Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S965624AbcJXSMy (ORCPT ); Mon, 24 Oct 2016 14:12:54 -0400 Received: from mga05.intel.com ([192.55.52.43]:28931 "EHLO mga05.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757581AbcJXSFv (ORCPT ); Mon, 24 Oct 2016 14:05:51 -0400 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.31,542,1473145200"; d="scan'208";a="23058755" Subject: [net-next PATCH RFC 09/26] arch/hexagon: Add option to skip DMA sync as a part of mapping From: Alexander Duyck To: netdev@vger.kernel.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org Cc: linux-hexagon@vger.kernel.org, brouer@redhat.com, davem@davemloft.net, Richard Kuo Date: Mon, 24 Oct 2016 08:05:14 -0400 Message-ID: <20161024120513.16276.39929.stgit@ahduyck-blue-test.jf.intel.com> In-Reply-To: <20161024115737.16276.71059.stgit@ahduyck-blue-test.jf.intel.com> References: <20161024115737.16276.71059.stgit@ahduyck-blue-test.jf.intel.com> User-Agent: StGit/0.17.1-dirty MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1205 Lines: 35 This change allows us to pass DMA_ATTR_SKIP_CPU_SYNC which allows us to avoid invoking cache line invalidation if the driver will just handle it later via a sync_for_cpu or sync_for_device call. Cc: Richard Kuo Cc: linux-hexagon@vger.kernel.org Signed-off-by: Alexander Duyck --- arch/hexagon/kernel/dma.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) diff --git a/arch/hexagon/kernel/dma.c b/arch/hexagon/kernel/dma.c index b901778..dbc4f10 100644 --- a/arch/hexagon/kernel/dma.c +++ b/arch/hexagon/kernel/dma.c @@ -119,6 +119,9 @@ static int hexagon_map_sg(struct device *hwdev, struct scatterlist *sg, s->dma_length = s->length; + if (attrs & DMA_ATTR_SKIP_CPU_SYNC) + continue; + flush_dcache_range(dma_addr_to_virt(s->dma_address), dma_addr_to_virt(s->dma_address + s->length)); } @@ -180,7 +183,8 @@ static dma_addr_t hexagon_map_page(struct device *dev, struct page *page, if (!check_addr("map_single", dev, bus, size)) return bad_dma_address; - dma_sync(dma_addr_to_virt(bus), size, dir); + if (!(attrs & DMA_ATTR_SKIP_CPU_SYNC)) + dma_sync(dma_addr_to_virt(bus), size, dir); return bus; }