drivers/acpi/processor_perflib.c - kernel/msm - Gitiles

 /*
  * processor_perflib.c - ACPI Processor P-States Library ($Revision: 71 $)
  *
  *  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/init.h>
 #include <linux/cpufreq.h>

 #ifdef CONFIG_X86_ACPI_CPUFREQ_PROC_INTF
 #include <linux/proc_fs.h>
 #include <linux/seq_file.h>
 #include <linux/mutex.h>

 #include <asm/uaccess.h>
 #endif

 #include <acpi/acpi_bus.h>
 #include <acpi/processor.h>

 #define ACPI_PROCESSOR_COMPONENT	0x01000000
 #define ACPI_PROCESSOR_CLASS		"processor"
 #define ACPI_PROCESSOR_FILE_PERFORMANCE	"performance"
 #define _COMPONENT		ACPI_PROCESSOR_COMPONENT
 ACPI_MODULE_NAME("processor_perflib");

 static DEFINE_MUTEX(performance_mutex);

 /*
  * _PPC support is implemented as a CPUfreq policy notifier:
  * This means each time a CPUfreq driver registered also with
  * the ACPI core is asked to change the speed policy, the maximum
  * value is adjusted so that it is within the platform limit.
  *
  * Also, when a new platform limit value is detected, the CPUfreq
  * policy is adjusted accordingly.
  */

 #define PPC_REGISTERED   1
 #define PPC_IN_USE       2

 static int acpi_processor_ppc_status = 0;

 static int acpi_processor_ppc_notifier(struct notifier_block *nb,
 				       unsigned long event, void *data)
 {
 	struct cpufreq_policy *policy = data;
 	struct acpi_processor *pr;
 	unsigned int ppc = 0;

 	mutex_lock(&performance_mutex);

 	if (event != CPUFREQ_INCOMPATIBLE)
 		goto out;

 	pr = processors[policy->cpu];
 	if (!pr || !pr->performance)
 		goto out;

 	ppc = (unsigned int)pr->performance_platform_limit;

 	if (ppc >= pr->performance->state_count)
 		goto out;

 	cpufreq_verify_within_limits(policy, 0,
 				     pr->performance->states[ppc].
 				     core_frequency * 1000);

       out:
 	mutex_unlock(&performance_mutex);

 	return 0;
 }

 static struct notifier_block acpi_ppc_notifier_block = {
 	.notifier_call = acpi_processor_ppc_notifier,
 };

 static int acpi_processor_get_platform_limit(struct acpi_processor *pr)
 {
 	acpi_status status = 0;
 	unsigned long ppc = 0;


 	if (!pr)
 		return -EINVAL;

 	/*
 	 * _PPC indicates the maximum state currently supported by the platform
 	 * (e.g. 0 = states 0..n; 1 = states 1..n; etc.
 	 */
 	status = acpi_evaluate_integer(pr->handle, "_PPC", NULL, &ppc);

 	if (status != AE_NOT_FOUND)
 		acpi_processor_ppc_status |= PPC_IN_USE;

 	if (ACPI_FAILURE(status) && status != AE_NOT_FOUND) {
 		ACPI_EXCEPTION((AE_INFO, status, "Evaluating _PPC"));
 		return -ENODEV;
 	}

 	pr->performance_platform_limit = (int)ppc;

 	return 0;
 }

 int acpi_processor_ppc_has_changed(struct acpi_processor *pr)
 {
 	int ret = acpi_processor_get_platform_limit(pr);
 	if (ret < 0)
 		return (ret);
 	else
 		return cpufreq_update_policy(pr->id);
 }

 void acpi_processor_ppc_init(void)
 {
 	if (!cpufreq_register_notifier
 	    (&acpi_ppc_notifier_block, CPUFREQ_POLICY_NOTIFIER))
 		acpi_processor_ppc_status |= PPC_REGISTERED;
 	else
 		printk(KERN_DEBUG
 		       "Warning: Processor Platform Limit not supported.\n");
 }

 void acpi_processor_ppc_exit(void)
 {
 	if (acpi_processor_ppc_status & PPC_REGISTERED)
 		cpufreq_unregister_notifier(&acpi_ppc_notifier_block,
 					    CPUFREQ_POLICY_NOTIFIER);

 	acpi_processor_ppc_status &= ~PPC_REGISTERED;
 }

 static int acpi_processor_get_performance_control(struct acpi_processor *pr)
 {
 	int result = 0;
 	acpi_status status = 0;
 	struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
 	union acpi_object *pct = NULL;
 	union acpi_object obj = { 0 };


 	status = acpi_evaluate_object(pr->handle, "_PCT", NULL, &buffer);
 	if (ACPI_FAILURE(status)) {
 		ACPI_EXCEPTION((AE_INFO, status, "Evaluating _PCT"));
 		return -ENODEV;
 	}

 	pct = (union acpi_object *)buffer.pointer;
 	if (!pct || (pct->type != ACPI_TYPE_PACKAGE)
 	    || (pct->package.count != 2)) {
 		printk(KERN_ERR PREFIX "Invalid _PCT data\n");
 		result = -EFAULT;
 		goto end;
 	}

 	/*
 	 * control_register
 	 */

 	obj = pct->package.elements[0];

 	if ((obj.type != ACPI_TYPE_BUFFER)
 	    || (obj.buffer.length < sizeof(struct acpi_pct_register))
 	    || (obj.buffer.pointer == NULL)) {
 		printk(KERN_ERR PREFIX "Invalid _PCT data (control_register)\n");
 		result = -EFAULT;
 		goto end;
 	}
 	memcpy(&pr->performance->control_register, obj.buffer.pointer,
 	       sizeof(struct acpi_pct_register));

