Re: [PATCH v2] ACPI/IORT: Make dma masks set-up IORT specific

[Joerg Roedel]

On Tue, Dec 06, 2016 at 02:20:11PM +, Lorenzo Pieralisi wrote:
>  drivers/acpi/arm64/iort.c | 22 ++
>  drivers/acpi/scan.c   | 14 +-
>  include/linux/acpi_iort.h |  2 ++
>  3 files changed, 25 insertions(+), 13 deletions(-)

Applied, thanks.

Re: [PATCH v2] ACPI/IORT: Make dma masks set-up IORT specific

[Joerg Roedel]

On Tue, Dec 06, 2016 at 02:20:11PM +, Lorenzo Pieralisi wrote:
>  drivers/acpi/arm64/iort.c | 22 ++
>  drivers/acpi/scan.c   | 14 +-
>  include/linux/acpi_iort.h |  2 ++
>  3 files changed, 25 insertions(+), 13 deletions(-)

Applied, thanks.

[PATCH v2] ACPI/IORT: Make dma masks set-up IORT specific

[Lorenzo Pieralisi]

The introduction of acpi_dma_configure() allows to configure DMA
and related IOMMU for any device that is DMA capable. To achieve
that goal it ensures DMA masks are set-up to sane default values
before proceeding with IOMMU and DMA ops configuration.

On x86/ia64 systems, through acpi_bind_one(), acpi_dma_configure() is
called for every device that has an ACPI companion, in that every device
is considered DMA capable on x86/ia64 systems (ie acpi_get_dma_attr() API),
which has the side effect of initializing dma masks also for
pseudo-devices (eg CPUs and memory nodes) and potentially for devices
whose dma masks were not set-up before the acpi_dma_configure() API was
introduced, which may have noxious side effects.

Therefore, in preparation for IORT firmware specific DMA masks set-up,
wrap the default DMA masks set-up in acpi_dma_configure() inside an IORT
specific wrapper that reverts to a NOP on x86/ia64 systems, restoring the
default expected behaviour on x86/ia64 systems and keeping DMA default
masks set-up on IORT based (ie ARM) arch configurations.

Signed-off-by: Lorenzo Pieralisi 
Acked-by: Will Deacon 
Acked-by: Rafael J. Wysocki 
Reviewed-by: Hanjun Guo 
Tested-by: Hanjun Guo 
Cc: Will Deacon 
Cc: Hanjun Guo 
Cc: Bjorn Helgaas 
Cc: Robin Murphy 
Cc: Tomasz Nowicki 
Cc: Joerg Roedel 
Cc: "Rafael J. Wysocki" 
Cc: Sricharan R 
---
Hi Joerg,

as discussed please apply it to your arm/smmu branch (and consequently
to -next) in order to get this queued along with the rest of the ACPI IORT
SMMU series for v4.10.

Thank you !
Lorenzo

v1 -> v2
- Added review tags

 drivers/acpi/arm64/iort.c | 22 ++
 drivers/acpi/scan.c   | 14 +-
 include/linux/acpi_iort.h |  2 ++
 3 files changed, 25 insertions(+), 13 deletions(-)

diff --git a/drivers/acpi/arm64/iort.c b/drivers/acpi/arm64/iort.c
index 47bace8..e0d2e6e 100644
--- a/drivers/acpi/arm64/iort.c
+++ b/drivers/acpi/arm64/iort.c
@@ -547,6 +547,28 @@ static const struct iommu_ops *iort_iommu_xlate(struct 
device *dev,
 }
 
