From patchwork Thu Sep 4 16:50:00 2014 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Will Deacon X-Patchwork-Id: 4847291 Return-Path: X-Original-To: patchwork-linux-arm@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork2.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.19.201]) by patchwork2.web.kernel.org (Postfix) with ESMTP id C215CC0338 for ; Thu, 4 Sep 2014 17:08:10 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 4F9C520200 for ; Thu, 4 Sep 2014 17:08:01 +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 34B2C201E4 for ; Thu, 4 Sep 2014 17:08:00 +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 1XPaTc-0001h1-7j; Thu, 04 Sep 2014 17:05:40 +0000 Received: from cam-admin0.cambridge.arm.com ([217.140.96.50]) by bombadil.infradead.org with esmtp (Exim 4.80.1 #2 (Red Hat Linux)) id 1XPaEh-0002bN-A7 for linux-arm-kernel@lists.infradead.org; Thu, 04 Sep 2014 16:50:16 +0000 Received: from edgewater-inn.cambridge.arm.com (edgewater-inn.cambridge.arm.com [10.1.203.34]) by cam-admin0.cambridge.arm.com (8.12.6/8.12.6) with ESMTP id s84Gniwo014711; Thu, 4 Sep 2014 17:49:44 +0100 (BST) Received: by edgewater-inn.cambridge.arm.com (Postfix, from userid 1000) id B29911AE02A2; Thu, 4 Sep 2014 17:50:08 +0100 (BST) From: Will Deacon To: iommu@lists.linuxfoundation.org Subject: [PATCH 2/7] iommu/arm-smmu: add support for multi-master iommu groups Date: Thu, 4 Sep 2014 17:50:00 +0100 Message-Id: <1409849405-17347-3-git-send-email-will.deacon@arm.com> X-Mailer: git-send-email 2.1.0 In-Reply-To: <1409849405-17347-1-git-send-email-will.deacon@arm.com> References: <1409849405-17347-1-git-send-email-will.deacon@arm.com> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20140904_095015_760051_196F957A X-CRM114-Status: GOOD ( 19.54 ) X-Spam-Score: -6.7 (------) Cc: Will Deacon , tchalamarla@cavium.com, robin.murphy@arm.com, joro@8bytes.org, linux-arm-kernel@lists.infradead.org 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=-3.5 required=5.0 tests=BAYES_00, RCVD_IN_DNSWL_NONE, 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 Whilst the driver currently creates one IOMMU group per device, this will soon change when we start supporting non-transparent PCI bridges which require all upstream masters to be assigned to the same address space. This patch reworks our IOMMU group code so that we can easily support multi-master groups. The master configuration (streamids and smrs) is stored as private iommudata on the group, whilst the low-level attach/detach code is updated to avoid double alloc/free when dealing with multiple masters sharing the same SMMU configuration. This unifies device handling, regardless of whether the device sits on the platform or pci bus. Signed-off-by: Will Deacon --- drivers/iommu/arm-smmu.c | 62 ++++++++++++++++++++++++++---------------------- 1 file changed, 34 insertions(+), 28 deletions(-) diff --git a/drivers/iommu/arm-smmu.c b/drivers/iommu/arm-smmu.c index 958ae8194afe..ef6623dbba9a 100644 --- a/drivers/iommu/arm-smmu.c +++ b/drivers/iommu/arm-smmu.c @@ -431,17 +431,17 @@ static void parse_driver_options(struct arm_smmu_device *smmu) } while (arm_smmu_options[++i].opt); } -static struct device *dev_get_master_dev(struct device *dev) +static struct device_node *dev_get_dev_node(struct device *dev) { if (dev_is_pci(dev)) { struct pci_bus *bus = to_pci_dev(dev)->bus; while (!pci_is_root_bus(bus)) bus = bus->parent; - return bus->bridge->parent; + return bus->bridge->parent->of_node; } - return dev; + return dev->of_node; } static struct arm_smmu_master *find_smmu_master(struct arm_smmu_device *smmu, @@ -466,15 +466,10 @@ static struct arm_smmu_master *find_smmu_master(struct arm_smmu_device *smmu, } static struct arm_smmu_master_cfg * -find_smmu_master_cfg(struct arm_smmu_device *smmu, struct device *dev) +find_smmu_master_cfg(struct device *dev) { - struct arm_smmu_master *master; - - if (dev_is_pci(dev)) - return dev->archdata.iommu; - - master = find_smmu_master(smmu, dev->of_node); - return