Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1422932AbbENXAK (ORCPT ); Thu, 14 May 2015 19:00:10 -0400 Received: from galahad.ideasonboard.com ([185.26.127.97]:53985 "EHLO galahad.ideasonboard.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S964879AbbENXAG (ORCPT ); Thu, 14 May 2015 19:00:06 -0400 From: Laurent Pinchart To: linux-kernel@vger.kernel.org Cc: linux-arm-kernel@lists.infradead.org, iommu@lists.linux-foundation.org, Laura Abbott , Arnd Bergmann , Mitchel Humpherys , Joreg Roedel , Will Deacon , Grant Likely , Robin Murphy , Marek Szyprowski , Thierry Reding , Greg Kroah-Hartman Subject: [RFC/PATCH 1/9] arm: dma-mapping: Don't override dma_ops in arch_setup_dma_ops() Date: Fri, 15 May 2015 02:00:02 +0300 Message-Id: <1431644410-2997-2-git-send-email-laurent.pinchart+renesas@ideasonboard.com> X-Mailer: git-send-email 2.3.6 In-Reply-To: <1431644410-2997-1-git-send-email-laurent.pinchart+renesas@ideasonboard.com> References: <1431644410-2997-1-git-send-email-laurent.pinchart+renesas@ideasonboard.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1795 Lines: 51 The arch_setup_dma_ops() function is in charge of setting dma_ops with a call to set_dma_ops(). set_dma_ops() is also called from - highbank and mvebu bus notifiers - dmabounce (to be replaced with swiotlb) - arm_iommu_attach_device (arm_iommu_attach_device is itself called from IOMMU and bus master device drivers) To allow the arch_setup_dma_ops() call to be moved from device add time to device probe time we must ensure that dma_ops already setup by any of the above callers will not be overriden. Aftering replacing dmabounce with swiotlb, converting IOMMU drivers to of_xlate and taking care of highbank and mvebu, the workaround should be removed. Signed-off-by: Laurent Pinchart --- arch/arm/mm/dma-mapping.c | 9 +++++++++ 1 file changed, 9 insertions(+) diff --git a/arch/arm/mm/dma-mapping.c b/arch/arm/mm/dma-mapping.c index 09c5fe3d30c2..7aa5e339a596 100644 --- a/arch/arm/mm/dma-mapping.c +++ b/arch/arm/mm/dma-mapping.c @@ -2117,6 +2117,15 @@ void arch_setup_dma_ops(struct device *dev, u64 dma_base, u64 size, struct dma_map_ops *dma_ops; dev->archdata.dma_coherent = coherent; + + /* + * Don't override the dma_ops if they have already been set. Ideally + * this should be the only location where dma_ops are set, remove this + * check when all other callers of set_dma_ops will have disappeared. + */ + if (dev->archdata.dma_ops) + return; + if (arm_setup_iommu_dma_ops(dev, dma_base, size, iommu)) dma_ops = arm_get_iommu_dma_map_ops(coherent); else -- 2.3.6 -- 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/