dma-mapping: detect and configure IOMMU in of_dma_configure

This patch extends of_dma_configure so that it sets up the IOMMU for a
device, as well as the coherent/non-coherent DMA mapping ops.

Acked-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Marek Szyprowski <m.szyprowski@samsung.com>
Tested-by: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>

1 files changed, 14 insertions, 7 deletions

diff --git a/drivers/of/platform.c b/drivers/of/platform.c
index ff1f4e9afccb..b89caf8c7586 100644
--- a/drivers/of/platform.c
+++ b/drivers/of/platform.c
@@ -19,6 +19,7 @@
 #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>
@@ -166,6 +167,7 @@ static void of_dma_configure(struct device *dev)
         int ret;
         bool coherent;
         unsigned long offset;
+        struct iommu_ops *iommu;
 
         /*
          * Set default dma-mask to 32 bit. Drivers are expected to setup
@@ -194,7 +196,16 @@ static void of_dma_configure(struct device *dev)
         dev_dbg(dev, "device is%sdma coherent\n",
                 coherent ? " " : " not ");
 
-        arch_setup_dma_ops(dev, coherent);
+        iommu = of_iommu_configure(dev);
+        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);
 }
 
 /**
@@ -223,16 +234,12 @@ static struct platform_device *of_platform_device_create_pdata(
         if (!dev)
                 goto err_clear_flag;
 
-        of_dma_configure(&dev->dev);
         dev->dev.bus = &platform_bus_type;
         dev->dev.platform_data = platform_data;
-
-        /* We do not fill the DMA ops for platform devices by default.
-         * This is currently the responsibility of the platform code
-         * to do such, possibly using a device notifier
-         */
+        of_dma_configure(&dev->dev);
 
         if (of_device_add(dev) != 0) {
+                of_dma_deconfigure(&dev->dev);
                 platform_device_put(dev);
                 goto err_clear_flag;
         }