master ? &master->cfg : NULL; + struct iommu_group *group = iommu_group_get(dev); + return group ? iommu_group_get_iommudata(group) : NULL; } static int insert_smmu_master(struct arm_smmu_device *smmu, @@ -550,7 +545,7 @@ static struct arm_smmu_device *find_smmu_for_device(struct device *dev) { struct arm_smmu_device *smmu; struct arm_smmu_master *master = NULL; - struct device_node *dev_node = dev_get_master_dev(dev)->of_node; + struct device_node *dev_node = dev_get_dev_node(dev); spin_lock(&arm_smmu_devices_lock); list_for_each_entry(smmu, &arm_smmu_devices, list) { @@ -1156,9 +1151,10 @@ static int arm_smmu_domain_add_master(struct arm_smmu_domain *smmu_domain, struct arm_smmu_device *smmu = smmu_domain->smmu; void __iomem *gr0_base = ARM_SMMU_GR0(smmu); + /* Devices in an IOMMU group may already be configured */ ret = arm_smmu_master_configure_smrs(smmu, cfg); if (ret) - return ret; + return ret == -EEXIST ? 0 : ret; for (i = 0; i < cfg->num_streamids; ++i) { u32 idx, s2cr; @@ -1179,6 +1175,10 @@ static void arm_smmu_domain_remove_master(struct arm_smmu_domain *smmu_domain, struct arm_smmu_device *smmu = smmu_domain->smmu; void __iomem *gr0_base = ARM_SMMU_GR0(smmu); + /* An IOMMU group is torn down by the first device to be removed */ + if ((smmu->features & ARM_SMMU_FEAT_STREAM_MATCH) && !cfg->smrs) + return; + /* * We *must* clear the S2CR first, because freeing the SMR means * that it can be re-allocated immediately. @@ -1200,7 +1200,7 @@ static int arm_smmu_attach_dev(struct iommu_domain *domain, struct device *dev) struct arm_smmu_device *smmu, *dom_smmu; struct arm_smmu_master_cfg *cfg; - smmu = dev_get_master_dev(dev)->archdata.iommu; + smmu = find_smmu_for_device(dev); if (!smmu) { dev_err(dev, "cannot attach to SMMU, is it on the same bus?\n"); return -ENXIO; @@ -1228,7 +1228,7 @@ static int arm_smmu_attach_dev(struct iommu_domain *domain, struct device *dev) } /* Looks ok, so add the device to the domain */ - cfg = find_smmu_master_cfg(smmu_domain->smmu, dev); + cfg = find_smmu_master_cfg(dev); if (!cfg) return -ENODEV; @@ -1240,7 +1240,7 @@ static void arm_smmu_detach_dev(struct iommu_domain *domain, struct device *dev) struct arm_smmu_domain *smmu_domain = domain->priv; struct arm_smmu_master_cfg *cfg; - cfg = find_smmu_master_cfg(smmu_domain->smmu, dev); + cfg = find_smmu_master_cfg(dev); if (cfg) arm_smmu_domain_remove_master(smmu_domain, cfg); } @@ -1554,17 +1554,19 @@ static int __arm_smmu_get_pci_sid(struct pci_dev *pdev, u16 alias, void *data) return 0; /* Continue walking */ } +static void __arm_smmu_release_pci_iommudata(void *data) +{ + kfree(data); +} + static int arm_smmu_add_device(struct device *dev) { struct arm_smmu_device *smmu; + struct arm_smmu_master_cfg *cfg; struct iommu_group *group; + void (*releasefn)(void *) = NULL; int ret; - if (dev->archdata.iommu) { - dev_warn(dev, "IOMMU driver already assigned to device\n"); - return -EINVAL; - } - smmu = find_smmu_for_device(dev); if (!smmu) return -ENODEV; @@ -1576,7 +1578,6 @@ static int arm_smmu_add_device(struct device *dev) } if (dev_is_pci(dev)) { - struct arm_smmu_master_cfg *cfg; struct pci_dev *pdev = to_pci_dev(dev); cfg = kzalloc(sizeof(*cfg), GFP_KERNEL); @@ -1592,11 +1593,20 @@ static int arm_smmu_add_device(struct device *dev) */ pci_for_each_dma_alias(pdev, __arm_smmu_get_pci_sid, &cfg->streamids[0]); - dev->archdata.iommu = cfg; + releasefn = __arm_smmu_release_pci_iommudata; } else { - dev->archdata.iommu = smmu; + struct arm_smmu_master *master; + + master = find_smmu_master(smmu, dev->of_node); + if (!master) { + ret = -ENODEV; + goto out_put_group; + } + + cfg = &master->cfg; } + iommu_group_set_iommudata(group, cfg, releasefn); ret = iommu_group_add_device(group, dev); out_put_group: @@ -1606,10 +1616,6 @@ out_put_group: static void arm_smmu_remove_device(struct device *dev) { - if (dev_is_pci(dev)) - kfree(dev->archdata.iommu); - - dev->archdata.iommu = NULL; iommu_group_remove_device(dev); }