Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S262136AbUCVRMQ (ORCPT ); Mon, 22 Mar 2004 12:12:16 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S262138AbUCVRMQ (ORCPT ); Mon, 22 Mar 2004 12:12:16 -0500 Received: from chaos.analogic.com ([204.178.40.224]:48258 "EHLO chaos.analogic.com") by vger.kernel.org with ESMTP id S262136AbUCVRMM (ORCPT ); Mon, 22 Mar 2004 12:12:12 -0500 Date: Mon, 22 Mar 2004 12:14:22 -0500 (EST) From: "Richard B. Johnson" X-X-Sender: root@chaos Reply-To: root@chaos.analogic.com To: Timothy Miller cc: Tigran Aivazian , David Schwartz , Justin Piszcz , Linux kernel Subject: Re: Linux Kernel Microcode Question In-Reply-To: <405F19A3.20001@techsource.com> Message-ID: References: <405F0B8D.8040408@techsource.com> <405F19A3.20001@techsource.com> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1334 Lines: 41 On Mon, 22 Mar 2004, Timothy Miller wrote: > > > Richard B. Johnson wrote: > > > > > ALL instructions are performed by the microcode. > > The Z80 had no microcode. It was completely hard-wired. > Who was talking about the Z80? The WCS was added to the Pentium line after the Patent issues were resolved. Search on "writable control store" to see the many papers and developments. > As I understand it, it's pretty much an ancient idea to do "everything" > by microcode. Only certain very complex instructions are done by microcode. > One of the "latest and greatest" such machines was made by Transmeta (a.k.a. Linus` home when he first came to the US. The Crusoe, etc., could emulate just about anything because its microcode was deliberately replaceable with even microcode that was architecturally different. > On the other hand, as I said before, it's not unreasonable for lookup > tables to be involved in instruction decoding. > Cheers, Dick Johnson Penguin : Linux version 2.4.24 on an i686 machine (797.90 BogoMips). Note 96.31% of all statistics are fiction. - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/