Several SoMs and boards are available that feature the Allwinner D1 SoC.
Document their compatible strings.

Signed-off-by: Samuel Holland <samuel@sholland.org>
---

 .../devicetree/bindings/riscv/sunxi.yaml      | 64 +++++++++++++++++++
 1 file changed, 64 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/riscv/sunxi.yaml

diff --git a/Documentation/devicetree/bindings/riscv/sunxi.yaml b/Documentation/devicetree/bindings/riscv/sunxi.yaml
new file mode 100644
index 000000000000..564a89499894
--- /dev/null
+++ b/Documentation/devicetree/bindings/riscv/sunxi.yaml

@@ -0,0 +1,64 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/riscv/sunxi.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Allwinner RISC-V SoC-based boards
+
+maintainers:
+  - Chen-Yu Tsai <wens@csie.org>
+  - Jernej Skrabec <jernej.skrabec@gmail.com>
+  - Samuel Holland <samuel@sholland.org>
+
+description:
+  Allwinner RISC-V SoC-based boards
+
+properties:
+  $nodename:
+    const: '/'
+  compatible:
+    oneOf:
+      - description: Dongshan Nezha STU SoM
+        items:
+          - const: 100ask,dongshan-nezha-stu
+          - const: allwinner,sun20i-d1
+
+      - description: D1 Nezha board
+        items:
+          - const: allwinner,d1-nezha