Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752065AbaDANMn (ORCPT ); Tue, 1 Apr 2014 09:12:43 -0400 Received: from arroyo.ext.ti.com ([192.94.94.40]:35269 "EHLO arroyo.ext.ti.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751773AbaDANHF (ORCPT ); Tue, 1 Apr 2014 09:07:05 -0400 From: Peter Ujfalusi To: , , CC: , , , , , , Subject: [PATCH v2 08/14] DMA: edma: Use different eventq for cyclic channels Date: Tue, 1 Apr 2014 16:06:09 +0300 Message-ID: <1396357575-30585-9-git-send-email-peter.ujfalusi@ti.com> X-Mailer: git-send-email 1.9.1 In-Reply-To: <1396357575-30585-1-git-send-email-peter.ujfalusi@ti.com> References: <1396357575-30585-1-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 1dd9e8806975..10048b40fac8 100644 --- a/drivers/dma/edma.c +++ b/drivers/dma/edma.c @@ -628,6 +628,9 @@ 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); } -- 1.9.1 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/