From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752874AbeDJJZl (ORCPT ); Tue, 10 Apr 2018 05:25:41 -0400 Received: from mail-wm0-f66.google.com ([74.125.82.66]:40651 "EHLO mail-wm0-f66.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752084AbeDJJZj (ORCPT ); Tue, 10 Apr 2018 05:25:39 -0400 X-Google-Smtp-Source: AIpwx49rTMI++sckt/AZYeiLMLQ70oQOF5PpmMJZjSUVZ8Ldxq9RvlncFcW0Nz2mLlpDishitsR/9g== Subject: Re: [PATCH] mtd: spi-nor: cadence-quadspi: Add DMA support for direct mode reads To: Vignesh R Cc: Brian Norris , Boris Brezillon , linux-mtd@lists.infradead.org, linux-kernel@vger.kernel.org, Linux ARM Mailing List References: <20180410081910.858-1-vigneshr@ti.com> From: Marek Vasut Message-ID: <70777773-8ade-bd42-e75a-6d5d9c3e50a2@gmail.com> Date: Tue, 10 Apr 2018 11:21:03 +0200 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:52.0) Gecko/20100101 Thunderbird/52.6.0 MIME-Version: 1.0 In-Reply-To: <20180410081910.858-1-vigneshr@ti.com> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 04/10/2018 10:19 AM, Vignesh R wrote: > Add support to use DMA over memory mapped reads in direct mode. This > helps in reducing CPU usage from ~100% to ~10% when reading data from > flash. For non-DMA'able/vmalloc'd buffers, driver just falls back to CPU > based memcpy. > > Signed-off-by: Vignesh R Reviewed-by: Marek Vasut -- Best regards, Marek Vasut