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Date:   Fri, 6 Jan 2023 12:11:54 +0100
From:   Borislav Petkov <bp@alien8.de>
To:     Ingo Molnar <mingo@kernel.org>
Cc:     "Zhang, Rui" <rui.zhang@intel.com>,
        "Hansen, Dave" <dave.hansen@intel.com>,
        "ak@linux.intel.com" <ak@linux.intel.com>,
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        "mingo@redhat.com" <mingo@redhat.com>,
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        "kan.liang@linux.intel.com" <kan.liang@linux.intel.com>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH 1/2] perf/x86/rapl: Add support for Intel Meteor Lake
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On Fri, Jan 06, 2023 at 11:56:18AM +0100, Ingo Molnar wrote:
> It's a trade-off in any case: there's a point where quirk flags or even 
> feature flags become harder to read and harder to maintain than cleanly 
> separated per model driver functions.

Yeah, no, singular: a synthetic feature *flag*: X86_FEATURE_RAPL.

cpu/intel.c can set it and driver can test it.

Everything else inside the driver.

Until Intel can get their act together and actually do a CPUID bit like AMD. :-P

But when you think about it, whether the model matching happens in the driver or
in cpu/intel.c doesn't matter a whole lot.

All that matters is, they should finally give it a CPUID bit.

-- 
Regards/Gruss,
    Boris.

https://people.kernel.org/tglx/notes-about-netiquette