[PATCH v5 0/8] PCI: get DMA configuration from parent device

[PATCH v5 0/8] PCI: get DMA configuration from parent device

[Murali Karicheri]

PCI devices on Keystone doesn't have correct dma_pfn_offset set. This patch
add capability to set the dma configuration such as dma-mask, dma_pfn_offset,
and dma ops etc using the information from DT. The prior RFCs and discussions
are available at [1] and [2] below.

[2] : https://www.mail-archive.com/linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org/msg790244.html
[1] : http://www.gossamer-threads.com/lists/linux/kernel/2024591

Change history:
	v5 - moved the dma_mask update in device from ARM specific API to
	     of_dma_configure to allow this across other architecture as well
	   - improved sanity check for DT dma-range size in of_dma_configure()
	   - moved API to get parent bridge device to PCI (host-bridge.c)
	v4 - moved size adjustments in of_iommu_configure() to a separate patch
	   - consistent node name comment from Rob
	   - patch 6 added for dma_mask adjustment and iommu mapping size
	     limiting.
	v3 - addressed comments to re-use of_dma_configure() for PCI
	   - To help re-use, change of_iommu_configure() function argument
		- Move of_dma_configure to of/device.c
		- Limit the of_iommu_configure to non pci devices
	v2 - update size to coherent_dma_mask + 1 if dma-range info is missing
	   - also check the np for null.
	v1 - updates based on the comments against initial RFC.
	   - Added a helper function to get the OF node of the parent
	   - Added an API in of_pci.c to update DMA configuration of the pci
	     device.

Cc: Joerg Roedel <joro-zLv9SwRftAIdnm+yROfE0A@public.gmane.org>
Cc: Grant Likely <grant.likely-QSEj5FYQhm4dnm+yROfE0A@public.gmane.org>
Cc: Rob Herring <robh+dt-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org>
Cc: Bjorn Helgaas <bhelgaas-hpIqsD4AKlfQT0dZR+AlfA@public.gmane.org>
Cc: Will Deacon <will.deacon-5wv7dgnIgG8@public.gmane.org>
Cc: Russell King <linux-lFZ/pmaqli7XmaaqVzeoHQ@public.gmane.org>
Cc: Arnd Bergmann <arnd-r2nGTMty4D4@public.gmane.org>
Cc: Suravee Suthikulpanit <Suravee.Suthikulpanit-5C7GfCeVMHo@public.gmane.org>

Acked-by: Bjorn Helgaas <bhelgaas-hpIqsD4AKlfQT0dZR+AlfA@public.gmane.org>
Acked-by: Murali Karicheri <m-karicheri2-l0cyMroinI0@public.gmane.org>

Murali Karicheri (8):
  of: iommu: add ptr to OF node arg to of_iommu_configure()
  of: move of_dma_configure() to device.c to help re-use
  of: fix size when dma-range is not used
  PCI: add helper functions pci_get[put]_host_bridge_device()
  of/pci: add of_pci_dma_configure() update dma configuration
  PCI: update dma configuration from DT
  arm: dma-mapping: limit iommu mapping size
  of: limit dma_mask of the device based on dma-range size

 arch/arm/mm/dma-mapping.c |    7 +++++
 drivers/iommu/of_iommu.c  |   10 +++++--
 drivers/of/device.c       |   69 +++++++++++++++++++++++++++++++++++++++++++++
 drivers/of/of_pci.c       |   19 +++++++++++++
 drivers/of/platform.c     |   58 ++-----------------------------------
 drivers/pci/host-bridge.c |   14 +++++++++
 drivers/pci/probe.c       |    2 ++
 include/linux/of_device.h |    2 ++
 include/linux/of_iommu.h  |    6 ++--
 include/linux/of_pci.h    |    5 ++++
 include/linux/pci.h       |    3 ++
 11 files changed, 135 insertions(+), 60 deletions(-)

-- 
1.7.9.5

--
To unsubscribe from this list: send the line "unsubscribe devicetree" in
the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html

[PATCH v5 1/8] of: iommu: add ptr to OF node arg to of_iommu_configure()

[Murali Karicheri]

Function of_iommu_configure() is called from of_dma_configure() to
setup iommu ops using DT property. This API is currently used for
platform devices for which DMA configuration (including iommu ops)
may come from device's parent. To extend this functionality for PCI
devices, this API need to take a parent node ptr as an argument
instead of assuming device's parent. This is needed since for PCI, the
dma configuration may be defined in the DT node of the root bus bridge's
parent device. Currently only dma-range is used for PCI and iommu is not
supported. So return error if the device is PCI.

Cc: Joerg Roedel <joro@8bytes.org>
Cc: Grant Likely <grant.likely@linaro.org>
Cc: Rob Herring <robh+dt@kernel.org>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Suravee Suthikulpanit <Suravee.Suthikulpanit@amd.com>

Acked-by: Bjorn Helgaas <bhelgaas@google.com>
Signed-off-by: Murali Karicheri <m-karicheri2@ti.com>
---
 drivers/iommu/of_iommu.c |   10 ++++++++--
 drivers/of/platform.c    |    2 +-
 include/linux/of_iommu.h |    6 ++++--
 3 files changed, 13 insertions(+), 5 deletions(-)

diff --git a/drivers/iommu/of_iommu.c b/drivers/iommu/of_iommu.c
index af1dc6a..439235b 100644
--- a/drivers/iommu/of_iommu.c
+++ b/drivers/iommu/of_iommu.c
@@ -133,19 +133,25 @@ struct iommu_ops *of_iommu_get_ops(struct device_node *np)
 	return ops;
 }
 
-struct iommu_ops *of_iommu_configure(struct device *dev)
+struct iommu_ops *of_iommu_configure(struct device *dev,
+				     struct device_node *iommu_np)
 {
 	struct of_phandle_args iommu_spec;
 	struct device_node *np;
 	struct iommu_ops *ops = NULL;
 	int idx = 0;
 
