From patchwork Mon Apr 10 11:21:02 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Sricharan Ramabadhran X-Patchwork-Id: 9672367 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 66CAB60244 for ; Mon, 10 Apr 2017 11:22:57 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 5BF3927F9A for ; Mon, 10 Apr 2017 11:22:57 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 50A7828111; Mon, 10 Apr 2017 11:22:57 +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=unavailable 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 CE05227F9A for ; Mon, 10 Apr 2017 11:22:56 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753531AbdDJLWl (ORCPT ); Mon, 10 Apr 2017 07:22:41 -0400 Received: from smtp.codeaurora.org ([198.145.29.96]:57606 "EHLO smtp.codeaurora.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753475AbdDJLWh (ORCPT ); Mon, 10 Apr 2017 07:22:37 -0400 Received: by smtp.codeaurora.org (Postfix, from userid 1000) id C5691600C5; Mon, 10 Apr 2017 11:22:35 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=codeaurora.org; s=default; t=1491823355; bh=Xcc3sVS5VDXXvrPNyyU4JK1B6BRw+5zn2IidTuwgHJg=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=VmE0N55kNGxNDYXtXqLtez9/RFJcb61oF6N99NZr+El1+aoynpk8br2WKwx2RF+DU uM9UJgt5G9VOBpkxINAa+9qA5mzQasRBm1vw0YJcuG8sC8mbW3cd1GwgOeEpRDPGUU /K11a6BWoY5LARhMW15jf2rxU/5ZQ023SSVcBLWE= 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 4F33560B72; Mon, 10 Apr 2017 11:22:26 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=codeaurora.org; s=default; t=1491823353; bh=Xcc3sVS5VDXXvrPNyyU4JK1B6BRw+5zn2IidTuwgHJg=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=aT06xb4q//n6AiJXof3qBKjs9aEXBc7TCeXLeK24pGgfahhs5RVqLC5fMFGtHT4WP xQNur3XuUau1h7ojnqSsIOUot+I0tQi4JdtqjGXPfx+4mH8lJlhmELUJItiD9kvq6E Hi3Pa7Yr68DtRA0me2QgmgTwvnQVgQDFu2ZHWYpM= DMARC-Filter: OpenDMARC Filter v1.3.2 smtp.codeaurora.org 4F33560B72 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, Laurent Pinchart Subject: [PATCH V11 07/11] iommu: of: Handle IOMMU lookup failure with deferred probing or error Date: Mon, 10 Apr 2017 16:51:02 +0530 Message-Id: <1491823266-1209-8-git-send-email-sricharan@codeaurora.org> X-Mailer: git-send-email 1.9.1 In-Reply-To: <1491823266-1209-1-git-send-email-sricharan@codeaurora.org> References: <1491823266-1209-1-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 Reviewed-by: Robin Murphy Acked-by: Rob Herring Signed-off-by: Laurent Pichart Signed-off-by: Sricharan R --- [V11] Small change to return non-void value in one of returns in of_dma_configure, as a result of dropping patch #3 from previous V10. No functional impact. drivers/base/dma-mapping.c | 5 +++-- drivers/iommu/of_iommu.c | 4 ++-- drivers/of/device.c | 9 +++++++-- include/linux/of_device.h | 9 ++++++--- 4 files changed, 18 insertions(+), 9 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 e1ae9e7..8bd3d8c 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; @@ -123,7 +123,7 @@ void of_dma_configure(struct device *dev, struct device_node *np) if (!size) { dev_err(dev, "Adjusted size 0x%llx invalid\n", size); - return; + return -EINVAL; } dev_dbg(dev, "dma_pfn_offset(%#08lx)\n", offset); } @@ -144,10 +144,15 @@ 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 */