public inbox for linux-kernel@vger.kernel.org
 help / color / mirror / Atom feed
From: "H. Peter Anvin" <hpa@zytor.com>
To: Bart Van Assche <bart.vanassche@gmail.com>
Cc: Frantisek Rysanek <Frantisek.Rysanek@post.cz>,
	linux-kernel@vger.kernel.org
Subject: Re: What pokes the ISA IO port of 0x211 ?
Date: Mon, 21 Apr 2008 13:40:08 -0400	[thread overview]
Message-ID: <480CD178.2070806@zytor.com> (raw)
In-Reply-To: <e2e108260804210851j5cd86901r37f65190fac8a024@mail.gmail.com>

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



  reply	other threads:[~2008-04-21 17:43 UTC|newest]

Thread overview: 7+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2008-04-21 11:12 What pokes the ISA IO port of 0x211 ? Frantisek Rysanek
2008-04-21 15:51 ` Bart Van Assche
2008-04-21 17:40   ` H. Peter Anvin [this message]
2008-04-21 20:05 ` Rene Herman
2008-04-21 20:34   ` Rene Herman
2008-04-23 12:19     ` Frantisek Rysanek
2008-04-23 13:56       ` Rene Herman

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=480CD178.2070806@zytor.com \
    --to=hpa@zytor.com \
    --cc=Frantisek.Rysanek@post.cz \
    --cc=bart.vanassche@gmail.com \
    --cc=linux-kernel@vger.kernel.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox