Re: [PATCH V11 08/11] drivers: acpi: Handle IOMMU lookup failure with deferred probing or error

2017-05-23 Thread Nate Watterson 

Hi Lorenzo,

On 5/23/2017 5:26 AM, Lorenzo Pieralisi wrote:

On Tue, May 23, 2017 at 02:31:17PM +0530, Sricharan R wrote:

Hi Lorenzo,

On 5/23/2017 2:22 PM, Lorenzo Pieralisi wrote:

On Tue, May 23, 2017 at 02:26:10AM -0400, Nate Watterson wrote:

Hi Sricharan,

On 4/10/2017 7:21 AM, Sricharan R wrote:

This is an equivalent to the DT's handling of the iommu master's probe
with deferred probing when the corrsponding iommu is not probed yet.
The lack of a registered IOMMU can be caused by the lack of a driver for
the IOMMU, the IOMMU device probe not having been performed yet, having
been deferred, or having failed.

The first case occurs when the firmware describes the bus master and
IOMMU topology correctly but no device driver exists for the IOMMU yet
or the device driver has not been compiled in. Return NULL, the caller
will configure the device without an IOMMU.

The second and third cases are handled by deferring the probe of the bus
master device which will eventually get reprobed after the IOMMU.

The last case is currently handled by deferring the probe of the bus
master device as well. A mechanism to either configure the bus master
device without an IOMMU or to fail the bus master device probe depending
on whether the IOMMU is optional or mandatory would be a good
enhancement.

Tested-by: Hanjun Guo 
Reviewed-by: Robin Murphy 
[Lorenzo: Added fixes for dma_coherent_mask overflow, acpi_dma_configure
   called multiple times for same device]
Signed-off-by: Lorenzo Pieralisi 
Signed-off-by: Sricharan R 
---
  drivers/acpi/arm64/iort.c  | 33 -
  drivers/acpi/scan.c| 11 ---
  drivers/base/dma-mapping.c |  2 +-
  include/acpi/acpi_bus.h|  2 +-
  include/linux/acpi.h   |  7 +--
  5 files changed, 47 insertions(+), 8 deletions(-)

diff --git a/drivers/acpi/arm64/iort.c b/drivers/acpi/arm64/iort.c
index 3dd9ec3..e323ece 100644
--- a/drivers/acpi/arm64/iort.c
+++ b/drivers/acpi/arm64/iort.c
@@ -543,6 +543,14 @@ static const struct iommu_ops *iort_iommu_xlate(struct 
device *dev,
const struct iommu_ops *ops = NULL;
int ret = -ENODEV;
struct fwnode_handle *iort_fwnode;
+   struct iommu_fwspec *fwspec = dev->iommu_fwspec;
+
+   /*
+* If we already translated the fwspec there
+* is nothing left to do, return the iommu_ops.
+*/
+   if (fwspec && fwspec->ops)
+   return fwspec->ops;


Is this logic strictly required? It breaks masters with multiple SIDs
as only the first SID is actually added to the master's fwspec.


My bad, that's indeed a silly bug I introduced. Please let me know if the
patch below fixes it, we will send it upstream shortly.



oops, i think emails crossed. Please let me know if you are ok to add
this to the other fixes.


No worries, yes I am ok thanks but please give Nate some time to report
back to make sure the diff I sent actually fixes the problem.


The patch you sent fixes the problem. Thanks for the quick turnaround.



Apologies for the breakage.

Lorenzo



Regards,
  Sricharan



--
Qualcomm Datacenter Technologies as an affiliate of Qualcomm Technologies, Inc.
Qualcomm Technologies, Inc. is a member of the Code Aurora Forum, a Linux 
Foundation Collaborative Project.

Re: [PATCH V11 08/11] drivers: acpi: Handle IOMMU lookup failure with deferred probing or error

2017-05-23 Thread Nate Watterson 

Hi Lorenzo,

On 5/23/2017 5:26 AM, Lorenzo Pieralisi wrote:

On Tue, May 23, 2017 at 02:31:17PM +0530, Sricharan R wrote:

Hi Lorenzo,

On 5/23/2017 2:22 PM, Lorenzo Pieralisi wrote:

On Tue, May 23, 2017 at 02:26:10AM -0400, Nate Watterson wrote:

Hi Sricharan,

On 4/10/2017 7:21 AM, Sricharan R wrote:

This is an equivalent to the DT's handling of the iommu master's probe
with deferred probing when the corrsponding iommu is not probed yet.
The lack of a registered IOMMU can be caused by the lack of a driver for
the IOMMU, the IOMMU device probe not having been performed yet, having
been deferred, or having failed.

The first case occurs when the firmware describes the bus master and
IOMMU topology correctly but no device driver exists for the IOMMU yet
or the device driver has not been compiled in. Return NULL, the caller
will configure the device without an IOMMU.

The second and third cases are handled by deferring the probe of the bus
master device which will eventually get reprobed after the IOMMU.

The last case is currently handled by deferring the probe of the bus
master device as well. A mechanism to either configure the bus master
device without an IOMMU or to fail the bus master device probe depending
on whether the IOMMU is optional or mandatory would be a good
enhancement.

Tested-by: Hanjun Guo 
Reviewed-by: Robin Murphy 
[Lorenzo: Added fixes for dma_coherent_mask overflow, acpi_dma_configure
   called multiple times for same device]
Signed-off-by: Lorenzo Pieralisi 
Signed-off-by: Sricharan R 
---
  drivers/acpi/arm64/iort.c  | 33 -
  drivers/acpi/scan.c| 11 ---
  drivers/base/dma-mapping.c |  2 +-
  include/acpi/acpi_bus.h|  2 +-
  include/linux/acpi.h   |  7 +--
  5 files changed, 47 insertions(+), 8 deletions(-)

diff --git a/drivers/acpi/arm64/iort.c b/drivers/acpi/arm64/iort.c
index 3dd9ec3..e323ece 100644
--- a/drivers/acpi/arm64/iort.c
+++ b/drivers/acpi/arm64/iort.c
@@ -543,6 +543,14 @@ static const struct iommu_ops *iort_iommu_xlate(struct 
device *dev,
const struct iommu_ops *ops = NULL;
int ret = -ENODEV;
struct fwnode_handle *iort_fwnode;
+   struct iommu_fwspec *fwspec = dev->iommu_fwspec;
+
+   /*
+* If we already translated the fwspec there
+* is nothing left to do, return the iommu_ops.
+*/
+   if (fwspec && fwspec->ops)
+   return fwspec->ops;


Is this logic strictly required? It breaks masters with multiple SIDs
as only the first SID is actually added to the master's fwspec.


My bad, that's indeed a silly bug I introduced. Please let me know if the
patch below fixes it, we will send it upstream shortly.



oops, i think emails crossed. Please let me know if you are ok to add
this to the other fixes.


No worries, yes I am ok thanks but please give Nate some time to report
back to make sure the diff I sent actually fixes the problem.


The patch you sent fixes the problem. Thanks for the quick turnaround.



Apologies for the breakage.

Lorenzo



Regards,
  Sricharan



--
Qualcomm Datacenter Technologies as an affiliate of Qualcomm Technologies, Inc.
Qualcomm Technologies, Inc. is a member of the Code Aurora Forum, a Linux 
Foundation Collaborative Project.