+	if (dev_is_pci(dev)) {
+		dev_err(dev, "iommu is currently not supported for PCI\n");
+		return NULL;
+	}
+
 	/*
 	 * We don't currently walk up the tree looking for a parent IOMMU.
 	 * See the `Notes:' section of
 	 * Documentation/devicetree/bindings/iommu/iommu.txt
 	 */
-	while (!of_parse_phandle_with_args(dev->of_node, "iommus",
+	while (!of_parse_phandle_with_args(iommu_np, "iommus",
 					   "#iommu-cells", idx,
 					   &iommu_spec)) {
 		np = iommu_spec.np;
diff --git a/drivers/of/platform.c b/drivers/of/platform.c
index b0d50d7..d3f3988 100644
--- a/drivers/of/platform.c
+++ b/drivers/of/platform.c
@@ -196,7 +196,7 @@ static void of_dma_configure(struct device *dev)
 	dev_dbg(dev, "device is%sdma coherent\n",
 		coherent ? " " : " not ");
 
-	iommu = of_iommu_configure(dev);
+	iommu = of_iommu_configure(dev, dev->of_node);
 	dev_dbg(dev, "device is%sbehind an iommu\n",
 		iommu ? " " : " not ");
 
diff --git a/include/linux/of_iommu.h b/include/linux/of_iommu.h
index 16c7554..a97e5bd 100644
--- a/include/linux/of_iommu.h
+++ b/include/linux/of_iommu.h
@@ -12,7 +12,8 @@ extern int of_get_dma_window(struct device_node *dn, const char *prefix,
 			     size_t *size);
 
 extern void of_iommu_init(void);
-extern struct iommu_ops *of_iommu_configure(struct device *dev);
+extern struct iommu_ops *of_iommu_configure(struct device *dev,
+					struct device_node *iommu_np);
 
 #else
 
@@ -24,7 +25,8 @@ static inline int of_get_dma_window(struct device_node *dn, const char *prefix,
 }
 
 static inline void of_iommu_init(void) { }
-static inline struct iommu_ops *of_iommu_configure(struct device *dev)
+static inline struct iommu_ops *of_iommu_configure(struct device *dev,
+					 struct device_node *iommu_np)
 {
 	return NULL;
 }
-- 
1.7.9.5

Re: [PATCH v5 1/8] of: iommu: add ptr to OF node arg to of_iommu_configure()

[Rob Herring]

On Tue, Jan 27, 2015 at 2:59 PM, Murali Karicheri <m-karicheri2-l0cyMroinI0@public.gmane.org> wrote:
> Function of_iommu_configure() is called from of_dma_configure() to
> setup iommu ops using DT property. This API is currently used for
> platform devices for which DMA configuration (including iommu ops)
> may come from device's parent. To extend this functionality for PCI
> devices, this API need to take a parent node ptr as an argument
> instead of assuming device's parent. This is needed since for PCI, the
> dma configuration may be defined in the DT node of the root bus bridge's
> parent device. Currently only dma-range is used for PCI and iommu is not
> supported. So return error if the device is PCI.
>
> Cc: Joerg Roedel <joro-zLv9SwRftAIdnm+yROfE0A@public.gmane.org>
> Cc: Grant Likely <grant.likely-QSEj5FYQhm4dnm+yROfE0A@public.gmane.org>
> Cc: Rob Herring <robh+dt-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org>

Acked-by: Rob Herring <robh-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org>

> Cc: Will Deacon <will.deacon-5wv7dgnIgG8@public.gmane.org>
> Cc: Russell King <linux-lFZ/pmaqli7XmaaqVzeoHQ@public.gmane.org>
> Cc: Arnd Bergmann <arnd-r2nGTMty4D4@public.gmane.org>
> Cc: Suravee Suthikulpanit <Suravee.Suthikulpanit-5C7GfCeVMHo@public.gmane.org>
>
> Acked-by: Bjorn Helgaas <bhelgaas-hpIqsD4AKlfQT0dZR+AlfA@public.gmane.org>
> Signed-off-by: Murali Karicheri <m-karicheri2-l0cyMroinI0@public.gmane.org>
> ---
>  drivers/iommu/of_iommu.c |   10 ++++++++--
>  drivers/of/platform.c    |    2 +-
>  include/linux/of_iommu.h |    6 ++++--
>  3 files changed, 13 insertions(+), 5 deletions(-)
>
> diff --git a/drivers/iommu/of_iommu.c b/drivers/iommu/of_iommu.c
> index af1dc6a..439235b 100644
> --- a/drivers/iommu/of_iommu.c
> +++ b/drivers/iommu/of_iommu.c
> @@ -133,19 +133,25 @@ struct iommu_ops *of_iommu_get_ops(struct device_node *np)
>         return ops;
>  }
>
> -struct iommu_ops *of_iommu_configure(struct device *dev)
> +struct iommu_ops *of_iommu_configure(struct device *dev,
> +                                    struct device_node *iommu_np)
>  {
>         struct of_phandle_args iommu_spec;
>         struct device_node *np;
>         struct iommu_ops *ops = NULL;
>         int idx = 0;
>
> +       if (dev_is_pci(dev)) {
> +               dev_err(dev, "iommu is currently not supported for PCI\n");
> +               return NULL;
> +       }
> +
>         /*
>          * We don't currently walk up the tree looking for a parent IOMMU.
>          * See the `Notes:' section of
>          * Documentation/devicetree/bindings/iommu/iommu.txt
>          */
> -       while (!of_parse_phandle_with_args(dev->of_node, "iommus",
> +       while (!of_parse_phandle_with_args(iommu_np, "iommus",
>                                            "#iommu-cells", idx,
>                                            &iommu_spec)) {
>                 np = iommu_spec.np;
> diff --git a/drivers/of/platform.c b/drivers/of/platform.c
> index b0d50d7..d3f3988 100644
> --- a/drivers/of/platform.c
> +++ b/drivers/of/platform.c
> @@ -196,7 +196,7 @@ static void of_dma_configure(struct device *dev)
>         dev_dbg(dev, "device is%sdma coherent\n",
>                 coherent ? " " : " not ");
>
> -       iommu = of_iommu_configure(dev);
> +       iommu = of_iommu_configure(dev, dev->of_node);
>         dev_dbg(dev, "device is%sbehind an iommu\n",
>                 iommu ? " " : " not ");
>
> diff --git a/include/linux/of_iommu.h b/include/linux/of_iommu.h
> index 16c7554..a97e5bd 100644
> --- a/include/linux/of_iommu.h
> +++ b/include/linux/of_iommu.h
> @@ -12,7 +12,8 @@ extern int of_get_dma_window(struct device_node *dn, const char *prefix,
>                              size_t *size);
>
>  extern void of_iommu_init(void);
> -extern struct iommu_ops *of_iommu_configure(struct device *dev);
> +extern struct iommu_ops *of_iommu_configure(struct device *dev,
> +                                       struct device_node *iommu_np);
>
>  #else
>
> @@ -24,7 +25,8 @@ static inline int of_get_dma_window(struct device_node *dn, const char *prefix,
>  }
>
>  static inline void of_iommu_init(void) { }
> -static inline struct iommu_ops *of_iommu_configure(struct device *dev)
> +static inline struct iommu_ops *of_iommu_configure(struct device *dev,
> +                                        struct device_node *iommu_np)
>  {
>         return NULL;
>  }
> --
> 1.7.9.5
>

