[Linaro-mm-sig] [PATCH 1/2] ARM: initial proof-of-concept IOMMU mapper for DMA-mapping

[Krishna Reddy]

Marek,

>It looks that You have simplified arm_iommu_map_sg() function too much. 
>The main advantage of the iommu is to map scattered memory pages into 
>contiguous dma address space. DMA-mapping is allowed to merge consecutive
>entries in the scatter list if hardware supports that.
>http://article.gmane.org/gmane.linux.kernel/1128416

I would update arm_iommu_map_sg() back to coalesce the sg list.

>I'm not sure if mmc drivers are aware of coalescing the SG entries together.
>If not the code must be updated to use dma_sg_len() and the dma entries
>number returned from dma_map_sg() call.

MMC drivers seem to be aware of coalescing the SG entries together as they are using dma_sg_len().

Let me test and update the patch.

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