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
22allOf:
23  - $ref: serial.yaml#
24
25properties:
26  compatible:
27    oneOf:
28      - description: Always-on power domain UART controller
29        items:
30          - enum:
31              - amlogic,meson6-uart
32              - amlogic,meson8-uart
33              - amlogic,meson8b-uart
34              - amlogic,meson-gx-uart
35              - amlogic,meson-s4-uart
36          - const: amlogic,meson-ao-uart
37      - description: Everything-Else power domain UART controller
38        enum:
39          - amlogic,meson6-uart
40          - amlogic,meson8-uart
41          - amlogic,meson8b-uart
42          - amlogic,meson-gx-uart
43          - amlogic,meson-s4-uart
44
45  reg:
46    maxItems: 1
47
48  interrupts:
49    maxItems: 1
50
51  clocks:
52    items:
53      - description: external xtal clock identifier
54      - description: the bus core clock, either the clk81 clock or the gate clock
55      - description: the source of the baudrate generator, can be either the xtal or the pclk
56
57  clock-names:
58    items:
59      - const: xtal
60      - const: pclk
61      - const: baud
62
63  fifo-size:
64    description: The fifo size supported by the UART channel.
65    $ref: /schemas/types.yaml#/definitions/uint32
66    enum: [64, 128]
67
68required:
69  - compatible
70  - reg
71  - interrupts
72  - clocks
73  - clock-names
74
75unevaluatedProperties: false
76
77examples:
78  - |
79    serial@84c0 {
80        compatible = "amlogic,meson-gx-uart";
81        reg = <0x84c0 0x14>;
82        interrupts = <26>;
83        clocks = <&xtal>, <&pclk>, <&xtal>;
84        clock-names = "xtal", "pclk", "baud";
85    };
86