/* * processor_perflib.c - ACPI Processor P-States Library ($Revision: 71 $) * * Copyright (C) 2001, 2002 Andy Grover <andrew.grover@intel.com> * Copyright (C) 2001, 2002 Paul Diefenbaugh <paul.s.diefenbaugh@intel.com> * Copyright (C) 2004 Dominik Brodowski <linux@brodo.de> * Copyright (C) 2004 Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com> * - Added processor hotplug support * * * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation; either version 2 of the License, or (at * your option) any later version. * * 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. * * You should have received a copy of the GNU General Public License along * with this program; if not, write to the Free Software Foundation, Inc., * 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA. * */ #include <linux/kernel.h> #include <linux/module.h> #include <linux/init.h> #include <linux/cpufreq.h> #ifdef CONFIG_X86_ACPI_CPUFREQ_PROC_INTF #include <linux/proc_fs.h> #include <linux/seq_file.h> #include <asm/uaccess.h> #endif #include <acpi/acpi_bus.h> #include <acpi/processor.h> #define ACPI_PROCESSOR_COMPONENT 0x01000000 #define ACPI_PROCESSOR_CLASS "processor" #define ACPI_PROCESSOR_DRIVER_NAME "ACPI Processor Driver" #define ACPI_PROCESSOR_FILE_PERFORMANCE "performance" #define _COMPONENT ACPI_PROCESSOR_COMPONENT ACPI_MODULE_NAME("acpi_processor") static DECLARE_MUTEX(performance_sem); /* * _PPC support is implemented as a CPUfreq policy notifier: * This means each time a CPUfreq driver registered also with * the ACPI core is asked to change the speed policy, the maximum * value is adjusted so that it is within the platform limit. * * Also, when a new platform limit value is detected, the CPUfreq * policy is adjusted accordingly. */ #define PPC_REGISTERED 1 #define PPC_IN_USE 2 static int acpi_processor_ppc_status = 0; static int acpi_processor_ppc_notifier(struct notifier_block *nb, unsigned long event, void *data) { struct cpufreq_policy *policy = data; struct acpi_processor *pr; unsigned int ppc = 0; down(&performance_sem); if (event != CPUFREQ_INCOMPATIBLE) goto out; pr = processors[policy->cpu]; if (!pr || !pr->performance) goto out; ppc = (unsigned int)pr->performance_platform_limit; if (!ppc) goto out; if (ppc > pr->performance->state_count) goto out; cpufreq_verify_within_limits(policy, 0, pr->performance->states[ppc]. core_frequency * 1000); out: up(&performance_sem); return 0; } static struct notifier_block acpi_ppc_notifier_block = { .notifier_call = acpi_processor_ppc_notifier, }; static int acpi_processor_get_platform_limit(struct acpi_processor *pr) { acpi_status status = 0; unsigned long ppc = 0; ACPI_FUNCTION_TRACE("acpi_processor_get_platform_limit"); if (!pr) return_VALUE(-EINVAL); /* * _PPC indicates the maximum state currently supported by the platform * (e.g. 0 = states 0..n; 1 = states 1..n; etc. */ status = acpi_evaluate_integer(pr->handle, "_PPC", NULL, &ppc); if (status != AE_NOT_FOUND) acpi_processor_ppc_status |= PPC_IN_USE; if (ACPI_FAILURE(status) && status != AE_NOT_FOUND) { ACPI_DEBUG_PRINT((ACPI_DB_ERROR, "Error evaluating _PPC\n")); return_VALUE(-ENODEV); } pr->performance_platform_limit = (int)ppc; return_VALUE(0); } int acpi_processor_ppc_has_changed(struct acpi_processor *pr) { int ret = acpi_processor_get_platform_limit(pr); if (ret < 0) return (ret); else return cpufreq_update_policy(pr->id); } void acpi_processor_ppc_init(void) { if (!cpufreq_register_notifier (&acpi_ppc_notifier_block, CPUFREQ_POLICY_NOTIFIER)) acpi_processor_ppc_status |= PPC_REGISTERED; else printk(KERN_DEBUG "Warning: Processor Platform Limit not supported.