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RE: DMA across PCI
> I am guessing that there is no such thing as DMA in the PCI world. Is
> that the case ?
Yes there is. Master is different from DMA. A PCI 'master' is the device
that is 'initiating' the transaction on the PCI bus, and it doesn't have to
be a DMA, it can be a CPU for that matter. A DMA is what is known as a
'third party' device, it basically initiates a 'read' from one 'party', and
then a 'write' to the second 'party'. It may or may not store the data
intermediately, it depends on the architecture of the DMA.
The big difference between ISA DMA and PCI DMA is ISA had general purpose
DMA channels, and PCI DMA is specific to a particular PCI device.
I'd suggest checking out the PLX spec to get a better understanding of DMA
on the PCI bus.