[PATCH 0/7] iommu/arm-smmu: misc. driver updates targetting 3.18

[PATCH 0/7] iommu/arm-smmu: misc. driver updates targetting 3.18

[Will Deacon]

Hi all,

This series is a collection of ARM SMMU updates I have in my tree that
I'd like to get merged for 3.18. This has mostly come out of the vSMMU
work (which is still some way off, as proper testing is proving to be
difficult), but Robin has also added minimal support for MMU-401.

There are a couple of other things on my radar (fixing our reporting of
IOMMU_CAP_CACHE_COHERENCY and wiring up iommu_group_get_for_dev), but
they needn't block sending this series out for review.

Feedback welcome,

Will

--->8

Robin Murphy (2):
  iommu/arm-smmu: fix architecture version detection
  iommu/arm-smmu: support MMU-401

Will Deacon (5):
  iommu/arm-smmu: allow translation stage to be forced on the cmdline
  iommu/arm-smmu: add support for multi-master iommu groups
  iommu/arm-smmu: put iommu_domain pointer in dev->archdata.iommu
  iommu/arm-smmu: use page shift instead of page size to avoid division
  iommu/arm-smmu: don't bother truncating the s1 output size to VA_BITS

 .../devicetree/bindings/iommu/arm,smmu.txt         |   1 +
 drivers/iommu/arm-smmu.c                           | 197 ++++++++++++---------
 2 files changed, 115 insertions(+), 83 deletions(-)

-- 
2.1.0

[PATCH 1/7] iommu/arm-smmu: allow translation stage to be forced on the cmdline

[Will Deacon]

When debugging and testing code on an SMMU that supports nested
translation, it can be useful to restrict the driver to a particular
stage of translation.

This patch adds a module parameter to the ARM SMMU driver to allow this
by restricting the ability of the probe() code to detect support for
only the specified stage.

Signed-off-by: Will Deacon <will.deacon@arm.com>
---
 drivers/iommu/arm-smmu.c | 15 +++++++++++++--
 1 file changed, 13 insertions(+), 2 deletions(-)

diff --git a/drivers/iommu/arm-smmu.c b/drivers/iommu/arm-smmu.c
index a83cc2a2a2ca..958ae8194afe 100644
--- a/drivers/iommu/arm-smmu.c
+++ b/drivers/iommu/arm-smmu.c
@@ -326,6 +326,11 @@
 
 #define FSYNR0_WNR			(1 << 4)
 
+static int force_stage;
+module_param_named(force_stage, force_stage, int, S_IRUGO | S_IWUSR);
+MODULE_PARM_DESC(force_stage,
+	"Force SMMU mappings to be installed@a particular stage of translation. A value of '1' or '2' forces the corresponding stage. All other values are ignored (i.e. no stage is forced). Note that selecting a specific stage will disable support for nested translation.");
+
 struct arm_smmu_smr {
 	u8				idx;
 	u16				mask;
@@ -1716,6 +1721,13 @@ static int arm_smmu_device_cfg_probe(struct arm_smmu_device *smmu)
 		return -ENODEV;
 	}
 #endif
+
+	/* Restrict available stages based on module parameter */
+	if (force_stage == 1)
+		id &= ~(ID0_S2TS | ID0_NTS);
+	else if (force_stage == 2)
+		id &= ~(ID0_S1TS | ID0_NTS);
+
 	if (id & ID0_S1TS) {
 		smmu->features |= ARM_SMMU_FEAT_TRANS_S1;
 		dev_notice(smmu->dev, "\tstage 1 translation\n");
@@ -1732,8 +1744,7 @@ static int arm_smmu_device_cfg_probe(struct arm_smmu_device *smmu)
 	}
 
 	if (!(smmu->features &
-		(ARM_SMMU_FEAT_TRANS_S1 | ARM_SMMU_FEAT_TRANS_S2 |
-		 ARM_SMMU_FEAT_TRANS_NESTED))) {
+		(ARM_SMMU_FEAT_TRANS_S1 | ARM_SMMU_FEAT_TRANS_S2))) {
 		dev_err(smmu->dev, "\tno translation support!\n");
 		return -ENODEV;
 	}
-- 
2.1.0

