Rudolf Marek | bebe467 | 2007-05-08 17:22:02 +0200 | [diff] [blame] | 1 | /* |
| 2 | * coretemp.c - Linux kernel module for hardware monitoring |
| 3 | * |
| 4 | * Copyright (C) 2007 Rudolf Marek <r.marek@assembler.cz> |
| 5 | * |
| 6 | * Inspired from many hwmon drivers |
| 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 <asm/msr.h> |
| 37 | #include <asm/processor.h> |
| 38 | |
| 39 | #define DRVNAME "coretemp" |
| 40 | |
| 41 | typedef enum { SHOW_TEMP, SHOW_TJMAX, SHOW_LABEL, SHOW_NAME } SHOW; |
| 42 | |
| 43 | /* |
| 44 | * Functions declaration |
| 45 | */ |
| 46 | |
| 47 | static struct coretemp_data *coretemp_update_device(struct device *dev); |
| 48 | |
| 49 | struct coretemp_data { |
| 50 | struct class_device *class_dev; |
| 51 | struct mutex update_lock; |
| 52 | const char *name; |
| 53 | u32 id; |
| 54 | char valid; /* zero until following fields are valid */ |
| 55 | unsigned long last_updated; /* in jiffies */ |
| 56 | int temp; |
| 57 | int tjmax; |
| 58 | u8 alarm; |
| 59 | }; |
| 60 | |
| 61 | static struct coretemp_data *coretemp_update_device(struct device *dev); |
| 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 coretemp_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, "Core %d\n", data->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 coretemp_data *data = coretemp_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 coretemp_data *data = coretemp_update_device(dev); |
| 94 | int err; |
| 95 | |
| 96 | if (attr->index == SHOW_TEMP) |
| 97 | err = data->valid ? sprintf(buf, "%d\n", data->temp) : -EAGAIN; |
| 98 | else |
| 99 | err = sprintf(buf, "%d\n", data->tjmax); |
| 100 | |
| 101 | return err; |
| 102 | } |
| 103 | |
| 104 | static SENSOR_DEVICE_ATTR(temp1_input, S_IRUGO, show_temp, NULL, |
| 105 | SHOW_TEMP); |
| 106 | static SENSOR_DEVICE_ATTR(temp1_crit, S_IRUGO, show_temp, NULL, |
| 107 | SHOW_TJMAX); |
| 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 *coretemp_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 coretemp_group = { |
| 122 | .attrs = coretemp_attributes, |
| 123 | }; |
| 124 | |
| 125 | static struct coretemp_data *coretemp_update_device(struct device *dev) |
| 126 | { |
| 127 | struct coretemp_data *data = dev_get_drvdata(dev); |
| 128 | |
| 129 | mutex_lock(&data->update_lock); |
| 130 | |
| 131 | if (!data->valid || time_after(jiffies, data->last_updated + HZ)) { |
| 132 | u32 eax, edx; |
| 133 | |
| 134 | data->valid = 0; |
| 135 | rdmsr_on_cpu(data->id, MSR_IA32_THERM_STATUS, &eax, &edx); |
| 136 | data->alarm = (eax >> 5) & 1; |
| 137 | /* update only if data has been valid */ |
| 138 | if (eax & 0x80000000) { |
| 139 | data->temp = data->tjmax - (((eax >> 16) |
| 140 | & 0x7f) * 1000); |
| 141 | data->valid = 1; |
| 142 | } else { |
| 143 | dev_dbg(dev, "Temperature data invalid (0x%x)\n", eax); |
| 144 | } |
| 145 | data->last_updated = jiffies; |
| 146 | } |
| 147 | |
| 148 | mutex_unlock(&data->update_lock); |
| 149 | return data; |
| 150 | } |
| 151 | |
| 152 | static int __devinit coretemp_probe(struct platform_device *pdev) |
| 153 | { |
| 154 | struct coretemp_data *data; |
| 155 | struct cpuinfo_x86 *c = &(cpu_data)[pdev->id]; |
| 156 | int err; |
