dt-bindings: timer: Add EcoNet EN751221 "HPT" CPU Timer

Add device tree bindings for the so-called high-precision timer (HPT)
in the EcoNet EN751221 SoC.

Signed-off-by: Caleb James DeLisle <[email protected]>
Reviewed-by: Krzysztof Kozlowski <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Daniel Lezcano <[email protected]>

Author: cjdelisle

Documentation/devicetree/bindings/timer/econet,en751221-timer.yaml

@@ -0,0 +1,80 @@
+# SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/timer/econet,en751221-timer.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: EcoNet EN751221 High Precision Timer (HPT)
+
+maintainers:
+  - Caleb James DeLisle <[email protected]>
+
+description:
+  The EcoNet High Precision Timer (HPT) is a timer peripheral found in various
+  EcoNet SoCs, including the EN751221 and EN751627 families. It provides per-VPE
+  count/compare registers and a per-CPU control register, with a single interrupt
+  line using a percpu-devid interrupt mechanism.
+
+properties:
+  compatible:
+    oneOf:
+      - const: econet,en751221-timer
+      - items:
+          - const: econet,en751627-timer
+          - const: econet,en751221-timer
+
+  reg:
+    minItems: 1
+    maxItems: 2
+
+  interrupts:
+    maxItems: 1
+    description: A percpu-devid timer interrupt shared across CPUs.
+
+  clocks:
+    maxItems: 1
+
+required:
+  - compatible
+  - reg
+  - interrupts
+  - clocks
+
+allOf:
+  - if:
+      properties:
+        compatible:
+          contains:
+            const: econet,en751627-timer
+    then:
+      properties:
+        reg:
+          items:
+            - description: VPE timers 0 and 1
+            - description: VPE timers 2 and 3
+    else:
+      properties:
+        reg:
+          items:
+            - description: VPE timers 0 and 1
+
+additionalProperties: false
+
+examples:
+  - |
+    timer@1fbf0400 {
+        compatible = "econet,en751627-timer", "econet,en751221-timer";
+        reg = <0x1fbf0400 0x100>, <0x1fbe0000 0x100>;
+        interrupt-parent = <&intc>;
+        interrupts = <30>;
+        clocks = <&hpt_clock>;
+    };
+  - |
+    timer@1fbf0400 {
+        compatible = "econet,en751221-timer";
+        reg = <0x1fbe0400 0x100>;
+        interrupt-parent = <&intc>;
+        interrupts = <30>;
+        clocks = <&hpt_clock>;
+    };
+...