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Wysocki" , Viresh Kumar Cc: linux-pm@vger.kernel.org, linux-acpi@vger.kernel.org, linux-kernel@vger.kernel.org, Len Brown , Jie Zhan , Lifeng Zheng , Pierre Gondois , Sudeep Holla , Ionela Voinescu , zhongqiu.han@oss.qualcomm.com References: <20260729100245.2628302-1-christian.loehle@arm.com> Content-Language: en-US From: Sumit Gupta In-Reply-To: Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit X-ClientProxiedBy: PN2PR01CA0055.INDPRD01.PROD.OUTLOOK.COM (2603:1096:c01:22::30) To BN9PR12MB5179.namprd12.prod.outlook.com (2603:10b6:408:11c::18) Precedence: bulk X-Mailing-List: linux-acpi@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-MS-PublicTrafficType: Email X-MS-TrafficTypeDiagnostic: BN9PR12MB5179:EE_|MN0PR12MB5979:EE_ X-MS-Office365-Filtering-Correlation-Id: 076f005b-3d10-4927-9613-08def1603d69 X-MS-Exchange-SenderADCheck: 1 X-MS-Exchange-AntiSpam-Relay: 0 X-Microsoft-Antispam: BCL:0;ARA:13230040|376014|7416014|23010399003|366016|1800799024|6133799003|56012099006|10067099003|4143699003|11063799006|22082099003|18002099003; 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Preserve that workaround > on systems reporting an older ACPI revision, but do not attempt the read > on ACPI 6.6 or later, where firmware no longer promises a readable value > and cppc-cpufreq can fall back to its cached OSPM request instead. > > cppc_get_perf() also reads Desired Performance while populating the > control values used during cppc-cpufreq initialization. Its only in-tree > caller overwrites that value with highest_perf before the controls are > first written, so the value is never consumed. > > Patches 1 and 2 provide minimal, backportable fixes for the two read > paths. Patch 3 simplifies the mainline API by no longer reading > Desired Performance through cppc_get_perf() on any ACPI revision. > > Changes since v2: > - Fall back to the cached OSPM request when reading Desired Performance > returns zero as suggested by Sumit Gupta. > - Pick up Reviewed-by tags from Zhongqiu Han for patches 2 and 3. > - Rebase onto v7.2-rc6 > > Christian Loehle (3): > ACPI: CPPC: Reject desired_perf reads on ACPI 6.6+ > ACPI: CPPC: Skip desired_perf read in cppc_get_perf() > ACPI: CPPC: Stop reading desired_perf in cppc_get_perf() For the entire series:   Reviewed-by: Sumit Gupta Thanks, Sumit