Re: [PATCH V11 08/11] drivers: acpi: Handle IOMMU lookup failure with deferred probing or error

2017-05-23 Thread Lorenzo Pieralisi 
On Tue, May 23, 2017 at 02:31:17PM +0530, Sricharan R wrote:
> Hi Lorenzo,
> 
> On 5/23/2017 2:22 PM, Lorenzo Pieralisi wrote:
> > On Tue, May 23, 2017 at 02:26:10AM -0400, Nate Watterson wrote:
> >> Hi Sricharan,
> >>
> >> On 4/10/2017 7:21 AM, Sricharan R wrote:
> >>> This is an equivalent to the DT's handling of the iommu master's probe
> >>> with deferred probing when the corrsponding iommu is not probed yet.
> >>> The lack of a registered IOMMU can be caused by the lack of a driver for
> >>> the IOMMU, the IOMMU device probe not having been performed yet, having
> >>> been deferred, or having failed.
> >>>
> >>> The first case occurs when the firmware describes the bus master and
> >>> IOMMU topology correctly but no device driver exists for the IOMMU yet
> >>> or the device driver has not been compiled in. Return NULL, the caller
> >>> will configure the device without an IOMMU.
> >>>
> >>> The second and third cases are handled by deferring the probe of the bus
> >>> master device which will eventually get reprobed after the IOMMU.
> >>>
> >>> The last case is currently handled by deferring the probe of the bus
> >>> master device as well. A mechanism to either configure the bus master
> >>> device without an IOMMU or to fail the bus master device probe depending
> >>> on whether the IOMMU is optional or mandatory would be a good
> >>> enhancement.
> >>>
> >>> Tested-by: Hanjun Guo 
> >>> Reviewed-by: Robin Murphy 
> >>> [Lorenzo: Added fixes for dma_coherent_mask overflow, acpi_dma_configure
> >>>   called multiple times for same device]
> >>> Signed-off-by: Lorenzo Pieralisi 
> >>> Signed-off-by: Sricharan R 
> >>> ---
> >>>  drivers/acpi/arm64/iort.c  | 33 -
> >>>  drivers/acpi/scan.c| 11 ---
> >>>  drivers/base/dma-mapping.c |  2 +-
> >>>  include/acpi/acpi_bus.h|  2 +-
> >>>  include/linux/acpi.h   |  7 +--
> >>>  5 files changed, 47 insertions(+), 8 deletions(-)
> >>>
> >>> diff --git a/drivers/acpi/arm64/iort.c b/drivers/acpi/arm64/iort.c
> >>> index 3dd9ec3..e323ece 100644
> >>> --- a/drivers/acpi/arm64/iort.c
> >>> +++ b/drivers/acpi/arm64/iort.c
> >>> @@ -543,6 +543,14 @@ static const struct iommu_ops 
> >>> *iort_iommu_xlate(struct device *dev,
> >>>   const struct iommu_ops *ops = NULL;
> >>>   int ret = -ENODEV;
> >>>   struct fwnode_handle *iort_fwnode;
> >>> + struct iommu_fwspec *fwspec = dev->iommu_fwspec;
> >>> +
> >>> + /*
> >>> +  * If we already translated the fwspec there
> >>> +  * is nothing left to do, return the iommu_ops.
> >>> +  */
> >>> + if (fwspec && fwspec->ops)
> >>> + return fwspec->ops;
> >>
> >> Is this logic strictly required? It breaks masters with multiple SIDs
> >> as only the first SID is actually added to the master's fwspec.
> > 
> > My bad, that's indeed a silly bug I introduced. Please let me know if the
> > patch below fixes it, we will send it upstream shortly.
> > 
> 
> oops, i think emails crossed. Please let me know if you are ok to add
> this to the other fixes.

No worries, yes I am ok thanks but please give Nate some time to report
back to make sure the diff I sent actually fixes the problem.

Apologies for the breakage.

Lorenzo

> 
> Regards,
>  Sricharan
>

Re: [PATCH V11 08/11] drivers: acpi: Handle IOMMU lookup failure with deferred probing or error

2017-05-23 Thread Lorenzo Pieralisi 
On Tue, May 23, 2017 at 02:31:17PM +0530, Sricharan R wrote:
> Hi Lorenzo,
> 
> On 5/23/2017 2:22 PM, Lorenzo Pieralisi wrote:
> > On Tue, May 23, 2017 at 02:26:10AM -0400, Nate Watterson wrote:
> >> Hi Sricharan,
> >>
> >> On 4/10/2017 7:21 AM, Sricharan R wrote:
> >>> This is an equivalent to the DT's handling of the iommu master's probe
> >>> with deferred probing when the corrsponding iommu is not probed yet.
> >>> The lack of a registered IOMMU can be caused by the lack of a driver for
> >>> the IOMMU, the IOMMU device probe not having been performed yet, having
> >>> been deferred, or having failed.
> >>>
> >>> The first case occurs when the firmware describes the bus master and
> >>> IOMMU topology correctly but no device driver exists for the IOMMU yet
> >>> or the device driver has not been compiled in. Return NULL, the caller
> >>> will configure the device without an IOMMU.
> >>>
> >>> The second and third cases are handled by deferring the probe of the bus
> >>> master device which will eventually get reprobed after the IOMMU.
> >>>
> >>> The last case is currently handled by deferring the probe of the bus
> >>> master device as well. A mechanism to either configure the bus master
> >>> device without an IOMMU or to fail the bus master device probe depending
> >>> on whether the IOMMU is optional or mandatory would be a good
> >>> enhancement.
> >>>
> >>> Tested-by: Hanjun Guo 
> >>> Reviewed-by: Robin Murphy 
> >>> [Lorenzo: Added fixes for dma_coherent_mask overflow, acpi_dma_configure
> >>>   called multiple times for same device]
> >>> Signed-off-by: Lorenzo Pieralisi 
> >>> Signed-off-by: Sricharan R 
> >>> ---
> >>>  drivers/acpi/arm64/iort.c  | 33 -
> >>>  drivers/acpi/scan.c| 11 ---
> >>>  drivers/base/dma-mapping.c |  2 +-
> >>>  include/acpi/acpi_bus.h|  2 +-
> >>>  include/linux/acpi.h   |  7 +--
> >>>  5 files changed, 47 insertions(+), 8 deletions(-)
> >>>
> >>> diff --git a/drivers/acpi/arm64/iort.c b/drivers/acpi/arm64/iort.c
> >>> index 3dd9ec3..e323ece 100644
> >>> --- a/drivers/acpi/arm64/iort.c
> >>> +++ b/drivers/acpi/arm64/iort.c
> >>> @@ -543,6 +543,14 @@ static const struct iommu_ops 
> >>> *iort_iommu_xlate(struct device *dev,
> >>>   const struct iommu_ops *ops = NULL;
> >>>   int ret = -ENODEV;
> >>>   struct fwnode_handle *iort_fwnode;
> >>> + struct iommu_fwspec *fwspec = dev->iommu_fwspec;
> >>> +
> >>> + /*
> >>> +  * If we already translated the fwspec there
> >>> +  * is nothing left to do, return the iommu_ops.
> >>> +  */
> >>> + if (fwspec && fwspec->ops)
> >>> + return fwspec->ops;
> >>
> >> Is this logic strictly required? It breaks masters with multiple SIDs
> >> as only the first SID is actually added to the master's fwspec.
> > 
> > My bad, that's indeed a silly bug I introduced. Please let me know if the
> > patch below fixes it, we will send it upstream shortly.
> > 
> 
> oops, i think emails crossed. Please let me know if you are ok to add
> this to the other fixes.

No worries, yes I am ok thanks but please give Nate some time to report
back to make sure the diff I sent actually fixes the problem.

Apologies for the breakage.

Lorenzo

> 
> Regards,
>  Sricharan
>

Re: [PATCH V11 08/11] drivers: acpi: Handle IOMMU lookup failure with deferred probing or error

