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Wysocki" , Linux PM Cc: Shawn Guo , Qais Yousef , LKML , Viresh Kumar , Prashanth Prakash , Pierre Gondois , Linux ACPI References: <8605612.T7Z3S40VBb@rafael.j.wysocki> <22867781.EfDdHjke4D@rafael.j.wysocki> Content-Language: en-US From: Mario Limonciello In-Reply-To: <22867781.EfDdHjke4D@rafael.j.wysocki> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-ClientProxiedBy: SA9PR13CA0111.namprd13.prod.outlook.com (2603:10b6:806:24::26) To DS7SPRMB0010.namprd12.prod.outlook.com (2603:10b6:8:87::8) 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: DS7SPRMB0010:EE_|DM3PR12MB9349:EE_ X-MS-Office365-Filtering-Correlation-Id: 69863a3d-eb9b-4d28-646d-08ddfc51b787 X-MS-Exchange-SenderADCheck: 1 X-MS-Exchange-AntiSpam-Relay: 0 X-Microsoft-Antispam: BCL:0;ARA:13230040|366016|376014|1800799024; X-Microsoft-Antispam-Message-Info: =?utf-8?B?MEFaTXorcjVyeEJ2N0J0UnZ5R1BHdGhNc0lXZWZ0cTVYV3ZpZDBSUkRmN1Fx?= =?utf-8?B?Tlk4RC9VTWxLQkVDSkZRT05FRG5XWTEvTmNYK0ppelpySDRsc1JlVVJ0NHdZ?= =?utf-8?B?TTJXTWxxL0N3UG5oL1o2ZFZseThnS3VreTRjZGJ4VVdXVmw5OXU1SmtLTkE2?= =?utf-8?B?aERicFc2dDRmb2IzWmhvSnIxR1k0MlFYZENFY3EzWndHd1JLOXpzdmVHL21x?= =?utf-8?B?NjJwd05YWTJPb2JGVVl3NGhjZkJvY2ovY2ZZQnE5UDdESDZjbXRsQjRnaEtL?= =?utf-8?B?U1VoMFI2ZzY3T1RJdTcvbVBJVVgwT20rU0pMaERYSWZFSXYwSG5wTkU1dXZO?= =?utf-8?B?TFAwemdpUjNySEJjUVBhRXNkRUwzdWx2K0FoODZaNEJmTmJ3bFAzcE1DbUQ3?= =?utf-8?B?dTVaVFlzc1NqcHJadCtjbXljaUlrbGhRL0ZtNXpleW9xREZEa0NreHBDbDUr?= =?utf-8?B?dFVUa3hVZmNQSWF5MHhHN0dYYll4dmx3UUJWTDZGVVcvK2NXTW4zVU9yaFN0?= =?utf-8?B?NjIyMkdOLzNuNFF1QlpZaGRJaGpBSGFsYXpiQ0NDUFl5YktQeUpQaXFoVHNn?= =?utf-8?B?bEFiQU13WHZXUGhmNHBkUnV1aE0zVFluWnJjeVRZcFFnUERHQnpFU0doLzRI?= =?utf-8?B?NjVxWWxtcjl6cHU0dnU2amhjclN3Nis4NWV6VzVqcXNOSDJJS1pma3VlbXpw?= =?utf-8?B?dktIUHRWaUUrK2lzZU55REY0dCtXcFRPMGZqUitGSXgxcUtTOGFiL1ZKelJV?= =?utf-8?B?aFZZcGhmL0RQOFZveitBWGlWNkphVWVnUTE5SUxHSkNPSTMxRS9qZTBZcmNX?= =?utf-8?B?dEdjVFpVMVBVR0IrVWMvRko3RVZrWW1HdWpsRnRvTmhhRzhleWpydjdWMnpC?= =?utf-8?B?dWdWZVpYbjNFbDZ2dEF0d3h4YkgwckQxbmVXczNmUTNvTW5aTlRJL0ZtaVp4?= =?utf-8?B?a2prK2ZqQVJUM3dSTksrRTZ0MllwMkFuT0xhOFU5TjN2MWtXakZKSUtaMm1n?= =?utf-8?B?ZWhNaVR6N1dkZ3JYVkEyRlFIQzhjMkFOVkFuWjBWVUUrVGxXYmdWZ21wMmxh?= =?utf-8?B?akZ5RGJLdVdlTlBmcGh0RlNTUWR3WGFoUjl4NktxcmtjSlpERWNhMVBGYlNs?= =?utf-8?B?M0Y4enRjakdqaFYxNUNPUkQyZytSS1d6WUw1QnM5azMzaHI1dHV6ekpMTmcr?= =?utf-8?B?ajg2aU83OE02VjBaR3N0enB4QmNsVWVyQzBMNXZPSFgvMVJXekNmZ3dHY09H?= =?utf-8?B?RzdCT0E2SFovdnVkK2Zkak80cXcxMms0aGV2Sk1hWUdDcUNjSndkYVU2ZVd5?= =?utf-8?B?eHcxbFJoeGtqRkNBckU2YXE5bmNNT3lnQUFtUXhSaC9QM3I2cnY2dzhGclBn?= =?utf-8?B?TlZRUitUOXEyRDhnbnVKVHd5anYzeG5uUnE0cWNwZXNBRjBZSHBzMlRsTXlI?= =?utf-8?B?NEtOM0pZWGJ6OTRZalVMbEhiYmd4elBEcjIrRjc2OUU3Y1I2b01WNnpGcytI?