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Re: IOMMU setup vs DAC (PCI)
Kanoj Sarcar writes:
> dma_addr_t should be unsigned long, which is 64 bits on 64 bit
> architectures, so things are fine there.
>
> On regular x86, dma_addr_t is u32, which still works.
It's 32-bit on sparc64 since 32-bit DMA addresses are all
we need since the IOMMU is used for anything.
In fact, if your architecture is doing nothing other
than PCI, you _OUGHT_ to make it 32-bit even on 64-bit
platforms because the PCI dma interface does not support
64-bit DACs in any way shape or form until 2.5.x in then
a new dma64_addr_t type will be used to denote a DAC
address.
Later,
David S. Miller
davem@redhat.com
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