2017-05-23 Thread Sricharan R 
Hi Lorenzo,

On 5/23/2017 2:22 PM, Lorenzo Pieralisi wrote:
> On Tue, May 23, 2017 at 02:26:10AM -0400, Nate Watterson wrote:
>> Hi Sricharan,
>>
>> On 4/10/2017 7:21 AM, Sricharan R wrote:
>>> This is an equivalent to the DT's handling of the iommu master's probe
>>> with deferred probing when the corrsponding iommu is not probed yet.
>>> The lack of a registered IOMMU can be caused by the lack of a driver for
>>> the IOMMU, the IOMMU device probe not having been performed yet, having
>>> been deferred, or having failed.
>>>
>>> The first case occurs when the firmware describes the bus master and
>>> IOMMU topology correctly but no device driver exists for the IOMMU yet
>>> or the device driver has not been compiled in. Return NULL, the caller
>>> will configure the device without an IOMMU.
>>>
>>> The second and third cases are handled by deferring the probe of the bus
>>> master device which will eventually get reprobed after the IOMMU.
>>>
>>> The last case is currently handled by deferring the probe of the bus
>>> master device as well. A mechanism to either configure the bus master
>>> device without an IOMMU or to fail the bus master device probe depending
>>> on whether the IOMMU is optional or mandatory would be a good
>>> enhancement.
>>>
>>> Tested-by: Hanjun Guo 
>>> Reviewed-by: Robin Murphy 
>>> [Lorenzo: Added fixes for dma_coherent_mask overflow, acpi_dma_configure
>>>   called multiple times for same device]
>>> Signed-off-by: Lorenzo Pieralisi 
>>> Signed-off-by: Sricharan R 
>>> ---
>>>  drivers/acpi/arm64/iort.c  | 33 -
>>>  drivers/acpi/scan.c| 11 ---
>>>  drivers/base/dma-mapping.c |  2 +-
>>>  include/acpi/acpi_bus.h|  2 +-
>>>  include/linux/acpi.h   |  7 +--
>>>  5 files changed, 47 insertions(+), 8 deletions(-)
>>>
>>> diff --git a/drivers/acpi/arm64/iort.c b/drivers/acpi/arm64/iort.c
>>> index 3dd9ec3..e323ece 100644
>>> --- a/drivers/acpi/arm64/iort.c
>>> +++ b/drivers/acpi/arm64/iort.c
>>> @@ -543,6 +543,14 @@ static const struct iommu_ops *iort_iommu_xlate(struct 
>>> device *dev,
>>> const struct iommu_ops *ops = NULL;
>>> int ret = -ENODEV;
>>> struct fwnode_handle *iort_fwnode;
>>> +   struct iommu_fwspec *fwspec = dev->iommu_fwspec;
>>> +
>>> +   /*
>>> +* If we already translated the fwspec there
>>> +* is nothing left to do, return the iommu_ops.
>>> +*/
>>> +   if (fwspec && fwspec->ops)
>>> +   return fwspec->ops;
>>
>> Is this logic strictly required? It breaks masters with multiple SIDs
>> as only the first SID is actually added to the master's fwspec.
> 
> My bad, that's indeed a silly bug I introduced. Please let me know if the
> patch below fixes it, we will send it upstream shortly.
> 

oops, i think emails crossed. Please let me know if you are ok to add this
to the other fixes.

Regards,
 Sricharan

> Lorenzo
> 
> -- >8 --
> diff --git a/drivers/acpi/arm64/iort.c b/drivers/acpi/arm64/iort.c
> index c5fecf9..e326f2a 100644
> --- a/drivers/acpi/arm64/iort.c
> +++ b/drivers/acpi/arm64/iort.c
> @@ -666,14 +666,6 @@ static const struct iommu_ops *iort_iommu_xlate(struct 
> device *dev,
>   int ret = -ENODEV;
>   struct fwnode_handle *iort_fwnode;
>  
> - /*
> -  * If we already translated the fwspec there
> -  * is nothing left to do, return the iommu_ops.
> -  */
> - ops = iort_fwspec_iommu_ops(dev->iommu_fwspec);
> - if (ops)
> - return ops;
> -
>   if (node) {
>   iort_fwnode = iort_get_fwnode(node);
>   if (!iort_fwnode)
> @@ -735,6 +727,14 @@ const struct iommu_ops *iort_iommu_configure(struct 
> device *dev)
>   u32 streamid = 0;
>   int err;
>  
> + /*
> +  * If we already translated the fwspec there
> +  * is nothing left to do, return the iommu_ops.
> +  */
> + ops = iort_fwspec_iommu_ops(dev->iommu_fwspec);
> + if (ops)
> + return ops;
> +
>   if (dev_is_pci(dev)) {
>   struct pci_bus *bus = to_pci_dev(dev)->bus;
>   u32 rid;
> 
> 

-- 
"QUALCOMM INDIA, on behalf of Qualcomm Innovation Center, Inc. is a member of 
Code Aurora Forum, hosted by The Linux Foundation

Re: [PATCH V11 08/11] drivers: acpi: Handle IOMMU lookup failure with deferred probing or error

2017-05-23 Thread Sricharan R 
Hi Lorenzo,

On 5/23/2017 2:22 PM, Lorenzo Pieralisi wrote:
> On Tue, May 23, 2017 at 02:26:10AM -0400, Nate Watterson wrote:
>> Hi Sricharan,
>>
>> On 4/10/2017 7:21 AM, Sricharan R wrote:
>>> This is an equivalent to the DT's handling of the iommu master's probe
>>> with deferred probing when the corrsponding iommu is not probed yet.
>>> The lack of a registered IOMMU can be caused by the lack of a driver for
>>> the IOMMU, the IOMMU device probe not having been performed yet, having
>>> been deferred, or having failed.
>>>
>>> The first case occurs when the firmware describes the bus master and
>>> IOMMU topology correctly but no device driver exists for the IOMMU yet
>>> or the device driver has not been compiled in. Return NULL, the caller
>>> will configure the device without an IOMMU.
>>>
>>> The second and third cases are handled by deferring the probe of the bus
>>> master device which will eventually get reprobed after the IOMMU.
>>>
>>> The last case is currently handled by deferring the probe of the bus
>>> master device as well. A mechanism to either configure the bus master
>>> device without an IOMMU or to fail the bus master device probe depending
>>> on whether the IOMMU is optional or mandatory would be a good
>>> enhancement.
>>>
>>> Tested-by: Hanjun Guo 
>>> Reviewed-by: Robin Murphy 
>>> [Lorenzo: Added fixes for dma_coherent_mask overflow, acpi_dma_configure
>>>   called multiple times for same device]
>>> Signed-off-by: Lorenzo Pieralisi 
>>> Signed-off-by: Sricharan R 
>>> ---
>>>  drivers/acpi/arm64/iort.c  | 33 -
>>>  drivers/acpi/scan.c| 11 ---
>>>  drivers/base/dma-mapping.c |  2 +-
>>>  include/acpi/acpi_bus.h|  2 +-
>>>  include/linux/acpi.h   |  7 +--
>>>  5 files changed, 47 insertions(+), 8 deletions(-)
>>>
>>> diff --git a/drivers/acpi/arm64/iort.c b/drivers/acpi/arm64/iort.c
>>> index 3dd9ec3..e323ece 100644
>>> --- a/drivers/acpi/arm64/iort.c
>>> +++ b/drivers/acpi/arm64/iort.c
>>> @@ -543,6 +543,14 @@ static const struct iommu_ops *iort_iommu_xlate(struct 
>>> device *dev,
>>> const struct iommu_ops *ops = NULL;
>>> int ret = -ENODEV;
>>> struct fwnode_handle *iort_fwnode;
>>> +   struct iommu_fwspec *fwspec = dev->iommu_fwspec;
>>> +
>>> +   /*
>>> +* If we already translated the fwspec there
>>> +* is nothing left to do, return the iommu_ops.
>>> +*/
>>> +   if (fwspec && fwspec->ops)
>>> +   return fwspec->ops;
>>
>> Is this logic strictly required? It breaks masters with multiple SIDs
>> as only the first SID is actually added to the master's fwspec.
> 
> My bad, that's indeed a silly bug I introduced. Please let me know if the
> patch below fixes it, we will send it upstream shortly.
> 

oops, i think emails crossed. Please let me know if you are ok to add this
to the other fixes.

