From mboxrd@z Thu Jan 1 00:00:00 1970 From: Troy Kisky Subject: Re: [PATCH V1 11/11] ASoC: DaVinci: pcm, fix underruns by using sram Date: Tue, 07 Jul 2009 12:21:22 -0700 Message-ID: <4A53A032.6030205@boundarydevices.com> References: <1246761001-21982-5-git-send-email-troy.kisky@boundarydevices.com> <1246761001-21982-6-git-send-email-troy.kisky@boundarydevices.com> <1246761001-21982-7-git-send-email-troy.kisky@boundarydevices.com> <1246761001-21982-8-git-send-email-troy.kisky@boundarydevices.com> <1246761001-21982-9-git-send-email-troy.kisky@boundarydevices.com> <1246761001-21982-10-git-send-email-troy.kisky@boundarydevices.com> <1246761001-21982-11-git-send-email-troy.kisky@boundarydevices.com> <1246761001-21982-12-git-send-email-troy.kisky@boundarydevices.com> <20090705130352.GE5334@sirena.org.uk> <4A52A081.9070003@boundarydevices.com> <20090707093132.GB14393@rakim.wolfsonmicro.main> <4A539CDE.20508@boundarydevices.com> <4A539E89.5090907@boundarydevices.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Received: from smtpauth01.csee.onr.siteprotect.com (smtpauth01.csee.onr.siteprotect.com [64.26.60.145]) by alsa0.perex.cz (Postfix) with ESMTP id 2980D24450 for ; Tue, 7 Jul 2009 21:21:24 +0200 (CEST) In-Reply-To: <4A539E89.5090907@boundarydevices.com> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: alsa-devel-bounces@alsa-project.org Errors-To: alsa-devel-bounces@alsa-project.org To: Mark Brown Cc: alsa-devel@alsa-project.org, davinci-linux-open-source@linux.davincidsp.com List-Id: alsa-devel@alsa-project.org Troy Kisky wrote: > Troy Kisky wrote: >> Mark Brown wrote: >> >> Even when using SDRAM, there is still another advantage to double buffering. >> That is tolerating very long interrupt latency on dma completion. The current >> code sets up the next periods dma transfer on dma completion. This could easily >> lead to underruns. So, even in this case, I think double buffering is worth >> the extra dma engine copy. >> > I overstated my case, it still would not "easily" happen. In fact, I now agree with you :^) Thanks Troy