Messages in this thread | | | Date | Wed, 13 Oct 2010 10:52:41 -0400 | From | Casey Dahlin <> | Subject | A question about ZONE_DMA |
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Hi all,
So if I understand correctly, ZONE_DMA exists to separate and preserve the chunk of memory to which older ISA cards are capable of doing DMA. The question that arises for me is:
1) Why do /all/ 32-bit boxes have a ZONE_DMA when surely only a tiny and shrinking number of them have a need for it?
2) Why do /any/ 64-bit boxes have a ZONE_DMA? Is there really some godless monster out there who put an early ISA bridge and a 64-bit CPU on the same motherboard?!
Can someone shed light on what I'm missing?
--CJD
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