18c2ecf20Sopenharmony_ci# SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause) 28c2ecf20Sopenharmony_ci# Copyright 2019 BayLibre, SAS 38c2ecf20Sopenharmony_ci%YAML 1.2 48c2ecf20Sopenharmony_ci--- 58c2ecf20Sopenharmony_ci$id: "http://devicetree.org/schemas/mailbox/amlogic,meson-gxbb-mhu.yaml#" 68c2ecf20Sopenharmony_ci$schema: "http://devicetree.org/meta-schemas/core.yaml#" 78c2ecf20Sopenharmony_ci 88c2ecf20Sopenharmony_cititle: Amlogic Meson Message-Handling-Unit Controller 98c2ecf20Sopenharmony_ci 108c2ecf20Sopenharmony_cimaintainers: 118c2ecf20Sopenharmony_ci - Neil Armstrong <narmstrong@baylibre.com> 128c2ecf20Sopenharmony_ci 138c2ecf20Sopenharmony_cidescription: | 148c2ecf20Sopenharmony_ci The Amlogic's Meson SoCs Message-Handling-Unit (MHU) is a mailbox controller 158c2ecf20Sopenharmony_ci that has 3 independent channels/links to communicate with remote processor(s). 168c2ecf20Sopenharmony_ci MHU links are hardwired on a platform. A link raises interrupt for any 178c2ecf20Sopenharmony_ci received data. However, there is no specified way of knowing if the sent 188c2ecf20Sopenharmony_ci data has been read by the remote. This driver assumes the sender polls 198c2ecf20Sopenharmony_ci STAT register and the remote clears it after having read the data. 208c2ecf20Sopenharmony_ci 218c2ecf20Sopenharmony_ciproperties: 228c2ecf20Sopenharmony_ci compatible: 238c2ecf20Sopenharmony_ci enum: 248c2ecf20Sopenharmony_ci - amlogic,meson-gxbb-mhu 258c2ecf20Sopenharmony_ci 268c2ecf20Sopenharmony_ci reg: 278c2ecf20Sopenharmony_ci maxItems: 1 288c2ecf20Sopenharmony_ci 298c2ecf20Sopenharmony_ci interrupts: 308c2ecf20Sopenharmony_ci minItems: 3 318c2ecf20Sopenharmony_ci description: 328c2ecf20Sopenharmony_ci Contains the interrupt information corresponding to each of the 3 links 338c2ecf20Sopenharmony_ci of MHU. 348c2ecf20Sopenharmony_ci 358c2ecf20Sopenharmony_ci "#mbox-cells": 368c2ecf20Sopenharmony_ci const: 1 378c2ecf20Sopenharmony_ci 388c2ecf20Sopenharmony_cirequired: 398c2ecf20Sopenharmony_ci - compatible 408c2ecf20Sopenharmony_ci - reg 418c2ecf20Sopenharmony_ci - interrupts 428c2ecf20Sopenharmony_ci - "#mbox-cells" 438c2ecf20Sopenharmony_ci 448c2ecf20Sopenharmony_ciadditionalProperties: false 458c2ecf20Sopenharmony_ci 468c2ecf20Sopenharmony_ciexamples: 478c2ecf20Sopenharmony_ci - | 488c2ecf20Sopenharmony_ci mailbox@c883c404 { 498c2ecf20Sopenharmony_ci compatible = "amlogic,meson-gxbb-mhu"; 508c2ecf20Sopenharmony_ci reg = <0xc883c404 0x4c>; 518c2ecf20Sopenharmony_ci interrupts = <208>, <209>, <210>; 528c2ecf20Sopenharmony_ci #mbox-cells = <1>; 538c2ecf20Sopenharmony_ci }; 548c2ecf20Sopenharmony_ci 55