Re: [PATCH 6/6] iommu/arm-smmu: Make use of phandle iterators in device-tree parsing

2016-03-22 Thread Robin Murphy 

Hi Joerg,

On 22/03/16 17:58, Joerg Roedel wrote:

From: Joerg Roedel 

Remove the usage of of_parse_phandle_with_args() and replace
it by the phandle-iterator implementation so that we can
parse out all of the potentially present 128 stream-ids.


In a stream-matching implementation, a device may quite legitimately own 
anything up to _all_ of the stream IDs (32768, or 65536 if we ever 
implement support for the SMMUv2 EXID extension), so this is only a 
genuine limit for stream indexing (and if anyone ever actually made one 
of those, I don't think they're running mainline on it).


Alternatively, how straightforward is it to change the DT on your 
machine? I'll be getting a v2 of [1] out in a couple of weeks (after 
imminent holidays), which already gets rid of MAX_MASTER_STREAMIDS 
altogether, and might also have grown proper SMR support by then.


Robin.

[1]:http://thread.gmane.org/gmane.linux.kernel.iommu/12454


Signed-off-by: Joerg Roedel 
---
  drivers/iommu/arm-smmu.c | 28 ++--
  1 file changed, 22 insertions(+), 6 deletions(-)

diff --git a/drivers/iommu/arm-smmu.c b/drivers/iommu/arm-smmu.c
index 59ee4b8..413bd64 100644
--- a/drivers/iommu/arm-smmu.c
+++ b/drivers/iommu/arm-smmu.c
@@ -48,7 +48,7 @@
  #include "io-pgtable.h"

  /* Maximum number of stream IDs assigned to a single device */
-#define MAX_MASTER_STREAMIDS   MAX_PHANDLE_ARGS
+#define MAX_MASTER_STREAMIDS   128

  /* Maximum number of context banks per SMMU */
  #define ARM_SMMU_MAX_CBS  128
@@ -349,6 +349,12 @@ struct arm_smmu_domain {
struct iommu_domain domain;
  };

+struct arm_smmu_phandle_args {
+   struct device_node *np;
+   int args_count;
+   uint32_t args[MAX_MASTER_STREAMIDS];
+};
+
  static struct iommu_ops arm_smmu_ops;

  static DEFINE_SPINLOCK(arm_smmu_devices_lock);
@@ -458,7 +464,7 @@ static int insert_smmu_master(struct arm_smmu_device *smmu,

  static int register_smmu_master(struct arm_smmu_device *smmu,
struct device *dev,
-   struct of_phandle_args *masterspec)
+   struct arm_smmu_phandle_args *masterspec)
  {
int i;
struct arm_smmu_master *master;
@@ -1716,7 +1722,8 @@ static int arm_smmu_device_dt_probe(struct 
platform_device *pdev)
struct arm_smmu_device *smmu;
struct device *dev = >dev;
struct rb_node *node;
-   struct of_phandle_args masterspec;
+   struct of_phandle_iterator it;
+   struct arm_smmu_phandle_args masterspec;
int num_irqs, i, err;

smmu = devm_kzalloc(dev, sizeof(*smmu), GFP_KERNEL);
@@ -1777,9 +1784,14 @@ static int arm_smmu_device_dt_probe(struct 
platform_device *pdev)

i = 0;
smmu->masters = RB_ROOT;
-   while (!of_parse_phandle_with_args(dev->of_node, "mmu-masters",
-  "#stream-id-cells", i,
-  )) {
+
+   of_for_each_phandle(, err, dev->of_node,
+   "mmu-masters", "#stream-id-cells", 0) {
+   int count = of_phandle_iterator_args(, masterspec.args,
+MAX_MASTER_STREAMIDS);
+   masterspec.np   = of_node_get(it.node);
+   masterspec.args_count   = count;
+
err = register_smmu_master(smmu, dev, );
if (err) {
dev_err(dev, "failed to add master %s\n",
@@ -1789,6 +1801,10 @@ static int arm_smmu_device_dt_probe(struct 
platform_device *pdev)

i++;
}
+
+   if (i == 0)
+   goto out_put_masters;
+
dev_notice(dev, "registered %d master devices\n", i);

parse_driver_options(smmu);



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Re: [PATCH 6/6] iommu/arm-smmu: Make use of phandle iterators in device-tree parsing

