Re: What pokes the ISA IO port of 0x211 ?

H. Peter Anvin
2008-04-21T17:43:46Z

Bart Van Assche wrote:
> On Mon, Apr 21, 2008 at 1:12 PM, Frantisek Rysanek
> <Frantisek.Rysanek@post.cz> wrote:
>> I'm dealing with an embedded PC motherboard that contains some custom
>> circuitry (GPIO), accessible via an ISA IO range between 0x200 and
>> 0x218.
>>
>> There's an interesting issue with this in recent Linux (tried
>> 2.6.22.6 and 2.6.24.2): something probes IO port 0x211 on boot, which
>> happens to be an add-on buzzer control port - effectively the kernel
>> boot launches an accoustic alarm :-)
>>
>> Any ideas what this could be?
>
> Did you already have a look at /proc/ioports ? This file should
> contain every range of ISA bus address in use by any kernel component.
>

This might not be the case if a probe fails and the driver unload
itself. It might be easiest to put in a hack in the kernel by hacking
outb/outw/outl and print stack trace when called when trying to poke
this port.

For what it's worth, this port is specified as "Game Blaster" in the
Interrupt List.

-hpa