![Zhao Yakui](/assets/img/avatar_default.png)
When a T-state limit change notification is received, Linux must evaluate _TPC and change its current T-state immediately to comply with the new limit. Previously, Linux would notice the new limit only upon the next throttling change. Signed-off-by: Zhao Yakui <yakui.zhao@intel.com> Signed-off-by: Li Shaohua <shaohua.li@intel.com> Signed-off-by: Len Brown <len.brown@intel.com>
789 lines
20 KiB
C
789 lines
20 KiB
C
/*
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* processor_throttling.c - Throttling submodule of the ACPI processor driver
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*
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* Copyright (C) 2001, 2002 Andy Grover <andrew.grover@intel.com>
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* Copyright (C) 2001, 2002 Paul Diefenbaugh <paul.s.diefenbaugh@intel.com>
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* Copyright (C) 2004 Dominik Brodowski <linux@brodo.de>
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* Copyright (C) 2004 Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com>
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* - Added processor hotplug support
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*
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* ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
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*
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* This program is free software; you can redistribute it and/or modify
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* it under the terms of the GNU General Public License as published by
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* the Free Software Foundation; either version 2 of the License, or (at
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* your option) any later version.
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*
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* This program is distributed in the hope that it will be useful, but
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* WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
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* General Public License for more details.
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*
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* You should have received a copy of the GNU General Public License along
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* with this program; if not, write to the Free Software Foundation, Inc.,
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* 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
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*
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* ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
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*/
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#include <linux/kernel.h>
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#include <linux/module.h>
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#include <linux/init.h>
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#include <linux/cpufreq.h>
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#include <linux/proc_fs.h>
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#include <linux/seq_file.h>
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#include <asm/io.h>
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#include <asm/uaccess.h>
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#include <acpi/acpi_bus.h>
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#include <acpi/processor.h>
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#define ACPI_PROCESSOR_COMPONENT 0x01000000
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#define ACPI_PROCESSOR_CLASS "processor"
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#define _COMPONENT ACPI_PROCESSOR_COMPONENT
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ACPI_MODULE_NAME("processor_throttling");
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static int acpi_processor_get_throttling(struct acpi_processor *pr);
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int acpi_processor_set_throttling(struct acpi_processor *pr, int state);
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/*
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* _TPC - Throttling Present Capabilities
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*/
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static int acpi_processor_get_platform_limit(struct acpi_processor *pr)
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{
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acpi_status status = 0;
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unsigned long tpc = 0;
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if (!pr)
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return -EINVAL;
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status = acpi_evaluate_integer(pr->handle, "_TPC", NULL, &tpc);
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if (ACPI_FAILURE(status)) {
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if (status != AE_NOT_FOUND) {
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ACPI_EXCEPTION((AE_INFO, status, "Evaluating _TPC"));
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}
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return -ENODEV;
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}
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pr->throttling_platform_limit = (int)tpc;
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return 0;
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}
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int acpi_processor_tstate_has_changed(struct acpi_processor *pr)
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{
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int result = 0;
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int throttling_limit;
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int current_state;
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struct acpi_processor_limit *limit;
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int target_state;
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result = acpi_processor_get_platform_limit(pr);
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if (result) {
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/* Throttling Limit is unsupported */
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return result;
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}
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throttling_limit = pr->throttling_platform_limit;
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if (throttling_limit >= pr->throttling.state_count) {
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/* Uncorrect Throttling Limit */
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return -EINVAL;
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}
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current_state = pr->throttling.state;
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if (current_state > throttling_limit) {
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/*
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* The current state can meet the requirement of
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* _TPC limit. But it is reasonable that OSPM changes
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* t-states from high to low for better performance.
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* Of course the limit condition of thermal
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* and user should be considered.
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*/
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limit = &pr->limit;
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target_state = throttling_limit;
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if (limit->thermal.tx > target_state)
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target_state = limit->thermal.tx;
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if (limit->user.tx > target_state)
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target_state = limit->user.tx;
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} else if (current_state == throttling_limit) {
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/*
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* Unnecessary to change the throttling state
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*/
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return 0;
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} else {
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/*
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* If the current state is lower than the limit of _TPC, it
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* will be forced to switch to the throttling state defined
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* by throttling_platfor_limit.
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* Because the previous state meets with the limit condition
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* of thermal and user, it is unnecessary to check it again.