\n"); } void acpi_processor_ppc_exit(void) { if (acpi_processor_ppc_status & PPC_REGISTERED) cpufreq_unregister_notifier(&acpi_ppc_notifier_block, CPUFREQ_POLICY_NOTIFIER); acpi_processor_ppc_status &= ~PPC_REGISTERED; } static int acpi_processor_get_performance_control(struct acpi_processor *pr) { int result = 0; acpi_status status = 0; struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL }; union acpi_object *pct = NULL; union acpi_object obj = { 0 }; ACPI_FUNCTION_TRACE("acpi_processor_get_performance_control"); status = acpi_evaluate_object(pr->handle, "_PCT", NULL, &buffer); if (ACPI_FAILURE(status)) { ACPI_DEBUG_PRINT((ACPI_DB_ERROR, "Error evaluating _PCT\n")); return_VALUE(-ENODEV); } pct = (union acpi_object *)buffer.pointer; if (!pct || (pct->type != ACPI_TYPE_PACKAGE) || (pct->package.count != 2)) { ACPI_DEBUG_PRINT((ACPI_DB_ERROR, "Invalid _PCT data\n")); result = -EFAULT; goto end; } /* * control_register */ obj = pct->package.elements[0]; if ((obj.type != ACPI_TYPE_BUFFER) || (obj.buffer.length < sizeof(struct acpi_pct_register)) || (obj.buffer.pointer == NULL)) { ACPI_DEBUG_PRINT((ACPI_DB_ERROR, "Invalid _PCT data (control_register)\n")); result = -EFAULT; goto end; } memcpy(&pr->performance->control_register, obj.buffer.pointer, sizeof(struct acpi_pct_register)); /* * status_register */ obj = pct->package.elements[1]; if ((obj.type != ACPI_TYPE_BUFFER) || (obj.buffer.length < sizeof(struct acpi_pct_register)) || (obj.buffer.pointer == NULL)) { ACPI_DEBUG_PRINT((ACPI_DB_ERROR, "Invalid _PCT data (status_register)\n")); result = -EFAULT; goto end; } memcpy(&pr->performance->status_register, obj.buffer.pointer, sizeof(struct acpi_pct_register)); end: acpi_os_free(buffer.pointer); return_VALUE(result); } static int acpi_processor_get_performance_states(struct acpi_processor *pr) { int result = 0; acpi_status status = AE_OK; struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL }; struct acpi_buffer format = { sizeof("NNNNNN"), "NNNNNN" }; struct acpi_buffer state = { 0, NULL }; union acpi_object *pss = NULL; int i; ACPI_FUNCTION_TRACE("acpi_processor_get_performance_states"); status = acpi_evaluate_object(pr->handle, "_PSS", NULL, &buffer); if (ACPI_FAILURE(status)) { ACPI_DEBUG_PRINT((ACPI_DB_ERROR, "Error evaluating _PSS\n")); return_VALUE(-ENODEV); } pss = (union acpi_object *)buffer.pointer; if (!pss || (pss->type != ACPI_TYPE_PACKAGE)) { ACPI_DEBUG_PRINT((ACPI_DB_ERROR, "Invalid _PSS data\n")); result = -EFAULT; goto end; } ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found %d performance states\n", pss->package.count)); pr->performance->state_count = pss->package.count; pr->performance->states = kmalloc(sizeof(struct acpi_processor_px) * pss->package.count, GFP_KERNEL); if (!pr->performance->states) { result = -ENOMEM; goto end; } for (i = 0; i < pr->performance->state_count; i++) { struct acpi_processor_px *px = &(pr->performance->states[i]); state.length = sizeof(struct acpi_processor_px); state.pointer = px; ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Extracting state %d\n", i)); status = acpi_extract_package(&(pss->package.elements[i]), &format, &state); if (ACPI_FAILURE(status)) { ACPI_DEBUG_PRINT((ACPI_DB_ERROR, "Invalid _PSS data\n")); result = -EFAULT; kfree(pr->performance->states); goto end; } ACPI_DEBUG_PRINT((ACPI_DB_INFO, "State [%d]: core_frequency[%d] power[%d] transition_latency[%d] bus_master_latency[%d] control[0x%x] status[0x%x]\n", i, (u32) px->core_frequency, (u32) px->power, (u32) px->transition_latency, (u32) px->bus_master_latency, (u32) px->control, (u32) px->status)); if (!px->core_frequency) { ACPI_DEBUG_PRINT((ACPI_DB_ERROR, "Invalid _PSS data: freq is zero\n")); result = -EFAULT; kfree(pr->performance->states); goto end; } } end: