1 # SPDX-License-Identifier: (GPL-2.0 OR BSD-2-C 1 # SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause)
2 # Copyright 2019 BayLibre, SAS 2 # Copyright 2019 BayLibre, SAS
3 %YAML 1.2 3 %YAML 1.2
4 --- 4 ---
5 $id: http://devicetree.org/schemas/mailbox/aml 5 $id: http://devicetree.org/schemas/mailbox/amlogic,meson-gxbb-mhu.yaml#
6 $schema: http://devicetree.org/meta-schemas/co 6 $schema: http://devicetree.org/meta-schemas/core.yaml#
7 7
8 title: Amlogic Meson Message-Handling-Unit Con 8 title: Amlogic Meson Message-Handling-Unit Controller
9 9
10 maintainers: 10 maintainers:
11 - Neil Armstrong <neil.armstrong@linaro.org> 11 - Neil Armstrong <neil.armstrong@linaro.org>
12 12
13 description: | 13 description: |
14 The Amlogic's Meson SoCs Message-Handling-Un 14 The Amlogic's Meson SoCs Message-Handling-Unit (MHU) is a mailbox controller
15 that has 3 independent channels/links to com 15 that has 3 independent channels/links to communicate with remote processor(s).
16 MHU links are hardwired on a platform. A lin 16 MHU links are hardwired on a platform. A link raises interrupt for any
17 received data. However, there is no specifie 17 received data. However, there is no specified way of knowing if the sent
18 data has been read by the remote. This drive 18 data has been read by the remote. This driver assumes the sender polls
19 STAT register and the remote clears it after 19 STAT register and the remote clears it after having read the data.
20 20
21 properties: 21 properties:
22 compatible: 22 compatible:
23 enum: 23 enum:
24 - amlogic,meson-gxbb-mhu 24 - amlogic,meson-gxbb-mhu
25 25
26 reg: 26 reg:
27 maxItems: 1 27 maxItems: 1
28 28
29 interrupts: 29 interrupts:
30 minItems: 3 30 minItems: 3
31 description: 31 description:
32 Contains the interrupt information corre 32 Contains the interrupt information corresponding to each of the 3 links
33 of MHU. 33 of MHU.
34 34
35 "#mbox-cells": 35 "#mbox-cells":
36 const: 1 36 const: 1
37 37
38 required: 38 required:
39 - compatible 39 - compatible
40 - reg 40 - reg
41 - interrupts 41 - interrupts
42 - "#mbox-cells" 42 - "#mbox-cells"
43 43
44 additionalProperties: false 44 additionalProperties: false
45 45
46 examples: 46 examples:
47 - | 47 - |
48 mailbox@c883c404 { 48 mailbox@c883c404 {
49 compatible = "amlogic,meson-gxbb-mhu 49 compatible = "amlogic,meson-gxbb-mhu";
50 reg = <0xc883c404 0x4c>; 50 reg = <0xc883c404 0x4c>;
51 interrupts = <208>, <209>, <210>; 51 interrupts = <208>, <209>, <210>;
52 #mbox-cells = <1>; 52 #mbox-cells = <1>;
53 }; 53 };
Linux® is a registered trademark of Linus Torvalds in the United States and other countries.
TOMOYO® is a registered trademark of NTT DATA CORPORATION.