[PATCH v5 2/8] of: move of_dma_configure() to device.c to help re-use

[Murali Karicheri]

Move of_dma_configure() to device.c so that same function can be re-used
for PCI devices to obtain DMA configuration from DT. Also add a second
argument so that for PCI, DT node of root bus host bridge can be used to
obtain the DMA configuration for the slave PCI device.

Cc: Joerg Roedel <joro-zLv9SwRftAIdnm+yROfE0A@public.gmane.org>
Cc: Grant Likely <grant.likely-QSEj5FYQhm4dnm+yROfE0A@public.gmane.org>
Cc: Rob Herring <robh+dt-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org>
Cc: Will Deacon <will.deacon-5wv7dgnIgG8@public.gmane.org>
Cc: Russell King <linux-lFZ/pmaqli7XmaaqVzeoHQ@public.gmane.org>
Cc: Arnd Bergmann <arnd-r2nGTMty4D4@public.gmane.org>
Cc: Suravee Suthikulpanit <Suravee.Suthikulpanit-5C7GfCeVMHo@public.gmane.org>

Acked-by: Bjorn Helgaas <bhelgaas-hpIqsD4AKlfQT0dZR+AlfA@public.gmane.org>
Signed-off-by: Murali Karicheri <m-karicheri2-l0cyMroinI0@public.gmane.org>
---
 drivers/of/device.c       |   59 +++++++++++++++++++++++++++++++++++++++++++++
 drivers/of/platform.c     |   58 ++------------------------------------------
 include/linux/of_device.h |    2 ++
 3 files changed, 63 insertions(+), 56 deletions(-)

diff --git a/drivers/of/device.c b/drivers/of/device.c
index 46d6c75c..2de320d 100644
--- a/drivers/of/device.c
+++ b/drivers/of/device.c
@@ -2,6 +2,9 @@
 #include <linux/kernel.h>
 #include <linux/of.h>
 #include <linux/of_device.h>
+#include <linux/of_address.h>
+#include <linux/of_iommu.h>
+#include <linux/dma-mapping.h>
 #include <linux/init.h>
 #include <linux/module.h>
 #include <linux/mod_devicetable.h>
@@ -66,6 +69,62 @@ int of_device_add(struct platform_device *ofdev)
 	return device_add(&ofdev->dev);
 }
 
+/**
+ * of_dma_configure - Setup DMA configuration
+ * @dev:	Device to apply DMA configuration
+ * @np:		ptr to of node having dma configuration
+ *
+ * Try to get devices's DMA configuration from DT and update it
+ * accordingly.
+ *
+ * In case if platform code need to use own special DMA configuration,it
+ * can use Platform bus notifier and handle BUS_NOTIFY_ADD_DEVICE event
+ * to fix up DMA configuration.
+ */
+void of_dma_configure(struct device *dev, struct device_node *np)
+{
+	u64 dma_addr, paddr, size;
+	int ret;
+	bool coherent;
+	unsigned long offset;
+	struct iommu_ops *iommu;
+
+	/*
+	 * Set default dma-mask to 32 bit. Drivers are expected to setup
+	 * the correct supported 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 = &dev->coherent_dma_mask;
+
+	ret = of_dma_get_range(np, &dma_addr, &paddr, &size);
+	if (ret < 0) {
+		dma_addr = offset = 0;
+		size = dev->coherent_dma_mask;
+	} else {
+		offset = PFN_DOWN(paddr - dma_addr);
+		dev_dbg(dev, "dma_pfn_offset(%#08lx)\n", offset);
+	}
+
+	dev->dma_pfn_offset = offset;
+
+	coherent = of_dma_is_coherent(np);
+	dev_dbg(dev, "device is%sdma coherent\n",
+		coherent ? " " : " not ");
+
+	iommu = of_iommu_configure(dev, np);
+	dev_dbg(dev, "device is%sbehind an iommu\n",
+		iommu ? " " : " not ");
+
+	arch_setup_dma_ops(dev, dma_addr, size, iommu, coherent);
+}
+EXPORT_SYMBOL_GPL(of_dma_configure);
+
 int of_device_register(struct platform_device *pdev)
 {
 	device_initialize(&pdev->dev);
diff --git a/drivers/of/platform.c b/drivers/of/platform.c
index d3f3988..cbee18d 100644
--- a/drivers/of/platform.c
+++ b/drivers/of/platform.c
@@ -19,7 +19,6 @@
 #include <linux/slab.h>
 #include <linux/of_address.h>
 #include <linux/of_device.h>
-#include <linux/of_iommu.h>
 #include <linux/of_irq.h>
 #include <linux/of_platform.h>
 #include <linux/platform_device.h>
@@ -150,59 +149,6 @@ struct platform_device *of_device_alloc(struct device_node *np,
 }
 EXPORT_SYMBOL(of_device_alloc);
 
