From cd15b048445d0a54f7147c35a86c5a16ef231554 Mon Sep 17 00:00:00 2001 From: Benjamin Herrenschmidt Date: Tue, 11 Feb 2014 11:32:38 +1100 Subject: powerpc/powernv: Add iommu DMA bypass support for IODA2 This patch adds the support for to create a direct iommu "bypass" window on IODA2 bridges (such as Power8) allowing to bypass iommu page translation completely for 64-bit DMA capable devices, thus significantly improving DMA performances. Additionally, this adds a hook to the struct iommu_table so that the IOMMU API / VFIO can disable the bypass when external ownership is requested, since in that case, the device will be used by an environment such as userspace or a KVM guest which must not be allowed to bypass translations. Signed-off-by: Benjamin Herrenschmidt --- arch/powerpc/include/asm/dma-mapping.h | 1 + 1 file changed, 1 insertion(+) (limited to 'arch/powerpc/include/asm/dma-mapping.h') diff --git a/arch/powerpc/include/asm/dma-mapping.h b/arch/powerpc/include/asm/dma-mapping.h index e27e9ad6818..150866b2a3f 100644 --- a/arch/powerpc/include/asm/dma-mapping.h +++ b/arch/powerpc/include/asm/dma-mapping.h @@ -134,6 +134,7 @@ static inline int dma_supported(struct device *dev, u64 mask) } extern int dma_set_mask(struct device *dev, u64 dma_mask); +extern int __dma_set_mask(struct device *dev, u64 dma_mask); #define dma_alloc_coherent(d,s,h,f) dma_alloc_attrs(d,s,h,f,NULL) -- cgit v1.2.3-70-g09d2