Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S942026AbcJFAUO (ORCPT ); Wed, 5 Oct 2016 20:20:14 -0400 Received: from gate.crashing.org ([63.228.1.57]:39963 "EHLO gate.crashing.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S934489AbcJFAUK (ORCPT ); Wed, 5 Oct 2016 20:20:10 -0400 Message-ID: <1475713112.3784.183.camel@kernel.crashing.org> Subject: Re: [PATCH V3 2/4] ARM64 LPC: LPC driver implementation on Hip06 From: Benjamin Herrenschmidt To: John Garry , Jon Masters , Arnd Bergmann , linux-arm-kernel@lists.infradead.org Cc: "zhichang.yuan" , devicetree@vger.kernel.org, lorenzo.pieralisi@arm.com, gabriele.paoloni@huawei.com, minyard@acm.org, gregkh@linuxfoundation.org, will.deacon@arm.com, linux-kernel@vger.kernel.org, xuwei5@hisilicon.com, linuxarm@huawei.com, linux-serial@vger.kernel.org, linux-pci@vger.kernel.org, zourongrong@gmail.com, liviu.dudau@arm.com, kantyzc@163.com, zhichang.yuan02@gmail.com Date: Thu, 06 Oct 2016 11:18:32 +1100 In-Reply-To: <6bbfeb57-7a55-6a3e-60b2-3f44525e5882@huawei.com> References: <1473855354-150093-1-git-send-email-yuanzhichang@hisilicon.com> <5140357.dcW9ibtZJ6@wuerfel> <57D963C4.4010406@hisilicon.com> <5869118.UilSPY9Sai@wuerfel> <2af4f2d8-e3a4-fa00-e700-60af70bf4560@jonmasters.org> <6bbfeb57-7a55-6a3e-60b2-3f44525e5882@huawei.com> Content-Type: text/plain; charset="UTF-8" X-Mailer: Evolution 3.20.5 (3.20.5-1.fc24) Mime-Version: 1.0 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 798 Lines: 20 On Tue, 2016-10-04 at 13:02 +0100, John Garry wrote: > Right, so I think Zhichang can make the necessary generic changes to  > 8250 OF driver to support IO port as well as MMIO-based. > > However an LPC-based earlycon driver is still required. > > A note on hip07-based D05 (for those unaware): this does not use  > LPC-based uart. It uses PL011. The hardware guys have managed some  > trickery where they loopback the serial line around the BMC/CPLD. But we  > still need it for hip06 D03 and any other boards which want to use LPC  > bus for uart. > > A question on SBSA: does it propose how to provide serial via BMC for SOL? Probably another reason to keep 8250 as a legal option ... The (very popular) Aspeed BMCs tend to do this via a 8250-looking virtual UART on LPC. Cheers, Ben,