Re: [PATCH v6 0/2] ACPI / cpufreq: CPPC: Add ospm_nominal_perf support
"Rafael J. Wysocki (Intel)" <[email protected]>
| Newsgroups | org.kernel.vger.linux-pm,org.kernel.vger.linux-acpi,org.kernel.vger.linux-kernel,org.kernel.vger.linux-tegra |
|---|---|
| Message-ID | <CAJZ5v0jdF+PYjxTqUSp_oJiCcPR4UUrQdBPt0K3f08BLRB4L4g@mail.gmail.com> |
On Fri, Jul 17, 2026 at 11:54 PM Sumit Gupta <[email protected]> wrote: > > This series adds support for the OSPM Nominal Performance register > (ACPI 6.6, Section 8.4.6.1.2.6) to the CPPC ACPI and cpufreq drivers. > > Unlike the read-only Nominal Performance register, OSPM Nominal > Performance is writable and lets OSPM request a nominal level below > the platform-reported nominal. The platform treats performance above > this level as boost and below as throttle for its power and thermal > decisions. > > Patch 1: adds the cppc_{get,set}_ospm_nominal_perf() helpers, a > per-policy cpufreq sysfs attribute (ospm_nominal_freq, in kHz), and > hooks the register into the OSPM-set save/restore table. > > Patch 2: reflects the OSPM nominal in the cpufreq policy so that boost > and the frequency limits stay consistent with the register. > > This series applies on top of the series > "cpufreq: CPPC: Preserve OSPM-set registers across hotplug and unload", > which provides the save/restore table that patch 1 hooks into: > https://lore.kernel.org/lkml/[email protected]/ > > v5[5] -> v6: > - New patch 2: reflect the OSPM nominal in the policy's boost state > and frequency limits. > - Patch 1: > - write only policy->cpu instead of looping over policy->cpus with > rollback. the register is treated as shared across a policy's CPUs. > - add the register to the OSPM-set save/restore table. Christian, Pierre, any chance to have a look at this, please? > Sumit Gupta (2): > ACPI: CPPC: Add ospm_nominal_perf support > cpufreq: CPPC: Reflect ospm_nominal_perf in boost and limits > > .../ABI/testing/sysfs-devices-system-cpu | 26 +++ > drivers/acpi/cppc_acpi.c | 32 ++++ > drivers/cpufreq/cppc_cpufreq.c | 166 +++++++++++++++++- > include/acpi/cppc_acpi.h | 10 ++ > 4 files changed, 226 insertions(+), 8 deletions(-) > > v5: https://lore.kernel.org/lkml/[email protected]/ > v4: https://lore.kernel.org/lkml/[email protected]/ > v3: https://lore.kernel.org/lkml/[email protected]/ > v2: https://lore.kernel.org/lkml/[email protected]/ > v1: https://lore.kernel.org/lkml/[email protected]/