Many Intel & AMD Power Management Improvements For Linux 6.12

The big set of power management updates for Linux 6.12 have landed.

On the Intel side there is now hybrid CPU capacity scaling support within the Intel P-State driver. This hybrid CPU capacity scaling support is particularly important for forthcoming Intel Core Ultra 200 Series "Lunar Lake" laptops with a mix of P and E cores while lacking SMT support. As a reminder, I'll have Intel Lunar Lake Linux support and benchmarks later this month on Phoronix after pre-ordering a laptop due to the lack of cooperation from Intel.

Also on the Intel P-State driver front is Granite Rapids and Sierra Forest support when functioning in the Out-Of-Band (OOB) mode. The Intel Idle driver also adds support for upcoming Intel Xeon 6 "Granite Rapids" processors. The Intel RAPL PowerCapping code also adds Arrow Lake U processor support.

The AMD power management has a lot too. The AMD P-State driver has reworked its calculations for AMD boost and AMD Preferred Core detection. The Run-Time Average Power Limiting (RAPL) code also has AMD Family 1Ah "Zen 5" CPU detection that is needed for power monitoring of AMD Zen 5 processors.

The Linux 6.12 power management code is also dropping the old LATENCY_MULTIPLIER code that slows down CPU frequency polling.

More details on all of the Linux 6.12 power management changes via this pull request. Similarly, the ACPI changes for Linux 6.12 were also submitted for some related power activity with this next kernel release.

Linux 6.12 is anticipated to be this year's Long Term Support (LTS) kernel version making these Intel and AMD changes all the more important. Linux 6.12 stable should be out in November.