From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754342AbbJHJHd (ORCPT ); Thu, 8 Oct 2015 05:07:33 -0400 Received: from denmail01-v4020.amcc.com ([192.195.68.30]:59825 "EHLO denmail01.amcc.com" rhost-flags-OK-FAIL-OK-FAIL) by vger.kernel.org with ESMTP id S1752880AbbJHJHa (ORCPT ); Thu, 8 Oct 2015 05:07:30 -0400 From: Rameshwar Prasad Sahu To: vinod.koul@intel.com, dan.j.williams@intel.com Cc: dmaengine@vger.kernel.org, arnd@arndb.de, linux-kernel@vger.kernel.org, devicetree@vger.kernel.org, linux-arm-kernel@lists.infradead.org, jcm@redhat.com, patches@apm.com, Rameshwar Prasad Sahu Subject: [PATCH v2] dmaengine: xgene-dma: Disable memcpy operation due to performance drop Date: Thu, 8 Oct 2015 14:36:57 +0530 Message-Id: <1444295217-3099-1-git-send-email-rsahu@apm.com> X-Mailer: git-send-email 1.8.2.1 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org The DMA engine supports memory copy, RAID5 XOR, RAID6 PQ, and other computations. But the bandwidth of the entire DMA engine is shared among all channels. This patch re-configures operations availability such that one can achieve maximum performance for XOR and PQ computation by removing the memory offload operations. Signed-off-by: Rameshwar Prasad Sahu --- drivers/dma/xgene-dma.c | 1 - 1 file changed, 1 deletion(-) diff --git a/drivers/dma/xgene-dma.c b/drivers/dma/xgene-dma.c index 8d57b1b..cd38022 100644 --- a/drivers/dma/xgene-dma.c +++ b/drivers/dma/xgene-dma.c @@ -1707,7 +1707,6 @@ static void xgene_dma_set_caps(struct xgene_dma_chan *chan, dma_cap_zero(dma_dev->cap_mask); /* Set DMA device capability */ - dma_cap_set(DMA_MEMCPY, dma_dev->cap_mask); dma_cap_set(DMA_SG, dma_dev->cap_mask); /* Basically here, the X-Gene SoC DMA engine channel 0 supports XOR -- 1.8.2.1