x86: fix debug message of CPU clock speed
Impact: Fixes incorrect printk 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 <isimatu.yasuaki@jp.fujitsu.com> Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
parent
5ee81007
Please register or sign in to comment