From patchwork Tue Feb 16 21:54:02 2016 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Robert Jarzmik X-Patchwork-Id: 8332621 Return-Path: X-Original-To: patchwork-dmaengine@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork2.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.29.136]) by patchwork2.web.kernel.org (Postfix) with ESMTP id E49FDC02AA for ; Tue, 16 Feb 2016 21:54:27 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 1867120303 for ; Tue, 16 Feb 2016 21:54:27 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id D5130202E5 for ; Tue, 16 Feb 2016 21:54:25 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756199AbcBPVyZ (ORCPT ); Tue, 16 Feb 2016 16:54:25 -0500 Received: from smtp05.smtpout.orange.fr ([80.12.242.127]:42025 "EHLO smtp.smtpout.orange.fr" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756102AbcBPVyY (ORCPT ); Tue, 16 Feb 2016 16:54:24 -0500 Received: from belgarion.home ([109.220.94.162]) by mwinf5d52 with ME id K9u61s0053WBhcl039u81m; Tue, 16 Feb 2016 22:54:21 +0100 X-ME-Helo: belgarion.home X-ME-Date: Tue, 16 Feb 2016 22:54:21 +0100 X-ME-IP: 109.220.94.162 From: Robert Jarzmik To: Daniel Mack , Haojian Zhuang , Robert Jarzmik , Vinod Koul Cc: linux-arm-kernel@lists.infradead.org, dmaengine@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH v2] dmaengine: pxa_dma: fix cyclic transfers Date: Tue, 16 Feb 2016 22:54:02 +0100 Message-Id: <1455659642-7746-1-git-send-email-robert.jarzmik@free.fr> X-Mailer: git-send-email 2.1.4 Sender: dmaengine-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: dmaengine@vger.kernel.org X-Spam-Status: No, score=-6.9 required=5.0 tests=BAYES_00,FREEMAIL_FROM, RCVD_IN_DNSWL_HI, RP_MATCHES_RCVD, UNPARSEABLE_RELAY autolearn=ham version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP While testing audio with pxa2xx-ac97, underrun were happening while the user application was correctly feeding the music. Debug proved that the cyclic transfer is not cyclic, ie. the last descriptor did not loop on the first. Another issue is that the descriptor length was always set to 8192, because of an trivial operator issue. This was tested on a pxa27x platform. Fixes: a57e16cf0333 ("dmaengine: pxa: add pxa dmaengine driver") Reported-by: Vasily Khoruzhick Tested-by: Vasily Khoruzhick Signed-off-by: Robert Jarzmik --- Since v1: add the mask fix suggested by Vasily --- drivers/dma/pxa_dma.c | 8 +++++++- 1 file changed, 7 insertions(+), 1 deletion(-) diff --git a/drivers/dma/pxa_dma.c b/drivers/dma/pxa_dma.c index 8ab4a53e5660..77c1c44009d8 100644 --- a/drivers/dma/pxa_dma.c +++ b/drivers/dma/pxa_dma.c @@ -586,6 +586,8 @@ static void set_updater_desc(struct pxad_desc_sw *sw_desc, (PXA_DCMD_LENGTH & sizeof(u32)); if (flags & DMA_PREP_INTERRUPT) updater->dcmd |= PXA_DCMD_ENDIRQEN; + if (sw_desc->cyclic) + sw_desc->hw_desc[sw_desc->nb_desc - 2]->ddadr = sw_desc->first; } static bool is_desc_completed(struct virt_dma_desc *vd) @@ -676,6 +678,10 @@ static irqreturn_t pxad_chan_handler(int irq, void *dev_id) dev_dbg(&chan->vc.chan.dev->device, "%s(): checking txd %p[%x]: completed=%d\n", __func__, vd, vd->tx.cookie, is_desc_completed(vd)); + if (to_pxad_sw_desc(vd)->cyclic) { + vchan_cyclic_callback(vd); + break; + } if (is_desc_completed(vd)) { list_del(&vd->node); vchan_cookie_complete(vd); @@ -1084,7 +1090,7 @@ pxad_prep_dma_cyclic(struct dma_chan *dchan, return NULL; pxad_get_config(chan, dir, &dcmd, &dsadr, &dtadr); - dcmd |= PXA_DCMD_ENDIRQEN | (PXA_DCMD_LENGTH | period_len); + dcmd |= PXA_DCMD_ENDIRQEN | (PXA_DCMD_LENGTH & period_len); dev_dbg(&chan->vc.chan.dev->device, "%s(): buf_addr=0x%lx len=%zu period=%zu dir=%d flags=%lx\n", __func__, (unsigned long)buf_addr, len, period_len, dir, flags);