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Wysocki" , Huang Rui CC: , , , , Shuah Khan , , "Nathan Fontenot" , Deepak Sharma , Alex Deucher , Mario Limonciello , Shimmer Huang , "Perry Yuan" , Xiaojian Du , Viresh Kumar , Borislav Petkov , "Oleksandr Natalenko" , Meng Li , Wyes Karny Subject: [RESEND PATCH V9 2/7] acpi: cppc: Add get the highest performance cppc control Date: Fri, 13 Oct 2023 11:31:13 +0800 Message-ID: <20231013033118.3759311-3-li.meng@amd.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20231013033118.3759311-1-li.meng@amd.com> References: <20231013033118.3759311-1-li.meng@amd.com> MIME-Version: 1.0 X-Originating-IP: [10.180.168.240] X-ClientProxiedBy: SATLEXMB03.amd.com (10.181.40.144) To SATLEXMB04.amd.com (10.181.40.145) X-EOPAttributedMessage: 0 X-MS-PublicTrafficType: Email X-MS-TrafficTypeDiagnostic: CO1PEPF000042AB:EE_|DM4PR12MB5937:EE_ X-MS-Office365-Filtering-Correlation-Id: bc4f7448-d263-435f-eb7c-08dbcb9cf92b X-MS-Exchange-SenderADCheck: 1 X-MS-Exchange-AntiSpam-Relay: 0 X-Microsoft-Antispam: BCL:0; X-Microsoft-Antispam-Message-Info: aC+v3PdFnsJg513BsNyDyiR+fzv1FVxs+iDjlJn0hRSrDm7vEuUk1hqUmkmdtC/X7rvHC9zQQMMMS4zPSyChlaP53JFJ7nNZ6xBFNOOEhutzigjScU/v/oCVs2AzsMwk0BDPeJrldFzdAZx5hYfhpFzjtAcObWrzPYXy5clXPhBAru0F9cYrlgfCY0iEpDm4+RdYsh2XIb/R9DwIWSBcXfWB+Ads978aTSMDotCuqnZ8Ioa+IEV6PInPfBiFgdWPc7dZ5GhDJuPG4QcgmoktpOnwnKOXAIavkIOvZlV/YACd7s/ezVEY4Ttvd93yvWa/oH7pvN/+sMMay8NzgDWdg8fNvjQ4cuM4JqRDbrSg1phSyEgioIr/KZy9gWlk0kWelRROATTdPFovttkLbcUvg/z+oYC+GQJ893UGBluRonxwUkjqEoSPeVKQ3RXuy/+f5t6ar61R/trvbj2wq+TZ5QvY7dHa0r9ckVE5g9wcZpUuyR1i64q1AdUwvP8ACVGgbYN+gAeccxZxAStP9MtGN0Cf8oe8W9ViWV9GojMuT899xMtDyLIwAqDqbdy4Kegd1rU7wkV7ceTT7g2ysi6Y0gyOXDqzbiimSj++aUF5eEPFfWQw8gwceUf520aU14w0FD4eRqlfvgn+fls0qR26wo+HbE/NUiwlLr/EJ9dyDa7kD78gtOCsLRQJSJIB+7j1hkUPjdqzgiKrGHDemT+m4fMngosBXZSHExBmtrn0QlzBomAbVrJk0Q5ObqZcSN+uqpEadgKfiN26ImPUreWM9z18yyGIUfb+bjn/5dlH558= X-Forefront-Antispam-Report: CIP:165.204.84.17; CTRY:US; LANG:en; SCL:1; SRV:; IPV:CAL; SFV:NSPM; H:SATLEXMB04.amd.com; PTR:InfoDomainNonexistent; CAT:NONE; SFS:(13230031)(4636009)(346002)(39860400002)(396003)(376002)(136003)(230922051799003)(82310400011)(1800799009)(64100799003)(186009)(451199024)(46966006)(40470700004)(36840700001)(86362001)(82740400003)(36756003)(40460700003)(40480700001)(478600001)(2906002)(41300700001)(4326008)(966005)(7696005)(6666004)(7416002)(8676002)(8936002)(5660300002)(2616005)(426003)(1076003)(336012)(47076005)(70206006)(110136005)(70586007)(316002)(6636002)(16526019)(54906003)(26005)(36860700001)(356005)(81166007)(15583001)(36900700001); DIR:OUT; SFP:1101; X-OriginatorOrg: amd.com X-MS-Exchange-CrossTenant-OriginalArrivalTime: 13 Oct 2023 03:32:05.7392 (UTC) X-MS-Exchange-CrossTenant-Network-Message-Id: bc4f7448-d263-435f-eb7c-08dbcb9cf92b X-MS-Exchange-CrossTenant-Id: 3dd8961f-e488-4e60-8e11-a82d994e183d X-MS-Exchange-CrossTenant-OriginalAttributedTenantConnectingIp: TenantId=3dd8961f-e488-4e60-8e11-a82d994e183d; Ip=[165.204.84.17]; Helo=[SATLEXMB04.amd.com] X-MS-Exchange-CrossTenant-AuthSource: CO1PEPF000042AB.namprd03.