From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933660AbdDELAM (ORCPT ); Wed, 5 Apr 2017 07:00:12 -0400 Received: from pandora.armlinux.org.uk ([78.32.30.218]:49694 "EHLO pandora.armlinux.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754896AbdDEK7J (ORCPT ); Wed, 5 Apr 2017 06:59:09 -0400 Date: Wed, 5 Apr 2017 11:58:41 +0100 From: Russell King - ARM Linux To: Lorenzo Pieralisi Cc: Bjorn Helgaas , linux-pci@vger.kernel.org, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, Arnd Bergmann , Will Deacon , Thomas Gleixner , Bjorn Helgaas , Richard Henderson , Tony Luck , Catalin Marinas , Ingo Molnar , Haavard Skinnemoen , Pratyush Anand , Jingoo Han , Mingkai Hu , John Garry , Tanmay Inamdar , Murali Karicheri , Bharat Kumar Gogada , Ray Jui , Wenrui Li , Shawn Lin , Minghuan Lian , Jon Mason , Gabriele Paoloni , Thomas Petazzoni , Joao Pinto , Thierry Reding , Michal Simek , Stanimir Varbanov , Zhou Wang , Roy Zang , "Luis R. Rodriguez" Subject: Re: [PATCH v2 02/22] asm-generic/io.h: add ioremap_nopost remap interface Message-ID: <20170405105841.GG7909@n2100.armlinux.org.uk> References: <20170327094954.7162-1-lorenzo.pieralisi@arm.com> <20170327094954.7162-3-lorenzo.pieralisi@arm.com> <20170328014110.GI25380@bhelgaas-glaptop.roam.corp.google.com> <20170328144543.GA18046@red-moon> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20170328144543.GA18046@red-moon> User-Agent: Mutt/1.5.23 (2014-03-12) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Mar 28, 2017 at 03:45:43PM +0100, Lorenzo Pieralisi wrote: > On Mon, Mar 27, 2017 at 08:41:10PM -0500, Bjorn Helgaas wrote: > > On Mon, Mar 27, 2017 at 10:49:30AM +0100, Lorenzo Pieralisi wrote: > > > diff --git a/arch/x86/include/asm/io.h b/arch/x86/include/asm/io.h > > > index 7afb0e2..50b292f 100644 > > > --- a/arch/x86/include/asm/io.h > > > +++ b/arch/x86/include/asm/io.h > > > @@ -171,6 +171,7 @@ static inline unsigned int isa_virt_to_bus(volatile void *address) > > > extern void __iomem *ioremap_nocache(resource_size_t offset, unsigned long size); > > > extern void __iomem *ioremap_uc(resource_size_t offset, unsigned long size); > > > #define ioremap_uc ioremap_uc > > > +#define ioremap_nopost ioremap_nocache > > > > These are all the same as the default from asm-generic.h. Do we really > > need these definitions in alpha, avr32, frv, ia64, x86? > > Those arches do not include asm-generic.h (I suppose for a good reason) > but a definition is needed anyway if we want code using ioremap_nopost() > to be unconditional. This is one way of doing it, there are others not > sure they are any better, I am open to suggestions. We do have linux/io.h, which should be included in preference to asm/io.h. linux/io.h has existed for years, but I still see (from time to time) patches adding drivers that (imho incorrectly) use asm/io.h. Also, this: > > > diff --git a/include/asm-generic/io.h b/include/asm-generic/io.h > > > index 7ef015e..0e81938 100644 > > > --- a/include/asm-generic/io.h > > > +++ b/include/asm-generic/io.h > > > @@ -915,6 +915,10 @@ extern void ioport_unmap(void __iomem *p); > > > #endif /* CONFIG_GENERIC_IOMAP */ > > > #endif /* CONFIG_HAS_IOPORT_MAP */ > > > > > > +#ifndef ioremap_nopost > > > +#define ioremap_nopost ioremap_nocache > > > +#endif > > > + > > > #ifndef xlate_dev_kmem_ptr > > > #define xlate_dev_kmem_ptr xlate_dev_kmem_ptr > > > static inline void *xlate_dev_kmem_ptr(void *addr) could well be located in linux/io.h, which would make it available everywhere. I'd suggest one change to this though: #ifndef ioremap_nopost static inline void __iomem *ioremap_nopost(resource_size_t offset, unsigned long size) { return ioremap_nocache(offset, size); } #endif This way, if someone forgets to define ioremap_nopost() in their asm/io.h but provides a definition or extern prototype for ioremap_nopost(), we end up with a compile error to highlight the error, rather than the error being hidden by the preprocessor. -- RMK's Patch system: http://www.armlinux.org.uk/developer/patches/ FTTC broadband for 0.8mile line: currently at 9.6Mbps down 400kbps up according to speedtest.net.