 	/*
 	 * status_register
 	 */

 	obj = pct->package.elements[1];

 	if ((obj.type != ACPI_TYPE_BUFFER)
 	    || (obj.buffer.length < sizeof(struct acpi_pct_register))
 	    || (obj.buffer.pointer == NULL)) {
 		printk(KERN_ERR PREFIX "Invalid _PCT data (status_register)\n");
 		result = -EFAULT;
 		goto end;
 	}

 	memcpy(&pr->performance->status_register, obj.buffer.pointer,
 	       sizeof(struct acpi_pct_register));

       end:
 	kfree(buffer.pointer);

 	return result;
 }

 static int acpi_processor_get_performance_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("NNNNNN"), "NNNNNN" };
 	struct acpi_buffer state = { 0, NULL };
 	union acpi_object *pss = NULL;
 	int i;


 	status = acpi_evaluate_object(pr->handle, "_PSS", NULL, &buffer);
 	if (ACPI_FAILURE(status)) {
 		ACPI_EXCEPTION((AE_INFO, status, "Evaluating _PSS"));
 		return -ENODEV;
 	}

 	pss = buffer.pointer;
 	if (!pss || (pss->type != ACPI_TYPE_PACKAGE)) {
 		printk(KERN_ERR PREFIX "Invalid _PSS data\n");
 		result = -EFAULT;
 		goto end;
 	}

 	ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found %d performance states\n",
 			  pss->package.count));

 	pr->performance->state_count = pss->package.count;
 	pr->performance->states =
 	    kmalloc(sizeof(struct acpi_processor_px) * pss->package.count,
 		    GFP_KERNEL);
 	if (!pr->performance->states) {
 		result = -ENOMEM;
 		goto end;
 	}

 	for (i = 0; i < pr->performance->state_count; i++) {

 		struct acpi_processor_px *px = &(pr->performance->states[i]);

 		state.length = sizeof(struct acpi_processor_px);
 		state.pointer = px;

 		ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Extracting state %d\n", i));

 		status = acpi_extract_package(&(pss->package.elements[i]),
 					      &format, &state);
 		if (ACPI_FAILURE(status)) {
 			ACPI_EXCEPTION((AE_INFO, status, "Invalid _PSS data"));
 			result = -EFAULT;
 			kfree(pr->performance->states);
 			goto end;
 		}

 		ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 				  "State [%d]: core_frequency[%d] power[%d] transition_latency[%d] bus_master_latency[%d] control[0x%x] status[0x%x]\n",
 				  i,
 				  (u32) px->core_frequency,
 				  (u32) px->power,
 				  (u32) px->transition_latency,
 				  (u32) px->bus_master_latency,
 				  (u32) px->control, (u32) px->status));

 		if (!px->core_frequency) {
 			printk(KERN_ERR PREFIX
 				    "Invalid _PSS data: freq is zero\n");
 			result = -EFAULT;
 			kfree(pr->performance->states);
 			goto end;
 		}
 	}

       end:
 	kfree(buffer.pointer);

 	return result;
 }

 static int acpi_processor_get_performance_info(struct acpi_processor *pr)
 {
 	int result = 0;
 	acpi_status status = AE_OK;
 	acpi_handle handle = NULL;


 	if (!pr || !pr->performance || !pr->handle)
 		return -EINVAL;

 	status = acpi_get_handle(pr->handle, "_PCT", &handle);
 	if (ACPI_FAILURE(status)) {
 		ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 				  "ACPI-based processor performance control unavailable\n"));
 		return -ENODEV;
 	}

 	result = acpi_processor_get_performance_control(pr);
 	if (result)
 		return result;

 	result = acpi_processor_get_performance_states(pr);
 	if (result)
 		return result;

 	return 0;
 }

 int acpi_processor_notify_smm(struct module *calling_module)
 {
 	acpi_status status;
 	static int is_done = 0;


 	if (!(acpi_processor_ppc_status & PPC_REGISTERED))
 		return -EBUSY;

 	if (!try_module_get(calling_module))
 		return -EINVAL;

 	/* is_done is set to negative if an error occured,
 	 * and to postitive if _no_ error occured, but SMM
 	 * was already notified. This avoids double notification
 	 * which might lead to unexpected results...
 	 */
 	if (is_done > 0) {
 		module_put(calling_module);
 		return 0;
 	} else if (is_done < 0) {
 		module_put(calling_module);
 		return is_done;
 	}

 	is_done = -EIO;

 	/* Can't write pstate_control to smi_command if either value is zero */
 	if ((!acpi_gbl_FADT.smi_command) || (!acpi_gbl_FADT.pstate_control)) {
 		ACPI_DEBUG_PRINT((ACPI_DB_INFO, "No SMI port or pstate_control\n"));
 		module_put(calling_module);
 		return 0;
 	}

 	ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 			  "Writing pstate_control [0x%x] to smi_command [0x%x]\n",
 			  acpi_gbl_FADT.pstate_control, acpi_gbl_FADT.smi_command));

 	status = acpi_os_write_port(acpi_gbl_FADT.smi_command,
 				    (u32) acpi_gbl_FADT.pstate_control, 8);
 	if (ACPI_FAILURE(status)) {
 		ACPI_EXCEPTION((AE_INFO, status,
 				"Failed to write pstate_control [0x%x] to "
 				"smi_command [0x%x]", acpi_gbl_FADT.pstate_control,
 				acpi_gbl_FADT.smi_command));
 		module_put(calling_module);
 		return status;
 	}