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*/
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target_state = throttling_limit;
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}
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return acpi_processor_set_throttling(pr, target_state);
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}
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/*
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* _PTC - Processor Throttling Control (and status) register location
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*/
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static int acpi_processor_get_throttling_control(struct acpi_processor *pr)
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{
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int result = 0;
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acpi_status status = 0;
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struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
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union acpi_object *ptc = NULL;
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union acpi_object obj = { 0 };
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status = acpi_evaluate_object(pr->handle, "_PTC", NULL, &buffer);
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if (ACPI_FAILURE(status)) {
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if (status != AE_NOT_FOUND) {
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ACPI_EXCEPTION((AE_INFO, status, "Evaluating _PTC"));
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}
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return -ENODEV;
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}
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ptc = (union acpi_object *)buffer.pointer;
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if (!ptc || (ptc->type != ACPI_TYPE_PACKAGE)
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|| (ptc->package.count != 2)) {
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printk(KERN_ERR PREFIX "Invalid _PTC data\n");
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result = -EFAULT;
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goto end;
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}
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/*
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* control_register
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*/
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obj = ptc->package.elements[0];
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if ((obj.type != ACPI_TYPE_BUFFER)
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|| (obj.buffer.length < sizeof(struct acpi_ptc_register))
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|| (obj.buffer.pointer == NULL)) {
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printk(KERN_ERR PREFIX
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"Invalid _PTC data (control_register)\n");
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result = -EFAULT;
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goto end;
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}
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memcpy(&pr->throttling.control_register, obj.buffer.pointer,
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sizeof(struct acpi_ptc_register));
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/*
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* status_register
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*/
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obj = ptc->package.elements[1];
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if ((obj.type != ACPI_TYPE_BUFFER)
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|| (obj.buffer.length < sizeof(struct acpi_ptc_register))
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|| (obj.buffer.pointer == NULL)) {
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printk(KERN_ERR PREFIX "Invalid _PTC data (status_register)\n");
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result = -EFAULT;
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goto end;
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}
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memcpy(&pr->throttling.status_register, obj.buffer.pointer,
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sizeof(struct acpi_ptc_register));
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end:
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kfree(buffer.pointer);
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return result;
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}
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/*
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* _TSS - Throttling Supported States
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*/
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static int acpi_processor_get_throttling_states(struct acpi_processor *pr)
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{
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int result = 0;
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acpi_status status = AE_OK;
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struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
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struct acpi_buffer format = { sizeof("NNNNN"), "NNNNN" };
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struct acpi_buffer state = { 0, NULL };
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union acpi_object *tss = NULL;
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int i;
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status = acpi_evaluate_object(pr->handle, "_TSS", NULL, &buffer);
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if (ACPI_FAILURE(status)) {
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if (status != AE_NOT_FOUND) {
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ACPI_EXCEPTION((AE_INFO, status, "Evaluating _TSS"));
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}
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return -ENODEV;
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}
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tss = buffer.pointer;
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if (!tss || (tss->type != ACPI_TYPE_PACKAGE)) {
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printk(KERN_ERR PREFIX "Invalid _TSS data\n");
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result = -EFAULT;
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goto end;
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}
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ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found %d throttling states\n",
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tss->package.count));
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pr->throttling.state_count = tss->package.count;
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pr->throttling.states_tss =
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kmalloc(sizeof(struct acpi_processor_tx_tss) * tss->package.count,
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GFP_KERNEL);
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if (!pr->throttling.states_tss) {
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result = -ENOMEM;
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goto end;
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}
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for (i = 0; i < pr->throttling.state_count; i++) {
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struct acpi_processor_tx_tss *tx =
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(struct acpi_processor_tx_tss *)&(pr->throttling.