Regards,
 Sricharan

> Lorenzo
> 
> -- >8 --
> diff --git a/drivers/acpi/arm64/iort.c b/drivers/acpi/arm64/iort.c
> index c5fecf9..e326f2a 100644
> --- a/drivers/acpi/arm64/iort.c
> +++ b/drivers/acpi/arm64/iort.c
> @@ -666,14 +666,6 @@ static const struct iommu_ops *iort_iommu_xlate(struct 
> device *dev,
>   int ret = -ENODEV;
>   struct fwnode_handle *iort_fwnode;
>  
> - /*
> -  * If we already translated the fwspec there
> -  * is nothing left to do, return the iommu_ops.
> -  */
> - ops = iort_fwspec_iommu_ops(dev->iommu_fwspec);
> - if (ops)
> - return ops;
> -
>   if (node) {
>   iort_fwnode = iort_get_fwnode(node);
>   if (!iort_fwnode)
> @@ -735,6 +727,14 @@ const struct iommu_ops *iort_iommu_configure(struct 
> device *dev)
>   u32 streamid = 0;
>   int err;
>  
> + /*
> +  * If we already translated the fwspec there
> +  * is nothing left to do, return the iommu_ops.
> +  */
> + ops = iort_fwspec_iommu_ops(dev->iommu_fwspec);
> + if (ops)
> + return ops;
> +
>   if (dev_is_pci(dev)) {
>   struct pci_bus *bus = to_pci_dev(dev)->bus;
>   u32 rid;
> 
> 

-- 
"QUALCOMM INDIA, on behalf of Qualcomm Innovation Center, Inc. is a member of 
Code Aurora Forum, hosted by The Linux Foundation

Re: [PATCH V11 08/11] drivers: acpi: Handle IOMMU lookup failure with deferred probing or error

2017-05-23 Thread Sricharan R 
Hi,

On 5/23/2017 11:56 AM, Nate Watterson wrote:
> Hi Sricharan,
> 
> On 4/10/2017 7:21 AM, Sricharan R wrote:
>> This is an equivalent to the DT's handling of the iommu master's probe
>> with deferred probing when the corrsponding iommu is not probed yet.
>> The lack of a registered IOMMU can be caused by the lack of a driver for
>> the IOMMU, the IOMMU device probe not having been performed yet, having
>> been deferred, or having failed.
>>
>> The first case occurs when the firmware describes the bus master and
>> IOMMU topology correctly but no device driver exists for the IOMMU yet
>> or the device driver has not been compiled in. Return NULL, the caller
>> will configure the device without an IOMMU.
>>
>> The second and third cases are handled by deferring the probe of the bus
>> master device which will eventually get reprobed after the IOMMU.
>>
>> The last case is currently handled by deferring the probe of the bus
>> master device as well. A mechanism to either configure the bus master
>> device without an IOMMU or to fail the bus master device probe depending
>> on whether the IOMMU is optional or mandatory would be a good
>> enhancement.
>>
>> Tested-by: Hanjun Guo 
>> Reviewed-by: Robin Murphy 
>> [Lorenzo: Added fixes for dma_coherent_mask overflow, acpi_dma_configure
>>called multiple times for same device]
>> Signed-off-by: Lorenzo Pieralisi 
>> Signed-off-by: Sricharan R 
>> ---
>>   drivers/acpi/arm64/iort.c  | 33 -
>>   drivers/acpi/scan.c| 11 ---
>>   drivers/base/dma-mapping.c |  2 +-
>>   include/acpi/acpi_bus.h|  2 +-
>>   include/linux/acpi.h   |  7 +--
>>   5 files changed, 47 insertions(+), 8 deletions(-)
>>
>> diff --git a/drivers/acpi/arm64/iort.c b/drivers/acpi/arm64/iort.c
>> index 3dd9ec3..e323ece 100644
>> --- a/drivers/acpi/arm64/iort.c
>> +++ b/drivers/acpi/arm64/iort.c
>> @@ -543,6 +543,14 @@ static const struct iommu_ops *iort_iommu_xlate(struct 
>> device *dev,
>>   const struct iommu_ops *ops = NULL;
>>   int ret = -ENODEV;
>>   struct fwnode_handle *iort_fwnode;
>> +struct iommu_fwspec *fwspec = dev->iommu_fwspec;
>> +
>> +/*
>> + * If we already translated the fwspec there
>> + * is nothing left to do, return the iommu_ops.
>> + */
>> +if (fwspec && fwspec->ops)
>> +return fwspec->ops;
> 
> Is this logic strictly required? It breaks masters with multiple SIDs
> as only the first SID is actually added to the master's fwspec.
> 

The logic here is same as what is done in DT, in of_iommu_configure.
This is to pullback the iommu_ops that was set for the device from the
previous run. (when the device probe is deferred and called again).
Infact this piece of hunk was initially missing in ACPI, later added
since a bug was reported [1] on V9 and then this came in as a fix in V10.
But looks like this check should be in iort_iommu_configure.
Lorenzo, is that correct ?


[1] https://www.spinics.net/lists/arm-kernel/msg572069.html

If yes i will add this in the fixes that i have already posted.

Regards,
 Sricharan


>> if (node) {
>>   iort_fwnode = iort_get_fwnode(node);
>> @@ -550,8 +558,17 @@ static const struct iommu_ops *iort_iommu_xlate(struct 
>> device *dev,
>>   return NULL;
>> ops = iommu_ops_from_fwnode(iort_fwnode);
>> +/*
>> + * If the ops look-up fails, this means that either
>> + * the SMMU drivers have not been probed yet or that
>> + * the SMMU drivers are not built in the kernel;
>> + * Depending on whether the SMMU drivers are built-in
>> + * in the kernel or not, defer the IOMMU configuration
>> + * or just abort it.
>> + */
>>   if (!ops)
>> -return NULL;
>> +return iort_iommu_driver_enabled(node->type) ?
>> +   ERR_PTR(-EPROBE_DEFER) : NULL;
>> ret = arm_smmu_iort_xlate(dev, streamid, iort_fwnode, ops);
>>   }
>> @@ -625,12 +642,26 @@ const struct iommu_ops *iort_iommu_configure(struct 
>> device *dev)
>> while (parent) {
>>   ops = iort_iommu_xlate(dev, parent, streamid);
>> +if (IS_ERR_OR_NULL(ops))
>> +return ops;
>> parent = iort_node_get_id(node, ,
>> IORT_IOMMU_TYPE, i++);
>>   }
>>   }
>>   +/*
>> + * If we have reason to believe the IOMMU driver missed the initial
>> + * add_device callback for dev, replay it to get things in order.
>> + */
>> +if (!IS_ERR_OR_NULL(ops) && ops->add_device &&
>> +dev->bus && !dev->iommu_group) {
>> +int err = ops->add_device(dev);
>> +
>> +if (err)
>> +ops = ERR_PTR(err);
>> +}
>> +
>>   return ops;
>>   }
>>   diff --git a/drivers/acpi/scan.c b/drivers/acpi/scan.c
>>

Re: [PATCH V11 08/11] drivers: acpi: Handle IOMMU lookup failure with deferred probing or error

2017-05-23 Thread Sricharan R 
Hi,

On 5/23/2017 11:56 AM, Nate Watterson wrote:
> Hi Sricharan,
> 
> On 4/10/2017 7:21 AM, Sricharan R wrote:
>> This is an equivalent to the DT's handling of the iommu master's probe
>> with deferred probing when the corrsponding iommu is not probed yet.
>> The lack of a registered IOMMU can be caused by the lack of a driver for
>> the IOMMU, the IOMMU device probe not having been performed yet, having
>> been deferred, or having failed.
>>
>> The first case occurs when the firmware describes the bus master and
>> IOMMU topology correctly but no device driver exists for the IOMMU yet
>> or the device driver has not been compiled in. Return NULL, the caller
>> will configure the device without an IOMMU.
>>
>> The second and third cases are handled by deferring the probe of the bus
>> master device which will eventually get reprobed after the IOMMU.
>>
>> The last case is currently handled by deferring the probe of the bus
>> master device as well. A mechanism to either configure the bus master
>> device without an IOMMU or to fail the bus master device probe depending
>> on whether the IOMMU is optional or mandatory would be a good
>> enhancement.
>>
>> Tested-by: Hanjun Guo 
>> Reviewed-by: Robin Murphy 
>> [Lorenzo: Added fixes for dma_coherent_mask overflow, acpi_dma_configure
>>called multiple times for same device]
>> Signed-off-by: Lorenzo Pieralisi 
>> Signed-off-by: Sricharan R 
>> ---
>>   drivers/acpi/arm64/iort.c  | 33 -
>>   drivers/acpi/scan.c| 11 ---
>>   drivers/base/dma-mapping.c |  2 +-
>>   include/acpi/acpi_bus.h|  2 +-
>>   include/linux/acpi.h   |  7 +--
>>   5 files changed, 47 insertions(+), 8 deletions(-)
>>
>> diff --git a/drivers/acpi/arm64/iort.c b/drivers/acpi/arm64/iort.c
>> index 3dd9ec3..e323ece 100644
>> --- a/drivers/acpi/arm64/iort.c
>> +++ b/drivers/acpi/arm64/iort.c
>> @@ -543,6 +543,14 @@ static const struct iommu_ops *iort_iommu_xlate(struct 
>> device *dev,
>>   const struct iommu_ops *ops = NULL;
>>   int ret = -ENODEV;
>>   struct fwnode_handle *iort_fwnode;
>> +struct iommu_fwspec *fwspec = dev->iommu_fwspec;
>> +
>> +/*
>> + * If we already translated the fwspec there
>> + * is nothing left to do, return the iommu_ops.
>> + */
>> +if (fwspec && fwspec->ops)
>> +return fwspec->ops;
> 
> Is this logic strictly required? It breaks masters with multiple SIDs
> as only the first SID is actually added to the master's fwspec.
> 

The logic here is same as what is done in DT, in of_iommu_configure.
This is to pullback the iommu_ops that was set for the device from the
previous run. (when the device probe is deferred and called again).
Infact this piece of hunk was initially missing in ACPI, later added
since a bug was reported [1] on V9 and then this came in as a fix in V10.
But looks like this check should be in iort_iommu_configure.
Lorenzo, is that correct ?


