Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754168AbbGPSRN (ORCPT ); Thu, 16 Jul 2015 14:17:13 -0400 Received: from forward-corp1f.mail.yandex.net ([95.108.130.40]:50214 "EHLO forward-corp1f.mail.yandex.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751434AbbGPSRM (ORCPT ); Thu, 16 Jul 2015 14:17:12 -0400 Authentication-Results: smtpcorp4.mail.yandex.net; dkim=pass header.i=@yandex-team.ru Subject: [PATCH RFC] intel_pstate: play well with frequency limits set by acpi From: Konstantin Khlebnikov To: linux-pm@vger.kernel.org, "Rafael J. Wysocki" , linux-kernel@vger.kernel.org, linux-acpi@vger.kernel.org, Kristen Carlson Accardi , Len Brown Cc: Ethan Zhao Date: Thu, 16 Jul 2015 21:17:06 +0300 Message-ID: <20150716181706.6500.64386.stgit@buzz> User-Agent: StGit/0.17.1-dirty MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 4905 Lines: 159 IPMI can control CPU P-states remotely: configuration is reported via common ACPI interface (_PPC/_PSS/etc). This patch adds required minimal support in intel_pstate to receive and use these P-state limits. * ignore limit of top state in _PPC: it lower than turbo boost frequency * register intel_pstate in acpi-processor to get states from _PSS * link acpi_processor_get_bios_limit: this adds attribute "bios_limit" Signed-off-by: Konstantin Khlebnikov --- drivers/acpi/processor_perflib.c | 3 +- drivers/cpufreq/intel_pstate.c | 57 ++++++++++++++++++++++++++++++++++++++ 2 files changed, 59 insertions(+), 1 deletion(-) diff --git a/drivers/acpi/processor_perflib.c b/drivers/acpi/processor_perflib.c index cfc8aba72f86..781e328c9d5f 100644 --- a/drivers/acpi/processor_perflib.c +++ b/drivers/acpi/processor_perflib.c @@ -98,7 +98,8 @@ static int acpi_processor_ppc_notifier(struct notifier_block *nb, ppc = (unsigned int)pr->performance_platform_limit; - if (ppc >= pr->performance->state_count) + /* Ignore limit of top state: it lower than turbo boost frequency */ + if (!ppc || ppc >= pr->performance->state_count) goto out; cpufreq_verify_within_limits(policy, 0, diff --git a/drivers/cpufreq/intel_pstate.c b/drivers/cpufreq/intel_pstate.c index 15ada47bb720..4a34ddf4fa73 100644 --- a/drivers/cpufreq/intel_pstate.c +++ b/drivers/cpufreq/intel_pstate.c @@ -26,6 +26,7 @@ #include #include #include +#include #include #include @@ -113,6 +114,9 @@ struct cpudata { u64 prev_mperf; u64 prev_tsc; struct sample sample; +#ifdef CONFIG_ACPI_PROCESSOR + struct acpi_processor_performance acpi_data; +#endif }; static struct cpudata **all_cpu_data; @@ -145,6 +149,7 @@ static int hwp_active; struct perf_limits { int no_turbo; + int no_acpi; int turbo_disabled; int max_perf_pct; int min_perf_pct; @@ -158,6 +163,7 @@ struct perf_limits { static struct perf_limits limits = { .no_turbo = 0, + .no_acpi = !IS_ENABLED(CONFIG_ACPI_PROCESSOR), .turbo_disabled = 0, .max_perf_pct = 100, .max_perf = int_tofp(1), @@ -449,6 +455,18 @@ static ssize_t store_min_perf_pct(struct kobject *a, struct attribute *b, return count; } +static ssize_t store_no_acpi(struct kobject *a, struct attribute *b, + const char *buf, size_t count) +{ +#ifdef CONFIG_ACPI_PROCESSOR + return kstrtouint(buf, 0, &limits.no_acpi) ?: count; +#else + return -ENODEV; +#endif +} +show_one(no_acpi, no_acpi); +define_one_global_rw(no_acpi); + show_one(max_perf_pct, max_perf_pct); show_one(min_perf_pct, min_perf_pct); @@ -460,6 +478,7 @@ define_one_global_ro(num_pstates); static struct attribute *intel_pstate_attributes[] = { &no_turbo.attr, + &no_acpi.attr, &max_perf_pct.attr, &min_perf_pct.attr, &turbo_pct.attr, @@ -1049,6 +1068,38 @@ static int intel_pstate_cpu_init(struct cpufreq_policy *policy) policy->cpuinfo.transition_latency = CPUFREQ_ETERNAL; cpumask_set_cpu(policy->cpu, policy->cpus); +#ifdef CONFIG_ACPI_PROCESSOR + if (!limits.no_acpi) { + /* + * Minimum necessary to get acpi_processor_ppc_notifier() and + * acpi_processor_get_bios_limit() working. + */ + if (!zalloc_cpumask_var(&cpu->acpi_data.shared_cpu_map, + GFP_KERNEL)) + rc = -ENOMEM; + else + rc = acpi_processor_register_performance( + &cpu->acpi_data, policy->cpu); + if (rc) { + pr_err("intel_pstate: acpi init failed: %d\n", rc); + free_cpumask_var(cpu->acpi_data.shared_cpu_map); + limits.no_acpi = 1; + } + } +#endif + return 0; +} + +static int intel_pstate_cpu_exit(struct cpufreq_policy *policy) +{ +#ifdef CONFIG_ACPI_PROCESSOR + struct cpudata *cpu = all_cpu_data[policy->cpu]; + + if (cpu->acpi_data.state_count) + acpi_processor_unregister_performance(&cpu->acpi_data, + policy->cpu); + free_cpumask_var(cpu->acpi_data.shared_cpu_map); +#endif return 0; } @@ -1057,7 +1108,11 @@ static struct cpufreq_driver intel_pstate_driver = { .verify = intel_pstate_verify_policy, .setpolicy = intel_pstate_set_policy, .get = intel_pstate_get, +#ifdef CONFIG_ACPI_PROCESSOR + .bios_limit = acpi_processor_get_bios_limit, +#endif .init = intel_pstate_cpu_init, + .exit = intel_pstate_cpu_exit, .stop_cpu = intel_pstate_stop_cpu, .name = "intel_pstate", }; @@ -1286,6 +1341,8 @@ static int __init intel_pstate_setup(char *str) force_load = 1; if (!strcmp(str, "hwp_only")) hwp_only = 1; + if (!strcmp(str, "no_acpi")) + limits.no_acpi = 1; return 0; } early_param("intel_pstate", intel_pstate_setup); -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/