-/**
- * of_dma_configure - Setup DMA configuration
- * @dev:	Device to apply DMA configuration
- *
- * Try to get devices's DMA configuration from DT and update it
- * accordingly.
- *
- * In case if platform code need to use own special DMA configuration,it
- * can use Platform bus notifier and handle BUS_NOTIFY_ADD_DEVICE event
- * to fix up DMA configuration.
- */
-static void of_dma_configure(struct device *dev)
-{
-	u64 dma_addr, paddr, size;
-	int ret;
-	bool coherent;
-	unsigned long offset;
-	struct iommu_ops *iommu;
-
-	/*
-	 * Set default dma-mask to 32 bit. Drivers are expected to setup
-	 * the correct supported 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 = &dev->coherent_dma_mask;
-
-	ret = of_dma_get_range(dev->of_node, &dma_addr, &paddr, &size);
-	if (ret < 0) {
-		dma_addr = offset = 0;
-		size = dev->coherent_dma_mask;
-	} else {
-		offset = PFN_DOWN(paddr - dma_addr);
-		dev_dbg(dev, "dma_pfn_offset(%#08lx)\n", offset);
-	}
-	dev->dma_pfn_offset = offset;
-
-	coherent = of_dma_is_coherent(dev->of_node);
-	dev_dbg(dev, "device is%sdma coherent\n",
-		coherent ? " " : " not ");
-
-	iommu = of_iommu_configure(dev, dev->of_node);
-	dev_dbg(dev, "device is%sbehind an iommu\n",
-		iommu ? " " : " not ");
-
-	arch_setup_dma_ops(dev, dma_addr, size, iommu, coherent);
-}
-
 static void of_dma_deconfigure(struct device *dev)
 {
 	arch_teardown_dma_ops(dev);
@@ -236,7 +182,7 @@ static struct platform_device *of_platform_device_create_pdata(
 
 	dev->dev.bus = &platform_bus_type;
 	dev->dev.platform_data = platform_data;
-	of_dma_configure(&dev->dev);
+	of_dma_configure(&dev->dev, dev->dev.of_node);
 
 	if (of_device_add(dev) != 0) {
 		of_dma_deconfigure(&dev->dev);
@@ -299,7 +245,7 @@ static struct amba_device *of_amba_device_create(struct device_node *node,
 		dev_set_name(&dev->dev, "%s", bus_id);
 	else
 		of_device_make_bus_id(&dev->dev);
-	of_dma_configure(&dev->dev);
+	of_dma_configure(&dev->dev, dev->dev.of_node);
 
 	/* Allow the HW Peripheral ID to be overridden */
 	prop = of_get_property(node, "arm,primecell-periphid", NULL);
diff --git a/include/linux/of_device.h b/include/linux/of_device.h
index ef37021..c661496 100644
--- a/include/linux/of_device.h
+++ b/include/linux/of_device.h
@@ -53,6 +53,7 @@ static inline struct device_node *of_cpu_device_node_get(int cpu)
 	return of_node_get(cpu_dev->of_node);
 }
 
+void of_dma_configure(struct device *dev, struct device_node *np);
 #else /* CONFIG_OF */
 
 static inline int of_driver_match_device(struct device *dev,
@@ -90,6 +91,7 @@ static inline struct device_node *of_cpu_device_node_get(int cpu)
 {
 	return NULL;
 }
+void of_dma_configure(struct device *dev, struct device_node *np) { }
 #endif /* CONFIG_OF */
 
 #endif /* _LINUX_OF_DEVICE_H */
-- 
1.7.9.5

[PATCH v5 3/8] of: fix size when dma-range is not used

[Murali Karicheri]

Fix the dma-range size when the DT attribute is missing. i.e  set size to
dev->coherent_dma_mask + 1 instead of dev->coherent_dma_mask. Also add
code to check invalid values of size configured in DT and log error.

Cc: Joerg Roedel <joro-zLv9SwRftAIdnm+yROfE0A@public.gmane.org>
Cc: Grant Likely <grant.likely-QSEj5FYQhm4dnm+yROfE0A@public.gmane.org>
Cc: Rob Herring <robh+dt-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org>
Cc: Bjorn Helgaas <bhelgaas-hpIqsD4AKlfQT0dZR+AlfA@public.gmane.org>
Cc: Will Deacon <will.deacon-5wv7dgnIgG8@public.gmane.org>
Cc: Russell King <linux-lFZ/pmaqli7XmaaqVzeoHQ@public.gmane.org>
Cc: Arnd Bergmann <arnd-r2nGTMty4D4@public.gmane.org>
Cc: Suravee Suthikulpanit <Suravee.Suthikulpanit-5C7GfCeVMHo@public.gmane.org>

Signed-off-by: Murali Karicheri <m-karicheri2-l0cyMroinI0@public.gmane.org>
---
 drivers/of/device.c |    9 ++++++++-
 1 file changed, 8 insertions(+), 1 deletion(-)

diff --git a/drivers/of/device.c b/drivers/of/device.c
index 2de320d..17504f4 100644
--- a/drivers/of/device.c
+++ b/drivers/of/device.c
@@ -105,12 +105,19 @@ void of_dma_configure(struct device *dev, struct device_node *np)
 	ret = of_dma_get_range(np, &dma_addr, &paddr, &size);
 	if (ret < 0) {
 		dma_addr = offset = 0;
-		size = dev->coherent_dma_mask;
+		size = dev->coherent_dma_mask + 1;
 	} else {
 		offset = PFN_DOWN(paddr - dma_addr);
 		dev_dbg(dev, "dma_pfn_offset(%#08lx)\n", offset);
 	}
 
+	if (is_power_of_2(size + 1))
+		size = size + 1;
+	else if (!is_power_of_2(size)) {
+		dev_err(dev, "invalid size\n");
+		return;
+	}
+
 	dev->dma_pfn_offset = offset;
 
 	coherent = of_dma_is_coherent(np);
-- 
1.7.9.5

Re: [PATCH v5 3/8] of: fix size when dma-range is not used

[Rob Herring]

On Tue, Jan 27, 2015 at 3:00 PM, Murali Karicheri <m-karicheri2-l0cyMroinI0@public.gmane.org> wrote:
> Fix the dma-range size when the DT attribute is missing. i.e  set size to
> dev->coherent_dma_mask + 1 instead of dev->coherent_dma_mask. Also add
> code to check invalid values of size configured in DT and log error.
>
> Cc: Joerg Roedel <joro-zLv9SwRftAIdnm+yROfE0A@public.gmane.org>
> Cc: Grant Likely <grant.likely-QSEj5FYQhm4dnm+yROfE0A@public.gmane.org>
> Cc: Rob Herring <robh+dt-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org>
> Cc: Bjorn Helgaas <bhelgaas-hpIqsD4AKlfQT0dZR+AlfA@public.gmane.org>
> Cc: Will Deacon <will.deacon-5wv7dgnIgG8@public.gmane.org>
> Cc: Russell King <linux-lFZ/pmaqli7XmaaqVzeoHQ@public.gmane.org>
> Cc: Arnd Bergmann <arnd-r2nGTMty4D4@public.gmane.org>
> Cc: Suravee Suthikulpanit <Suravee.Suthikulpanit-5C7GfCeVMHo@public.gmane.org>
>
> Signed-off-by: Murali Karicheri <m-karicheri2-l0cyMroinI0@public.gmane.org>
> ---
>  drivers/of/device.c |    9 ++++++++-
>  1 file changed, 8 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/of/device.c b/drivers/of/device.c
> index 2de320d..17504f4 100644
> --- a/drivers/of/device.c
> +++ b/drivers/of/device.c
> @@ -105,12 +105,19 @@ void of_dma_configure(struct device *dev, struct device_node *np)
>         ret = of_dma_get_range(np, &dma_addr, &paddr, &size);
>         if (ret < 0) {
>                 dma_addr = offset = 0;
> -               size = dev->coherent_dma_mask;
> +               size = dev->coherent_dma_mask + 1;

This is fine since coherent_dma_mask will always be 4G - 1 in this case.

