arm64: introduce is_device_dma_coherent

Introduce a boolean flag and an accessor function to check whether a
device is dma_coherent. Set the flag from set_arch_dma_coherent_ops.

Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>

diff --git a/arch/arm64/include/asm/device.h b/arch/arm64/include/asm/device.h
index cf98b36..243ef25 100644 (file)
--- a/arch/arm64/include/asm/device.h
+++ b/arch/arm64/include/asm/device.h
@@ -21,6 +21,7 @@ struct dev_archdata {
 #ifdef CONFIG_IOMMU_API
        void *iommu;                    /* private IOMMU data */
 #endif
+       bool dma_coherent;
 };
 
 struct pdev_archdata {

diff --git a/arch/arm64/include/asm/dma-mapping.h b/arch/arm64/include/asm/dma-mapping.h
index adeae3f..d34189b 100644 (file)
--- a/arch/arm64/include/asm/dma-mapping.h
+++ b/arch/arm64/include/asm/dma-mapping.h
@@ -54,11 +54,18 @@ static inline void set_dma_ops(struct device *dev, struct dma_map_ops *ops)
 
 static inline int set_arch_dma_coherent_ops(struct device *dev)
 {
+       dev->archdata.dma_coherent = true;
        set_dma_ops(dev, &coherent_swiotlb_dma_ops);
        return 0;
 }
 #define set_arch_dma_coherent_ops      set_arch_dma_coherent_ops
 
+/* do not use this function in a driver */
+static inline bool is_device_dma_coherent(struct device *dev)
+{
+       return dev->archdata.dma_coherent;
+}
+
 #include <asm-generic/dma-mapping-common.h>
 
 static inline dma_addr_t phys_to_dma(struct device *dev, phys_addr_t paddr)