dt-bindings: Add devicetree bindings

Add snapshot of device tree bindings from keystone common kernel, branch
"android-mainline-keystone-qcom-release" at c4c12103f9c0 ("Snap for 9228065
from e32903b9a63bb558df8b803b076619c53c16baad to
android-mainline-keystone-qcom-release").

Change-Id: I7682079615cbd9f29340a5c1f2a1d84ec441a1f1
Signed-off-by: Melody Olvera <quic_molvera@quicinc.com>

bindings/bus/brcm,gisb-arb.yaml

@@ -0,0 +1,66 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/bus/brcm,gisb-arb.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Broadcom GISB bus Arbiter controller
+
+maintainers:
+  - Florian Fainelli <f.fainelli@gmail.com>
+
+properties:
+  compatible:
+    oneOf:
+      - items:
+          - enum:
+              - brcm,bcm7445-gisb-arb  # for other 28nm chips
+          - const: brcm,gisb-arb
+      - items:
+          - enum:
+              - brcm,bcm7278-gisb-arb  # for V7 28nm chips
+              - brcm,bcm7435-gisb-arb  # for newer 40nm chips
+              - brcm,bcm7400-gisb-arb  # for older 40nm chips and all 65nm chips
+              - brcm,bcm7038-gisb-arb  # for 130nm chips
+              - brcm,gisb-arb          # fallback compatible
+
+  reg:
+    maxItems: 1
+
+  interrupts:
+    minItems: 2
+    items:
+      - description: timeout interrupt line
+      - description: target abort interrupt line
+      - description: breakpoint interrupt line
+
+  brcm,gisb-arb-master-mask:
+    $ref: /schemas/types.yaml#/definitions/uint32
+    description: >
+      32-bits wide bitmask used to specify which GISB masters are valid at the
+      system level
+
+  brcm,gisb-arb-master-names:
+    $ref: /schemas/types.yaml#/definitions/string-array
+    description: >
+      String list of the litteral name of the GISB masters. Should match the
+      number of bits set in brcm,gisb-master-mask and the order in which they
+      appear from MSB to LSB.
+
+required:
+  - compatible
+  - reg
+  - interrupts
+
+additionalProperties: false
+
+examples:
+  - |
+    gisb-arb@f0400000 {
+      compatible = "brcm,gisb-arb";
+      reg = <0xf0400000 0x800>;
+      interrupts = <0>, <2>;
+      interrupt-parent = <&sun_l2_intc>;
+      brcm,gisb-arb-master-mask = <0x7>;
+      brcm,gisb-arb-master-names = "bsp_0", "scpu_0", "cpu_0";
+    };