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