From patchwork Thu Oct 6 03:21:21 2016 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jeeja KP X-Patchwork-Id: 9363637 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id 4737F6075E for ; Thu, 6 Oct 2016 03:15:15 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 2DD4728DAF for ; Thu, 6 Oct 2016 03:15:15 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 2191728DB5; Thu, 6 Oct 2016 03:15:15 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-1.9 required=2.0 tests=BAYES_00, RCVD_IN_DNSWL_NONE autolearn=ham version=3.3.1 Received: from alsa0.perex.cz (alsa0.perex.cz [77.48.224.243]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 0B42728DAF for ; Thu, 6 Oct 2016 03:15:13 +0000 (UTC) Received: by alsa0.perex.cz (Postfix, from userid 1000) id 573092666EC; Thu, 6 Oct 2016 05:15:11 +0200 (CEST) Received: from alsa0.perex.cz (localhost [127.0.0.1]) by alsa0.perex.cz (Postfix) with ESMTP id ED11F26664F; Thu, 6 Oct 2016 05:12:46 +0200 (CEST) X-Original-To: alsa-devel@alsa-project.org Delivered-To: alsa-devel@alsa-project.org Received: by alsa0.perex.cz (Postfix, from userid 1000) id BB3822666C0; Thu, 6 Oct 2016 05:12:36 +0200 (CEST) Received: from mga05.intel.com (mga05.intel.com [192.55.52.43]) by alsa0.perex.cz (Postfix) with ESMTP id 0029E26655F for ; Thu, 6 Oct 2016 05:12:30 +0200 (CEST) Received: from fmsmga002.fm.intel.com ([10.253.24.26]) by fmsmga105.fm.intel.com with ESMTP; 05 Oct 2016 20:12:28 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos; i="5.31,451,1473145200"; d="scan'208"; a="1066742375" Received: from kpjeeja-desk.iind.intel.com ([10.223.96.110]) by fmsmga002.fm.intel.com with ESMTP; 05 Oct 2016 20:12:26 -0700 From: jeeja.kp@intel.com To: alsa-devel@alsa-project.org Date: Thu, 6 Oct 2016 08:51:21 +0530 Message-Id: <1475724081-15129-1-git-send-email-jeeja.kp@intel.com> X-Mailer: git-send-email 2.5.0 Cc: Dharageswari R , tiwai@suse.de, patches.audio@intel.com, broonie@kernel.org, liam.r.girdwood@intel.com, Jeeja KP Subject: [alsa-devel] [PATCH] ASoC: Intel: Skylake: Use DPIB to update position for Playback stream X-BeenThere: alsa-devel@alsa-project.org X-Mailman-Version: 2.1.14 Precedence: list List-Id: "Alsa-devel mailing list for ALSA developers - http://www.alsa-project.org" List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Errors-To: alsa-devel-bounces@alsa-project.org Sender: alsa-devel-bounces@alsa-project.org X-Virus-Scanned: ClamAV using ClamSMTP From: Dharageswari R DPIB is read currently from a buffer position in memory (indicated by the registers DPIB[U|L]BASE).Driver reads the position buffer on BDL completion interrupts to report the DMA position. But the BDL completion interrupt only indicates the last DMA transfer of the buffer is completed at the Intel HD Audio subsystem boundary. The periodic DMA Position-in-Buffer writes may be scheduled at the same time or later than the MSI and does not guarantee to reflect the position of the last buffer that was transferred. Whereas DPIB register in HDA space(vendor specific register indicated by SDxDPIB) reflects the actual data that is transferred. Hence update the position based on DPIB for playback. Signed-off-by: Dharageswari R Signed-off-by: Jeeja KP --- sound/soc/intel/skylake/skl-pcm.c | 18 ++++++++++++++++-- 1 file changed, 16 insertions(+), 2 deletions(-) diff --git a/sound/soc/intel/skylake/skl-pcm.c b/sound/soc/intel/skylake/skl-pcm.c index 9edf5ba..b2a067b 100644 --- a/sound/soc/intel/skylake/skl-pcm.c +++ b/sound/soc/intel/skylake/skl-pcm.c @@ -1053,10 +1053,24 @@ static snd_pcm_uframes_t skl_platform_pcm_pointer (struct snd_pcm_substream *substream) { struct hdac_ext_stream *hstream = get_hdac_ext_stream(substream); + struct hdac_ext_bus *ebus = get_bus_ctx(substream); unsigned int pos; - /* use the position buffer as default */ - pos = snd_hdac_stream_get_pos_posbuf(hdac_stream(hstream)); + /* + * Use DPIB for Playback stream as the periodic DMA Position-in- + * Buffer Writes may be scheduled at the same time or later than + * the MSI and does not guarantee to reflect the Position of the + * last buffer that was transferred. Whereas DPIB register in + * HAD space reflects the actual data that is transferred. + * Use the position buffer for capture, as DPIB write gets + * completed earlier than the actual data written to the DDR. + */ + if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) + pos = readl(ebus->bus.remap_addr + AZX_REG_VS_SDXDPIB_XBASE + + (AZX_REG_VS_SDXDPIB_XINTERVAL * + hdac_stream(hstream)->index)); + else + pos = snd_hdac_stream_get_pos_posbuf(hdac_stream(hstream)); if (pos >= hdac_stream(hstream)->bufsize) pos = 0;