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If it is, means usually items are distinctive, so >> I would expect defining/listing them. If they are not distinctive, >> commit msg is incorrect. If the list is as simple as 1-to-1 channel >> mapping, just add it in the description how they are ordered. > > Yes, it is a 1-to-1 channel mapping to an IOMMU ID. The intent of making > it flexible is to allow non-consecutive IOMMU ID assignments as well. > This is particularly needed in virtualised environments where the > hypervisor may reserve certain stream IDs, and the guest VM can map only > the permitted ones. Shall I add a description here mentioning this > use-case? Isn't this already handled by the 'dma-channel-mask' property? The driver will skip over any channels that are not in specified by the mask. Jon -- nvpublic