[PATCH v2 00/05] iommu/ipmmu-vmsa: 32-bit ARM update V2

[PATCH v2 00/05] iommu/ipmmu-vmsa: 32-bit ARM update V2

[Magnus Damm]

iommu/ipmmu-vmsa: 32-bit ARM update V2

[PATCH v2 01/05] iommu/ipmmu-vmsa: Use iommu_device_register()/unregister()
[PATCH v2 02/05] iommu/ipmmu-vmsa: Consistent ->of_xlate() handling
[PATCH v2 03/05] iommu/ipmmu-vmsa: Use fwspec on both 32 and 64-bit ARM
[PATCH v2 04/05] iommu/ipmmu-vmsa: Replace local utlb code with fwspec ids
[PATCH v2 05/05] iommu/ipmmu-vmsa: Clean up device tracking

This series updates the IPMMU driver to make use of recent IOMMU framework
changes and also improves code sharing in the driver between the 32-bit and
64-bit dma-mapping architecture glue code.

Suggested-by: Robin Murphy <robin.murphy@arm.com> (Patch 2 and 4)
Signed-off-by: Robin Murphy <robin.murphy@arm.com> (Patch 3 and 5)
Signed-off-by: Magnus Damm <damm+renesas@opensource.se>
---

 Changes since V1:
 - Minor changes to patch 1 and 2 - thanks Robin and Geert!
 - Added patch 5 to include further clean ups

 Developed on top of v4.13-rc1

 drivers/iommu/ipmmu-vmsa.c |  198 ++++++++++----------------------------------
 1 file changed, 49 insertions(+), 149 deletions(-)

[PATCH v2 01/05] iommu/ipmmu-vmsa: Use iommu_device_register()/unregister()

[Magnus Damm]

From: Magnus Damm <damm+renesas-yzvPICuk2ACczHhG9Qg4qA@public.gmane.org>

Extend the driver to make use of iommu_device_register()/unregister()
functions together with iommu_device_set_ops() and iommu_set_fwnode().

These used to be part of the earlier posted 64-bit ARM (r8a7795) series but
it turns out that these days they are required on 32-bit ARM as well.

Signed-off-by: Magnus Damm <damm+renesas-yzvPICuk2ACczHhG9Qg4qA@public.gmane.org>
---

 Changes since V1:
 - Perform iommu_device_set_ops() and iommu_device_set_fwnode() before
   iommu_device_register() - thanks Robin!

 drivers/iommu/ipmmu-vmsa.c |   10 ++++++++++
 1 file changed, 10 insertions(+)

--- 0001/drivers/iommu/ipmmu-vmsa.c
+++ work/drivers/iommu/ipmmu-vmsa.c	2017-07-17 21:01:47.140607110 +0900
@@ -35,6 +35,7 @@
 struct ipmmu_vmsa_device {
 	struct device *dev;
 	void __iomem *base;
+	struct iommu_device iommu;
 	struct list_head list;
 
 	unsigned int num_utlbs;
@@ -1054,6 +1055,13 @@ static int ipmmu_probe(struct platform_d
 
 	ipmmu_device_reset(mmu);
 
+	iommu_device_set_ops(&mmu->iommu, &ipmmu_ops);
+	iommu_device_set_fwnode(&mmu->iommu, &pdev->dev.of_node->fwnode);
+
+	ret = iommu_device_register(&mmu->iommu);
+	if (ret)
+		return ret;
+
 	/*
 	 * We can't create the ARM mapping here as it requires the bus to have
 	 * an IOMMU, which only happens when bus_set_iommu() is called in
@@ -1077,6 +1085,8 @@ static int ipmmu_remove(struct platform_
 	list_del(&mmu->list);
 	spin_unlock(&ipmmu_devices_lock);
 
+	iommu_device_unregister(&mmu->iommu);
+
 #if defined(CONFIG_ARM) && !defined(CONFIG_IOMMU_DMA)
 	arm_iommu_release_mapping(mmu->mapping);
 #endif

Re: [PATCH v2 01/05] iommu/ipmmu-vmsa: Use iommu_device_register()/unregister()

[Joerg Roedel]

On Mon, Jul 17, 2017 at 10:05:10PM +0900, Magnus Damm wrote:
> --- 0001/drivers/iommu/ipmmu-vmsa.c
> +++ work/drivers/iommu/ipmmu-vmsa.c	2017-07-17 21:01:47.140607110 +0900
> @@ -35,6 +35,7 @@
>  struct ipmmu_vmsa_device {
>  	struct device *dev;
>  	void __iomem *base;
> +	struct iommu_device iommu;
>  	struct list_head list;
>  
>  	unsigned int num_utlbs;
> @@ -1054,6 +1055,13 @@ static int ipmmu_probe(struct platform_d
>  
>  	ipmmu_device_reset(mmu);
>  
> +	iommu_device_set_ops(&mmu->iommu, &ipmmu_ops);
> +	iommu_device_set_fwnode(&mmu->iommu, &pdev->dev.of_node->fwnode);
> +
> +	ret = iommu_device_register(&mmu->iommu);
> +	if (ret)
> +		return ret;
> +

Looks good so far, why don't you also add the iommu to sysfs with
iommu_device_sysfs_add()?


