1 files changed, 128 insertions, 170 deletions

diff --git a/drivers/iommu/arm-smmu-v3.c b/drivers/iommu/arm-smmu-v3.c
index d7fef5f99bfc..15ba80db6465 100644
--- a/drivers/iommu/arm-smmu-v3.c
+++ b/drivers/iommu/arm-smmu-v3.c
@@ -30,6 +30,7 @@
 #include <linux/msi.h>
 #include <linux/of.h>
 #include <linux/of_address.h>
+#include <linux/of_iommu.h>
 #include <linux/of_platform.h>
 #include <linux/pci.h>
 #include <linux/platform_device.h>
@@ -610,12 +611,9 @@ struct arm_smmu_device {
 	struct arm_smmu_strtab_cfg	strtab_cfg;
 };
 
-/* SMMU private data for an IOMMU group */
-struct arm_smmu_group {
+/* SMMU private data for each master */
+struct arm_smmu_master_data {
 	struct arm_smmu_device		*smmu;
-	struct arm_smmu_domain		*domain;
-	int				num_sids;
-	u32				*sids;
 	struct arm_smmu_strtab_ent	ste;
 };
 
@@ -1555,20 +1553,6 @@ static int arm_smmu_domain_finalise(struct iommu_domain *domain)
 	return ret;
 }
 
-static struct arm_smmu_group *arm_smmu_group_get(struct device *dev)
-{
-	struct iommu_group *group;
-	struct arm_smmu_group *smmu_group;
-
-	group = iommu_group_get(dev);
-	if (!group)
-		return NULL;
-
-	smmu_group = iommu_group_get_iommudata(group);
-	iommu_group_put(group);
-	return smmu_group;
-}
-
 static __le64 *arm_smmu_get_step_for_sid(struct arm_smmu_device *smmu, u32 sid)
 {
 	__le64 *step;
@@ -1591,27 +1575,17 @@ static __le64 *arm_smmu_get_step_for_sid(struct arm_smmu_device *smmu, u32 sid)
 	return step;
 }
 
-static int arm_smmu_install_ste_for_group(struct arm_smmu_group *smmu_group)
+static int arm_smmu_install_ste_for_dev(struct iommu_fwspec *fwspec)
 {
 	int i;
-	struct arm_smmu_domain *smmu_domain = smmu_group->domain;
-	struct arm_smmu_strtab_ent *ste = &smmu_group->ste;
-	struct arm_smmu_device *smmu = smmu_group->smmu;
-
-	if (smmu_domain->stage == ARM_SMMU_DOMAIN_S1) {
-		ste->s1_cfg = &smmu_domain->s1_cfg;
-		ste->s2_cfg = NULL;
-		arm_smmu_write_ctx_desc(smmu, ste->s1_cfg);
-	} else {
-		ste->s1_cfg = NULL;
-		ste->s2_cfg = &smmu_domain->s2_cfg;
-	}
+	struct arm_smmu_master_data *master = fwspec->iommu_priv;
+	struct arm_smmu_device *smmu = master->smmu;
 
-	for (i = 0; i < smmu_group->num_sids; ++i) {
-		u32 sid = smmu_group->sids[i];
+	for (i = 0; i < fwspec->num_ids; ++i) {
+		u32 sid = fwspec->ids[i];
 		__le64 *step = arm_smmu_get_step_for_sid(smmu, sid);
 
-		arm_smmu_write_strtab_ent(smmu, sid, step, ste);
+		arm_smmu_write_strtab_ent(smmu, sid, step, &master->ste);
 	}
 
 	return 0;
@@ -1619,13 +1593,11 @@ static int arm_smmu_install_ste_for_group(struct arm_smmu_group *smmu_group)
 
 static void arm_smmu_detach_dev(struct device *dev)
 {
-	struct arm_smmu_group *smmu_group = arm_smmu_group_get(dev);
+	struct arm_smmu_master_data *master = dev->iommu_fwspec->iommu_priv;
 