2016-03-22 Thread Rob Herring 
On Tue, Mar 22, 2016 at 12:58 PM, Joerg Roedel  wrote:
> From: Joerg Roedel 
>
> Remove the usage of of_parse_phandle_with_args() and replace
> it by the phandle-iterator implementation so that we can
> parse out all of the potentially present 128 stream-ids.
>
> Signed-off-by: Joerg Roedel 
> ---
>  drivers/iommu/arm-smmu.c | 28 ++--
>  1 file changed, 22 insertions(+), 6 deletions(-)
>
> diff --git a/drivers/iommu/arm-smmu.c b/drivers/iommu/arm-smmu.c
> index 59ee4b8..413bd64 100644
> --- a/drivers/iommu/arm-smmu.c
> +++ b/drivers/iommu/arm-smmu.c
> @@ -48,7 +48,7 @@
>  #include "io-pgtable.h"
>
>  /* Maximum number of stream IDs assigned to a single device */
> -#define MAX_MASTER_STREAMIDS   MAX_PHANDLE_ARGS
> +#define MAX_MASTER_STREAMIDS   128
>
>  /* Maximum number of context banks per SMMU */
>  #define ARM_SMMU_MAX_CBS   128
> @@ -349,6 +349,12 @@ struct arm_smmu_domain {
> struct iommu_domain domain;
>  };
>
> +struct arm_smmu_phandle_args {
> +   struct device_node *np;
> +   int args_count;
> +   uint32_t args[MAX_MASTER_STREAMIDS];
> +};
> +
>  static struct iommu_ops arm_smmu_ops;
>
>  static DEFINE_SPINLOCK(arm_smmu_devices_lock);
> @@ -458,7 +464,7 @@ static int insert_smmu_master(struct arm_smmu_device 
> *smmu,
>
>  static int register_smmu_master(struct arm_smmu_device *smmu,
> struct device *dev,
> -   struct of_phandle_args *masterspec)
> +   struct arm_smmu_phandle_args *masterspec)
>  {
> int i;
> struct arm_smmu_master *master;
> @@ -1716,7 +1722,8 @@ static int arm_smmu_device_dt_probe(struct 
> platform_device *pdev)
> struct arm_smmu_device *smmu;
> struct device *dev = >dev;
> struct rb_node *node;
> -   struct of_phandle_args masterspec;
> +   struct of_phandle_iterator it;
> +   struct arm_smmu_phandle_args masterspec;

Isn't this a bit big to put on the stack being ~512 bytes?

> int num_irqs, i, err;
>
> smmu = devm_kzalloc(dev, sizeof(*smmu), GFP_KERNEL);
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[PATCH 6/6] iommu/arm-smmu: Make use of phandle iterators in device-tree parsing

2016-03-22 Thread Joerg Roedel 
From: Joerg Roedel 

Remove the usage of of_parse_phandle_with_args() and replace
it by the phandle-iterator implementation so that we can
parse out all of the potentially present 128 stream-ids.

Signed-off-by: Joerg Roedel 
---
 drivers/iommu/arm-smmu.c | 28 ++--
 1 file changed, 22 insertions(+), 6 deletions(-)

diff --git a/drivers/iommu/arm-smmu.c b/drivers/iommu/arm-smmu.c
index 59ee4b8..413bd64 100644
--- a/drivers/iommu/arm-smmu.c
+++ b/drivers/iommu/arm-smmu.c
@@ -48,7 +48,7 @@
 #include "io-pgtable.h"
 
 /* Maximum number of stream IDs assigned to a single device */
-#define MAX_MASTER_STREAMIDS   MAX_PHANDLE_ARGS
+#define MAX_MASTER_STREAMIDS   128
 
 /* Maximum number of context banks per SMMU */
 #define ARM_SMMU_MAX_CBS   128
@@ -349,6 +349,12 @@ struct arm_smmu_domain {
struct iommu_domain domain;
 };
 
