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 - const: amlogic,t7-uart 58 - const: amlogic,meson-s4-uart 59 60 reg: 61 maxItems: 1 62 63 interrupts: 64 maxItems: 1 65 66 clocks: 67 items: 68 - description: external xtal clock identifier 69 - description: the bus core clock, either the clk81 clock or the gate clock 70 - description: the source of the baudrate generator, can be either the xtal or the pclk 71 72 clock-names: 73 items: 74 - const: xtal 75 - const: pclk 76 - const: baud 77 78 fifo-size: 79 description: The fifo size supported by the UART channel. 80 $ref: /schemas/types.yaml#/definitions/uint32 81 enum: [64, 128] 82 83required: 84 - compatible 85 - reg 86 - interrupts 87 - clocks 88 - clock-names 89 90unevaluatedProperties: false 91 92examples: 93 - | 94 serial@84c0 { 95 compatible = "amlogic,meson-gx-uart"; 96 reg = <0x84c0 0x14>; 97 interrupts = <26>; 98 clocks = <&xtal>, <&pclk>, <&xtal>; 99 clock-names = "xtal", "pclk", "baud"; 100 }; 101