/* * processor_throttling.c - Throttling submodule of the ACPI processor driver * * 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/slab.h> #include <linux/init.h> #include <linux/sched.h> #include <linux/cpufreq.h> #include <asm/io.h> #include <asm/uaccess.h> #include <acpi/acpi_bus.h> #include <acpi/acpi_drivers.h> #include <acpi/processor.h> #define PREFIX "ACPI: " #define ACPI_PROCESSOR_CLASS "processor" #define _COMPONENT ACPI_PROCESSOR_COMPONENT ACPI_MODULE_NAME("processor_throttling"); /* ignore_tpc: * 0 -> acpi processor driver doesn't ignore _TPC values * 1 -> acpi processor driver ignores _TPC values */ static int ignore_tpc; module_param(ignore_tpc, int, 0644); MODULE_PARM_DESC(ignore_tpc, "Disable broken BIOS _TPC throttling support"); struct throttling_tstate { unsigned int cpu; /* cpu nr */ int target_state; /* target T-state */ }; #define THROTTLING_PRECHANGE (1) #define THROTTLING_POSTCHANGE (2) static int acpi_processor_get_throttling(struct acpi_processor *pr); int acpi_processor_set_throttling(struct acpi_processor *pr, int state, bool force); static int acpi_processor_update_tsd_coord(void) { int count, count_target; int retval = 0; unsigned int i, j; cpumask_var_t covered_cpus; struct acpi_processor *pr, *match_pr; struct acpi_tsd_package *pdomain, *match_pdomain; struct acpi_processor_throttling *pthrottling, *match_pthrottling; if (!zalloc_cpumask_var(&covered_cpus, GFP_KERNEL)) return -ENOMEM; /* * Now that we have _TSD data from all CPUs, lets setup T-state * coordination between all CPUs. */ for_each_possible_cpu(i) { pr = per_cpu(processors, i); if (!pr) continue; /* Basic validity check for domain info */ pthrottling = &(pr->throttling); /* * If tsd package for one cpu is invalid, the coordination * among all CPUs is thought as invalid. * Maybe it is ugly. */ if (!pthrottling->tsd_valid_flag) { retval = -EINVAL; break; } } if (retval) goto err_ret; for_each_possible_cpu(i) { pr = per_cpu(processors, i); if (!pr) continue; if (cpumask_test_cpu(i, covered_cpus)) continue; pthrottling = &pr->throttling; pdomain = &(pthrottling->domain_info); cpumask_set_cpu(i, pthrottling->shared_cpu_map); cpumask_set_cpu(i, covered_cpus); /* * If the number of processor in the TSD domain is 1, it is * unnecessary to parse the coordination for this CPU. */ if (pdomain->num_processors <= 1) continue; /* Validate the Domain info */ count_target = pdomain->num_processors; count = 1; for_each_possible_cpu(j) { if (i == j) continue; match_pr = per_cpu(processors, j); if (!match_pr) continue; match_pthrottling = &(match_pr->throttling); match_pdomain = &(match_pthrottling->domain_info); if (match_pdomain->domain != pdomain->domain) continue; /* Here i and j are in the same domain. * If two TSD packages have the same domain, they * should have the same num_porcessors and * coordination type. Otherwise it will be regarded * as illegal. */ if (match_pdomain->num_processors != count_target) { retval = -EINVAL; goto err_ret; } if (pdomain->coord_type != match_pdomain->coord_type) { retval = -EINVAL; goto err_ret; } cpumask_set_cpu(j, covered_cpus); cpumask_set_cpu(j, pthrottling->shared_cpu_map); count++; } for_each_possible_cpu(j) { if (i == j) continue; match_pr = per_cpu(processors, j); if (!match_pr) continue; match_pthrottling = &(match_pr->throttling); match_pdomain = &(match_pthrottling->domain_info); if (match_pdomain->domain != pdomain->domain) continue; /* * If some CPUS have the same domain, they * will have the same shared_cpu_map. */ cpumask_copy(match_pthrottling->shared_cpu_map, pthrottling->shared_cpu_map); } } err_ret: free_cpumask_var(covered_cpus); for_each_possible_cpu(i) { pr = per_cpu(processors, i); if (!pr) continue; /* * Assume no