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 #include <asm/smp.h>
  38
  39 #define DRVNAME "pkgtemp"
  40
  41 enum { SHOW_TEMP, SHOW_TJMAX, SHOW_TTARGET, SHOW_LABEL, SHOW_NAME };
  42
  43 /*
  44  * Functions declaration
  45  */
  46
  47 static struct pkgtemp_data *pkgtemp_update_device(struct device *dev);
  48
  49 struct pkgtemp_data {
  50         struct device *hwmon_dev;
  51         struct mutex update_lock;
  52         const char *name;
  53         u32 id;
  54         u16 phys_proc_id;
  55         char valid;             /* zero until following fields are valid */
  56         unsigned long last_updated;     /* in jiffies */
  57         int temp;
  58         int tjmax;
  59         int ttarget;
  60         u8 alarm;
  61 };
  62
  63 /*
  64  * Sysfs stuff
  65  */
  66
  67 static ssize_t show_name(struct device *dev, struct device_attribute
  68                           *devattr, char *buf)
  69 {
  70         int ret;
  71         struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
  72         struct pkgtemp_data *data = dev_get_drvdata(dev);
  73
  74         if (attr->index == SHOW_NAME)
  75                 ret = sprintf(buf, "%s\n", data->name);
  76         else    /* show label */
  77                 ret = sprintf(buf, "physical id %d\n",
  78                               data->phys_proc_id);
  79         return ret;
  80 }
  81
  82 static ssize_t show_alarm(struct device *dev, struct device_attribute
  83                           *devattr, char *buf)
  84 {
  85         struct pkgtemp_data *data = pkgtemp_update_device(dev);
  86         /* read the Out-of-spec log, never clear */
  87         return sprintf(buf, "%d\n", data->alarm);
  88 }
  89
  90 static ssize_t show_temp(struct device *dev,
  91                          struct device_attribute *devattr, char *buf)
  92 {
  93         struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
  94         struct pkgtemp_data *data = pkgtemp_update_device(dev);
  95         int err = 0;
  96
  97         if (attr->index == SHOW_TEMP)
  98                 err = data->valid ? sprintf(buf, "%d\n", data->temp) : -EAGAIN;
  99         else if (attr->index == SHOW_TJMAX)
 100                 err = sprintf(buf, "%d\n", data->tjmax);
 101         else
 102                 err = sprintf(buf, "%d\n", data->ttarget);
 103         return err;
 104 }
 105
 106 static SENSOR_DEVICE_ATTR(temp1_input, S_IRUGO, show_temp, NULL, SHOW_TEMP);
 107 static SENSOR_DEVICE_ATTR(temp1_crit, S_IRUGO, show_temp, NULL, SHOW_TJMAX);
 108 static SENSOR_DEVICE_ATTR(temp1_max, S_IRUGO, show_temp, NULL, SHOW_TTARGET);
 109 static DEVICE_ATTR(temp1_crit_alarm, S_IRUGO, show_alarm, NULL);
 110 static SENSOR_DEVICE_ATTR(temp1_label, S_IRUGO, show_name, NULL, SHOW_LABEL);
 111 static SENSOR_DEVICE_ATTR(name, S_IRUGO, show_name, NULL, SHOW_NAME);
 112
 113 static struct attribute *pkgtemp_attributes[] = {
 114         &sensor_dev_attr_name.dev_attr.attr,
 115         &sensor_dev_attr_temp1_label.dev_attr.attr,
 116         &dev_attr_temp1_crit_alarm.attr,
 117         &sensor_dev_attr_temp1_input.dev_attr.attr,
 118         &sensor_dev_attr_temp1_crit.dev_attr.attr,
 119         NULL
 120 };
 121
 122 static const struct attribute_group pkgtemp_group = {
 123         .attrs = pkgtemp_attributes,
 124 };
 125
 126 static struct pkgtemp_data *pkgtemp_update_device(struct device *dev)
 127 {
 128         struct pkgtemp_data *data = dev_get_drvdata(dev);
 129         unsigned int cpu;
 130         int err;
 131
 132         mutex_lock(&data->update_lock);
 133
 134         if (!data->valid || time_after(jiffies, data->last_updated + HZ)) {
 135                 u32 eax, edx;
 136
 137                 data->valid = 0;
 138                 cpu = data->id;
 139                 err = rdmsr_on_cpu(cpu, MSR_IA32_PACKAGE_THERM_STATUS,
 140                                    &eax, &edx);
 141                 if (!err) {
 142                         data->alarm = (eax >> 5) & 1;
 143                         data->temp = data->tjmax - (((eax >> 16)
 144                                                         & 0x7f) * 1000);
