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Index: website/content/en/status/report-2026-04-2026-06/cppc.adoc
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+=== Collaborative Processor Performance Control (CPPC)
+
+Contact: Olivier Certner <olce@FreeBSD.org> +
+Contact: ShengYi Hung <aokblast@FreeBSD.org>
+
+Collaborative Processor Performance Control (CPPC) is a standard introduced by ACPI to allow the OS to manage performance and, conversely, efficiency levels of CPUs thanks to an abstract performance scale in general uncorrelated to and more fine-grained than mere frequency levels.
+
+Work is ongoing again after another kickoff at the Halifax Hackathon end of June.
+
+In the works are:
+
+- New minimum, maximum and desired performance knobs for the Intel driver (`hwpstate_intel(4)`).
+- Teach `powerd(8)` about these knobs, and provide basic policies around them.
+- A knob to set EPP for all CPUs at once, and probably for the minimum, maximum and desired performance values as well.
+- Conditional enablement of the AMD driver (`hwpstate_amd(4)`) on ACPI's `_CPC` table presence.
+ A knob will allow to bypass this check, and possibly also whether the CPPC features are reported by CPUID.
+- A global profile knob with predefined values (such as "Balanced", "Performance", etc.), which sets all other more fine-grained knobs.
+ Setting a fine-grained knob explicitly will switch the profile to "Custom".
+
+A number of preliminary cleanups and fixes have been committed end of June.
+
+Sponsor: The FreeBSD Foundation

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