dma-mapping: replace set_arch_dma_coherent_ops with arch_setup_dma_ops

set_arch_dma_coherent_ops is called from of_dma_configure in order to
swizzle the architectural dma-mapping functions over to a cache-coherent
implementation. This is currently implemented only for ARM.

In anticipation of re-using this mechanism for IOMMU-backed dma-mapping
ops too, this patch replaces the function with a broader
arch_setup_dma_ops callback which will be extended in future.

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>

diff --git a/arch/arm/include/asm/dma-mapping.h b/arch/arm/include/asm/dma-mapping.h
index 85738b200023a4d09243175eb023040cd50a0527..dc3420e777581437089a23a6e37635db0182f20e 100644 (file)
--- a/arch/arm/include/asm/dma-mapping.h
+++ b/arch/arm/include/asm/dma-mapping.h
@@ -121,12 +121,12 @@ static inline unsigned long dma_max_pfn(struct device *dev)
 }
 #define dma_max_pfn(dev) dma_max_pfn(dev)
 
-static inline int set_arch_dma_coherent_ops(struct device *dev)
+static inline void arch_setup_dma_ops(struct device *dev, bool coherent)
 {
-       set_dma_ops(dev, &arm_coherent_dma_ops);
-       return 0;
+       if (coherent)
+               set_dma_ops(dev, &arm_coherent_dma_ops);
 }
-#define set_arch_dma_coherent_ops(dev) set_arch_dma_coherent_ops(dev)
+#define arch_setup_dma_ops arch_setup_dma_ops
 
 static inline dma_addr_t phys_to_dma(struct device *dev, phys_addr_t paddr)
 {

diff --git a/drivers/of/platform.c b/drivers/of/platform.c
index 3b64d0bf5bba559c7e87b7da78e49ac037d78759..ff1f4e9afccb10d68d32fe2b04b5a31d4bb858e0 100644 (file)
--- a/drivers/of/platform.c
+++ b/drivers/of/platform.c
@@ -164,6 +164,8 @@ static void of_dma_configure(struct device *dev)
 {
        u64 dma_addr, paddr, size;
        int ret;
+       bool coherent;
+       unsigned long offset;
 
        /*
         * Set default dma-mask to 32 bit. Drivers are expected to setup
@@ -178,28 +180,21 @@ static void of_dma_configure(struct device *dev)
        if (!dev->dma_mask)
                dev->dma_mask = &dev->coherent_dma_mask;
 
-       /*
-        * if dma-coherent property exist, call arch hook to setup
-        * dma coherent operations.
-        */
-       if (of_dma_is_coherent(dev->of_node)) {
-               set_arch_dma_coherent_ops(dev);
-               dev_dbg(dev, "device is dma coherent\n");
-       }
-
-       /*
-        * if dma-ranges property doesn't exist - just return else
-        * setup the dma offset
-        */
        ret = of_dma_get_range(dev->of_node, &dma_addr, &paddr, &size);
        if (ret < 0) {
-               dev_dbg(dev, "no dma range information to setup\n");
-               return;
+               dma_addr = offset = 0;
+               size = dev->coherent_dma_mask;
+       } else {
+               offset = PFN_DOWN(paddr - dma_addr);
+               dev_dbg(dev, "dma_pfn_offset(%#08lx)\n", dev->dma_pfn_offset);
        }
+       dev->dma_pfn_offset = offset;
+
+       coherent = of_dma_is_coherent(dev->of_node);
+       dev_dbg(dev, "device is%sdma coherent\n",
+               coherent ? " " : " not ");
 
-       /* DMA ranges found. Calculate and set dma_pfn_offset */
-       dev->dma_pfn_offset = PFN_DOWN(paddr - dma_addr);
-       dev_dbg(dev, "dma_pfn_offset(%#08lx)\n", dev->dma_pfn_offset);
+       arch_setup_dma_ops(dev, coherent);
 }
 
 /**

diff --git a/include/linux/dma-mapping.h b/include/linux/dma-mapping.h
index d5d388160f420e86a325e1b44d8ff9f7d28b43c9..8a1560f95d4ab92636d5034aa52d2c76ecff89f7 100644 (file)
--- a/include/linux/dma-mapping.h
+++ b/include/linux/dma-mapping.h
@@ -129,11 +129,8 @@ static inline int dma_coerce_mask_and_coherent(struct device *dev, u64 mask)
 
 extern u64 dma_get_required_mask(struct device *dev);
 
-#ifndef set_arch_dma_coherent_ops
-static inline int set_arch_dma_coherent_ops(struct device *dev)
-{
-       return 0;
-}
+#ifndef arch_setup_dma_ops
+static inline void arch_setup_dma_ops(struct device *dev, bool coherent) { }
 #endif
 
 static inline unsigned int dma_get_max_seg_size(struct device *dev)