From mboxrd@z Thu Jan 1 00:00:00 1970 From: alan@lxorguk.ukuu.org.uk (Alan Cox) Date: Tue, 11 Dec 2012 17:32:32 +0000 Subject: [RFC v1 01/16] lib: devres: don't enclose pcim_*() functions in CONFIG_HAS_IOPORT In-Reply-To: <20121211164608.GT14363@n2100.arm.linux.org.uk> References: <1354917879-32073-1-git-send-email-thomas.petazzoni@free-electrons.com> <201212111043.50627.arnd@arndb.de> <20121211170338.4859ddf0@skate> <201212111615.03262.arnd@arndb.de> <20121211173013.0ceea196@skate> <20121211164608.GT14363@n2100.arm.linux.org.uk> Message-ID: <20121211173232.43668ab3@pyramind.ukuu.org.uk> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org > with it. It's very simple. The IO port space is for ISA/PCMCIA and > PCI IO port regions. It is nothing more than that. And on a lot of devices the LPC bus. > Plus, if you _have_ IO space support, you must have some MMIO region for > them to target - doing what many platforms have done to date and targetted > ISA IO address 0 at virtual address 0 is just not on because as soon as > you build a device driver which probes ISA addresses into your kernel, > you will oops. There shouldn't really be anything poking around that is modern - this is true of some PC stuff too. In general however if its because you have a window partly mapped you could just catch the exception and load 0xFF for reads (and probably whine with a backtrace so you know who to moan at). Alan From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754250Ab2LKR1j (ORCPT ); Tue, 11 Dec 2012 12:27:39 -0500 Received: from lxorguk.ukuu.org.uk ([81.2.110.251]:60918 "EHLO lxorguk.ukuu.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753701Ab2LKR1h (ORCPT ); Tue, 11 Dec 2012 12:27:37 -0500 Date: Tue, 11 Dec 2012 17:32:32 +0000 From: Alan Cox To: Russell King - ARM Linux Cc: Thomas Petazzoni , Arnd Bergmann , Lior Amsalem , Andrew Lunn , Yehuda Yitschak , Maen Suleiman , Jason Cooper , Tawfik Bayouk , Stephen Warren , Thierry Reding , linux-kernel@vger.kernel.org, Jesse Barnes , Eran Ben-Avi , Nadav Haklai , Paul Gortmaker , Shadi Ammouri , Gregory Clement , Yinghai Lu , linux-arm-kernel@lists.infradead.org Subject: Re: [RFC v1 01/16] lib: devres: don't enclose pcim_*() functions in CONFIG_HAS_IOPORT Message-ID: <20121211173232.43668ab3@pyramind.ukuu.org.uk> In-Reply-To: <20121211164608.GT14363@n2100.arm.linux.org.uk> References: <1354917879-32073-1-git-send-email-thomas.petazzoni@free-electrons.com> <201212111043.50627.arnd@arndb.de> <20121211170338.4859ddf0@skate> <201212111615.03262.arnd@arndb.de> <20121211173013.0ceea196@skate> <20121211164608.GT14363@n2100.arm.linux.org.uk> X-Mailer: Claws Mail 3.8.1 (GTK+ 2.24.8; x86_64-redhat-linux-gnu) Face: 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 Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org > with it. It's very simple. The IO port space is for ISA/PCMCIA and > PCI IO port regions. It is nothing more than that. And on a lot of devices the LPC bus. > Plus, if you _have_ IO space support, you must have some MMIO region for > them to target - doing what many platforms have done to date and targetted > ISA IO address 0 at virtual address 0 is just not on because as soon as > you build a device driver which probes ISA addresses into your kernel, > you will oops. There shouldn't really be anything poking around that is modern - this is true of some PC stuff too. In general however if its because you have a window partly mapped you could just catch the exception and load 0xFF for reads (and probably whine with a backtrace so you know who to moan at). Alan