[PATCH v2 02/11] dt-bindings: Add binding for gunyah hypervisor

[Elliot Berman]

When Linux is booted as a guest under the Gunyah hypervisor, Gunyah
applies a devicetree overlay describing the virtual platform
configuration of the guest VM, such as the message queue capability IDs
for communicating with the Resource Manager. Add the DT bindings that
Gunyah adheres for the hypervisor node and message queues.

Signed-off-by: Elliot Berman <quic_eberman at quicinc.com>
---
 .../bindings/firmware/gunyah-hypervisor.yaml  | 84 +++++++++++++++++++
 MAINTAINERS                                   |  1 +
 2 files changed, 85 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/firmware/gunyah-hypervisor.yaml

diff --git a/Documentation/devicetree/bindings/firmware/gunyah-hypervisor.yaml b/Documentation/devicetree/bindings/firmware/gunyah-hypervisor.yaml
new file mode 100644
index 000000000000..e50d932e768c
--- /dev/null
+++ b/Documentation/devicetree/bindings/firmware/gunyah-hypervisor.yaml
@@ -0,0 +1,84 @@
+# SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/firmware/gunyah-hypervisor.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Gunyah Hypervisor
+
+maintainers:
+  - Murali Nalajala <quic_mnalajal at quicinc.com>
+  - Elliot Berman <quic_eberman at quicinc.com>
+
+description: |+
+  On systems which support devicetree, Gunyah generates and overlays a deviceetree overlay which
+  describes the basic configuration of the hypervisor. Virtual machines use this information for
+  initial discovery that they are running as a Gunyah guest VM.
+  See also: https://github.com/quic/gunyah-resource-manager/blob/develop/src/vm_creation/dto_construct.c
+
+properties:
+  compatible:
+    oneOf:
+      - items:
+          - const: gunyah-hypervisor-1.0
+          - const: gunyah-hypervisor
+
+  "#address-cells":
+    description: Number of cells needed to represent 64-bit capability IDs.
+    const: 2
+  "#size-cells":
+    description: must be 0, because capability IDs are not memory address
+                  ranges and do not have a size.
+    const: 0
+
+patternProperties:
+  "^gunyah-resource-mgr(@.*)?":
+    type: object
+    description:
+      Resource Manager node which is required to communicate to Resource
+      Manager VM using Gunyah Message Queues.
+
+    properties:
+      compatible:
+        oneOf:
+          - items:
+              - const: gunyah-resource-manager-1-0
+              - const: gunyah-resource-manager
+      reg:
+        items:
+          - description: Gunyah capability ID of the TX message queue
+          - description: Gunyah capability ID of the RX message queue
+      interrupts:
+        items:
+          - description: Interrupt for the TX message queue
+          - description: Interrupt for the RX message queue
+    additionalProperties: false
+    required:
+      - compatible
+      - reg
+      - interrupts
+
+additionalProperties: false
+
+required:
+  - compatible
+  - "#address-cells"
+  - "#size-cells"
+
+examples:
+  - |
+    #include <dt-bindings/interrupt-controller/arm-gic.h>
+
+    hypervisor {
+        #address-cells = <2>;
+        #size-cells = <0>;
+        compatible = "gunyah-hypervisor-1.0", "gunyah-hypervisor";
+
+        gunyah-resource-mgr at 1 {
+            compatible = "gunyah-resource-manager-1-0", "gunyah-resource-manager";
+            interrupts = <GIC_SPI 3 IRQ_TYPE_EDGE_RISING>, /* TX full IRQ */
+                         <GIC_SPI 4 IRQ_TYPE_EDGE_RISING>; /* RX empty IRQ */
+            reg = <0x00000000 0x00000000>, <0x00000000 0x00000001>;
+                  /* TX, RX cap ids */
+        };
+    };
diff --git a/MAINTAINERS b/MAINTAINERS
index 18fb034526e1..0cd12ea6c11c 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -8741,6 +8741,7 @@ M:	Elliot Berman <quic_eberman at quicinc.com>
 M:	Murali Nalajala <quic_mnalajal at quicinc.com>
 L:	linux-arm-msm at vger.kernel.org
 S:	Maintained
+F:	Documentation/devicetree/bindings/firmware/gunyah-hypervisor.yaml
 F:	Documentation/virt/gunyah/
 
 HABANALABS PCI DRIVER
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2.25.1