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Anonymous X-MS-Exchange-CrossTenant-FromEntityHeader: HybridOnPrem X-MS-Exchange-Transport-CrossTenantHeadersStamped: DM4PR12MB5937 Precedence: bulk List-ID: X-Mailing-List: linux-kselftest@vger.kernel.org Add support for getting the highest performance to the generic CPPC driver. This enables downstream drivers such as amd-pstate to discover and use these values. Please refer to the ACPI_Spec for details on continuous performance control of CPPC. Tested-by: Oleksandr Natalenko Reviewed-by: Mario Limonciello Reviewed-by: Wyes Karny Acked-by: Huang Rui Signed-off-by: Meng Li Link: https://uefi.org/specs/ACPI/6.5/08_Processor_Configuration_and_Control.html?highlight=cppc#highest-performance --- drivers/acpi/cppc_acpi.c | 13 +++++++++++++ include/acpi/cppc_acpi.h | 5 +++++ 2 files changed, 18 insertions(+) diff --git a/drivers/acpi/cppc_acpi.c b/drivers/acpi/cppc_acpi.c index 7ff269a78c20..ad388a0e8484 100644 --- a/drivers/acpi/cppc_acpi.c +++ b/drivers/acpi/cppc_acpi.c @@ -1154,6 +1154,19 @@ int cppc_get_nominal_perf(int cpunum, u64 *nominal_perf) return cppc_get_perf(cpunum, NOMINAL_PERF, nominal_perf); } +/** + * cppc_get_highest_perf - Get the highest performance register value. + * @cpunum: CPU from which to get highest performance. + * @highest_perf: Return address. + * + * Return: 0 for success, -EIO otherwise. + */ +int cppc_get_highest_perf(int cpunum, u64 *highest_perf) +{ + return cppc_get_perf(cpunum, HIGHEST_PERF, highest_perf); +} +EXPORT_SYMBOL_GPL(cppc_get_highest_perf); + /** * cppc_get_epp_perf - Get the epp register value. * @cpunum: CPU from which to get epp preference value. diff --git a/include/acpi/cppc_acpi.h b/include/acpi/cppc_acpi.h index 6126c977ece0..c0b69ffe7bdb 100644 --- a/include/acpi/cppc_acpi.h +++ b/include/acpi/cppc_acpi.h @@ -139,6 +139,7 @@ struct cppc_cpudata { #ifdef CONFIG_ACPI_CPPC_LIB extern int cppc_get_desired_perf(int cpunum, u64 *desired_perf); extern int cppc_get_nominal_perf(int cpunum, u64 *nominal_perf); +extern int cppc_get_highest_perf(int cpunum, u64 *highest_perf); extern int cppc_get_perf_ctrs(int cpu, struct cppc_perf_fb_ctrs *perf_fb_ctrs); extern int cppc_set_perf(int cpu, struct cppc_perf_ctrls *perf_ctrls); extern int cppc_set_enable(int cpu, bool enable); @@ -165,6 +166,10 @@ static inline int cppc_get_nominal_perf(int cpunum, u64 *nominal_perf) { return -ENOTSUPP; } +static inline int cppc_get_highest_perf(int cpunum, u64 *highest_perf) +{ + return -ENOTSUPP; +} static inline int cppc_get_perf_ctrs(int cpu, struct cppc_perf_fb_ctrs *perf_fb_ctrs) { return -ENOTSUPP; From patchwork Fri Oct 13 03:31:16 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Meng, Li \(Jassmine\)" X-Patchwork-Id: 733802 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 69F3FCDB474 for ; Fri, 13 Oct 2023 03:32:38 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229602AbjJMDcg (ORCPT ); Thu, 12 Oct 2023 23:32:36 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:52986 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229669AbjJMDca (ORCPT ); Thu, 12 Oct 2023 23:32:30 -0400 Received: from NAM04-DM6-obe.outbound.protection.outlook.com (mail-dm6nam04on2056.outbound.protection.outlook.com [40.107.102.56]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 98EEEDE; 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Wysocki" , Huang Rui CC: , , , , Shuah Khan , , "Nathan Fontenot" , Deepak Sharma , Alex Deucher , Mario Limonciello , Shimmer Huang , "Perry Yuan" , Xiaojian Du , Viresh Kumar , Borislav Petkov , "Oleksandr Natalenko" , Meng Li , Wyes Karny Subject: [RESEND PATCH V9 5/7] cpufreq: amd-pstate: Update amd-pstate preferred core ranking dynamically Date: Fri, 13 Oct 2023 11:31:16 +0800 Message-ID: <20231013033118.3759311-6-li.meng@amd.