	Joerg

[PATCH v2 02/05] iommu/ipmmu-vmsa: Consistent ->of_xlate() handling

[Magnus Damm]

From: Magnus Damm <damm+renesas-yzvPICuk2ACczHhG9Qg4qA@public.gmane.org>

The 32-bit ARM code gets updated to make use of ->of_xlate() and the
code is shared between 64-bit and 32-bit ARM. The of_device_is_available()
check gets dropped since it is included in of_iommu_xlate().

Suggested-by: Robin Murphy <robin.murphy-5wv7dgnIgG8@public.gmane.org>
Signed-off-by: Magnus Damm <damm+renesas-yzvPICuk2ACczHhG9Qg4qA@public.gmane.org>
---

 Changes since V1:
 - Moved "Initialize once" check to ipmmu_of_xlate() - thanks Geert!

 drivers/iommu/ipmmu-vmsa.c |   51 ++++++++++++++------------------------------
 1 file changed, 17 insertions(+), 34 deletions(-)

--- 0002/drivers/iommu/ipmmu-vmsa.c
+++ work/drivers/iommu/ipmmu-vmsa.c	2017-07-17 21:03:38.340607110 +0900
@@ -734,6 +734,16 @@ error:
 	return ret;
 }
 
+static int ipmmu_of_xlate(struct device *dev,
+			  struct of_phandle_args *spec)
+{
+	/* Initialize once - xlate() will call multiple times */
+	if (to_priv(dev))
+		return 0;
+
+	return ipmmu_init_platform_device(dev);
+}
+
 #if defined(CONFIG_ARM) && !defined(CONFIG_IOMMU_DMA)
 
 static struct iommu_domain *ipmmu_domain_alloc(unsigned type)
@@ -750,11 +760,11 @@ static int ipmmu_add_device(struct devic
 	struct iommu_group *group;
 	int ret;
 
-	if (to_priv(dev)) {
-		dev_warn(dev, "IOMMU driver already assigned to device %s\n",
-			 dev_name(dev));
-		return -EINVAL;
-	}
+	/*
+	 * Only let through devices that have been verified in xlate()
+	 */
+	if (!to_priv(dev))
+		return -ENODEV;
 
 	/* Create a device group and add the device to it. */
 	group = iommu_group_alloc();
@@ -773,10 +783,6 @@ static int ipmmu_add_device(struct devic
 		goto error;
 	}
 
-	ret = ipmmu_init_platform_device(dev);
-	if (ret < 0)
-		goto error;
-
 	/*
 	 * Create the ARM mapping, used by the ARM DMA mapping core to allocate
 	 * VAs. This will allocate a corresponding IOMMU domain.
@@ -817,24 +823,13 @@ error:
 	if (!IS_ERR_OR_NULL(group))
 		iommu_group_remove_device(dev);
 
-	kfree(to_priv(dev)->utlbs);
-	kfree(to_priv(dev));
-	set_priv(dev, NULL);
-
 	return ret;
 }
 
 static void ipmmu_remove_device(struct device *dev)
 {
-	struct ipmmu_vmsa_iommu_priv *priv = to_priv(dev);
-
 	arm_iommu_detach_device(dev);
 	iommu_group_remove_device(dev);
-
-	kfree(priv->utlbs);
-	kfree(priv);
-
-	set_priv(dev, NULL);
 }
 
 static const struct iommu_ops ipmmu_ops = {
@@ -849,6 +844,7 @@ static const struct iommu_ops ipmmu_ops
 	.add_device = ipmmu_add_device,
 	.remove_device = ipmmu_remove_device,
 	.pgsize_bitmap = SZ_1G | SZ_2M | SZ_4K,
+	.of_xlate = ipmmu_of_xlate,
 };
 
 #endif /* !CONFIG_ARM && CONFIG_IOMMU_DMA */
@@ -958,19 +954,6 @@ static struct iommu_group *ipmmu_find_gr
 	return group;
 }
 