 	/* Success. If there's no _PPC, we need to fear nothing, so
 	 * we can allow the cpufreq driver to be rmmod'ed. */
 	is_done = 1;

 	if (!(acpi_processor_ppc_status & PPC_IN_USE))
 		module_put(calling_module);

 	return 0;
 }

 EXPORT_SYMBOL(acpi_processor_notify_smm);

 #ifdef CONFIG_X86_ACPI_CPUFREQ_PROC_INTF
 /* /proc/acpi/processor/../performance interface (DEPRECATED) */

 static int acpi_processor_perf_open_fs(struct inode *inode, struct file *file);
 static struct file_operations acpi_processor_perf_fops = {
 	.open = acpi_processor_perf_open_fs,
 	.read = seq_read,
 	.llseek = seq_lseek,
 	.release = single_release,
 };

 static int acpi_processor_perf_seq_show(struct seq_file *seq, void *offset)
 {
 	struct acpi_processor *pr = seq->private;
 	int i;


 	if (!pr)
 		goto end;

 	if (!pr->performance) {
 		seq_puts(seq, "<not supported>\n");
 		goto end;
 	}

 	seq_printf(seq, "state count:             %d\n"
 		   "active state:            P%d\n",
 		   pr->performance->state_count, pr->performance->state);

 	seq_puts(seq, "states:\n");
 	for (i = 0; i < pr->performance->state_count; i++)
 		seq_printf(seq,
 			   "   %cP%d:                  %d MHz, %d mW, %d uS\n",
 			   (i == pr->performance->state ? '*' : ' '), i,
 			   (u32) pr->performance->states[i].core_frequency,
 			   (u32) pr->performance->states[i].power,
 			   (u32) pr->performance->states[i].transition_latency);

       end:
 	return 0;
 }

 static int acpi_processor_perf_open_fs(struct inode *inode, struct file *file)
 {
 	return single_open(file, acpi_processor_perf_seq_show,
 			   PDE(inode)->data);
 }

 static void acpi_cpufreq_add_file(struct acpi_processor *pr)
 {
 	struct proc_dir_entry *entry = NULL;
 	struct acpi_device *device = NULL;


 	if (acpi_bus_get_device(pr->handle, &device))
 		return;

 	/* add file 'performance' [R/W] */
 	entry = create_proc_entry(ACPI_PROCESSOR_FILE_PERFORMANCE,
 				  S_IFREG | S_IRUGO,
 				  acpi_device_dir(device));
 	if (entry){
 		entry->proc_fops = &acpi_processor_perf_fops;
 		entry->data = acpi_driver_data(device);
 		entry->owner = THIS_MODULE;
 	}
 	return;
 }

 static void acpi_cpufreq_remove_file(struct acpi_processor *pr)
 {
 	struct acpi_device *device = NULL;


 	if (acpi_bus_get_device(pr->handle, &device))
 		return;

 	/* remove file 'performance' */
 	remove_proc_entry(ACPI_PROCESSOR_FILE_PERFORMANCE,
 			  acpi_device_dir(device));

 	return;
 }

 #else
 static void acpi_cpufreq_add_file(struct acpi_processor *pr)
 {
 	return;
 }
 static void acpi_cpufreq_remove_file(struct acpi_processor *pr)
 {
 	return;
 }
 #endif				/* CONFIG_X86_ACPI_CPUFREQ_PROC_INTF */

 static int acpi_processor_get_psd(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  *psd = NULL;
 	struct acpi_psd_package *pdomain;

 	status = acpi_evaluate_object(pr->handle, "_PSD", NULL, &buffer);
 	if (ACPI_FAILURE(status)) {
 		return -ENODEV;
 	}

 	psd = buffer.pointer;
 	if (!psd || (psd->type != ACPI_TYPE_PACKAGE)) {
 		ACPI_DEBUG_PRINT((ACPI_DB_ERROR, "Invalid _PSD data\n"));
 		result = -EFAULT;
 		goto end;
 	}

 	if (psd->package.count != 1) {
 		ACPI_DEBUG_PRINT((ACPI_DB_ERROR, "Invalid _PSD data\n"));
 		result = -EFAULT;
 		goto end;
 	}

 	pdomain = &(pr->performance->domain_info);

 	state.length = sizeof(struct acpi_psd_package);
 	state.pointer = pdomain;

 	status = acpi_extract_package(&(psd->package.elements[0]),
 		&format, &state);
 	if (ACPI_FAILURE(status)) {
 		ACPI_DEBUG_PRINT((ACPI_DB_ERROR, "Invalid _PSD data\n"));
 		result = -EFAULT;
 		goto end;
 	}

 	if (pdomain->num_entries != ACPI_PSD_REV0_ENTRIES) {
 		ACPI_DEBUG_PRINT((ACPI_DB_ERROR, "Unknown _PSD:num_entries\n"));
 		result = -EFAULT;
 		goto end;
 	}

 	if (pdomain->revision != ACPI_PSD_REV0_REVISION) {
 		ACPI_DEBUG_PRINT((ACPI_DB_ERROR, "Unknown _PSD:revision\n"));
 		result = -EFAULT;
 		goto end;
 	}

 end:
 	kfree(buffer.pointer);
 	return result;
 }

 int acpi_processor_preregister_performance(
 		struct acpi_processor_performance *performance)
 {
 	int count, count_target;
 	int retval = 0;
 	unsigned int i, j;
 	cpumask_t covered_cpus;
 	struct acpi_processor *pr;
 	struct acpi_psd_package *pdomain;
 	struct acpi_processor *match_pr;
 	struct acpi_psd_package *match_pdomain;

 	mutex_lock(&performance_mutex);

 	retval = 0;

