From patchwork Thu May 14 23:00:02 2015 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Laurent Pinchart X-Patchwork-Id: 6410341 Return-Path: X-Original-To: patchwork-linux-arm@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork1.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.29.136]) by patchwork1.web.kernel.org (Postfix) with ESMTP id 2C9389F1C1 for ; Thu, 14 May 2015 23:04:30 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 551632044C for ; Thu, 14 May 2015 23:04:29 +0000 (UTC) Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.9]) (using TLSv1.2 with cipher DHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 7C3DB20411 for ; Thu, 14 May 2015 23:04:28 +0000 (UTC) Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.80.1 #2 (Red Hat Linux)) id 1Yt27v-00059R-HK; Thu, 14 May 2015 23:01:15 +0000 Received: from galahad.ideasonboard.com ([185.26.127.97]) by bombadil.infradead.org with esmtps (Exim 4.80.1 #2 (Red Hat Linux)) id 1Yt27G-0004dj-8r for linux-arm-kernel@lists.infradead.org; Thu, 14 May 2015 23:00:35 +0000 Received: from avalon.ideasonboard.com (dsl-hkibrasgw3-50ddcc-40.dhcp.inet.fi [80.221.204.40]) by galahad.ideasonboard.com (Postfix) with ESMTPSA id 3C014203AB; Fri, 15 May 2015 01:00:02 +0200 (CEST) From: Laurent Pinchart To: linux-kernel@vger.kernel.org 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> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20150514_160034_466728_359DF61E X-CRM114-Status: GOOD ( 11.72 ) X-Spam-Score: -0.0 (/) Cc: Laura Abbott , Arnd Bergmann , Robin Murphy , Joreg Roedel , Will Deacon , iommu@lists.linux-foundation.org, Thierry Reding , Greg Kroah-Hartman , Grant Likely , Mitchel Humpherys , linux-arm-kernel@lists.infradead.org, Marek Szyprowski X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.18-1 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org X-Spam-Status: No, score=-4.2 required=5.0 tests=BAYES_00, RCVD_IN_DNSWL_MED, T_RP_MATCHES_RCVD, UNPARSEABLE_RELAY autolearn=unavailable version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP 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