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20231013033118.3759311-1-li.meng@amd.com> References: <20231013033118.3759311-1-li.meng@amd.com> MIME-Version: 1.0 X-Originating-IP: [10.180.168.240] X-ClientProxiedBy: SATLEXMB03.amd.com (10.181.40.144) To SATLEXMB04.amd.com (10.181.40.145) X-EOPAttributedMessage: 0 X-MS-PublicTrafficType: Email X-MS-TrafficTypeDiagnostic: CO1PEPF000042AB:EE_|SJ2PR12MB8876:EE_ X-MS-Office365-Filtering-Correlation-Id: 6b60f3d3-bcbd-4af5-bf3f-08dbcb9d0279 X-MS-Exchange-SenderADCheck: 1 X-MS-Exchange-AntiSpam-Relay: 0 X-Microsoft-Antispam: BCL:0; X-Microsoft-Antispam-Message-Info: 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 X-Forefront-Antispam-Report: CIP:165.204.84.17; CTRY:US; LANG:en; SCL:1; SRV:; IPV:CAL; SFV:NSPM; H:SATLEXMB04.amd.com; PTR:InfoDomainNonexistent; CAT:NONE; SFS:(13230031)(4636009)(396003)(346002)(136003)(39860400002)(376002)(230922051799003)(186009)(1800799009)(82310400011)(64100799003)(451199024)(36840700001)(46966006)(40470700004)(7696005)(8936002)(8676002)(478600001)(5660300002)(41300700001)(26005)(336012)(1076003)(426003)(16526019)(2616005)(4326008)(70586007)(6636002)(316002)(54906003)(70206006)(110136005)(15650500001)(40460700003)(47076005)(36860700001)(66899024)(83380400001)(82740400003)(2906002)(40480700001)(81166007)(356005)(7416002)(36756003)(86362001)(36900700001); DIR:OUT; SFP:1101; X-OriginatorOrg: amd.com X-MS-Exchange-CrossTenant-OriginalArrivalTime: 13 Oct 2023 03:32:21.3331 (UTC) X-MS-Exchange-CrossTenant-Network-Message-Id: 6b60f3d3-bcbd-4af5-bf3f-08dbcb9d0279 X-MS-Exchange-CrossTenant-Id: 3dd8961f-e488-4e60-8e11-a82d994e183d X-MS-Exchange-CrossTenant-OriginalAttributedTenantConnectingIp: TenantId=3dd8961f-e488-4e60-8e11-a82d994e183d; Ip=[165.204.84.17]; Helo=[SATLEXMB04.amd.com] X-MS-Exchange-CrossTenant-AuthSource: CO1PEPF000042AB.namprd03.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Anonymous X-MS-Exchange-CrossTenant-FromEntityHeader: HybridOnPrem X-MS-Exchange-Transport-CrossTenantHeadersStamped: SJ2PR12MB8876 Precedence: bulk List-ID: X-Mailing-List: linux-kselftest@vger.kernel.org Preferred core rankings can be changed dynamically by the platform based on the workload and platform conditions and accounting for thermals and aging. When this occurs, cpu priority need to be set. Tested-by: Oleksandr Natalenko Reviewed-by: Mario Limonciello Reviewed-by: Wyes Karny Reviewed-by: Huang Rui Signed-off-by: Meng Li --- drivers/cpufreq/amd-pstate.c | 49 ++++++++++++++++++++++++++++++++++++ include/linux/amd-pstate.h | 6 +++++ 2 files changed, 55 insertions(+) diff --git a/drivers/cpufreq/amd-pstate.c b/drivers/cpufreq/amd-pstate.c index 6aae383990f1..3b054e3acba1 100644 --- a/drivers/cpufreq/amd-pstate.c +++ b/drivers/cpufreq/amd-pstate.c @@ -313,6 +313,7 @@ static int pstate_init_perf(struct amd_cpudata *cpudata) WRITE_ONCE(cpudata->nominal_perf, AMD_CPPC_NOMINAL_PERF(cap1)); WRITE_ONCE(cpudata->lowest_nonlinear_perf, AMD_CPPC_LOWNONLIN_PERF(cap1)); WRITE_ONCE(cpudata->lowest_perf, AMD_CPPC_LOWEST_PERF(cap1)); + WRITE_ONCE(cpudata->prefcore_ranking, AMD_CPPC_HIGHEST_PERF(cap1)); return 0; } @@ -334,6 +335,7 @@ static int cppc_init_perf(struct amd_cpudata *cpudata) WRITE_ONCE(cpudata->lowest_nonlinear_perf, cppc_perf.lowest_nonlinear_perf); WRITE_ONCE(cpudata->lowest_perf, cppc_perf.lowest_perf); + WRITE_ONCE(cpudata->prefcore_ranking, cppc_perf.highest_perf); if (cppc_state == AMD_PSTATE_ACTIVE) return 0; @@ -763,6 +765,37 @@ static void amd_pstate_init_prefcore(struct amd_cpudata *cpudata) } } +static void amd_pstate_update_highest_perf(unsigned