[Unstable][PATCH 0/3] Add support for CPPC values for Zen6

[Yo-Jung Leo Lin (AMD)]

BugLink: https://bugs.launchpad.net/bugs/2167550

[ Impact ]

This is a patch series as part of the effort to enable Zen 6 client platform support on Ubuntu Stonking kernel.

The highest frequency a core supports is important to be able to forecast capacity calculations. This information ideally comes from the hardware, but the interface that provides it is guarded behind ACPI 6.7.

That means the patches for reading it can't be released until ACPI 6.7.

Since platform schedules are imminent, I decided to add some hardcoded values. These aren't perfect (some OPNs will vary), but they at least get capacity calculations closer to right.

They can help platform performance by up to 50%, so they're quite important.

[ Fix ]

Pick up the following patch series:

1. [PATCH 0/3] Zen6 client CPPC

[ Test plan ]

For max frequency in each core type, confirmed that the max frequency changes to hard-coded values in the patch accordingly (/sys/devices/system/cpu/cpufreq/policyX/scaling_max_freq)

1. performance core: 5025000
2. low_power core: 2399000
3. efficiency core: 3524000

[ Were problems could occur ]

This includes refactor for AMD's cpufeq calculation algorithm. Wrong refactors may impact performance on older Zen platforms.

[ Additional Information ]

https://lore.kernel.org/linux-pm/20260831194428.2287055-1-mario.limonciello@amd.com/

Follow up patches will be posted later using the ACPI 6.7 interface once the ACPI 6.7 spec is released. We should plan to include them as well later (even if after platform launches).

Mario Limonciello (3):
  UBUNTU: SAUCE: ACPI: CPPC: Refactor boost ratio handling
  UBUNTU: SAUCE: cpufreq/acpi-cpufreq: Use amd_get_boost_ratio()
  UBUNTU: SAUCE: cpufreq/amd-pstate: Get Highest Freq for a CPU

 arch/x86/kernel/acpi/cppc.c    | 166 ++++++++++++++++++++++-----------
 drivers/cpufreq/acpi-cpufreq.c |  17 ++--
 drivers/cpufreq/amd-pstate.c   |  20 ++--
 include/acpi/cppc_acpi.h       |  14 ++-
 4 files changed, 143 insertions(+), 74 deletions(-)

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2.43.0