xref: /linux/Documentation/devicetree/bindings/serial/amlogic,meson-uart.yaml (revision 58f6259b7a08f8d47d4629609703d358b042f0fd) 
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: Always-on power domain UART controller on G12A SoCs
38        items:
39          - const: amlogic,meson-g12a-uart
40          - const: amlogic,meson-gx-uart
41          - const: amlogic,meson-ao-uart
42      - description: Everything-Else power domain UART controller
43        enum:
44          - amlogic,meson6-uart
45          - amlogic,meson8-uart
46          - amlogic,meson8b-uart
47          - amlogic,meson-gx-uart
48          - amlogic,meson-s4-uart
49      - description: Everything-Else power domain UART controller on G12A SoCs
50        items:
51          - const: amlogic,meson-g12a-uart
52          - const: amlogic,meson-gx-uart
53
54  reg:
55    maxItems: 1
56
57  interrupts:
58    maxItems: 1
59
60  clocks:
61    items:
62      - description: external xtal clock identifier
63      - description: the bus core clock, either the clk81 clock or the gate clock
64      - description: the source of the baudrate generator, can be either the xtal or the pclk
65
66  clock-names:
67    items:
68      - const: xtal
69      - const: pclk
70      - const: baud
71
72  fifo-size:
73    description: The fifo size supported by the UART channel.
74    $ref: /schemas/types.yaml#/definitions/uint32
75    enum: [64, 128]
76
77required:
78  - compatible
79  - reg
80  - interrupts
81  - clocks
82  - clock-names
83
84unevaluatedProperties: false
85
86examples:
87  - |
88    serial@84c0 {
89        compatible = "amlogic,meson-gx-uart";
90        reg = <0x84c0 0x14>;
91        interrupts = <26>;
92        clocks = <&xtal>, <&pclk>, <&xtal>;
93        clock-names = "xtal", "pclk", "baud";
94    };
95