From mboxrd@z Thu Jan 1 00:00:00 1970 From: Arnd Bergmann Subject: Re: [PATCH v3 01/17] asm-generic: io: implement relaxed accessor macros as conditional wrappers Date: Thu, 25 Sep 2014 12:32 +0200 Message-ID: <4501051.vdxhyhkTWv@wuerfel> References: <1411579056-16966-1-git-send-email-will.deacon@arm.com> <1411579056-16966-2-git-send-email-will.deacon@arm.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7Bit Return-path: In-Reply-To: <1411579056-16966-2-git-send-email-will.deacon@arm.com> Sender: linux-kernel-owner@vger.kernel.org To: Will Deacon Cc: linux-arch@vger.kernel.org, linux-kernel@vger.kernel.org, benh@kernel.crashing.org, chris@zankel.net, cmetcalf@tilera.com, davem@davemloft.net, deller@gmx.de, dhowells@redhat.com, geert@linux-m68k.org, heiko.carstens@de.ibm.com, hpa@zytor.com, jcmvbkbc@gmail.com, jesper.nilsson@axis.com, mingo@redhat.com, monstr@monstr.eu, paulmck@linux.vnet.ibm.com, rdunlap@infradead.org, sam@ravnborg.org, schwidefsky@de.ibm.com, starvik@axis.com, takata@linux-m32r.org, tglx@linutronix.de, tony.luck@intel.com, daniel.thompson@linaro.org, broonie@linaro.org, linux@arm.linux.org.uk List-Id: linux-arch.vger.kernel.org On Wednesday 24 September 2014 18:17:20 Will Deacon wrote: > {read,write}{b,w,l,q}_relaxed are implemented by some architectures in > order to permit memory-mapped I/O accesses with weaker barrier semantics > than the non-relaxed variants. > > This patch adds wrappers to asm-generic so that drivers can rely on the > relaxed accessors being available, even if they don't always provide > weaker ordering guarantees. Since some architectures both include > asm-generic/io.h and define some relaxed accessors, the definitions here > are conditional for the time being. > > Cc: Arnd Bergmann > Signed-off-by: Will Deacon > --- > include/asm-generic/io.h | 26 ++++++++++++++++++++++++++ > 1 file changed, 26 insertions(+) > Acked-by: Arnd Bergmann From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mout.kundenserver.de ([212.227.126.130]:59581 "EHLO mout.kundenserver.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751895AbaIYKdI (ORCPT ); Thu, 25 Sep 2014 06:33:08 -0400 From: Arnd Bergmann Subject: Re: [PATCH v3 01/17] asm-generic: io: implement relaxed accessor macros as conditional wrappers Date: Thu, 25 Sep 2014 12:32 +0200 Message-ID: <4501051.vdxhyhkTWv@wuerfel> In-Reply-To: <1411579056-16966-2-git-send-email-will.deacon@arm.com> References: <1411579056-16966-1-git-send-email-will.deacon@arm.com> <1411579056-16966-2-git-send-email-will.deacon@arm.com> MIME-Version: 1.0 Content-Transfer-Encoding: 7Bit Content-Type: text/plain; charset="us-ascii" Sender: linux-arch-owner@vger.kernel.org List-ID: To: Will Deacon Cc: linux-arch@vger.kernel.org, linux-kernel@vger.kernel.org, benh@kernel.crashing.org, chris@zankel.net, cmetcalf@tilera.com, davem@davemloft.net, deller@gmx.de, dhowells@redhat.com, geert@linux-m68k.org, heiko.carstens@de.ibm.com, hpa@zytor.com, jcmvbkbc@gmail.com, jesper.nilsson@axis.com, mingo@redhat.com, monstr@monstr.eu, paulmck@linux.vnet.ibm.com, rdunlap@infradead.org, sam@ravnborg.org, schwidefsky@de.ibm.com, starvik@axis.com, takata@linux-m32r.org, tglx@linutronix.de, tony.luck@intel.com, daniel.thompson@linaro.org, broonie@linaro.org, linux@arm.linux.org.uk Message-ID: <20140925103200.bR89kUvHnnCG70JbXNv4S35ZaxkedppsI5CwSE5937w@z> On Wednesday 24 September 2014 18:17:20 Will Deacon wrote: > {read,write}{b,w,l,q}_relaxed are implemented by some architectures in > order to permit memory-mapped I/O accesses with weaker barrier semantics > than the non-relaxed variants. > > This patch adds wrappers to asm-generic so that drivers can rely on the > relaxed accessors being available, even if they don't always provide > weaker ordering guarantees. Since some architectures both include > asm-generic/io.h and define some relaxed accessors, the definitions here > are conditional for the time being. > > Cc: Arnd Bergmann > Signed-off-by: Will Deacon > --- > include/asm-generic/io.h | 26 ++++++++++++++++++++++++++ > 1 file changed, 26 insertions(+) > Acked-by: Arnd Bergmann