xref: /linux/Documentation/devicetree/bindings/serial/amlogic,meson-uart.yaml (revision 378ec25aec5a8444879f8696d580c94950a1f1df) 
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              - amlogic,meson-a1-uart
37          - const: amlogic,meson-ao-uart
38      - description: Always-on power domain UART controller on G12A SoCs
39        items:
40          - const: amlogic,meson-g12a-uart
41          - const: amlogic,meson-gx-uart
42          - const: amlogic,meson-ao-uart
43      - description: Everything-Else power domain UART controller
44        enum:
45          - amlogic,meson6-uart
46          - amlogic,meson8-uart
47          - amlogic,meson8b-uart
48          - amlogic,meson-gx-uart
49          - amlogic,meson-s4-uart
50          - amlogic,meson-a1-uart
51      - description: Everything-Else power domain UART controller on G12A SoCs
52        items:
53          - const: amlogic,meson-g12a-uart
54          - const: amlogic,meson-gx-uart
55      - description: UART controller on S4 compatible SoCs
56        items:
57          - enum:
58              - amlogic,a4-uart
59              - amlogic,s6-uart
60              - amlogic,s7-uart
61              - amlogic,s7d-uart
62              - amlogic,t7-uart
63          - const: amlogic,meson-s4-uart
64
65  reg:
66    maxItems: 1
67
68  interrupts:
69    maxItems: 1
70
71  clocks:
72    items:
73      - description: external xtal clock identifier
74      - description: the bus core clock, either the clk81 clock or the gate clock
75      - description: the source of the baudrate generator, can be either the xtal or the pclk
76
77  clock-names:
78    items:
79      - const: xtal
80      - const: pclk
81      - const: baud
82
83  fifo-size:
84    description: The fifo size supported by the UART channel.
85    $ref: /schemas/types.yaml#/definitions/uint32
86    enum: [64, 128]
87
88required:
89  - compatible
90  - reg
91  - interrupts
92  - clocks
93  - clock-names
94
95unevaluatedProperties: false
96
97examples:
98  - |
99    serial@84c0 {
100        compatible = "amlogic,meson-gx-uart";
101        reg = <0x84c0 0x14>;
102        interrupts = <26>;
103        clocks = <&xtal>, <&pclk>, <&xtal>;
104        clock-names = "xtal", "pclk", "baud";
105    };
106