Add the rt linux 4.1.3-rt3 as base
[kvmfornfv.git] / kernel / drivers / acpi / processor_throttling.c
diff --git a/kernel/drivers/acpi/processor_throttling.c b/kernel/drivers/acpi/processor_throttling.c
new file mode 100644 (file)
index 0000000..84243c3
--- /dev/null
@@ -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;
+}
+