 	/* Call _PSD for all CPUs */
 	for_each_possible_cpu(i) {
 		pr = processors[i];
 		if (!pr) {
 			/* Look only at processors in ACPI namespace */
 			continue;
 		}

 		if (pr->performance) {
 			retval = -EBUSY;
 			continue;
 		}

 		if (!performance || !percpu_ptr(performance, i)) {
 			retval = -EINVAL;
 			continue;
 		}

 		pr->performance = percpu_ptr(performance, i);
 		cpu_set(i, pr->performance->shared_cpu_map);
 		if (acpi_processor_get_psd(pr)) {
 			retval = -EINVAL;
 			continue;
 		}
 	}
 	if (retval)
 		goto err_ret;

 	/*
 	 * Now that we have _PSD data from all CPUs, lets setup P-state
 	 * domain info.
 	 */
 	for_each_possible_cpu(i) {
 		pr = processors[i];
 		if (!pr)
 			continue;

 		/* Basic validity check for domain info */
 		pdomain = &(pr->performance->domain_info);
 		if ((pdomain->revision != ACPI_PSD_REV0_REVISION) ||
 		    (pdomain->num_entries != ACPI_PSD_REV0_ENTRIES)) {
 			retval = -EINVAL;
 			goto err_ret;
 		}
 		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) {
 			retval = -EINVAL;
 			goto err_ret;
 		}
 	}

 	cpus_clear(covered_cpus);
 	for_each_possible_cpu(i) {
 		pr = processors[i];
 		if (!pr)
 			continue;

 		if (cpu_isset(i, covered_cpus))
 			continue;

 		pdomain = &(pr->performance->domain_info);
 		cpu_set(i, pr->performance->shared_cpu_map);
 		cpu_set(i, covered_cpus);
 		if (pdomain->num_processors <= 1)
 			continue;

 		/* Validate the Domain info */
 		count_target = pdomain->num_processors;
 		count = 1;
 		if (pdomain->coord_type == DOMAIN_COORD_TYPE_SW_ALL)
 			pr->performance->shared_type = CPUFREQ_SHARED_TYPE_ALL;
 		else if (pdomain->coord_type == DOMAIN_COORD_TYPE_HW_ALL)
 			pr->performance->shared_type = CPUFREQ_SHARED_TYPE_HW;
 		else if (pdomain->coord_type == DOMAIN_COORD_TYPE_SW_ANY)
 			pr->performance->shared_type = CPUFREQ_SHARED_TYPE_ANY;

 		for_each_possible_cpu(j) {
 			if (i == j)
 				continue;

 			match_pr = processors[j];
 			if (!match_pr)
 				continue;

 			match_pdomain = &(match_pr->performance->domain_info);
 			if (match_pdomain->domain != pdomain->domain)
 				continue;

 			/* Here i and j are in the same domain */

 			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;
 			}

 			cpu_set(j, covered_cpus);
 			cpu_set(j, pr->performance->shared_cpu_map);
 			count++;
 		}

 		for_each_possible_cpu(j) {
 			if (i == j)
 				continue;

 			match_pr = processors[j];
 			if (!match_pr)
 				continue;

 			match_pdomain = &(match_pr->performance->domain_info);
 			if (match_pdomain->domain != pdomain->domain)
 				continue;

 			match_pr->performance->shared_type =
 					pr->performance->shared_type;
 			match_pr->performance->shared_cpu_map =
 				pr->performance->shared_cpu_map;
 		}
 	}

 err_ret:
 	for_each_possible_cpu(i) {
 		pr = processors[i];
 		if (!pr || !pr->performance)
 			continue;

 		/* Assume no coordination on any error parsing domain info */
 		if (retval) {
 			cpus_clear(pr->performance->shared_cpu_map);
 			cpu_set(i, pr->performance->shared_cpu_map);
 			pr->performance->shared_type = CPUFREQ_SHARED_TYPE_ALL;
 		}
 		pr->performance = NULL; /* Will be set for real in register */
 	}

 	mutex_unlock(&performance_mutex);
 	return retval;
 }
 EXPORT_SYMBOL(acpi_processor_preregister_performance);


 int
 acpi_processor_register_performance(struct acpi_processor_performance
 				    *performance, unsigned int cpu)
 {
 	struct acpi_processor *pr;


 	if (!(acpi_processor_ppc_status & PPC_REGISTERED))
 		return -EINVAL;

 	mutex_lock(&performance_mutex);

 	pr = processors[cpu];
 	if (!pr) {
 		mutex_unlock(&performance_mutex);
 		return -ENODEV;
 	}

 	if (pr->performance) {
 		mutex_unlock(&performance_mutex);
 		return -EBUSY;
 	}

