From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932162AbXLNBvV (ORCPT ); Thu, 13 Dec 2007 20:51:21 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1758147AbXLNBvN (ORCPT ); Thu, 13 Dec 2007 20:51:13 -0500 Received: from mho-02-bos.mailhop.org ([63.208.196.179]:60915 "EHLO mho-02-bos.mailhop.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752426AbXLNBvM (ORCPT ); Thu, 13 Dec 2007 20:51:12 -0500 X-Mail-Handler: MailHop Outbound by DynDNS X-Originating-IP: 216.15.117.105 X-Report-Abuse-To: abuse@dyndns.com (see http://www.mailhop.org/outbound/abuse.html for abuse reporting information) X-MHO-User: U2FsdGVkX1/E/Bl14v7EPOh4kQxD8Enu Message-ID: <4761E169.4020407@reed.com> Date: Thu, 13 Dec 2007 20:50:33 -0500 From: "David P. Reed" User-Agent: Mozilla/5.0 (X11; U; Linux x86_64; en-US; rv:1.8.1.5) Gecko/20070727 Fedora/2.0.0.5-2.fc7 Thunderbird/2.0.0.5 Mnenhy/0.7.5.0 MIME-Version: 1.0 To: Alan Cox CC: David Newall , Rene Herman , Paul Rolland , "H. Peter Anvin" , Krzysztof Halasa , Pavel Machek , Andi Kleen , linux-kernel@vger.kernel.org, Thomas Gleixner , Ingo Molnar , rol@witbe.net Subject: Re: RFC: outb 0x80 in inb_p, outb_p harmful on some modern AMD64 with MCP51 laptops References: <475879CD.9080006@reed.com> <20071207160439.71b7f46a@the-village.bc.nu> <20071209125458.GB4381@ucw.cz> <20071209165908.GA15910@one.firstfloor.org> <20071209212513.GC24284@elf.ucw.cz> <475CBDD7.5050602@keyaccess.nl> <475DE37F.20706@davidnewall.com> <475DE6F4.80702@zytor.com> <475DEB23.1000304@davidnewall.com> <20071211084059.3d03e11d@tux.DEF.witbe.net> <475E5D4B.8020101@keyaccess.nl> <475E7DC2.4060509@davidnewall.com> <475E8D91.20201@keyaccess.nl> <475E95A3.3070801@davidnewall.com> <20071211142552.2ae6ea9a@the-village.bc.nu> <47605E4B.6050904@davidnewall.com> <20071212230030.00511c3f@the-village.bc.nu> <47612FF9.8060402@reed.com> <20071213132112.66d59aa2@the-village.bc.nu> In-Reply-To: <20071213132112.66d59aa2@the-village.bc.nu> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Simulating 1 microsecond delays (assuming LPC meets that goal for 0x80) is "absolutely correct" for devices provided on PCI-X running on 3 GHz or greater machines? Well, you are entitled to your opinion. Seems likely that reading the timing specs of such a chipset might be correct, and delaying for a time proportional to CPU speed, rather than assuming running 3000 3GHz clock cycles is needed on a very fast emulation of an old device that probably runs at the fastest bus speed provided in the chipset. Every device has different timing constraints. In the real world that I live in. Alan Cox wrote: > On Thu, 13 Dec 2007 08:13:29 -0500 > "David P. Reed" wrote: > > >> Perhaps what was meant is that ISA-tuned timings make little sense on >> devices that are part of the chipset or on the PCI or PCI-X buses? >> > > No. > > ISA as LPC bus is alive and well inside and outside chipsets. Welcome to > planet earth and the reality of 'its cheaper to reuse cells than design a > new one'. For the chipset logic like DMA controllers the _p is absolutely > correct. > > Alan > >