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states_tss[i]);
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state.length = sizeof(struct acpi_processor_tx_tss);
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state.pointer = tx;
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ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Extracting state %d\n", i));
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status = acpi_extract_package(&(tss->package.elements[i]),
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&format, &state);
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if (ACPI_FAILURE(status)) {
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ACPI_EXCEPTION((AE_INFO, status, "Invalid _TSS data"));
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result = -EFAULT;
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kfree(pr->throttling.states_tss);
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goto end;
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}
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if (!tx->freqpercentage) {
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printk(KERN_ERR PREFIX
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"Invalid _TSS data: freq is zero\n");
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result = -EFAULT;
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kfree(pr->throttling.states_tss);
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goto end;
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}
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}
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end:
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kfree(buffer.pointer);
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return result;
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}
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/*
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* _TSD - T-State Dependencies
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*/
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static int acpi_processor_get_tsd(struct acpi_processor *pr)
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{
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int result = 0;
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acpi_status status = AE_OK;
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struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
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struct acpi_buffer format = { sizeof("NNNNN"), "NNNNN" };
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struct acpi_buffer state = { 0, NULL };
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union acpi_object *tsd = NULL;
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struct acpi_tsd_package *pdomain;
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status = acpi_evaluate_object(pr->handle, "_TSD", NULL, &buffer);
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if (ACPI_FAILURE(status)) {
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if (status != AE_NOT_FOUND) {
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ACPI_EXCEPTION((AE_INFO, status, "Evaluating _TSD"));
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}
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return -ENODEV;
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}
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tsd = buffer.pointer;
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if (!tsd || (tsd->type != ACPI_TYPE_PACKAGE)) {
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ACPI_DEBUG_PRINT((ACPI_DB_ERROR, "Invalid _TSD data\n"));
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result = -EFAULT;
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goto end;
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}
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if (tsd->package.count != 1) {
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ACPI_DEBUG_PRINT((ACPI_DB_ERROR, "Invalid _TSD data\n"));
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result = -EFAULT;
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goto end;
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}
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pdomain = &(pr->throttling.domain_info);
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state.length = sizeof(struct acpi_tsd_package);
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state.pointer = pdomain;
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status = acpi_extract_package(&(tsd->package.elements[0]),
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&format, &state);
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if (ACPI_FAILURE(status)) {
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ACPI_DEBUG_PRINT((ACPI_DB_ERROR, "Invalid _TSD data\n"));
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result = -EFAULT;
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goto end;
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}
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if (pdomain->num_entries != ACPI_TSD_REV0_ENTRIES) {
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ACPI_DEBUG_PRINT((ACPI_DB_ERROR, "Unknown _TSD:num_entries\n"));
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result = -EFAULT;
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goto end;
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}
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if (pdomain->revision != ACPI_TSD_REV0_REVISION) {
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ACPI_DEBUG_PRINT((ACPI_DB_ERROR, "Unknown _TSD:revision\n"));
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result = -EFAULT;
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goto end;
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}
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end:
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kfree(buffer.pointer);
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return result;
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}
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/* --------------------------------------------------------------------------
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Throttling Control
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-------------------------------------------------------------------------- */
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static int acpi_processor_get_throttling_fadt(struct acpi_processor *pr)
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{
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int state = 0;
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u32 value = 0;
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u32 duty_mask = 0;
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u32 duty_value = 0;
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if (!pr)
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return -EINVAL;
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if (!pr->flags.throttling)
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return -ENODEV;
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pr->throttling.state = 0;
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duty_mask = pr->throttling.state_count - 1;
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duty_mask <<= pr->throttling.duty_offset;
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local_irq_disable();
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value = inl(pr->throttling.address);
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/*
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* Compute the current throttling state when throttling is enabled
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* (bit 4 is on).
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*/
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if (value & 0x10) {
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duty_value = value & duty_mask;
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duty_value >>= pr->throttling.duty_offset;
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if (duty_value)
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state = pr->throttling.state_count - duty_value;
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}
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pr->throttling.state = state;
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local_irq_enable();
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ACPI_DEBUG_PRINT((ACPI_DB_INFO,
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"Throttling state is T%d (%d%% throttling applied)\n",
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state, pr->throttling.states[state].performance));
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return 0;
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}
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static int acpi_read_throttling_status(struct acpi_processor_throttling
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*throttling)
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{
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int value = -1;
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switch (throttling->status_register.space_id) {
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case ACPI_ADR_SPACE_SYSTEM_IO:
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acpi_os_read_port((acpi_io_address) throttling->status_register.
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address, &value,
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(u32) throttling->status_register.bit_width *
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8);
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break;
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case ACPI_ADR_SPACE_FIXED_HARDWARE:
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printk(KERN_ERR PREFIX
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"HARDWARE addr space,NOT supported yet\n");
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break;
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default:
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printk(KERN_ERR PREFIX "Unknown addr space %d\n",
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(u32) (throttling->status_register.space_id));
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}
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return value;
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}
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static int acpi_write_throttling_state(struct acpi_processor_throttling
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*throttling, int value)
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{
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int ret = -1;
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switch (throttling->control_register.space_id) {
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case ACPI_ADR_SPACE_SYSTEM_IO:
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acpi_os_write_port((acpi_io_address) throttling->
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control_register.address, value,
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(u32) throttling->control_register.
