/* * Copyright (C) 2011 Google, Inc. * * Author: * Colin Cross * * This software is licensed under the terms of the GNU General Public * License version 2, as published by the Free Software Foundation, and * may be copied, distributed, and modified under those terms. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * */ #include #include #include #include #include #include static DEFINE_RWLOCK(cpu_pm_notifier_lock); static RAW_NOTIFIER_HEAD(cpu_pm_notifier_chain); static int cpu_pm_notify(enum cpu_pm_event event, int nr_to_call, int *nr_calls) { int ret; ret = __raw_notifier_call_chain(&cpu_pm_notifier_chain, event, NULL, nr_to_call, nr_calls); return notifier_to_errno(ret); } /** * cpu_pm_register_notifier - register a driver with cpu_pm * @nb: notifier block to register * * Add a driver to a list of drivers that are notified about * CPU and CPU cluster low power entry and exit. * * This function may sleep, and has the same return conditions as * raw_notifier_chain_register. */ int cpu_pm_register_notifier(struct notifier_block *nb) { unsigned long flags; int ret; write_lock_irqsave(&cpu_pm_notifier_lock, flags); ret = raw_notifier_chain_register(&cpu_pm_notifier_chain, nb); write_unlock_irqrestore(&cpu_pm_notifier_lock, flags); return ret; } EXPORT_SYMBOL_GPL(cpu_pm_register_notifier); /** * cpu_pm_unregister_notifier - unregister a driver with cpu_pm * @nb: notifier block to be unregistered * * Remove a driver from the CPU PM notifier list. * * This function may sleep, and has the same return conditions as * raw_notifier_chain_unregister. */ int cpu_pm_unregister_notifier(struct notifier_block *nb) { unsigned long flags; int ret; write_lock_irqsave(&cpu_pm_notifier_lock, flags); ret = raw_notifier_chain_unregister(&cpu_pm_notifier_chain, nb); write_unlock_irqrestore(&cpu_pm_notifier_lock, flags); return ret; } EXPORT_SYMBOL_GPL(cpu_pm_unregister_notifier); /** * cpu_pm_enter - CPU low power entry notifier * * Notifies listeners that a single CPU is entering a low power state that may * cause some blocks in the same power domain as the cpu to reset. * * Must be called on the affected CPU with interrupts disabled. Platform is * responsible for ensuring that cpu_pm_enter is not called twice on the same * CPU before cpu_pm_exit is called. Notified drivers can include VFP * co-processor, interrupt controller and its PM extensions, local CPU * timers context save/restore which shouldn't be interrupted. Hence it * must be called with interrupts disabled. * * Return conditions are same as __raw_notifier_call_chain. */ int cpu_pm_enter(void) { int nr_calls; int ret = 0; read_lock(&cpu_pm_notifier_lock); ret = cpu_pm_notify(CPU_PM_ENTER, -1, &nr_calls); if (ret) /* * Inform listeners (nr_calls - 1) about failure of CPU PM * PM entry who are notified earlier to prepare for it. */ cpu_pm_notify(CPU_PM_ENTER_FAILED, nr_calls - 1, NULL); read_unlock(&cpu_pm_notifier_lock); return ret; } EXPORT_SYMBOL_GPL(cpu_pm_enter); /** * cpu_pm_exit - CPU low power exit notifier * * Notifies listeners that a single CPU is exiting a low power state that may * have caused some blocks in the same power domain as the cpu to reset. * * Notified drivers can include VFP co-processor, interrupt controller * and its PM extensions, local CPU timers context save/restore which * shouldn't be interrupted. Hence it must be called with interrupts disabled. * * Return conditions are same as __raw_notifier_call_chain. */ int cpu_pm_exit(void) { int ret; read_lock(&cpu_pm_notifier_lock); ret = cpu_pm_notify(CPU_PM_EXIT, -1, NULL); read_unlock(&cpu_pm_notifier_lock); return ret; } EXPORT_SYMBOL_GPL(cpu_pm_exit); /** * cpu_cluster_pm_enter - CPU cluster low power entry notifier * * Notifies listeners that all cpus in a power domain are