devicetree/bindings/iommu/arm,smmu.yaml
@@ -235,6 +235,27 @@ 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: The TBU child node(s)
+    type: object
+
+    properties:
+      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
+
 required:
   - compatible
   - reg
@@ -312,6 +333,16 @@ allOf:
                     through the TCU's programming interface.
                 - description: bus clock required for the smmu ptw
 
+  - if:
+      properties:
+        compatible:
+          contains:
+            const: qcom,sdm845-smmu-500
+    then:
+      patternProperties:
+        "^tbu@[0-9a-f]+":
+          $ref: qcom,qsmmuv500-tbu.yaml
+
   - if:
       properties:
         compatible:
diff --git a/Documentation/devicetree/bindings/iommu/qcom,qsmmuv500-tbu.yaml b/Documentation/devicetree/bindings/iommu/qcom,qsmmuv500-tbu.yaml
new file mode 100644
index 000000000000..c4f148ae5f38
--- /dev/null
+++ b/Documentation/devicetree/bindings/iommu/qcom,qsmmuv500-tbu.yaml
@@ -0,0 +1,77 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$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 at quicinc.com>
+
+description:
+  The Qualcomm SMMU500 implementation consists of TCU and TBU. The TBU contains
+  a Translation Lookaside Buffer (TLB) that caches page tables. TBUs provides
+  debug features to trace and trigger debug transactions. There are multiple TBU
+  instances distributes with each client core.
+
+properties:
+
+  compatible:
+    const: qcom,qsmmuv500-tbu
+
+  reg:
+    items:
+      - description: Address and size of the TBU's register space.
+
+  clocks:
+    maxItems: 1
+
+  interconnects:
+    maxItems: 1
+
+  power-domains:
+    maxItems: 1
+
+  stream-id-range:
+    $ref: "arm,smmu.yaml#/patternProperties/^tbu@[0-9a-f]+/properties/stream-id-range"
+
+required:
+  - compatible
+  - reg
+  - stream-id-range
+
+additionalProperties: false
+
+examples:
+  - |
+    #include <dt-bindings/clock/qcom,gcc-sdm845.h>
+    #include <dt-bindings/interconnect/qcom,icc.h>
+    #include <dt-bindings/interconnect/qcom,sdm845.h>
+    #include <dt-bindings/interrupt-controller/arm-gic.h>
+    #include <dt-bindings/interrupt-controller/irq.h>
+    #include <dt-bindings/power/qcom-rpmpd.h>
+
+    apps_smmu: iommu at 15000000 {
+        compatible = "qcom,sdm845-smmu-500", "arm,mmu-500";
+        reg = <0x15000000 0x80000>;
+        ranges = <0 0 0 0 0xffffffff>;
+        #iommu-cells = <2>;
+        #global-interrupts = <1>;
+        interrupts = <GIC_SPI 65 IRQ_TYPE_LEVEL_HIGH>,
+                     <GIC_SPI 343 IRQ_TYPE_LEVEL_HIGH>;
+        #address-cells = <2>;
+        #size-cells = <2>;
+
+        anoc_1_pcie_tbu: tbu at 150e1000 {
+            compatible = "qcom,qsmmuv500-tbu";
+            reg = <0x0 0x150e1000 0x0 0x1000>;
+            clocks = <&gcc GCC_AGGRE_NOC_PCIE_TBU_CLK>;
+            interconnects = <&system_noc MASTER_GNOC_SNOC QCOM_ICC_TAG_ACTIVE_ONLY
+                             &config_noc SLAVE_IMEM_CFG QCOM_ICC_TAG_ACTIVE_ONLY>;
+            power-domains = <&gcc HLOS1_VOTE_AGGRE_NOC_MMU_PCIE_TBU_GDSC>;
+            stream-id-range = <0x1c00 0x400>;
+        };
+    };
+
+...



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