acpi_os_free(buffer.pointer); return_VALUE(result); } static int acpi_processor_get_performance_info(struct acpi_processor *pr) { int result = 0; acpi_status status = AE_OK; acpi_handle handle = NULL; ACPI_FUNCTION_TRACE("acpi_processor_get_performance_info"); if (!pr || !pr->performance || !pr->handle) return_VALUE(-EINVAL); acpi_processor_set_pdc(pr, pr->performance->pdc); status = acpi_get_handle(pr->handle, "_PCT", &handle); if (ACPI_FAILURE(status)) { ACPI_DEBUG_PRINT((ACPI_DB_INFO, "ACPI-based processor performance control unavailable\n")); return_VALUE(-ENODEV); } result = acpi_processor_get_performance_control(pr); if (result) return_VALUE(result); result = acpi_processor_get_performance_states(pr); if (result) return_VALUE(result); result = acpi_processor_get_platform_limit(pr); if (result) return_VALUE(result); return_VALUE(0); } int acpi_processor_notify_smm(struct module *calling_module) { acpi_status status; static int is_done = 0; ACPI_FUNCTION_TRACE("acpi_processor_notify_smm"); if (!(acpi_processor_ppc_status & PPC_REGISTERED)) return_VALUE(-EBUSY); if (!try_module_get(calling_module)) return_VALUE(-EINVAL); /* is_done is set to negative if an error occured, * and to postitive if _no_ error occured, but SMM * was already notified. This avoids double notification * which might lead to unexpected results... */ if (is_done > 0) { module_put(calling_module); return_VALUE(0); } else if (is_done < 0) { module_put(calling_module); return_VALUE(is_done); } is_done = -EIO; /* Can't write pstate_cnt to smi_cmd if either value is zero */ if ((!acpi_fadt.smi_cmd) || (!acpi_fadt.pstate_cnt)) { ACPI_DEBUG_PRINT((ACPI_DB_INFO, "No SMI port or pstate_cnt\n")); module_put(calling_module); return_VALUE(0); } ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Writing pstate_cnt [0x%x] to smi_cmd [0x%x]\n", acpi_fadt.pstate_cnt, acpi_fadt.smi_cmd)); /* FADT v1 doesn't support pstate_cnt, many BIOS vendors use * it anyway, so we need to support it... */ if (acpi_fadt_is_v1) { ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Using v1.0 FADT reserved value for pstate_cnt\n")); } status = acpi_os_write_port(acpi_fadt.smi_cmd, (u32) acpi_fadt.pstate_cnt, 8); if (ACPI_FAILURE(status)) { ACPI_DEBUG_PRINT((ACPI_DB_ERROR, "Failed to write pstate_cnt [0x%x] to " "smi_cmd [0x%x]\n", acpi_fadt.pstate_cnt, acpi_fadt.smi_cmd)); module_put(calling_module); return_VALUE(status); } /* Success. If there's no _PPC, we need to fear nothing, so * we can allow the cpufreq driver to be rmmod'ed. */ is_done = 1; if (!(acpi_processor_ppc_status & PPC_IN_USE)) module_put(calling_module); return_VALUE(0); } EXPORT_SYMBOL(acpi_processor_notify_smm); #ifdef CONFIG_X86_ACPI_CPUFREQ_PROC_INTF /* /proc/acpi/processor/../performance interface (DEPRECATED) */ static int acpi_processor_perf_open_fs(struct inode *inode, struct file *file); static struct file_operations acpi_processor_perf_fops = { .open = acpi_processor_perf_open_fs, .read = seq_read, .llseek = seq_lseek, .release = single_release, }; static int acpi_processor_perf_seq_show(struct seq_file *seq, void *offset) { struct acpi_processor *pr = (struct acpi_processor *)seq->private; int i; ACPI_FUNCTION_TRACE("acpi_processor_perf_seq_show"); if (!pr) goto end; if (!pr->performance) { seq_puts(seq, "<not supported>\n"); goto end; } seq_printf(seq, "state count: %d\n" "active state: P%d\n", pr->performance->state_count, pr->performance->state); seq_puts(seq, "states:\n"); for (i = 0; i < pr->performance->state_count; i++) seq_printf(seq, " %cP%d: %d MHz, %d mW, %d uS\n", (i == pr->performance->state ? '*' : ' '), i, (u32) pr->performance->states[i].core_frequency, (u32) pr->performance->states[i].power, (u32) pr->performance->states[i].transition_latency); end: