From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753961AbcANNMH (ORCPT ); Thu, 14 Jan 2016 08:12:07 -0500 Received: from mail-pf0-f193.google.com ([209.85.192.193]:36362 "EHLO mail-pf0-f193.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750828AbcANNMF (ORCPT ); Thu, 14 Jan 2016 08:12:05 -0500 Subject: Re: [PATCH v1 3/3] ARM64 LPC: update binding doc To: Benjamin Herrenschmidt , arnd@arndb.de, catalin.marinas@arm.com, will.deacon@arm.com References: <1451396032-23708-1-git-send-email-zourongrong@gmail.com> <1451396032-23708-4-git-send-email-zourongrong@gmail.com> <1452727756.2403.47.camel@kernel.crashing.org> <569701E3.2090307@gmail.com> <1452742757.31558.8.camel@kernel.crashing.org> <5697274C.1000606@gmail.com> <1452770755.31558.13.camel@kernel.crashing.org> Cc: lijianhua@huawei.com, lixiancai@huawei.com, linuxarm@huawei.com, linux-kernel@vger.kernel.org, minyard@acm.org, gregkh@linuxfoundation.org From: Rongrong Zou Message-ID: <56979E9D.3050202@gmail.com> Date: Thu, 14 Jan 2016 21:11:57 +0800 User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64; rv:38.0) Gecko/20100101 Thunderbird/38.5.0 MIME-Version: 1.0 In-Reply-To: <1452770755.31558.13.camel@kernel.crashing.org> Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 2016/1/14 19:25, Benjamin Herrenschmidt wrote: > On Thu, 2016-01-14 at 12:42 +0800, Rongrong Zou wrote: > >>> Right, and the "compatible" property should be something like the >>> specific implementation of the LPC bridge. For example, ibm,power8- >>> lpc >>> in my case. Not something generic. >>> >>> Maybe we could allow for a generic one if the LPC is directly MMIO >>> mapped via the ranges property. >> >> It is not directly MMIO mapped actually. > > I know yours is not. But some are. My point is that we should have a > binding that is either completely specific to your ARM64 LPC or we > should have a generic LPC binding with provisions for implementation > specific stuff such as ARM64 or POWER8 which are both not MMIO mapped. Yes, that is what I want, both mapped and unmapped IO should better be supported. > > I go for the latter. > > So "ranges" if you are mapped, otherwise "reg", and in the latter case, > the compatible property should be much more specific like it is for P8, > > .../... > >> The big problem is we do not want the "ranges" property, but we can't >> get resource if the property is absent, you could see discussion at >> https://lkml.org/lkml/2016/1/11/631. > > That's fixable. I missed the discussion but I'll have a look tomorrow. > > Cheers > Ben. > Regars, Rongrong