Subject: Re: How about to config Hayes ESP with glue device rather than magical option?
To: Jason Thorpe <thorpej@nas.nasa.gov>
From: Chris G. Demetriou <cgd@pa.dec.com>
List: current-users
Date: 09/08/1997 09:35:22
> On 08 Sep 1997 08:08:02 +0900
> enami tsugutomo <enami@but-b.or.jp> wrote:
>
> > isa0 at pcib0
> > hayesesp0 at isa0 port 0x280-0x287 irq 5
> > com3 at hayesesp0 port 0x3e8-0x3f0: 1024 byte fifo
>
> Actually.... I don't understand why we have "hayesesp0 at 0x280", and
> then "come3 at hayesesp0 at 0x3e8". Why the 0x3e8? What does that
> _mean_?
I don't know what it means, but it's wrong. 8-) you should be able
to specify multiple I/O space (and other) addresses for a single ISA
device. "hayesesp" doesn't provide an ISA bus, so the hierarchy above
is ... not really sensible.
While i'm at it, it really should be just:
hayesesp0 at isa0 port ....
I.e. no 'com' at all. ("All this and more could be yours, if the
16x50 driver were ever made into a 'real' front-end/back-end -split
driver!")
> > (1) `com at isa' disables FIFO when system shutdown, but `com at
> > multi' doesn't. For Hayes ESP, it did since it was same as `com at
> > isa', but is it actually needed? In my case, it works without it but
> > since the comment says that it depends on BIOS, I can't say it is
> > unnecessary. Then, why it doesn't need for multi-port card? Does it
> > need for on board one?
>
> ...this might be a work-around for buggy super-i/o chips? If it doesn't
> hurt in the general case, why not just always disable the FIFO?
I seem to recall that this was so that losing BIOSes would recognized
the ports on reboot (!!!).
cgd