return_VALUE(0); } static int acpi_processor_perf_open_fs(struct inode *inode, struct file *file) { return single_open(file, acpi_processor_perf_seq_show, PDE(inode)->data); } static ssize_t acpi_processor_write_performance(struct file *file, const char __user * buffer, size_t count, loff_t * data) { int result = 0; struct seq_file *m = (struct seq_file *)file->private_data; struct acpi_processor *pr = (struct acpi_processor *)m->private; struct acpi_processor_performance *perf; char state_string[12] = { '\0' }; unsigned int new_state = 0; struct cpufreq_policy policy; ACPI_FUNCTION_TRACE("acpi_processor_write_performance"); if (!pr || (count > sizeof(state_string) - 1)) return_VALUE(-EINVAL); perf = pr->performance; if (!perf) return_VALUE(-EINVAL); if (copy_from_user(state_string, buffer, count)) return_VALUE(-EFAULT); state_string[count] = '\0'; new_state = simple_strtoul(state_string, NULL, 0); if (new_state >= perf->state_count) return_VALUE(-EINVAL); cpufreq_get_policy(&policy, pr->id); policy.cpu = pr->id; policy.min = perf->states[new_state].core_frequency * 1000; policy.max = perf->states[new_state].core_frequency * 1000; result = cpufreq_set_policy(&policy); if (result) return_VALUE(result); return_VALUE(count); } static void acpi_cpufreq_add_file(struct acpi_processor *pr) { struct proc_dir_entry *entry = NULL; struct acpi_device *device = NULL; ACPI_FUNCTION_TRACE("acpi_cpufreq_addfile"); if (acpi_bus_get_device(pr->handle, &device)) return_VOID; /* add file 'performance' [R/W] */ entry = create_proc_entry(ACPI_PROCESSOR_FILE_PERFORMANCE, S_IFREG | S_IRUGO | S_IWUSR, acpi_device_dir(device)); if (!entry) ACPI_DEBUG_PRINT((ACPI_DB_ERROR, "Unable to create '%s' fs entry\n", ACPI_PROCESSOR_FILE_PERFORMANCE)); else { entry->proc_fops = &acpi_processor_perf_fops; entry->proc_fops->write = acpi_processor_write_performance; entry->data = acpi_driver_data(device); entry->owner = THIS_MODULE; } return_VOID; } static void acpi_cpufreq_remove_file(struct acpi_processor *pr) { struct acpi_device *device = NULL; ACPI_FUNCTION_TRACE("acpi_cpufreq_addfile"); if (acpi_bus_get_device(pr->handle, &device)) return_VOID; /* remove file 'performance' */ remove_proc_entry(ACPI_PROCESSOR_FILE_PERFORMANCE, acpi_device_dir(device)); return_VOID; } #else static void acpi_cpufreq_add_file(struct acpi_processor *pr) { return; } static void acpi_cpufreq_remove_file(struct acpi_processor *pr) { return; } #endif /* CONFIG_X86_ACPI_CPUFREQ_PROC_INTF */ int acpi_processor_register_performance(struct acpi_processor_performance *performance, unsigned int cpu) { struct acpi_processor *pr; ACPI_FUNCTION_TRACE("acpi_processor_register_performance"); if (!(acpi_processor_ppc_status & PPC_REGISTERED)) return_VALUE(-EINVAL); down(&performance_sem); pr = processors[cpu]; if (!pr) { up(&performance_sem); return_VALUE(-ENODEV); } if (pr->performance) { up(&performance_sem); return_VALUE(-EBUSY); } pr->performance = performance; if (acpi_processor_get_performance_info(pr)) { pr->performance = NULL; up(&performance_sem); return_VALUE(-EIO); } acpi_cpufreq_add_file(pr); up(&performance_sem); return_VALUE(0); } EXPORT_SYMBOL(acpi_processor_register_performance); void acpi_processor_unregister_performance(struct acpi_processor_performance *performance, unsigned int cpu) { struct acpi_processor *pr; ACPI_FUNCTION_TRACE("acpi_processor_unregister_performance"); down(&performance_sem); pr = processors[cpu]; if (!pr) { up(&performance_sem); return_VOID; } kfree(pr->performance->states); pr->performance = NULL; acpi_cpufreq_remove_file(pr); up(&performance_sem); return_VOID; } EXPORT_SYMBOL(acpi_processor_unregister_performance);