Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758000AbXL3Qas (ORCPT ); Sun, 30 Dec 2007 11:30:48 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1755426AbXL3Qal (ORCPT ); Sun, 30 Dec 2007 11:30:41 -0500 Received: from smtpq2.groni1.gr.home.nl ([213.51.130.201]:37147 "EHLO smtpq2.groni1.gr.home.nl" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753426AbXL3Qak (ORCPT ); Sun, 30 Dec 2007 11:30:40 -0500 Message-ID: <4777C6E8.7060202@keyaccess.nl> Date: Sun, 30 Dec 2007 17:27:20 +0100 From: Rene Herman User-Agent: Thunderbird 2.0.0.9 (X11/20071031) MIME-Version: 1.0 To: Ingo Molnar CC: Alan Cox , Linus Torvalds , dpreed@reed.com, Islam Amer , hpa@zytor.com, Pavel Machek , Ingo Molnar , Andi Kleen , Thomas Gleixner , Linux Kernel Subject: Re: [PATCH] x86: provide a DMI based port 0x80 I/O delay override References: <477711DC.5030800@keyaccess.nl> <20071230144700.78f4605c@the-village.bc.nu> <20071230152835.GX16946@elte.hu> <4777BDA5.4050203@keyaccess.nl> <20071230160751.GB26221@elte.hu> In-Reply-To: <20071230160751.GB26221@elte.hu> Content-Type: text/plain; charset=ISO-8859-15; format=flowed Content-Transfer-Encoding: 7bit X-Spam-Score: -1.0 (-) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1571 Lines: 35 On 30-12-07 17:07, Ingo Molnar wrote: > * Rene Herman wrote: > >> On 30-12-07 16:28, Ingo Molnar wrote: >> >>> hardware. (which makes it a perfect delay register in any case) >> Hardly. Duron 1300 on AMD756: > > but that does not matter at all: that's not '90s era hardware that we > are (slightly) worried about wrt. IO delays in misc_32.c. (i.e. on > _real_ ISA systems) Real ISA systems will also generally respond faster to it than the unused port (this thing actually has an ISA bus but not VGA on it ofcourse) which means that "a perfect delay register" it is not. But yes, I have an actual Am386DX-40 with ISA VGA up and running which also doesn't care either way, about the ones in misc_32.c or anywhere else for that matter. Me myself never having seen anything actually care since using that machine actively was in fact the reason I got involved so don't get me wrong; doing away with 0x80 use would be quite sensible. It's just that various machines that _do_ need it (and which were reported to exist) are by now gathering dust in basements and will not timely respond/test this. Which, again, also means their possible regression might not be considered all that regressive but still; if x86 should support anything under the sun still it's a sensible worry. Rene. -- 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/