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SubjectRe: Specifying properly the PCI driver model on all linux archite
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> It also totally destroys Alan Cox's and other peoples statements in the past
> about Linux being faster than something like UDI because it doesn't have to
> go through a routine just to access the bus.

It would if it was some kind of klunky mapping. On a sane machine it isnt.
On x86 for example:

#define __io_virt(x) ((void *)(x))
#define memcpy_fromio(a,b,c) memcpy((a),__io_virt(b),(c))

so you get no overhead.

What happens on a sparc64 is another guess.

> It is no surprise to me that many of the drivers don't do things correctly,
> considering how tough it is to determine what correct is.

You are welcome and encouraged to submit documentation fixes. Bad documentation
is a bug.

Alan


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