drivers/hwmon/pkgtemp.c

   1 /*
   2  * pkgtemp.c - Linux kernel module for processor package hardware monitoring
   3  *
   4  * Copyright (C) 2010 Fenghua Yu <fenghua.yu@intel.com>
   5  *
   6  * Inspired from many hwmon drivers especially coretemp.
   7  *
   8  * This program is free software; you can redistribute it and/or modify
   9  * it under the terms of the GNU General Public License as published by
  10  * the Free Software Foundation; version 2 of the License.
  11  *
  12  * This program is distributed in the hope that it will be useful,
  13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15  * GNU General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU General Public License
  18  * along with this program; if not, write to the Free Software
  19  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
  20  * 02110-1301 USA.
  21  */
  22
  23 #include <linux/module.h>
  24 #include <linux/init.h>
  25 #include <linux/slab.h>
  26 #include <linux/jiffies.h>
  27 #include <linux/hwmon.h>
  28 #include <linux/sysfs.h>
  29 #include <linux/hwmon-sysfs.h>
  30 #include <linux/err.h>
  31 #include <linux/mutex.h>
  32 #include <linux/list.h>
  33 #include <linux/platform_device.h>
  34 #include <linux/cpu.h>
  35 #include <asm/msr.h>
  36 #include <asm/processor.h>
  37
  38 #define DRVNAME "pkgtemp"
  39
  40 enum { SHOW_TEMP, SHOW_TJMAX, SHOW_TTARGET, SHOW_LABEL, SHOW_NAME };
  41
  42 /*
  43  * Functions declaration
  44  */
  45
  46 static struct pkgtemp_data *pkgtemp_update_device(struct device *dev);
  47
  48 struct pkgtemp_data {
  49         struct device *hwmon_dev;
  50         struct mutex update_lock;
  51         const char *name;
  52         u32 id;
  53         u16 phys_proc_id;
  54         char valid;             /* zero until following fields are valid */
  55         unsigned long last_updated;     /* in jiffies */
  56         int temp;
  57         int tjmax;
  58         int ttarget;
  59         u8 alarm;
  60 };
  61
  62 /*
  63  * Sysfs stuff
  64  */
  65
  66 static ssize_t show_name(struct device *dev, struct device_attribute
  67                           *devattr, char *buf)
  68 {
  69         int ret;
  70         struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
  71         struct pkgtemp_data *data = dev_get_drvdata(dev);
  72
  73         if (attr->index == SHOW_NAME)
  74                 ret = sprintf(buf, "%s\n", data->name);
  75         else    /* show label */
  76                 ret = sprintf(buf, "physical id %d\n",
  77                               data->phys_proc_id);
  78         return ret;
  79 }
  80
  81 static ssize_t show_alarm(struct device *dev, struct device_attribute
  82                           *devattr, char *buf)
  83 {
  84         struct pkgtemp_data *data = pkgtemp_update_device(dev);
  85         /* read the Out-of-spec log, never clear */
  86         return sprintf(buf, "%d\n", data->alarm);
  87 }
  88
  89 static ssize_t show_temp(struct device *dev,
  90                          struct device_attribute *devattr, char *buf)
  91 {
  92         struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
  93         struct pkgtemp_data *data = pkgtemp_update_device(dev);
  94         int err = 0;
  95
  96         if (attr->index == SHOW_TEMP)
  97                 err = data->valid ? sprintf(buf, "%d\n", data->temp) : -EAGAIN;
  98         else if (attr->index == SHOW_TJMAX)
  99                 err = sprintf(buf, "%d\n", data->tjmax);
 100         else
 101                 err = sprintf(buf, "%d\n", data->ttarget);
 102         return err;
 103 }
 104
 105 static SENSOR_DEVICE_ATTR(temp1_input, S_IRUGO, show_temp, NULL, SHOW_TEMP);
 106 static SENSOR_DEVICE_ATTR(temp1_crit, S_IRUGO, show_temp, NULL, SHOW_TJMAX);
 107 static SENSOR_DEVICE_ATTR(temp1_max, S_IRUGO, show_temp, NULL, SHOW_TTARGET);
 108 static DEVICE_ATTR(temp1_crit_alarm, S_IRUGO, show_alarm, NULL);
