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Re: CVS commit: src/sys/arch/x86/x86

On Mon, Aug 08, 2011 at 11:18:35AM +0000, Jared D. McNeill wrote:
> Module Name:  src
> Committed By: jmcneill
> Date:         Mon Aug  8 11:18:34 UTC 2011
> Modified Files:
>       src/sys/arch/x86/x86: tsc.c
> Log Message:
> If the USE_PLATFORM_CLOCK flag is set in the FADT, it indicates that OSPM
> should use a platform provided timer (either HPET or the PM timer). A
> platform may set this flag if internal processor clock(s) cannot provide
> consistent monotonically non-decreasing counters. Set TSC quality to -100
> if this flag is set.

We should not really trust ACPI/FADT here. See acpicpu(4) how this is
derived from the actual CPU information. Additionally, I suggested decreasing
the quality of tsc(9) based on this information a long time ago, but joerg@
had concerns about this.

- Jukka.

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