public inbox for linux-kernel@vger.kernel.org
 help / color / mirror / Atom feed
From: Giacomo Catenazzi <cate@student.ethz.ch>
To: "H. Peter Anvin" <hpa@transmeta.com>
Cc: Linus Torvalds <torvalds@transmeta.com>,
	Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
	Alan Cox <alan@redhat.com>
Subject: Re: That horrible hack from hell called A20
Date: Wed, 06 Dec 2000 13:43:08 +0100	[thread overview]
Message-ID: <3A2E345C.EE6F5640@student.ethz.ch> (raw)
In-Reply-To: <fa.mnh2nkv.1kkusq6@ifi.uio.no> <fa.enh20bv.1pkea3o@ifi.uio.no>

"H. Peter Anvin" wrote:
> 
> 
> Good question.  The whole thing makes me nervous... in fact, perhaps we
> should really consider using the BIOS INT 15h interrupt to enter
> protected mode?
> 

Maybe it is better to try with INT15 AX=2400 (Enable A20 gate). 

INT 15-2400 enable A20
INT 15-2401 disable A20
INT 15-2402 query status A20
INT 15-2403 query A20 support (kdb or port 92)

IBM classifies these functions as optional, but it is enabled on a lot
of
new BIOS, no know conflicts, thus we can call this function to enable
A20,
check the result and only after failure we can try the old methods.


	giacomo
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
Please read the FAQ at http://www.tux.org/lkml/

       reply	other threads:[~2000-12-06 13:13 UTC|newest]

Thread overview: 20+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
     [not found] <fa.mnh2nkv.1kkusq6@ifi.uio.no>
     [not found] ` <fa.enh20bv.1pkea3o@ifi.uio.no>
2000-12-06 12:43   ` Giacomo Catenazzi [this message]
2000-12-06 13:01     ` That horrible hack from hell called A20 Alan Cox
2000-12-06 17:37       ` H. Peter Anvin
2000-12-05 23:30 H. Peter Anvin
2000-12-06  0:13 ` Linus Torvalds
2000-12-06  0:15   ` H. Peter Anvin
2000-12-06  1:26     ` Alan Cox
2000-12-06  0:21 ` Kai Germaschewski
2000-12-06  0:48   ` Linus Torvalds
2000-12-06 15:53     ` Richard B. Johnson
2000-12-06 18:26       ` H. Peter Anvin
2000-12-06  1:07   ` Linus Torvalds
2000-12-06  1:10     ` H. Peter Anvin
2000-12-06  1:37       ` Linus Torvalds
2000-12-06  1:41         ` Linus Torvalds
2000-12-06  2:38           ` H. Peter Anvin
2000-12-08 10:33       ` Riley Williams
2000-12-06 10:16     ` Kai Germaschewski
2000-12-06  1:25 ` Alan Cox
2000-12-06  2:05   ` H. Peter Anvin

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=3A2E345C.EE6F5640@student.ethz.ch \
    --to=cate@student.ethz.ch \
    --cc=alan@redhat.com \
    --cc=hpa@transmeta.com \
    --cc=linux-kernel@vger.kernel.org \
    --cc=torvalds@transmeta.com \
    /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