Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753208AbXIPKrY (ORCPT ); Sun, 16 Sep 2007 06:47:24 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751373AbXIPKrR (ORCPT ); Sun, 16 Sep 2007 06:47:17 -0400 Received: from pne-smtpout4-sn2.hy.skanova.net ([81.228.8.154]:44771 "EHLO pne-smtpout4-sn2.hy.skanova.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751326AbXIPKrR (ORCPT ); Sun, 16 Sep 2007 06:47:17 -0400 Date: Sun, 16 Sep 2007 13:47:13 +0300 From: Sami Farin To: Linux kernel Mailing List Subject: TSC && HPET calibration Message-ID: <20070916104713.i3gu2p43ciifjc55@m.safari.iki.fi> Mail-Followup-To: Linux kernel Mailing List MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline User-Agent: Mutt/1.5.16 (2007-09-13) Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1965 Lines: 39 /var/log # grep -Ei "hpet|tsc" dmesg-2.6.19.7 dmesg.2.6.22.6-x86_64 dmesg-2.6.19.7:ACPI: HPET (v001 INTEL DQ965GF 0x000015db MSFT 0x01000013) @ 0x3e6f2000 dmesg-2.6.19.7:ACPI: HPET id: 0x8086a201 base: 0xfed00000 dmesg-2.6.19.7:[ 34.337155] hpet0: at MMIO 0xfed00000, IRQs 2, 8, 0 dmesg-2.6.19.7:[ 34.337296] hpet0: 3 64-bit timers, 14318180 Hz [*] dmesg-2.6.19.7:[ 34.338350] Using HPET for base-timer dmesg-2.6.19.7:[ 34.594096] checking TSC synchronization across 2 CPUs: passed. dmesg-2.6.19.7:[ 0.215896] hpet_resources: 0xfed00000 is busy dmesg-2.6.19.7:[ 7.794166] Time: tsc clocksource has been installed. dmesg.2.6.22.6-x86_64:ACPI: HPET 3E6F2000, 0038 (r1 INTEL DQ965GF 1741 MSFT 1000013) dmesg.2.6.22.6-x86_64:ACPI: HPET id: 0x8086a201 base: 0xfed00000 dmesg.2.6.22.6-x86_64:[ 0.000000] hpet clockevent registered dmesg.2.6.22.6-x86_64:[ 0.000000] TSC calibrated against HPET dmesg.2.6.22.6-x86_64:[ 23.917469] checking TSC synchronization [CPU#0 -> CPU#1]: dmesg.2.6.22.6-x86_64:[ 23.937970] Measured 196 cycles TSC warp between CPUs, turning off TSC clock. dmesg.2.6.22.6-x86_64:[ 23.938030] Marking TSC unstable due to check_tsc_sync_source failed dmesg.2.6.22.6-x86_64:[ 23.968187] Time: hpet clocksource has been installed. dmesg.2.6.22.6-x86_64:[ 23.997754] hpet_acpi_add: no address or irqs in _CRS # grep MHz /proc/cpuinfo cpu MHz : 2797.203 cpu MHz : 2797.203 # calc 2797203000/196 ~14271443.87755102040816326531 [*] so, does TSC calibration against HPET screw up TSC synchronization? I have Intel(R) Pentium(R) D CPU 2.80GHz and DQ965GF motherboard, BIOS v.5953. -- Do what you love because life is too short for anything else. - 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/