= =?utf-8?B?bGVwbEpYZVpjRlBDTTZpMGc0cVNFZUt1b0xkcER3eDQyMGQwR0ppR01OZ2FJ?= =?utf-8?B?cnB3M2J2c1grN092QWcyRzJhckhPUEFMMUcvdUhvTDFReUwzbUJVa3d6cERU?= =?utf-8?B?ZnMxOHpsdTNJWWo0aWkwRzNkWFJVTXhDUHNQV2pEYVlMN2VTOGU1WkhpRlJU?= =?utf-8?B?SkFVTjJPYjl2RUJKU09Yck0xZlN4WGFlWXEzUWR4ZTBwcm5YSXcrL05DNHp1?= =?utf-8?B?VmRvOEU5b1NkNmdUUDhVUStRaXFRdW82RFNxSkpxSnYwK05Lc0dUcWJMMito?= =?utf-8?B?ZklmcUhiWTFDUDdWYTZFM0IzMXk4bDdIcGZlOHN0b1RZb21HUllOa2Y2a2hk?= =?utf-8?B?Nm83d2xaOXBQazU3R0o2eTR0cUlSaFZ1ZnM3VEhoN1lVU2NOYWtPOHBKUW1y?= =?utf-8?Q?atFQPwmPUu0=3D?= X-Forefront-Antispam-Report: CIP:255.255.255.255;CTRY:;LANG:en;SCL:1;SRV:;IPV:NLI;SFV:NSPM;H:DS7SPRMB0010.namprd12.prod.outlook.com;PTR:;CAT:NONE;SFS:(13230040)(366016)(376014)(1800799024);DIR:OUT;SFP:1101; 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Wysocki wrote: > From: Rafael J. Wysocki > > If cppc_get_transition_latency() returns CPUFREQ_ETERNAL to indicate a > failure to retrieve the transition latency value from the platform > firmware, the CPPC cpufreq driver will use that value (converted to > microseconds) as the policy transition delay, but it is way too large > for any practical use. > > Address this by making the driver use the cpufreq's default > transition latency value (in microseconds) as the transition delay > if CPUFREQ_ETERNAL is returned by cppc_get_transition_latency(). > > Fixes: d4f3388afd48 ("cpufreq / CPPC: Set platform specific transition_delay_us") > Cc: 5.19+ # 5.19 > Signed-off-by: Rafael J. Wysocki Reviewed-by: Mario Limonciello (AMD) > --- > drivers/cpufreq/cppc_cpufreq.c | 14 ++++++++++++-- > 1 file changed, 12 insertions(+), 2 deletions(-) > > --- a/drivers/cpufreq/cppc_cpufreq.c > +++ b/drivers/cpufreq/cppc_cpufreq.c > @@ -308,6 +308,16 @@ static int cppc_verify_policy(struct cpu > return 0; > } > > +static unsigned int get_transition_latency_from_cppc(unsigned int cpu) > +{ > + unsigned int transition_latency_ns = cppc_get_transition_latency(cpu); > + > + if (transition_latency_ns == CPUFREQ_ETERNAL) > + return CPUFREQ_DEFAULT_TRANSITION_LATENCY_NS / NSEC_PER_USEC; > + > + return transition_latency_ns / NSEC_PER_USEC; > +} > + > /* > * The PCC subspace describes the rate at which platform can accept commands > * on the shared PCC channel (including READs which do not count towards freq > @@ -330,12 +340,12 @@ static unsigned int cppc_cpufreq_get_tra > return 10000; > } > } > - return cppc_get_transition_latency(cpu) / NSEC_PER_USEC; > + return get_transition_latency_from_cppc(cpu); > } > #else > static unsigned int cppc_cpufreq_get_transition_delay_us(unsigned int cpu) > { > - return cppc_get_transition_latency(cpu) / NSEC_PER_USEC; > + return get_transition_latency_from_cppc(cpu); > } > #endif > > > >