[PATCH 2/7] iommu/arm-smmu: add support for multi-master iommu groups

[Will Deacon]

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 <will.deacon@arm.com>
---
 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);
 }
 
-- 
2.1.0

[PATCH 2/7] iommu/arm-smmu: add support for multi-master iommu groups

[Joerg Roedel]

On Thu, Sep 04, 2014 at 05:50:00PM +0100, Will Deacon wrote:
>  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;

Using iommu_group_get requires the call-sites to do an iommu_group_put
in the end, but I don't see the call-sites updated.


	Joerg

[PATCH 2/7] iommu/arm-smmu: add support for multi-master iommu groups

[Will Deacon]

Hi Joerg,

On Mon, Sep 15, 2014 at 04:22:57PM +0100, Joerg Roedel wrote:
> On Thu, Sep 04, 2014 at 05:50:00PM +0100, Will Deacon wrote:
> >  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;
> 
> Using iommu_group_get requires the call-sites to do an iommu_group_put
> in the end, but I don't see the call-sites updated.

Well spotted, thanks. Given that we have a reference on the group thanks to
iommu_group_alloc, I think it's better just having the put in this helper.

diff below. Unfortunately, I'm at a conference this week and so testing is
going to be difficult. I'll test early next week and try to get you a pull
request later that week for 3.18.

Will

--->8

diff --git a/drivers/iommu/arm-smmu.c b/drivers/iommu/arm-smmu.c
index d2d8cdaf..939242c 100644
--- a/drivers/iommu/arm-smmu.c
+++ b/drivers/iommu/arm-smmu.c
@@ -474,8 +474,15 @@ static struct arm_smmu_master *find_smmu_master(struct arm_smmu_device *smmu,
 static struct arm_smmu_master_cfg *
 find_smmu_master_cfg(struct device *dev)
 {
+       struct arm_smmu_master_cfg *cfg = NULL;
        struct iommu_group *group = iommu_group_get(dev);
-       return group ? iommu_group_get_iommudata(group) : NULL;
+
+       if (group) {
+               cfg = iommu_group_get_iommudata(group);
+               iommu_group_put(group);
+       }
+
+       return cfg;
 }
 

[PATCH 3/7] iommu/arm-smmu: put iommu_domain pointer in dev->archdata.iommu

[Will Deacon]

In preparation for nested translation support, stick a pointer to the
iommu_domain in dev->archdata.iommu. This makes it much easier to grab
hold of the physical group configuration (e.g. cbndx) when dealing with
vSMMU accesses from a guest.

Signed-off-by: Will Deacon <will.deacon@arm.com>
---
 drivers/iommu/arm-smmu.c | 17 ++++++++++++++---
 1 file changed, 14 insertions(+), 3 deletions(-)

diff --git a/drivers/iommu/arm-smmu.c b/drivers/iommu/arm-smmu.c
index ef6623dbba9a..7ab3cc4ffbb3 100644
--- a/drivers/iommu/arm-smmu.c
+++ b/drivers/iommu/arm-smmu.c
@@ -1206,6 +1206,11 @@ static int arm_smmu_attach_dev(struct iommu_domain *domain, struct device *dev)
 		return -ENXIO;
 	}
 
+	if (dev->archdata.iommu) {
+		dev_err(dev, "already attached to IOMMU domain\n");
+		return -EEXIST;
+	}
+
 	/*
 	 * Sanity check the domain. We don't support domains across
 	 * different SMMUs.
@@ -1232,7 +1237,10 @@ static int arm_smmu_attach_dev(struct iommu_domain *domain, struct device *dev)
 	if (!cfg)
 		return -ENODEV;
 