[1] https://www.spinics.net/lists/arm-kernel/msg572069.html

If yes i will add this in the fixes that i have already posted.

Regards,
 Sricharan


>> if (node) {
>>   iort_fwnode = iort_get_fwnode(node);
>> @@ -550,8 +558,17 @@ static const struct iommu_ops *iort_iommu_xlate(struct 
>> device *dev,
>>   return NULL;
>> ops = iommu_ops_from_fwnode(iort_fwnode);
>> +/*
>> + * If the ops look-up fails, this means that either
>> + * the SMMU drivers have not been probed yet or that
>> + * the SMMU drivers are not built in the kernel;
>> + * Depending on whether the SMMU drivers are built-in
>> + * in the kernel or not, defer the IOMMU configuration
>> + * or just abort it.
>> + */
>>   if (!ops)
>> -return NULL;
>> +return iort_iommu_driver_enabled(node->type) ?
>> +   ERR_PTR(-EPROBE_DEFER) : NULL;
>> ret = arm_smmu_iort_xlate(dev, streamid, iort_fwnode, ops);
>>   }
>> @@ -625,12 +642,26 @@ const struct iommu_ops *iort_iommu_configure(struct 
>> device *dev)
>> while (parent) {
>>   ops = iort_iommu_xlate(dev, parent, streamid);
>> +if (IS_ERR_OR_NULL(ops))
>> +return ops;
>> parent = iort_node_get_id(node, ,
>> IORT_IOMMU_TYPE, i++);
>>   }
>>   }
>>   +/*
>> + * If we have reason to believe the IOMMU driver missed the initial
>> + * add_device callback for dev, replay it to get things in order.
>> + */
>> +if (!IS_ERR_OR_NULL(ops) && ops->add_device &&
>> +dev->bus && !dev->iommu_group) {
>> +int err = ops->add_device(dev);
>> +
>> +if (err)
>> +ops = ERR_PTR(err);
>> +}
>> +
>>   return ops;
>>   }
>>   diff --git a/drivers/acpi/scan.c b/drivers/acpi/scan.c
>> index 1926918..2a513cc 100644
>> --- a/drivers/acpi/scan.c
>> +++ b/drivers/acpi/scan.c
>> @@ -1373,20

Re: [PATCH V11 08/11] drivers: acpi: Handle IOMMU lookup failure with deferred probing or error

2017-05-23 Thread Lorenzo Pieralisi 
On Tue, May 23, 2017 at 02:26:10AM -0400, Nate Watterson wrote:
> Hi Sricharan,
> 
> On 4/10/2017 7:21 AM, Sricharan R wrote:
> >This is an equivalent to the DT's handling of the iommu master's probe
> >with deferred probing when the corrsponding iommu is not probed yet.
> >The lack of a registered IOMMU can be caused by the lack of a driver for
> >the IOMMU, the IOMMU device probe not having been performed yet, having
> >been deferred, or having failed.
> >
> >The first case occurs when the firmware describes the bus master and
> >IOMMU topology correctly but no device driver exists for the IOMMU yet
> >or the device driver has not been compiled in. Return NULL, the caller
> >will configure the device without an IOMMU.
> >
> >The second and third cases are handled by deferring the probe of the bus
> >master device which will eventually get reprobed after the IOMMU.
> >
> >The last case is currently handled by deferring the probe of the bus
> >master device as well. A mechanism to either configure the bus master
> >device without an IOMMU or to fail the bus master device probe depending
> >on whether the IOMMU is optional or mandatory would be a good
> >enhancement.
> >
> >Tested-by: Hanjun Guo 
> >Reviewed-by: Robin Murphy 
> >[Lorenzo: Added fixes for dma_coherent_mask overflow, acpi_dma_configure
> >   called multiple times for same device]
> >Signed-off-by: Lorenzo Pieralisi 
> >Signed-off-by: Sricharan R 
> >---
> >  drivers/acpi/arm64/iort.c  | 33 -
> >  drivers/acpi/scan.c| 11 ---
> >  drivers/base/dma-mapping.c |  2 +-
> >  include/acpi/acpi_bus.h|  2 +-
> >  include/linux/acpi.h   |  7 +--
> >  5 files changed, 47 insertions(+), 8 deletions(-)
> >
> >diff --git a/drivers/acpi/arm64/iort.c b/drivers/acpi/arm64/iort.c
> >index 3dd9ec3..e323ece 100644
> >--- a/drivers/acpi/arm64/iort.c
> >+++ b/drivers/acpi/arm64/iort.c
> >@@ -543,6 +543,14 @@ static const struct iommu_ops *iort_iommu_xlate(struct 
> >device *dev,
> > const struct iommu_ops *ops = NULL;
> > int ret = -ENODEV;
> > struct fwnode_handle *iort_fwnode;
> >+struct iommu_fwspec *fwspec = dev->iommu_fwspec;
> >+
> >+/*
> >+ * If we already translated the fwspec there
> >+ * is nothing left to do, return the iommu_ops.
> >+ */
> >+if (fwspec && fwspec->ops)
> >+return fwspec->ops;
> 
> Is this logic strictly required? It breaks masters with multiple SIDs
> as only the first SID is actually added to the master's fwspec.

My bad, that's indeed a silly bug I introduced. Please let me know if the
patch below fixes it, we will send it upstream shortly.

Lorenzo

-- >8 --
diff --git a/drivers/acpi/arm64/iort.c b/drivers/acpi/arm64/iort.c
index c5fecf9..e326f2a 100644
--- a/drivers/acpi/arm64/iort.c
+++ b/drivers/acpi/arm64/iort.c
@@ -666,14 +666,6 @@ static const struct iommu_ops *iort_iommu_xlate(struct 
device *dev,
int ret = -ENODEV;
struct fwnode_handle *iort_fwnode;
 
-   /*
-* If we already translated the fwspec there
-* is nothing left to do, return the iommu_ops.
-*/
-   ops = iort_fwspec_iommu_ops(dev->iommu_fwspec);
-   if (ops)
-   return ops;
-
if (node) {
iort_fwnode = iort_get_fwnode(node);
if (!iort_fwnode)
@@ -735,6 +727,14 @@ const struct iommu_ops *iort_iommu_configure(struct device 
*dev)
u32 streamid = 0;
int err;
 
+   /*
+* If we already translated the fwspec there
+* is nothing left to do, return the iommu_ops.
+*/
+   ops = iort_fwspec_iommu_ops(dev->iommu_fwspec);
+   if (ops)
+   return ops;
+
if (dev_is_pci(dev)) {
struct pci_bus *bus = to_pci_dev(dev)->bus;
u32 rid;

Re: [PATCH V11 08/11] drivers: acpi: Handle IOMMU lookup failure with deferred probing or error