 /**
+ * iort_set_dma_mask - Set-up dma mask for a device.
+ *
+ * @dev: device to configure
+ */
+void iort_set_dma_mask(struct device *dev)
+{
+   /*
+* Set default coherent_dma_mask to 32 bit.  Drivers are expected to
+* setup the correct supported mask.
+*/
+   if (!dev->coherent_dma_mask)
+   dev->coherent_dma_mask = DMA_BIT_MASK(32);
+
+   /*
+* Set it to coherent_dma_mask by default if the architecture
+* code has not set it.
+*/
+   if (!dev->dma_mask)
+   dev->dma_mask = >coherent_dma_mask;
+}
+
+/**
  * iort_iommu_configure - Set-up IOMMU configuration for a device.
  *
  * @dev: device to configure
diff --git a/drivers/acpi/scan.c b/drivers/acpi/scan.c
index 80698d3..93b00cf 100644
--- a/drivers/acpi/scan.c
+++ b/drivers/acpi/scan.c
@@ -1380,19 +1380,7 @@ void acpi_dma_configure(struct device *dev, enum 
dev_dma_attr attr)
 {
const struct iommu_ops *iommu;
 
-   /*
-* Set default coherent_dma_mask to 32 bit.  Drivers are expected to
-* setup the correct supported mask.
-*/
-   if (!dev->coherent_dma_mask)
-   dev->coherent_dma_mask = DMA_BIT_MASK(32);
-
-   /*
-* Set it to coherent_dma_mask by default if the architecture
-* code has not set it.
-*/
-   if (!dev->dma_mask)
-   dev->dma_mask = >coherent_dma_mask;
+   iort_set_dma_mask(dev);
 
iommu = iort_iommu_configure(dev);
 
diff --git a/include/linux/acpi_iort.h b/include/linux/acpi_iort.h
index dcb2b60..77e0809 100644
--- a/include/linux/acpi_iort.h
+++ b/include/linux/acpi_iort.h
@@ -35,6 +35,7 @@ bool iort_node_match(u8 type);
 u32 iort_msi_map_rid(struct device *dev, u32 req_id);
 struct irq_domain *iort_get_device_domain(struct device *dev, u32 req_id);
 /* IOMMU interface */
+void iort_set_dma_mask(struct device *dev);
 const struct iommu_ops *iort_iommu_configure(struct device *dev);
 #else
 static inline void acpi_iort_init(void) { }
@@ -45,6 +46,7 @@ static inline struct irq_domain 
*iort_get_device_domain(struct device *dev,
u32 req_id)
 { return NULL; }
 /* IOMMU interface */
+static inline void iort_set_dma_mask(struct device *dev) { }
 static inline
 const struct iommu_ops *iort_iommu_configure(struct device *dev)
 { return NULL; }
-- 
2.10.0

[PATCH v2] ACPI/IORT: Make dma masks set-up IORT specific

[Lorenzo Pieralisi]

The introduction of acpi_dma_configure() allows to configure DMA
and related IOMMU for any device that is DMA capable. To achieve
that goal it ensures DMA masks are set-up to sane default values
before proceeding with IOMMU and DMA ops configuration.

On x86/ia64 systems, through acpi_bind_one(), acpi_dma_configure() is
called for every device that has an ACPI companion, in that every device
is considered DMA capable on x86/ia64 systems (ie acpi_get_dma_attr() API),
which has the side effect of initializing dma masks also for
pseudo-devices (eg CPUs and memory nodes) and potentially for devices
whose dma masks were not set-up before the acpi_dma_configure() API was
introduced, which may have noxious side effects.

Therefore, in preparation for IORT firmware specific DMA masks set-up,
wrap the default DMA masks set-up in acpi_dma_configure() inside an IORT
specific wrapper that reverts to a NOP on x86/ia64 systems, restoring the
default expected behaviour on x86/ia64 systems and keeping DMA default
masks set-up on IORT based (ie ARM) arch configurations.

