Re: [PATCH] x86: provide a DMI based port 0x80 I/O delay override.

[Bodo Eggert]

On Mon, 7 Jan 2008, Alan Cox wrote:

> > But overclocking is not the problem for udelay, it would err to the safe 
> > side. The problem would be a BUS having < 8 MHz, and since the days of 
> > 80286, they are hard to find. IMO having an option to set the bus speed
> > for those systems should be enough.
> 
> If you get it wrong you risk data corruption. Not good, not clever, not
> appropriate. Basically the use of port 0x80 is the right thing to do for
> ISA devices and as 15 odd years of use has shown works reliably and
> solidly for ISA systems.

As long as there is no port 80 card or a similar device using it. If 
there is a port 80 card, ISA acess needing the delay does break, cause
the data corruption you fear and does cause this thread to be started.
Pest, Cholera ...

OTOH, maybe the 6-MHz-delay is the same as the 8-MHz-delay, and the kernel 
parameter is not needed.
-- 
Fun things to slip into your budget
A Romulan Cloaking device:
	The PHB won't know what it is but will be to chicken to ask
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