+struct arm_smmu_phandle_args {
+   struct device_node *np;
+   int args_count;
+   uint32_t args[MAX_MASTER_STREAMIDS];
+};
+
 static struct iommu_ops arm_smmu_ops;
 
 static DEFINE_SPINLOCK(arm_smmu_devices_lock);
@@ -458,7 +464,7 @@ static int insert_smmu_master(struct arm_smmu_device *smmu,
 
 static int register_smmu_master(struct arm_smmu_device *smmu,
struct device *dev,
-   struct of_phandle_args *masterspec)
+   struct arm_smmu_phandle_args *masterspec)
 {
int i;
struct arm_smmu_master *master;
@@ -1716,7 +1722,8 @@ static int arm_smmu_device_dt_probe(struct 
platform_device *pdev)
struct arm_smmu_device *smmu;
struct device *dev = >dev;
struct rb_node *node;
-   struct of_phandle_args masterspec;
+   struct of_phandle_iterator it;
+   struct arm_smmu_phandle_args masterspec;
int num_irqs, i, err;
 
smmu = devm_kzalloc(dev, sizeof(*smmu), GFP_KERNEL);
@@ -1777,9 +1784,14 @@ static int arm_smmu_device_dt_probe(struct 
platform_device *pdev)
 
i = 0;
smmu->masters = RB_ROOT;
-   while (!of_parse_phandle_with_args(dev->of_node, "mmu-masters",
-  "#stream-id-cells", i,
-  )) {
+
+   of_for_each_phandle(, err, dev->of_node,
+   "mmu-masters", "#stream-id-cells", 0) {
+   int count = of_phandle_iterator_args(, masterspec.args,
+MAX_MASTER_STREAMIDS);
+   masterspec.np   = of_node_get(it.node);
+   masterspec.args_count   = count;
+
err = register_smmu_master(smmu, dev, );
if (err) {
dev_err(dev, "failed to add master %s\n",
@@ -1789,6 +1801,10 @@ static int arm_smmu_device_dt_probe(struct 
platform_device *pdev)
 
i++;
}
+
+   if (i == 0)
+   goto out_put_masters;
+
dev_notice(dev, "registered %d master devices\n", i);
 
parse_driver_options(smmu);
-- 
1.9.1

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[PATCH 3/6] of: Remove counting special case from __of_parse_phandle_with_args()

2016-03-22 Thread Joerg Roedel 
From: Joerg Roedel 

The index = -1 case in __of_parse_phandle_with_args() is
used to just return the number of phandles. That special
case needs extra handling, so move it to the place where it
is needed: of_count_phandle_with_args().

This allows to further simplify __of_parse_phandle_with_args()
later on.

Signed-off-by: Joerg Roedel 
---
 drivers/of/base.c | 19 ++-
 1 file changed, 14 insertions(+), 5 deletions(-)

diff --git a/drivers/of/base.c b/drivers/of/base.c
index 4036512..15593cd 100644
--- a/drivers/of/base.c
+++ b/drivers/of/base.c
@@ -1583,10 +1583,7 @@ static int __of_parse_phandle_with_args(const struct 
device_node *np,
 * Unlock node before returning result; will be one of:
 * -ENOENT : index is for empty phandle
 * -EINVAL : parsing error on data
-* [1..n]  : Number of phandle (count mode; when index = -1)
 */
-   if (rc == -ENOENT && index < 0)
-   rc = cur_index;
 
  err:
if (it.node)
@@ -1722,8 +1719,20 @@ EXPORT_SYMBOL(of_parse_phandle_with_fixed_args);
 int of_count_phandle_with_args(const struct device_node *np, const char 
*list_name,
const char *cells_name)
 {
-   return __of_parse_phandle_with_args(np, list_name, cells_name, 0, -1,
-   NULL);
+   struct of_phandle_iterator it;
+   int rc, cur_index = 0;
+
+   rc = of_phandle_iterator_init(, np, list_name, cells_name, 0);
+   if (rc)
+   return rc;
+
+   while ((rc = of_phandle_iterator_next()) == 0)
+   cur_index += 1;
+
+   if (rc != -ENOENT)
+   return rc;
+
+   return cur_index;
 }
 EXPORT_SYMBOL(of_count_phandle_with_args);
 
-- 
1.9.1

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[PATCH 5/6] of: Introduce of_phandle_iterator_args()

2016-03-22 Thread Joerg Roedel 
From: Joerg Roedel 

This helper function can be used to copy the arguments of a
phandle to an array.