 	WARN_ON(!performance);

 	pr->performance = performance;

 	if (acpi_processor_get_performance_info(pr)) {
 		pr->performance = NULL;
 		mutex_unlock(&performance_mutex);
 		return -EIO;
 	}

 	acpi_cpufreq_add_file(pr);

 	mutex_unlock(&performance_mutex);
 	return 0;
 }

 EXPORT_SYMBOL(acpi_processor_register_performance);

 void
 acpi_processor_unregister_performance(struct acpi_processor_performance
 				      *performance, unsigned int cpu)
 {
 	struct acpi_processor *pr;


 	mutex_lock(&performance_mutex);

 	pr = processors[cpu];
 	if (!pr) {
 		mutex_unlock(&performance_mutex);
 		return;
 	}

 	if (pr->performance)
 		kfree(pr->performance->states);
 	pr->performance = NULL;

 	acpi_cpufreq_remove_file(pr);

 	mutex_unlock(&performance_mutex);

 	return;
 }

 EXPORT_SYMBOL(acpi_processor_unregister_performance);
	/*
	* processor_perflib.c - ACPI Processor P-States Library ($Revision: 71 $)
	*
	* 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/init.h>
	#include <linux/cpufreq.h>

	#ifdef CONFIG_X86_ACPI_CPUFREQ_PROC_INTF
	#include <linux/proc_fs.h>
	#include <linux/seq_file.h>
	#include <linux/mutex.h>

	#include <asm/uaccess.h>
	#endif

	#include <acpi/acpi_bus.h>
	#include <acpi/processor.h>

	#define ACPI_PROCESSOR_COMPONENT 0x01000000
	#define ACPI_PROCESSOR_CLASS "processor"
	#define ACPI_PROCESSOR_FILE_PERFORMANCE "performance"
	#define _COMPONENT ACPI_PROCESSOR_COMPONENT
	ACPI_MODULE_NAME("processor_perflib");

	static DEFINE_MUTEX(performance_mutex);

	/*
	* _PPC support is implemented as a CPUfreq policy notifier:
	* This means each time a CPUfreq driver registered also with
	* the ACPI core is asked to change the speed policy, the maximum
	* value is adjusted so that it is within the platform limit.
	*
	* Also, when a new platform limit value is detected, the CPUfreq
	* policy is adjusted accordingly.
	*/

	#define PPC_REGISTERED 1
	#define PPC_IN_USE 2

	static int acpi_processor_ppc_status = 0;

	static int acpi_processor_ppc_notifier(struct notifier_block *nb,
	unsigned long event, void *data)
	{
	struct cpufreq_policy *policy = data;
	struct acpi_processor *pr;
	unsigned int ppc = 0;

	mutex_lock(&performance_mutex);

	if (event != CPUFREQ_INCOMPATIBLE)
	goto out;

	pr = processors[policy->cpu];
	if (!pr \|\| !pr->performance)
	goto out;

	ppc = (unsigned int)pr->performance_platform_limit;

	if (ppc >= pr->performance->state_count)
	goto out;

	cpufreq_verify_within_limits(policy, 0,
	pr->performance->states[ppc].
	core_frequency * 1000);

	out:
	mutex_unlock(&performance_mutex);

	return 0;
	}

	static struct notifier_block acpi_ppc_notifier_block = {
	.notifier_call = acpi_processor_ppc_notifier,
	};

	static int acpi_processor_get_platform_limit(struct acpi_processor *pr)
	{
	acpi_status status = 0;
	unsigned long ppc = 0;


	if (!pr)
	return -EINVAL;

	/*
	* _PPC indicates the maximum state currently supported by the platform
	* (e.g. 0 = states 0..n; 1 = states 1..n; etc.
	*/
	status = acpi_evaluate_integer(pr->handle, "_PPC", NULL, &ppc);

	if (status != AE_NOT_FOUND)
	acpi_processor_ppc_status \|= PPC_IN_USE;

	if (ACPI_FAILURE(status) && status != AE_NOT_FOUND) {
	ACPI_EXCEPTION((AE_INFO, status, "Evaluating _PPC"));
	return -ENODEV;
	}

	pr->performance_platform_limit = (int)ppc;

	return 0;
	}

	int acpi_processor_ppc_has_changed(struct acpi_processor *pr)
	{
	int ret = acpi_processor_get_platform_limit(pr);
	if (ret < 0)
	return (ret);
	else
	return cpufreq_update_policy(pr->id);
	}

	void acpi_processor_ppc_init(void)
	{
	if (!cpufreq_register_notifier
	(&acpi_ppc_notifier_block, CPUFREQ_POLICY_NOTIFIER))
	acpi_processor_ppc_status \|= PPC_REGISTERED;
	else
	printk(KERN_DEBUG
	"Warning: Processor Platform Limit not supported.\n");
	}

	void acpi_processor_ppc_exit(void)
	{
	if (acpi_processor_ppc_status & PPC_REGISTERED)
	cpufreq_unregister_notifier(&acpi_ppc_notifier_block,
	CPUFREQ_POLICY_NOTIFIER);

	acpi_processor_ppc_status &= ~PPC_REGISTERED;
	}

	static int acpi_processor_get_performance_control(struct acpi_processor *pr)
	{
	int result = 0;
	acpi_status status = 0;
	struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
	union acpi_object *pct = NULL;
	union acpi_object obj = { 0 };


	status = acpi_evaluate_object(pr->handle, "_PCT", NULL, &buffer);
	if (ACPI_FAILURE(status)) {
	ACPI_EXCEPTION((AE_INFO, status, "Evaluating _PCT"));
	return -ENODEV;
	}

	pct = (union acpi_object *)buffer.pointer;
	if (!pct \|\| (pct->type != ACPI_TYPE_PACKAGE)
	\|\| (pct->package.count != 2)) {
	printk(KERN_ERR PREFIX "Invalid _PCT data\n");
	result = -EFAULT;
	goto end;
	}