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bit_width * 8);
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ret = 0;
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break;
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case ACPI_ADR_SPACE_FIXED_HARDWARE:
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printk(KERN_ERR PREFIX
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"HARDWARE addr space,NOT supported yet\n");
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break;
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default:
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printk(KERN_ERR PREFIX "Unknown addr space %d\n",
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(u32) (throttling->control_register.space_id));
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}
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return ret;
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}
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static int acpi_get_throttling_state(struct acpi_processor *pr, int value)
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{
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int i;
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for (i = 0; i < pr->throttling.state_count; i++) {
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struct acpi_processor_tx_tss *tx =
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(struct acpi_processor_tx_tss *)&(pr->throttling.
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states_tss[i]);
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if (tx->control == value)
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break;
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}
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if (i > pr->throttling.state_count)
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i = -1;
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return i;
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}
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static int acpi_get_throttling_value(struct acpi_processor *pr, int state)
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{
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int value = -1;
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if (state >= 0 && state <= pr->throttling.state_count) {
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struct acpi_processor_tx_tss *tx =
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(struct acpi_processor_tx_tss *)&(pr->throttling.
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states_tss[state]);
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value = tx->control;
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}
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return value;
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}
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static int acpi_processor_get_throttling_ptc(struct acpi_processor *pr)
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{
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int state = 0;
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u32 value = 0;
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if (!pr)
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return -EINVAL;
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if (!pr->flags.throttling)
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return -ENODEV;
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pr->throttling.state = 0;
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local_irq_disable();
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value = acpi_read_throttling_status(&pr->throttling);
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if (value >= 0) {
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state = acpi_get_throttling_state(pr, value);
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pr->throttling.state = state;
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}
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local_irq_enable();
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return 0;
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}
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static int acpi_processor_get_throttling(struct acpi_processor *pr)
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{
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return pr->throttling.acpi_processor_get_throttling(pr);
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}
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|
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static int acpi_processor_set_throttling_fadt(struct acpi_processor *pr,
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int state)
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{
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u32 value = 0;
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u32 duty_mask = 0;
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u32 duty_value = 0;
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if (!pr)
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return -EINVAL;
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if ((state < 0) || (state > (pr->throttling.state_count - 1)))
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return -EINVAL;
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if (!pr->flags.throttling)
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return -ENODEV;
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|
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if (state == pr->throttling.state)
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return 0;
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if (state < pr->throttling_platform_limit)
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return -EPERM;
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/*
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* Calculate the duty_value and duty_mask.
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*/
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if (state) {
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duty_value = pr->throttling.state_count - state;
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|
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duty_value <<= pr->throttling.duty_offset;
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/* Used to clear all duty_value bits */
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duty_mask = pr->throttling.state_count - 1;
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|
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duty_mask <<= acpi_gbl_FADT.duty_offset;
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duty_mask = ~duty_mask;
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}
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local_irq_disable();
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|
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/*
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* Disable throttling by writing a 0 to bit 4. Note that we must
|
|
* turn it off before you can change the duty_value.
|
|
*/
|
|
value = inl(pr->throttling.address);
|
|
if (value & 0x10) {
|
|
value &= 0xFFFFFFEF;
|
|
outl(value, pr->throttling.address);
|
|
}
|
|
|
|
/*
|
|
* Write the new duty_value and then enable throttling. Note
|
|
* that a state value of 0 leaves throttling disabled.
