dt-bindings: bus: add CDX bus controller for versal net

Add CDX bus controller device tree bindings for versal-net
devices.

Signed-off-by: Nipun Gupta <nipun.gupta@amd.com>
Reviewed-by: Rob Herring <robh@kernel.org>
Reviewed-by: Pieter Jansen van Vuuren <pieter.jansen-van-vuuren@amd.com>
Tested-by: Nikhil Agarwal <nikhil.agarwal@amd.com>
Link: https://lore.kernel.org/r/20230313132636.31850-4-nipun.gupta@amd.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Documentation/devicetree/bindings/bus/xlnx,versal-net-cdx.yaml

@@ -0,0 +1,82 @@
+# SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/bus/xlnx,versal-net-cdx.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: AMD CDX bus controller
+
+description: |
+  CDX bus controller for AMD devices is implemented to dynamically
+  detect CDX bus and devices using the firmware.
+  The CDX bus manages multiple FPGA based hardware devices, which
+  can support network, crypto or any other specialized type of
+  devices. These FPGA based devices can be added/modified dynamically
+  on run-time.
+
+  All devices on the CDX bus will have a unique streamid (for IOMMU)
+  and a unique device ID (for MSI) corresponding to a requestor ID
+  (one to one associated with the device). The streamid and deviceid
+  are used to configure SMMU and GIC-ITS respectively.
+
+  iommu-map property is used to define the set of stream ids
+  corresponding to each device and the associated IOMMU.
+
+  The MSI writes are accompanied by sideband data (Device ID).
+  The msi-map property is used to associate the devices with the
+  device ID as well as the associated ITS controller.
+
+  rproc property (xlnx,rproc) is used to identify the remote processor
+  with which APU (Application Processor Unit) interacts to find out
+  the bus and device configuration.
+
+maintainers:
+  - Nipun Gupta <nipun.gupta@amd.com>
+  - Nikhil Agarwal <nikhil.agarwal@amd.com>
+
+properties:
+  compatible:
+    const: xlnx,versal-net-cdx
+
+  iommu-map: true
+
+  msi-map: true
+
+  xlnx,rproc:
+    $ref: /schemas/types.yaml#/definitions/phandle
+    description:
+      phandle to the remoteproc_r5 rproc node using which APU interacts
+      with remote processor.
+
+  ranges: true
+
+  "#address-cells":
+    enum: [1, 2]
+
+  "#size-cells":
+    enum: [1, 2]
+
+required:
+  - compatible
+  - iommu-map
+  - msi-map
+  - xlnx,rproc
+  - ranges
+  - "#address-cells"
+  - "#size-cells"
+
+additionalProperties: false
+
+examples:
+  - |
+    cdx {
+        compatible = "xlnx,versal-net-cdx";
+        #address-cells = <1>;
+        #size-cells = <1>;
+        /* define map for RIDs 250-259 */
+        iommu-map = <250 &smmu 250 10>;
+        /* define msi map for RIDs 250-259 */
+        msi-map = <250 &its 250 10>;
+        xlnx,rproc = <&remoteproc_r5>;
+        ranges;
+    };

MAINTAINERS

@@ -968,6 +968,7 @@ AMD CDX BUS DRIVER
 M:	Nipun Gupta <nipun.gupta@amd.com>
 M:	Nikhil Agarwal <nikhil.agarwal@amd.com>
 S:	Maintained
+F:	Documentation/devicetree/bindings/bus/xlnx,versal-net-cdx.yaml
 F:	drivers/cdx/*
 F:	include/linux/cdx/*