int cpu) +{ + struct cpufreq_policy *policy; + struct amd_cpudata *cpudata; + u32 prev_high = 0, cur_high = 0; + int ret; + + if ((!amd_pstate_prefcore) || (!cpudata->hw_prefcore)) + return; + + ret = amd_pstate_get_highest_perf(cpu, &cur_high); + if (ret) + return; + + policy = cpufreq_cpu_get(cpu); + cpudata = policy->driver_data; + prev_high = READ_ONCE(cpudata->prefcore_ranking); + + if (prev_high != cur_high) { + int prio; + + WRITE_ONCE(cpudata->prefcore_ranking, cur_high); + + /* The maximum value of highest perf is 255 */ + prio = (int)(cur_high & 0xff); + sched_set_itmt_core_prio(prio, cpu); + } + + cpufreq_cpu_put(policy); +} + static int amd_pstate_cpu_init(struct cpufreq_policy *policy) { int min_freq, max_freq, nominal_freq, lowest_nonlinear_freq, ret; @@ -934,6 +967,17 @@ static ssize_t show_amd_pstate_highest_perf(struct cpufreq_policy *policy, return sysfs_emit(buf, "%u\n", perf); } +static ssize_t show_amd_pstate_prefcore_ranking(struct cpufreq_policy *policy, + char *buf) +{ + u32 perf; + struct amd_cpudata *cpudata = policy->driver_data; + + perf = READ_ONCE(cpudata->prefcore_ranking); + + return sysfs_emit(buf, "%u\n", perf); +} + static ssize_t show_amd_pstate_hw_prefcore(struct cpufreq_policy *policy, char *buf) { @@ -1147,6 +1191,7 @@ cpufreq_freq_attr_ro(amd_pstate_max_freq); cpufreq_freq_attr_ro(amd_pstate_lowest_nonlinear_freq); cpufreq_freq_attr_ro(amd_pstate_highest_perf); +cpufreq_freq_attr_ro(amd_pstate_prefcore_ranking); cpufreq_freq_attr_ro(amd_pstate_hw_prefcore); cpufreq_freq_attr_rw(energy_performance_preference); cpufreq_freq_attr_ro(energy_performance_available_preferences); @@ -1157,6 +1202,7 @@ static struct freq_attr *amd_pstate_attr[] = { &amd_pstate_max_freq, &amd_pstate_lowest_nonlinear_freq, &amd_pstate_highest_perf, + &amd_pstate_prefcore_ranking, &amd_pstate_hw_prefcore, NULL, }; @@ -1165,6 +1211,7 @@ static struct freq_attr *amd_pstate_epp_attr[] = { &amd_pstate_max_freq, &amd_pstate_lowest_nonlinear_freq, &amd_pstate_highest_perf, + &amd_pstate_prefcore_ranking, &amd_pstate_hw_prefcore, &energy_performance_preference, &energy_performance_available_preferences, @@ -1505,6 +1552,7 @@ static struct cpufreq_driver amd_pstate_driver = { .suspend = amd_pstate_cpu_suspend, .resume = amd_pstate_cpu_resume, .set_boost = amd_pstate_set_boost, + .update_highest_perf = amd_pstate_update_highest_perf, .name = "amd-pstate", .attr = amd_pstate_attr, }; @@ -1519,6 +1567,7 @@ static struct cpufreq_driver amd_pstate_epp_driver = { .online = amd_pstate_epp_cpu_online, .suspend = amd_pstate_epp_suspend, .resume = amd_pstate_epp_resume, + .update_highest_perf = amd_pstate_update_highest_perf, .name = "amd-pstate-epp", .attr = amd_pstate_epp_attr, }; diff --git a/include/linux/amd-pstate.h b/include/linux/amd-pstate.h index 87e140e9e6db..426822612373 100644 --- a/include/linux/amd-pstate.h +++ b/include/linux/amd-pstate.h @@ -39,11 +39,16 @@ struct amd_aperf_mperf { * @cppc_req_cached: cached performance request hints * @highest_perf: the maximum performance an individual processor may reach, * assuming ideal conditions + * For platforms that do not support the preferred core feature, the + * highest_pef may be configured with 166 or 255, to avoid max frequency + * calculated wrongly. we take the fixed value as the highest_perf. * @nominal_perf: the maximum sustained performance level of the processor, * assuming ideal operating conditions * @lowest_nonlinear_perf: the lowest performance level at which