dt-bindings: arm: Add NVIDIA Tegra194 CPU Complex binding

Add device-tree binding documentation to represent Tegra194
CPU Complex with compatible string under 'cpus' node. This
can be used by drivers like cpufreq which don't have their
node or CPU Complex node to bind to. Also, documenting
'nvidia,bpmp' property which points to BPMP device.
Signed-off-by: Sumit Gupta <sumitg@nvidia.com>
Reviewed-by: Rob Herring <robh@kernel.org>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>

Documentation/devicetree/bindings/arm/nvidia,tegra194-ccplex.yaml

+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: "http://devicetree.org/schemas/arm/nvidia,tegra194-ccplex.yaml#"
+$schema: "http://devicetree.org/meta-schemas/core.yaml#"
+
+title: NVIDIA Tegra194 CPU Complex device tree bindings
+
+maintainers:
+  - Thierry Reding <thierry.reding@gmail.com>
+  - Jonathan Hunter <jonathanh@nvidia.com>
+  - Sumit Gupta <sumitg@nvidia.com>
+
+description: |+
+  Tegra194 SOC has homogeneous architecture where each cluster has two
+  symmetric cores. Compatible string in "cpus" node represents the CPU
+  Complex having all clusters.
+
+properties:
+  $nodename:
+    const: cpus
+
+  compatible:
+    enum:
+      - nvidia,tegra194-ccplex
+
+  nvidia,bpmp:
+    $ref: '/schemas/types.yaml#/definitions/phandle'
+    description: |
+      Specifies the bpmp node that needs to be queried to get
+      operating point data for all CPUs.
+
+examples:
+  - |
+    cpus {
+      compatible = "nvidia,tegra194-ccplex";
+      nvidia,bpmp = <&bpmp>;
+      #address-cells = <1>;
+      #size-cells = <0>;
+
+      cpu0_0: cpu@0 {
+        compatible = "nvidia,tegra194-carmel";
+        device_type = "cpu";
+        reg = <0x0>;
+        enable-method = "psci";
+      };
+
+      cpu0_1: cpu@1 {
+        compatible = "nvidia,tegra194-carmel";
+        device_type = "cpu";
+        reg = <0x001>;
+        enable-method = "psci";
+      };
+
+      cpu1_0: cpu@100 {
+        compatible = "nvidia,tegra194-carmel";
+        device_type = "cpu";
+        reg = <0x100>;
+        enable-method = "psci";
+      };
+
+      cpu1_1: cpu@101 {
+        compatible = "nvidia,tegra194-carmel";
+        device_type = "cpu";
+        reg = <0x101>;
+        enable-method = "psci";
+      };
+    };
+...