From owner-freebsd-alpha Tue Oct 13 17:22:07 1998 Return-Path: Received: (from majordom@localhost) by hub.freebsd.org (8.8.8/8.8.8) id RAA29697 for freebsd-alpha-outgoing; Tue, 13 Oct 1998 17:22:07 -0700 (PDT) (envelope-from owner-freebsd-alpha@FreeBSD.ORG) Received: from smtp03.primenet.com (smtp03.primenet.com [206.165.6.133]) by hub.freebsd.org (8.8.8/8.8.8) with ESMTP id RAA29533 for ; Tue, 13 Oct 1998 17:21:59 -0700 (PDT) (envelope-from tlambert@usr08.primenet.com) Received: (from daemon@localhost) by smtp03.primenet.com (8.8.8/8.8.8) id RAA25196; Tue, 13 Oct 1998 17:21:45 -0700 (MST) Received: from usr08.primenet.com(206.165.6.208) via SMTP by smtp03.primenet.com, id smtpd025179; Tue Oct 13 17:21:41 1998 Received: (from tlambert@localhost) by usr08.primenet.com (8.8.5/8.8.5) id RAA19183; Tue, 13 Oct 1998 17:21:37 -0700 (MST) From: Terry Lambert Message-Id: <199810140021.RAA19183@usr08.primenet.com> Subject: Re: PALcode To: cjs@portal.ca (Curt Sampson) Date: Wed, 14 Oct 1998 00:21:36 +0000 (GMT) Cc: tlambert@primenet.com, seifert@sequent.com, alpha@FreeBSD.ORG In-Reply-To: from "Curt Sampson" at Oct 13, 98 10:36:42 am X-Mailer: ELM [version 2.4 PL25] MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: owner-freebsd-alpha@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.org > > I'm not married to ARC; I'd be just as happy with any other PALcode > > that spanned the entire product line and didn't cost extra to obtain. > > Perhaps the VMS PAL code would be a good fit.... > > Terry, I really think you should grab a copy of the _Alpha AXP > Architecture Reference Manual_ and look at the PALcode descriptions > to see what it does. I wouldn't care to make a definitive comment > one way or the other on the feasibility of something like this, > but the extent to which the PALcode you use affects your OS internal > structures and works is surprisingly large. PALcode covers not only > how you do your VM structure, but your interrupt and process > structures as well. (The actual context switch between two processes > is performed by PALcode, not OS code, for example.) Thanks, but I have copies of the relevent architecture manuals, and have read the ARC link that was poseted (by Warner?) recently, as well. I'm also familiar with the theory of writable control stores, since one of my primary fields of study was solid state physics. The point which I was trying to make is that anything that spans the entire hardware line by default is going to be a better basis for an OS that tries to span the entire hardware line than anything that doesn't. Yeah, I know that certain features make it easier to implement a UNIX-like VM system, but if you can run across all of the hardware, that's maybe more important. CGD's point about this maybe not being important really stands or falls based on what hardware is going to be commonly available, and what PLA code comes loaded. Terry Lambert terry@lambert.org --- Any opinions in this posting are my own and not those of my present or previous employers. To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-alpha" in the body of the message