[PATCH v4 2/5] dt-bindings: iommu: Add Broadcom BCM2712 IOMMU

[Daniel Drake]

Add bindings for the Broadcom BCM2712 IOMMUs and their shared TLB cache.

Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski at oss.qualcomm.com>
Signed-off-by: Daniel Drake <dan at reactivated.net>
---
 .../bindings/iommu/brcm,bcm2712-iommu.yaml         | 54 ++++++++++++++++++++++
 .../bindings/iommu/brcm,bcm2712-iommuc.yaml        | 40 ++++++++++++++++
 2 files changed, 94 insertions(+)

diff --git a/Documentation/devicetree/bindings/iommu/brcm,bcm2712-iommu.yaml b/Documentation/devicetree/bindings/iommu/brcm,bcm2712-iommu.yaml
new file mode 100644
index 000000000000..5ca8ce469ec3
--- /dev/null
+++ b/Documentation/devicetree/bindings/iommu/brcm,bcm2712-iommu.yaml
@@ -0,0 +1,54 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/iommu/brcm,bcm2712-iommu.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Broadcom BCM2712 IOMMU
+
+maintainers:
+  - Daniel Drake <dan at reactivated.net>
+  - Florian Fainelli <florian.fainelli at broadcom.com>
+  - Jim Quinlan <james.quinlan at broadcom.com>
+
+description:
+  The BCM2712 SoC features multiple independent IOMMU instances providing
+  address translation for multimedia hardware blocks, such as the VC6 display
+  pipeline, camera receivers, and ISP. Each IOMMU has its own page tables,
+  control registers, and local TLB, and is additionally linked to a centralized
+  L2 TLB (IOMMUC).
+
+properties:
+  compatible:
+    const: brcm,bcm2712-iommu
+
+  reg:
+    maxItems: 1
+
+  '#iommu-cells':
+    const: 0
+
+  brcm,iommu-cache:
+    $ref: /schemas/types.yaml#/definitions/phandle
+    description:
+      Phandle to the shared IOMMU cache (IOMMUC). Each IOMMU instance caches
+      translated descriptors in this centralized L2 TLB cache block and must
+      trigger cache invalidation commands on it when updating or unmapping page
+      table entries.
+
+required:
+  - compatible
+  - reg
+  - '#iommu-cells'
+  - brcm,iommu-cache
+
+additionalProperties: false
+
+examples:
+  - |
+    iommu at 5200 {
+        compatible = "brcm,bcm2712-iommu";
+        reg = <0x5200 0x80>;
+        brcm,iommu-cache = <&iommuc>;
+        #iommu-cells = <0>;
+    };
diff --git a/Documentation/devicetree/bindings/iommu/brcm,bcm2712-iommuc.yaml b/Documentation/devicetree/bindings/iommu/brcm,bcm2712-iommuc.yaml
new file mode 100644
index 000000000000..47c584ad667a
--- /dev/null
+++ b/Documentation/devicetree/bindings/iommu/brcm,bcm2712-iommuc.yaml
@@ -0,0 +1,40 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/iommu/brcm,bcm2712-iommuc.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Broadcom BCM2712 Shared IOMMU Cache (IOMMUC)
+
+maintainers:
+  - Daniel Drake <dan at reactivated.net>
+  - Florian Fainelli <florian.fainelli at broadcom.com>
+  - Jim Quinlan <james.quinlan at broadcom.com>
+
+description:
+  The BCM2712 IOMMUC is a centralized Translation Lookaside Buffer (TLB) cache
+  which accelerates address translation across the SoC's IOMMU devices. If an
+  address mapping is not found in the IOMMU's local TLB cache, then this
+  IOMMUC is consulted as a L2 TLB. The SoC includes a single IOMMUC which is
+  shared between all IOMMUs, and it must be explicitly invalidated when
+  modifying or unmapping IOMMU page tables.
+
+properties:
+  compatible:
+    const: brcm,bcm2712-iommuc
+
+  reg:
+    maxItems: 1
+
+required:
+  - compatible
+  - reg
+
+additionalProperties: false
+
+examples:
+  - |
+    iommuc at 5b00 {
+        compatible = "brcm,bcm2712-iommuc";
+        reg = <0x5b00 0x80>;
+    };

-- 
2.55.0