On Mon, Sep 07, 2020 at 08:19:43PM +0200, Nicolas Saenz Julienne wrote: > Indeed, that's why I wasn't all that happy with my solution. > > As an alternative, how about returning '-dev->bus_dma_limit' instead of 0? > It's > always 0 for the devices without bus_dma_regions, and, I think, an always > unattainable offset for devices that do (I tested it on RPi4 with the 30bit > limitd mmc controller and it seems to work alright).
No, bus_dma_limit can be set independent of offsets. We use it e.g. to limit old x86 VIA PCI bridges to 32-bit addressing. _______________________________________________ iommu mailing list iommu@lists.linux-foundation.org https://lists.linuxfoundation.org/mailman/listinfo/iommu