1# SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause)
2# Copyright 2019 BayLibre, SAS
3%YAML 1.2
4---
5$id: "http://devicetree.org/schemas/serial/amlogic,meson-uart.yaml#"
6$schema: "http://devicetree.org/meta-schemas/core.yaml#"
7
8title: Amlogic Meson SoC UART Serial Interface
9
10maintainers:
11  - Neil Armstrong <neil.armstrong@linaro.org>
12
13description: |
14  The Amlogic Meson SoC UART Serial Interface is present on a large range
15  of SoCs, and can be present either in the "Always-On" power domain or the
16  "Everything-Else" power domain.
17
18  The particularity of the "Always-On" Serial Interface is that the hardware
19  is active since power-on and does not need any clock gating and is usable
20  as very early serial console.
21
22properties:
23  compatible:
24    oneOf:
25      - description: Always-on power domain UART controller
26        items:
27          - enum:
28              - amlogic,meson6-uart
29              - amlogic,meson8-uart
30              - amlogic,meson8b-uart
31              - amlogic,meson-gx-uart
32              - amlogic,meson-s4-uart
33          - const: amlogic,meson-ao-uart
34      - description: Everything-Else power domain UART controller
35        enum:
36          - amlogic,meson6-uart
37          - amlogic,meson8-uart
38          - amlogic,meson8b-uart
39          - amlogic,meson-gx-uart
40          - amlogic,meson-s4-uart
41
42  reg:
43    maxItems: 1
44
45  interrupts:
46    maxItems: 1
47
48  clocks:
49    items:
50      - description: external xtal clock identifier
51      - description: the bus core clock, either the clk81 clock or the gate clock
52      - description: the source of the baudrate generator, can be either the xtal or the pclk
53
54  clock-names:
55    items:
56      - const: xtal
57      - const: pclk
58      - const: baud
59
60  fifo-size:
61    description: The fifo size supported by the UART channel.
62    $ref: /schemas/types.yaml#/definitions/uint32
63    enum: [64, 128]
64
65required:
66  - compatible
67  - reg
68  - interrupts
69  - clocks
70  - clock-names
71
72additionalProperties: false
73
74examples:
75  - |
76    serial@84c0 {
77          compatible = "amlogic,meson-gx-uart";
78          reg = <0x84c0 0x14>;
79          interrupts = <26>;
80          clocks = <&xtal>, <&pclk>, <&xtal>;
81          clock-names = "xtal", "pclk", "baud";
82    };
83