From owner-freebsd-alpha Wed May 8 11:16:45 2002 Delivered-To: freebsd-alpha@freebsd.org Received: from gull.prod.itd.earthlink.net (gull.mail.pas.earthlink.net [207.217.120.84]) by hub.freebsd.org (Postfix) with ESMTP id CFB4637B405; Wed, 8 May 2002 11:16:40 -0700 (PDT) Received: from pool0365.cvx21-bradley.dialup.earthlink.net ([209.179.193.110] helo=mindspring.com) by gull.prod.itd.earthlink.net with esmtp (Exim 3.33 #2) id 175VzO-0004iG-00; Wed, 08 May 2002 11:16:34 -0700 Message-ID: <3CD96B64.C9972706@mindspring.com> Date: Wed, 08 May 2002 11:16:04 -0700 From: Terry Lambert X-Mailer: Mozilla 4.7 [en]C-CCK-MCD {Sony} (Win98; U) X-Accept-Language: en MIME-Version: 1.0 To: John Baldwin Cc: freebsd-alpha@FreeBSD.ORG, Mark Santcroos , David O'Brien , Wilko Bulte Subject: Re: *bsd on srm-less alpha's References: Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Sender: owner-freebsd-alpha@FreeBSD.ORG Precedence: bulk List-ID: List-Archive: (Web Archive) List-Help: (List Instructions) List-Subscribe: List-Unsubscribe: X-Loop: FreeBSD.org John Baldwin wrote: > > Particularly in the VM system. With different microcode, you > > get digfferent machine instructions. FreeBSD relies on a > > number of instructions which act a particular way because they > > are implemented in the SRM that way. > > Umm, we use instructions from PALcode, not from SRM. Now I think SRM > contains certain versions of PALcode (VMS and Unix ones) whereas the > ARC stuff uses the NT PALcode. You would need to change more than VM > though. PAL is used for context switching and for enable/disable > interrupts, etc. Yes, of course. The VM system is (IMO) much harder to handle; the context switch can pretty much be treated as a black box, unless you try to be clever with lazy state switching. I made the mistake a while ago of trying to do this with the NT code (in fact, it was when I lived in Tucson, and could go down and talk to the Linux Alpha guys at the University there; late 1990's). While it would be nice to be able to run on all hardware because we were PAL code agnostic, it'll be quite a task, I think. That's not to discourage the effort; it's more to let anyone attempting the work know what it is they are getting into. I'm sure everyone who can will help, where possible (ambitious projects are always crowd-pleasers 8-)). -- Terry To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-alpha" in the body of the message