entering a low power * state that may cause some blocks in the same power domain to reset. * * Must be called after cpu_pm_enter has been called on all cpus in the power * domain, and before cpu_pm_exit has been called on any cpu in the power * domain. Notified drivers can include VFP co-processor, interrupt controller * and its PM extensions, local CPU timers context save/restore which * shouldn't be interrupted. Hence it must be called with interrupts disabled. * * Must be called with interrupts disabled. * * Return conditions are same as __raw_notifier_call_chain. */ int cpu_cluster_pm_enter(void) { int nr_calls; int ret = 0; read_lock(&cpu_pm_notifier_lock); ret = cpu_pm_notify(CPU_CLUSTER_PM_ENTER, -1, &nr_calls); if (ret) /* * Inform listeners (nr_calls - 1) about failure of CPU cluster * PM entry who are notified earlier to prepare for it. */ cpu_pm_notify(CPU_CLUSTER_PM_ENTER_FAILED, nr_calls - 1, NULL); read_unlock(&cpu_pm_notifier_lock); return ret; } EXPORT_SYMBOL_GPL(cpu_cluster_pm_enter); /** * cpu_cluster_pm_exit - CPU cluster low power exit notifier * * Notifies listeners that all cpus in a power domain are exiting form a * low power state that may have caused some blocks in the same power domain * to reset. * * Must be called after cpu_cluster_pm_enter has been called for the power * domain, and before cpu_pm_exit has been called on any cpu in the power * domain. Notified drivers can include VFP co-processor, interrupt controller * and its PM extensions, local CPU timers context save/restore which * shouldn't be interrupted. Hence it must be called with interrupts disabled. * * Return conditions are same as __raw_notifier_call_chain. */ int cpu_cluster_pm_exit(void) { int ret; read_lock(&cpu_pm_notifier_lock); ret = cpu_pm_notify(CPU_CLUSTER_PM_EXIT, -1, NULL); read_unlock(&cpu_pm_notifier_lock); return ret; } EXPORT_SYMBOL_GPL(cpu_cluster_pm_exit); #ifdef CONFIG_PM static int cpu_pm_suspend(void) { int ret; ret = cpu_pm_enter(); if (ret) return ret; ret = cpu_cluster_pm_enter(); return ret; } static void cpu_pm_resume(void) { cpu_cluster_pm_exit(); cpu_pm_exit(); } static struct syscore_ops cpu_pm_syscore_ops = { .suspend = cpu_pm_suspend, .resume = cpu_pm_resume, }; static int cpu_pm_init(void) { register_syscore_ops(&cpu_pm_syscore_ops); return 0; } core_initcall(cpu_pm_init); #endif TL BIT-EE, which is not recommended to be enabled on this SKU. On the failing systems, this BIOS issue was not discovered when the desktop motherboard was tested with Windows, because the BIOS also neglects to provide the ACPI/CPPC table, that Windows requires to enable HWP, and so Windows runs in legacy P-state mode, where this setting has no effect. Linux' intel_pstate driver does not require ACPI/CPPC to enable HWP, and so it runs in HWP mode, exposing this incorrect BIOS configuration. There are several ways to address this problem. First, Linux can also run in legacy P-state mode on this system. As intel_pstate is how Linux enables HWP, booting with "intel_pstate=disable" will run in acpi-cpufreq/ondemand legacy p-state mode. Or second, the "performance" governor can be used with intel_pstate, which will modify HWP.EPP to 0. Or third, starting in 4.10, the /sys/devices/system/cpu/cpufreq/policy*/energy_performance_preference attribute in can be updated from "balance_power" to "performance". Or fourth, apply this patch, which fixes the erroneous setting of MSR_IA32_POWER_CTL BIT_EE on this model, allowing the default configuration to function as designed. Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com> Reviewed-by: Len Brown <len.brown@intel.com> Cc: 4.6+ <stable@vger.kernel.org> # 4.6+ Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Diffstat (limited to 'include/trace/events/sunrpc.h')