 109 static SENSOR_DEVICE_ATTR(temp1_label, S_IRUGO, show_name, NULL, SHOW_LABEL);
 110 static SENSOR_DEVICE_ATTR(name, S_IRUGO, show_name, NULL, SHOW_NAME);
 111
 112 static struct attribute *pkgtemp_attributes[] = {
 113         &sensor_dev_attr_name.dev_attr.attr,
 114         &sensor_dev_attr_temp1_label.dev_attr.attr,
 115         &dev_attr_temp1_crit_alarm.attr,
 116         &sensor_dev_attr_temp1_input.dev_attr.attr,
 117         &sensor_dev_attr_temp1_crit.dev_attr.attr,
 118         NULL
 119 };
 120
 121 static const struct attribute_group pkgtemp_group = {
 122         .attrs = pkgtemp_attributes,
 123 };
 124
 125 static struct pkgtemp_data *pkgtemp_update_device(struct device *dev)
 126 {
 127         struct pkgtemp_data *data = dev_get_drvdata(dev);
 128         unsigned int cpu;
 129         int err;
 130
 131         mutex_lock(&data->update_lock);
 132
 133         if (!data->valid || time_after(jiffies, data->last_updated + HZ)) {
 134                 u32 eax, edx;
 135
 136                 data->valid = 0;
 137                 cpu = data->id;
 138                 err = rdmsr_on_cpu(cpu, MSR_IA32_PACKAGE_THERM_STATUS,
 139                                    &eax, &edx);
 140                 if (!err) {
 141                         data->alarm = (eax >> 5) & 1;
 142                         data->temp = data->tjmax - (((eax >> 16)
 143                                                         & 0x7f) * 1000);
 144                         data->valid = 1;
 145                 } else
 146                         dev_dbg(dev, "Temperature data invalid (0x%x)\n", eax);
 147
 148                 data->last_updated = jiffies;
 149         }
 150
 151         mutex_unlock(&data->update_lock);
 152         return data;
 153 }
 154
 155 static int get_tjmax(int cpu, struct device *dev)
 156 {
 157         int default_tjmax = 100000;
 158         int err;
 159         u32 eax, edx;
 160         u32 val;
 161
 162         /* IA32_TEMPERATURE_TARGET contains the TjMax value */
 163         err = rdmsr_safe_on_cpu(cpu, MSR_IA32_TEMPERATURE_TARGET, &eax, &edx);
 164         if (!err) {
 165                 val = (eax >> 16) & 0xff;
 166                 if ((val > 80) && (val < 120)) {
 167                         dev_info(dev, "TjMax is %d C.\n", val);
 168                         return val * 1000;
 169                 }
 170         }
 171         dev_warn(dev, "Unable to read TjMax from CPU.\n");
 172         return default_tjmax;
 173 }
 174
 175 static int __devinit pkgtemp_probe(struct platform_device *pdev)
 176 {
 177         struct pkgtemp_data *data;
 178         int err;
 179         u32 eax, edx;
 180 #ifdef CONFIG_SMP
 181         struct cpuinfo_x86 *c = &cpu_data(pdev->id);
 182 #endif
 183
 184         data = kzalloc(sizeof(struct pkgtemp_data), GFP_KERNEL);
 185         if (!data) {
 186                 err = -ENOMEM;
 187                 dev_err(&pdev->dev, "Out of memory\n");
 188                 goto exit;
 189         }
 190
 191         data->id = pdev->id;
 192 #ifdef CONFIG_SMP
 193         data->phys_proc_id = c->phys_proc_id;
 194 #endif
 195         data->name = "pkgtemp";
 196         mutex_init(&data->update_lock);
 197
 198         /* test if we can access the THERM_STATUS MSR */
 199         err = rdmsr_safe_on_cpu(data->id, MSR_IA32_PACKAGE_THERM_STATUS,
 200                                 &eax, &edx);
 201         if (err) {
 202                 dev_err(&pdev->dev,
 203                         "Unable to access THERM_STATUS MSR, giving up\n");
 204                 goto exit_free;
 205         }
 206
 207         data->tjmax = get_tjmax(data->id, &pdev->dev);
 208         platform_set_drvdata(pdev, data);
 209
 210         err = rdmsr_safe_on_cpu(data->id, MSR_IA32_TEMPERATURE_TARGET,
 211                                 &eax, &edx);
 212         if (err) {
 213                 dev_warn(&pdev->dev, "Unable to read"
 214                                 " IA32_TEMPERATURE_TARGET MSR\n");
