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# SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause)
# Copyright 2019 BayLibre, SAS
%YAML 1.2
---
$id: "http://devicetree.org/schemas/serial/amlogic,meson-uart.yaml#"
$schema: "http://devicetree.org/meta-schemas/core.yaml#"
title: Amlogic Meson SoC UART Serial Interface
maintainers:
- Neil Armstrong <narmstrong@baylibre.com>
description: |
The Amlogic Meson SoC UART Serial Interface is present on a large range
of SoCs, and can be present either in the "Always-On" power domain or the
"Everything-Else" power domain.
The particularity of the "Always-On" Serial Interface is that the hardware
is active since power-on and does not need any clock gating and is usable
as very early serial console.
properties:
compatible:
oneOf:
- description: Always-on power domain UART controller
items:
- enum:
- amlogic,meson6-uart
- amlogic,meson8-uart
- amlogic,meson8b-uart
- amlogic,meson-gx-uart
- amlogic,meson-s4-uart
- const: amlogic,meson-ao-uart
- description: Everything-Else power domain UART controller
enum:
- amlogic,meson6-uart
- amlogic,meson8-uart
- amlogic,meson8b-uart
- amlogic,meson-gx-uart
- amlogic,meson-s4-uart
reg:
maxItems: 1
interrupts:
maxItems: 1
clocks:
items:
- description: external xtal clock identifier
- description: the bus core clock, either the clk81 clock or the gate clock
- description: the source of the baudrate generator, can be either the xtal or the pclk
clock-names:
items:
- const: xtal
- const: pclk
- const: baud
fifo-size:
description: The fifo size supported by the UART channel.
$ref: /schemas/types.yaml#/definitions/uint32
enum: [64, 128]
required:
- compatible
- reg
- interrupts
- clocks
- clock-names
additionalProperties: false
examples:
- |
serial@84c0 {
compatible = "amlogic,meson-gx-uart";
reg = <0x84c0 0x14>;
interrupts = <26>;
clocks = <&xtal>, <&pclk>, <&xtal>;
clock-names = "xtal", "pclk", "baud";
};
|
