Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754175AbXLJETA (ORCPT ); Sun, 9 Dec 2007 23:19:00 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751504AbXLJESw (ORCPT ); Sun, 9 Dec 2007 23:18:52 -0500 Received: from smtpq1.groni1.gr.home.nl ([213.51.130.200]:37206 "EHLO smtpq1.groni1.gr.home.nl" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751413AbXLJESv (ORCPT ); Sun, 9 Dec 2007 23:18:51 -0500 Message-ID: <475CBDD7.5050602@keyaccess.nl> Date: Mon, 10 Dec 2007 05:17:27 +0100 From: Rene Herman User-Agent: Thunderbird 2.0.0.9 (X11/20071031) MIME-Version: 1.0 To: Pavel Machek CC: Andi Kleen , Alan Cox , "David P. Reed" , linux-kernel@vger.kernel.org, Thomas Gleixner , Ingo Molnar , "H. Peter Anvin" 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> In-Reply-To: <20071209212513.GC24284@elf.ucw.cz> 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: 825 Lines: 25 On 09-12-07 22:25, Pavel Machek wrote: > On Sun 2007-12-09 17:59:08, Andi Kleen wrote: >> Yes, i guess switching to udelay at least on newer systems would >> be a good idea. I'm not quite sure about systems without TSC though. > > Something like this? (Warning, will not probably even compile on > x86-64, I do not have 64-bit compiler near me). > static inline void native_io_delay(void) > { > - asm volatile("outb %%al,$0x80" : : : "memory"); > + udelay(8); > } Alan, did you double-check that 8 us? I tried to but I seem to not have trustworthy documentation. 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/