From mboxrd@z Thu Jan 1 00:00:00 1970 From: Roberto Fichera Subject: Re: fsl_ssi.c: Getting channel slips with fsl_ssi.c in TDM (network) mode. Date: Wed, 28 Oct 2015 09:23:01 +0100 Message-ID: <563085E5.1030401@tekno-soft.it> References: <5625EF02.30602@invoxia.com> <56273F75.2040702@invoxia.com> <20151027071344.GC25728@pengutronix.de> <20151027201101.GA9527@Asurada-CZ80> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Received: from mail.tekno-soft.it (li153-180.members.linode.com [109.74.206.180]) by alsa0.perex.cz (Postfix) with ESMTP id 7036F26044B for ; Wed, 28 Oct 2015 09:23:20 +0100 (CET) In-Reply-To: <20151027201101.GA9527@Asurada-CZ80> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: alsa-devel-bounces@alsa-project.org Sender: alsa-devel-bounces@alsa-project.org To: Nicolin Chen , Markus Pargmann Cc: Fabio Estevam , "alsa-devel@alsa-project.org" , "shawn.guo@linaro.org" , Caleb Crome , "arnaud.mouiche@invoxia.com" List-Id: alsa-devel@alsa-project.org On 10/27/2015 09:11 PM, Nicolin Chen wrote: > On Tue, Oct 27, 2015 at 08:13:44AM +0100, Markus Pargmann wrote: > >>> So, the dma priority doesn't seem to be the issue. It's now set in >>> the device tree, and strangely it's set to priority 0 (the highest) >>> along with the UARTS. priority 0 is just the highest in the device >>> tree -- it gets remapped to priority 3 in the sdma driver. the DT >>> exposes only 3 levels of DMA priority, low, medium, and high. I >>> created a new level that maps to DMA priroity 7 (the highest in the >>> hardware), but still got the problem. >>> >>> So, still something unknown causing dma to miss samples. must be in >>> the dma ISR I would assume. I guess it's time to look into that. >> Cc Nicolin, Fabio, Shawn >> >> Perhaps you have an idea about this? > Off the top of my head: > > 1) Enable TUE0, TUE1, ROE0, ROE1 to see if there is any IRQ trigged. I'm my case I was never able to see an interrupt triggered when setting both RDMAE and TDMAE bits in the SIER register. > 2) Set the watermarks for both TX and RX to 8 while using burst sizes > of 6. It'd be nicer to provisionally set these numbers using hard > code than your current change depending on fifo_depth as it might > be an odd value. > > 3) Try to enlarge the ALSA period size in the asound.conf or passing > parameters when you do the playback/capture so that the number of > interrupts from SDMA may reduce. > > You may also see if the reproducibility is somehow reduced or not. > > Nicolin > _______________________________________________ > Alsa-devel mailing list > Alsa-devel@alsa-project.org > http://mailman.alsa-project.org/mailman/listinfo/alsa-devel >