| 157 | u32 eax, edx; |
| 158 | |
| 159 | if (!(data = kzalloc(sizeof(struct coretemp_data), GFP_KERNEL))) { |
| 160 | err = -ENOMEM; |
| 161 | dev_err(&pdev->dev, "Out of memory\n"); |
| 162 | goto exit; |
| 163 | } |
| 164 | |
| 165 | data->id = pdev->id; |
| 166 | data->name = "coretemp"; |
| 167 | mutex_init(&data->update_lock); |
| 168 | /* Tjmax default is 100 degrees C */ |
| 169 | data->tjmax = 100000; |
| 170 | |
| 171 | /* test if we can access the THERM_STATUS MSR */ |
| 172 | err = rdmsr_safe_on_cpu(data->id, MSR_IA32_THERM_STATUS, &eax, &edx); |
| 173 | if (err) { |
| 174 | dev_err(&pdev->dev, |
| 175 | "Unable to access THERM_STATUS MSR, giving up\n"); |
| 176 | goto exit_free; |
| 177 | } |
| 178 | |
Rudolf Marek | 67f363b | 2007-05-27 22:17:43 +0200 | [diff] [blame] | 179 | /* Check if we have problem with errata AE18 of Core processors: |
| 180 | Readings might stop update when processor visited too deep sleep, |
| 181 | fixed for stepping D0 (6EC). |
| 182 | */ |
| 183 | |
| 184 | if ((c->x86_model == 0xe) && (c->x86_mask < 0xc)) { |
| 185 | /* check for microcode update */ |
| 186 | rdmsr_on_cpu(data->id, MSR_IA32_UCODE_REV, &eax, &edx); |
| 187 | if (edx < 0x39) { |
Jean Delvare | 6d79af7 | 2007-06-23 17:16:24 -0700 | [diff] [blame^] | 188 | err = -ENODEV; |
Rudolf Marek | 67f363b | 2007-05-27 22:17:43 +0200 | [diff] [blame] | 189 | dev_err(&pdev->dev, |
| 190 | "Errata AE18 not fixed, update BIOS or " |
| 191 | "microcode of the CPU!\n"); |
| 192 | goto exit_free; |
| 193 | } |
| 194 | } |
| 195 | |
Rudolf Marek | bebe467 | 2007-05-08 17:22:02 +0200 | [diff] [blame] | 196 | /* Some processors have Tjmax 85 following magic should detect it |
| 197 | Intel won't disclose the information without signed NDA, but |
| 198 | individuals cannot sign it. Catch(ed) 22. |
| 199 | */ |
| 200 | |
| 201 | if (((c->x86_model == 0xf) && (c->x86_mask > 3)) || |
| 202 | (c->x86_model == 0xe)) { |
| 203 | err = rdmsr_safe_on_cpu(data->id, 0xee, &eax, &edx); |
| 204 | if (err) { |
| 205 | dev_warn(&pdev->dev, |
| 206 | "Unable to access MSR 0xEE, Tjmax left at %d " |
| 207 | "degrees C\n", data->tjmax/1000); |
| 208 | } else if (eax & 0x40000000) { |
| 209 | data->tjmax = 85000; |
| 210 | } |
| 211 | } |
| 212 | |
Rudolf Marek | 67f363b | 2007-05-27 22:17:43 +0200 | [diff] [blame] | 213 | /* Intel says that above should not work for desktop Core2 processors, |
| 214 | but it seems to work. There is no other way how get the absolute |
| 215 | readings. Warn the user about this. First check if are desktop, |
| 216 | bit 50 of MSR_IA32_PLATFORM_ID should be 0. |
| 217 | */ |
| 218 | |
| 219 | rdmsr_safe_on_cpu(data->id, MSR_IA32_PLATFORM_ID, &eax, &edx); |
| 220 | |
| 221 | if ((c->x86_model == 0xf) && (!(edx & 0x00040000))) { |
| 222 | dev_warn(&pdev->dev, "Using undocumented features, absolute " |
| 223 | "temperature might be wrong!\n"); |
| 224 | } |
| 225 | |
Rudolf Marek | bebe467 | 2007-05-08 17:22:02 +0200 | [diff] [blame] | 226 | platform_set_drvdata(pdev, data); |
| 227 | |
| 228 | if ((err = sysfs_create_group(&pdev->dev.kobj, &coretemp_group))) |
| 229 | goto exit_free; |
| 230 | |
| 231 | data->class_dev = hwmon_device_register(&pdev->dev); |
