/*
   * driver/base/topology.c - Populate sysfs with cpu topology information
   *
   * Written by: Zhang Yanmin, Intel Corporation
   *
   * Copyright (C) 2006, Intel Corp.
   *
   * All rights reserved.
   *
   * 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, GOOD TITLE or
   * NON INFRINGEMENT.  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., 675 Mass Ave, Cambridge, MA 02139, USA.
   *
   */

  #include <linux/init.h>
  #include <linux/mm.h>
  #include <linux/cpu.h>
  #include <linux/module.h>

  #include <linux/hardirq.h>

  #include <linux/topology.h>

  #define define_one_ro_named(_name, _func)				\

  	static DEVICE_ATTR(_name, 0444, _func, NULL)

  
  #define define_one_ro(_name)				\

  	static DEVICE_ATTR(_name, 0444, show_##_name, NULL)

  
  #define define_id_show_func(name)				\

  static ssize_t show_##name(struct device *dev,			\
  		struct device_attribute *attr, char *buf)	\

  {								\
  	unsigned int cpu = dev->id;				\
  	return sprintf(buf, "%d
  ", topology_##name(cpu));	\
  }

  #if defined(topology_thread_cpumask) || defined(topology_core_cpumask) || \
      defined(topology_book_cpumask)

  static ssize_t show_cpumap(int type, const struct cpumask *mask, char *buf)

  {
  	ptrdiff_t len = PTR_ALIGN(buf + PAGE_SIZE - 1, PAGE_SIZE) - buf;
  	int n = 0;
  
  	if (len > 1) {
  		n = type?

  			cpulist_scnprintf(buf, len-2, mask) :
  			cpumask_scnprintf(buf, len-2, mask);

  		buf[n++] = '
  ';
  		buf[n] = '\0';
  	}
  	return n;
  }

  #endif

  #ifdef arch_provides_topology_pointers

  #define define_siblings_show_map(name)					\

  static ssize_t show_##name(struct device *dev,				\
  			   struct device_attribute *attr, char *buf)	\

  {									\
  	unsigned int cpu = dev->id;					\

  	return show_cpumap(0, topology_##name(cpu), buf);		\

  }
  
  #define define_siblings_show_list(name)					\

  static ssize_t show_##name##_list(struct device *dev,			\
  				  struct device_attribute *attr,	\

  				  char *buf)				\

  {									\

  	unsigned int cpu = dev->id;					\

  	return show_cpumap(1, topology_##name(cpu), buf);		\

  }

  #else
  #define define_siblings_show_map(name)					\

  static ssize_t show_##name(struct device *dev,				\
  			   struct device_attribute *attr, char *buf)	\

  {									\

  	return show_cpumap(0, topology_##name(dev->id), buf);		\

  }
  
  #define define_siblings_show_list(name)					\

  static ssize_t show_##name##_list(struct device *dev,			\
  				  struct device_attribute *attr,	\

  				  char *buf)				\

  {									\

  	return show_cpumap(1, topology_##name(dev->id), buf);		\

  }
  #endif

  #define define_siblings_show_func(name)		\
  	define_siblings_show_map(name); define_siblings_show_list(name)

  define_id_show_func(physical_package_id);
  define_one_ro(physical_package_id);

  define_id_show_func(core_id);
  define_one_ro(core_id);

  define_siblings_show_func(thread_cpumask);
  define_one_ro_named(thread_siblings, show_thread_cpumask);
  define_one_ro_named(thread_siblings_list, show_thread_cpumask_list);

  define_siblings_show_func(core_cpumask);
  define_one_ro_named(core_siblings, show_core_cpumask);
  define_one_ro_named(core_siblings_list, show_core_cpumask_list);

  #ifdef CONFIG_SCHED_BOOK
  define_id_show_func(book_id);
  define_one_ro(book_id);
  define_siblings_show_func(book_cpumask);
  define_one_ro_named(book_siblings, show_book_cpumask);
  define_one_ro_named(book_siblings_list, show_book_cpumask_list);
  #endif

  static struct attribute *default_attrs[] = {

  	&dev_attr_physical_package_id.attr,
  	&dev_attr_core_id.attr,
  	&dev_attr_thread_siblings.attr,
  	&dev_attr_thread_siblings_list.attr,
  	&dev_attr_core_siblings.attr,
  	&dev_attr_core_siblings_list.attr,

  #ifdef CONFIG_SCHED_BOOK

  	&dev_attr_book_id.attr,
  	&dev_attr_book_siblings.attr,
  	&dev_attr_book_siblings_list.attr,

  #endif

  	NULL
  };
  
  static struct attribute_group topology_attr_group = {
  	.attrs = default_attrs,
  	.name = "topology"
  };
  
  /* Add/Remove cpu_topology interface for CPU device */

  static int __cpuinit topology_add_dev(unsigned int cpu)

  {

  	struct device *dev = get_cpu_device(cpu);

  	return sysfs_create_group(&dev->kobj, &topology_attr_group);

  }

  static void __cpuinit topology_remove_dev(unsigned int cpu)

  {

  	struct device *dev = get_cpu_device(cpu);

  	sysfs_remove_group(&dev->kobj, &topology_attr_group);

  }

  static int __cpuinit topology_cpu_callback(struct notifier_block *nfb,

  					   unsigned long action, void *hcpu)

  {
  	unsigned int cpu = (unsigned long)hcpu;

  	int rc = 0;

  	switch (action) {

  	case CPU_UP_PREPARE:

  	case CPU_UP_PREPARE_FROZEN:

  		rc = topology_add_dev(cpu);

  		break;

  	case CPU_UP_CANCELED:

  	case CPU_UP_CANCELED_FROZEN:

  	case CPU_DEAD:

  	case CPU_DEAD_FROZEN:

  		topology_remove_dev(cpu);

  		break;
  	}

  	return notifier_from_errno(rc);

  }

  
  static int __cpuinit topology_sysfs_init(void)
  {

  	int cpu;
  	int rc;

  	for_each_online_cpu(cpu) {
  		rc = topology_add_dev(cpu);
  		if (rc)
  			return rc;

  	}

  	hotcpu_notifier(topology_cpu_callback, 0);

  
  	return 0;
  }
  
  device_initcall(topology_sysfs_init);