Re: IO delay, port 0x80, and BIOS POST codes

[Andi Kleen]

On Fri, Mar 15, 2002 at 01:47:39PM +0100, Martin Wilck wrote:
> On 15 Mar 2002, Andi Kleen wrote:
> 
> > > It doesn't even have to be a config option - a line
> > >
> > > /* Port used for dummy writes for I/O delays */
> > > /* Change this only if you know what you're doing ! */
> > > #define DUMMY_IO_PORT 0x80
> > >
> > > in a header file would perfectly suffice.
> >
> > That effectively already exists. You just need to change the __SLOW_DOWN_IO
> > macro in include/asm-i387/io.h
> 
> No, that doesn't cover all accesses to port 80. I am still searching.

It should. I would consider all other accesses a bug.
It is possible that some driver used it for private debugging and left it in by 
mistake. These should be removed.

-Andi