-	return arm_smmu_domain_add_master(smmu_domain, cfg);
+	ret = arm_smmu_domain_add_master(smmu_domain, cfg);
+	if (!ret)
+		dev->archdata.iommu = domain;
+	return ret;
 }
 
 static void arm_smmu_detach_dev(struct iommu_domain *domain, struct device *dev)
@@ -1241,8 +1249,11 @@ static void arm_smmu_detach_dev(struct iommu_domain *domain, struct device *dev)
 	struct arm_smmu_master_cfg *cfg;
 
 	cfg = find_smmu_master_cfg(dev);
-	if (cfg)
-		arm_smmu_domain_remove_master(smmu_domain, cfg);
+	if (!cfg)
+		return;
+
+	dev->archdata.iommu = NULL;
+	arm_smmu_domain_remove_master(smmu_domain, cfg);
 }
 
 static bool arm_smmu_pte_is_contiguous_range(unsigned long addr,
-- 
2.1.0

[PATCH 4/7] iommu/arm-smmu: use page shift instead of page size to avoid division

[Will Deacon]

Arbitrary integer division is not available in all ARM CPUs, so the GCC
may spit out calls to helper functions which are not implemented in
the kernel.

This patch avoids these problems in the SMMU driver by using page shift
instead of page size, so that divisions by the page size (as required
by the vSMMU code) can be expressed as a simple right shift.

Signed-off-by: Will Deacon <will.deacon@arm.com>
---
 drivers/iommu/arm-smmu.c | 10 +++++-----
 1 file changed, 5 insertions(+), 5 deletions(-)

diff --git a/drivers/iommu/arm-smmu.c b/drivers/iommu/arm-smmu.c
index 7ab3cc4ffbb3..ecad700cd4f4 100644
--- a/drivers/iommu/arm-smmu.c
+++ b/drivers/iommu/arm-smmu.c
@@ -59,7 +59,7 @@
 
 /* SMMU global address space */
 #define ARM_SMMU_GR0(smmu)		((smmu)->base)
-#define ARM_SMMU_GR1(smmu)		((smmu)->base + (smmu)->pagesize)
+#define ARM_SMMU_GR1(smmu)		((smmu)->base + (1 << (smmu)->pgshift))
 
 /*
  * SMMU global address space with conditional offset to access secure
@@ -224,7 +224,7 @@
 
 /* Translation context bank */
 #define ARM_SMMU_CB_BASE(smmu)		((smmu)->base + ((smmu)->size >> 1))
-#define ARM_SMMU_CB(smmu, n)		((n) * (smmu)->pagesize)
+#define ARM_SMMU_CB(smmu, n)		((n) * (1 << (smmu)->pgshift))
 
 #define ARM_SMMU_CB_SCTLR		0x0
 #define ARM_SMMU_CB_RESUME		0x8
@@ -354,7 +354,7 @@ struct arm_smmu_device {
 
 	void __iomem			*base;
 	unsigned long			size;
-	unsigned long			pagesize;
+	unsigned long			pgshift;
 
 #define ARM_SMMU_FEAT_COHERENT_WALK	(1 << 0)
 #define ARM_SMMU_FEAT_STREAM_MATCH	(1 << 1)
@@ -1807,12 +1807,12 @@ static int arm_smmu_device_cfg_probe(struct arm_smmu_device *smmu)
 
 	/* ID1 */
 	id = readl_relaxed(gr0_base + ARM_SMMU_GR0_ID1);
-	smmu->pagesize = (id & ID1_PAGESIZE) ? SZ_64K : SZ_4K;
+	smmu->pgshift = (id & ID1_PAGESIZE) ? 16 : 12;
 
 	/* Check for size mismatch of SMMU address space from mapped region */
 	size = 1 <<
 		(((id >> ID1_NUMPAGENDXB_SHIFT) & ID1_NUMPAGENDXB_MASK) + 1);
-	size *= (smmu->pagesize << 1);
+	size *= 2 << smmu->pgshift;
 	if (smmu->size != size)
 		dev_warn(smmu->dev,
 			"SMMU address space size (0x%lx) differs from mapped region size (0x%lx)!\n",
-- 
2.1.0