 145                         data->valid = 1;
 146                 } else
 147                         dev_dbg(dev, "Temperature data invalid (0x%x)\n", eax);
 148
 149                 data->last_updated = jiffies;
 150         }
 151
 152         mutex_unlock(&data->update_lock);
 153         return data;
 154 }
 155
 156 static int get_tjmax(int cpu, struct device *dev)
 157 {
 158         int default_tjmax = 100000;
 159         int err;
 160         u32 eax, edx;
 161         u32 val;
 162
 163         /* IA32_TEMPERATURE_TARGET contains the TjMax value */
 164         err = rdmsr_safe_on_cpu(cpu, MSR_IA32_TEMPERATURE_TARGET, &eax, &edx);
 165         if (!err) {
 166                 val = (eax >> 16) & 0xff;
 167                 if ((val > 80) && (val < 120)) {
 168                         dev_info(dev, "TjMax is %d C.\n", val);
 169                         return val * 1000;
 170                 }
 171         }
 172         dev_warn(dev, "Unable to read TjMax from CPU.\n");
 173         return default_tjmax;
 174 }
 175
 176 static int __devinit pkgtemp_probe(struct platform_device *pdev)
 177 {
 178         struct pkgtemp_data *data;
 179         int err;
 180         u32 eax, edx;
 181 #ifdef CONFIG_SMP
 182         struct cpuinfo_x86 *c = &cpu_data(pdev->id);
 183 #endif
 184
 185         data = kzalloc(sizeof(struct pkgtemp_data), GFP_KERNEL);
 186         if (!data) {
 187                 err = -ENOMEM;
 188                 dev_err(&pdev->dev, "Out of memory\n");
 189                 goto exit;
 190         }
 191
 192         data->id = pdev->id;
 193 #ifdef CONFIG_SMP
 194         data->phys_proc_id = c->phys_proc_id;
 195 #endif
 196         data->name = "pkgtemp";
 197         mutex_init(&data->update_lock);
 198
 199         /* test if we can access the THERM_STATUS MSR */
 200         err = rdmsr_safe_on_cpu(data->id, MSR_IA32_PACKAGE_THERM_STATUS,
 201                                 &eax, &edx);
 202         if (err) {
 203                 dev_err(&pdev->dev,
 204                         "Unable to access THERM_STATUS MSR, giving up\n");
 205                 goto exit_free;
 206         }
 207
 208         data->tjmax = get_tjmax(data->id, &pdev->dev);
 209         platform_set_drvdata(pdev, data);
 210
 211         err = rdmsr_safe_on_cpu(data->id, MSR_IA32_TEMPERATURE_TARGET,
 212                                 &eax, &edx);
 213         if (err) {
 214                 dev_warn(&pdev->dev, "Unable to read"
 215                                 " IA32_TEMPERATURE_TARGET MSR\n");
 216         } else {
 217                 data->ttarget = data->tjmax - (((eax >> 8) & 0xff) * 1000);
 218                 err = device_create_file(&pdev->dev,
 219                                 &sensor_dev_attr_temp1_max.dev_attr);
 220                 if (err)
 221                         goto exit_free;
 222         }
 223
 224         err = sysfs_create_group(&pdev->dev.kobj, &pkgtemp_group);
 225         if (err)
 226                 goto exit_dev;
 227
 228         data->hwmon_dev = hwmon_device_register(&pdev->dev);
 229         if (IS_ERR(data->hwmon_dev)) {
 230                 err = PTR_ERR(data->hwmon_dev);
 231                 dev_err(&pdev->dev, "Class registration failed (%d)\n",
 232                         err);
 233                 goto exit_class;
 234         }
 235
 236         return 0;
 237
 238 exit_class:
 239         sysfs_remove_group(&pdev->dev.kobj, &pkgtemp_group);
 240 exit_dev:
 241         device_remove_file(&pdev->dev, &sensor_dev_attr_temp1_max.dev_attr);
 242 exit_free:
 243         kfree(data);
 244 exit:
 245         return err;
 246 }
 247
 248 static int __devexit pkgtemp_remove(struct platform_device *pdev)
 249 {
 250         struct pkgtemp_data *data = platform_get_drvdata(pdev);
 251
 252         hwmon_device_unregister(data->hwmon_dev);
 253         sysfs_remove_group(&pdev->dev.kobj, &pkgtemp_group);
 254         device_remove_file(&pdev->dev, &sensor_dev_attr_temp1_max.dev_attr);
 255         platform_set_drvdata(pdev, NULL);
 256         kfree(data);
 257         return 0;
 258 }
 259
 260 static struct platform_driver pkgtemp_driver = {
 261         .driver = {
