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