2017-05-23 Thread Lorenzo Pieralisi 
On Tue, May 23, 2017 at 02:26:10AM -0400, Nate Watterson wrote:
> Hi Sricharan,
> 
> On 4/10/2017 7:21 AM, Sricharan R wrote:
> >This is an equivalent to the DT's handling of the iommu master's probe
> >with deferred probing when the corrsponding iommu is not probed yet.
> >The lack of a registered IOMMU can be caused by the lack of a driver for
> >the IOMMU, the IOMMU device probe not having been performed yet, having
> >been deferred, or having failed.
> >
> >The first case occurs when the firmware describes the bus master and
> >IOMMU topology correctly but no device driver exists for the IOMMU yet
> >or the device driver has not been compiled in. Return NULL, the caller
> >will configure the device without an IOMMU.
> >
> >The second and third cases are handled by deferring the probe of the bus
> >master device which will eventually get reprobed after the IOMMU.
> >
> >The last case is currently handled by deferring the probe of the bus
> >master device as well. A mechanism to either configure the bus master
> >device without an IOMMU or to fail the bus master device probe depending
> >on whether the IOMMU is optional or mandatory would be a good
> >enhancement.
> >
> >Tested-by: Hanjun Guo 
> >Reviewed-by: Robin Murphy 
> >[Lorenzo: Added fixes for dma_coherent_mask overflow, acpi_dma_configure
> >   called multiple times for same device]
> >Signed-off-by: Lorenzo Pieralisi 
> >Signed-off-by: Sricharan R 
> >---
> >  drivers/acpi/arm64/iort.c  | 33 -
> >  drivers/acpi/scan.c| 11 ---
> >  drivers/base/dma-mapping.c |  2 +-
> >  include/acpi/acpi_bus.h|  2 +-
> >  include/linux/acpi.h   |  7 +--
> >  5 files changed, 47 insertions(+), 8 deletions(-)
> >
> >diff --git a/drivers/acpi/arm64/iort.c b/drivers/acpi/arm64/iort.c
> >index 3dd9ec3..e323ece 100644
> >--- a/drivers/acpi/arm64/iort.c
> >+++ b/drivers/acpi/arm64/iort.c
> >@@ -543,6 +543,14 @@ static const struct iommu_ops *iort_iommu_xlate(struct 
> >device *dev,
> > const struct iommu_ops *ops = NULL;
> > int ret = -ENODEV;
> > struct fwnode_handle *iort_fwnode;
> >+struct iommu_fwspec *fwspec = dev->iommu_fwspec;
> >+
> >+/*
> >+ * If we already translated the fwspec there
> >+ * is nothing left to do, return the iommu_ops.
> >+ */
> >+if (fwspec && fwspec->ops)
> >+return fwspec->ops;
> 
> Is this logic strictly required? It breaks masters with multiple SIDs
> as only the first SID is actually added to the master's fwspec.

My bad, that's indeed a silly bug I introduced. Please let me know if the
patch below fixes it, we will send it upstream shortly.

Lorenzo

-- >8 --
diff --git a/drivers/acpi/arm64/iort.c b/drivers/acpi/arm64/iort.c
index c5fecf9..e326f2a 100644
--- a/drivers/acpi/arm64/iort.c
+++ b/drivers/acpi/arm64/iort.c
@@ -666,14 +666,6 @@ static const struct iommu_ops *iort_iommu_xlate(struct 
device *dev,
int ret = -ENODEV;
struct fwnode_handle *iort_fwnode;
 
-   /*
-* If we already translated the fwspec there
-* is nothing left to do, return the iommu_ops.
-*/
-   ops = iort_fwspec_iommu_ops(dev->iommu_fwspec);
-   if (ops)
-   return ops;
-
if (node) {
iort_fwnode = iort_get_fwnode(node);
if (!iort_fwnode)
@@ -735,6 +727,14 @@ const struct iommu_ops *iort_iommu_configure(struct device 
*dev)
u32 streamid = 0;
int err;
 
+   /*
+* If we already translated the fwspec there
+* is nothing left to do, return the iommu_ops.
+*/
+   ops = iort_fwspec_iommu_ops(dev->iommu_fwspec);
+   if (ops)
+   return ops;
+
if (dev_is_pci(dev)) {
struct pci_bus *bus = to_pci_dev(dev)->bus;
u32 rid;

Re: [PATCH V11 08/11] drivers: acpi: Handle IOMMU lookup failure with deferred probing or error

2017-05-23 Thread Nate Watterson 

Hi Sricharan,

On 4/10/2017 7:21 AM, Sricharan R wrote:

This is an equivalent to the DT's handling of the iommu master's probe
with deferred probing when the corrsponding iommu is not probed yet.
The lack of a registered IOMMU can be caused by the lack of a driver for
the IOMMU, the IOMMU device probe not having been performed yet, having
been deferred, or having failed.

The first case occurs when the firmware describes the bus master and
IOMMU topology correctly but no device driver exists for the IOMMU yet
or the device driver has not been compiled in. Return NULL, the caller
will configure the device without an IOMMU.

The second and third cases are handled by deferring the probe of the bus
master device which will eventually get reprobed after the IOMMU.

The last case is currently handled by deferring the probe of the bus
master device as well. A mechanism to either configure the bus master
device without an IOMMU or to fail the bus master device probe depending
on whether the IOMMU is optional or mandatory would be a good
enhancement.

Tested-by: Hanjun Guo 
Reviewed-by: Robin Murphy 
[Lorenzo: Added fixes for dma_coherent_mask overflow, acpi_dma_configure
   called multiple times for same device]
Signed-off-by: Lorenzo Pieralisi 
Signed-off-by: Sricharan R 
---
  drivers/acpi/arm64/iort.c  | 33 -
  drivers/acpi/scan.c| 11 ---
  drivers/base/dma-mapping.c |  2 +-
  include/acpi/acpi_bus.h|  2 +-
  include/linux/acpi.h   |  7 +--
  5 files changed, 47 insertions(+), 8 deletions(-)

diff --git a/drivers/acpi/arm64/iort.c b/drivers/acpi/arm64/iort.c
index 3dd9ec3..e323ece 100644
--- a/drivers/acpi/arm64/iort.c
+++ b/drivers/acpi/arm64/iort.c
@@ -543,6 +543,14 @@ static const struct iommu_ops *iort_iommu_xlate(struct 
device *dev,
const struct iommu_ops *ops = NULL;
int ret = -ENODEV;
struct fwnode_handle *iort_fwnode;
+   struct iommu_fwspec *fwspec = dev->iommu_fwspec;
+
+   /*
+* If we already translated the fwspec there
+* is nothing left to do, return the iommu_ops.
+*/
+   if (fwspec && fwspec->ops)
+   return fwspec->ops;


Is this logic strictly required? It breaks masters with multiple SIDs
as only the first SID is actually added to the master's fwspec.

  
  	if (node) {

iort_fwnode = iort_get_fwnode(node);
@@ -550,8 +558,17 @@ static const struct iommu_ops *iort_iommu_xlate(struct 
device *dev,
return NULL;
  
  		ops = iommu_ops_from_fwnode(iort_fwnode);

+   /*
+* If the ops look-up fails, this means that either
+* the SMMU drivers have not been probed yet or that
+* the SMMU drivers are not built in the kernel;
+* Depending on whether the SMMU drivers are built-in
+* in the kernel or not, defer the IOMMU configuration
+* or just abort it.
+*/
if (!ops)
-   return NULL;
+   return iort_iommu_driver_enabled(node->type) ?
+  ERR_PTR(-EPROBE_DEFER) : NULL;
  
  		ret = arm_smmu_iort_xlate(dev, streamid, iort_fwnode, ops);

}
@@ -625,12 +642,26 @@ const struct iommu_ops *iort_iommu_configure(struct 
device *dev)
  
  		while (parent) {

ops = iort_iommu_xlate(dev, parent, streamid);
+   if (IS_ERR_OR_NULL(ops))
+   return ops;
  
  			parent = iort_node_get_id(node, ,

  IORT_IOMMU_TYPE, i++);
}
}
  
+	/*

+* If we have reason to believe the IOMMU driver missed the initial
+* add_device callback for dev, replay it to get things in order.
+*/
+   if (!IS_ERR_OR_NULL(ops) && ops->add_device &&
+   dev->bus && !dev->iommu_group) {
+   int err = ops->add_device(dev);
+
+   if (err)
+   ops = ERR_PTR(err);
+   }
+
return ops;
  }
  
diff --git a/drivers/acpi/scan.c b/drivers/acpi/scan.c

index 1926918..2a513cc 100644
--- a/drivers/acpi/scan.c
+++ b/drivers/acpi/scan.c
@@ -1373,20 +1373,25 @@ enum dev_dma_attr acpi_get_dma_attr(struct acpi_device 
*adev)
   * @dev: The pointer to the device
   * @attr: device dma attributes
   */
-void acpi_dma_configure(struct device *dev, enum dev_dma_attr attr)
+int acpi_dma_configure(struct device *dev, enum dev_dma_attr attr)
  {
const struct iommu_ops *iommu;
+   u64 size;
  
  	iort_set_dma_mask(dev);
  
  	iommu = iort_iommu_configure(dev);

