Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753255AbcKRJYA (ORCPT ); Fri, 18 Nov 2016 04:24:00 -0500 Received: from mout.kundenserver.de ([212.227.126.134]:65407 "EHLO mout.kundenserver.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752758AbcKRJXy (ORCPT ); Fri, 18 Nov 2016 04:23:54 -0500 From: Arnd Bergmann To: linux-arm-kernel@lists.infradead.org Cc: One Thousand Gnomes , Mark Rutland , gabriele.paoloni@huawei.com, benh@kernel.crashing.org, will.deacon@arm.com, linuxarm@huawei.com, lorenzo.pieralisi@arm.com, xuwei5@hisilicon.com, linux-serial@vger.kernel.org, catalin.marinas@arm.com, devicetree@vger.kernel.org, minyard@acm.org, marc.zyngier@arm.com, liviu.dudau@arm.com, john.garry@huawei.com, zourongrong@gmail.com, robh+dt@kernel.org, bhelgaas@google.com, kantyzc@163.com, zhichang.yuan02@gmail.com, linux-pci@vger.kernel.org, linux-kernel@vger.kernel.org, "zhichang.yuan" , olof@lixom.net Subject: Re: [PATCH V5 2/3] ARM64 LPC: Add missing range exception for special ISA Date: Fri, 18 Nov 2016 10:22:46 +0100 Message-ID: <11716372.n451O5j8Vs@wuerfel> User-Agent: KMail/5.1.3 (Linux/4.4.0-34-generic; KDE/5.18.0; x86_64; ; ) In-Reply-To: <20161114111111.1b753dc3@lxorguk.ukuu.org.uk> References: <1478576829-112707-1-git-send-email-yuanzhichang@hisilicon.com> <5900275.i4NZvtxTcC@wuerfel> <20161114111111.1b753dc3@lxorguk.ukuu.org.uk> MIME-Version: 1.0 Content-Transfer-Encoding: 7Bit Content-Type: text/plain; charset="us-ascii" X-Provags-ID: V03:K0:arayQd7wlhNoLaBCZfWA8PcednQU32yky1dThMN+6hNsJYpxmOp cDPUABJi7tOEt4l1lNlIu7Ou0ZlpFwWdUoTVQbBn5Dgo1jXElA/tAt6JciEh+yVSGd2OHYK 0ePP6IZtp6oi13BDJn8qv7z8cOfUi6VcCNYry24ReawLBcQ2DQobLsgI/NVa1sUcRWY5URw G8eoBpBjJ1WRcIoR2EYWQ== X-UI-Out-Filterresults: notjunk:1;V01:K0:Aop14ieskeo=:e6DO/0nQ3hiQ3FjAwsKUxl m/GY05HxwfS5MejcFfrL6vbfmfz9YvYAhraQgX9rQferUd7X3vhEDiftke0VKsRyiULKUOygS gxIaepD0TRmYRIcU6FCnJDsEVgnb6iCxCmAvif4J8pbt4DsGP2SRiSnd/SfaQ2A2Nf3lXX8/B EmbtMVhVuhjR+XYkpi8qr0FB7LZe5C8rGA1IsnSIY06liwk4GJR1Qz+3+sA96cSVcYnFM5aNd Zo83TwkrfIx8oQ/dmc08cAgODYltzqQdJ3JIDXMqAtq+//7agYDSiDRpXICog3Jqf0NM/SjGd 54UFXXVhwBvln8i3RLwmH3hRgsWG4k4ECxxroaOI/79Yc9JLjBCDYTVJZaS2ttqytCsukRIPd 9/Av+hCeS8wPSFLrSsD/glL343k4/0GpJ1HsRQgUJm/kZ/uEfhlNumdFCWqslvnMxqM/bTN7D UG/4CvSYG7D3hKarKbYpqUJ0t/yG2u9KYhiRMsx82iH99GMGXZTOlwAcbWfxqR/osoLEMdhvb 4VYcPW3QLv6wVft+txhqxM1ApOOU4KuKMFwIW2awJLxvnra9VVD3YIniOoqj2U3DS3Acal1aS GqmeNUoiQDE4GAt50+0T+ZutoHT/kDKLZDSl2/SHxxBBD977H+9AG0p3w1tzwmaWrrp+XBXmj srVhqVUnskFI6e6DwfMSO1gX3yBFtMhwwvH53AQ4+lNeYnlpYNq+pqRSFn5XITLuTwxOO0OBf yD1dgii8Aic6LKne Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1145 Lines: 25 On Monday, November 14, 2016 11:11:11 AM CET One Thousand Gnomes wrote: > > > It's not a safe assumption for x86 at least. There are a few systems with > > > multiple ISA busses particularly older laptops with a docking station. > > > > But do they have multiple ISA domains? There is no real harm in supporting > > it, the (small) downsides I can think of are: > > I don't believe they x86 class ones have multiple ISA domains. But as > I've said I don't know how the electronics in the older ThinkPad worked > when it used two PIIX4s with some LPC or ISA stuff on each. > > It works in DOS and unmodified Linux so I'm pretty sure there are no > additional domains. Likewise the various x86 schemes that route some bits > of ISA bus off into strange places work in DOS and don't have any > overlaps. > > yenta_socket handles PCI/PCMCIA bridging and routes a range of that flat > ISA space appropriately to the card. Right, that's what I had expected, so we still don't even need to handle multiple ISA I/O address spaces for the only known case of multiple ISA buses, though we may decide to generalize the code like that anyway. Arnd