|
|
*/
|
|
if (state) {
|
|
value &= duty_mask;
|
|
value |= duty_value;
|
|
outl(value, pr->throttling.address);
|
|
|
|
value |= 0x00000010;
|
|
outl(value, pr->throttling.address);
|
|
}
|
|
|
|
pr->throttling.state = state;
|
|
|
|
local_irq_enable();
|
|
|
|
ACPI_DEBUG_PRINT((ACPI_DB_INFO,
|
|
"Throttling state set to T%d (%d%%)\n", state,
|
|
(pr->throttling.states[state].performance ? pr->
|
|
throttling.states[state].performance / 10 : 0)));
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int acpi_processor_set_throttling_ptc(struct acpi_processor *pr,
|
|
int state)
|
|
{
|
|
u32 value = 0;
|
|
|
|
if (!pr)
|
|
return -EINVAL;
|
|
|
|
if ((state < 0) || (state > (pr->throttling.state_count - 1)))
|
|
return -EINVAL;
|
|
|
|
if (!pr->flags.throttling)
|
|
return -ENODEV;
|
|
|
|
if (state == pr->throttling.state)
|
|
return 0;
|
|
|
|
if (state < pr->throttling_platform_limit)
|
|
return -EPERM;
|
|
|
|
local_irq_disable();
|
|
|
|
value = acpi_get_throttling_value(pr, state);
|
|
if (value >= 0) {
|
|
acpi_write_throttling_state(&pr->throttling, value);
|
|
pr->throttling.state = state;
|
|
}
|
|
local_irq_enable();
|
|
|
|
return 0;
|
|
}
|
|
|
|
int acpi_processor_set_throttling(struct acpi_processor *pr, int state)
|
|
{
|
|
return pr->throttling.acpi_processor_set_throttling(pr, state);
|
|
}
|
|
|
|
int acpi_processor_get_throttling_info(struct acpi_processor *pr)
|
|
{
|
|
int result = 0;
|
|
int step = 0;
|
|
int i = 0;
|
|
|
|
ACPI_DEBUG_PRINT((ACPI_DB_INFO,
|
|
"pblk_address[0x%08x] duty_offset[%d] duty_width[%d]\n",
|
|
pr->throttling.address,
|
|
pr->throttling.duty_offset,
|
|
pr->throttling.duty_width));
|
|
|
|
if (!pr)
|
|
return -EINVAL;
|
|
|
|
/*
|
|
* Evaluate _PTC, _TSS and _TPC
|
|
* They must all be present or none of them can be used.
|
|
*/
|
|
if (acpi_processor_get_throttling_control(pr) ||
|
|
acpi_processor_get_throttling_states(pr) ||
|
|
acpi_processor_get_platform_limit(pr))
|
|
{
|
|
pr->throttling.acpi_processor_get_throttling =
|
|
&acpi_processor_get_throttling_fadt;
|
|
pr->throttling.acpi_processor_set_throttling =
|
|
&acpi_processor_set_throttling_fadt;
|
|
} else {
|
|
pr->throttling.acpi_processor_get_throttling =
|
|
&acpi_processor_get_throttling_ptc;
|
|
pr->throttling.acpi_processor_set_throttling =
|
|
&acpi_processor_set_throttling_ptc;
|
|
}
|
|
|
|
acpi_processor_get_tsd(pr);
|
|
|
|
if (!pr->throttling.address) {
|
|
ACPI_DEBUG_PRINT((ACPI_DB_INFO, "No throttling register\n"));
|
|
return 0;
|
|
} else if (!pr->throttling.duty_width) {
|
|
ACPI_DEBUG_PRINT((ACPI_DB_INFO, "No throttling states\n"));
|
|
return 0;
|
|
}
|
|
/* TBD: Support duty_cycle values that span bit 4. */
|
|
else if ((pr->throttling.duty_offset + pr->throttling.duty_width) > 4) {
|
|
printk(KERN_WARNING PREFIX "duty_cycle spans bit 4\n");
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* PIIX4 Errata: We don't support throttling on the original PIIX4.
|
|
* This shouldn't be an issue as few (if any) mobile systems ever
|
|
* used this part.
|
|
*/
|
|
if (errata.piix4.throttle) {
|
|
ACPI_DEBUG_PRINT((ACPI_DB_INFO,
|
|
"Throttling not supported on PIIX4 A- or B-step\n"));
|
|
return 0;
|
|
}
|
|
|
|
pr->throttling.state_count = 1 << acpi_gbl_FADT.duty_width;
|
|
|
|
/*
|
|
* Compute state values. Note that throttling displays a linear power/
|
|
* performance relationship (at 50% performance the CPU will consume
|
|
* 50% power). Values are in 1/10th of a percent to preserve accuracy.
|
|
*/
|
|
|
|
step = (1000 / pr->throttling.state_count);
|
|
|
|
for (i = 0; i < pr->throttling.state_count; i++) {
|
|
pr->throttling.states[i].performance = step * i;
|
|
pr->throttling.states[i].power = step * i;
|
|
}
|
|
|
|
ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found %d throttling states\n",
|
|
pr->throttling.state_count));
|
|
|
|
pr->flags.throttling = 1;
|
|
|
|
/*
|
|
* Disable throttling (if enabled). We'll let subsequent policy (e.g.
