From owner-freebsd-hackers Fri Apr 12 21:35:35 1996 Return-Path: owner-hackers Received: (from root@localhost) by freefall.freebsd.org (8.7.3/8.7.3) id VAA17733 for hackers-outgoing; Fri, 12 Apr 1996 21:35:35 -0700 (PDT) Received: from gw.pu.ru (gw.pu.ru [193.124.85.12]) by freefall.freebsd.org (8.7.3/8.7.3) with SMTP id VAA17728 for ; Fri, 12 Apr 1996 21:35:32 -0700 (PDT) Received: from VexedVox.stud.pu.ru (root@localhost) by gw.pu.ru (8.6.10/8.6.6) with UUCP id IAA03931 for freebsd.org!hackers; Sat, 13 Apr 1996 08:39:30 +0400 Received: from lambert.org (uucp@localhost) by localhost (8.6.12/8.6.12) with UUCP id IAA02397; Sat, 13 Apr 1996 08:32:51 +0400 Received: from phaeton.artisoft.com (phaeton.Artisoft.COM [198.17.250.211]) by gw.pu.ru (8.6.10/8.6.6) with ESMTP id DAA29618; Sat, 13 Apr 1996 03:11:40 +0400 Organization: SPb State University Received: (from terry@localhost) by phaeton.artisoft.com (8.6.11/8.6.9) id QAA02748; Fri, 12 Apr 1996 16:03:55 -0700 From: Terry Lambert Message-Id: <199604122303.QAA02748@phaeton.artisoft.com> Subject: Re: DOS emulator; Silly questions ... To: root@VexedVox.stud.pu.ru (Alexey Pialkin) Date: Fri, 12 Apr 1996 16:03:54 -0700 (MST) Cc: lambert.org!terry@VexedVox.stud.pu.ru, root@VexedVox.stud.pu.ru, FreeBSD.ORG!sos@VexedVox.stud.pu.ru, atrad.adelaide.edu.au!msmith@VexedVox.stud.pu.ru, riogrande.cs.tcu.edu!tam@VexedVox.stud.pu.ru, FreeBSD.ORG!hackers@VexedVox.stud.pu.ru In-Reply-To: <199604121158.PAA00331@localhost> from "Alexey Pialkin" at Apr 12, 96 03:58:23 pm X-Mailer: ELM [version 2.4 PL24] MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: owner-hackers@FreeBSD.ORG X-Loop: FreeBSD.org Precedence: bulk > > > For what else you are going to use VM86 ? The main & sole purpose > > > of it is 8086 emulation => DOS emulation. > > > > The main purpose of VM86() in my book is BIOS driver support and > > fallback support for otherwise unsupportable hardware. > > Do you whant something like WIN95 ? :( On my mind it's not a very nice idea > to use BIOS in all cases - much better to write normal driver.... No. I just want FreeBSD to be able to run, period, on all hardware on which DOS is capable of running. I would call the drivers used to do this "fallback drivers", and they would be my *last* choice for running the system after the load process is complete. If a protected mode driver for a card exists, the kernel (by virtue of fallback drivers being in their own ELF segments) would unload the default fallback driver, as it is no longer needed, and recover the space it uses in the statically linked kernel. The result is the FreeBSD would work with all disk controllers with BIOS on board, with or without someone having written a protected mode driver for it. It would support all console video modes for CGA/EGA/VGA/PGA/XGA or SuperVGA cards via INT 10 BIOS calls. It would support interoperability with DOS partitioning because it wold be able to determine the BIOS geometry for partitioning from protected mode. It would support MCA. With a little work on support for protected mode calls to the "DOS not busy" interrupt, it could support any CDROM for which an ASPI driver was provided by the manufacturer. Yes, it's much better to have a native protected mode driver. But anything that works is better than anything that doesn't. Terry Lambert terry@lambert.org --- Any opinions in this posting are my own and not those of my present or previous employers.