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In a virtualized system the hypervisor may assign > non-consecutive stream IDs, or a scattered channel mask. That would > require multiple entries. > > I will document this in the description. Please let me know if it sounds > good or if you have any suggestions. Even in the non-virtualised case we can set dma-channel-mask property and only enable specific channels. Given that the hardware allows this flexibility and we could potentially have various different permutations. So I think that we need to have a flexible number of items for iommu-map. And yes, let's describe that clearer in the commit message. Jon -- nvpublic