From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 374A319A; Sun, 24 Aug 2025 00:08:11 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=198.137.202.133 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1755994092; cv=none; b=On5gLs5t45pO8ABmIyYMTjqCHUmhKorIeSAQsXSBDtZsIppO9+AocU/XhjNj2hvWO/0BrktIIyw8C+7l4ukTYv0rF9y/p12VbAIhbqJISgwxfNuaEgsZbb1mYIH5u60Od+2yyVOG8xL3HAHdBr1d9Oh75zFcIcTo2xzda4bXi8c= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1755994092; c=relaxed/simple; bh=L9aGCyqYIqfiE/709OdRQZek+aVPISbBSeqD8LeS+PY=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=S3TdV2ZP5iwM/4vW7A6CTxcrntEEIaebXQmx9Yx7Iziqr8c9Cz1I8PTS/5oryRWuhyrbhtXTG78Egf0CEn4aofE+sMslChI5ivSUjrL5I2VezYOvZhSgRf+5BnDsCENl6+Bs5zyfsdyMIi/DjtY4cyWx5GsqLNa/1ieygS5f0Q4= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=infradead.org; spf=none smtp.mailfrom=infradead.org; dkim=pass (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b=13TqfuMa; arc=none smtp.client-ip=198.137.202.133 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=infradead.org Authentication-Results: smtp.subspace.kernel.org; spf=none smtp.mailfrom=infradead.org Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b="13TqfuMa" DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=bombadil.20210309; h=Content-Transfer-Encoding: Content-Type:In-Reply-To:From:References:Cc:To:Subject:MIME-Version:Date: Message-ID:Sender:Reply-To:Content-ID:Content-Description; bh=MyBjjN2I/3jlsDrVJT+yGV+wBVpUEwoIMa9ewpZMCMg=; b=13TqfuMa5/zhkRt1zTNt8DhjeH d7iQITJGOl0IJWojBPtm6GzoTnyNr5cmPKHVCauU0ACUxyJbiv36OckcHHWc/10jTi61ty7ZZZ9PC pvP6X9nmj/dtb7/tZa4OdA/gsr3beaKLMxsy9xtG+XBTU5hRv23DYpvCL0dxpAUc4wtzEgOM2icI4 6RrgjZfEH9POix9PWwuL+QPjurX3mP0jng2c+Bzs0v2N9Z7t2EWvMzemOJS2X8miZYcY8P5NV6m2W pBbIhMmbQplHRrd4Ndt+2hgmAV+71wRxWZ15Ninr6FcrkiiAwe0y3fGmACK5TT5D538ALyoiuSuFG jSAPqudQ==; Received: from [50.53.25.54] (helo=[192.168.254.17]) by bombadil.infradead.org with esmtpsa (Exim 4.98.2 #2 (Red Hat Linux)) id 1upyHD-00000005U69-0Xmu; Sun, 24 Aug 2025 00:08:03 +0000 Message-ID: <769e0ce4-1f96-4de5-a8a9-48166d6e3a91@infradead.org> Date: Sat, 23 Aug 2025 17:08:01 -0700 Precedence: bulk X-Mailing-List: linux-acpi@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v2 6/7] cpufreq: CPPC: Add sysfs for min/max_perf and perf_limited To: Sumit Gupta , rafael@kernel.org, viresh.kumar@linaro.org, lenb@kernel.org, robert.moore@intel.com, corbet@lwn.net, pierre.gondois@arm.com, zhenglifeng1@huawei.com, ray.huang@amd.com, gautham.shenoy@amd.com, mario.limonciello@amd.com, perry.yuan@amd.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 Cc: linux-tegra@vger.kernel.org, treding@nvidia.com, jonathanh@nvidia.com, vsethi@nvidia.com, ksitaraman@nvidia.com, sanjayc@nvidia.com, bbasu@nvidia.com References: <20250823200121.1320197-1-sumitg@nvidia.com> <20250823200121.1320197-7-sumitg@nvidia.com> Content-Language: en-US From: Randy Dunlap In-Reply-To: <20250823200121.1320197-7-sumitg@nvidia.com> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit On 8/23/25 1:01 PM, Sumit Gupta wrote: > Add sysfs interfaces for Minimum Performance, Maximum Performance > and Performance Limited Register in the cppc_cpufreq driver. > > Signed-off-by: Sumit Gupta > --- > .../ABI/testing/sysfs-devices-system-cpu | 43 +++++++++++++++++++ > 1 file changed, 43 insertions(+) > > diff --git a/Documentation/ABI/testing/sysfs-devices-system-cpu b/Documentation/ABI/testing/sysfs-devices-system-cpu > index ab8cd337f43a..4bce0dbc48c9 100644 > --- a/Documentation/ABI/testing/sysfs-devices-system-cpu > +++ b/Documentation/ABI/testing/sysfs-devices-system-cpu > @@ -327,6 +327,49 @@ Description: Energy performance preference > > This file is only present if the cppc-cpufreq driver is in use. > > +What: /sys/devices/system/cpu/cpuX/cpufreq/min_perf > +Date: Aug 2025 > +Contact: linux-pm@vger.kernel.org > +Description: Minimum Performance Preferably these 4 lines above use tab(s) after the ':' for indentation instead of spaces. (in 3 places, i.e., each sysfs file entry). > + > + Read/write a 32 bits value from/to this file. This file > + conveys the minimum performance level at which the platform > + may run. Minimum performance may be set to any performance > + value in the range [Lowest Performance, Highest Performance], > + inclusive but must be set to a value that is less than or > + equal to that specified by the Maximum Performance Register. > + > + Writing to this file only has meaning when Autonomous Selection > + is enabled. > + > + This file is only present if the cppc-cpufreq driver is in use. > + > +What: /sys/devices/system/cpu/cpuX/cpufreq/max_perf > +Date: Aug 2025 > +Contact: linux-pm@vger.kernel.org > +Description: Minimum Performance > + > + Read/write a 32 bits value from/to this file. This file conveys > + the maximum performance level at which the platform may run. > + Maximum performance may be set to any performance value in the > + range [Lowest Performance, Highest Performance], inclusive. > + > + Writing to this file only has meaning when Autonomous Selection is > + enabled. > + > + This file is only present if the cppc-cpufreq driver is in use. > + > +What: /sys/devices/system/cpu/cpuX/cpufreq/perf_limited > +Date: Aug 2025 > +Contact: linux-pm@vger.kernel.org > +Description: Minimum Performance > + > + Read/write a 32 bits value from/to this file. This file indicates > + to OSPM that an unpredictable event has limited processor > + performance, and the delivered performance may be less than > + desired/minimum performance. > + > + This file is only present if the cppc-cpufreq driver is in use. > > What: /sys/devices/system/cpu/cpu*/cache/index3/cache_disable_{0,1} > Date: August 2008 Reviewed-by: Randy Dunlap Thanks. -- ~Randy