 262                 .owner = THIS_MODULE,
 263                 .name = DRVNAME,
 264         },
 265         .probe = pkgtemp_probe,
 266         .remove = __devexit_p(pkgtemp_remove),
 267 };
 268
 269 struct pdev_entry {
 270         struct list_head list;
 271         struct platform_device *pdev;
 272         unsigned int cpu;
 273 #ifdef CONFIG_SMP
 274         u16 phys_proc_id;
 275 #endif
 276 };
 277
 278 static LIST_HEAD(pdev_list);
 279 static DEFINE_MUTEX(pdev_list_mutex);
 280
 281 static int __cpuinit pkgtemp_device_add(unsigned int cpu)
 282 {
 283         int err;
 284         struct platform_device *pdev;
 285         struct pdev_entry *pdev_entry;
 286         struct cpuinfo_x86 *c = &cpu_data(cpu);
 287
 288         if (!cpu_has(c, X86_FEATURE_PTS))
 289                 return 0;
 290
 291         mutex_lock(&pdev_list_mutex);
 292
 293 #ifdef CONFIG_SMP
 294         /* Only keep the first entry in each package */
 295         list_for_each_entry(pdev_entry, &pdev_list, list) {
 296                 if (c->phys_proc_id == pdev_entry->phys_proc_id) {
 297                         err = 0;        /* Not an error */
 298                         goto exit;
 299                 }
 300         }
 301 #endif
 302
 303         pdev = platform_device_alloc(DRVNAME, cpu);
 304         if (!pdev) {
 305                 err = -ENOMEM;
 306                 printk(KERN_ERR DRVNAME ": Device allocation failed\n");
 307                 goto exit;
 308         }
 309
 310         pdev_entry = kzalloc(sizeof(struct pdev_entry), GFP_KERNEL);
 311         if (!pdev_entry) {
 312                 err = -ENOMEM;
 313                 goto exit_device_put;
 314         }
 315
 316         err = platform_device_add(pdev);
 317         if (err) {
 318                 printk(KERN_ERR DRVNAME ": Device addition failed (%d)\n",
 319                        err);
 320                 goto exit_device_free;
 321         }
 322
 323 #ifdef CONFIG_SMP
 324         pdev_entry->phys_proc_id = c->phys_proc_id;
 325 #endif
 326         pdev_entry->pdev = pdev;
 327         pdev_entry->cpu = cpu;
 328         list_add_tail(&pdev_entry->list, &pdev_list);
 329         mutex_unlock(&pdev_list_mutex);
 330
 331         return 0;
 332
 333 exit_device_free:
 334         kfree(pdev_entry);
 335 exit_device_put:
 336         platform_device_put(pdev);
 337 exit:
 338         mutex_unlock(&pdev_list_mutex);
 339         return err;
 340 }
 341
 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
 390 static int __init pkgtemp_init(void)
 391 {
 392         int i, err = -ENODEV;
 393
 394         /* quick check if we run Intel */
 395         if (cpu_data(0).x86_vendor != X86_VENDOR_INTEL)
 396                 goto exit;
 397
 398         err = platform_driver_register(&pkgtemp_driver);
 399         if (err)
 400                 goto exit;
 401
 402         for_each_online_cpu(i)
 403                 pkgtemp_device_add(i);
 404
 405 #ifndef CONFIG_HOTPLUG_CPU
 406         if (list_empty(&pdev_list)) {
 407                 err = -ENODEV;
 408                 goto exit_driver_unreg;
 409         }
 410 #endif
 411
 412         register_hotcpu_notifier(&pkgtemp_cpu_notifier);
 413         return 0;
 414
 415 #ifndef CONFIG_HOTPLUG_CPU
 416 exit_driver_unreg:
 417         platform_driver_unregister(&pkgtemp_driver);
 418 #endif
 419 exit:
 420         return err;
 421 }
 422
 423 static void __exit pkgtemp_exit(void)
 424 {
 425         struct pdev_entry *p, *n;
 426
 427         unregister_hotcpu_notifier(&pkgtemp_cpu_notifier);
 428         mutex_lock(&pdev_list_mutex);
 429         list_for_each_entry_safe(p, n, &pdev_list, list) {
 430                 platform_device_unregister(p->pdev);
 431                 list_del(&p->list);
 432                 kfree(p);
 433         }
 434         mutex_unlock(&pdev_list_mutex);
 435         platform_driver_unregister(&pkgtemp_driver);
 436 }
 437
 438 MODULE_AUTHOR("Fenghua Yu <fenghua.yu@intel.com>");
 439 MODULE_DESCRIPTION("Intel processor package temperature monitor");
 440 MODULE_LICENSE("GPL");
 441
 442 module_init(pkgtemp_init)
 443 module_exit(pkgtemp_exit)