 215         } else {
 216                 data->ttarget = data->tjmax - (((eax >> 8) & 0xff) * 1000);
 217                 err = device_create_file(&pdev->dev,
 218                                 &sensor_dev_attr_temp1_max.dev_attr);
 219                 if (err)
 220                         goto exit_free;
 221         }
 222
 223         err = sysfs_create_group(&pdev->dev.kobj, &pkgtemp_group);
 224         if (err)
 225                 goto exit_dev;
 226
 227         data->hwmon_dev = hwmon_device_register(&pdev->dev);
 228         if (IS_ERR(data->hwmon_dev)) {
 229                 err = PTR_ERR(data->hwmon_dev);
 230                 dev_err(&pdev->dev, "Class registration failed (%d)\n",
 231                         err);
 232                 goto exit_class;
 233         }
 234
 235         return 0;
 236
 237 exit_class:
 238         sysfs_remove_group(&pdev->dev.kobj, &pkgtemp_group);
 239 exit_dev:
 240         device_remove_file(&pdev->dev, &sensor_dev_attr_temp1_max.dev_attr);
 241 exit_free:
 242         kfree(data);
 243 exit:
 244         return err;
 245 }
 246
 247 static int __devexit pkgtemp_remove(struct platform_device *pdev)
 248 {
 249         struct pkgtemp_data *data = platform_get_drvdata(pdev);
 250
 251         hwmon_device_unregister(data->hwmon_dev);
 252         sysfs_remove_group(&pdev->dev.kobj, &pkgtemp_group);
 253         device_remove_file(&pdev->dev, &sensor_dev_attr_temp1_max.dev_attr);
 254         platform_set_drvdata(pdev, NULL);
 255         kfree(data);
 256         return 0;
 257 }
 258
 259 static struct platform_driver pkgtemp_driver = {
 260         .driver = {
 261                 .owner = THIS_MODULE,
 262                 .name = DRVNAME,
 263         },
 264         .probe = pkgtemp_probe,
 265         .remove = __devexit_p(pkgtemp_remove),
 266 };
 267
 268 struct pdev_entry {
 269         struct list_head list;
 270         struct platform_device *pdev;
 271         unsigned int cpu;
 272 #ifdef CONFIG_SMP
 273         u16 phys_proc_id;
 274 #endif
 275 };
 276
 277 static LIST_HEAD(pdev_list);
 278 static DEFINE_MUTEX(pdev_list_mutex);
 279
 280 static int __cpuinit pkgtemp_device_add(unsigned int cpu)
 281 {
 282         int err;
 283         struct platform_device *pdev;
 284         struct pdev_entry *pdev_entry;
 285         struct cpuinfo_x86 *c = &cpu_data(cpu);
 286
 287         if (!cpu_has(c, X86_FEATURE_PTS))
 288                 return 0;
 289
 290         mutex_lock(&pdev_list_mutex);
 291
 292 #ifdef CONFIG_SMP
 293         /* Only keep the first entry in each package */
 294         list_for_each_entry(pdev_entry, &pdev_list, list) {
 295                 if (c->phys_proc_id == pdev_entry->phys_proc_id) {
 296                         err = 0;        /* Not an error */
 297                         goto exit;
 298                 }
 299         }
 300 #endif
 301
 302         pdev = platform_device_alloc(DRVNAME, cpu);
 303         if (!pdev) {
 304                 err = -ENOMEM;
 305                 printk(KERN_ERR DRVNAME ": Device allocation failed\n");
 306                 goto exit;
 307         }
 308
 309         pdev_entry = kzalloc(sizeof(struct pdev_entry), GFP_KERNEL);
 310         if (!pdev_entry) {
 311                 err = -ENOMEM;
 312                 goto exit_device_put;
 313         }
 314
 315         err = platform_device_add(pdev);
 316         if (err) {
 317                 printk(KERN_ERR DRVNAME ": Device addition failed (%d)\n",
 318                        err);
 319                 goto exit_device_free;
 320         }
 321
 322 #ifdef CONFIG_SMP
 323         pdev_entry->phys_proc_id = c->phys_proc_id;
 324 #endif
 325         pdev_entry->pdev = pdev;
 326         pdev_entry->cpu = cpu;
 327         list_add_tail(&pdev_entry->list, &pdev_list);
 328         mutex_unlock(&pdev_list_mutex);
 329
 330         return 0;
 331
 332 exit_device_free:
 333         kfree(pdev_entry);
 334 exit_device_put:
 335         platform_device_put(pdev);
 336 exit:
 337         mutex_unlock(&pdev_list_mutex);
 338         return err;
 339 }
 340
 341 #ifdef CONFIG_HOTPLUG_CPU
 342 static void __cpuinit pkgtemp_device_remove(unsigned int cpu)
 343 {
 344         struct pdev_entry *p;
 345         unsigned int i;
 346         int err;
 347
 348         mutex_lock(&pdev_list_mutex);
 349         list_for_each_entry(p, &pdev_list, list) {
 350                 if (p->cpu != cpu)
 351                         continue;
 352
 353                 platform_device_unregister(p->pdev);
 354                 list_del(&p->list);
 355                 mutex_unlock(&pdev_list_mutex);
 356                 kfree(p);
 357                 for_each_cpu(i, cpu_core_mask(cpu)) {
 358                         if (i != cpu) {
 359                                 err = pkgtemp_device_add(i);
 360                                 if (!err)
 361                                         break;
 362                         }
 363                 }
 364                 return;
 365         }
 366         mutex_unlock(&pdev_list_mutex);
 367 }
 368
 369 static int __cpuinit pkgtemp_cpu_callback(struct notifier_block *nfb,
 370                                  unsigned long action, void *hcpu)
 371 {
 372         unsigned int cpu = (unsigned long) hcpu;
 373
 374         switch (action) {
 375         case CPU_ONLINE:
 376         case CPU_DOWN_FAILED:
 377                 pkgtemp_device_add(cpu);
 378                 break;
 379         case CPU_DOWN_PREPARE:
 380                 pkgtemp_device_remove(cpu);
 381                 break;
 382         }
 383         return NOTIFY_OK;
 384 }
 385
 386 static struct notifier_block pkgtemp_cpu_notifier __refdata = {
 387         .notifier_call = pkgtemp_cpu_callback,
 388 };
 389 #endif                          /* !CONFIG_HOTPLUG_CPU */
 390
 391 static int __init pkgtemp_init(void)
 392 {
 393         int i, err = -ENODEV;
 394         struct pdev_entry *p, *n;
 395
 396         /* quick check if we run Intel */
 397         if (cpu_data(0).x86_vendor != X86_VENDOR_INTEL)
 398                 goto exit;
 399
 400         err = platform_driver_register(&pkgtemp_driver);
 401         if (err)
 402                 goto exit;
 403
 404         for_each_online_cpu(i) {
 405                 err = pkgtemp_device_add(i);
 406                 if (err)
 407                         goto exit_devices_unreg;
 408         }
 409         if (list_empty(&pdev_list)) {
 410                 err = -ENODEV;
 411                 goto exit_driver_unreg;
 412         }
 413
 414 #ifdef CONFIG_HOTPLUG_CPU
 415         register_hotcpu_notifier(&pkgtemp_cpu_notifier);
 416 #endif
 417         return 0;
 418
 419 exit_devices_unreg:
 420         mutex_lock(&pdev_list_mutex);
 421         list_for_each_entry_safe(p, n, &pdev_list, list) {
 422                 platform_device_unregister(p->pdev);
 423                 list_del(&p->list);
 424                 kfree(p);
 425         }
 426         mutex_unlock(&pdev_list_mutex);
 427 exit_driver_unreg:
 428         platform_driver_unregister(&pkgtemp_driver);
 429 exit:
 430         return err;
 431 }
 432
 433 static void __exit pkgtemp_exit(void)
 434 {
 435         struct pdev_entry *p, *n;
 436 #ifdef CONFIG_HOTPLUG_CPU
 437         unregister_hotcpu_notifier(&pkgtemp_cpu_notifier);
 438 #endif
 439         mutex_lock(&pdev_list_mutex);
 440         list_for_each_entry_safe(p, n, &pdev_list, list) {
 441                 platform_device_unregister(p->pdev);
 442                 list_del(&p->list);
 443                 kfree(p);
 444         }
 445         mutex_unlock(&pdev_list_mutex);
 446         platform_driver_unregister(&pkgtemp_driver);
 447 }
 448
 449 MODULE_AUTHOR("Fenghua Yu <fenghua.yu@intel.com>");
 450 MODULE_DESCRIPTION("Intel processor package temperature monitor");
 451 MODULE_LICENSE("GPL");
 452
 453 module_init(pkgtemp_init)
 454 module_exit(pkgtemp_exit)