[PATCH 5/7] iommu/arm-smmu: don't bother truncating the s1 output size to VA_BITS

[Will Deacon]

In order for nested translation to work correctly, we need to ensure
that the maximum output address size from stage-1 is <= the maximum
supported input address size to stage-2. The latter is currently defined
by VA_BITS, since we make use of the CPU page table functions for
allocating out tables and so the driver currently enforces this
restriction by truncating the stage-1 output size during probe.

In reality, this doesn't make a lot of sense; the guest OS is responsible
for managing the stage-1 page tables, so we actually just need to ensure
that the ID registers of the virtual SMMU interface only advertise the
supported stage-2 input size.

This patch fixes the problem by treating the stage-1 and stage-2 input
address sizes separately.

Reported-by: Tirumalesh Chalamarla <tchalamarla@cavium.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
---
 drivers/iommu/arm-smmu.c | 45 ++++++++++++++++++++++-----------------------
 1 file changed, 22 insertions(+), 23 deletions(-)

diff --git a/drivers/iommu/arm-smmu.c b/drivers/iommu/arm-smmu.c
index ecad700cd4f4..2a7e3331b93a 100644
--- a/drivers/iommu/arm-smmu.c
+++ b/drivers/iommu/arm-smmu.c
@@ -24,7 +24,7 @@
  *	- v7/v8 long-descriptor format
  *	- Non-secure access to the SMMU
  *	- 4k and 64k pages, with contiguous pte hints.
- *	- Up to 42-bit addressing (dependent on VA_BITS)
+ *	- Up to 48-bit addressing (dependent on VA_BITS)
  *	- Context fault reporting
  */
 
@@ -375,8 +375,9 @@ struct arm_smmu_device {
 	u32				num_mapping_groups;
 	DECLARE_BITMAP(smr_map, ARM_SMMU_MAX_SMRS);
 
-	unsigned long			input_size;
+	unsigned long			s1_input_size;
 	unsigned long			s1_output_size;
+	unsigned long			s2_input_size;
 	unsigned long			s2_output_size;
 
 	u32				num_global_irqs;
@@ -755,7 +756,7 @@ static void arm_smmu_init_context_bank(struct arm_smmu_domain *smmu_domain)
 			       gr1_base + ARM_SMMU_GR1_CBA2R(cfg->cbndx));
 
 		/* TTBCR2 */
-		switch (smmu->input_size) {
+		switch (smmu->s1_input_size) {
 		case 32:
 			reg = (TTBCR2_ADDR_32 << TTBCR2_SEP_SHIFT);
 			break;
@@ -824,7 +825,7 @@ static void arm_smmu_init_context_bank(struct arm_smmu_domain *smmu_domain)
 			reg = TTBCR_TG0_64K;
 
 		if (!stage1) {
-			reg |= (64 - smmu->s1_output_size) << TTBCR_T0SZ_SHIFT;
+			reg |= (64 - smmu->s2_input_size) << TTBCR_T0SZ_SHIFT;
 
 			switch (smmu->s2_output_size) {
 			case 32:
@@ -847,7 +848,7 @@ static void arm_smmu_init_context_bank(struct arm_smmu_domain *smmu_domain)
 				break;
 			}
 		} else {
-			reg |= (64 - smmu->input_size) << TTBCR_T0SZ_SHIFT;
+			reg |= (64 - smmu->s1_input_size) << TTBCR_T0SZ_SHIFT;
 		}
 	} else {
 		reg = 0;
@@ -1447,9 +1448,11 @@ static int arm_smmu_handle_mapping(struct arm_smmu_domain *smmu_domain,
 
 	if (cfg->cbar == CBAR_TYPE_S2_TRANS) {
 		stage = 2;
+		input_mask = (1ULL << smmu->s2_input_size) - 1;
 		output_mask = (1ULL << smmu->s2_output_size) - 1;
 	} else {
 		stage = 1;
+		input_mask = (1ULL << smmu->s1_input_size) - 1;
 		output_mask = (1ULL << smmu->s1_output_size) - 1;
 	}
 
