[PATCH v2 1/6] dt-bindings: iommu: Add Translation Buffer Unit bindings

Georgi Djakov quic_c_gdjako at quicinc.com
Fri Nov 17 20:27:25 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 also 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   | 25 ++++++
 .../bindings/iommu/qcom,qsmmuv500-tbu.yaml    | 89 +++++++++++++++++++
 2 files changed, 114 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 aa9e1c0895a5..f7f89be5f7a3 100644
--- a/Documentation/devicetree/bindings/iommu/arm,smmu.yaml
+++ b/Documentation/devicetree/bindings/iommu/arm,smmu.yaml
@@ -231,6 +231,18 @@ 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]*":
+    type: object
+
 required:
   - compatible
   - reg
@@ -453,6 +465,19 @@ allOf:
             - description: Voter clock required for HLOS SMMU access
             - description: Interface clock required for register access
 
+  - if:
+      properties:
+        compatible:
+          contains:
+            const: qcom,smmu-500
+    then:
+      patternProperties:
+        "^tbu@[0-9a-f]*":
+          $ref: qcom,qsmmuv500-tbu.yaml
+          unevaluatedProperties: false
+      properties:
+        ranges: true
+
   # Disallow clocks for all other platforms with specific compatibles
   - if:
       properties:
diff --git a/Documentation/devicetree/bindings/iommu/qcom,qsmmuv500-tbu.yaml b/Documentation/devicetree/bindings/iommu/qcom,qsmmuv500-tbu.yaml
new file mode 100644
index 000000000000..4dc9d0ca33c9
--- /dev/null
+++ b/Documentation/devicetree/bindings/iommu/qcom,qsmmuv500-tbu.yaml
@@ -0,0 +1,89 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$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:
+  $nodename:
+    pattern: "^tbu@[0-9a-f]+$"
+
+  compatible:
+    const: 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
+    items:
+      minItems: 2
+      maxItems: 2
+
+required:
+  - compatible
+  - reg
+  - interconnects
+  - qcom,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>;
+            reg-names = "base";
+            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>;
+            qcom,stream-id-range = <0x1c00 0x400>;
+        };
+    };
+
+...



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