xref: /freebsd/sys/contrib/device-tree/Bindings/mailbox/amlogic,meson-gxbb-mhu.yaml (revision fac71e4e09885bb2afa3d984a0c239a52e1a7418)
1c66ec88fSEmmanuel Vadot# SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause)
2c66ec88fSEmmanuel Vadot# Copyright 2019 BayLibre, SAS
3c66ec88fSEmmanuel Vadot%YAML 1.2
4c66ec88fSEmmanuel Vadot---
5*fac71e4eSEmmanuel Vadot$id: http://devicetree.org/schemas/mailbox/amlogic,meson-gxbb-mhu.yaml#
6*fac71e4eSEmmanuel Vadot$schema: http://devicetree.org/meta-schemas/core.yaml#
7c66ec88fSEmmanuel Vadot
8c66ec88fSEmmanuel Vadottitle: Amlogic Meson Message-Handling-Unit Controller
9c66ec88fSEmmanuel Vadot
10c66ec88fSEmmanuel Vadotmaintainers:
11b97ee269SEmmanuel Vadot  - Neil Armstrong <neil.armstrong@linaro.org>
12c66ec88fSEmmanuel Vadot
13c66ec88fSEmmanuel Vadotdescription: |
14c66ec88fSEmmanuel Vadot  The Amlogic's Meson SoCs Message-Handling-Unit (MHU) is a mailbox controller
15c66ec88fSEmmanuel Vadot  that has 3 independent channels/links to communicate with remote processor(s).
16c66ec88fSEmmanuel Vadot  MHU links are hardwired on a platform. A link raises interrupt for any
17c66ec88fSEmmanuel Vadot  received data. However, there is no specified way of knowing if the sent
18c66ec88fSEmmanuel Vadot  data has been read by the remote. This driver assumes the sender polls
19c66ec88fSEmmanuel Vadot  STAT register and the remote clears it after having read the data.
20c66ec88fSEmmanuel Vadot
21c66ec88fSEmmanuel Vadotproperties:
22c66ec88fSEmmanuel Vadot  compatible:
23c66ec88fSEmmanuel Vadot    enum:
24c66ec88fSEmmanuel Vadot      - amlogic,meson-gxbb-mhu
25c66ec88fSEmmanuel Vadot
26c66ec88fSEmmanuel Vadot  reg:
27c66ec88fSEmmanuel Vadot    maxItems: 1
28c66ec88fSEmmanuel Vadot
29c66ec88fSEmmanuel Vadot  interrupts:
30c66ec88fSEmmanuel Vadot    minItems: 3
31c66ec88fSEmmanuel Vadot    description:
32c66ec88fSEmmanuel Vadot      Contains the interrupt information corresponding to each of the 3 links
33c66ec88fSEmmanuel Vadot      of MHU.
34c66ec88fSEmmanuel Vadot
35c66ec88fSEmmanuel Vadot  "#mbox-cells":
36c66ec88fSEmmanuel Vadot    const: 1
37c66ec88fSEmmanuel Vadot
38c66ec88fSEmmanuel Vadotrequired:
39c66ec88fSEmmanuel Vadot  - compatible
40c66ec88fSEmmanuel Vadot  - reg
41c66ec88fSEmmanuel Vadot  - interrupts
42c66ec88fSEmmanuel Vadot  - "#mbox-cells"
43c66ec88fSEmmanuel Vadot
44c66ec88fSEmmanuel VadotadditionalProperties: false
45c66ec88fSEmmanuel Vadot
46c66ec88fSEmmanuel Vadotexamples:
47c66ec88fSEmmanuel Vadot  - |
48c66ec88fSEmmanuel Vadot    mailbox@c883c404 {
49c66ec88fSEmmanuel Vadot          compatible = "amlogic,meson-gxbb-mhu";
50c66ec88fSEmmanuel Vadot          reg = <0xc883c404 0x4c>;
51c66ec88fSEmmanuel Vadot          interrupts = <208>, <209>, <210>;
52c66ec88fSEmmanuel Vadot          #mbox-cells = <1>;
53c66ec88fSEmmanuel Vadot    };
54