Signed-off-by: Joerg Roedel 
---
 drivers/of/base.c  | 29 +++--
 include/linux/of.h | 10 ++
 2 files changed, 33 insertions(+), 6 deletions(-)

diff --git a/drivers/of/base.c b/drivers/of/base.c
index 471d3d9..008988b 100644
--- a/drivers/of/base.c
+++ b/drivers/of/base.c
@@ -1533,6 +1533,23 @@ err:
return -EINVAL;
 }
 
+int of_phandle_iterator_args(struct of_phandle_iterator *it,
+uint32_t *args,
+int size)
+{
+   int i, count;
+
+   count = it->cur_count;
+
+   if (WARN_ON(size < count))
+   count = size;
+
+   for (i = 0; i < count; i++)
+   args[i] = be32_to_cpup(it->cur++);
+
+   return count;
+}
+
 static int __of_parse_phandle_with_args(const struct device_node *np,
const char *list_name,
const char *cells_name,
@@ -1556,13 +1573,13 @@ static int __of_parse_phandle_with_args(const struct 
device_node *np,
goto err;
 
if (out_args) {
-   int i;
-   if (WARN_ON(it.cur_count > MAX_PHANDLE_ARGS))
-   it.cur_count = MAX_PHANDLE_ARGS;
+   int c;
+
+   c = of_phandle_iterator_args(,
+out_args->args,
+MAX_PHANDLE_ARGS);
out_args->np = it.node;
-   out_args->args_count = it.cur_count;
-   for (i = 0; i < it.cur_count; i++)
-   out_args->args[i] = 
be32_to_cpup(it.cur++);
+   out_args->args_count = c;
} else {
of_node_put(it.node);
}
diff --git a/include/linux/of.h b/include/linux/of.h
index 05e38ed..c91f8b1 100644
--- a/include/linux/of.h
+++ b/include/linux/of.h
@@ -359,6 +359,9 @@ extern int of_phandle_iterator_init(struct 
of_phandle_iterator *it,
int cell_count);
 
 extern int of_phandle_iterator_next(struct of_phandle_iterator *it);
+extern int of_phandle_iterator_args(struct of_phandle_iterator *it,
+   uint32_t *args,
+   int size);
 
 extern void of_alias_scan(void * (*dt_alloc)(u64 size, u64 align));
 extern int of_alias_get_id(struct device_node *np, const char *stem);
@@ -648,6 +651,13 @@ static inline int of_phandle_iterator_next(struct 
of_phandle_iterator *it)
return -ENOSYS;
 }
 
+static inline int of_phandle_iterator_args(struct of_phandle_iterator *it,
+  uint32_t *args,
+  int size)
+{
+   return 0;
+}
+
 static inline int of_alias_get_id(struct device_node *np, const char *stem)
 {
return -ENOSYS;
-- 
1.9.1

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[PATCH 2/6] of: Move phandle walking to of_phandle_iterator_next()

2016-03-22 Thread Joerg Roedel 
From: Joerg Roedel 

Move the code to walk over the phandles out of the loop in
__of_parse_phandle_with_args() to a separate function that
just works with the iterator handle: of_phandle_iterator_next().

Signed-off-by: Joerg Roedel 
---
 drivers/of/base.c  | 130 ++---
 include/linux/of.h |   7 +++
 2 files changed, 81 insertions(+), 56 deletions(-)

diff --git a/drivers/of/base.c b/drivers/of/base.c
index bfdb09b..4036512 100644
--- a/drivers/of/base.c
+++ b/drivers/of/base.c
@@ -1464,6 +1464,75 @@ int of_phandle_iterator_init(struct of_phandle_iterator 
*it,
return 0;
 }
 
+int of_phandle_iterator_next(struct of_phandle_iterator *it)
+{
+   uint32_t count = 0;
+
+   if (it->node) {
+   of_node_put(it->node);
+   it->node = NULL;
+   }
+
+   if (!it->cur || it->phandle_end >= it->list_end)
+   return -ENOENT;
+
+   it->cur = it->phandle_end;
+
+   /* If phandle is 0, then it is an empty entry with no arguments. */
+   it->phandle = be32_to_cpup(it->cur++);
+
+   if (it->phandle) {
+
+   /*
+* Find the provider node and parse the #*-cells property to
+* determine the argument length.
+*/
+   it->node = of_find_node_by_phandle(it->phandle);
+
+   if (it->cells_name) {
+   if (!it->node) {
+   pr_err("%s: could not find phandle\n",
+  it->parent->full_name);
+   goto err;
+   }
+
+   if (of_property_read_u32(it->node, it->cells_name,
+)) {
+   pr_err("%s: could not get %s for %s\n",
+  it->parent->full_name,
+  it->cells_name,
+  it->node->full_name);
+   goto err;
+   }
+   } else {
+   count = it->cell_count;
+   }
+
+   /*
+* Make sure that the arguments actually fit in the remaining
+* property data length
+*/
+   if (it->cur + count > it->list_end) {
+   pr_err("%s: arguments longer than property\n",
+  it->parent->full_name);
+   goto err;
+   }
+   }
+
+   it->phandle_end = it->cur + count;
+   it->cur_count = count;
+
+   return 0;
+
+err:
+   if (it->node) {
+   of_node_put(it->node);
+   it->node = NULL;
+   }
+
+   return -EINVAL;
+}
+
 static int __of_parse_phandle_with_args(const struct device_node *np,
const char *list_name,
const char *cells_name,
@@ -1479,59 +1548,9 @@ static int __of_parse_phandle_with_args(const struct 
device_node *np,
return rc;
 
