Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755397AbYAHMyT (ORCPT ); Tue, 8 Jan 2008 07:54:19 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751411AbYAHMyF (ORCPT ); Tue, 8 Jan 2008 07:54:05 -0500 Received: from moutng.kundenserver.de ([212.227.126.186]:53722 "EHLO moutng.kundenserver.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751376AbYAHMyC (ORCPT ); Tue, 8 Jan 2008 07:54:02 -0500 Date: Tue, 8 Jan 2008 13:51:47 +0100 (CET) From: Bodo Eggert <7eggert@gmx.de> To: Rene Herman cc: "H. Peter Anvin" , Bodo Eggert <7eggert@gmx.de>, Christer Weinigel , Ingo Molnar , Alan Cox , "David P. Reed" , Paul Rolland , Pavel Machek , Thomas Gleixner , linux-kernel@vger.kernel.org, Ingo Molnar , rol@witbe.net Subject: Re: [PATCH] x86: provide a DMI based port 0x80 I/O delay override. In-Reply-To: <4782B515.3010008@keyaccess.nl> Message-ID: References: <9BdU5-1YW-9@gated-at.bofh.it> <9BeZN-3Gf-5@gated-at.bofh.it> <9BnTB-1As-31@gated-at.bofh.it> <9BrX4-8go-1@gated-at.bofh.it> <9BuBG-4eR-51@gated-at.bofh.it> <9BvRd-6aL-71@gated-at.bofh.it> <9GRQW-1DX-13@gated-at.bofh.it> <9GSah-23W-1@gated-at.bofh.it> <9GSDy-2GD-23@gated-at.bofh.it> <9GTpK-40d-15@gated-at.bofh.it> <9GUvy-5H2-11@gated-at.bofh.it> <9GVKU-7SS-25@gated-at.bofh.it> <478281A6.1000704@zytor.com> <4782A355.1070207@zytor.com> <4782AED5.1060406@keyaccess.nl> <4782B4B9.2020608@zytor.com> <4782B515.3010008@keyaccess.nl> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=us-ascii X-be10.7eggert.dyndns.org-MailScanner-Information: See www.mailscanner.info for information X-be10.7eggert.dyndns.org-MailScanner: Found to be clean X-be10.7eggert.dyndns.org-MailScanner-From: 7eggert@gmx.de X-Provags-ID: V01U2FsdGVkX18Bmq5bbi/OawHOUp1G3/27HX7BfTzP8GUGVRd En64nALV5M0Pd5Ga9lViRwMH5YP+9GLAKi2ROgHfgpD1593OEM rbKQbTSPODfEEedSTcaeg== Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1454 Lines: 33 On Tue, 8 Jan 2008, Rene Herman wrote: > On 08-01-08 00:24, H. Peter Anvin wrote: > > Rene Herman wrote: > > > Is this only about the ones then left for things like legacy PIC and PIT? > > > Does anyone care about just sticking in a udelay(2) (or 1) there as a > > > replacement and call it a day? > > > > > > > PIT is problematic because the PIT may be necessary for udelay setup. > > Yes, can initialise loops_per_jiffy conservatively. Just didn't quite get why > you guys are talking about an ISA bus speed parameter. If the ISA bus is below 8 MHz, we might need a longer delay. If we default to the longer delay, the delay will be too long for more than 99,99 % of all systems, not counting i586+. Especially if the driver is fine-tuned to give maximum throughput, this may be bad. OTOH, the DOS drivers I heared about use delays and would break on underclocked ISA busses if the n * ISA_HZ delay was needed. Maybe somebody having a configurable ISA bus speed and some problematic chips can test it ... -- Fun things to slip into your budget "I [Meow Cat] sliped in 'Legal fees for firing Jim (Jim's my [his] boss).' Jim approved the budget and was fired when upper management saw the budget." -- 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/