nonlinear power * savings are achieved * @lowest_perf: the absolute lowest performance level of the processor + * @prefcore_ranking: the preferred core ranking, the higher value indicates a higher + * priority. * @max_freq: the frequency that mapped to highest_perf * @min_freq: the frequency that mapped to lowest_perf * @nominal_freq: the frequency that mapped to nominal_perf @@ -73,6 +78,7 @@ struct amd_cpudata { u32 nominal_perf; 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Wysocki" , Huang Rui CC: , , , , Shuah Khan , , "Nathan Fontenot" , Deepak Sharma , Alex Deucher , Mario Limonciello , Shimmer Huang , "Perry Yuan" , Xiaojian Du , Viresh Kumar , Borislav Petkov , "Oleksandr Natalenko" , Meng Li , Wyes Karny Subject: [RESEND PATCH V9 6/7] Documentation: amd-pstate: introduce amd-pstate preferred core Date: Fri, 13 Oct 2023 11:31:17 +0800 Message-ID: <20231013033118.3759311-7-li.meng@amd.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20231013033118.3759311-1-li.meng@amd.com> References: <20231013033118.3759311-1-li.meng@amd.com> MIME-Version: 1.0 X-Originating-IP: [10.180.168.240] X-ClientProxiedBy: SATLEXMB03.amd.com (10.181.40.144) To SATLEXMB04.amd.com (10.181.40.145) X-EOPAttributedMessage: 0 X-MS-PublicTrafficType: Email X-MS-TrafficTypeDiagnostic: CO1PEPF000042AA:EE_|IA1PR12MB6211:EE_ X-MS-Office365-Filtering-Correlation-Id: 22dd36ee-65e2-4c52-4ac5-08dbcb9d054d X-MS-Exchange-SenderADCheck: 1 X-MS-Exchange-AntiSpam-Relay: 0 X-Microsoft-Antispam: BCL:0; X-Microsoft-Antispam-Message-Info: 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 X-Forefront-Antispam-Report: CIP:165.204.84.17; CTRY:US; LANG:en; SCL:1; SRV:; IPV:CAL; SFV:NSPM; H:SATLEXMB04.amd.com; PTR:InfoDomainNonexistent; CAT:NONE; SFS:(13230031)(4636009)(39860400002)(376002)(346002)(136003)(396003)(230922051799003)(64100799003)(451199024)(186009)(82310400011)(1800799009)(36840700001)(46966006)(40470700004)(83380400001)(7416002)(36860700001)(2906002)(40460700003)(47076005)(36756003)(86362001)(40480700001)(82740400003)(81166007)(356005)(6636002)(70586007)(110136005)(54906003)(41300700001)(1076003)(2616005)(26005)(16526019)(6666004)(316002)(70206006)(7696005)(478600001)(5660300002)(336012)(426003)(4326008)(8936002)(8676002)(36900700001); DIR:OUT; SFP:1101; X-OriginatorOrg: amd.com X-MS-Exchange-CrossTenant-OriginalArrivalTime: 13 Oct 2023 03:32:26.0750 (UTC) X-MS-Exchange-CrossTenant-Network-Message-Id: 22dd36ee-65e2-4c52-4ac5-08dbcb9d054d X-MS-Exchange-CrossTenant-Id: 3dd8961f-e488-4e60-8e11-a82d994e183d X-MS-Exchange-CrossTenant-OriginalAttributedTenantConnectingIp: TenantId=3dd8961f-e488-4e60-8e11-a82d994e183d; Ip=[165.204.84.17]; Helo=[SATLEXMB04.amd.com] X-MS-Exchange-CrossTenant-AuthSource: CO1PEPF000042AA.namprd03.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Anonymous X-MS-Exchange-CrossTenant-FromEntityHeader: HybridOnPrem X-MS-Exchange-Transport-CrossTenantHeadersStamped: IA1PR12MB6211 Precedence: bulk List-ID: X-Mailing-List: linux-kselftest@vger.kernel.org Introduce amd-pstate preferred core. check preferred core state set by the kernel parameter: $ cat /sys/devices/system/cpu/amd-pstate/prefcore Tested-by: Oleksandr Natalenko Reviewed-by: Wyes Karny Reviewed-by: Mario Limonciello Reviewed-by: Huang Rui Signed-off-by: Meng Li --- Documentation/admin-guide/pm/amd-pstate.rst | 59 ++++++++++++++++++++- 1 file changed, 57 insertions(+), 2 deletions(-) diff --git a/Documentation/admin-guide/pm/amd-pstate.rst b/Documentation/admin-guide/pm/amd-pstate.rst