Re: Question about outb

Davide Rossetti (rossetti@apemaia.roma1.infn.it)
Fri, 30 May 1997 13:16:25 +0200 (MET DST)


On Tue, 27 May 1997, Andrew E. Mileski wrote:

> > The card I'm writing the driver for puts its real
> > registers out of the range accessable by a short. Here's relavent part
> > of the <cat /proc/ioports>:
> >
> > efbdc000-efbddffe: ihcp
> >
> > That REALLY is the IO space for the card's registers. Am I missing
> > something?
>
> This looks to me like a memory-mapped I/O region. The ISDN driver
> does this too, but they _know_ this is "wrong" and comment it.
> The problem being no support for requesting regions of the address
> space. This isn't a huge problem in this case, since the address
> is above the legal ix86 I/O region.

I don't know if it is a PCI board. Assuming so.
Perhaps onboard formaware does not properly initialize bit x (1 ?, I
don't remember) of the configuration space register, which asks I/O space
under 1MB to power-on bios. so it is configured somewhere in full 32bit
address space. you can always over-write it.

regards.

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