162306a36Sopenharmony_ci# SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause)
262306a36Sopenharmony_ci# Copyright 2019 BayLibre, SAS
362306a36Sopenharmony_ci%YAML 1.2
462306a36Sopenharmony_ci---
562306a36Sopenharmony_ci$id: http://devicetree.org/schemas/mailbox/amlogic,meson-gxbb-mhu.yaml#
662306a36Sopenharmony_ci$schema: http://devicetree.org/meta-schemas/core.yaml#
762306a36Sopenharmony_ci
862306a36Sopenharmony_cititle: Amlogic Meson Message-Handling-Unit Controller
962306a36Sopenharmony_ci
1062306a36Sopenharmony_cimaintainers:
1162306a36Sopenharmony_ci  - Neil Armstrong <neil.armstrong@linaro.org>
1262306a36Sopenharmony_ci
1362306a36Sopenharmony_cidescription: |
1462306a36Sopenharmony_ci  The Amlogic's Meson SoCs Message-Handling-Unit (MHU) is a mailbox controller
1562306a36Sopenharmony_ci  that has 3 independent channels/links to communicate with remote processor(s).
1662306a36Sopenharmony_ci  MHU links are hardwired on a platform. A link raises interrupt for any
1762306a36Sopenharmony_ci  received data. However, there is no specified way of knowing if the sent
1862306a36Sopenharmony_ci  data has been read by the remote. This driver assumes the sender polls
1962306a36Sopenharmony_ci  STAT register and the remote clears it after having read the data.
2062306a36Sopenharmony_ci
2162306a36Sopenharmony_ciproperties:
2262306a36Sopenharmony_ci  compatible:
2362306a36Sopenharmony_ci    enum:
2462306a36Sopenharmony_ci      - amlogic,meson-gxbb-mhu
2562306a36Sopenharmony_ci
2662306a36Sopenharmony_ci  reg:
2762306a36Sopenharmony_ci    maxItems: 1
2862306a36Sopenharmony_ci
2962306a36Sopenharmony_ci  interrupts:
3062306a36Sopenharmony_ci    minItems: 3
3162306a36Sopenharmony_ci    description:
3262306a36Sopenharmony_ci      Contains the interrupt information corresponding to each of the 3 links
3362306a36Sopenharmony_ci      of MHU.
3462306a36Sopenharmony_ci
3562306a36Sopenharmony_ci  "#mbox-cells":
3662306a36Sopenharmony_ci    const: 1
3762306a36Sopenharmony_ci
3862306a36Sopenharmony_cirequired:
3962306a36Sopenharmony_ci  - compatible
4062306a36Sopenharmony_ci  - reg
4162306a36Sopenharmony_ci  - interrupts
4262306a36Sopenharmony_ci  - "#mbox-cells"
4362306a36Sopenharmony_ci
4462306a36Sopenharmony_ciadditionalProperties: false
4562306a36Sopenharmony_ci
4662306a36Sopenharmony_ciexamples:
4762306a36Sopenharmony_ci  - |
4862306a36Sopenharmony_ci    mailbox@c883c404 {
4962306a36Sopenharmony_ci          compatible = "amlogic,meson-gxbb-mhu";
5062306a36Sopenharmony_ci          reg = <0xc883c404 0x4c>;
5162306a36Sopenharmony_ci          interrupts = <208>, <209>, <210>;
5262306a36Sopenharmony_ci          #mbox-cells = <1>;
5362306a36Sopenharmony_ci    };
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