>         } else {
>                 offset = PFN_DOWN(paddr - dma_addr);
>                 dev_dbg(dev, "dma_pfn_offset(%#08lx)\n", offset);
>         }
>
> +       if (is_power_of_2(size + 1))
> +               size = size + 1;
> +       else if (!is_power_of_2(size)) {
> +               dev_err(dev, "invalid size\n");
> +               return;

I think this is too restrictive. I think checking bit 0 is 1 is enough
to tell the size is a mask.

I would like it to be a WARN if detected and just add 1.

Rob

Re: [PATCH v5 3/8] of: fix size when dma-range is not used

[Robin Murphy]

Hi Murali,

[sorry, missed replying to yesterday's version]

On 27/01/15 21:00, Murali Karicheri wrote:
> Fix the dma-range size when the DT attribute is missing. i.e  set size to
> dev->coherent_dma_mask + 1 instead of dev->coherent_dma_mask. Also add
> code to check invalid values of size configured in DT and log error.
>
> Cc: Joerg Roedel <joro-zLv9SwRftAIdnm+yROfE0A@public.gmane.org>
> Cc: Grant Likely <grant.likely-QSEj5FYQhm4dnm+yROfE0A@public.gmane.org>
> Cc: Rob Herring <robh+dt-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org>
> Cc: Bjorn Helgaas <bhelgaas-hpIqsD4AKlfQT0dZR+AlfA@public.gmane.org>
> Cc: Will Deacon <will.deacon-5wv7dgnIgG8@public.gmane.org>
> Cc: Russell King <linux-lFZ/pmaqli7XmaaqVzeoHQ@public.gmane.org>
> Cc: Arnd Bergmann <arnd-r2nGTMty4D4@public.gmane.org>
> Cc: Suravee Suthikulpanit <Suravee.Suthikulpanit-5C7GfCeVMHo@public.gmane.org>
>
> Signed-off-by: Murali Karicheri <m-karicheri2-l0cyMroinI0@public.gmane.org>
> ---
>   drivers/of/device.c |    9 ++++++++-
>   1 file changed, 8 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/of/device.c b/drivers/of/device.c
> index 2de320d..17504f4 100644
> --- a/drivers/of/device.c
> +++ b/drivers/of/device.c
> @@ -105,12 +105,19 @@ void of_dma_configure(struct device *dev, struct device_node *np)
>   	ret = of_dma_get_range(np, &dma_addr, &paddr, &size);
>   	if (ret < 0) {
>   		dma_addr = offset = 0;
> -		size = dev->coherent_dma_mask;
> +		size = dev->coherent_dma_mask + 1;
>   	} else {
>   		offset = PFN_DOWN(paddr - dma_addr);
>   		dev_dbg(dev, "dma_pfn_offset(%#08lx)\n", offset);
>   	}
>
> +	if (is_power_of_2(size + 1))
> +		size = size + 1;
> +	else if (!is_power_of_2(size)) {
> +		dev_err(dev, "invalid size\n");
> +		return;
> +	}
> +

Couldn't these checks go into the "else" path above? We don't need to 
check the non-DT case, because we know we've just set it to something 
sensible.

Robin.

>   	dev->dma_pfn_offset = offset;
>
>   	coherent = of_dma_is_coherent(np);
>

Re: [PATCH v5 3/8] of: fix size when dma-range is not used

[Murali Karicheri]

On 01/28/2015 06:21 AM, Robin Murphy wrote:
> Hi Murali,
>
> [sorry, missed replying to yesterday's version]
>
> On 27/01/15 21:00, Murali Karicheri wrote:
>> Fix the dma-range size when the DT attribute is missing. i.e set size to
>> dev->coherent_dma_mask + 1 instead of dev->coherent_dma_mask. Also add
>> code to check invalid values of size configured in DT and log error.
>>
>> Cc: Joerg Roedel <joro-zLv9SwRftAIdnm+yROfE0A@public.gmane.org>
>> Cc: Grant Likely <grant.likely-QSEj5FYQhm4dnm+yROfE0A@public.gmane.org>
>> Cc: Rob Herring <robh+dt-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org>
>> Cc: Bjorn Helgaas <bhelgaas-hpIqsD4AKlfQT0dZR+AlfA@public.gmane.org>
>> Cc: Will Deacon <will.deacon-5wv7dgnIgG8@public.gmane.org>
>> Cc: Russell King <linux-lFZ/pmaqli7XmaaqVzeoHQ@public.gmane.org>
>> Cc: Arnd Bergmann <arnd-r2nGTMty4D4@public.gmane.org>
>> Cc: Suravee Suthikulpanit <Suravee.Suthikulpanit-5C7GfCeVMHo@public.gmane.org>
>>
>> Signed-off-by: Murali Karicheri <m-karicheri2-l0cyMroinI0@public.gmane.org>
>> ---
>> drivers/of/device.c | 9 ++++++++-
>> 1 file changed, 8 insertions(+), 1 deletion(-)
>>
>> diff --git a/drivers/of/device.c b/drivers/of/device.c
>> index 2de320d..17504f4 100644
>> --- a/drivers/of/device.c
>> +++ b/drivers/of/device.c
>> @@ -105,12 +105,19 @@ void of_dma_configure(struct device *dev, struct
>> device_node *np)
>> ret = of_dma_get_range(np, &dma_addr, &paddr, &size);
>> if (ret < 0) {
>> dma_addr = offset = 0;
>> - size = dev->coherent_dma_mask;
>> + size = dev->coherent_dma_mask + 1;
>> } else {
>> offset = PFN_DOWN(paddr - dma_addr);
>> dev_dbg(dev, "dma_pfn_offset(%#08lx)\n", offset);
>> }
>>
>> + if (is_power_of_2(size + 1))
>> + size = size + 1;
>> + else if (!is_power_of_2(size)) {
>> + dev_err(dev, "invalid size\n");
>> + return;
>> + }
>> +
>
> Couldn't these checks go into the "else" path above? We don't need to
> check the non-DT case, because we know we've just set it to something
> sensible.
Robin,

Sure it can. I was doing flip/flop on the choice and thought it doesn' 
matter either way. Please also repond to Catalin's comment if you have 
any issues so that I can avoid additional spin on this patch.

