Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753921AbZA0I2w (ORCPT ); Tue, 27 Jan 2009 03:28:52 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1752202AbZA0I2o (ORCPT ); Tue, 27 Jan 2009 03:28:44 -0500 Received: from fgwmail5.fujitsu.co.jp ([192.51.44.35]:36816 "EHLO fgwmail5.fujitsu.co.jp" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752145AbZA0I2n (ORCPT ); Tue, 27 Jan 2009 03:28:43 -0500 Message-ID: <497EC3F8.6020100@jp.fujitsu.com> Date: Tue, 27 Jan 2009 17:21:12 +0900 From: Yasuaki Ishimatsu User-Agent: Thunderbird 1.5.0.12 (X11/20071019) MIME-Version: 1.0 To: linux-kernel@vger.kernel.org CC: mingo@redhat.com Subject: [PATCH 1/3] fix debug message of CPU clock speed References: <497EC23A.7050408@jp.fujitsu.com> In-Reply-To: <497EC23A.7050408@jp.fujitsu.com> Content-Type: text/plain; charset=ISO-2022-JP Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 4239 Lines: 115 LOCAL APIC is corrected by PM-Timer, when SMI occurred while LOCAL APIC is calibrated. In this case, LOCAL APIC debug message(Boot with apic=debug) is displayed correctly, however, CPU clock speed debug message is displayed wrongly . When SMI occured on my machine, which has 1.6GHz CPU, CPU clock speed is displayed 3622.0205 MHz as follow. CPU0: Intel(R) Xeon(R) CPU 5110 @ 1.60GHz stepping 06 Using local APIC timer interrupts. calibrating APIC timer ... ... lapic delta = 3773130 ... PM timer delta = 812434 APIC calibration not consistent with PM Timer: 226ms instead of 100ms APIC delta adjusted to PM-Timer: 1662420 (3773130) ..... delta 1662420 ..... mult: 71411249 ..... calibration result: 265987 ..... CPU clock speed is 3622.0205 MHz. =====> here ..... host bus clock speed is 265.0987 MHz. This patch fixes to displaying CPU clock speed correctly as follow. CPU0: Intel(R) Xeon(R) CPU 5110 @ 1.60GHz stepping 06 Using local APIC timer interrupts. calibrating APIC timer ... ... lapic delta = 3773131 ... PM timer delta = 812434 APIC calibration not consistent with PM Timer: 226ms instead of 100ms APIC delta adjusted to PM-Timer: 1662420 (3773131) TSC delta adjusted to PM-Timer: 159592409 (362220564) ..... delta 1662420 ..... mult: 71411249 ..... calibration result: 265987 ..... CPU clock speed is 1595.0924 MHz. ..... host bus clock speed is 265.0987 MHz. Signed-off-by: Yasuaki Ishimatsu --- arch/x86/kernel/apic.c | 23 +++++++++++++++++------ 1 file changed, 17 insertions(+), 6 deletions(-) Index: linux-2.6.29-rc2/arch/x86/kernel/apic.c =================================================================== --- linux-2.6.29-rc2.orig/arch/x86/kernel/apic.c 2009-01-27 11:04:40.000000000 +0900 +++ linux-2.6.29-rc2/arch/x86/kernel/apic.c 2009-01-27 12:29:03.000000000 +0900 @@ -535,7 +535,8 @@ static void __init lapic_cal_handler(str } } -static int __init calibrate_by_pmtimer(long deltapm, long *delta) +static int __init calibrate_by_pmtimer(long deltapm, long *delta, + long *deltatsc) { const long pm_100ms = PMTMR_TICKS_PER_SEC / 10; const long pm_thresh = pm_100ms / 100; @@ -569,6 +570,15 @@ static int __init calibrate_by_pmtimer(l pr_info("APIC delta adjusted to PM-Timer: " "%lu (%ld)\n", (unsigned long)res, *delta); *delta = (long)res; + + if (cpu_has_tsc) { + res = (((u64)(*deltatsc)) * pm_100ms); + do_div(res, deltapm); + apic_printk(APIC_VERBOSE, "TSC delta adjusted to " + "PM-Timer: %lu (%ld)\n", + (unsigned long)res, *deltatsc); + *deltatsc = (long)res; + } } return 0; @@ -579,7 +589,7 @@ static int __init calibrate_APIC_clock(v struct clock_event_device *levt = &__get_cpu_var(lapic_events); void (*real_handler)(struct clock_event_device *dev); unsigned long deltaj; - long delta; + long delta, deltatsc; int pm_referenced = 0; local_irq_disable(); @@ -609,9 +619,11 @@ static int __init calibrate_APIC_clock(v delta = lapic_cal_t1 - lapic_cal_t2; apic_printk(APIC_VERBOSE, "... lapic delta = %ld\n", delta); + deltatsc = (long)(lapic_cal_tsc2 - lapic_cal_tsc1); + /* we trust the PM based calibration if possible */ pm_referenced = !calibrate_by_pmtimer(lapic_cal_pm2 - lapic_cal_pm1, - &delta); + &delta, &deltatsc); /* Calculate the scaled math multiplication factor */ lapic_clockevent.mult = div_sc(delta, TICK_NSEC * LAPIC_CAL_LOOPS, @@ -629,11 +641,10 @@ static int __init calibrate_APIC_clock(v calibration_result); if (cpu_has_tsc) { - delta = (long)(lapic_cal_tsc2 - lapic_cal_tsc1); apic_printk(APIC_VERBOSE, "..... CPU clock speed is " "%ld.%04ld MHz.\n", - (delta / LAPIC_CAL_LOOPS) / (1000000 / HZ), - (delta / LAPIC_CAL_LOOPS) % (1000000 / HZ)); + (deltatsc / LAPIC_CAL_LOOPS) / (1000000 / HZ), + (deltatsc / LAPIC_CAL_LOOPS) % (1000000 / HZ)); } apic_printk(APIC_VERBOSE, "..... host bus clock speed is " -- 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/