coordination on any error parsing domain info. * The coordination type will be forced as SW_ALL. */ if (retval) { pthrottling = &(pr->throttling); cpumask_clear(pthrottling->shared_cpu_map); cpumask_set_cpu(i, pthrottling->shared_cpu_map); pthrottling->shared_type = DOMAIN_COORD_TYPE_SW_ALL; } } return retval; } /* * Update the T-state coordination after the _TSD * data for all cpus is obtained. */ void acpi_processor_throttling_init(void) { if (acpi_processor_update_tsd_coord()) ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Assume no T-state coordination\n")); return; } static int acpi_processor_throttling_notifier(unsigned long event, void *data) { struct throttling_tstate *p_tstate = data; struct acpi_processor *pr; unsigned int cpu ; int target_state; struct acpi_processor_limit *p_limit; struct acpi_processor_throttling *p_throttling; cpu = p_tstate->cpu; pr = per_cpu(processors, cpu); if (!pr) { ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Invalid pr pointer\n")); return 0; } if (!pr->flags.throttling) { ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Throttling control is " "unsupported on CPU %d\n", cpu)); return 0; } target_state = p_tstate->target_state; p_throttling = &(pr->throttling); switch (event) { case THROTTLING_PRECHANGE: /* * Prechange event is used to choose one proper t-state, * which meets the limits of thermal, user and _TPC. */ p_limit = &pr->limit; if (p_limit->thermal.tx > target_state) target_state = p_limit->thermal.tx; if (p_limit->user.tx > target_state) target_state = p_limit->user.tx; if (pr->throttling_platform_limit > target_state) target_state = pr->throttling_platform_limit; if (target_state >= p_throttling->state_count) { printk(KERN_WARNING "Exceed the limit of T-state \n"); target_state = p_throttling->state_count - 1; } p_tstate->target_state = target_state; ACPI_DEBUG_PRINT((ACPI_DB_INFO, "PreChange Event:" "target T-state of CPU %d is T%d\n", cpu, target_state)); break; case THROTTLING_POSTCHANGE: /* * Postchange event is only used to update the * T-state flag of acpi_processor_throttling. */ p_throttling->state = target_state; ACPI_DEBUG_PRINT((ACPI_DB_INFO, "PostChange Event:" "CPU %d is switched to T%d\n", cpu, target_state)); break; default: printk(KERN_WARNING "Unsupported Throttling notifier event\n"); break; } return 0; } /* * _TPC - Throttling Present Capabilities */ static int acpi_processor_get_platform_limit(struct acpi_processor *pr) { acpi_status status = 0; unsigned long long tpc = 0; if (!pr) return -EINVAL; if (ignore_tpc) goto end; status = acpi_evaluate_integer(pr->handle, "_TPC", NULL, &tpc); if (ACPI_FAILURE(status)) { if (status != AE_NOT_FOUND) { ACPI_EXCEPTION((AE_INFO, status, "Evaluating _TPC")); } return -ENODEV; } end: pr->throttling_platform_limit = (int)tpc; return 0; } int acpi_processor_tstate_has_changed(struct acpi_processor *pr) { int result = 0; int throttling_limit; int current_state; struct acpi_processor_limit *limit; int target_state; if (ignore_tpc) return 0; result = acpi_processor_get_platform_limit(pr); if (result) { /* Throttling Limit is unsupported */ return result; } throttling_limit = pr->throttling_platform_limit; if (throttling_limit >= pr->throttling.state_count) { /* Uncorrect Throttling Limit */ return -EINVAL; } current_state = pr->throttling.state; if (current_state > throttling_limit) { /* * The current state can meet the requirement of * _TPC limit. But it is reasonable that OSPM changes * t-states from high to low for better performance. * Of course the limit condition of thermal * and user should be considered. */ limit = &pr->limit; target_state = throttling_limit; if (limit->thermal.tx > target_state) target_state = limit->thermal.tx; if (limit->user.tx > target_state) target_state = limit->user.tx; } else if (current_state == throttling_limit) { /* * Unnecessary to change the throttling state */ return 0; } else { /* * If the current state is lower than the limit of _TPC, it * will be forced to switch to the throttling state defined * by throttling_platfor_limit. * Because the previous state meets with the limit condition * of thermal and user, it is unnecessary to check it again. */ target_state = throttling_limit; } return acpi_processor_set_throttling(pr, target_state, false); } /* * This function is used to reevaluate whether the T-state is valid * after one CPU is onlined/offlined. * It is noted that it won't reevaluate the following properties for * the T-state. * 1. Control method. * 2. the number of supported T-state * 3. TSD domain */ void acpi_processor_reevaluate_tstate(struct acpi_processor *pr, unsigned long action) { int result = 0; if (action == CPU_DEAD) { /* When one CPU is offline, the T-state throttling * will be invalidated. */ pr->flags.throttling = 0; return; } /* the following is to recheck whether the T-state is valid for * the online CPU */ if (!pr->throttling.state_count) { /* If the number of T-state is invalid, it is * invalidated. */ pr->flags.throttling = 0; return; } 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) { result = acpi_processor_set_throttling(pr, 0, false); if (result) goto end; } end: if (result) pr->flags.throttling = 0; } /* * _PTC - Processor Throttling Control (and status) register location */ static int acpi_processor_get_throttling_control(struct acpi_processor *pr) { int result = 0; acpi_status status = 0; struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL }; union acpi_object *ptc = NULL; union acpi_object obj = { 0 }; struct acpi_processor_throttling *throttling; status = acpi_evaluate_object(pr->handle, "_PTC", NULL, &buffer); if (ACPI_FAILURE(status)) { if (status != AE_NOT_FOUND) { ACPI_EXCEPTION((AE_INFO, status, "Evaluating _PTC")); } return -ENODEV; } ptc = (union acpi_object *)buffer.pointer; if (!ptc || (ptc->type != ACPI_TYPE_PACKAGE) || (ptc->package.count != 2)) { printk(KERN_ERR PREFIX "Invalid _PTC data\n"); result = -EFAULT; goto end; } /* * control_register */ obj = ptc->package.elements[0]; if ((obj.type != ACPI_TYPE_BUFFER) || (obj.buffer.length < sizeof(struct acpi_ptc_register)) || (obj.buffer.pointer == NULL)) { printk(KERN_ERR PREFIX "Invalid _PTC data (control_register)\n"); result = -EFAULT; goto end; } memcpy(&pr->throttling.control_register, obj.buffer.pointer, sizeof(struct acpi_ptc_register)); /* * status_register */ obj = ptc->package.elements[1]; if ((obj.type != ACPI_TYPE_BUFFER) || (obj.buffer.length < sizeof(struct acpi_ptc_register)) || (obj.buffer.pointer == NULL)) { printk(KERN_ERR PREFIX "Invalid _PTC data (status_register)\n"); result = -EFAULT; goto end; } memcpy(&pr->throttling.status_register, obj.buffer.pointer, sizeof(struct acpi_ptc_register)); throttling = &pr->throttling; if ((throttling->control_register.bit_width + throttling->control_register.bit_offset) > 32) { printk(KERN_ERR PREFIX "Invalid _PTC control register\n"); result = -EFAULT; goto end; } if ((throttling->status_register.bit_width + throttling->status_register.bit_offset) > 32) { printk(KERN_ERR PREFIX "Invalid _PTC status register\n"); result = -EFAULT; goto end; } end: kfree(buffer.pointer); return result; } /* * _TSS - Throttling Supported States */ static int acpi_processor_get_throttling_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("NNNNN"), "NNNNN" }; struct acpi_buffer state = { 0, NULL }; union acpi_object *tss = NULL; int i; status = acpi_evaluate_object(pr->handle, "_TSS", NULL, &buffer); if (ACPI_FAILURE(status)) { if (status != AE_NOT_FOUND) { ACPI_EXCEPTION((AE_INFO, status, "Evaluating _TSS")); } return -ENODEV; } tss = buffer.pointer; if (!tss || (tss->type != ACPI_TYPE_PACKAGE)) { printk(KERN_ERR PREFIX "Invalid _TSS data\n"); result = -EFAULT; goto end; } ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found %d throttling states\n", tss->package.count)); pr->throttling.state_count = tss->package.count; pr->throttling.states_tss = kmalloc(sizeof(struct acpi_processor_tx_tss) * tss->package.count, GFP_KERNEL); if (!pr->throttling.states_tss) { result = -ENOMEM; goto end; } for (i = 0; i < pr->throttling.state_count; i++) { struct acpi_processor_tx_tss *tx = (struct acpi_processor_tx_tss *)&(pr->throttling. states_tss[i]); state.length = sizeof(struct acpi_processor_tx_tss); state.pointer = tx; ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Extracting state %d\n", i)); status = acpi_extract_package(&(tss->package.elements[i]), &format, &state); if (ACPI_FAILURE(status)) { ACPI_EXCEPTION((AE_INFO, status, "Invalid _TSS data")); result = -EFAULT; kfree(pr->throttling.states_tss); goto end; } if (!tx->freqpercentage) { printk(KERN_ERR PREFIX "Invalid _TSS data: freq is zero\n"); result = -EFAULT; kfree(pr->throttling.states_tss); goto end; } } end: kfree(buffer.pointer); return result; } /* * _TSD - T-State Dependencies */ static int acpi_processor_get_tsd(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("NNNNN"), "NNNNN" }; struct acpi_buffer state = { 0, NULL }; union acpi_object *tsd = NULL; struct acpi_tsd_package *pdomain; struct acpi_processor_throttling *pthrottling; pthrottling = &pr->throttling; pthrottling->tsd_valid_flag = 0; status = acpi_evaluate_object(pr->handle, "_TSD", NULL, &buffer); if (ACPI_FAILURE(status)) { if (status != AE_NOT_FOUND) { ACPI_EXCEPTION((AE_INFO, status, "Evaluating _TSD")); } return -ENODEV; } tsd = buffer.pointer; if (!tsd || (tsd->type != ACPI_TYPE_PACKAGE)) { printk(KERN_ERR PREFIX "Invalid _TSD data\n"); result = -EFAULT; goto end; } if (tsd->package.count != 1) { printk(KERN_ERR PREFIX "Invalid _TSD data\n"); result = -EFAULT; goto end; } pdomain = &(pr->throttling.domain_info); state.length = sizeof(struct acpi_tsd_package); state.pointer = pdomain; status = acpi_extract_package(&(tsd->package.elements[0]), &format, &state); if (ACPI_FAILURE(status)) { printk(KERN_ERR PREFIX "Invalid _TSD data\n"); result = -EFAULT; goto end; } if (pdomain->num_entries != ACPI_TSD_REV0_ENTRIES) { printk(KERN_ERR PREFIX "Unknown _TSD:num_entries\n"); result = -EFAULT; goto end; } if (pdomain->revision != ACPI_TSD_REV0_REVISION) { printk(KERN_ERR PREFIX "Unknown _TSD:revision\n"); result = -EFAULT; goto end; } pthrottling = &pr->throttling; pthrottling->tsd_valid_flag = 1; pthrottling->shared_type = pdomain->coord_type; cpumask_set_cpu(pr->id, pthrottling->shared_cpu_map); /* * If the coordination type is not defined in ACPI spec, * the tsd_valid_flag will be clear and coordination type * will be forecd as DOMAIN_COORD_TYPE_SW_ALL. */ if (pdomain->coord_type != DOMAIN_COORD_TYPE_SW_ALL && pdomain->coord_type != DOMAIN_COORD_TYPE_SW_ANY && pdomain->coord_type != DOMAIN_COORD_TYPE_HW_ALL) { pthrottling->tsd_valid_flag = 0; pthrottling->shared_type = DOMAIN_COORD_TYPE_SW_ALL; } end: kfree(buffer.pointer); return result; } /* -------------------------------------------------------------------------- Throttling Control -------------------------------------------------------------------------- */ static int acpi_processor_get_throttling_fadt(struct acpi_processor *pr) { int state = 0; u32 value = 0; u32 duty_mask = 0; u32 duty_value = 0; if (!pr) return -EINVAL; if (!pr->flags.throttling) return -ENODEV; pr->throttling.state = 