/* Loop over the phandles until all the requested entry is found */
-   while (it.cur < it.list_end) {
-   rc = -EINVAL;
-   it.cur_count = 0;
-
-   /*
-* If phandle is 0, then it is an empty entry with no
-* arguments.  Skip forward to the next entry.
-*/
-   it.phandle = be32_to_cpup(it.cur++);
-   if (it.phandle) {
-   /*
-* Find the provider node and parse the #*-cells
-* property to determine the argument length.
-*
-* This is not needed if the cell count is hard-coded
-* (i.e. cells_name not set, but cell_count is set),
-* except when we're going to return the found node
-* below.
-*/
-   if (it.cells_name || cur_index == index) {
-   it.node = of_find_node_by_phandle(it.phandle);
-   if (!it.node) {
-   pr_err("%s: could not find phandle\n",
-   it.parent->full_name);
-   goto err;
-   }
-   }
-
-   if (it.cells_name) {
-   if (of_property_read_u32(it.node, it.cells_name,
-_count)) {
-   pr_err("%s: could not get %s for %s\n",
-   it.parent->full_name, 
it.cells_name,
-   it.node->full_name);
-

[PATCH 0/6] of: Implement iterator for phandles

2016-03-22 Thread Joerg Roedel 
Hi,

here is an implementation of the iterator over phandles
concept which Rob Herring suggested to me some time ago. My
approach is a little bit different from what the diff showed
back then, but it gets rid of the allocation and 'struct
'struct of_phandle_args' misuse.

I also converted the arm-smmu driver to make use of the
iterator. The resulting kernel boots on my AMD Seattle
system and fixes the warning triggered there. The patches
now also pass all dt-unittests in my kvm environment.

Please review. Patches are based on v4.5.

Thanks,

Joerg

Changes since RFC post:

* Reordered members of 'struct of_phandle_iterator' and did
  some renaming

* Removed index counting from the iterator

* Split up iterator implementation into multiple patches

* Fixed the code to survive all dt-unittests, tested with each
  patch in this series

* Re-added and updated some comments which got lost during the
  conversion.

* Added of_for_each_phandle macro for easier handling

* Moved the counting special-case from __of_parse_phandle_with_args
  directly to of_count_phandle_with_args for code
  simplification

* Removed some iterator helper functions

* Formatting and style changes

Joerg Roedel (6):
  of: Introduce struct of_phandle_iterator
  of: Move phandle walking to of_phandle_iterator_next()
  of: Remove counting special case from __of_parse_phandle_with_args()
  of: Introduce of_for_each_phandle() helper macro
  of: Introduce of_phandle_iterator_args()
  iommu/arm-smmu: Make use of phandle iterators in device-tree parsing

 drivers/iommu/arm-smmu.c |  28 +--
 drivers/of/base.c| 206 ++-
 include/linux/of.h   |  56 +
 3 files changed, 211 insertions(+), 79 deletions(-)

-- 
1.9.1

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Re: [PATCH] arm64/dma-mapping: Add DMA_ATTR_ALLOC_SINGLE_PAGES support