Thanks

Murali
>
> Robin.
>
>> dev->dma_pfn_offset = offset;
>>
>> coherent = of_dma_is_coherent(np);
>>
>
>


-- 
Murali Karicheri
Linux Kernel, Texas Instruments

[PATCH v5 4/8] PCI: add helper functions pci_get[put]_host_bridge_device()

[Murali Karicheri]

Add a helper function to get/put the root bus's host bridge device.

Cc: Joerg Roedel <joro-zLv9SwRftAIdnm+yROfE0A@public.gmane.org>
Cc: Grant Likely <grant.likely-QSEj5FYQhm4dnm+yROfE0A@public.gmane.org>
Cc: Rob Herring <robh+dt-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org>
Cc: Will Deacon <will.deacon-5wv7dgnIgG8@public.gmane.org>
Cc: Russell King <linux-lFZ/pmaqli7XmaaqVzeoHQ@public.gmane.org>
Cc: Arnd Bergmann <arnd-r2nGTMty4D4@public.gmane.org>
Cc: Suravee Suthikulpanit <Suravee.Suthikulpanit-5C7GfCeVMHo@public.gmane.org>

Acked-by: Bjorn Helgaas <bhelgaas-hpIqsD4AKlfQT0dZR+AlfA@public.gmane.org>
Signed-off-by: Murali Karicheri <m-karicheri2-l0cyMroinI0@public.gmane.org>
---
 drivers/pci/host-bridge.c |   14 ++++++++++++++
 include/linux/pci.h       |    3 +++
 2 files changed, 17 insertions(+)

diff --git a/drivers/pci/host-bridge.c b/drivers/pci/host-bridge.c
index 0e5f3c9..f58e05b 100644
--- a/drivers/pci/host-bridge.c
+++ b/drivers/pci/host-bridge.c
@@ -23,6 +23,20 @@ static struct pci_host_bridge *find_pci_host_bridge(struct pci_bus *bus)
 	return to_pci_host_bridge(root_bus->bridge);
 }
 
+struct device *pci_get_host_bridge_device(struct pci_dev *dev)
+{
+	struct pci_bus *root_bus = find_pci_root_bus(dev->bus);
+	struct device *bridge = root_bus->bridge;
+
+	kobject_get(&bridge->kobj);
+	return bridge;
+}
+
+void  pci_put_host_bridge_device(struct device *dev)
+{
+	kobject_put(&dev->kobj);
+}
+
 void pci_set_host_bridge_release(struct pci_host_bridge *bridge,
 				 void (*release_fn)(struct pci_host_bridge *),
 				 void *release_data)
diff --git a/include/linux/pci.h b/include/linux/pci.h
index 9603094..d677c66 100644
--- a/include/linux/pci.h
+++ b/include/linux/pci.h
@@ -513,6 +513,9 @@ static inline struct pci_dev *pci_upstream_bridge(struct pci_dev *dev)
 	return dev->bus->self;
 }
 
+struct device *pci_get_host_bridge_device(struct pci_dev *dev);
+void pci_put_host_bridge_device(struct device *dev);
+
 #ifdef CONFIG_PCI_MSI
 static inline bool pci_dev_msi_enabled(struct pci_dev *pci_dev)
 {
-- 
1.7.9.5

[PATCH v5 5/8] of/pci: add of_pci_dma_configure() update dma configuration

[Murali Karicheri]

Add of_pci_dma_configure() to allow updating the dma configuration
of the pci device using the configuration from DT of the parent of
the root bridge device. Use the newly added APIs
pci_get/put_host_bridge_device() for implementing this.

Cc: Joerg Roedel <joro-zLv9SwRftAIdnm+yROfE0A@public.gmane.org>
Cc: Grant Likely <grant.likely-QSEj5FYQhm4dnm+yROfE0A@public.gmane.org>
Cc: Rob Herring <robh+dt-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org>
Cc: Will Deacon <will.deacon-5wv7dgnIgG8@public.gmane.org>
Cc: Russell King <linux-lFZ/pmaqli7XmaaqVzeoHQ@public.gmane.org>
Cc: Arnd Bergmann <arnd-r2nGTMty4D4@public.gmane.org>
Cc: Suravee Suthikulpanit <Suravee.Suthikulpanit-5C7GfCeVMHo@public.gmane.org>

Acked-by: Bjorn Helgaas <bhelgaas-hpIqsD4AKlfQT0dZR+AlfA@public.gmane.org>
Signed-off-by: Murali Karicheri <m-karicheri2-l0cyMroinI0@public.gmane.org>
---
 drivers/of/of_pci.c    |   19 +++++++++++++++++++
 include/linux/of_pci.h |    5 +++++
 2 files changed, 24 insertions(+)

diff --git a/drivers/of/of_pci.c b/drivers/of/of_pci.c
index 88471d3..0f1dd0b 100644
--- a/drivers/of/of_pci.c
+++ b/drivers/of/of_pci.c
@@ -2,6 +2,7 @@
 #include <linux/export.h>
 #include <linux/of.h>
 #include <linux/of_address.h>
+#include <linux/of_device.h>
 #include <linux/of_pci.h>
 #include <linux/slab.h>
 
@@ -229,6 +230,24 @@ parse_failed:
 	return err;
 }
 EXPORT_SYMBOL_GPL(of_pci_get_host_bridge_resources);
+
+/**
+ * of_pci_dma_configure - Setup DMA configuration
+ * @dev: ptr to pci_dev struct of the pci device
+ *
+ * Function to update PCI devices's DMA configuration using the same
+ * info from the OF node of root host bridge's parent.
+ */
+void of_pci_dma_configure(struct pci_dev *pci_dev)
+{
+	struct device *dev = &pci_dev->dev;
+	struct device *bridge = pci_get_host_bridge_device(pci_dev);
+
+	of_dma_configure(dev, bridge->parent->of_node);
+	pci_put_host_bridge_device(bridge);
+}
+EXPORT_SYMBOL_GPL(of_pci_dma_configure);
+
 #endif /* CONFIG_OF_ADDRESS */
 
