Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752494AbZGAG3y (ORCPT ); Wed, 1 Jul 2009 02:29:54 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1752100AbZGAG3q (ORCPT ); Wed, 1 Jul 2009 02:29:46 -0400 Received: from devils.ext.ti.com ([198.47.26.153]:57224 "EHLO devils.ext.ti.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751990AbZGAG3p convert rfc822-to-8bit (ORCPT ); Wed, 1 Jul 2009 02:29:45 -0400 From: "Gadiyar, Anand" To: "Gadiyar, Anand" , Jarkko Lavinen CC: "pierre@ossman.eu" , Tony Lindgren , "linux-kernel@vger.kernel.org" , "linux-omap@vger.kernel.org" Date: Wed, 1 Jul 2009 11:59:28 +0530 Subject: RE: [PATCH] OMAP: HSMMC: Do not enable buffer ready interrupt if using DMA Thread-Topic: [PATCH] OMAP: HSMMC: Do not enable buffer ready interrupt if using DMA Thread-Index: AcnNZ/m5/8MKE+GxRGWQOER2Yy6DygAuIxugAzEkNYAHy/GREA== Message-ID: <5A47E75E594F054BAF48C5E4FC4B92AB0305B783F3@dbde02.ent.ti.com> In-Reply-To: <5A47E75E594F054BAF48C5E4FC4B92AB03057422B4@dbde02.ent.ti.com> Accept-Language: en-US Content-Language: en-US X-MS-Has-Attach: X-MS-TNEF-Correlator: acceptlanguage: en-US Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 8BIT MIME-Version: 1.0 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1642 Lines: 51 On Fri, May 22, 2009, Gadiyar, Anand wrote: > On Wed, May 06, 2009, Gadiyar, Anand wrote: > > On Tue, May 5, 2009, Jarkko Lavinen wrote: > > > On Tue, Apr 21, 2009 at 09:39:22AM +0200, ext Gadiyar, Anand wrote: > > > > From: Anand Gadiyar > > > > > > > > OMAP: HSMMC: Do not enable buffer ready interrupt if using DMA > > > > > > > > This considerably reduces the number of interrupts during a transfer > > > > and ought to result in some power saving. > > > > > > I tried the patch with reading from the raw mmc block device to > > > /dev/null with dd (with bs 32k and 1M). I cannot see any > > > difference in interrupt count from /proc/interrupts or in read > > > speed. At least the patch works. Cpu was 34340es3. > > > > > > I also trid without the patch just disabling the Buffer > > > Read/write Ready bits from INT_EN_MASK which is then written to > > > both MMCHS_IE and MMCHS_ISE. Still no change in read speed nor > > > mmc irq count. > > > > > > Cheers > > > Jarkko Lavinen > > > > I discovered this while doing MMC writes. I did not check if there > > was any difference during a read. I notice you have only tested with > > MMC reads. > > > > Here's what I get with and without the patch. > > > > - Anand > > > Any comments on this? Is it safe to merge? > > Thanks, > Anand Ping? Patchwork link is: http://patchwork.kernel.org/patch/19133/ -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/