[PATCH v4 02/10] dt-bindings: iommu: Add Qualcomm TBU bindings

Georgi Djakov quic_c_gdjako at quicinc.com
Thu Feb 1 13:05:21 PST 2024


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 ARM SMMU schema and now we have also a common
schema for TBUs. The TBUs on Qualcomm platforms have some additional
hardware resources that need to be described in the schema. Create a
vendor-specific TBU schema to include all the needed resources like
clocks, power domains and interconnects.

Signed-off-by: Georgi Djakov <quic_c_gdjako at quicinc.com>
---
 .../devicetree/bindings/iommu/arm,smmu.yaml   | 10 +++
 .../bindings/iommu/qcom,qsmmuv500-tbu.yaml    | 71 +++++++++++++++++++
 2 files changed, 81 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 ba3237023b39..537e6a2fc02b 100644
--- a/Documentation/devicetree/bindings/iommu/arm,smmu.yaml
+++ b/Documentation/devicetree/bindings/iommu/arm,smmu.yaml
@@ -326,6 +326,16 @@ 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]+$":
+          $ref: qcom,qsmmuv500-tbu.yaml#
+
   - if:
       properties:
         compatible:
diff --git a/Documentation/devicetree/bindings/iommu/qcom,qsmmuv500-tbu.yaml b/Documentation/devicetree/bindings/iommu/qcom,qsmmuv500-tbu.yaml
new file mode 100644
index 000000000000..0e86e1c42133
--- /dev/null
+++ b/Documentation/devicetree/bindings/iommu/qcom,qsmmuv500-tbu.yaml
@@ -0,0 +1,71 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$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 with each client core.
+
+allOf:
+  - $ref: tbu-common.yaml#
+
+properties:
+  compatible:
+    const: qcom,qsmmuv500-tbu
+
+  clocks:
+    maxItems: 1
+
+  interconnects:
+    maxItems: 1
+
+  power-domains:
+    maxItems: 1
+
+required:
+  - compatible
+  - reg
+  - stream-id-range
+
+unevaluatedProperties: 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>
+
+    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>;
+
+        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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