	/*
	* control_register
	*/

	obj = pct->package.elements[0];

	if ((obj.type != ACPI_TYPE_BUFFER)
	\|\| (obj.buffer.length < sizeof(struct acpi_pct_register))
	\|\| (obj.buffer.pointer == NULL)) {
	printk(KERN_ERR PREFIX "Invalid _PCT data (control_register)\n");
	result = -EFAULT;
	goto end;
	}
	memcpy(&pr->performance->control_register, obj.buffer.pointer,
	sizeof(struct acpi_pct_register));

	/*
	* status_register
	*/

	obj = pct->package.elements[1];

	if ((obj.type != ACPI_TYPE_BUFFER)
	\|\| (obj.buffer.length < sizeof(struct acpi_pct_register))
	\|\| (obj.buffer.pointer == NULL)) {
	printk(KERN_ERR PREFIX "Invalid _PCT data (status_register)\n");
	result = -EFAULT;
	goto end;
	}

	memcpy(&pr->performance->status_register, obj.buffer.pointer,
	sizeof(struct acpi_pct_register));

	end:
	kfree(buffer.pointer);

	return result;
	}

	static int acpi_processor_get_performance_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("NNNNNN"), "NNNNNN" };
	struct acpi_buffer state = { 0, NULL };
	union acpi_object *pss = NULL;
	int i;


	status = acpi_evaluate_object(pr->handle, "_PSS", NULL, &buffer);
	if (ACPI_FAILURE(status)) {
	ACPI_EXCEPTION((AE_INFO, status, "Evaluating _PSS"));
	return -ENODEV;
	}

	pss = buffer.pointer;
	if (!pss \|\| (pss->type != ACPI_TYPE_PACKAGE)) {
	printk(KERN_ERR PREFIX "Invalid _PSS data\n");
	result = -EFAULT;
	goto end;
	}

	ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found %d performance states\n",
	pss->package.count));

	pr->performance->state_count = pss->package.count;
	pr->performance->states =
	kmalloc(sizeof(struct acpi_processor_px) * pss->package.count,
	GFP_KERNEL);
	if (!pr->performance->states) {
	result = -ENOMEM;
	goto end;
	}

	for (i = 0; i < pr->performance->state_count; i++) {

	struct acpi_processor_px *px = &(pr->performance->states[i]);

	state.length = sizeof(struct acpi_processor_px);
	state.pointer = px;

	ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Extracting state %d\n", i));

	status = acpi_extract_package(&(pss->package.elements[i]),
	&format, &state);
	if (ACPI_FAILURE(status)) {
	ACPI_EXCEPTION((AE_INFO, status, "Invalid _PSS data"));
	result = -EFAULT;
	kfree(pr->performance->states);
	goto end;
	}

	ACPI_DEBUG_PRINT((ACPI_DB_INFO,
	"State [%d]: core_frequency[%d] power[%d] transition_latency[%d] bus_master_latency[%d] control[0x%x] status[0x%x]\n",
	i,
	(u32) px->core_frequency,
	(u32) px->power,
	(u32) px->transition_latency,
	(u32) px->bus_master_latency,
	(u32) px->control, (u32) px->status));

	if (!px->core_frequency) {
	printk(KERN_ERR PREFIX
	"Invalid _PSS data: freq is zero\n");
	result = -EFAULT;
	kfree(pr->performance->states);
	goto end;
	}
	}

	end:
	kfree(buffer.pointer);

	return result;
	}

	static int acpi_processor_get_performance_info(struct acpi_processor *pr)
	{
	int result = 0;
	acpi_status status = AE_OK;
	acpi_handle handle = NULL;


	if (!pr \|\| !pr->performance \|\| !pr->handle)
	return -EINVAL;

	status = acpi_get_handle(pr->handle, "_PCT", &handle);
	if (ACPI_FAILURE(status)) {
	ACPI_DEBUG_PRINT((ACPI_DB_INFO,
	"ACPI-based processor performance control unavailable\n"));
	return -ENODEV;
	}

	result = acpi_processor_get_performance_control(pr);
	if (result)
	return result;

	result = acpi_processor_get_performance_states(pr);
	if (result)
	return result;

	return 0;
	}

	int acpi_processor_notify_smm(struct module *calling_module)
	{
	acpi_status status;
	static int is_done = 0;


	if (!(acpi_processor_ppc_status & PPC_REGISTERED))
	return -EBUSY;

	if (!try_module_get(calling_module))
	return -EINVAL;

	/* is_done is set to negative if an error occured,
	* and to postitive if _no_ error occured, but SMM
	* was already notified. This avoids double notification
	* which might lead to unexpected results...
	*/
	if (is_done > 0) {
	module_put(calling_module);
	return 0;
	} else if (is_done < 0) {
	module_put(calling_module);
	return is_done;
	}

	is_done = -EIO;

	/* Can't write pstate_control to smi_command if either value is zero */
	if ((!acpi_gbl_FADT.smi_command) \|\| (!acpi_gbl_FADT.pstate_control)) {
	ACPI_DEBUG_PRINT((ACPI_DB_INFO, "No SMI port or pstate_control\n"));
	module_put(calling_module);
	return 0;
	}

	ACPI_DEBUG_PRINT((ACPI_DB_INFO,
	"Writing pstate_control [0x%x] to smi_command [0x%x]\n",
	acpi_gbl_FADT.pstate_control, acpi_gbl_FADT.smi_command));

	status = acpi_os_write_port(acpi_gbl_FADT.smi_command,
	(u32) acpi_gbl_FADT.pstate_control, 8);
	if (ACPI_FAILURE(status)) {
	ACPI_EXCEPTION((AE_INFO, status,
	"Failed to write pstate_control [0x%x] to "
	"smi_command [0x%x]", acpi_gbl_FADT.pstate_control,
	acpi_gbl_FADT.smi_command));
	module_put(calling_module);
	return status;
	}

