From patchwork Tue Apr 4 10:18:21 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Sricharan Ramabadhran X-Patchwork-Id: 9661143 X-Patchwork-Delegate: bhelgaas@google.com Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id 8DD426032D for ; Tue, 4 Apr 2017 10:20:32 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 7E8A428307 for ; Tue, 4 Apr 2017 10:20:32 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 72DEE284D1; Tue, 4 Apr 2017 10:20:32 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.8 required=2.0 tests=BAYES_00,DKIM_SIGNED, RCVD_IN_DNSWL_HI,T_DKIM_INVALID autolearn=ham version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id BAD1228307 for ; Tue, 4 Apr 2017 10:20:31 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753079AbdDDKUX (ORCPT ); Tue, 4 Apr 2017 06:20:23 -0400 Received: from smtp.codeaurora.org ([198.145.29.96]:47406 "EHLO smtp.codeaurora.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753187AbdDDKT7 (ORCPT ); Tue, 4 Apr 2017 06:19:59 -0400 Received: by smtp.codeaurora.org (Postfix, from userid 1000) id 56C9460F6F; Tue, 4 Apr 2017 10:19:58 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=codeaurora.org; s=default; t=1491301198; bh=AixqJvgjkAjgG4Jk1v4MGoG0HlFtod6encDCc/uTaVA=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=gfUxdrPj73QXdz9HYbXU9oRDMEEny8h5z4HMMmDxPPwKbpWsZ7eRL5QF0BoY5h9Fw z6D/vR/tzmVpRxqVqqFRL80rFQZH+JpUH0z5bLVwv+yHIZ3sjS/o7pc5rbJnooCYBM TmViE8xB3SOflRoUXps8GFEG7xCR5g97Yjv4+Om8= Received: from srichara-linux.qualcomm.com (unknown [202.46.23.62]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-SHA256 (128/128 bits)) (No client certificate requested) (Authenticated sender: sricharan@smtp.codeaurora.org) by smtp.codeaurora.org (Postfix) with ESMTPSA id 3828E60E08; Tue, 4 Apr 2017 10:19:49 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=codeaurora.org; s=default; t=1491301197; bh=AixqJvgjkAjgG4Jk1v4MGoG0HlFtod6encDCc/uTaVA=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=kPY3OB+MB9meuD964ZzXyF6UPiytaJ+/t2SDGnyu+ObuiXt+tAUsZsZRd56NnTyzN iJh7xWvi6PdMHC0vMd4j0a3R4o/sqSDQsvBoOkNLEYiRvsw7mJePGKi6rvI+kItfNM lJ0ei0qleioZYMzMqgST+Py21F5wR/v7cMwDPFMg= DMARC-Filter: OpenDMARC Filter v1.3.2 smtp.codeaurora.org 3828E60E08 Authentication-Results: pdx-caf-mail.web.codeaurora.org; dmarc=none (p=none dis=none) header.from=codeaurora.org Authentication-Results: pdx-caf-mail.web.codeaurora.org; spf=none smtp.mailfrom=sricharan@codeaurora.org From: Sricharan R To: robin.murphy@arm.com, will.deacon@arm.com, joro@8bytes.org, lorenzo.pieralisi@arm.com, iommu@lists.linux-foundation.org, linux-arm-kernel@lists.infradead.org, linux-arm-msm@vger.kernel.org, m.szyprowski@samsung.com, bhelgaas@google.com, linux-pci@vger.kernel.org, linux-acpi@vger.kernel.org, tn@semihalf.com, hanjun.guo@linaro.org, okaya@codeaurora.org, robh+dt@kernel.org, frowand.list@gmail.com, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, sudeep.holla@arm.com, rjw@rjwysocki.net, lenb@kernel.org, catalin.marinas@arm.com, arnd@arndb.de, linux-arch@vger.kernel.org, gregkh@linuxfoundation.org Cc: sricharan@codeaurora.org Subject: [PATCH V10 08/12] iommu: of: Handle IOMMU lookup failure with deferred probing or error Date: Tue, 4 Apr 2017 15:48:21 +0530 Message-Id: <1491301105-5274-9-git-send-email-sricharan@codeaurora.org> X-Mailer: git-send-email 1.9.1 In-Reply-To: <1491301105-5274-1-git-send-email-sricharan@codeaurora.org> References: <1489086061-9356-1-git-send-email-sricharan@codeaurora.org> <1491301105-5274-1-git-send-email-sricharan@codeaurora.org> Sender: linux-pci-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-pci@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP From: Laurent Pinchart Failures to look up an IOMMU when parsing the DT iommus property need to be handled separately from the .of_xlate() failures to support deferred probing. The lack of a registered IOMMU can be caused by the lack of a driver for the IOMMU, the IOMMU device probe not having been performed yet, having been deferred, or having failed. The first case occurs when the device tree describes the bus master and IOMMU topology correctly