| 232 | if (IS_ERR(data->class_dev)) { |
| 233 | err = PTR_ERR(data->class_dev); |
| 234 | dev_err(&pdev->dev, "Class registration failed (%d)\n", |
| 235 | err); |
| 236 | goto exit_class; |
| 237 | } |
| 238 | |
| 239 | return 0; |
| 240 | |
| 241 | exit_class: |
| 242 | sysfs_remove_group(&pdev->dev.kobj, &coretemp_group); |
| 243 | exit_free: |
| 244 | kfree(data); |
| 245 | exit: |
| 246 | return err; |
| 247 | } |
| 248 | |
| 249 | static int __devexit coretemp_remove(struct platform_device *pdev) |
| 250 | { |
| 251 | struct coretemp_data *data = platform_get_drvdata(pdev); |
| 252 | |
| 253 | hwmon_device_unregister(data->class_dev); |
| 254 | sysfs_remove_group(&pdev->dev.kobj, &coretemp_group); |
| 255 | platform_set_drvdata(pdev, NULL); |
| 256 | kfree(data); |
| 257 | return 0; |
| 258 | } |
| 259 | |
| 260 | static struct platform_driver coretemp_driver = { |
| 261 | .driver = { |
| 262 | .owner = THIS_MODULE, |
| 263 | .name = DRVNAME, |
| 264 | }, |
| 265 | .probe = coretemp_probe, |
| 266 | .remove = __devexit_p(coretemp_remove), |
| 267 | }; |
| 268 | |
| 269 | struct pdev_entry { |
| 270 | struct list_head list; |
| 271 | struct platform_device *pdev; |
| 272 | unsigned int cpu; |
| 273 | }; |
| 274 | |
| 275 | static LIST_HEAD(pdev_list); |
| 276 | static DEFINE_MUTEX(pdev_list_mutex); |
| 277 | |
| 278 | static int __cpuinit coretemp_device_add(unsigned int cpu) |
| 279 | { |
| 280 | int err; |
| 281 | struct platform_device *pdev; |
| 282 | struct pdev_entry *pdev_entry; |
| 283 | |
| 284 | pdev = platform_device_alloc(DRVNAME, cpu); |
| 285 | if (!pdev) { |
| 286 | err = -ENOMEM; |
| 287 | printk(KERN_ERR DRVNAME ": Device allocation failed\n"); |
| 288 | goto exit; |
| 289 | } |
| 290 | |
| 291 | pdev_entry = kzalloc(sizeof(struct pdev_entry), GFP_KERNEL); |
| 292 | if (!pdev_entry) { |
| 293 | err = -ENOMEM; |
| 294 | goto exit_device_put; |
| 295 | } |
| 296 | |
| 297 | err = platform_device_add(pdev); |
| 298 | if (err) { |
| 299 | printk(KERN_ERR DRVNAME ": Device addition failed (%d)\n", |
| 300 | err); |
| 301 | goto exit_device_free; |
| 302 | } |
| 303 | |
| 304 | pdev_entry->pdev = pdev; |
| 305 | pdev_entry->cpu = cpu; |
| 306 | mutex_lock(&pdev_list_mutex); |
| 307 | list_add_tail(&pdev_entry->list, &pdev_list); |
| 308 | mutex_unlock(&pdev_list_mutex); |
| 309 | |
| 310 | return 0; |
| 311 | |
| 312 | exit_device_free: |
| 313 | kfree(pdev_entry); |
| 314 | exit_device_put: |
| 315 | platform_device_put(pdev); |
| 316 | exit: |
| 317 | return err; |
| 318 | } |
| 319 | |
| 320 | #ifdef CONFIG_HOTPLUG_CPU |
| 321 | void coretemp_device_remove(unsigned int cpu) |
| 322 | { |
| 323 | struct pdev_entry *p, *n; |
| 324 | mutex_lock(&pdev_list_mutex); |
| 325 | list_for_each_entry_safe(p, n, &pdev_list, list) { |
| 326 | if (p->cpu == cpu) { |
| 327 | platform_device_unregister(p->pdev); |
| 328 | list_del(&p->list); |
| 329 | kfree(p); |
| 330 | } |
| 331 | } |
| 332 | mutex_unlock(&pdev_list_mutex); |
| 333 | } |
| 334 | |
| 335 | static int coretemp_cpu_callback(struct notifier_block *nfb, |
| 336 | unsigned long action, void *hcpu) |
| 337 | { |
| 338 | unsigned int cpu = (unsigned long) hcpu; |