-	smmu_group->ste.bypass = true;
-	if (arm_smmu_install_ste_for_group(smmu_group) < 0)
+	master->ste.bypass = true;
+	if (arm_smmu_install_ste_for_dev(dev->iommu_fwspec) < 0)
 		dev_warn(dev, "failed to install bypass STE\n");
-
-	smmu_group->domain = NULL;
 }
 
 static int arm_smmu_attach_dev(struct iommu_domain *domain, struct device *dev)
@@ -1633,16 +1605,20 @@ static int arm_smmu_attach_dev(struct iommu_domain *domain, struct device *dev)
 	int ret = 0;
 	struct arm_smmu_device *smmu;
 	struct arm_smmu_domain *smmu_domain = to_smmu_domain(domain);
-	struct arm_smmu_group *smmu_group = arm_smmu_group_get(dev);
+	struct arm_smmu_master_data *master;
+	struct arm_smmu_strtab_ent *ste;
 
-	if (!smmu_group)
+	if (!dev->iommu_fwspec)
 		return -ENOENT;
 
+	master = dev->iommu_fwspec->iommu_priv;
+	smmu = master->smmu;
+	ste = &master->ste;
+
 	/* Already attached to a different domain? */
-	if (smmu_group->domain && smmu_group->domain != smmu_domain)
+	if (!ste->bypass)
 		arm_smmu_detach_dev(dev);
 
-	smmu = smmu_group->smmu;
 	mutex_lock(&smmu_domain->init_mutex);
 
 	if (!smmu_domain->smmu) {
@@ -1661,21 +1637,21 @@ static int arm_smmu_attach_dev(struct iommu_domain *domain, struct device *dev)
 		goto out_unlock;
 	}
 
-	/* Group already attached to this domain? */
-	if (smmu_group->domain)
-		goto out_unlock;
-
-	smmu_group->domain	= smmu_domain;
+	ste->bypass = false;
+	ste->valid = true;
 
-	/*
-	 * FIXME: This should always be "false" once we have IOMMU-backed
-	 * DMA ops for all devices behind the SMMU.
-	 */
-	smmu_group->ste.bypass	= domain->type == IOMMU_DOMAIN_DMA;
+	if (smmu_domain->stage == ARM_SMMU_DOMAIN_S1) {
+		ste->s1_cfg = &smmu_domain->s1_cfg;
+		ste->s2_cfg = NULL;
+		arm_smmu_write_ctx_desc(smmu, ste->s1_cfg);
+	} else {
+		ste->s1_cfg = NULL;
+		ste->s2_cfg = &smmu_domain->s2_cfg;
+	}
 
-	ret = arm_smmu_install_ste_for_group(smmu_group);
+	ret = arm_smmu_install_ste_for_dev(dev->iommu_fwspec);
 	if (ret < 0)
-		smmu_group->domain = NULL;
+		ste->valid = false;
 
 out_unlock:
 	mutex_unlock(&smmu_domain->init_mutex);
@@ -1734,40 +1710,19 @@ arm_smmu_iova_to_phys(struct iommu_domain *domain, dma_addr_t iova)
 	return ret;
 }
 
-static int __arm_smmu_get_pci_sid(struct pci_dev *pdev, u16 alias, void *sidp)
-{
-	*(u32 *)sidp = alias;
-	return 0; /* Continue walking */
-}
+static struct platform_driver arm_smmu_driver;
 
-static void __arm_smmu_release_pci_iommudata(void *data)
+static int arm_smmu_match_node(struct device *dev, void *data)
 {
-	kfree(data);
+	return dev->of_node == data;
 }
 
-static struct arm_smmu_device *arm_smmu_get_for_pci_dev(struct pci_dev *pdev)
+static struct arm_smmu_device *arm_smmu_get_by_node(struct device_node *np)
 {
-	struct device_node *of_node;
-	struct platform_device *smmu_pdev;
-	struct arm_smmu_device *smmu = NULL;
-	struct pci_bus *bus = pdev->bus;
-
-	/* Walk up to the root bus */
-	while (!pci_is_root_bus(bus))
-		bus = bus->parent;
-
-	/* Follow the "iommus" phandle from the host controller */
-	of_node = of_parse_phandle(bus->bridge->parent->of_node, "iommus", 0);
-	if (!of_node)
-		return NULL;
-
-	/* See if we can find an SMMU corresponding to the phandle */
-	smmu_pdev = of_find_device_by_node(of_node);
-	if (smmu_pdev)
-		smmu = platform_get_drvdata(smmu_pdev);
-
-	of_node_put(of_node);
-	return smmu;
+	struct device *dev = driver_find_device(&arm_smmu_driver.driver, NULL,
+						np, arm_smmu_match_node);
+	put_device(dev);
+	return dev ? dev_get_drvdata(dev) : NULL;
 }
 
 static bool arm_smmu_sid_in_range(struct arm_smmu_device *smmu, u32 sid)
@@ -1780,94 +1735,74 @@ static bool arm_smmu_sid_in_range(struct arm_smmu_device *smmu, u32 sid)
 	return sid < limit;
 }
 