@@ -1459,7 +1462,6 @@ static int arm_smmu_handle_mapping(struct arm_smmu_domain *smmu_domain,
 	if (size & ~PAGE_MASK)
 		return -EINVAL;
 
-	input_mask = (1ULL << smmu->input_size) - 1;
 	if ((phys_addr_t)iova & ~input_mask)
 		return -ERANGE;
 
@@ -1831,28 +1833,21 @@ static int arm_smmu_device_cfg_probe(struct arm_smmu_device *smmu)
 	/* ID2 */
 	id = readl_relaxed(gr0_base + ARM_SMMU_GR0_ID2);
 	size = arm_smmu_id_size_to_bits((id >> ID2_IAS_SHIFT) & ID2_IAS_MASK);
+	smmu->s1_output_size = min_t(unsigned long, PHYS_MASK_SHIFT, size);
 
-	/*
-	 * Stage-1 output limited by stage-2 input size due to pgd
-	 * allocation (PTRS_PER_PGD).
-	 */
-	if (smmu->features & ARM_SMMU_FEAT_TRANS_NESTED) {
+	/* Stage-2 input size limited due to pgd allocation (PTRS_PER_PGD) */
 #ifdef CONFIG_64BIT
-		smmu->s1_output_size = min_t(unsigned long, VA_BITS, size);
+	smmu->s2_input_size = min_t(unsigned long, VA_BITS, size);
 #else
-		smmu->s1_output_size = min(32UL, size);
+	smmu->s2_input_size = min(32UL, size);
 #endif
-	} else {
-		smmu->s1_output_size = min_t(unsigned long, PHYS_MASK_SHIFT,
-					     size);
-	}
 
 	/* The stage-2 output mask is also applied for bypass */
 	size = arm_smmu_id_size_to_bits((id >> ID2_OAS_SHIFT) & ID2_OAS_MASK);
 	smmu->s2_output_size = min_t(unsigned long, PHYS_MASK_SHIFT, size);
 
 	if (smmu->version == 1) {
-		smmu->input_size = 32;
+		smmu->s1_input_size = 32;
 	} else {
 #ifdef CONFIG_64BIT
 		size = (id >> ID2_UBS_SHIFT) & ID2_UBS_MASK;
@@ -1860,7 +1855,7 @@ static int arm_smmu_device_cfg_probe(struct arm_smmu_device *smmu)
 #else
 		size = 32;
 #endif
-		smmu->input_size = size;
+		smmu->s1_input_size = size;
 
 		if ((PAGE_SIZE == SZ_4K && !(id & ID2_PTFS_4K)) ||
 		    (PAGE_SIZE == SZ_64K && !(id & ID2_PTFS_64K)) ||
@@ -1871,10 +1866,14 @@ static int arm_smmu_device_cfg_probe(struct arm_smmu_device *smmu)
 		}
 	}
 
-	dev_notice(smmu->dev,
-		   "\t%lu-bit VA, %lu-bit IPA, %lu-bit PA\n",
-		   smmu->input_size, smmu->s1_output_size,
-		   smmu->s2_output_size);
+	if (smmu->features & ARM_SMMU_FEAT_TRANS_S1)
+		dev_notice(smmu->dev, "\tStage-1: %lu-bit VA -> %lu-bit IPA\n",
+			   smmu->s1_input_size, smmu->s1_output_size);
+
+	if (smmu->features & ARM_SMMU_FEAT_TRANS_S2)
+		dev_notice(smmu->dev, "\tStage-2: %lu-bit IPA -> %lu-bit PA\n",
+			   smmu->s2_input_size, smmu->s2_output_size);
+
 	return 0;
 }
 
