From mboxrd@z Thu Jan 1 00:00:00 1970 From: Arnd Bergmann Subject: Re: [PATCH 4/7] io-64-nonatomic: Add relaxed accessor variants Date: Mon, 25 Apr 2016 17:41:21 +0200 Message-ID: <4658440.AyDy7GFvoa@wuerfel> References: <5485134.l18Z1dlVmn@wuerfel> <571E3781.3070609@arm.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <571E3781.3070609-5wv7dgnIgG8@public.gmane.org> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: iommu-bounces-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org Errors-To: iommu-bounces-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org To: Robin Murphy Cc: Hitoshi Mitake , Will Deacon , Christoph Hellwig , iommu-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org, tchalamarla-M3mlKVOIwJVv6pq1l3V1OdBPR1lH4CV8@public.gmane.org, brian.starkey-5wv7dgnIgG8@public.gmane.org, linux-arm-kernel-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org, Darren Hart List-Id: iommu@lists.linux-foundation.org On Monday 25 April 2016 16:28:01 Robin Murphy wrote: > >>> > >>> We _could_ - indeed I started doing that, but then decided that the > >>> obfuscation of horrible macro-templated functions wasn't worth saving a > >>> couple of hundred bytes in some code that isn't exactly difficult to > >>> maintain and has needed touching once in 4 years. > >>> > >>> If you did want to go down the macro route, I may as well also generate both > >>> lo-hi and hi-lo headers all from a single template, it'd be really clever... > >>> > >> > >> I certainly wasn't suggesting any more than the obvious macroisation, > >> but I'll leave it up to Arnd, as I think this falls on his lap. > > > > I'd prefer the open-coded variant as well. > > By that, do you mean sticking with the smmu_writeq() implementation in > the driver and dropping this patch, or merging this patch as-is without > further macro-magic? > Sorry, that was really ambiguous on my end. I meant leaving patch 4/7 as it is in the version you posted. However, leaving the open-coded writel_relaxed() in the driver or just using the non-relaxed hi_lo_readq() would be totally fine too. Arnd From mboxrd@z Thu Jan 1 00:00:00 1970 From: arnd@arndb.de (Arnd Bergmann) Date: Mon, 25 Apr 2016 17:41:21 +0200 Subject: [PATCH 4/7] io-64-nonatomic: Add relaxed accessor variants In-Reply-To: <571E3781.3070609@arm.com> References: <5485134.l18Z1dlVmn@wuerfel> <571E3781.3070609@arm.com> Message-ID: <4658440.AyDy7GFvoa@wuerfel> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On Monday 25 April 2016 16:28:01 Robin Murphy wrote: > >>> > >>> We _could_ - indeed I started doing that, but then decided that the > >>> obfuscation of horrible macro-templated functions wasn't worth saving a > >>> couple of hundred bytes in some code that isn't exactly difficult to > >>> maintain and has needed touching once in 4 years. > >>> > >>> If you did want to go down the macro route, I may as well also generate both > >>> lo-hi and hi-lo headers all from a single template, it'd be really clever... > >>> > >> > >> I certainly wasn't suggesting any more than the obvious macroisation, > >> but I'll leave it up to Arnd, as I think this falls on his lap. > > > > I'd prefer the open-coded variant as well. > > By that, do you mean sticking with the smmu_writeq() implementation in > the driver and dropping this patch, or merging this patch as-is without > further macro-magic? > Sorry, that was really ambiguous on my end. I meant leaving patch 4/7 as it is in the version you posted. However, leaving the open-coded writel_relaxed() in the driver or just using the non-relaxed hi_lo_readq() would be totally fine too. Arnd