+   if (IS_ERR(iommu))
+   return PTR_ERR(iommu);
  
+	size = max(dev->coherent_dma_mask, dev->coherent_dma_mask + 1);

/*
 * Assume dma valid range starts

Re: [PATCH V11 08/11] drivers: acpi: Handle IOMMU lookup failure with deferred probing or error

2017-05-23 Thread Nate Watterson 

Hi Sricharan,

On 4/10/2017 7:21 AM, Sricharan R wrote:

This is an equivalent to the DT's handling of the iommu master's probe
with deferred probing when the corrsponding iommu is not probed yet.
The lack of a registered IOMMU can be caused by the lack of a driver for
the IOMMU, the IOMMU device probe not having been performed yet, having
been deferred, or having failed.

The first case occurs when the firmware describes the bus master and
IOMMU topology correctly but no device driver exists for the IOMMU yet
or the device driver has not been compiled in. Return NULL, the caller
will configure the device without an IOMMU.

The second and third cases are handled by deferring the probe of the bus
master device which will eventually get reprobed after the IOMMU.

The last case is currently handled by deferring the probe of the bus
master device as well. A mechanism to either configure the bus master
device without an IOMMU or to fail the bus master device probe depending
on whether the IOMMU is optional or mandatory would be a good
enhancement.

Tested-by: Hanjun Guo 
Reviewed-by: Robin Murphy 
[Lorenzo: Added fixes for dma_coherent_mask overflow, acpi_dma_configure
   called multiple times for same device]
Signed-off-by: Lorenzo Pieralisi 
Signed-off-by: Sricharan R 
---
  drivers/acpi/arm64/iort.c  | 33 -
  drivers/acpi/scan.c| 11 ---
  drivers/base/dma-mapping.c |  2 +-
  include/acpi/acpi_bus.h|  2 +-
  include/linux/acpi.h   |  7 +--
  5 files changed, 47 insertions(+), 8 deletions(-)

diff --git a/drivers/acpi/arm64/iort.c b/drivers/acpi/arm64/iort.c
index 3dd9ec3..e323ece 100644
--- a/drivers/acpi/arm64/iort.c
+++ b/drivers/acpi/arm64/iort.c
@@ -543,6 +543,14 @@ static const struct iommu_ops *iort_iommu_xlate(struct 
device *dev,
const struct iommu_ops *ops = NULL;
int ret = -ENODEV;
struct fwnode_handle *iort_fwnode;
+   struct iommu_fwspec *fwspec = dev->iommu_fwspec;
+
+   /*
+* If we already translated the fwspec there
+* is nothing left to do, return the iommu_ops.
+*/
+   if (fwspec && fwspec->ops)
+   return fwspec->ops;


Is this logic strictly required? It breaks masters with multiple SIDs
as only the first SID is actually added to the master's fwspec.

  
  	if (node) {

iort_fwnode = iort_get_fwnode(node);
@@ -550,8 +558,17 @@ static const struct iommu_ops *iort_iommu_xlate(struct 
device *dev,
return NULL;
  
  		ops = iommu_ops_from_fwnode(iort_fwnode);

+   /*
+* If the ops look-up fails, this means that either
+* the SMMU drivers have not been probed yet or that
+* the SMMU drivers are not built in the kernel;
+* Depending on whether the SMMU drivers are built-in
+* in the kernel or not, defer the IOMMU configuration
+* or just abort it.
+*/
if (!ops)
-   return NULL;
+   return iort_iommu_driver_enabled(node->type) ?
+  ERR_PTR(-EPROBE_DEFER) : NULL;
  
  		ret = arm_smmu_iort_xlate(dev, streamid, iort_fwnode, ops);

}
@@ -625,12 +642,26 @@ const struct iommu_ops *iort_iommu_configure(struct 
device *dev)
  
  		while (parent) {

ops = iort_iommu_xlate(dev, parent, streamid);
+   if (IS_ERR_OR_NULL(ops))
+   return ops;
  
  			parent = iort_node_get_id(node, ,

  IORT_IOMMU_TYPE, i++);
}
}
  
+	/*

+* If we have reason to believe the IOMMU driver missed the initial
+* add_device callback for dev, replay it to get things in order.
+*/
+   if (!IS_ERR_OR_NULL(ops) && ops->add_device &&
+   dev->bus && !dev->iommu_group) {
+   int err = ops->add_device(dev);
+
+   if (err)
+   ops = ERR_PTR(err);
+   }
+
return ops;
  }
  
diff --git a/drivers/acpi/scan.c b/drivers/acpi/scan.c

index 1926918..2a513cc 100644
--- a/drivers/acpi/scan.c
+++ b/drivers/acpi/scan.c
@@ -1373,20 +1373,25 @@ enum dev_dma_attr acpi_get_dma_attr(struct acpi_device 
*adev)
   * @dev: The pointer to the device
   * @attr: device dma attributes
   */
-void acpi_dma_configure(struct device *dev, enum dev_dma_attr attr)
+int acpi_dma_configure(struct device *dev, enum dev_dma_attr attr)
  {
const struct iommu_ops *iommu;
+   u64 size;
  
  	iort_set_dma_mask(dev);
  
  	iommu = iort_iommu_configure(dev);

+   if (IS_ERR(iommu))
+   return PTR_ERR(iommu);
  
+	size = max(dev->coherent_dma_mask, dev->coherent_dma_mask + 1);

/*
 * Assume dma valid range starts at 0 and covers the whole
 * coherent_dma_mask.
 */
-   arch_setup_dma_ops(dev,

[PATCH V11 08/11] drivers: acpi: Handle IOMMU lookup failure with deferred probing or error

2017-04-10 Thread Sricharan R 
This is an equivalent to the DT's handling of the iommu master's probe
with deferred probing when the corrsponding iommu is not probed yet.
The lack of a registered IOMMU can be caused by the lack of a driver for
the IOMMU, the IOMMU device probe not having been performed yet, having
been deferred, or having failed.

The first case occurs when the firmware describes the bus master and
IOMMU topology correctly but no device driver exists for the IOMMU yet
or the device driver has not been compiled in. Return NULL, the caller
will configure the device without an IOMMU.

The second and third cases are handled by deferring the probe of the bus
master device which will eventually get reprobed after the IOMMU.

The last case is currently handled by deferring the probe of the bus
master device as well. A mechanism to either configure the bus master
device without an IOMMU or to fail the bus master device probe depending
on whether the IOMMU is optional or mandatory would be a good
enhancement.