-- 
2.1.0

[PATCH 5/7] iommu/arm-smmu: don't bother truncating the s1 output size to VA_BITS

[Andreas Schwab]

Will Deacon <will.deacon@arm.com> writes:

> diff --git a/drivers/iommu/arm-smmu.c b/drivers/iommu/arm-smmu.c
> index ecad700cd4f4..2a7e3331b93a 100644
> --- a/drivers/iommu/arm-smmu.c
> +++ b/drivers/iommu/arm-smmu.c
> @@ -24,7 +24,7 @@
>   *	- v7/v8 long-descriptor format
>   *	- Non-secure access to the SMMU
>   *	- 4k and 64k pages, with contiguous pte hints.
> - *	- Up to 42-bit addressing (dependent on VA_BITS)
> + *	- Up to 48-bit addressing (dependent on VA_BITS)

Does that mean that the dependency on !ARM_SMMU for ARM64_VA_BITS_48 is
obsolete?

Andreas.

-- 
Andreas Schwab, schwab at linux-m68k.org
GPG Key fingerprint = 58CA 54C7 6D53 942B 1756  01D3 44D5 214B 8276 4ED5
"And now for something completely different."

[PATCH 5/7] iommu/arm-smmu: don't bother truncating the s1 output size to VA_BITS

[Will Deacon]

On Mon, Dec 01, 2014 at 08:39:18PM +0000, Andreas Schwab wrote:
> Will Deacon <will.deacon@arm.com> writes:
> 
> > diff --git a/drivers/iommu/arm-smmu.c b/drivers/iommu/arm-smmu.c
> > index ecad700cd4f4..2a7e3331b93a 100644
> > --- a/drivers/iommu/arm-smmu.c
> > +++ b/drivers/iommu/arm-smmu.c
> > @@ -24,7 +24,7 @@
> >   *	- v7/v8 long-descriptor format
> >   *	- Non-secure access to the SMMU
> >   *	- 4k and 64k pages, with contiguous pte hints.
> > - *	- Up to 42-bit addressing (dependent on VA_BITS)
> > + *	- Up to 48-bit addressing (dependent on VA_BITS)
> 
> Does that mean that the dependency on !ARM_SMMU for ARM64_VA_BITS_48 is
> obsolete?

No, you need my other patch series for that (we don't handle stage-2
properly without it):

  http://lists.infradead.org/pipermail/linux-arm-kernel/2014-November/306786.html

Will

[PATCH 6/7] iommu/arm-smmu: fix architecture version detection

[Will Deacon]

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

The SMMU driver was relying on a quirk of MMU-500 r2px to identify
the correct architecture version. Since this does not apply to other
implementations, make the architecture version for each supported
implementation explicit.

While we're at it, remove the unnecessary #ifdef since the dependencies
for CONFIG_ARM_SMMU already imply CONFIG_OF.

Signed-off-by: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
---
 drivers/iommu/arm-smmu.c | 47 +++++++++++++++++++++++++----------------------
 1 file changed, 25 insertions(+), 22 deletions(-)

diff --git a/drivers/iommu/arm-smmu.c b/drivers/iommu/arm-smmu.c
index 2a7e3331b93a..1f447e7843ed 100644
--- a/drivers/iommu/arm-smmu.c
+++ b/drivers/iommu/arm-smmu.c
@@ -331,6 +331,11 @@ module_param_named(force_stage, force_stage, int, S_IRUGO | S_IWUSR);
 MODULE_PARM_DESC(force_stage,
 	"Force SMMU mappings to be installed at a particular stage of translation. A value of '1' or '2' forces the corresponding stage. All other values are ignored (i.e. no stage is forced). Note that selecting a specific stage will disable support for nested translation.");
 
+enum arm_smmu_arch_version {
+	ARM_SMMU_V1 = 1,
+	ARM_SMMU_V2,
+};
+
 struct arm_smmu_smr {
 	u8				idx;
 	u16				mask;
@@ -365,7 +370,7 @@ struct arm_smmu_device {
 
