Re: [edk2] [PATCH] PcAtChipsetPkg AcpiTimerLib: Wait 363 ACPI timer counts to get TSC Freq

2016-08-17 Thread Kinney, Michael D
Reviewed-by: Michael Kinney > -Original Message- > From: Zeng, Star > Sent: Tuesday, August 16, 2016 7:27 PM > To: edk2-devel@lists.01.org > Cc: Zeng, Star ; Kinney, Michael D > ; > Gao, Liming

Re: [edk2] [PATCH] PcAtChipsetPkg AcpiTimerLib: Wait 363 ACPI timer counts to get TSC Freq

2016-08-17 Thread Kinney, Michael D
tar.z...@intel.com>; edk2-devel@lists.01.org > Cc: Kinney, Michael D <michael.d.kin...@intel.com>; Gao, Liming > <liming....@intel.com> > Subject: Re: [edk2] [PATCH] PcAtChipsetPkg AcpiTimerLib: Wait 363 ACPI timer > counts > to get TSC Freq > > > > On 17/08/

Re: [edk2] [PATCH] PcAtChipsetPkg AcpiTimerLib: Wait 363 ACPI timer counts to get TSC Freq

2016-08-17 Thread Paolo Bonzini
On 17/08/2016 04:26, Star Zeng wrote: > Compute the number of ticks to wait to measure TSC frequency. > Instead of (ACPI_TIMER_FREQUENCY / 1) = 357 and 357 * 1 = 357, > use 363 * 9861 = 3579543 Hz which is within 2 Hz of ACPI_TIMER_FREQUENCY. > 363 counts is a calibration time of

[edk2] [PATCH] PcAtChipsetPkg AcpiTimerLib: Wait 363 ACPI timer counts to get TSC Freq

2016-08-16 Thread Star Zeng
Compute the number of ticks to wait to measure TSC frequency. Instead of (ACPI_TIMER_FREQUENCY / 1) = 357 and 357 * 1 = 357, use 363 * 9861 = 3579543 Hz which is within 2 Hz of ACPI_TIMER_FREQUENCY. 363 counts is a calibration time of 101.4 uS. The idea comes from Michael and Paolo.