Tested-by: Hanjun Guo 
Reviewed-by: Robin Murphy 
[Lorenzo: Added fixes for dma_coherent_mask overflow, acpi_dma_configure
  called multiple times for same device]
Signed-off-by: Lorenzo Pieralisi 
Signed-off-by: Sricharan R 
---
 drivers/acpi/arm64/iort.c  | 33 -
 drivers/acpi/scan.c| 11 ---
 drivers/base/dma-mapping.c |  2 +-
 include/acpi/acpi_bus.h|  2 +-
 include/linux/acpi.h   |  7 +--
 5 files changed, 47 insertions(+), 8 deletions(-)

diff --git a/drivers/acpi/arm64/iort.c b/drivers/acpi/arm64/iort.c
index 3dd9ec3..e323ece 100644
--- a/drivers/acpi/arm64/iort.c
+++ b/drivers/acpi/arm64/iort.c
@@ -543,6 +543,14 @@ static const struct iommu_ops *iort_iommu_xlate(struct 
device *dev,
const struct iommu_ops *ops = NULL;
int ret = -ENODEV;
struct fwnode_handle *iort_fwnode;
+   struct iommu_fwspec *fwspec = dev->iommu_fwspec;
+
+   /*
+* If we already translated the fwspec there
+* is nothing left to do, return the iommu_ops.
+*/
+   if (fwspec && fwspec->ops)
+   return fwspec->ops;
 
if (node) {
iort_fwnode = iort_get_fwnode(node);
@@ -550,8 +558,17 @@ static const struct iommu_ops *iort_iommu_xlate(struct 
device *dev,
return NULL;
 
ops = iommu_ops_from_fwnode(iort_fwnode);
+   /*
+* If the ops look-up fails, this means that either
+* the SMMU drivers have not been probed yet or that
+* the SMMU drivers are not built in the kernel;
+* Depending on whether the SMMU drivers are built-in
+* in the kernel or not, defer the IOMMU configuration
+* or just abort it.
+*/
if (!ops)
-   return NULL;
+   return iort_iommu_driver_enabled(node->type) ?
+  ERR_PTR(-EPROBE_DEFER) : NULL;
 
ret = arm_smmu_iort_xlate(dev, streamid, iort_fwnode, ops);
}
@@ -625,12 +642,26 @@ const struct iommu_ops *iort_iommu_configure(struct 
device *dev)
 
while (parent) {
ops = iort_iommu_xlate(dev, parent, streamid);
+   if (IS_ERR_OR_NULL(ops))
+   return ops;
 
parent = iort_node_get_id(node, ,
  IORT_IOMMU_TYPE, i++);
}
}
 
+   /*
+* If we have reason to believe the IOMMU driver missed the initial
+* add_device callback for dev, replay it to get things in order.
+*/
+   if (!IS_ERR_OR_NULL(ops) && ops->add_device &&
+   dev->bus && !dev->iommu_group) {
+   int err = ops->add_device(dev);
+
+   if (err)
+   ops = ERR_PTR(err);
+   }
+
return ops;
 }
 
diff --git a/drivers/acpi/scan.c b/drivers/acpi/scan.c
index 1926918..2a513cc 100644
--- a/drivers/acpi/scan.c
+++ b/drivers/acpi/scan.c
@@ -1373,20 +1373,25 @@ enum dev_dma_attr acpi_get_dma_attr(struct acpi_device 
*adev)
  * @dev: The pointer to the device
  * @attr: device dma attributes
  */
-void acpi_dma_configure(struct device *dev, enum dev_dma_attr attr)
+int acpi_dma_configure(struct device *dev, enum dev_dma_attr attr)
 {
const struct iommu_ops *iommu;
+   u64 size;
 
iort_set_dma_mask(dev);
 
iommu = iort_iommu_configure(dev);
+   if (IS_ERR(iommu))
+   return PTR_ERR(iommu);
 
+   size = max(dev->coherent_dma_mask, dev->coherent_dma_mask + 1);
/*
 * Assume dma valid range starts at 0 and covers the whole
 * coherent_dma_mask.
 */
-   arch_setup_dma_ops(dev, 0, dev->coherent_dma_mask + 1, iommu,
-

[PATCH V11 08/11] drivers: acpi: Handle IOMMU lookup failure with deferred probing or error

2017-04-10 Thread Sricharan R 
This is an equivalent to the DT's handling of the iommu master's probe
with deferred probing when the corrsponding iommu is not probed yet.
The lack of a registered IOMMU can be caused by the lack of a driver for
the IOMMU, the IOMMU device probe not having been performed yet, having
been deferred, or having failed.

The first case occurs when the firmware describes the bus master and
IOMMU topology correctly but no device driver exists for the IOMMU yet
or the device driver has not been compiled in. Return NULL, the caller
will configure the device without an IOMMU.

The second and third cases are handled by deferring the probe of the bus
master device which will eventually get reprobed after the IOMMU.

The last case is currently handled by deferring the probe of the bus
master device as well. A mechanism to either configure the bus master
device without an IOMMU or to fail the bus master device probe depending
on whether the IOMMU is optional or mandatory would be a good
enhancement.

Tested-by: Hanjun Guo 
Reviewed-by: Robin Murphy 
[Lorenzo: Added fixes for dma_coherent_mask overflow, acpi_dma_configure
  called multiple times for same device]
Signed-off-by: Lorenzo Pieralisi 
Signed-off-by: Sricharan R 
---
 drivers/acpi/arm64/iort.c  | 33 -
 drivers/acpi/scan.c| 11 ---
 drivers/base/dma-mapping.c |  2 +-
 include/acpi/acpi_bus.h|  2 +-
 include/linux/acpi.h   |  7 +--
 5 files changed, 47 insertions(+), 8 deletions(-)

diff --git a/drivers/acpi/arm64/iort.c b/drivers/acpi/arm64/iort.c
index 3dd9ec3..e323ece 100644
--- a/drivers/acpi/arm64/iort.c
+++ b/drivers/acpi/arm64/iort.c
@@ -543,6 +543,14 @@ static const struct iommu_ops *iort_iommu_xlate(struct 
device *dev,
const struct iommu_ops *ops = NULL;
int ret = -ENODEV;
struct fwnode_handle *iort_fwnode;
+   struct iommu_fwspec *fwspec = dev->iommu_fwspec;
+
+   /*
+* If we already translated the fwspec there
+* is nothing left to do, return the iommu_ops.
+*/
+   if (fwspec && fwspec->ops)
+   return fwspec->ops;
 
if (node) {
iort_fwnode = iort_get_fwnode(node);
@@ -550,8 +558,17 @@ static const struct iommu_ops *iort_iommu_xlate(struct 
device *dev,
return NULL;
 
ops = iommu_ops_from_fwnode(iort_fwnode);
+   /*
+* If the ops look-up fails, this means that either
+* the SMMU drivers have not been probed yet or that
+* the SMMU drivers are not built in the kernel;
+* Depending on whether the SMMU drivers are built-in
+* in the kernel or not, defer the IOMMU configuration
+* or just abort it.
+*/
if (!ops)
-   return NULL;
+   return iort_iommu_driver_enabled(node->type) ?
+  ERR_PTR(-EPROBE_DEFER) : NULL;
 
ret = arm_smmu_iort_xlate(dev, streamid, iort_fwnode, ops);
}
@@ -625,12 +642,26 @@ const struct iommu_ops *iort_iommu_configure(struct 
device *dev)
 
while (parent) {
ops = iort_iommu_xlate(dev, parent, streamid);
+   if (IS_ERR_OR_NULL(ops))
+   return ops;
 
parent = iort_node_get_id(node, ,
  IORT_IOMMU_TYPE, i++);
}
}
 
+   /*
+* If we have reason to believe the IOMMU driver missed the initial
+* add_device callback for dev, replay it to get things in order.
+*/
+   if (!IS_ERR_OR_NULL(ops) && ops->add_device &&
+   dev->bus && !dev->iommu_group) {
+   int err = ops->add_device(dev);
+
+   if (err)
+   ops = ERR_PTR(err);
+   }
+
return ops;
 }
 
diff --git a/drivers/acpi/scan.c b/drivers/acpi/scan.c
index 1926918..2a513cc 100644
--- a/drivers/acpi/scan.c
+++ b/drivers/acpi/scan.c
@@ -1373,20 +1373,25 @@ enum dev_dma_attr acpi_get_dma_attr(struct acpi_device 
*adev)
  * @dev: The pointer to the device
  * @attr: device dma attributes
  */
-void acpi_dma_configure(struct device *dev, enum dev_dma_attr attr)
+int acpi_dma_configure(struct device *dev, enum dev_dma_attr attr)
 {
const struct iommu_ops *iommu;
+   u64 size;
 
iort_set_dma_mask(dev);
 
iommu = iort_iommu_configure(dev);
+   if (IS_ERR(iommu))
+   return PTR_ERR(iommu);
 
+   size = max(dev->coherent_dma_mask, dev->coherent_dma_mask + 1);
/*
 * Assume dma valid range starts at 0 and covers the whole
 * coherent_dma_mask.
 */
-   arch_setup_dma_ops(dev, 0, dev->coherent_dma_mask + 1, iommu,
-  attr == DEV_DMA_COHERENT);
+   arch_setup_dma_ops(dev, 0, size, iommu,