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
56  reg:
57    maxItems: 1
58
59  interrupts:
60    maxItems: 1
61
62  clocks:
63    items:
64      - description: external xtal clock identifier
65      - description: the bus core clock, either the clk81 clock or the gate clock
66      - description: the source of the baudrate generator, can be either the xtal or the pclk
67
68  clock-names:
69    items:
70      - const: xtal
71      - const: pclk
72      - const: baud
73
74  fifo-size:
75    description: The fifo size supported by the UART channel.
76    $ref: /schemas/types.yaml#/definitions/uint32
77    enum: [64, 128]
78
79required:
80  - compatible
81  - reg
82  - interrupts
83  - clocks
84  - clock-names
85
86unevaluatedProperties: false
87
88examples:
89  - |
90    serial@84c0 {
91        compatible = "amlogic,meson-gx-uart";
92        reg = <0x84c0 0x14>;
93        interrupts = <26>;
94        clocks = <&xtal>, <&pclk>, <&xtal>;
95        clock-names = "xtal", "pclk", "baud";
96    };
97