From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mx1.redhat.com ([209.132.183.28]:21073 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752377Ab1K3O37 (ORCPT ); Wed, 30 Nov 2011 09:29:59 -0500 Date: Wed, 30 Nov 2011 16:31:24 +0200 From: "Michael S. Tsirkin" To: Arnd Bergmann Cc: Chris Metcalf , Lucas De Marchi , Paul Mundt , Jesse Barnes , "David S. Miller" , linux-kernel@vger.kernel.org, linux-pci@vger.kernel.org, linux-arch@vger.kernel.org, Andrew Morton Subject: Re: [PATCH-RFC 1/2] tile: don't panic on iomap Message-ID: <20111130143122.GC21413@redhat.com> References: <201111300909.18431.arnd@arndb.de> <20111130115956.GA21413@redhat.com> <201111301404.41544.arnd@arndb.de> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii In-Reply-To: <201111301404.41544.arnd@arndb.de> Sender: linux-pci-owner@vger.kernel.org List-ID: On Wed, Nov 30, 2011 at 02:04:41PM +0000, Arnd Bergmann wrote: > On Wednesday 30 November 2011, Michael S. Tsirkin wrote: > > > > Presumably whoever wrote that architecture considered and discarded setting GENERIC_IOMAP. > > > > > > The tile PCI controller is apparently special in that it does not map the > > > PIO region into MMIO space, or make it available in any other way, so generic > > > iomap with IOCOND is pointless. Setting NO_IPORT will still mean that drivers > > > using ioport_map will not be built. This mostly impacts the legacy (non-AHCI) > > > ATA controllers, which I assume are not used on tile anyway. > > > > I don't object to setting NO_IPORT at all, but this won't help address > > the problem this patch is fixing, which is to use a generic pci_iomap > > on tile. > > Ah, right. I didn't realize that the generic pci_iomap still attempts > to call ioport_map(). It would probably make sense to enclose > the ioport_map() call in pci_iomap() inside of #ifdef CONFIG_HAS_IOPORT. > It's not exactly beautiful, but probably the most correct solution > so that we can make any call to ioport_map() a build-time error on > architectures that set CONFIG_NO_IOPORT. > > Arnd I'm not sure why do you want to do that. -- MST