 #ifdef CONFIG_PCI_MSI
diff --git a/include/linux/of_pci.h b/include/linux/of_pci.h
index ce0e5ab..8f1741f 100644
--- a/include/linux/of_pci.h
+++ b/include/linux/of_pci.h
@@ -16,6 +16,7 @@ int of_pci_get_devfn(struct device_node *np);
 int of_irq_parse_and_map_pci(const struct pci_dev *dev, u8 slot, u8 pin);
 int of_pci_parse_bus_range(struct device_node *node, struct resource *res);
 int of_get_pci_domain_nr(struct device_node *node);
+void of_pci_dma_configure(struct pci_dev *pci_dev);
 #else
 static inline int of_irq_parse_pci(const struct pci_dev *pdev, struct of_phandle_args *out_irq)
 {
@@ -50,6 +51,10 @@ of_get_pci_domain_nr(struct device_node *node)
 {
 	return -1;
 }
+
+static inline void of_pci_dma_configure(struct pci_dev *pci_dev)
+{
+}
 #endif
 
 #if defined(CONFIG_OF_ADDRESS)
-- 
1.7.9.5

Re: [PATCH v5 5/8] of/pci: add of_pci_dma_configure() update dma configuration

[Rob Herring]

On Tue, Jan 27, 2015 at 3:00 PM, Murali Karicheri <m-karicheri2-l0cyMroinI0@public.gmane.org> wrote:
> Add of_pci_dma_configure() to allow updating the dma configuration
> of the pci device using the configuration from DT of the parent of
> the root bridge device. Use the newly added APIs
> pci_get/put_host_bridge_device() for implementing this.
>
> Cc: Joerg Roedel <joro-zLv9SwRftAIdnm+yROfE0A@public.gmane.org>
> Cc: Grant Likely <grant.likely-QSEj5FYQhm4dnm+yROfE0A@public.gmane.org>
> Cc: Rob Herring <robh+dt-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org>

Acked-by: Rob Herring <robh-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org>

> Cc: Will Deacon <will.deacon-5wv7dgnIgG8@public.gmane.org>
> Cc: Russell King <linux-lFZ/pmaqli7XmaaqVzeoHQ@public.gmane.org>
> Cc: Arnd Bergmann <arnd-r2nGTMty4D4@public.gmane.org>
> Cc: Suravee Suthikulpanit <Suravee.Suthikulpanit-5C7GfCeVMHo@public.gmane.org>
>
> Acked-by: Bjorn Helgaas <bhelgaas-hpIqsD4AKlfQT0dZR+AlfA@public.gmane.org>
> Signed-off-by: Murali Karicheri <m-karicheri2-l0cyMroinI0@public.gmane.org>
> ---
>  drivers/of/of_pci.c    |   19 +++++++++++++++++++
>  include/linux/of_pci.h |    5 +++++
>  2 files changed, 24 insertions(+)
>
> diff --git a/drivers/of/of_pci.c b/drivers/of/of_pci.c
> index 88471d3..0f1dd0b 100644
> --- a/drivers/of/of_pci.c
> +++ b/drivers/of/of_pci.c
> @@ -2,6 +2,7 @@
>  #include <linux/export.h>
>  #include <linux/of.h>
>  #include <linux/of_address.h>
> +#include <linux/of_device.h>
>  #include <linux/of_pci.h>
>  #include <linux/slab.h>
>
> @@ -229,6 +230,24 @@ parse_failed:
>         return err;
>  }
>  EXPORT_SYMBOL_GPL(of_pci_get_host_bridge_resources);
> +
> +/**
> + * of_pci_dma_configure - Setup DMA configuration
> + * @dev: ptr to pci_dev struct of the pci device
> + *
> + * Function to update PCI devices's DMA configuration using the same
> + * info from the OF node of root host bridge's parent.
> + */
> +void of_pci_dma_configure(struct pci_dev *pci_dev)
> +{
> +       struct device *dev = &pci_dev->dev;
> +       struct device *bridge = pci_get_host_bridge_device(pci_dev);
> +
> +       of_dma_configure(dev, bridge->parent->of_node);
> +       pci_put_host_bridge_device(bridge);
> +}
> +EXPORT_SYMBOL_GPL(of_pci_dma_configure);
> +
>  #endif /* CONFIG_OF_ADDRESS */
>
>  #ifdef CONFIG_PCI_MSI
> diff --git a/include/linux/of_pci.h b/include/linux/of_pci.h
> index ce0e5ab..8f1741f 100644
> --- a/include/linux/of_pci.h
> +++ b/include/linux/of_pci.h
> @@ -16,6 +16,7 @@ int of_pci_get_devfn(struct device_node *np);
>  int of_irq_parse_and_map_pci(const struct pci_dev *dev, u8 slot, u8 pin);
>  int of_pci_parse_bus_range(struct device_node *node, struct resource *res);
>  int of_get_pci_domain_nr(struct device_node *node);
> +void of_pci_dma_configure(struct pci_dev *pci_dev);
>  #else
>  static inline int of_irq_parse_pci(const struct pci_dev *pdev, struct of_phandle_args *out_irq)
>  {
> @@ -50,6 +51,10 @@ of_get_pci_domain_nr(struct device_node *node)
>  {
>         return -1;
>  }
> +
> +static inline void of_pci_dma_configure(struct pci_dev *pci_dev)
> +{
> +}
>  #endif
>
>  #if defined(CONFIG_OF_ADDRESS)
> --
> 1.7.9.5
>
--
To unsubscribe from this list: send the line "unsubscribe devicetree" in
the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html

[PATCH v5 6/8] PCI: update dma configuration from DT

[Murali Karicheri]

If there is a DT node available for the root bridge's parent device,
use the dma configuration from that device node. For example, keystone
PCI devices would require dma_pfn_offset to be set correctly in the
device structure of the pci device in order to have the correct dma mask.
The DT node will have dma-ranges defined for this. Also support using
the DT property dma-coherent to allow coherent DMA operation by the
PCI device.

