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SubjectRe: [PATCH] x86 tsc: Add the Intel Denverton Processor to native_calibrate_tsc()

* Len Brown <lenb@kernel.org> wrote:

> From: Len Brown <len.brown@intel.com>
>
> The Intel Denverton microserver uses a 25 MHz TSC crystal,
> so we can derive its exact * TSC frequency
> using CPUID and some arithmetic, eg.
>
> TSC: 1800 MHz (25000000 Hz * 216 / 3 / 1000000)
>
> * 'exact' is only as good as the crystal, which should be +/- 20ppm
>
> Signed-off-by: Len Brown <len.brown@intel.com>
> ---
> arch/x86/kernel/tsc.c | 1 +
> 1 file changed, 1 insertion(+)
>
> diff --git a/arch/x86/kernel/tsc.c b/arch/x86/kernel/tsc.c
> index 46b2f41f8b05..b3e397a0f29d 100644
> --- a/arch/x86/kernel/tsc.c
> +++ b/arch/x86/kernel/tsc.c
> @@ -694,6 +694,7 @@ unsigned long native_calibrate_tsc(void)
> crystal_khz = 24000; /* 24.0 MHz */
> break;
> case INTEL_FAM6_SKYLAKE_X:
> + case INTEL_FAM6_ATOM_DENVERTON:
> crystal_khz = 25000; /* 25.0 MHz */
> break;
> case INTEL_FAM6_ATOM_GOLDMONT:

Already upstream, as per:

695085b4bc76 x86/tsc: Add the Intel Denverton Processor to native_calibrate_tsc()

Thanks,

Ingo

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