	/* Success. If there's no _PPC, we need to fear nothing, so
	* we can allow the cpufreq driver to be rmmod'ed. */
	is_done = 1;

	if (!(acpi_processor_ppc_status & PPC_IN_USE))
	module_put(calling_module);

	return 0;
	}

	EXPORT_SYMBOL(acpi_processor_notify_smm);

	#ifdef CONFIG_X86_ACPI_CPUFREQ_PROC_INTF
	/* /proc/acpi/processor/../performance interface (DEPRECATED) */

	static int acpi_processor_perf_open_fs(struct inode inode, struct file file);
	static struct file_operations acpi_processor_perf_fops = {
	.open = acpi_processor_perf_open_fs,
	.read = seq_read,
	.llseek = seq_lseek,
	.release = single_release,
	};

	static int acpi_processor_perf_seq_show(struct seq_file seq, void offset)
	{
	struct acpi_processor *pr = seq->private;
	int i;


	if (!pr)
	goto end;

	if (!pr->performance) {
	seq_puts(seq, "<not supported>\n");
	goto end;
	}

	seq_printf(seq, "state count: %d\n"
	"active state: P%d\n",
	pr->performance->state_count, pr->performance->state);

	seq_puts(seq, "states:\n");
	for (i = 0; i < pr->performance->state_count; i++)
	seq_printf(seq,
	" %cP%d: %d MHz, %d mW, %d uS\n",
	(i == pr->performance->state ? '*' : ' '), i,
	(u32) pr->performance->states[i].core_frequency,
	(u32) pr->performance->states[i].power,
	(u32) pr->performance->states[i].transition_latency);

	end:
	return 0;
	}

	static int acpi_processor_perf_open_fs(struct inode inode, struct file file)
	{
	return single_open(file, acpi_processor_perf_seq_show,
	PDE(inode)->data);
	}

	static void acpi_cpufreq_add_file(struct acpi_processor *pr)
	{
	struct proc_dir_entry *entry = NULL;
	struct acpi_device *device = NULL;


	if (acpi_bus_get_device(pr->handle, &device))
	return;

	/* add file 'performance' [R/W] */
	entry = create_proc_entry(ACPI_PROCESSOR_FILE_PERFORMANCE,
	S_IFREG \| S_IRUGO,
	acpi_device_dir(device));
	if (entry){
	entry->proc_fops = &acpi_processor_perf_fops;
	entry->data = acpi_driver_data(device);
	entry->owner = THIS_MODULE;
	}
	return;
	}

	static void acpi_cpufreq_remove_file(struct acpi_processor *pr)
	{
	struct acpi_device *device = NULL;


	if (acpi_bus_get_device(pr->handle, &device))
	return;

	/* remove file 'performance' */
	remove_proc_entry(ACPI_PROCESSOR_FILE_PERFORMANCE,
	acpi_device_dir(device));

	return;
	}

	#else
	static void acpi_cpufreq_add_file(struct acpi_processor *pr)
	{
	return;
	}
	static void acpi_cpufreq_remove_file(struct acpi_processor *pr)
	{
	return;
	}
	#endif /* CONFIG_X86_ACPI_CPUFREQ_PROC_INTF */

	static int acpi_processor_get_psd(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 *psd = NULL;
	struct acpi_psd_package *pdomain;

	status = acpi_evaluate_object(pr->handle, "_PSD", NULL, &buffer);
	if (ACPI_FAILURE(status)) {
	return -ENODEV;
	}

	psd = buffer.pointer;
	if (!psd \|\| (psd->type != ACPI_TYPE_PACKAGE)) {
	ACPI_DEBUG_PRINT((ACPI_DB_ERROR, "Invalid _PSD data\n"));
	result = -EFAULT;
	goto end;
	}

	if (psd->package.count != 1) {
	ACPI_DEBUG_PRINT((ACPI_DB_ERROR, "Invalid _PSD data\n"));
	result = -EFAULT;
	goto end;
	}

	pdomain = &(pr->performance->domain_info);

	state.length = sizeof(struct acpi_psd_package);
	state.pointer = pdomain;

	status = acpi_extract_package(&(psd->package.elements[0]),
	&format, &state);
	if (ACPI_FAILURE(status)) {
	ACPI_DEBUG_PRINT((ACPI_DB_ERROR, "Invalid _PSD data\n"));
	result = -EFAULT;
	goto end;
	}

	if (pdomain->num_entries != ACPI_PSD_REV0_ENTRIES) {
	ACPI_DEBUG_PRINT((ACPI_DB_ERROR, "Unknown _PSD:num_entries\n"));
	result = -EFAULT;
	goto end;
	}

	if (pdomain->revision != ACPI_PSD_REV0_REVISION) {
	ACPI_DEBUG_PRINT((ACPI_DB_ERROR, "Unknown _PSD:revision\n"));
	result = -EFAULT;
	goto end;
	}

	end:
	kfree(buffer.pointer);
	return result;
	}

	int acpi_processor_preregister_performance(
	struct acpi_processor_performance *performance)
	{
	int count, count_target;
	int retval = 0;
	unsigned int i, j;
	cpumask_t covered_cpus;
	struct acpi_processor *pr;
	struct acpi_psd_package *pdomain;
	struct acpi_processor *match_pr;
	struct acpi_psd_package *match_pdomain;

	mutex_lock(&performance_mutex);

	retval = 0;

