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authorAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-08-05 17:04:01 -0300
committerAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-08-05 17:04:01 -0300
commit57f0f512b273f60d52568b8c6b77e17f5636edc0 (patch)
tree5e910f0e82173f4ef4f51111366a3f1299037a7b /drivers/acpi/processor_throttling.c
Initial import
Diffstat (limited to 'drivers/acpi/processor_throttling.c')
-rw-r--r--drivers/acpi/processor_throttling.c1264
1 files changed, 1264 insertions, 0 deletions
diff --git a/drivers/acpi/processor_throttling.c b/drivers/acpi/processor_throttling.c
new file mode 100644
index 000000000..84243c32e
--- /dev/null
+++ b/drivers/acpi/processor_throttling.c
@@ -0,0 +1,1264 @@
+/*
+ * 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 <linux/acpi.h>
+#include <acpi/processor.h>
+#include <asm/io.h>
+#include <asm/uaccess.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 */
+};
+
+struct acpi_processor_throttling_arg {
+ struct acpi_processor *pr;
+ int target_state;
+ bool force;
+};
+
+#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, &current->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;
+}
+
+static long acpi_processor_throttling_fn(void *data)
+{
+ struct acpi_processor_throttling_arg *arg = data;
+ struct acpi_processor *pr = arg->pr;
+
+ return pr->throttling.acpi_processor_set_throttling(pr,
+ arg->target_state, arg->force);
+}
+
+int acpi_processor_set_throttling(struct acpi_processor *pr,
+ int state, bool force)
+{
+ int ret = 0;
+ unsigned int i;
+ struct acpi_processor *match_pr;
+ struct acpi_processor_throttling *p_throttling;
+ struct acpi_processor_throttling_arg arg;
+ struct throttling_tstate t_state;
+
+ if (!pr)
+ return -EINVAL;
+
+ if (!pr->flags.throttling)
+ return -ENODEV;
+
+ if ((state < 0) || (state > (pr->throttling.state_count - 1)))
+ return -EINVAL;
+
+ if (cpu_is_offline(pr->id)) {
+ /*
+ * the cpu pointed by pr->id is offline. Unnecessary to change
+ * the throttling state any more.
+ */
+ return -ENODEV;
+ }
+
+ t_state.target_state = state;
+ p_throttling = &(pr->throttling);
+
+ /*
+ * 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_and(i, cpu_online_mask, p_throttling->shared_cpu_map) {
+ 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) {
+ arg.pr = pr;
+ arg.target_state = state;
+ arg.force = force;
+ ret = work_on_cpu(pr->id, acpi_processor_throttling_fn, &arg);
+ } 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_and(i, cpu_online_mask,
+ p_throttling->shared_cpu_map) {
+ 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;
+ }
+
+ arg.pr = match_pr;
+ arg.target_state = state;
+ arg.force = force;
+ ret = work_on_cpu(pr->id, acpi_processor_throttling_fn,
+ &arg);
+ }
+ }
+ /*
+ * 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_and(i, cpu_online_mask, p_throttling->shared_cpu_map) {
+ t_state.cpu = i;
+ acpi_processor_throttling_notifier(THROTTLING_POSTCHANGE,
+ &t_state);
+ }
+
+ 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;
+}
+