Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1423055AbWJGCU5 (ORCPT ); Fri, 6 Oct 2006 22:20:57 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1423057AbWJGCU5 (ORCPT ); Fri, 6 Oct 2006 22:20:57 -0400 Received: from smtp.osdl.org ([65.172.181.4]:59066 "EHLO smtp.osdl.org") by vger.kernel.org with ESMTP id S1423055AbWJGCU4 (ORCPT ); Fri, 6 Oct 2006 22:20:56 -0400 Date: Fri, 6 Oct 2006 19:20:29 -0700 (PDT) From: Linus Torvalds To: "Duran, Leo" cc: "Rafael J. Wysocki" , Arjan van de Ven , Jeff Garzik , Andi Kleen , discuss@x86-64.org, linux-kernel@vger.kernel.org Subject: RE: [discuss] Re: Please pull x86-64 bug fixes In-Reply-To: <1449F58C868D8D4E9C72945771150BDF46F8FD@SAUSEXMB1.amd.com> Message-ID: References: <1449F58C868D8D4E9C72945771150BDF46F8FD@SAUSEXMB1.amd.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: 1784 Lines: 50 On Fri, 6 Oct 2006, Duran, Leo wrote: > > So, one can argue that there's merit on having ACPI Not really. The thing is, you have two choices: - define interfaces in hardware - not doing so, and then trying to paper it over with idiotic tables. Sadly, Intel decided that they should do the latter, and invented ACPI. If instead they had decided to just let the hardware describe itself, we wouldn't need ACPI. There are two kinds of interfaces: the simple ones, and the broken ones. The simple ones are better defined by the hardware people, and they work. They are of the kind: "The pointer to the MMIO config area is readable from IO port at offset cf4h" The broken ones are the ones where hardware people know what they want to do, but they think the interface is sucky and complicated, so they make it _doubly_ sucky by then saying "we'll describe it in the BIOS tables", so that now there is another (incompetent) group that can _also_ screw things up. Yeehaa! The thing is, Intel did really well for _years_ with just defining hardware interfaces. The PIIX IDE controller interfaces were a great success, and worked for over a decade. So here's a question for you: "After having done something successfully for a decade, what do you do? Do you (a) Try to emulate a known successful strategy? (b) Put a committee together to try to come up with a new and more 'generic' solution, since you were only successful for closer to fifteen years." Guess which one is ACPI. Linus - 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/