From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id ; Wed, 10 Jan 2001 21:00:15 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id ; Wed, 10 Jan 2001 21:00:05 -0500 Received: from neon-gw.transmeta.com ([209.10.217.66]:58118 "EHLO neon-gw.transmeta.com") by vger.kernel.org with ESMTP id ; Wed, 10 Jan 2001 20:59:52 -0500 Message-ID: <3A5D1392.281E2A83@transmeta.com> Date: Wed, 10 Jan 2001 17:59:46 -0800 From: "H. Peter Anvin" Organization: Transmeta Corporation X-Mailer: Mozilla 4.76 [en] (X11; U; Linux 2.4.0 i686) X-Accept-Language: en, sv, no, da, es, fr, ja MIME-Version: 1.0 To: "Dunlap, Randy" CC: linux-kernel@vger.kernel.org Subject: Re: The latest instance in the A20 farce In-Reply-To: Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org "Dunlap, Randy" wrote: > > I'm not sure about this, but I'm wondering if the > Fixed (as in Static) ACPI Description Table (FADT) > can indicate that the platform is a legacy-free system. > Parsing ACPI is a nightmare on steroids. That is just Not An Option[TM] in a < 10K bootstrap routine. > > > Worse, they define that port 92h, bit 1, is no longer > > A20M#... but they > > don't forbid the system from using it for other things. > > I don't quite see it that way. Where do you see that? > Maybe it just needs to be more explicit. > It probably was *intended*, but it isn't *specified*, and in fact some manufacturers have been known to abuse this bit. > Ch. 3 (SYS-0047) says that port 92h:bit 1 doesn't toggle/affect A20M#. > Appendix A says that port 92h is (still?) "System Control Port A" > (not defined here AFAIK). > (I haven't checked all of the other chapters/appendices.) > -- at work, in private! "Unix gives you enough rope to shoot yourself in the foot." http://www.zytor.com/~hpa/puzzle.txt - 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/