+static struct iommu_ops arm_smmu_ops;
+
 static int arm_smmu_add_device(struct device *dev)
 {
 	int i, ret;
-	u32 sid, *sids;
-	struct pci_dev *pdev;
-	struct iommu_group *group;
-	struct arm_smmu_group *smmu_group;
 	struct arm_smmu_device *smmu;
+	struct arm_smmu_master_data *master;
+	struct iommu_fwspec *fwspec = dev->iommu_fwspec;
+	struct iommu_group *group;
 
-	/* We only support PCI, for now */
-	if (!dev_is_pci(dev))
+	if (!fwspec || fwspec->ops != &arm_smmu_ops)
 		return -ENODEV;
-
-	pdev = to_pci_dev(dev);
-	group = iommu_group_get_for_dev(dev);
-	if (IS_ERR(group))
-		return PTR_ERR(group);
-
-	smmu_group = iommu_group_get_iommudata(group);
-	if (!smmu_group) {
-		smmu = arm_smmu_get_for_pci_dev(pdev);
-		if (!smmu) {
-			ret = -ENOENT;
-			goto out_remove_dev;
-		}
-
-		smmu_group = kzalloc(sizeof(*smmu_group), GFP_KERNEL);
-		if (!smmu_group) {
-			ret = -ENOMEM;
-			goto out_remove_dev;
-		}
-
-		smmu_group->ste.valid	= true;
-		smmu_group->smmu	= smmu;
-		iommu_group_set_iommudata(group, smmu_group,
-					  __arm_smmu_release_pci_iommudata);
+	/*
+	 * We _can_ actually withstand dodgy bus code re-calling add_device()
+	 * without an intervening remove_device()/of_xlate() sequence, but
+	 * we're not going to do so quietly...
+	 */
+	if (WARN_ON_ONCE(fwspec->iommu_priv)) {
+		master = fwspec->iommu_priv;
+		smmu = master->smmu;
 	} else {
-		smmu = smmu_group->smmu;
+		smmu = arm_smmu_get_by_node(to_of_node(fwspec->iommu_fwnode));
+		if (!smmu)
+			return -ENODEV;
+		master = kzalloc(sizeof(*master), GFP_KERNEL);
+		if (!master)
+			return -ENOMEM;
+
+		master->smmu = smmu;
+		fwspec->iommu_priv = master;
 	}
 
-	/* Assume SID == RID until firmware tells us otherwise */
-	pci_for_each_dma_alias(pdev, __arm_smmu_get_pci_sid, &sid);
-	for (i = 0; i < smmu_group->num_sids; ++i) {
-		/* If we already know about this SID, then we're done */
-		if (smmu_group->sids[i] == sid)
-			goto out_put_group;
-	}
+	/* Check the SIDs are in range of the SMMU and our stream table */
+	for (i = 0; i < fwspec->num_ids; i++) {
+		u32 sid = fwspec->ids[i];
 
-	/* Check the SID is in range of the SMMU and our stream table */
-	if (!arm_smmu_sid_in_range(smmu, sid)) {
-		ret = -ERANGE;
-		goto out_remove_dev;
-	}
-
-	/* Ensure l2 strtab is initialised */
-	if (smmu->features & ARM_SMMU_FEAT_2_LVL_STRTAB) {
-		ret = arm_smmu_init_l2_strtab(smmu, sid);
-		if (ret)
-			goto out_remove_dev;
-	}
+		if (!arm_smmu_sid_in_range(smmu, sid))
+			return -ERANGE;
 
-	/* Resize the SID array for the group */
-	smmu_group->num_sids++;
-	sids = krealloc(smmu_group->sids, smmu_group->num_sids * sizeof(*sids),
-			GFP_KERNEL);
-	if (!sids) {
-		smmu_group->num_sids--;
-		ret = -ENOMEM;
-		goto out_remove_dev;
+		/* Ensure l2 strtab is initialised */
+		if (smmu->features & ARM_SMMU_FEAT_2_LVL_STRTAB) {
+			ret = arm_smmu_init_l2_strtab(smmu, sid);
+			if (ret)
+				return ret;
+		}
 	}
 