2016-03-22 Thread Doug Anderson 
Will,

On Mon, Mar 21, 2016 at 11:01 AM, Will Deacon  wrote:
> On Thu, Mar 03, 2016 at 02:54:26AM +0800, Yong Wu wrote:
>> Sometimes it is not worth for the iommu allocating big chunks.
>> Here we enable DMA_ATTR_ALLOC_SINGLE_PAGES which could help avoid to
>> allocate big chunks while iommu allocating buffer.
>>
>> More information about this attribute, please check Doug's commit[1].
>>
>> [1]: https://lkml.org/lkml/2016/1/11/720
>>
>> Cc: Robin Murphy 
>> Suggested-by: Douglas Anderson 
>> Signed-off-by: Yong Wu 
>> ---
>>
>> Our video drivers may soon use this.
>>
>>  arch/arm64/mm/dma-mapping.c |  4 ++--
>>  drivers/iommu/dma-iommu.c   | 14 ++
>>  include/linux/dma-iommu.h   |  4 ++--
>>  3 files changed, 14 insertions(+), 8 deletions(-)
>>
>> diff --git a/arch/arm64/mm/dma-mapping.c b/arch/arm64/mm/dma-mapping.c
>> index 331c4ca..3225e3ca 100644
>> --- a/arch/arm64/mm/dma-mapping.c
>> +++ b/arch/arm64/mm/dma-mapping.c
>> @@ -562,8 +562,8 @@ static void *__iommu_alloc_attrs(struct device *dev, 
>> size_t size,
>>   struct page **pages;
>>   pgprot_t prot = __get_dma_pgprot(attrs, PAGE_KERNEL, coherent);
>>
>> - pages = iommu_dma_alloc(dev, iosize, gfp, ioprot, handle,
>> - flush_page);
>> + pages = iommu_dma_alloc(dev, iosize, gfp, ioprot, attrs,
>> + handle, flush_page);
>>   if (!pages)
>>   return NULL;
>>
>> diff --git a/drivers/iommu/dma-iommu.c b/drivers/iommu/dma-iommu.c
>> index 72d6182..3569cb6 100644
>> --- a/drivers/iommu/dma-iommu.c
>> +++ b/drivers/iommu/dma-iommu.c
>> @@ -190,7 +190,8 @@ static void __iommu_dma_free_pages(struct page **pages, 
>> int count)
>>   kvfree(pages);
>>  }
>>
>> -static struct page **__iommu_dma_alloc_pages(unsigned int count, gfp_t gfp)
>> +static struct page **__iommu_dma_alloc_pages(unsigned int count, gfp_t gfp,
>> +  struct dma_attrs *attrs)
>>  {
>>   struct page **pages;
>>   unsigned int i = 0, array_size = count * sizeof(*pages);
>> @@ -203,6 +204,10 @@ static struct page **__iommu_dma_alloc_pages(unsigned 
>> int count, gfp_t gfp)
>>   if (!pages)
>>   return NULL;
>>
>> + /* Go straight to 4K chunks if caller says it's OK. */
>> + if (dma_get_attr(DMA_ATTR_ALLOC_SINGLE_PAGES, attrs))
>> + order = 0;
>
> I have a slight snag with this, in that you don't consult the IOMMU
> pgsize_bitmap at any point, and assume that it can map pages at the
> same granularity as the CPU. The documentation for
> DMA_ATTR_ALLOC_SINGLE_PAGES seems to be weaker than that.

Interesting.  Is that something that exists in the real world?  ...or
something you think is coming soon?

I'd argue that such a case existed in the real world then probably
we're already broken.  Unless I'm misreading, existing code will
already fall all the way back to order 0 allocations.  ...so while
existing code might could work if it was called on a totally
unfragmented system, it would already break once some fragmentation
was introduced.

I'm not saying that we shouldn't fix the code to handle this, I'm just
saying that Yong Wu's patch doesn't appear to break any code that
wasn't already broken.  That might be reason to land his code first,
then debate the finer points of whether IOMMUs with less granularity
are likely to exist and whether we need to add complexity to the code
to handle them (or just detect this case and return an error).

>From looking at a WIP patch provided to me by Yong Wu, it looks as if
he thinks several more functions need to change to handle this need
for IOMMUs that can't handle small pages.  That seems to be further
evidence that the work should be done in a separate patch.


Doug
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[PATCH] iommu/rockchip: Only log stall errors when attaching

2016-03-22 Thread Tomeu Vizoso 
Move the logging of timeouts when stalling the MMU to
rk_iommu_attach_device, as it's expected that sometimes the MMU won't
get stalled when detaching a device, and it's not a real problem that
would need to be communicated to the user.

