Messages in this thread | | | Date | Mon, 21 Apr 2008 13:40:08 -0400 | From | "H. Peter Anvin" <> | Subject | Re: What pokes the ISA IO port of 0x211 ? |
| |
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
| |