1 /* 2 * via-cputemp.c - Driver for VIA CPU core temperature monitoring 3 * Copyright (C) 2009 VIA Technologies, Inc. 4 * 5 * based on existing coretemp.c, which is 6 * 7 * Copyright (C) 2007 Rudolf Marek <r.marek@assembler.cz> 8 * 9 * This program is free software; you can redistribute it and/or modify 10 * it under the terms of the GNU General Public License as published by 11 * the Free Software Foundation; version 2 of the License. 12 * 13 * This program is distributed in the hope that it will be useful, 14 * but WITHOUT ANY WARRANTY; without even the implied warranty of 15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 16 * GNU General Public License for more details. 17 * 18 * You should have received a copy of the GNU General Public License 19 * along with this program; if not, write to the Free Software 20 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 21 * 02110-1301 USA. 22 */ 23 24 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt 25 26 #include <linux/module.h> 27 #include <linux/init.h> 28 #include <linux/slab.h> 29 #include <linux/hwmon.h> 30 #include <linux/hwmon-vid.h> 31 #include <linux/sysfs.h> 32 #include <linux/hwmon-sysfs.h> 33 #include <linux/err.h> 34 #include <linux/mutex.h> 35 #include <linux/list.h> 36 #include <linux/platform_device.h> 37 #include <linux/cpu.h> 38 #include <asm/msr.h> 39 #include <asm/processor.h> 40 #include <asm/cpu_device_id.h> 41 42 #define DRVNAME "via_cputemp" 43 44 enum { SHOW_TEMP, SHOW_LABEL, SHOW_NAME }; 45 46 /* 47 * Functions declaration 48 */ 49 50 struct via_cputemp_data { 51 struct device *hwmon_dev; 52 const char *name; 53 u8 vrm; 54 u32 id; 55 u32 msr_temp; 56 u32 msr_vid; 57 }; 58 59 /* 60 * Sysfs stuff 61 */ 62 63 static ssize_t show_name(struct device *dev, struct device_attribute 64 *devattr, char *buf) 65 { 66 int ret; 67 struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr); 68 struct via_cputemp_data *data = dev_get_drvdata(dev); 69 70 if (attr->index == SHOW_NAME) 71 ret = sprintf(buf, "%s\n", data->name); 72 else /* show label */ 73 ret = sprintf(buf, "Core %d\n", data->id); 74 return ret; 75 } 76 77 static ssize_t show_temp(struct device *dev, 78 struct device_attribute *devattr, char *buf) 79 { 80 struct via_cputemp_data *data = dev_get_drvdata(dev); 81 u32 eax, edx; 82 int err; 83 84 err = rdmsr_safe_on_cpu(data->id, data->msr_temp, &eax, &edx); 85 if (err) 86 return -EAGAIN; 87 88 return sprintf(buf, "%lu\n", ((unsigned long)eax & 0xffffff) * 1000); 89 } 90 91 static ssize_t show_cpu_vid(struct device *dev, 92 struct device_attribute *devattr, char *buf) 93 { 94 struct via_cputemp_data *data = dev_get_drvdata(dev); 95 u32 eax, edx; 96 int err; 97 98 err = rdmsr_safe_on_cpu(data->id, data->msr_vid, &eax, &edx); 99 if (err) 100 return -EAGAIN; 101 102 return sprintf(buf, "%d\n", vid_from_reg(~edx & 0x7f, data->vrm)); 103 } 104 105 static SENSOR_DEVICE_ATTR(temp1_input, S_IRUGO, show_temp, NULL, 106 SHOW_TEMP); 107 static SENSOR_DEVICE_ATTR(temp1_label, S_IRUGO, show_name, NULL, SHOW_LABEL); 108 static SENSOR_DEVICE_ATTR(name, S_IRUGO, show_name, NULL, SHOW_NAME); 109 110 static struct attribute *via_cputemp_attributes[] = { 111 &sensor_dev_attr_name.dev_attr.attr, 112 &sensor_dev_attr_temp1_label.dev_attr.attr, 