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