Initial import

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;
+}
+