Re: inw/outw performance

Jonathan Lundell (linux@lundell-bros.com)
Sun, 30 Mar 2003 12:32:06 -0800

At 7:23pm +0200 3/30/03, Pavel Machek wrote:
> > And actually what I have found that on my development P3/1GHz system
>> every inw() takes more that 3us. I wasn't measuring outw() yet - but
>> I do not expect its timing to be better.
>
>inw/outw *is* slow. Memory map your
>registers to speed it up.

Shouldn't be *that* slow, though, especially over PCI, unless the
device in question is taking that long to respond--in which case
memory mapping won't help.

-- 
/Jonathan Lundell.
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