Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S964797AbbKDJ6Z (ORCPT ); Wed, 4 Nov 2015 04:58:25 -0500 Received: from relay1.mentorg.com ([192.94.38.131]:39284 "EHLO relay1.mentorg.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932339AbbKDJ6X (ORCPT ); Wed, 4 Nov 2015 04:58:23 -0500 From: Sanjeev Sharma To: , , CC: , , Sanjeev Sharma Subject: [PATCH] ARM:dma-mapping: Handle DMA_BIDIRECTIONAL in _dma_page_cpu_to_dev() Date: Wed, 4 Nov 2015 15:26:48 +0530 Message-ID: <1446631008-5854-1-git-send-email-sanjeev_sharma@mentor.com> X-Mailer: git-send-email 1.7.11.7 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 Content-Length: 1646 Lines: 49 _dma_page_cpu_to_dev() treat DMA_BIDIRECTIONAL similar to DMA_TO_DEVICE which means that destination buffer is device memory,means cpu may have written some data to source buffer and data may be in cache line.For cleaner operation we need to call outer_flush_range() which will clean and invalidate outer cache lines. Signed-off-by: Sanjeev Sharma --- arch/arm/mm/dma-mapping.c | 18 +++++++++++++----- 1 file changed, 13 insertions(+), 5 deletions(-) diff --git a/arch/arm/mm/dma-mapping.c b/arch/arm/mm/dma-mapping.c index e62400e..e195235 100644 --- a/arch/arm/mm/dma-mapping.c +++ b/arch/arm/mm/dma-mapping.c @@ -850,12 +850,20 @@ static void __dma_page_cpu_to_dev(struct page *page, unsigned long off, dma_cache_maint_page(page, off, size, dir, dmac_map_area); paddr = page_to_phys(page) + off; - if (dir == DMA_FROM_DEVICE) { - outer_inv_range(paddr, paddr + size); - } else { - outer_clean_range(paddr, paddr + size); + + switch (dir) { + case DMA_FROM_DEVICE: + outer_inv_range(paddr, paddr + size); + break; + case DMA_TO_DEVICE: + outer_clean_range(paddr, paddr + size); + break; + case DMA_BIDIRECTIONAL: + outer_flush_range(paddr, paddr + size); + break; + default: + break; } - /* FIXME: non-speculating: flush on bidirectional mappings? */ } static void __dma_page_dev_to_cpu(struct page *page, unsigned long off, -- 1.7.11.7 -- 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/