|
|
* thermal) decide to lower performance if it so chooses, but for now
|
|
* we'll crank up the speed.
|
|
*/
|
|
|
|
result = acpi_processor_get_throttling(pr);
|
|
if (result)
|
|
goto end;
|
|
|
|
if (pr->throttling.state) {
|
|
ACPI_DEBUG_PRINT((ACPI_DB_INFO,
|
|
"Disabling throttling (was T%d)\n",
|
|
pr->throttling.state));
|
|
result = acpi_processor_set_throttling(pr, 0);
|
|
if (result)
|
|
goto end;
|
|
}
|
|
|
|
end:
|
|
if (result)
|
|
pr->flags.throttling = 0;
|
|
|
|
return result;
|
|
}
|
|
|
|
/* proc interface */
|
|
|
|
static int acpi_processor_throttling_seq_show(struct seq_file *seq,
|
|
void *offset)
|
|
{
|
|
struct acpi_processor *pr = seq->private;
|
|
int i = 0;
|
|
int result = 0;
|
|
|
|
if (!pr)
|
|
goto end;
|
|
|
|
if (!(pr->throttling.state_count > 0)) {
|
|
seq_puts(seq, "<not supported>\n");
|
|
goto end;
|
|
}
|
|
|
|
result = acpi_processor_get_throttling(pr);
|
|
|
|
if (result) {
|
|
seq_puts(seq,
|
|
"Could not determine current throttling state.\n");
|
|
goto end;
|
|
}
|
|
|
|
seq_printf(seq, "state count: %d\n"
|
|
"active state: T%d\n"
|
|
"state available: T%d to T%d\n",
|
|
pr->throttling.state_count, pr->throttling.state,
|
|
pr->throttling_platform_limit,
|
|
pr->throttling.state_count - 1);
|
|
|
|
seq_puts(seq, "states:\n");
|
|
if (pr->throttling.acpi_processor_get_throttling ==
|
|
acpi_processor_get_throttling_fadt) {
|
|
for (i = 0; i < pr->throttling.state_count; i++)
|
|
seq_printf(seq, " %cT%d: %02d%%\n",
|
|
(i == pr->throttling.state ? '*' : ' '), i,
|
|
(pr->throttling.states[i].performance ? pr->
|
|
throttling.states[i].performance / 10 : 0));
|
|
} else {
|
|
for (i = 0; i < pr->throttling.state_count; i++)
|
|
seq_printf(seq, " %cT%d: %02d%%\n",
|
|
(i == pr->throttling.state ? '*' : ' '), i,
|
|
(int)pr->throttling.states_tss[i].
|
|
freqpercentage);
|
|
}
|
|
|
|
end:
|
|
return 0;
|
|
}
|
|
|
|
static int acpi_processor_throttling_open_fs(struct inode *inode,
|
|
struct file *file)
|
|
{
|
|
return single_open(file, acpi_processor_throttling_seq_show,
|
|
PDE(inode)->data);
|
|
}
|
|
|
|
static ssize_t acpi_processor_write_throttling(struct file *file,
|
|
const char __user * buffer,
|
|
size_t count, loff_t * data)
|
|
{
|
|
int result = 0;
|
|
struct seq_file *m = file->private_data;
|
|
struct acpi_processor *pr = m->private;
|
|
char state_string[12] = { '\0' };
|
|
|
|
if (!pr || (count > sizeof(state_string) - 1))
|
|
return -EINVAL;
|
|
|
|
if (copy_from_user(state_string, buffer, count))
|
|
return -EFAULT;
|
|
|
|
state_string[count] = '\0';
|
|
|
|
result = acpi_processor_set_throttling(pr,
|
|
simple_strtoul(state_string,
|
|
NULL, 0));
|
|
if (result)
|
|
return result;
|
|
|
|
return count;
|
|
}
|
|
|
|
struct file_operations acpi_processor_throttling_fops = {
|
|
.open = acpi_processor_throttling_open_fs,
|
|
.read = seq_read,
|
|
.write = acpi_processor_write_throttling,
|
|
.llseek = seq_lseek,
|
|
.release = single_release,
|
|
};
|