-static int ipmmu_of_xlate_dma(struct device *dev,
-			      struct of_phandle_args *spec)
-{
-	/* If the IPMMU device is disabled in DT then return error
-	 * to make sure the of_iommu code does not install ops
-	 * even though the iommu device is disabled
-	 */
-	if (!of_device_is_available(spec->np))
-		return -ENODEV;
-
-	return ipmmu_init_platform_device(dev);
-}
-
 static const struct iommu_ops ipmmu_ops = {
 	.domain_alloc = ipmmu_domain_alloc_dma,
 	.domain_free = ipmmu_domain_free_dma,
@@ -984,7 +967,7 @@ static const struct iommu_ops ipmmu_ops
 	.remove_device = ipmmu_remove_device_dma,
 	.device_group = ipmmu_find_group_dma,
 	.pgsize_bitmap = SZ_1G | SZ_2M | SZ_4K,
-	.of_xlate = ipmmu_of_xlate_dma,
+	.of_xlate = ipmmu_of_xlate,
 };
 
 #endif /* CONFIG_IOMMU_DMA */

[PATCH v2 03/05] iommu/ipmmu-vmsa: Use fwspec on both 32 and 64-bit ARM

[Magnus Damm]

From: Robin Murphy <robin.murphy-5wv7dgnIgG8@public.gmane.org>

Consolidate the 32-bit and 64-bit code to make use of fwspec instead
of archdata for the 32-bit ARM case.

This is a simplified version of the fwspec handling code from Robin
posted as [PATCH] iommu/ipmmu-vmsa: Convert to iommu_fwspec

Signed-off-by: Robin Murphy <robin.murphy-5wv7dgnIgG8@public.gmane.org>
Signed-off-by: Magnus Damm <damm+renesas-yzvPICuk2ACczHhG9Qg4qA@public.gmane.org>
---

 Changes since V1:
 - Rebased to apply on top of earlier changes in series

 drivers/iommu/ipmmu-vmsa.c |   21 +++------------------
 1 file changed, 3 insertions(+), 18 deletions(-)

--- 0004/drivers/iommu/ipmmu-vmsa.c
+++ work/drivers/iommu/ipmmu-vmsa.c	2017-07-17 21:04:54.850607110 +0900
@@ -73,22 +73,9 @@ static struct ipmmu_vmsa_domain *to_vmsa
 	return container_of(dom, struct ipmmu_vmsa_domain, io_domain);
 }
 
-
 static struct ipmmu_vmsa_iommu_priv *to_priv(struct device *dev)
 {
-#if defined(CONFIG_ARM)
-	return dev->archdata.iommu;
-#else
-	return dev->iommu_fwspec->iommu_priv;
-#endif
-}
-static void set_priv(struct device *dev, struct ipmmu_vmsa_iommu_priv *p)
-{
-#if defined(CONFIG_ARM)
-	dev->archdata.iommu = p;
-#else
-	dev->iommu_fwspec->iommu_priv = p;
-#endif
+	return dev->iommu_fwspec ? dev->iommu_fwspec->iommu_priv : NULL;
 }
 
 #define TLB_LOOP_TIMEOUT		100	/* 100us */
@@ -726,7 +713,7 @@ static int ipmmu_init_platform_device(st
 	priv->utlbs = utlbs;
 	priv->num_utlbs = num_utlbs;
 	priv->dev = dev;
-	set_priv(dev, priv);
+	dev->iommu_fwspec->iommu_priv = priv;
 	return 0;
 
 error:
@@ -887,14 +874,12 @@ static void ipmmu_domain_free_dma(struct
 
 static int ipmmu_add_device_dma(struct device *dev)
 {
-	struct iommu_fwspec *fwspec = dev->iommu_fwspec;
 	struct iommu_group *group;
 
 	/*
 	 * Only let through devices that have been verified in xlate()
-	 * We may get called with dev->iommu_fwspec set to NULL.
 	 */
-	if (!fwspec || !fwspec->iommu_priv)
+	if (!to_priv(dev))
 		return -ENODEV;
 
 	group = iommu_group_get_for_dev(dev);

[PATCH v2 04/05] iommu/ipmmu-vmsa: Replace local utlb code with fwspec ids

[Magnus Damm]

From: Magnus Damm <damm+renesas@opensource.se>

Now when both 32-bit and 64-bit code inside the driver is using
fwspec it is possible to replace the utlb handling with fwspec ids
that get populated from ->of_xlate().