This patch use the new helper function of_pci_dma_configure() to update
the device dma configuration.

Cc: Joerg Roedel <joro-zLv9SwRftAIdnm+yROfE0A@public.gmane.org>
Cc: Grant Likely <grant.likely-QSEj5FYQhm4dnm+yROfE0A@public.gmane.org>
Cc: Rob Herring <robh+dt-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org>
Cc: Will Deacon <will.deacon-5wv7dgnIgG8@public.gmane.org>
Cc: Russell King <linux-lFZ/pmaqli7XmaaqVzeoHQ@public.gmane.org>
Cc: Arnd Bergmann <arnd-r2nGTMty4D4@public.gmane.org>
Cc: Suravee Suthikulpanit <Suravee.Suthikulpanit-5C7GfCeVMHo@public.gmane.org>

Acked-by: Bjorn Helgaas <bhelgaas-hpIqsD4AKlfQT0dZR+AlfA@public.gmane.org>
Signed-off-by: Murali Karicheri <m-karicheri2-l0cyMroinI0@public.gmane.org>
---
 drivers/pci/probe.c |    2 ++
 1 file changed, 2 insertions(+)

diff --git a/drivers/pci/probe.c b/drivers/pci/probe.c
index 23212f8..d7dcd6c 100644
--- a/drivers/pci/probe.c
+++ b/drivers/pci/probe.c
@@ -6,6 +6,7 @@
 #include <linux/delay.h>
 #include <linux/init.h>
 #include <linux/pci.h>
+#include <linux/of_pci.h>
 #include <linux/pci_hotplug.h>
 #include <linux/slab.h>
 #include <linux/module.h>
@@ -1520,6 +1521,7 @@ void pci_device_add(struct pci_dev *dev, struct pci_bus *bus)
 	dev->dev.dma_mask = &dev->dma_mask;
 	dev->dev.dma_parms = &dev->dma_parms;
 	dev->dev.coherent_dma_mask = 0xffffffffull;
+	of_pci_dma_configure(dev);
 
 	pci_set_dma_max_seg_size(dev, 65536);
 	pci_set_dma_seg_boundary(dev, 0xffffffff);
-- 
1.7.9.5

[PATCH v5 7/8] arm: dma-mapping: limit iommu mapping size

[Murali Karicheri]

arm_iommu_create_mapping() has size parameter of size_t and
arm_setup_iommu_dma_ops() can take a value higher than that
when this is called from the of code. So limit the size to
SIZE_MAX.

Cc: Joerg Roedel <joro-zLv9SwRftAIdnm+yROfE0A@public.gmane.org>
Cc: Grant Likely <grant.likely-QSEj5FYQhm4dnm+yROfE0A@public.gmane.org>
Cc: Rob Herring <robh+dt-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org>
Cc: Bjorn Helgaas <bhelgaas-hpIqsD4AKlfQT0dZR+AlfA@public.gmane.org>
Cc: Will Deacon <will.deacon-5wv7dgnIgG8@public.gmane.org>
Cc: Russell King <linux-lFZ/pmaqli7XmaaqVzeoHQ@public.gmane.org>
Cc: Arnd Bergmann <arnd-r2nGTMty4D4@public.gmane.org>
Cc: Suravee Suthikulpanit <Suravee.Suthikulpanit-5C7GfCeVMHo@public.gmane.org>

Signed-off-by: Murali Karicheri <m-karicheri2-l0cyMroinI0@public.gmane.org>
---
 arch/arm/mm/dma-mapping.c |    7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/arch/arm/mm/dma-mapping.c b/arch/arm/mm/dma-mapping.c
index 7864797..496b2c3 100644
--- a/arch/arm/mm/dma-mapping.c
+++ b/arch/arm/mm/dma-mapping.c
@@ -2004,6 +2004,13 @@ static bool arm_setup_iommu_dma_ops(struct device *dev, u64 dma_base, u64 size,
 	if (!iommu)
 		return false;
 
+	/*
+	 * currently arm_iommu_create_mapping() takes a max of size_t
+	 * for size param. So check this limit for now.
+	 */
+	if (size > SIZE_MAX)
+		return false;
+
 	mapping = arm_iommu_create_mapping(dev->bus, dma_base, size);
 	if (IS_ERR(mapping)) {
 		pr_warn("Failed to create %llu-byte IOMMU mapping for device %s\n",
-- 
1.7.9.5

[PATCH v5 8/8] of: limit dma_mask of the device based on dma-range size

[Murali Karicheri]

limit the device dma_mask to the min of default dma_mask and
mask calculate from the dma-range size.

Cc: Joerg Roedel <joro-zLv9SwRftAIdnm+yROfE0A@public.gmane.org>
Cc: Grant Likely <grant.likely-QSEj5FYQhm4dnm+yROfE0A@public.gmane.org>
Cc: Rob Herring <robh+dt-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org>
Cc: Bjorn Helgaas <bhelgaas-hpIqsD4AKlfQT0dZR+AlfA@public.gmane.org>
Cc: Will Deacon <will.deacon-5wv7dgnIgG8@public.gmane.org>
Cc: Russell King <linux-lFZ/pmaqli7XmaaqVzeoHQ@public.gmane.org>
Cc: Arnd Bergmann <arnd-r2nGTMty4D4@public.gmane.org>
Cc: Suravee Suthikulpanit <Suravee.Suthikulpanit-5C7GfCeVMHo@public.gmane.org>

Signed-off-by: Murali Karicheri <m-karicheri2-l0cyMroinI0@public.gmane.org>
---
 drivers/of/device.c |    3 +++
 1 file changed, 3 insertions(+)

diff --git a/drivers/of/device.c b/drivers/of/device.c
index 17504f4..bcb8a35 100644
--- a/drivers/of/device.c
+++ b/drivers/of/device.c
@@ -128,6 +128,9 @@ void of_dma_configure(struct device *dev, struct device_node *np)
 	dev_dbg(dev, "device is%sbehind an iommu\n",
 		iommu ? " " : " not ");
 
+	/* limit dma_mask to the lower of the two values */
+	*dev->dma_mask = min((*dev->dma_mask), (dma_addr + size - 1));
+
 	arch_setup_dma_ops(dev, dma_addr, size, iommu, coherent);
 }
 EXPORT_SYMBOL_GPL(of_dma_configure);
-- 
1.7.9.5