113 &sensor_dev_attr_temp1_input.dev_attr.attr, 114 NULL 115 }; 116 117 static const struct attribute_group via_cputemp_group = { 118 .attrs = via_cputemp_attributes, 119 }; 120 121 /* Optional attributes */ 122 static DEVICE_ATTR(cpu0_vid, S_IRUGO, show_cpu_vid, NULL); 123 124 static int __devinit via_cputemp_probe(struct platform_device *pdev) 125 { 126 struct via_cputemp_data *data; 127 struct cpuinfo_x86 *c = &cpu_data(pdev->id); 128 int err; 129 u32 eax, edx; 130 131 data = kzalloc(sizeof(struct via_cputemp_data), GFP_KERNEL); 132 if (!data) { 133 err = -ENOMEM; 134 dev_err(&pdev->dev, "Out of memory\n"); 135 goto exit; 136 } 137 138 data->id = pdev->id; 139 data->name = "via_cputemp"; 140 141 switch (c->x86_model) { 142 case 0xA: 143 /* C7 A */ 144 case 0xD: 145 /* C7 D */ 146 data->msr_temp = 0x1169; 147 data->msr_vid = 0x198; 148 break; 149 case 0xF: 150 /* Nano */ 151 data->msr_temp = 0x1423; 152 break; 153 default: 154 err = -ENODEV; 155 goto exit_free; 156 } 157 158 /* test if we can access the TEMPERATURE MSR */ 159 err = rdmsr_safe_on_cpu(data->id, data->msr_temp, &eax, &edx); 160 if (err) { 161 dev_err(&pdev->dev, 162 "Unable to access TEMPERATURE MSR, giving up\n"); 163 goto exit_free; 164 } 165 166 platform_set_drvdata(pdev, data); 167 168 err = sysfs_create_group(&pdev->dev.kobj, &via_cputemp_group); 169 if (err) 170 goto exit_free; 171 172 if (data->msr_vid) 173 data->vrm = vid_which_vrm(); 174 175 if (data->vrm) { 176 err = device_create_file(&pdev->dev, &dev_attr_cpu0_vid); 177 if (err) 178 goto exit_remove; 179 } 180 181 data->hwmon_dev = hwmon_device_register(&pdev->dev); 182 if (IS_ERR(data->hwmon_dev)) { 183 err = PTR_ERR(data->hwmon_dev); 184 dev_err(&pdev->dev, "Class registration failed (%d)\n", 185 err); 186 goto exit_remove; 187 } 188 189 return 0; 190 191 exit_remove: 192 if (data->vrm) 193 device_remove_file(&pdev->dev, &dev_attr_cpu0_vid); 194 sysfs_remove_group(&pdev->dev.kobj, &via_cputemp_group); 195 exit_free: 196 platform_set_drvdata(pdev, NULL); 197 kfree(data); 198 exit: 199 return err; 200 } 201 202 static int __devexit via_cputemp_remove(struct platform_device *pdev) 203 { 204 struct via_cputemp_data *data = platform_get_drvdata(pdev); 205 206 hwmon_device_unregister(data->hwmon_dev); 207 if (data->vrm) 208 device_remove_file(&pdev->dev, &dev_attr_cpu0_vid); 209 sysfs_remove_group(&pdev->dev.kobj, &via_cputemp_group); 210 platform_set_drvdata(pdev, NULL); 211 kfree(data); 212 return 0; 213 } 214 215 static struct platform_driver via_cputemp_driver = { 216 .driver = { 217 .owner = THIS_MODULE, 218 .name = DRVNAME, 219 }, 220 .probe = via_cputemp_probe, 221 .remove = __devexit_p(via_cputemp_remove), 222 }; 223 224 struct pdev_entry { 225 struct list_head list; 226 struct platform_device *pdev; 227 unsigned int cpu; 228 }; 229 230 static LIST_HEAD(pdev_list); 231 static DEFINE_MUTEX(pdev_list_mutex); 232 233 static int __cpuinit via_cputemp_device_add(unsigned int cpu) 234 { 235 int err; 236 struct platform_device *pdev; 237 struct pdev_entry *pdev_entry; 238 239 pdev = platform_device_alloc(DRVNAME, cpu); 240 if (!pdev) { 241 err = -ENOMEM; 242 pr_err("Device allocation failed\n"); 243 goto exit; 244 } 245 246 pdev_entry = kzalloc(sizeof(struct pdev_entry), GFP_KERNEL); 