but no device driver exists for the IOMMU yet or the device driver has not been compiled in. Return NULL, the caller will configure the device without an IOMMU. The second and third cases are handled by deferring the probe of the bus master device which will eventually get reprobed after the IOMMU. The last case is currently handled by deferring the probe of the bus master device as well. A mechanism to either configure the bus master device without an IOMMU or to fail the bus master device probe depending on whether the IOMMU is optional or mandatory would be a good enhancement. Tested-by: Marek Szyprowski Signed-off-by: Laurent Pichart Signed-off-by: Sricharan R Reviewed-by: Robin Murphy --- drivers/base/dma-mapping.c | 5 +++-- drivers/iommu/of_iommu.c | 4 ++-- drivers/of/device.c | 7 ++++++- include/linux/of_device.h | 9 ++++++--- 4 files changed, 17 insertions(+), 8 deletions(-) diff --git a/drivers/base/dma-mapping.c b/drivers/base/dma-mapping.c index 449b948..82bd45c 100644 --- a/drivers/base/dma-mapping.c +++ b/drivers/base/dma-mapping.c @@ -353,6 +353,7 @@ int dma_configure(struct device *dev) { struct device *bridge = NULL, *dma_dev = dev; enum dev_dma_attr attr; + int ret = 0; if (dev_is_pci(dev)) { bridge = pci_get_host_bridge_device(to_pci_dev(dev)); @@ -363,7 +364,7 @@ int dma_configure(struct device *dev) } if (dma_dev->of_node) { - of_dma_configure(dev, dma_dev->of_node); + ret = of_dma_configure(dev, dma_dev->of_node); } else if (has_acpi_companion(dma_dev)) { attr = acpi_get_dma_attr(to_acpi_device_node(dma_dev->fwnode)); if (attr != DEV_DMA_NOT_SUPPORTED) @@ -373,7 +374,7 @@ int dma_configure(struct device *dev) if (bridge) pci_put_host_bridge_device(bridge); - return 0; + return ret; } void dma_deconfigure(struct device *dev) diff --git a/drivers/iommu/of_iommu.c b/drivers/iommu/of_iommu.c index c8be889..9f44ee8 100644 --- a/drivers/iommu/of_iommu.c +++ b/drivers/iommu/of_iommu.c @@ -236,7 +236,7 @@ const struct iommu_ops *of_iommu_configure(struct device *dev, ops = ERR_PTR(err); } - return IS_ERR(ops) ? NULL : ops; + return ops; } static int __init of_iommu_init(void) @@ -247,7 +247,7 @@ static int __init of_iommu_init(void) for_each_matching_node_and_match(np, matches, &match) { const of_iommu_init_fn init_fn = match->data; - if (init_fn(np)) + if (init_fn && init_fn(np)) pr_err("Failed to initialise IOMMU %s\n", of_node_full_name(np)); } diff --git a/drivers/of/device.c b/drivers/of/device.c index c2ae6bb..bea8aec 100644 --- a/drivers/of/device.c +++ b/drivers/of/device.c @@ -82,7 +82,7 @@ int of_device_add(struct platform_device *ofdev) * can use a platform bus notifier and handle BUS_NOTIFY_ADD_DEVICE events * to fix up DMA configuration. */ -void of_dma_configure(struct device *dev, struct device_node *np) +int of_dma_configure(struct device *dev, struct device_node *np) { u64 dma_addr, paddr, size; int ret; @@ -129,10 +129,15 @@ void of_dma_configure(struct device *dev, struct device_node *np) coherent ? " " : " not "); iommu = of_iommu_configure(dev, np); + if (IS_ERR(iommu)) + return PTR_ERR(iommu); + dev_dbg(dev, "device is%sbehind an iommu\n", iommu ? " " : " not "); arch_setup_dma_ops(dev, dma_addr, size, iommu, coherent); + + return 0; } EXPORT_SYMBOL_GPL(of_dma_configure); diff --git a/include/linux/of_device.h b/include/linux/of_device.h index af98455..2cacdd8 100644 --- a/include/linux/of_device.h +++ b/include/linux/of_device.h @@ -55,7 +55,7 @@ static inline struct device_node *of_cpu_device_node_get(int cpu) return of_node_get(cpu_dev->of_node); } -void of_dma_configure(struct device *dev, struct device_node *np); +int of_dma_configure(struct device *dev, struct device_node *np); void of_dma_deconfigure(struct device *dev); #else /* CONFIG_OF */ @@ -104,8 +104,11 @@ static inline struct device_node *of_cpu_device_node_get(int cpu) { return NULL; } -static inline void of_dma_configure(struct device *dev, struct device_node *np) -{} + +static inline int of_dma_configure(struct device *dev, struct device_node *np) +{ + return 0; +} static inline void of_dma_deconfigure(struct device *dev) {} #endif /* CONFIG_OF */