-	/* Add the new SID */
-	sids[smmu_group->num_sids - 1] = sid;
-	smmu_group->sids = sids;
-
-out_put_group:
-	iommu_group_put(group);
-	return 0;
+	group = iommu_group_get_for_dev(dev);
+	if (!IS_ERR(group))
+		iommu_group_put(group);
 
-out_remove_dev:
-	iommu_group_remove_device(dev);
-	iommu_group_put(group);
-	return ret;
+	return PTR_ERR_OR_ZERO(group);
 }
 
 static void arm_smmu_remove_device(struct device *dev)
 {
+	struct iommu_fwspec *fwspec = dev->iommu_fwspec;
+	struct arm_smmu_master_data *master;
+
+	if (!fwspec || fwspec->ops != &arm_smmu_ops)
+		return;
+
+	master = fwspec->iommu_priv;
+	if (master && master->ste.valid)
+		arm_smmu_detach_dev(dev);
 	iommu_group_remove_device(dev);
+	kfree(master);
+	iommu_fwspec_free(dev);
 }
 
 static int arm_smmu_domain_get_attr(struct iommu_domain *domain,
@@ -1914,6 +1849,15 @@ out_unlock:
 	return ret;
 }
 
+static int arm_smmu_of_xlate(struct device *dev, struct of_phandle_args *args)
+{
+	/* We only support PCI, for now */
+	if (!dev_is_pci(dev))
+		return -ENODEV;
+
+	return iommu_fwspec_add_ids(dev, args->args, 1);
+}
+
 static struct iommu_ops arm_smmu_ops = {
 	.capable		= arm_smmu_capable,
 	.domain_alloc		= arm_smmu_domain_alloc,
@@ -1928,6 +1872,7 @@ static struct iommu_ops arm_smmu_ops = {
 	.device_group		= pci_device_group,
 	.domain_get_attr	= arm_smmu_domain_get_attr,
 	.domain_set_attr	= arm_smmu_domain_set_attr,
+	.of_xlate		= arm_smmu_of_xlate,
 	.pgsize_bitmap		= -1UL, /* Restricted during device attach */
 };
 
@@ -2662,7 +2607,14 @@ static int arm_smmu_device_dt_probe(struct platform_device *pdev)
 	platform_set_drvdata(pdev, smmu);
 
 	/* Reset the device */
-	return arm_smmu_device_reset(smmu, bypass);
+	ret = arm_smmu_device_reset(smmu, bypass);
+	if (ret)
+		return ret;
+
+	/* And we're up. Go go go! */
+	of_iommu_set_ops(dev->of_node, &arm_smmu_ops);
+	pci_request_acs();
+	return bus_set_iommu(&pci_bus_type, &arm_smmu_ops);
 }
 
 static int arm_smmu_device_remove(struct platform_device *pdev)
@@ -2690,22 +2642,14 @@ static struct platform_driver arm_smmu_driver = {
 
 static int __init arm_smmu_init(void)
 {
-	struct device_node *np;
-	int ret;
-
-	np = of_find_matching_node(NULL, arm_smmu_of_match);
-	if (!np)
-		return 0;
-
-	of_node_put(np);
-
-	ret = platform_driver_register(&arm_smmu_driver);
-	if (ret)
-		return ret;
-
-	pci_request_acs();
+	static bool registered;
+	int ret = 0;
 
-	return bus_set_iommu(&pci_bus_type, &arm_smmu_ops);
+	if (!registered) {
+		ret = platform_driver_register(&arm_smmu_driver);
+		registered = !ret;
+	}
+	return ret;
 }
 
 static void __exit arm_smmu_exit(void)
@@ -2716,6 +2660,20 @@ static void __exit arm_smmu_exit(void)
 subsys_initcall(arm_smmu_init);
 module_exit(arm_smmu_exit);
 
+static int __init arm_smmu_of_init(struct device_node *np)
+{
+	int ret = arm_smmu_init();
+
+	if (ret)
+		return ret;
+
+	if (!of_platform_device_create(np, NULL, platform_bus_type.dev_root))
+		return -ENODEV;
+
+	return 0;
+}
+IOMMU_OF_DECLARE(arm_smmuv3, "arm,smmu-v3", arm_smmu_of_init);
+
 MODULE_DESCRIPTION("IOMMU API for ARM architected SMMUv3 implementations");
 MODULE_AUTHOR("Will Deacon <will.deacon@arm.com>");
 MODULE_LICENSE("GPL v2");