247 if (!pdev_entry) { 248 err = -ENOMEM; 249 goto exit_device_put; 250 } 251 252 err = platform_device_add(pdev); 253 if (err) { 254 pr_err("Device addition failed (%d)\n", err); 255 goto exit_device_free; 256 } 257 258 pdev_entry->pdev = pdev; 259 pdev_entry->cpu = cpu; 260 mutex_lock(&pdev_list_mutex); 261 list_add_tail(&pdev_entry->list, &pdev_list); 262 mutex_unlock(&pdev_list_mutex); 263 264 return 0; 265 266 exit_device_free: 267 kfree(pdev_entry); 268 exit_device_put: 269 platform_device_put(pdev); 270 exit: 271 return err; 272 } 273 274 static void __cpuinit via_cputemp_device_remove(unsigned int cpu) 275 { 276 struct pdev_entry *p; 277 278 mutex_lock(&pdev_list_mutex); 279 list_for_each_entry(p, &pdev_list, list) { 280 if (p->cpu == cpu) { 281 platform_device_unregister(p->pdev); 282 list_del(&p->list); 283 mutex_unlock(&pdev_list_mutex); 284 kfree(p); 285 return; 286 } 287 } 288 mutex_unlock(&pdev_list_mutex); 289 } 290 291 static int __cpuinit via_cputemp_cpu_callback(struct notifier_block *nfb, 292 unsigned long action, void *hcpu) 293 { 294 unsigned int cpu = (unsigned long) hcpu; 295 296 switch (action) { 297 case CPU_ONLINE: 298 case CPU_DOWN_FAILED: 299 via_cputemp_device_add(cpu); 300 break; 301 case CPU_DOWN_PREPARE: 302 via_cputemp_device_remove(cpu); 303 break; 304 } 305 return NOTIFY_OK; 306 } 307 308 static struct notifier_block via_cputemp_cpu_notifier __refdata = { 309 .notifier_call = via_cputemp_cpu_callback, 310 }; 311 312 static const struct x86_cpu_id cputemp_ids[] = { 313 { X86_VENDOR_CENTAUR, 6, 0xa, }, /* C7 A */ 314 { X86_VENDOR_CENTAUR, 6, 0xd, }, /* C7 D */ 315 { X86_VENDOR_CENTAUR, 6, 0xf, }, /* Nano */ 316 {} 317 }; 318 MODULE_DEVICE_TABLE(x86cpu, cputemp_ids); 319 320 static int __init via_cputemp_init(void) 321 { 322 int i, err; 323 324 if (!x86_match_cpu(cputemp_ids)) 325 return -ENODEV; 326 327 err = platform_driver_register(&via_cputemp_driver); 328 if (err) 329 goto exit; 330 331 for_each_online_cpu(i) { 332 struct cpuinfo_x86 *c = &cpu_data(i); 333 334 if (c->x86 != 6) 335 continue; 336 337 if (c->x86_model < 0x0a) 338 continue; 339 340 if (c->x86_model > 0x0f) { 341 pr_warn("Unknown CPU model 0x%x\n", c->x86_model); 342 continue; 343 } 344 345 via_cputemp_device_add(i); 346 } 347 348 #ifndef CONFIG_HOTPLUG_CPU 349 if (list_empty(&pdev_list)) { 350 err = -ENODEV; 351 goto exit_driver_unreg; 352 } 353 #endif 354 355 register_hotcpu_notifier(&via_cputemp_cpu_notifier); 356 return 0; 357 358 #ifndef CONFIG_HOTPLUG_CPU 359 exit_driver_unreg: 360 platform_driver_unregister(&via_cputemp_driver); 361 #endif 362 exit: 363 return err; 364 } 365 366 static void __exit via_cputemp_exit(void) 367 { 368 struct pdev_entry *p, *n; 369 370 unregister_hotcpu_notifier(&via_cputemp_cpu_notifier); 371 mutex_lock(&pdev_list_mutex); 372 list_for_each_entry_safe(p, n, &pdev_list, list) { 373 platform_device_unregister(p->pdev); 374 list_del(&p->list); 375 kfree(p); 376 } 377 mutex_unlock(&pdev_list_mutex); 378 platform_driver_unregister(&via_cputemp_driver); 379 } 380 381 MODULE_AUTHOR("Harald Welte <HaraldWelte@viatech.com>"); 382 MODULE_DESCRIPTION("VIA CPU temperature monitor"); 383 MODULE_LICENSE("GPL"); 384 385 module_init(via_cputemp_init) 386 module_exit(via_cputemp_exit) 387