Signed-off-by: Tomeu Vizoso 
---
 drivers/iommu/rockchip-iommu.c | 14 ++
 1 file changed, 6 insertions(+), 8 deletions(-)

diff --git a/drivers/iommu/rockchip-iommu.c b/drivers/iommu/rockchip-iommu.c
index 0253ab35c33b..65325b6742e6 100644
--- a/drivers/iommu/rockchip-iommu.c
+++ b/drivers/iommu/rockchip-iommu.c
@@ -346,13 +346,7 @@ static int rk_iommu_enable_stall(struct rk_iommu *iommu)
 
rk_iommu_command(iommu, RK_MMU_CMD_ENABLE_STALL);
 
-   ret = rk_wait_for(rk_iommu_is_stall_active(iommu), 1);
-   if (ret)
-   for (i = 0; i < iommu->num_mmu; i++)
-   dev_err(iommu->dev, "Enable stall request timed out, 
status: %#08x\n",
-   rk_iommu_read(iommu->bases[i], RK_MMU_STATUS));
-
-   return ret;
+   return rk_wait_for(rk_iommu_is_stall_active(iommu), 1);
 }
 
 static int rk_iommu_disable_stall(struct rk_iommu *iommu)
@@ -798,8 +792,12 @@ static int rk_iommu_attach_device(struct iommu_domain 
*domain,
return 0;
 
ret = rk_iommu_enable_stall(iommu);
-   if (ret)
+   if (ret) {
+   for (i = 0; i < iommu->num_mmu; i++)
+   dev_err(iommu->dev, "Enable stall request timed out, 
status: %#08x\n",
+   rk_iommu_read(iommu->bases[i], RK_MMU_STATUS));
return ret;
+   }
 
ret = rk_iommu_force_reset(iommu);
if (ret)
-- 
2.5.0

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RE: [PATCH 0/7] PAMU driver update

2016-03-22 Thread Codrin Constantin Ciubotariu 
Hi,

Anyone has any comments on this patch-set? Please share your thoughts.

Thanks and best regards,
Codrin

> -Original Message-
> From: Codrin Ciubotariu [mailto:codrin.ciubota...@nxp.com]
> Sent: Monday, 07 March, 2016 5:34 PM
> To: iommu@lists.linux-foundation.org
> Cc: scottw...@freescale.com; varun.se...@freescale.com; linuxppc-
> d...@lists.ozlabs.org; Codrin Constantin Ciubotariu
> Subject: [PATCH 0/7] PAMU driver update
> 
> This patchset addresses a few issues found on PAMU IOMMU and small changes to
> enable power management and to support the
> L3 cache controller on some newer boards.
> 
> The series starts with a clean-up patch, followed by two errata fixes: 
> A-007907
> and A-005982. It continues with two fixes for PCIe support. The last two 
> patches
> add support for power management and compatible strings for new L3 controller
> device-tree nodes.
> 
> Codrin Ciubotariu (2):
>   iommu/fsl: Fix most checkpatch warnings and typos
>   iommu/fsl: Work around erratum A-007907
> 
> Varun Sethi (5):
>   iommu/fsl: Enable OMT cache, before invalidating PAACT and SPAACT
> cache
>   iommu/fsl: Factor out PCI specific code
>   iommu/fsl: Enable default DMA window for PCIe devices once detached
> from domain
>   iommu/fsl: PAMU power management support
>   iommu/fsl: Added cache controller compatible strings for SOCs
> 
>  drivers/iommu/fsl_pamu.c| 322 
> 
>  drivers/iommu/fsl_pamu.h|  30 ++--
>  drivers/iommu/fsl_pamu_domain.c | 160 +---
>  drivers/iommu/fsl_pamu_domain.h |   2 +-
>  4 files changed, 381 insertions(+), 133 deletions(-)
> 
> --
> 1.9.3

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[git pull] IOMMU Updates for Linux v4.6

2016-03-22 Thread Joerg Roedel 
Hi Linus,

The following changes since commit b562e44f507e863c6792946e4e1b1449fbbac85d:

  Linux 4.5 (2016-03-13 21:28:54 -0700)

are available in the git repository at:

  git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu.git 
tags/iommu-updates-v4.6

for you to fetch changes up to 70cf769c5ba283483a42c46f3734202b55dd3041:

  Merge branches 'arm/rockchip', 'arm/exynos', 'arm/smmu', 'arm/mediatek', 
'arm/io-pgtable', 'arm/renesas' and 'core' into next (2016-03-21 14:58:47 +0100)



IOMMU Updates for Linux v4.6

This time with:

* Updates for the Exynos IOMMU driver to make use of default
  domains and to add support for the SYSMMU v5

* New Mediatek IOMMU driver

* Support for the ARMv7 short descriptor format in the
  io-pgtable code

* Default domain support for the ARM SMMU

* Couple of other small fixes all over the place


Andrzej Hajda (1):
  iommu/mediatek: Fix handling of of_count_phandle_with_args result

Anup Patel (1):
  of: iommu: Increment DT node refcount in of_iommu_set_ops()