 #define ARM_SMMU_OPT_SECURE_CFG_ACCESS (1 << 0)
 	u32				options;
-	int				version;
+	enum arm_smmu_arch_version	version;
 
 	u32				num_context_banks;
 	u32				num_s2_context_banks;
@@ -730,7 +735,7 @@ static void arm_smmu_init_context_bank(struct arm_smmu_domain *smmu_domain)
 
 	/* CBAR */
 	reg = cfg->cbar;
-	if (smmu->version == 1)
+	if (smmu->version == ARM_SMMU_V1)
 		reg |= cfg->irptndx << CBAR_IRPTNDX_SHIFT;
 
 	/*
@@ -745,7 +750,7 @@ static void arm_smmu_init_context_bank(struct arm_smmu_domain *smmu_domain)
 	}
 	writel_relaxed(reg, gr1_base + ARM_SMMU_GR1_CBAR(cfg->cbndx));
 
-	if (smmu->version > 1) {
+	if (smmu->version > ARM_SMMU_V1) {
 		/* CBA2R */
 #ifdef CONFIG_64BIT
 		reg = CBA2R_RW64_64BIT;
@@ -818,7 +823,7 @@ static void arm_smmu_init_context_bank(struct arm_smmu_domain *smmu_domain)
 	 * TTBCR
 	 * We use long descriptor, with inner-shareable WBWA tables in TTBR0.
 	 */
-	if (smmu->version > 1) {
+	if (smmu->version > ARM_SMMU_V1) {
 		if (PAGE_SIZE == SZ_4K)
 			reg = TTBCR_TG0_4K;
 		else
@@ -915,7 +920,7 @@ static int arm_smmu_init_domain_context(struct iommu_domain *domain,
 		goto out_unlock;
 
 	cfg->cbndx = ret;
-	if (smmu->version == 1) {
+	if (smmu->version == ARM_SMMU_V1) {
 		cfg->irptndx = atomic_inc_return(&smmu->irptndx);
 		cfg->irptndx %= smmu->num_context_irqs;
 	} else {
@@ -1726,10 +1731,6 @@ static int arm_smmu_device_cfg_probe(struct arm_smmu_device *smmu)
 	u32 id;
 
 	dev_notice(smmu->dev, "probing hardware configuration...\n");
-
-	/* Primecell ID */
-	id = readl_relaxed(gr0_base + ARM_SMMU_GR0_PIDR2);
-	smmu->version = ((id >> PIDR2_ARCH_SHIFT) & PIDR2_ARCH_MASK) + 1;
 	dev_notice(smmu->dev, "SMMUv%d with:\n", smmu->version);
 
 	/* ID0 */
@@ -1846,7 +1847,7 @@ static int arm_smmu_device_cfg_probe(struct arm_smmu_device *smmu)
 	size = arm_smmu_id_size_to_bits((id >> ID2_OAS_SHIFT) & ID2_OAS_MASK);
 	smmu->s2_output_size = min_t(unsigned long, PHYS_MASK_SHIFT, size);
 
-	if (smmu->version == 1) {
+	if (smmu->version == ARM_SMMU_V1) {
 		smmu->s1_input_size = 32;
 	} else {
 #ifdef CONFIG_64BIT
@@ -1877,8 +1878,18 @@ static int arm_smmu_device_cfg_probe(struct arm_smmu_device *smmu)
 	return 0;
 }
 
