From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-8.4 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 57254C352A3 for ; Mon, 10 Feb 2020 14:29:47 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 233832080C for ; Mon, 10 Feb 2020 14:29:47 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=ti.com header.i=@ti.com header.b="tS+Nt8nu" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728615AbgBJO3q (ORCPT ); Mon, 10 Feb 2020 09:29:46 -0500 Received: from lelv0142.ext.ti.com ([198.47.23.249]:57486 "EHLO lelv0142.ext.ti.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727481AbgBJO3q (ORCPT ); Mon, 10 Feb 2020 09:29:46 -0500 Received: from lelv0265.itg.ti.com ([10.180.67.224]) by lelv0142.ext.ti.com (8.15.2/8.15.2) with ESMTP id 01AESiJa001066; Mon, 10 Feb 2020 08:28:44 -0600 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ti.com; s=ti-com-17Q1; t=1581344924; bh=+SXU0yCFEep2Yqb8rENzdcMj11Yb5cRlMdNCjpmA0es=; h=Subject:To:CC:References:From:Date:In-Reply-To; b=tS+Nt8nunkUdVl31bfPwfP8vNDiDlnQ7sdnq6pQSgi9B6T/mjCojOHCYK44JPZUSy nOjGBg/NIsrH8km1yEQK39ovilB2UScjHjirOu3jlkSe27wN8f0MbR9cz4Z7dcIvsW byETDNkHXStoueFKplsWwUlKk3KgFEixlNS64gHk= Received: from DFLE100.ent.ti.com (dfle100.ent.ti.com [10.64.6.21]) by lelv0265.itg.ti.com (8.15.2/8.15.2) with ESMTPS id 01AESin6127867 (version=TLSv1.2 cipher=AES256-GCM-SHA384 bits=256 verify=FAIL); Mon, 10 Feb 2020 08:28:44 -0600 Received: from DFLE105.ent.ti.com (10.64.6.26) by DFLE100.ent.ti.com (10.64.6.21) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256_P256) id 15.1.1847.3; Mon, 10 Feb 2020 08:28:44 -0600 Received: from lelv0326.itg.ti.com (10.180.67.84) by DFLE105.ent.ti.com (10.64.6.26) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256_P256) id 15.1.1847.3 via Frontend Transport; Mon, 10 Feb 2020 08:28:44 -0600 Received: from [192.168.2.6] (ileax41-snat.itg.ti.com [10.172.224.153]) by lelv0326.itg.ti.com (8.15.2/8.15.2) with ESMTP id 01AESfmZ067868; Mon, 10 Feb 2020 08:28:42 -0600 Subject: Re: [PATCH] ASoC: dmaengine_pcm: Consider DMA cache caused delay in pointer callback To: Takashi Iwai CC: , , , , , , , References: <20200210140423.10232-1-peter.ujfalusi@ti.com> From: Peter Ujfalusi Message-ID: <15c7df10-cf9f-109c-3cbf-e73af7f4f66a@ti.com> Date: Mon, 10 Feb 2020 16:28:44 +0200 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.9.0 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset="utf-8" Content-Language: en-US Content-Transfer-Encoding: 8bit X-EXCLAIMER-MD-CONFIG: e1e8a2fd-e40a-4ac6-ac9b-f7e9cc9ee180 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Takashi, On 10/02/2020 16.21, Takashi Iwai wrote: > On Mon, 10 Feb 2020 15:04:23 +0100, > Peter Ujfalusi wrote: >> >> Some DMA engines can have big FIFOs which adds to the latency. >> The DMAengine framework can report the FIFO utilization in bytes. Use this >> information for the delay reporting. >> >> Signed-off-by: Peter Ujfalusi >> --- >> Hi, >> >> 5.6-rc1 now have support for reporting the DMA cached data. >> With this patch we can include it to the delay calculation. >> The first DMA driver which reports this is the TI K3 UDMA driver. >> >> Regards, >> Peter >> >> sound/core/pcm_dmaengine.c | 6 ++++++ >> sound/soc/soc-pcm.c | 2 +- >> 2 files changed, 7 insertions(+), 1 deletion(-) >> >> diff --git a/sound/core/pcm_dmaengine.c b/sound/core/pcm_dmaengine.c >> index 5749a8a49784..4f1395fd0160 100644 >> --- a/sound/core/pcm_dmaengine.c >> +++ b/sound/core/pcm_dmaengine.c >> @@ -247,9 +247,15 @@ snd_pcm_uframes_t snd_dmaengine_pcm_pointer(struct snd_pcm_substream *substream) >> >> status = dmaengine_tx_status(prtd->dma_chan, prtd->cookie, &state); >> if (status == DMA_IN_PROGRESS || status == DMA_PAUSED) { >> + struct snd_pcm_runtime *runtime = substream->runtime; >> + int sample_bits = snd_pcm_format_physical_width(runtime->format); >> + >> buf_size = snd_pcm_lib_buffer_bytes(substream); >> if (state.residue > 0 && state.residue <= buf_size) >> pos = buf_size - state.residue; >> + >> + sample_bits *= runtime->channels; >> + runtime->delay = state.in_flight_bytes / (sample_bits / 8); > > Can this be simply bytes_to_frames()? > > runtime->delay = bytes_to_frames(runtime, state.in_flight_bytes); Certainly it can, I looked at various helper but somehow missed the bytes_to_frames(). I'll send v2 in about an hour. > >> } >> >> return bytes_to_frames(substream->runtime, pos); >> diff --git a/sound/soc/soc-pcm.c b/sound/soc/soc-pcm.c >> index ff1b7c7078e5..58ef508d70a3 100644 >> --- a/sound/soc/soc-pcm.c >> +++ b/sound/soc/soc-pcm.c >> @@ -1151,7 +1151,7 @@ static snd_pcm_uframes_t soc_pcm_pointer(struct snd_pcm_substream *substream) >> } >> delay += codec_delay; >> >> - runtime->delay = delay; >> + runtime->delay += delay; > > Is it correct? > delay already takes runtime->delay as its basis, so it'll result in a > double. The delay here is coming from the DAI and the codec. The runtime->delay hold the PCM (DMA) caused delay. > > thanks, > > Takashi > - Péter Texas Instruments Finland Oy, Porkkalankatu 22, 00180 Helsinki. Y-tunnus/Business ID: 0615521-4. Kotipaikka/Domicile: Helsinki