1*4882a593Smuzhiyun# SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause) 2*4882a593Smuzhiyun# Copyright 2019 BayLibre, SAS 3*4882a593Smuzhiyun%YAML 1.2 4*4882a593Smuzhiyun--- 5*4882a593Smuzhiyun$id: "http://devicetree.org/schemas/mailbox/amlogic,meson-gxbb-mhu.yaml#" 6*4882a593Smuzhiyun$schema: "http://devicetree.org/meta-schemas/core.yaml#" 7*4882a593Smuzhiyun 8*4882a593Smuzhiyuntitle: Amlogic Meson Message-Handling-Unit Controller 9*4882a593Smuzhiyun 10*4882a593Smuzhiyunmaintainers: 11*4882a593Smuzhiyun - Neil Armstrong <narmstrong@baylibre.com> 12*4882a593Smuzhiyun 13*4882a593Smuzhiyundescription: | 14*4882a593Smuzhiyun The Amlogic's Meson SoCs Message-Handling-Unit (MHU) is a mailbox controller 15*4882a593Smuzhiyun that has 3 independent channels/links to communicate with remote processor(s). 16*4882a593Smuzhiyun MHU links are hardwired on a platform. A link raises interrupt for any 17*4882a593Smuzhiyun received data. However, there is no specified way of knowing if the sent 18*4882a593Smuzhiyun data has been read by the remote. This driver assumes the sender polls 19*4882a593Smuzhiyun STAT register and the remote clears it after having read the data. 20*4882a593Smuzhiyun 21*4882a593Smuzhiyunproperties: 22*4882a593Smuzhiyun compatible: 23*4882a593Smuzhiyun enum: 24*4882a593Smuzhiyun - amlogic,meson-gxbb-mhu 25*4882a593Smuzhiyun 26*4882a593Smuzhiyun reg: 27*4882a593Smuzhiyun maxItems: 1 28*4882a593Smuzhiyun 29*4882a593Smuzhiyun interrupts: 30*4882a593Smuzhiyun minItems: 3 31*4882a593Smuzhiyun description: 32*4882a593Smuzhiyun Contains the interrupt information corresponding to each of the 3 links 33*4882a593Smuzhiyun of MHU. 34*4882a593Smuzhiyun 35*4882a593Smuzhiyun "#mbox-cells": 36*4882a593Smuzhiyun const: 1 37*4882a593Smuzhiyun 38*4882a593Smuzhiyunrequired: 39*4882a593Smuzhiyun - compatible 40*4882a593Smuzhiyun - reg 41*4882a593Smuzhiyun - interrupts 42*4882a593Smuzhiyun - "#mbox-cells" 43*4882a593Smuzhiyun 44*4882a593SmuzhiyunadditionalProperties: false 45*4882a593Smuzhiyun 46*4882a593Smuzhiyunexamples: 47*4882a593Smuzhiyun - | 48*4882a593Smuzhiyun mailbox@c883c404 { 49*4882a593Smuzhiyun compatible = "amlogic,meson-gxbb-mhu"; 50*4882a593Smuzhiyun reg = <0xc883c404 0x4c>; 51*4882a593Smuzhiyun interrupts = <208>, <209>, <210>; 52*4882a593Smuzhiyun #mbox-cells = <1>; 53*4882a593Smuzhiyun }; 54*4882a593Smuzhiyun 55