Signed-off-by: Lorenzo Pieralisi 
Acked-by: Will Deacon 
Acked-by: Rafael J. Wysocki 
Reviewed-by: Hanjun Guo 
Tested-by: Hanjun Guo 
Cc: Will Deacon 
Cc: Hanjun Guo 
Cc: Bjorn Helgaas 
Cc: Robin Murphy 
Cc: Tomasz Nowicki 
Cc: Joerg Roedel 
Cc: "Rafael J. Wysocki" 
Cc: Sricharan R 
---
Hi Joerg,

as discussed please apply it to your arm/smmu branch (and consequently
to -next) in order to get this queued along with the rest of the ACPI IORT
SMMU series for v4.10.

Thank you !
Lorenzo

v1 -> v2
- Added review tags

 drivers/acpi/arm64/iort.c | 22 ++
 drivers/acpi/scan.c   | 14 +-
 include/linux/acpi_iort.h |  2 ++
 3 files changed, 25 insertions(+), 13 deletions(-)

diff --git a/drivers/acpi/arm64/iort.c b/drivers/acpi/arm64/iort.c
index 47bace8..e0d2e6e 100644
--- a/drivers/acpi/arm64/iort.c
+++ b/drivers/acpi/arm64/iort.c
@@ -547,6 +547,28 @@ static const struct iommu_ops *iort_iommu_xlate(struct 
device *dev,
 }
 
 /**
+ * iort_set_dma_mask - Set-up dma mask for a device.
+ *
+ * @dev: device to configure
+ */
+void iort_set_dma_mask(struct device *dev)
+{
+   /*
+* Set default coherent_dma_mask to 32 bit.  Drivers are expected to
+* setup the correct supported mask.
+*/
+   if (!dev->coherent_dma_mask)
+   dev->coherent_dma_mask = DMA_BIT_MASK(32);
+
+   /*
+* Set it to coherent_dma_mask by default if the architecture
+* code has not set it.
+*/
+   if (!dev->dma_mask)
+   dev->dma_mask = >coherent_dma_mask;
+}
+
+/**
  * iort_iommu_configure - Set-up IOMMU configuration for a device.
  *
  * @dev: device to configure
diff --git a/drivers/acpi/scan.c b/drivers/acpi/scan.c
index 80698d3..93b00cf 100644
--- a/drivers/acpi/scan.c
+++ b/drivers/acpi/scan.c
@@ -1380,19 +1380,7 @@ void acpi_dma_configure(struct device *dev, enum 
dev_dma_attr attr)
 {
const struct iommu_ops *iommu;
 
-   /*
-* Set default coherent_dma_mask to 32 bit.  Drivers are expected to
-* setup the correct supported mask.
-*/
-   if (!dev->coherent_dma_mask)
-   dev->coherent_dma_mask = DMA_BIT_MASK(32);
-
-   /*
-* Set it to coherent_dma_mask by default if the architecture
-* code has not set it.
-*/
-   if (!dev->dma_mask)
-   dev->dma_mask = >coherent_dma_mask;
+   iort_set_dma_mask(dev);
 
iommu = iort_iommu_configure(dev);
 
diff --git a/include/linux/acpi_iort.h b/include/linux/acpi_iort.h
index dcb2b60..77e0809 100644
--- a/include/linux/acpi_iort.h
+++ b/include/linux/acpi_iort.h
@@ -35,6 +35,7 @@ bool iort_node_match(u8 type);
 u32 iort_msi_map_rid(struct device *dev, u32 req_id);
 struct irq_domain *iort_get_device_domain(struct device *dev, u32 req_id);
 /* IOMMU interface */
+void iort_set_dma_mask(struct device *dev);
 const struct iommu_ops *iort_iommu_configure(struct device *dev);
 #else
 static inline void acpi_iort_init(void) { }
@@ -45,6 +46,7 @@ static inline struct irq_domain 
*iort_get_device_domain(struct device *dev,
u32 req_id)
 { return NULL; }
 /* IOMMU interface */
+static inline void iort_set_dma_mask(struct device *dev) { }
 static inline
 const struct iommu_ops *iort_iommu_configure(struct device *dev)
 { return NULL; }
-- 
2.10.0