Stephen Warren <swarren@xxxxxxxxxxxxx> wrote @ Wed, 30 Oct 2013 23:15:00 +0100: > On 10/18/2013 04:26 AM, Hiroshi Doyu wrote: > > SMMU expects ARM_DMA_USE_IOMMU to be enabled to use DMA mapping API by > > default. > > Is the select required for the driver to be useful at all (in which case > it's fine), or simply for things to work "better" (define "better"), in > which case perhaps leaving it optional is more correct. Practically DMA API is the only interface for IOMMU(ARM_DMA_USE_IOMMU) for us, but technically they are/should be independent. SMMU driver attaches a device to some specific "map" out of multiple maps. "map" is the concept from DMA API. Attaching a device to a specific "map" belongs to "policy", which board files used to deal with. But I couldn't find any good place to do this now. Any idea? -- To unsubscribe from this list: send the line "unsubscribe linux-tegra" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