Arnd Bergmann (3):
  iommu/exynos: Pointers are nto physical addresses
  iommu/mediatek: Select ARM_DMA_USE_IOMMU
  iommu/mediatek: Mark PM functions as __maybe_unused

Dan Carpenter (1):
  iommu/mediatek: Check for NULL instead of IS_ERR()

Joerg Roedel (3):
  Merge branch 'for-joerg/io-pgtable' of 
git://git.kernel.org/.../will/linux into arm/io-pgtable
  Merge branch 'for-joerg/arm-smmu/updates' of 
git://git.kernel.org/.../will/linux into arm/smmu
  Merge branches 'arm/rockchip', 'arm/exynos', 'arm/smmu', 'arm/mediatek', 
'arm/io-pgtable', 'arm/renesas' and 'core' into next

Magnus Damm (1):
  iommu/ipmmu-vmsa: Add r8a7795 DT binding

Marek Szyprowski (14):
  iommu/exynos: Rework iommu group initialization
  iommu/exynos: Add support for IOMMU_DOMAIN_DMA domain type
  iommu/exynos: Remove ARM-specific cache flush interface
  iommu/exynos: Simplify master clock operations
  iommu/exynos: Refactor code (no direct register access)
  iommu/exynos: Refactor fault handling code
  iommu/exynos: Refactor init config code
  iommu/exynos: Unify code for fldp cache invalidation
  iommu/exynos: Add support for SYSMMU controller with bogus version reg
  iommu/exynos: Update device tree documentation
  iommu/exynos: Add support for v5 SYSMMU
  iommu/exynos: Add Maintainers entry for Exynos SYSMMU driver
  iommu/exynos: Support multiple attach_device calls
  iommu/exynos: Use proper readl/writel register interface

Robin Murphy (9):
  iommu/io-pgtable: Add ARMv7 short descriptor support
  iommu/io-pgtable: Add helper functions for TLB ops
  iommu/io-pgtable: Avoid redundant TLB syncs
  iommu/io-pgtable: Rationalise quirk handling
  iommu/arm-smmu: Treat all device transactions as unprivileged
  iommu/arm-smmu: Support DMA-API domains
  iommu/arm-smmu: Allow disabling unmatched stream bypass
  iommu/dma: Fix NEED_SG_DMA_LENGTH dependency
  iommu/io-pgtable-armv7s: Fix kmem_cache_alloc() flags

Simon Horman (1):
  iommu/ipmmu-vmsa: Use ARCH_RENESAS

Will Deacon (3):
  MAINTAINERS: update ARM SMMU entry
  iommu/arm-smmu: Don't fail device attach if already attached to a domain
  iommu/arm-smmu: Treat IOMMU_DOMAIN_DMA as bypass for now

Yong Wu (5):
  dt-bindings: iommu: Add binding for mediatek IOMMU
  dt-bindings: mediatek: Add smi dts binding
  memory: mediatek: Add SMI driver
  iommu/mediatek: Add mt8173 IOMMU driver
  dts: mt8173: Add iommu/smi nodes for mt8173

Yoshihiro Shimoda (1):
  iommu: Fix second argument of trace_map() to report correct paddr

ZhengShunQian (1):
  iommu/rockchip: Reconstruct to support multi slaves

 .../devicetree/bindings/iommu/mediatek,iommu.txt   |  68 ++
 .../bindings/iommu/renesas,ipmmu-vmsa.txt  |  15 +-
 .../devicetree/bindings/iommu/samsung,sysmmu.txt   |  22 +-
 .../memory-controllers/mediatek,smi-common.txt |  24 +
 .../memory-controllers/mediatek,smi-larb.txt   |  25 +
 MAINTAINERS|   8 +
 arch/arm64/boot/dts/mediatek/mt8173.dtsi   |  81 ++
 drivers/iommu/Kconfig  |  42 +-
 drivers/iommu/Makefile |   2 +
 drivers/iommu/arm-smmu-v3.c|  50 +-
 drivers/iommu/arm-smmu.c   |  79 +-
 drivers/iommu/exynos-iommu.c   | 608 +--
 drivers/iommu/io-pgtable-arm-v7s.c | 846 +
 drivers/iommu/io-pgtable-arm.c |  34 +-
 drivers/iommu/io-pgtable.c |   5 +-
 drivers/iommu/io-pgtable.h |  53 +-
 drivers/iommu/iommu.c  |   3