0; duty_mask = pr->throttling.state_count - 1; duty_mask <<= pr->throttling.duty_offset; local_irq_disable(); value = inl(pr->throttling.address); /* * Compute the current throttling state when throttling is enabled * (bit 4 is on). */ if (value & 0x10) { duty_value = value & duty_mask; duty_value >>= pr->throttling.duty_offset; if (duty_value) state = pr->throttling.state_count - duty_value; } pr->throttling.state = state; local_irq_enable(); ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Throttling state is T%d (%d%% throttling applied)\n", state, pr->throttling.states[state].performance)); return 0; } #ifdef CONFIG_X86 static int acpi_throttling_rdmsr(u64 *value) { u64 msr_high, msr_low; u64 msr = 0; int ret = -1; if ((this_cpu_read(cpu_info.x86_vendor) != X86_VENDOR_INTEL) || !this_cpu_has(X86_FEATURE_ACPI)) { printk(KERN_ERR PREFIX "HARDWARE addr space,NOT supported yet\n"); } else { msr_low = 0; msr_high = 0; rdmsr_safe(MSR_IA32_THERM_CONTROL, (u32 *)&msr_low , (u32 *) &msr_high); msr = (msr_high << 32) | msr_low; *value = (u64) msr; ret = 0; } return ret; } static int acpi_throttling_wrmsr(u64 value) { int ret = -1; u64 msr; if ((this_cpu_read(cpu_info.x86_vendor) != X86_VENDOR_INTEL) || !this_cpu_has(X86_FEATURE_ACPI)) { printk(KERN_ERR PREFIX "HARDWARE addr space,NOT supported yet\n"); } else { msr = value; wrmsr_safe(MSR_IA32_THERM_CONTROL, msr & 0xffffffff, msr >> 32); ret = 0; } return ret; } #else static int acpi_throttling_rdmsr(u64 *value) { printk(KERN_ERR PREFIX "HARDWARE addr space,NOT supported yet\n"); return -1; } static int acpi_throttling_wrmsr(u64 value) { printk(KERN_ERR PREFIX "HARDWARE addr space,NOT supported yet\n"); return -1; } #endif static int acpi_read_throttling_status(struct acpi_processor *pr, u64 *value) { u32 bit_width, bit_offset; u32 ptc_value; u64 ptc_mask; struct acpi_processor_throttling *throttling; int ret = -1; throttling = &pr->throttling; switch (throttling->status_register.space_id) { case ACPI_ADR_SPACE_SYSTEM_IO: bit_width = throttling->status_register.bit_width; bit_offset = throttling->status_register.bit_offset; acpi_os_read_port((acpi_io_address) throttling->status_register. address, &ptc_value, (u32) (bit_width + bit_offset)); ptc_mask = (1 << bit_width) - 1; *value = (u64) ((ptc_value >> bit_offset) & ptc_mask); ret = 0; break; case ACPI_ADR_SPACE_FIXED_HARDWARE: ret = acpi_throttling_rdmsr(value); break; default: printk(KERN_ERR PREFIX "Unknown addr space %d\n", (u32) (throttling->status_register.space_id)); } return ret; } static int acpi_write_throttling_state(struct acpi_processor *pr, u64 value) { u32 bit_width, bit_offset; u64 ptc_value; u64 ptc_mask; struct acpi_processor_throttling *throttling; int ret = -1; throttling = &pr->throttling; switch (throttling->control_register.space_id) { case ACPI_ADR_SPACE_SYSTEM_IO: bit_width = throttling->control_register.bit_width; bit_offset = throttling->control_register.bit_offset; ptc_mask = (1 << bit_width) - 1; ptc_value = value & ptc_mask; acpi_os_write_port((acpi_io_address) throttling-> control_register.address, (u32) (ptc_value << bit_offset), (u32) (bit_width + bit_offset)); ret = 0; break; case ACPI_ADR_SPACE_FIXED_HARDWARE: ret = acpi_throttling_wrmsr(value); break; default: printk(KERN_ERR PREFIX "Unknown addr space %d\n", (u32) (throttling->control_register.space_id)); } return ret; } static int acpi_get_throttling_state(struct acpi_processor *pr, u64 value) { int i; for (i = 0; i < pr->throttling.state_count; i++) { struct acpi_processor_tx_tss *tx = (struct acpi_processor_tx_tss *)&(pr->throttling. states_tss[i]); if (tx->control == value) return i; } return -1; } static int acpi_get_throttling_value(struct acpi_processor *pr, int state, u64 *value) { int ret = -1; if (state >= 0 && state <= pr->throttling.state_count) { struct acpi_processor_tx_tss *tx = (struct acpi_processor_tx_tss *)&(pr->throttling. states_tss[state]); *value = tx->control; ret = 0; } return ret; } static int acpi_processor_get_throttling_ptc(struct acpi_processor *pr) { int state = 0; int ret; u64 value; if (!pr) return -EINVAL; if (!pr->flags.throttling) return -ENODEV; pr->throttling.state = 0; value = 0; ret = acpi_read_throttling_status(pr, &value); if (ret >= 0) { state = acpi_get_throttling_state(pr, value); if (state == -1) { ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Invalid throttling state, reset\n")); state = 0; ret = acpi_processor_set_throttling(pr, state, true); if (ret) return ret; } pr->throttling.state = state; } return 0; } static int acpi_processor_get_throttling(struct acpi_processor *pr) { cpumask_var_t saved_mask; int ret; if (!pr) return -EINVAL; if (!pr->flags.throttling) return -ENODEV; if (!alloc_cpumask_var(&saved_mask, GFP_KERNEL)) return -ENOMEM; /* * Migrate task to the cpu pointed by pr. */ cpumask_copy(saved_mask, ¤t->cpus_allowed); /* FIXME: use work_on_cpu() */ if (set_cpus_allowed_ptr(current, cpumask_of(pr->id))) { /* Can't migrate to the target pr->id CPU. Exit */ free_cpumask_var(saved_mask); return -ENODEV; } ret = pr->throttling.acpi_processor_get_throttling(pr); /* restore the previous state */ set_cpus_allowed_ptr(current, saved_mask); free_cpumask_var(saved_mask); return ret; } static int acpi_processor_get_fadt_info(struct acpi_processor *pr) { int i, step; if (!pr->throttling.address) { ACPI_DEBUG_PRINT((ACPI_DB_INFO, "No throttling register\n")); return -EINVAL; } else if (!pr->throttling.duty_width) { ACPI_DEBUG_PRINT((ACPI_DB_INFO, "No throttling states\n")); return -EINVAL; } /* 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 -EINVAL; } 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 = 1000 - step * i; pr->throttling.states[i].power = 1000 - step * i; } return 0; } static int acpi_processor_set_throttling_fadt(struct acpi_processor *pr, int state, bool force) { u32 value = 0; u32 duty_mask = 0; u32 duty_value = 0; if (!pr) return -EINVAL; if ((state < 0) || (state > (pr->throttling.state_count - 1))) return -EINVAL; if (!pr->flags.throttling) return -ENODEV; if (!force && (state == pr->throttling.state)) return 0; if (state < pr->throttling_platform_limit) return -EPERM; /* * Calculate the duty_value and duty_mask. */ if (state) { duty_value = pr->throttling.state_count - state; duty_value <<= pr->throttling.duty_offset; /* Used to clear all duty_value bits */ duty_mask = pr->throttling.state_count - 1; duty_mask <<= acpi_gbl_FADT.duty_offset; duty_mask = ~duty_mask; } local_irq_disable(); /* * 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, bool force) { int ret; u64 value; if (!pr) return -EINVAL; if ((state < 0) || (state > (pr->throttling.state_count - 1))) return -EINVAL; if (!pr->flags.throttling) return -ENODEV; if (!force && (state == pr->throttling.state)) return 0; if (state < pr->throttling_platform_limit) return -EPERM; value = 0; ret = acpi_get_throttling_value(pr, state, &value); if (ret >= 0) { acpi_write_throttling_state(pr, value); pr->throttling.state = state; } return 0; } int acpi_processor_set_throttling(struct acpi_processor *pr, int state, bool force) { cpumask_var_t saved_mask; int ret = 0; unsigned int i; struct acpi_processor *match_pr; struct acpi_processor_throttling *p_throttling; struct throttling_tstate t_state; cpumask_var_t online_throttling_cpus; if (!pr) return -EINVAL; if (!pr->flags.throttling) return -ENODEV; if ((state < 0) || (state > (pr->throttling.state_count - 1))) return -EINVAL; if (!alloc_cpumask_var(&saved_mask, GFP_KERNEL)) return -ENOMEM; if (!alloc_cpumask_var(&online_throttling_cpus, GFP_KERNEL)) { free_cpumask_var(saved_mask); return -ENOMEM; } if (cpu_is_offline(pr->id)) { /* * the cpu pointed by pr->id is offline. Unnecessary to change * the throttling state any more. */ return -ENODEV; } cpumask_copy(saved_mask, ¤t->cpus_allowed); t_state.target_state = state; p_throttling = &(pr->throttling); cpumask_and(online_throttling_cpus, cpu_online_mask, p_throttling->shared_cpu_map); /* * The throttling notifier will be called for every * affected cpu in order to get one proper T-state. * The notifier event is THROTTLING_PRECHANGE. */ for_each_cpu(i, online_throttling_cpus) { t_state.cpu = i; acpi_processor_throttling_notifier(THROTTLING_PRECHANGE, &t_state); } /* * The function of acpi_processor_set_throttling will be called * to switch T-state. If the coordination type is SW_ALL or HW_ALL, * it is necessary to call it for every affected cpu. Otherwise * it can be called only for the cpu pointed by pr. */ if (p_throttling->shared_type == DOMAIN_COORD_TYPE_SW_ANY) { /* FIXME: use work_on_cpu() */ if (set_cpus_allowed_ptr(current, cpumask_of(pr->id))) { /* Can't migrate to the pr->id CPU. Exit */ ret = -ENODEV; goto exit; } ret = p_throttling->acpi_processor_set_throttling(pr, t_state.target_state, force); } else { /* * When the T-state coordination is SW_ALL or HW_ALL, * it is necessary to set T-state for every affected * cpus. */ for_each_cpu(i, online_throttling_cpus) { match_pr = per_cpu(processors, i); /* * If the pointer is invalid, we will report the * error message and continue. */ if (!match_pr) { ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Invalid Pointer for CPU %d\n", i)); continue; } /* * If the throttling control is unsupported on CPU i, * we will report the error message and continue. */ if (!match_pr->flags.throttling) { ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Throttling Control is unsupported " "on CPU %d\n", i)); continue; } t_state.cpu = i; /* FIXME: use work_on_cpu() */ if (set_cpus_allowed_ptr(current, cpumask_of(i))) continue; ret = match_pr->throttling. acpi_processor_set_throttling( match_pr, t_state.target_state, force); } } /* * After the set_throttling is called, the * throttling notifier is called for every * affected cpu to update the T-states. * The notifier event is THROTTLING_POSTCHANGE */ for_each_cpu(i, online_throttling_cpus) { t_state.cpu = i; acpi_processor_throttling_notifier(THROTTLING_POSTCHANGE, &t_state); } /* restore the previous state */ /* FIXME: use work_on_cpu() */ set_cpus_allowed_ptr(current, saved_mask); exit: free_cpumask_var(online_throttling_cpus); free_cpumask_var(saved_mask); return ret; } int acpi_processor_get_throttling_info(struct acpi_processor *pr) { int result = 0; struct acpi_processor_throttling *pthrottling; 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)); /* * 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; if (acpi_processor_get_fadt_info(pr)) return 0; } else { pr->throttling.acpi_processor_get_throttling = &acpi_processor_get_throttling_ptc; pr->throttling.acpi_processor_set_throttling = &acpi_processor_set_throttling_ptc; } /* * If TSD package for one CPU can't be parsed successfully, it means * that this CPU will have no coordination with other CPUs. */ if (acpi_processor_get_tsd(pr)) { pthrottling = &pr->throttling; pthrottling->tsd_valid_flag = 0; cpumask_set_cpu(pr->id, pthrottling->shared_cpu_map); pthrottling->shared_type = DOMAIN_COORD_TYPE_SW_ALL; } /* * 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; } 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, false); if (result) goto end; } end: if (result) pr->flags.throttling = 0; return result; }