| 339 | |
| 340 | switch (action) { |
| 341 | case CPU_ONLINE: |
Rafael J. Wysocki | 8bb7844 | 2007-05-09 02:35:10 -0700 | [diff] [blame] | 342 | case CPU_ONLINE_FROZEN: |
Rudolf Marek | bebe467 | 2007-05-08 17:22:02 +0200 | [diff] [blame] | 343 | coretemp_device_add(cpu); |
| 344 | break; |
| 345 | case CPU_DEAD: |
Rafael J. Wysocki | 8bb7844 | 2007-05-09 02:35:10 -0700 | [diff] [blame] | 346 | case CPU_DEAD_FROZEN: |
Rudolf Marek | bebe467 | 2007-05-08 17:22:02 +0200 | [diff] [blame] | 347 | coretemp_device_remove(cpu); |
| 348 | break; |
| 349 | } |
| 350 | return NOTIFY_OK; |
| 351 | } |
| 352 | |
| 353 | static struct notifier_block __cpuinitdata coretemp_cpu_notifier = { |
| 354 | .notifier_call = coretemp_cpu_callback, |
| 355 | }; |
| 356 | #endif /* !CONFIG_HOTPLUG_CPU */ |
| 357 | |
| 358 | static int __init coretemp_init(void) |
| 359 | { |
| 360 | int i, err = -ENODEV; |
| 361 | struct pdev_entry *p, *n; |
| 362 | |
Rudolf Marek | bebe467 | 2007-05-08 17:22:02 +0200 | [diff] [blame] | 363 | /* quick check if we run Intel */ |
| 364 | if (cpu_data[0].x86_vendor != X86_VENDOR_INTEL) |
| 365 | goto exit; |
| 366 | |
| 367 | err = platform_driver_register(&coretemp_driver); |
| 368 | if (err) |
| 369 | goto exit; |
| 370 | |
| 371 | for_each_online_cpu(i) { |
| 372 | struct cpuinfo_x86 *c = &(cpu_data)[i]; |
| 373 | |
| 374 | /* check if family 6, models e, f */ |
| 375 | if ((c->cpuid_level < 0) || (c->x86 != 0x6) || |
| 376 | !((c->x86_model == 0xe) || (c->x86_model == 0xf))) { |
| 377 | |
| 378 | /* supported CPU not found, but report the unknown |
| 379 | family 6 CPU */ |
| 380 | if ((c->x86 == 0x6) && (c->x86_model > 0xf)) |
| 381 | printk(KERN_WARNING DRVNAME ": Unknown CPU " |
| 382 | "model %x\n", c->x86_model); |
| 383 | continue; |
| 384 | } |
| 385 | |
| 386 | err = coretemp_device_add(i); |
| 387 | if (err) |
| 388 | goto exit_devices_unreg; |
| 389 | } |
| 390 | if (list_empty(&pdev_list)) { |
| 391 | err = -ENODEV; |
| 392 | goto exit_driver_unreg; |
| 393 | } |
| 394 | |
| 395 | #ifdef CONFIG_HOTPLUG_CPU |
| 396 | register_hotcpu_notifier(&coretemp_cpu_notifier); |
| 397 | #endif |
| 398 | return 0; |
| 399 | |
| 400 | exit_devices_unreg: |
| 401 | mutex_lock(&pdev_list_mutex); |
| 402 | list_for_each_entry_safe(p, n, &pdev_list, list) { |
| 403 | platform_device_unregister(p->pdev); |
| 404 | list_del(&p->list); |
| 405 | kfree(p); |
| 406 | } |
| 407 | mutex_unlock(&pdev_list_mutex); |
| 408 | exit_driver_unreg: |
| 409 | platform_driver_unregister(&coretemp_driver); |
| 410 | exit: |
| 411 | return err; |
| 412 | } |
| 413 | |
| 414 | static void __exit coretemp_exit(void) |
| 415 | { |
| 416 | struct pdev_entry *p, *n; |
| 417 | #ifdef CONFIG_HOTPLUG_CPU |
| 418 | unregister_hotcpu_notifier(&coretemp_cpu_notifier); |
| 419 | #endif |
| 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 | platform_driver_unregister(&coretemp_driver); |
| 428 | } |
| 429 | |
| 430 | MODULE_AUTHOR("Rudolf Marek <r.marek@assembler.cz>"); |
| 431 | MODULE_DESCRIPTION("Intel Core temperature monitor"); |
| 432 | MODULE_LICENSE("GPL"); |
| 433 | |
| 434 | module_init(coretemp_init) |
| 435 | module_exit(coretemp_exit) |