Suggested-by: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Magnus Damm <damm+renesas@opensource.se>
---

 Changes since V1:
 - Rebased to apply on top of earlier changes in series

 drivers/iommu/ipmmu-vmsa.c |  104 ++++++++------------------------------------
 1 file changed, 19 insertions(+), 85 deletions(-)

--- 0006/drivers/iommu/ipmmu-vmsa.c
+++ work/drivers/iommu/ipmmu-vmsa.c	2017-07-17 21:12:11.650607110 +0900
@@ -19,6 +19,7 @@
 #include <linux/iommu.h>
 #include <linux/module.h>
 #include <linux/of.h>
+#include <linux/of_platform.h>
 #include <linux/platform_device.h>
 #include <linux/sizes.h>
 #include <linux/slab.h>
@@ -59,8 +60,6 @@ struct ipmmu_vmsa_domain {
 
 struct ipmmu_vmsa_iommu_priv {
 	struct ipmmu_vmsa_device *mmu;
-	unsigned int *utlbs;
-	unsigned int num_utlbs;
 	struct device *dev;
 	struct list_head list;
 };
@@ -550,13 +549,14 @@ static int ipmmu_attach_device(struct io
 			       struct device *dev)
 {
 	struct ipmmu_vmsa_iommu_priv *priv = to_priv(dev);
+	struct iommu_fwspec *fwspec = dev->iommu_fwspec;
 	struct ipmmu_vmsa_device *mmu = priv->mmu;
 	struct ipmmu_vmsa_domain *domain = to_vmsa_domain(io_domain);
 	unsigned long flags;
 	unsigned int i;
 	int ret = 0;
 
-	if (!mmu) {
+	if (!priv || !priv->mmu) {
 		dev_err(dev, "Cannot attach to IPMMU\n");
 		return -ENXIO;
 	}
@@ -583,8 +583,8 @@ static int ipmmu_attach_device(struct io
 	if (ret < 0)
 		return ret;
 
-	for (i = 0; i < priv->num_utlbs; ++i)
-		ipmmu_utlb_enable(domain, priv->utlbs[i]);
+	for (i = 0; i < fwspec->num_ids; ++i)
+		ipmmu_utlb_enable(domain, fwspec->ids[i]);
 
 	return 0;
 }
@@ -592,12 +592,12 @@ static int ipmmu_attach_device(struct io
 static void ipmmu_detach_device(struct iommu_domain *io_domain,
 				struct device *dev)
 {
-	struct ipmmu_vmsa_iommu_priv *priv = to_priv(dev);
+	struct iommu_fwspec *fwspec = dev->iommu_fwspec;
 	struct ipmmu_vmsa_domain *domain = to_vmsa_domain(io_domain);
 	unsigned int i;
 
-	for (i = 0; i < priv->num_utlbs; ++i)
-		ipmmu_utlb_disable(domain, priv->utlbs[i]);
+	for (i = 0; i < fwspec->num_ids; ++i)
+		ipmmu_utlb_disable(domain, fwspec->ids[i]);
 
 	/*
 	 * TODO: Optimize by disabling the context when no device is attached.
@@ -633,102 +633,36 @@ static phys_addr_t ipmmu_iova_to_phys(st
 	return domain->iop->iova_to_phys(domain->iop, iova);
 }
 
-static int ipmmu_find_utlbs(struct ipmmu_vmsa_device *mmu, struct device *dev,
-			    unsigned int *utlbs, unsigned int num_utlbs)
-{
-	unsigned int i;
-
-	for (i = 0; i < num_utlbs; ++i) {
-		struct of_phandle_args args;
-		int ret;
-
-		ret = of_parse_phandle_with_args(dev->of_node, "iommus",
-						 "#iommu-cells", i, &args);
-		if (ret < 0)
-			return ret;
-
-		of_node_put(args.np);
-
-		if (args.np != mmu->dev->of_node || args.args_count != 1)
-			return -EINVAL;
-
-		utlbs[i] = args.args[0];
-	}
-
-	return 0;
-}
-
-static int ipmmu_init_platform_device(struct device *dev)
+static int ipmmu_init_platform_device(struct device *dev,
+				      struct of_phandle_args *args)
 {
+	struct platform_device *ipmmu_pdev;
 	struct ipmmu_vmsa_iommu_priv *priv;
-	struct ipmmu_vmsa_device *mmu;
-	unsigned int *utlbs;
-	unsigned int i;
-	int num_utlbs;
-	int ret = -ENODEV;
-
-	/* Find the master corresponding to the device. */
 
-	num_utlbs = of_count_phandle_with_args(dev->of_node, "iommus",
-					       "#iommu-cells");
-	if (num_utlbs < 0)
+	ipmmu_pdev = of_find_device_by_node(args->np);
+	if (!ipmmu_pdev)
 		return -ENODEV;
 
