Displaying 5 results from an estimated 5 matches for "set_dma_offset".
2018 Aug 08
0
[RFC 0/4] Virtio uses DMA API for all devices
...pt of a
> bus address that is different. I suppose it's an ARMism to have DMA
> offsets that are separate from iommus ?
No, a lot of platforms support a bus address that has an offset from
the physical address. including a lot of power platforms:
arch/powerpc/kernel/pci-common.c: set_dma_offset(&dev->dev, PCI_DRAM_OFFSET);
arch/powerpc/platforms/cell/iommu.c: set_dma_offset(dev, cell_dma_nommu_offset);
arch/powerpc/platforms/cell/iommu.c: set_dma_offset(dev, addr);
arch/powerpc/platforms/powernv/pci-ioda.c: set_dma_offset(&pdev->dev, pe->tce_byp...
2018 Aug 08
2
[RFC 0/4] Virtio uses DMA API for all devices
On Tue, 2018-08-07 at 23:31 -0700, Christoph Hellwig wrote:
>
> You don't need to set them the time you go secure. You just need to
> set the flag from the beginning on any VM you might want to go secure.
> Or for simplicity just any VM - if the DT/ACPI tables exposed by
> qemu are good enough that will always exclude a iommu and not set a
> DMA offset, so nothing will
2018 Aug 08
2
[RFC 0/4] Virtio uses DMA API for all devices
On Tue, 2018-08-07 at 23:31 -0700, Christoph Hellwig wrote:
>
> You don't need to set them the time you go secure. You just need to
> set the flag from the beginning on any VM you might want to go secure.
> Or for simplicity just any VM - if the DT/ACPI tables exposed by
> qemu are good enough that will always exclude a iommu and not set a
> DMA offset, so nothing will
2018 Aug 08
2
[RFC 0/4] Virtio uses DMA API for all devices
...fiured with very large pages and a fixed mapping.
powernv has a separate physical window that can be configured as a real
bypass though, so does the U4 DART. Not sure about the FSL one.
But yeah, your point stands, this is just implementation details.
> arch/powerpc/kernel/pci-common.c: set_dma_offset(&dev->dev, PCI_DRAM_OFFSET);
> arch/powerpc/platforms/cell/iommu.c: set_dma_offset(dev, cell_dma_nommu_offset);
> arch/powerpc/platforms/cell/iommu.c: set_dma_offset(dev, addr);
> arch/powerpc/platforms/powernv/pci-ioda.c: set_dma_offset(&pdev->dev,...
2018 Aug 08
2
[RFC 0/4] Virtio uses DMA API for all devices
...fiured with very large pages and a fixed mapping.
powernv has a separate physical window that can be configured as a real
bypass though, so does the U4 DART. Not sure about the FSL one.
But yeah, your point stands, this is just implementation details.
> arch/powerpc/kernel/pci-common.c: set_dma_offset(&dev->dev, PCI_DRAM_OFFSET);
> arch/powerpc/platforms/cell/iommu.c: set_dma_offset(dev, cell_dma_nommu_offset);
> arch/powerpc/platforms/cell/iommu.c: set_dma_offset(dev, addr);
> arch/powerpc/platforms/powernv/pci-ioda.c: set_dma_offset(&pdev->dev,...