	/* Call _PSD for all CPUs */
	for_each_possible_cpu(i) {
	pr = processors[i];
	if (!pr) {
	/* Look only at processors in ACPI namespace */
	continue;
	}

	if (pr->performance) {
	retval = -EBUSY;
	continue;
	}

	if (!performance \|\| !percpu_ptr(performance, i)) {
	retval = -EINVAL;
	continue;
	}

	pr->performance = percpu_ptr(performance, i);
	cpu_set(i, pr->performance->shared_cpu_map);
	if (acpi_processor_get_psd(pr)) {
	retval = -EINVAL;
	continue;
	}
	}
	if (retval)
	goto err_ret;

	/*
	* Now that we have _PSD data from all CPUs, lets setup P-state
	* domain info.
	*/
	for_each_possible_cpu(i) {
	pr = processors[i];
	if (!pr)
	continue;

	/* Basic validity check for domain info */
	pdomain = &(pr->performance->domain_info);
	if ((pdomain->revision != ACPI_PSD_REV0_REVISION) \|\|
	(pdomain->num_entries != ACPI_PSD_REV0_ENTRIES)) {
	retval = -EINVAL;
	goto err_ret;
	}
	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) {
	retval = -EINVAL;
	goto err_ret;
	}
	}

	cpus_clear(covered_cpus);
	for_each_possible_cpu(i) {
	pr = processors[i];
	if (!pr)
	continue;

	if (cpu_isset(i, covered_cpus))
	continue;

	pdomain = &(pr->performance->domain_info);
	cpu_set(i, pr->performance->shared_cpu_map);
	cpu_set(i, covered_cpus);
	if (pdomain->num_processors <= 1)
	continue;

	/* Validate the Domain info */
	count_target = pdomain->num_processors;
	count = 1;
	if (pdomain->coord_type == DOMAIN_COORD_TYPE_SW_ALL)
	pr->performance->shared_type = CPUFREQ_SHARED_TYPE_ALL;
	else if (pdomain->coord_type == DOMAIN_COORD_TYPE_HW_ALL)
	pr->performance->shared_type = CPUFREQ_SHARED_TYPE_HW;
	else if (pdomain->coord_type == DOMAIN_COORD_TYPE_SW_ANY)
	pr->performance->shared_type = CPUFREQ_SHARED_TYPE_ANY;

	for_each_possible_cpu(j) {
	if (i == j)
	continue;

	match_pr = processors[j];
	if (!match_pr)
	continue;

	match_pdomain = &(match_pr->performance->domain_info);
	if (match_pdomain->domain != pdomain->domain)
	continue;

	/* Here i and j are in the same domain */

	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;
	}

	cpu_set(j, covered_cpus);
	cpu_set(j, pr->performance->shared_cpu_map);
	count++;
	}

	for_each_possible_cpu(j) {
	if (i == j)
	continue;

	match_pr = processors[j];
	if (!match_pr)
	continue;

	match_pdomain = &(match_pr->performance->domain_info);
	if (match_pdomain->domain != pdomain->domain)
	continue;

	match_pr->performance->shared_type =
	pr->performance->shared_type;
	match_pr->performance->shared_cpu_map =
	pr->performance->shared_cpu_map;
	}
	}

	err_ret:
	for_each_possible_cpu(i) {
	pr = processors[i];
	if (!pr \|\| !pr->performance)
	continue;

	/* Assume no coordination on any error parsing domain info */
	if (retval) {
	cpus_clear(pr->performance->shared_cpu_map);
	cpu_set(i, pr->performance->shared_cpu_map);
	pr->performance->shared_type = CPUFREQ_SHARED_TYPE_ALL;
	}
	pr->performance = NULL; /* Will be set for real in register */
	}

	mutex_unlock(&performance_mutex);
	return retval;
	}
	EXPORT_SYMBOL(acpi_processor_preregister_performance);


	int
	acpi_processor_register_performance(struct acpi_processor_performance
	*performance, unsigned int cpu)
	{
	struct acpi_processor *pr;


	if (!(acpi_processor_ppc_status & PPC_REGISTERED))
	return -EINVAL;

	mutex_lock(&performance_mutex);

	pr = processors[cpu];
	if (!pr) {
	mutex_unlock(&performance_mutex);
	return -ENODEV;
	}

	if (pr->performance) {
	mutex_unlock(&performance_mutex);
	return -EBUSY;
	}

	WARN_ON(!performance);

	pr->performance = performance;

	if (acpi_processor_get_performance_info(pr)) {
	pr->performance = NULL;
	mutex_unlock(&performance_mutex);
	return -EIO;
	}

	acpi_cpufreq_add_file(pr);

	mutex_unlock(&performance_mutex);
	return 0;
	}

	EXPORT_SYMBOL(acpi_processor_register_performance);

	void
	acpi_processor_unregister_performance(struct acpi_processor_performance
	*performance, unsigned int cpu)
	{
	struct acpi_processor *pr;


	mutex_lock(&performance_mutex);

	pr = processors[cpu];
	if (!pr) {
	mutex_unlock(&performance_mutex);
	return;
	}

	if (pr->performance)
	kfree(pr->performance->states);
	pr->performance = NULL;

	acpi_cpufreq_remove_file(pr);

	mutex_unlock(&performance_mutex);

	return;
	}

	EXPORT_SYMBOL(acpi_processor_unregister_performance);