On 2025/2/11 18:44, Viresh Kumar wrote: > On 11-02-25, 16:07, Sumit Gupta wrote: >> This patchset supports the Autonomous Performance Level Selection mode >> in the cppc_cpufreq driver. The feature is part of the existing CPPC >> specification and already present in Intel and AMD specific pstate >> cpufreq drivers. The patchset adds the support in generic acpi cppc >> cpufreq driver. > > Is there an overlap with: > > https://lore.kernel.org/all/20250206131428.3261578-1-zhenglifeng1@xxxxxxxxxx/ > > ? Ha, it looks like we're doing something very similar. > >> It adds a new 'cppc_cpufreq_epp' instance of the 'cppc_cpufreq' driver >> for supporting the Autonomous Performance Level Selection and Energy >> Performance Preference (EPP). >> Autonomous selection will get enabled during boot if 'cppc_auto_sel' >> boot argument is passed or the 'Autonomous Selection Enable' register >> is already set before kernel boot. When enabled, the hardware is >> allowed to autonomously select the CPU frequency within the min and >> max perf boundaries using the Engergy Performance Preference hints. >> The EPP values range from '0x0'(performance preference) to '0xFF' >> (energy efficiency preference). >> >> It also exposes the acpi_cppc sysfs nodes to update the epp, auto_sel >> and {min|max_perf} registers for changing the hints to hardware for >> Autonomous selection. >> >> In a followup patch, plan to add support to dynamically switch the >> cpufreq driver instance from 'cppc_cpufreq_epp' to 'cppc_cpufreq' and >> vice-versa without reboot. >> >> The patches are divided into below groups: >> - Patch [1-2]: Improvements. Can be applied independently. >> - Patch [3-4]: sysfs store nodes for Auto mode. Depend on Patch [1-2]. >> - Patch [5]: Support for 'cppc_cpufreq_epp'. Uses a macro from [3]. >> >> Sumit Gupta (5): >> ACPI: CPPC: add read perf ctrls api and rename few existing >> ACPI: CPPC: expand macro to create store acpi_cppc sysfs node >> ACPI: CPPC: support updating epp, auto_sel and {min|max_perf} from >> sysfs >> Documentation: ACPI: add autonomous mode ctrls info in cppc_sysfs.txt >> cpufreq: CPPC: Add cppc_cpufreq_epp instance for Autonomous mode >> >> Documentation/admin-guide/acpi/cppc_sysfs.rst | 28 ++ >> .../admin-guide/kernel-parameters.txt | 11 + >> drivers/acpi/cppc_acpi.c | 311 ++++++++++++++++-- >> drivers/cpufreq/cppc_cpufreq.c | 260 ++++++++++++++- >> include/acpi/cppc_acpi.h | 19 +- >> 5 files changed, 572 insertions(+), 57 deletions(-) >
