From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754815AbYGLHjb (ORCPT ); Sat, 12 Jul 2008 03:39:31 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1752573AbYGLHjY (ORCPT ); Sat, 12 Jul 2008 03:39:24 -0400 Received: from mx2.mail.elte.hu ([157.181.151.9]:32879 "EHLO mx2.mail.elte.hu" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752540AbYGLHjY (ORCPT ); Sat, 12 Jul 2008 03:39:24 -0400 Date: Sat, 12 Jul 2008 09:39:10 +0200 From: Ingo Molnar To: Cyrill Gorcunov Cc: "H. Peter Anvin" , Thomas Gleixner , "Maciej W. Rozycki" , LKML Subject: Re: [PATCH -tip] x86: apic LVTT - use APIC_DIVISOR on 64bit mode Message-ID: <20080712073910.GA10689@elte.hu> References: <20080709190237.GA21423@asus> <20080712060504.GB14714@elte.hu> <20080712072216.GA7010@asus> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20080712072216.GA7010@asus> User-Agent: Mutt/1.5.18 (2008-05-17) X-ELTE-VirusStatus: clean X-ELTE-SpamScore: -1.5 X-ELTE-SpamLevel: X-ELTE-SpamCheck: no X-ELTE-SpamVersion: ELTE 2.0 X-ELTE-SpamCheck-Details: score=-1.5 required=5.9 tests=BAYES_00 autolearn=no SpamAssassin version=3.2.3 -1.5 BAYES_00 BODY: Bayesian spam probability is 0 to 1% [score: 0.0000] Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org * Cyrill Gorcunov wrote: > @@ -329,7 +332,7 @@ static void __init calibrate_APIC_clock( > * > * No interrupt enable ! > */ > - __setup_APIC_LVTT(250000000, 0, 0); > + __setup_APIC_LVTT(4000000000, 0, 0); note how close it is to 2^32. For this to be unifiable later on this needs to be UL i guess, and this: > - calibration_result = result / HZ; > + calibration_result = result * APIC_DIVISOR / HZ; might overflow 32 bits. Ingo