From mboxrd@z Thu Jan 1 00:00:00 1970 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: base64 Subject: [v1] dmaengine: tegra: Use relaxed versions of readl/writel From: Vinod Koul Message-Id: <20190426120148.GB28103@vkoul-mobl> Date: Fri, 26 Apr 2019 17:31:48 +0530 To: Dmitry Osipenko Cc: Laxman Dewangan , Thierry Reding , Jonathan Hunter , dmaengine@vger.kernel.org, linux-tegra@vger.kernel.org, linux-kernel@vger.kernel.org List-ID: T24gMjUtMDQtMTksIDAyOjE3LCBEbWl0cnkgT3NpcGVua28gd3JvdGU6Cj4gVGhlIHJlYWRsL3dy aXRlbCBmdW5jdGlvbnMgYXJlIGluc2VydGluZyBtZW1vcnkgYmFycmllciBpbiBvcmRlciB0bwo+ IGVuc3VyZSB0aGF0IG1lbW9yeSBzdG9yZXMgYXJlIGNvbXBsZXRlZC4gT24gVGVncmEyMCBhbmQg VGVncmEzMCB0aGlzCj4gcmVzdWx0cyBpbiBMMiBjYWNoZSBzeW5jaW5nIHdoaWNoIGlzbid0IGEg Y2hlYXBlc3Qgb3BlcmF0aW9uLiBUaGUKPiB0ZWdyYTIwLWFwYi1kbWEgZHJpdmVyIGRvZXNuJ3Qg bmVlZCB0byBzeW5jaHJvbml6ZSBnZW5lcmljIG1lbW9yeQo+IGFjY2Vzc2VzLCBoZW5jZSB1c2Ug dGhlIHJlbGF4ZWQgdmVyc2lvbnMgb2YgdGhlIGZ1bmN0aW9ucy4KClN1YnN5c3RlbSBuYW1lIGlz ICoqZG1hZW5naW5lKiogbm90IGRtYSEgUGxlYXNlIGZpeCB0aGF0Cg== From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-2.6 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,MAILING_LIST_MULTI,SPF_PASS,T_DKIMWL_WL_HIGH,USER_AGENT_MUTT autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 4F124C43219 for ; Fri, 26 Apr 2019 12:01:55 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 1AFA4206C1 for ; Fri, 26 Apr 2019 12:01:55 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1556280115; bh=Vowjtrv0OJqv16TygegnL2eNyyqR0noN1UiGX25yQ5M=; h=Date:From:To:Cc:Subject:References:In-Reply-To:List-ID:From; b=0czmq88f22V7+UllQTZBOGG+YLaRAwA4cEl+SlNlz0HBPvBPB0Q/0NZzUBbp4eeCk fSp31EW5iyFL2YVhLEmptOaR0Q5risBT6qTpOYsWhNMI2/Jy6zAlObr052CMgBkqX/ Ah89dFY6CqRVO2hP3LIfR2UwxcafcotHY7V+1nlg= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726050AbfDZMBy (ORCPT ); Fri, 26 Apr 2019 08:01:54 -0400 Received: from mail.kernel.org ([198.145.29.99]:49942 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726048AbfDZMBy (ORCPT ); Fri, 26 Apr 2019 08:01:54 -0400 Received: from localhost (unknown [171.76.113.243]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 469ED206C1; Fri, 26 Apr 2019 12:01:53 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1556280114; bh=Vowjtrv0OJqv16TygegnL2eNyyqR0noN1UiGX25yQ5M=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=1FJxFm9yyGkW7/V4pU3/CJBWNf1kfnlus8LFDwz7yzcUTAO0hM6LSqYL4QLkYNkhb /uVaRnSnzFrdalkqxNTV2rBeUpKeeC1Y/tjEgt+3Py+viXjnqub3wkGFgrKSWkFJaL Gr/tGF2AVfx21Bal8t39J8Xe16y8NzM4cWsS76L0= Date: Fri, 26 Apr 2019 17:31:48 +0530 From: Vinod Koul To: Dmitry Osipenko Cc: Laxman Dewangan , Thierry Reding , Jonathan Hunter , dmaengine@vger.kernel.org, linux-tegra@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH v1] dmaengine: tegra: Use relaxed versions of readl/writel Message-ID: <20190426120148.GB28103@vkoul-mobl> References: <20190424231708.21219-1-digetx@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset="UTF-8" Content-Disposition: inline In-Reply-To: <20190424231708.21219-1-digetx@gmail.com> User-Agent: Mutt/1.11.3 (2019-02-01) Sender: dmaengine-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: dmaengine@vger.kernel.org Message-ID: <20190426120148.fQEESqwtE5Q-7O7PcOnU4X0-DGxdwrBbR-ZrpBuMb_c@z> On 25-04-19, 02:17, Dmitry Osipenko wrote: > The readl/writel functions are inserting memory barrier in order to > ensure that memory stores are completed. On Tegra20 and Tegra30 this > results in L2 cache syncing which isn't a cheapest operation. The > tegra20-apb-dma driver doesn't need to synchronize generic memory > accesses, hence use the relaxed versions of the functions. Subsystem name is **dmaengine** not dma! Please fix that -- ~Vinod