index 1cf40f69278c..0b832ff529db 100644 --- a/Documentation/admin-guide/pm/amd-pstate.rst +++ b/Documentation/admin-guide/pm/amd-pstate.rst @@ -300,8 +300,8 @@ platforms. The AMD P-States mechanism is the more performance and energy efficiency frequency management method on AMD processors. -AMD Pstate Driver Operation Modes -================================= +``amd-pstate`` Driver Operation Modes +====================================== ``amd_pstate`` CPPC has 3 operation modes: autonomous (active) mode, non-autonomous (passive) mode and guided autonomous (guided) mode. @@ -353,6 +353,48 @@ is activated. In this mode, driver requests minimum and maximum performance level and the platform autonomously selects a performance level in this range and appropriate to the current workload. +``amd-pstate`` Preferred Core +================================= + +The core frequency is subjected to the process variation in semiconductors. +Not all cores are able to reach the maximum frequency respecting the +infrastructure limits. Consequently, AMD has redefined the concept of +maximum frequency of a part. This means that a fraction of cores can reach +maximum frequency. To find the best process scheduling policy for a given +scenario, OS needs to know the core ordering informed by the platform through +highest performance capability register of the CPPC interface. + +``amd-pstate`` preferred core enables the scheduler to prefer scheduling on +cores that can achieve a higher frequency with lower voltage. The preferred +core rankings can dynamically change based on the workload, platform conditions, +thermals and ageing. + +The priority metric will be initialized by the ``amd-pstate`` driver. The ``amd-pstate`` +driver will also determine whether or not ``amd-pstate`` preferred core is +supported by the platform. + +``amd-pstate`` driver will provide an initial core ordering when the system boots. +The platform uses the CPPC interfaces to communicate the core ranking to the +operating system and scheduler to make sure that OS is choosing the cores +with highest performance firstly for scheduling the process. When ``amd-pstate`` +driver receives a message with the highest performance change, it will +update the core ranking and set the cpu's priority. + +``amd-pstate`` Preferred Core Switch +================================= +Kernel Parameters +----------------- + +``amd-pstate`` peferred core`` has two states: enable and disable. +Enable/disable states can be chosen by different kernel parameters. +Default enable ``amd-pstate`` preferred core. + +``amd_prefcore=disable`` + +For systems that support ``amd-pstate`` preferred core, the core rankings will +always be advertised by the platform. But OS can choose to ignore that via the +kernel parameter ``amd_prefcore=disable``. + User Space Interface in ``sysfs`` - General =========================================== @@ -385,6 +427,19 @@ control its functionality at the system level. They are located in the to the operation mode represented by that string - or to be unregistered in the "disable" case. +``prefcore`` + Preferred core state of the driver: "enabled" or "disabled". + + "enabled" + Enable the ``amd-pstate`` preferred core. + + "disabled" + Disable the ``amd-pstate`` preferred core + + + This attribute is read-only to check the state of preferred core set + by the kernel parameter. + ``cpupower`` tool support for ``amd-pstate`` ===============================================