+static struct of_device_id arm_smmu_of_match[] = {
+	{ .compatible = "arm,smmu-v1", .data = (void *)ARM_SMMU_V1 },
+	{ .compatible = "arm,smmu-v2", .data = (void *)ARM_SMMU_V2 },
+	{ .compatible = "arm,mmu-400", .data = (void *)ARM_SMMU_V1 },
+	{ .compatible = "arm,mmu-500", .data = (void *)ARM_SMMU_V2 },
+	{ },
+};
+MODULE_DEVICE_TABLE(of, arm_smmu_of_match);
+
 static int arm_smmu_device_dt_probe(struct platform_device *pdev)
 {
+	const struct of_device_id *of_id;
 	struct resource *res;
 	struct arm_smmu_device *smmu;
 	struct device *dev = &pdev->dev;
@@ -1893,6 +1904,9 @@ static int arm_smmu_device_dt_probe(struct platform_device *pdev)
 	}
 	smmu->dev = dev;
 
+	of_id = of_match_node(arm_smmu_of_match, dev->of_node);
+	smmu->version = (enum arm_smmu_arch_version)of_id->data;
+
 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 	smmu->base = devm_ioremap_resource(dev, res);
 	if (IS_ERR(smmu->base))
@@ -1957,7 +1971,7 @@ static int arm_smmu_device_dt_probe(struct platform_device *pdev)
 
 	parse_driver_options(smmu);
 
-	if (smmu->version > 1 &&
+	if (smmu->version > ARM_SMMU_V1 &&
 	    smmu->num_context_banks != smmu->num_context_irqs) {
 		dev_err(dev,
 			"found only %d context interrupt(s) but %d required\n",
@@ -2038,17 +2052,6 @@ static int arm_smmu_device_remove(struct platform_device *pdev)
 	return 0;
 }
 
-#ifdef CONFIG_OF
-static struct of_device_id arm_smmu_of_match[] = {
-	{ .compatible = "arm,smmu-v1", },
-	{ .compatible = "arm,smmu-v2", },
-	{ .compatible = "arm,mmu-400", },
-	{ .compatible = "arm,mmu-500", },
-	{ },
-};
-MODULE_DEVICE_TABLE(of, arm_smmu_of_match);
-#endif
-
 static struct platform_driver arm_smmu_driver = {
 	.driver	= {
 		.owner		= THIS_MODULE,
-- 
2.1.0

[PATCH 7/7] iommu/arm-smmu: support MMU-401

[Will Deacon]

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

MMU-401 is similar to MMU-400, but updated with limited ARMv8 support.

Signed-off-by: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
---
 Documentation/devicetree/bindings/iommu/arm,smmu.txt | 1 +
 drivers/iommu/arm-smmu.c                             | 1 +
 2 files changed, 2 insertions(+)

diff --git a/Documentation/devicetree/bindings/iommu/arm,smmu.txt b/Documentation/devicetree/bindings/iommu/arm,smmu.txt
index 2d0f7cd867ea..06760503a819 100644
--- a/Documentation/devicetree/bindings/iommu/arm,smmu.txt
+++ b/Documentation/devicetree/bindings/iommu/arm,smmu.txt
@@ -14,6 +14,7 @@ conditions.
                         "arm,smmu-v1"
                         "arm,smmu-v2"
                         "arm,mmu-400"
+                        "arm,mmu-401"
                         "arm,mmu-500"
 
                   depending on the particular implementation and/or the
diff --git a/drivers/iommu/arm-smmu.c b/drivers/iommu/arm-smmu.c
index 1f447e7843ed..d2d8cdaf4f0b 100644
--- a/drivers/iommu/arm-smmu.c
+++ b/drivers/iommu/arm-smmu.c
@@ -1882,6 +1882,7 @@ static struct of_device_id arm_smmu_of_match[] = {
 	{ .compatible = "arm,smmu-v1", .data = (void *)ARM_SMMU_V1 },
 	{ .compatible = "arm,smmu-v2", .data = (void *)ARM_SMMU_V2 },
 	{ .compatible = "arm,mmu-400", .data = (void *)ARM_SMMU_V1 },
+	{ .compatible = "arm,mmu-401", .data = (void *)ARM_SMMU_V1 },
 	{ .compatible = "arm,mmu-500", .data = (void *)ARM_SMMU_V2 },
 	{ },
 };
-- 
2.1.0