From mboxrd@z Thu Jan 1 00:00:00 1970 From: Dmitry Osipenko Subject: Re: [PATCH v1] dmaengine: tegra: Use relaxed versions of readl/writel Date: Fri, 26 Apr 2019 15:19:22 +0300 Message-ID: <68c342e2-5662-5632-82aa-659da0381f54@gmail.com> References: <20190424231708.21219-1-digetx@gmail.com> <20190426120148.GB28103@vkoul-mobl> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 8bit Return-path: In-Reply-To: <20190426120148.GB28103@vkoul-mobl> Content-Language: en-US Sender: linux-kernel-owner@vger.kernel.org To: Vinod Koul Cc: Laxman Dewangan , Thierry Reding , Jonathan Hunter , dmaengine@vger.kernel.org, linux-tegra@vger.kernel.org, linux-kernel@vger.kernel.org List-Id: linux-tegra@vger.kernel.org 26.04.2019 15:01, Vinod Koul пишет: > 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 > Looks like you answered to a wrong email.