From mboxrd@z Thu Jan 1 00:00:00 1970 Received: by oss.sgi.com id ; Tue, 7 Dec 1999 20:33:06 -0800 Received: from deliverator.sgi.com ([204.94.214.10]:14901 "EHLO deliverator.sgi.com") by oss.sgi.com with ESMTP id ; Tue, 7 Dec 1999 20:32:38 -0800 Received: from cthulhu.engr.sgi.com (cthulhu.engr.sgi.com [192.26.80.2]) by deliverator.sgi.com (980309.SGI.8.8.8-aspam-6.2/980310.SGI-aspam) via ESMTP id UAA02101; Tue, 7 Dec 1999 20:35:47 -0800 (PST) mail_from (owner-linux@cthulhu.engr.sgi.com) Received: (from majordomo-owner@localhost) by cthulhu.engr.sgi.com (980427.SGI.8.8.8/970903.SGI.AUTOCF) id UAA28943 for linux-list; Tue, 7 Dec 1999 20:33:07 -0800 (PST) mail_from (owner-linux@relay.engr.sgi.com) Received: from hollywood.engr.sgi.com (hollywood.engr.sgi.com [150.166.61.38]) by cthulhu.engr.sgi.com (980427.SGI.8.8.8/970903.SGI.AUTOCF) via SMTP id UAA95703 for ; Tue, 7 Dec 1999 20:33:04 -0800 (PST) mail_from (owner-linux@hollywood.engr.sgi.com) Received: from soyuz.wellington.sgi.com (soyuz.wellington.sgi.com [134.14.64.194]) by hollywood.engr.sgi.com (940816.SGI.8.6.9/960327.SGI.AUTOCF) via ESMTP id UAA24949; Tue, 7 Dec 1999 20:32:56 -0800 Received: from csd.sgi.com by soyuz.wellington.sgi.com via ESMTP (980427.SGI.8.8.8/940406.SGI) id RAA80676; Wed, 8 Dec 1999 17:30:57 +1300 (NZD) Message-ID: <384DDEF9.E3BE1F10@csd.sgi.com> Date: Wed, 08 Dec 1999 17:30:49 +1300 From: Alistair Lambie Organization: SGI X-Mailer: Mozilla 4.7 [en] (X11; I; Linux 2.2.12-20 i586) X-Accept-Language: en MIME-Version: 1.0 To: fisher@sgi.com CC: ralf@oss.sgi.com, kevink@mips.com, linux@hollywood.engr.sgi.com, William Fisher Subject: Re: Question for David Miller or anyone else about R6000 code References: <199912080313.TAA24823@hollywood.engr.sgi.com> Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Sender: owner-linuxmips@oss.sgi.com Precedence: bulk Return-Path: X-Orcpt: rfc822;linuxmips-outgoing William Fisher wrote: > > > > > On Mon, Dec 06, 1999 at 10:58:10AM +0100, Kevin D. Kissell wrote: > > > > > I'm working on cleaning up and enhancing the > > > MIPS/Linux code to support the new families > > > of CPUs coming out of MIPS Technologies Inc. > > > In doing so, I've come across and fixed a number > > > of bugs, most of which I've also passed back to > > > Ralf Baechle for integration with the moving > > > target at linux.sgi.com. But I came across > > > something this morning that, while not a problem > > > for us, puzzles me. In arch/mips/mm/r6000.c, > > > which has your name on it, there is a compiler > > > directive to use MIPS III instructions, and the > > > resulting code does indeed end up containing > > > 64-bit (daddiu, etc.) instructions. I've never > > > actually programmed an R6000, but all of the > > > information I have on that processor indicates > > > that it is a MIPS II, 32-bit design, and that those > > > instructions should therefore cause exceptions. > > > > > > Am I mistaken, or is that directive a bug? > > > > It obviously is. The R6000 code isn't supposed to work and given that > > currently none of the Linux/MIPS hackers has a) R6000 documentation and > > b) an R6000 machine an R6000 port ever happening is highly unprobable. > > As the result of this I think I'm going to just burry the R6000 support > > and while I'm at it also the R8000. > > > > Ralf > > > Since the R6000 was an ECL machine produced in late 1992, just > before the MIPS/SGI merger. There were only a few machines sold > and the machine was designed to be a Fortran FP specialist. > > Hence the R6000 is long since dead. We still have the MIPS risc/os 5.01 > operating system source code, so if anybody has lots of free cycles > to waste, I'm sure we can send them locore. > Don't forget CDC used the R6000 and ramped it to 90MHz. They also got it going in an SMP configuration with 4 processors from what I can remember. I guess it is possible that someone could actually want to burn some cycles on this, although they had better have a cheap source of power and good airconditioning :-) Alistair -- Alistair Lambie alambie@csd.sgi.com SGI Global Product Support Level 5, Cigna House, M/S: INZ-3780 PO Box 24 093, Ph: +64-4-494 6325 40 Mercer St, Wellington, Fax: +64-4-494 6321 New Zealand Mobile: +64-21-635 262