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Shenoy" , Perry Yuan Cc: "open list:X86 ARCHITECTURE (32-BIT AND 64-BIT)" , "open list:CPU FREQUENCY SCALING FRAMEWORK" , Mario Limonciello References: <20250219210302.442954-1-superm1@kernel.org> <20250219210302.442954-18-superm1@kernel.org> <59c1fb63-1342-4aed-8b4d-f07c263cc74f@amd.com> <767f4c49-7183-4aef-940f-3a811319eb11@kernel.org> Content-Language: en-US From: Dhananjay Ugwekar In-Reply-To: <767f4c49-7183-4aef-940f-3a811319eb11@kernel.org> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit X-ClientProxiedBy: PN3PR01CA0187.INDPRD01.PROD.OUTLOOK.COM (2603:1096:c01:be::10) To LV8PR12MB9207.namprd12.prod.outlook.com (2603:10b6:408:187::15) Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-MS-PublicTrafficType: Email X-MS-TrafficTypeDiagnostic: LV8PR12MB9207:EE_|LV3PR12MB9235:EE_ X-MS-Office365-Filtering-Correlation-Id: 97b412b8-bac8-4a27-a7df-08dd5557ee17 X-MS-Exchange-SenderADCheck: 1 X-MS-Exchange-AntiSpam-Relay: 0 X-Microsoft-Antispam: BCL:0;ARA:13230040|376014|1800799024|366016; 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>>> +        ret = cppc_set_perf(policy->cpu, &perf_ctrls); >> >> I'm thinking do we need this "setting of desired_perf" as a part of shmem_cppc_enable, >> one thing is we're not doing it in the "msr_" counterpart >> also, I guess this would be taken care as part of amd_pstate_epp_set_policy()->amd_pstate_epp_update_limit()->amd_pstate_update_perf() > > Great point, agreed will drop it. > >> >>>       } >>>   -    cppc_enabled = enable; >>>       return ret; >>>   } >>>     DEFINE_STATIC_CALL(amd_pstate_cppc_enable, msr_cppc_enable); >>>   -static inline int amd_pstate_cppc_enable(bool enable) >>> +static inline int amd_pstate_cppc_enable(struct cpufreq_policy *policy) >>>   { >>> -    return static_call(amd_pstate_cppc_enable)(enable); >>> +    return static_call(amd_pstate_cppc_enable)(policy); >>>   } >>>     static int msr_init_perf(struct amd_cpudata *cpudata) [Snip] >>>   @@ -1649,31 +1591,21 @@ static int amd_pstate_epp_set_policy(struct cpufreq_policy *policy) >>>       return 0; >>>   } >>>   -static int amd_pstate_epp_reenable(struct cpufreq_policy *policy) >>> -{ >>> -    int ret; >>> - >>> -    ret = amd_pstate_cppc_enable(true); >>> -    if (ret) >>> -        pr_err("failed to enable amd pstate during resume, return %d\n", ret); >>> - >>> - >>> -    return amd_pstate_epp_update_limit(policy); >>> -} >>> - >>>   static int amd_pstate_epp_cpu_online(struct cpufreq_policy *policy) >>>   { >>>       struct amd_cpudata *cpudata = policy->driver_data; >>>       int ret; >>>   -    pr_debug("AMD CPU Core %d going online\n", cpudata->cpu); >>> +    pr_debug("AMD CPU Core %d going online\n", policy->cpu); >>>   -    ret = amd_pstate_epp_reenable(policy); >>> +    ret = amd_pstate_cppc_enable(policy); >>>       if (ret) >>>           return ret; >>> + >>>       cpudata->suspended = false; >> >> Do we need this here?, shouldn't only resume() have this statement? > > The reason I had in mind for it was this sequence: > * Suspend > * CPU goes offline > * CPU goes online > * Resume > > But I don't think that's realistic even with parallel boot.  I will drop this. Also I have one doubt, why do we need to keep track if the system is suspended ? Won't the idle subsystem have safeguards to prevent CPU offline while the system is being suspended ? Haven't gone through that code, just checking if you have an idea about it.