From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753744AbaCMJTx (ORCPT ); Thu, 13 Mar 2014 05:19:53 -0400 Received: from devils.ext.ti.com ([198.47.26.153]:33046 "EHLO devils.ext.ti.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753713AbaCMJTs (ORCPT ); Thu, 13 Mar 2014 05:19:48 -0400 From: Peter Ujfalusi To: , , , , CC: , , Mark Brown , Liam Girdwood , Tony Lindgren , , Jyri Sarha , , , Subject: [PATCH 07/18] DMA: edma: Use different eventq for cyclic channels Date: Thu, 13 Mar 2014 11:18:29 +0200 Message-ID: <1394702320-21743-8-git-send-email-peter.ujfalusi@ti.com> X-Mailer: git-send-email 1.9.0 In-Reply-To: <1394702320-21743-1-git-send-email-peter.ujfalusi@ti.com> References: <1394702320-21743-1-git-send-email-peter.ujfalusi@ti.com> MIME-Version: 1.0 Content-Type: text/plain Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org To improve latency with cyclic DMA operation it is preferred to use different eventq/tc than the default which is used by all other drivers (mmc, spi, i2c, etc). When preparing the cyclic dma ask for non default queue for the channel which is going to be used with cyclic mode. Signed-off-by: Peter Ujfalusi --- drivers/dma/edma.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/drivers/dma/edma.c b/drivers/dma/edma.c index 86d6a3fb0d92..604c7c94c731 100644 --- a/drivers/dma/edma.c +++ b/drivers/dma/edma.c @@ -624,6 +624,9 @@ static struct dma_async_tx_descriptor *edma_prep_dma_cyclic( edesc->pset[i].opt |= TCINTEN; } + /* Use different eventq/tc for cyclic DMA to reduce latency */ + edma_request_non_default_queue(echan->ch_num); + return vchan_tx_prep(&echan->vchan, &edesc->vdesc, tx_flags); } -- 1.9.0