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Wysocki" , Sumit Gupta Cc: viresh.kumar@linaro.org, pierre.gondois@arm.com, zhenglifeng1@huawei.com, ionela.voinescu@arm.com, lenb@kernel.org, robert.moore@intel.com, corbet@lwn.net, rdunlap@infradead.org, ray.huang@amd.com, gautham.shenoy@amd.com, mario.limonciello@amd.com, perry.yuan@amd.com, zhanjie9@hisilicon.com, linux-pm@vger.kernel.org, linux-acpi@vger.kernel.org, linux-doc@vger.kernel.org, acpica-devel@lists.linux.dev, linux-kernel@vger.kernel.org, linux-tegra@vger.kernel.org, treding@nvidia.com, jonathanh@nvidia.com, vsethi@nvidia.com, ksitaraman@nvidia.com, sanjayc@nvidia.com, nhartman@nvidia.com, bbasu@nvidia.com Date: Thu, 05 Feb 2026 15:10:09 +0200 In-Reply-To: References: <20260129104817.3752340-1-sumitg@nvidia.com> <20260129104817.3752340-5-sumitg@nvidia.com> Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable User-Agent: Evolution 3.56.2 (3.56.2-2.fc42) Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 On Tue, 2026-02-03 at 13:43 +0100, Rafael J. Wysocki wrote: > On Thu, Jan 29, 2026 at 11:49=E2=80=AFAM Sumit Gupta = wrote: > >=20 > > Add cppc_get/set_min_perf() and cppc_get/set_max_perf() APIs to read an= d > > write the MIN_PERF and MAX_PERF registers. > >=20 > > Also add sysfs interfaces (min_perf, max_perf) in cppc_cpufreq driver > > to expose these controls to userspace. The sysfs values are in frequenc= y > > (kHz) for consistency with other cpufreq sysfs files. >=20 > But this is not cpufreq and it is not consistent. Just my 2 cents to add: CPPC and Intel CPUs don't use kHz for performance scaling. We should avoid introducing additional kHz-based interfaces where possible, since the performance units <-> kHz translation may become more complex over time than today. Future implementations could involve non-linear relationships and reduced accuracy. Minimizing kHz interfaces now may help reduce future work. Thanks, Artem.