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+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+# Copyright (C) 2020 SiFive, Inc.
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/pwm/pwm-sifive.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: SiFive PWM controller
+
+maintainers:
+ - Paul Walmsley <paul.walmsley@sifive.com>
+
+description:
+ Unlike most other PWM controllers, the SiFive PWM controller currently
+ only supports one period for all channels in the PWM. All PWMs need to
+ run at the same period. The period also has significant restrictions on
+ the values it can achieve, which the driver rounds to the nearest
+ achievable period. PWM RTL that corresponds to the IP block version
+ numbers can be found here -
+
+ https://github.com/sifive/sifive-blocks/tree/master/src/main/scala/devices/pwm
+
+allOf:
+ - $ref: pwm.yaml#
+
+properties:
+ compatible:
+ items:
+ - enum:
+ - sifive,fu540-c000-pwm
+ - sifive,fu740-c000-pwm
+ - const: sifive,pwm0
+ description:
+ Should be "sifive,<chip>-pwm" and "sifive,pwm<version>". Supported
+ compatible strings are "sifive,fu540-c000-pwm" and
+ "sifive,fu740-c000-pwm" for the SiFive PWM v0 as integrated onto the
+ SiFive FU540 and FU740 chip respectively, and "sifive,pwm0" for the
+ SiFive PWM v0 IP block with no chip integration tweaks.
+ Please refer to sifive-blocks-ip-versioning.txt for details.
+
+ reg:
+ maxItems: 1
+
+ clocks:
+ maxItems: 1
+
+ "#pwm-cells":
+ const: 3
+
+ interrupts:
+ maxItems: 4
+ description:
+ Each PWM instance in FU540-C000 has 4 comparators. One interrupt per comparator.
+
+required:
+ - compatible
+ - reg
+ - clocks
+ - interrupts
+
+additionalProperties: false
+
+examples:
+ - |
+ pwm: pwm@10020000 {
+ compatible = "sifive,fu540-c000-pwm", "sifive,pwm0";
+ reg = <0x10020000 0x1000>;
+ clocks = <&tlclk>;
+ interrupt-parent = <&plic>;
+ interrupts = <42>, <43>, <44>, <45>;
+ #pwm-cells = <3>;
+ };