-	utlbs = kcalloc(num_utlbs, sizeof(*utlbs), GFP_KERNEL);
-	if (!utlbs)
-		return -ENOMEM;
-
-	spin_lock(&ipmmu_devices_lock);
-
-	list_for_each_entry(mmu, &ipmmu_devices, list) {
-		ret = ipmmu_find_utlbs(mmu, dev, utlbs, num_utlbs);
-		if (!ret) {
-			/*
-			 * TODO Take a reference to the MMU to protect
-			 * against device removal.
-			 */
-			break;
-		}
-	}
-
-	spin_unlock(&ipmmu_devices_lock);
-
-	if (ret < 0)
-		goto error;
-
-	for (i = 0; i < num_utlbs; ++i) {
-		if (utlbs[i] >= mmu->num_utlbs) {
-			ret = -EINVAL;
-			goto error;
-		}
-	}
-
 	priv = kzalloc(sizeof(*priv), GFP_KERNEL);
-	if (!priv) {
-		ret = -ENOMEM;
-		goto error;
-	}
+	if (!priv)
+		return -ENOMEM;
 
-	priv->mmu = mmu;
-	priv->utlbs = utlbs;
-	priv->num_utlbs = num_utlbs;
+	priv->mmu = platform_get_drvdata(ipmmu_pdev);
 	priv->dev = dev;
 	dev->iommu_fwspec->iommu_priv = priv;
 	return 0;
-
-error:
-	kfree(utlbs);
-	return ret;
 }
 
 static int ipmmu_of_xlate(struct device *dev,
 			  struct of_phandle_args *spec)
 {
+	iommu_fwspec_add_ids(dev, spec->args, 1);
+
 	/* Initialize once - xlate() will call multiple times */
 	if (to_priv(dev))
 		return 0;
 
-	return ipmmu_init_platform_device(dev);
+	return ipmmu_init_platform_device(dev, spec);
 }
 
 #if defined(CONFIG_ARM) && !defined(CONFIG_IOMMU_DMA)

[PATCH v2 05/05] iommu/ipmmu-vmsa: Clean up device tracking

[Magnus Damm]

From: Robin Murphy <robin.murphy@arm.com>

Get rid of now unused device tracking code. Future code should instead
be able to use driver_for_each_device() for this purpose.

This is a simplified version of the following patch from Robin
[PATCH] iommu/ipmmu-vmsa: Clean up group allocation

Signed-off-by: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Magnus Damm <damm+renesas@opensource.se>
---

 Change since V1:
 - New patch

 drivers/iommu/ipmmu-vmsa.c |   12 ------------
 1 file changed, 12 deletions(-)

--- 0008/drivers/iommu/ipmmu-vmsa.c
+++ work/drivers/iommu/ipmmu-vmsa.c	2017-07-17 21:35:26.690607110 +0900
@@ -37,7 +37,6 @@ struct ipmmu_vmsa_device {
 	struct device *dev;
 	void __iomem *base;
 	struct iommu_device iommu;
-	struct list_head list;
 
 	unsigned int num_utlbs;
 	spinlock_t lock;			/* Protects ctx and domains[] */
@@ -64,9 +63,6 @@ struct ipmmu_vmsa_iommu_priv {
 	struct list_head list;
 };
 
-static DEFINE_SPINLOCK(ipmmu_devices_lock);
-static LIST_HEAD(ipmmu_devices);
-
 static struct ipmmu_vmsa_domain *to_vmsa_domain(struct iommu_domain *dom)
 {
 	return container_of(dom, struct ipmmu_vmsa_domain, io_domain);
@@ -970,10 +966,6 @@ static int ipmmu_probe(struct platform_d
 	 * ipmmu_init() after the probe function returns.
 	 */
 
-	spin_lock(&ipmmu_devices_lock);
-	list_add(&mmu->list, &ipmmu_devices);
-	spin_unlock(&ipmmu_devices_lock);
-
 	platform_set_drvdata(pdev, mmu);
 
 	return 0;
@@ -983,10 +975,6 @@ static int ipmmu_remove(struct platform_
 {
 	struct ipmmu_vmsa_device *mmu = platform_get_drvdata(pdev);
 
-	spin_lock(&ipmmu_devices_lock);
-	list_del(&mmu->list);
-	spin_unlock(&ipmmu_devices_lock);
-
 	iommu_device_unregister(&mmu->iommu);
 
 #if defined(CONFIG_ARM) && !defined(CONFIG_IOMMU_DMA)