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 41 #define DRVNAME "via_cputemp" 42 43 enum { SHOW_TEMP, SHOW_LABEL, SHOW_NAME }; 44 45 /* 46 * Functions declaration 47 */ 48 49 struct via_cputemp_data { 50 struct device *hwmon_dev; 51 const char *name; 52 u8 vrm; 53 u32 id; 54 u32 msr_temp; 55 u32 msr_vid; 56 }; 57 58 /* 59 * Sysfs stuff 60 */ 61 62 static ssize_t show_name(struct device *dev, struct device_attribute 63 *devattr, char *buf) 64 { 65 int ret; 66 struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr); 67 struct via_cputemp_data *data = dev_get_drvdata(dev); 68 69 if (attr->index == SHOW_NAME) 70 ret = sprintf(buf, "%s\n", data->name); 71 else /* show label */ 72 ret = sprintf(buf, "Core %d\n", data->id); 73 return ret; 74 } 75 76 static ssize_t show_temp(struct device *dev, 77 struct device_attribute *devattr, char *buf) 78 { 79 struct via_cputemp_data *data = dev_get_drvdata(dev); 80 u32 eax, edx; 81 int err; 82 83 err = rdmsr_safe_on_cpu(data->id, data->msr_temp, &eax, &edx); 84 if (err) 85 return -EAGAIN; 86 87 return sprintf(buf, "%lu\n", ((unsigned long)eax & 0xffffff) * 1000); 88 } 89 90 static ssize_t show_cpu_vid(struct device *dev, 91 struct device_attribute *devattr, char *buf) 92 { 93 struct via_cputemp_data *data = dev_get_drvdata(dev); 94 u32 eax, edx; 95 int err; 96 97 err = rdmsr_safe_on_cpu(data->id, data->msr_vid, &eax, &edx); 98 if (err) 99 return -EAGAIN; 100 101 return sprintf(buf, "%d\n", vid_from_reg(~edx & 0x7f, data->vrm)); 102 } 103 104 static SENSOR_DEVICE_ATTR(temp1_input, S_IRUGO, show_temp, NULL, 105 SHOW_TEMP); 106 static SENSOR_DEVICE_ATTR(temp1_label, S_IRUGO, show_name, NULL, SHOW_LABEL); 107 static SENSOR_DEVICE_ATTR(name, S_IRUGO, show_name, NULL, SHOW_NAME); 108 109 static struct attribute *via_cputemp_attributes[] = { 110 &sensor_dev_attr_name.dev_attr.attr, 111 &sensor_dev_attr_temp1_label.dev_attr.attr, 112 &sensor_dev_attr_temp1_input.dev_attr.attr, 113 NULL 114 }; 115 116 static const struct attribute_group via_cputemp_group = { 117 .attrs = via_cputemp_attributes, 118 }; 119 120 /* Optional attributes */ 121 static DEVICE_ATTR(cpu0_vid, S_IRUGO, show_cpu_vid, NULL); 122 123 static int __devinit via_cputemp_probe(struct platform_device *pdev) 124 { 125 struct via_cputemp_data *data; 126 struct cpuinfo_x86 *c = &cpu_data(pdev->id); 127 int err; 128 u32 eax, edx; 129 130 data = kzalloc(sizeof(struct via_cputemp_data), GFP_KERNEL); 131 if (!data) { 132 err = -ENOMEM; 133 dev_err(&pdev->dev, "Out of memory\n"); 134 goto exit; 135 } 136 137 data->id = pdev->id; 138 data->name = "via_cputemp"; 139 140 switch (c->x86_model) { 141 case 0xA: 142 /* C7 A */ 143 case 0xD: 144 /* C7 D */ 145 data->msr_temp = 0x1169; 146 data->msr_vid = 0x198; 147 break; 148 case 0xF: 149 /* Nano */ 150 data->msr_temp = 0x1423; 151 break; 152 default: 153 err = -ENODEV; 154 goto exit_free; 155 } 156 157 /* test if we can access the TEMPERATURE MSR */ 158 err = rdmsr_safe_on_cpu(data->id, data->msr_temp, &eax, &edx); 159 if (err) { 160 dev_err(&pdev->dev, 161 "Unable to access TEMPERATURE MSR, giving up\n"); 162 goto exit_free; 163 } 164 165 platform_set_drvdata(pdev, data); 166 167 err = sysfs_create_group(&pdev->dev.kobj, &via_cputemp_group); 168 if (err) 169 goto exit_free; 170 171 if (data->msr_vid) 172 data->vrm = vid_which_vrm(); 173 174 if (data->vrm) { 175 err = device_create_file(&pdev->dev, &dev_attr_cpu0_vid); 176 if (err) 177 goto exit_remove; 178 } 179 180 data->hwmon_dev = hwmon_device_register(&pdev->dev); 181 if (IS_ERR(data->hwmon_dev)) { 182 err = PTR_ERR(data->hwmon_dev); 183 dev_err(&pdev->dev, "Class registration failed (%d)\n", 184 err); 185 goto exit_remove; 186 } 187 188 return 0; 189 190 exit_remove: 191 if (data->vrm) 192 device_remove_file(&pdev->dev, &dev_attr_cpu0_vid); 193 sysfs_remove_group(&pdev->dev.kobj, &via_cputemp_group); 194 exit_free: 195 platform_set_drvdata(pdev, NULL); 196 kfree(data); 197 exit: 198 return err; 199 } 200 201 static int __devexit via_cputemp_remove(struct platform_device *pdev) 202 { 203 struct via_cputemp_data *data = platform_get_drvdata(pdev); 204 205 hwmon_device_unregister(data->hwmon_dev); 206 if (data->vrm) 207 device_remove_file(&pdev->dev, &dev_attr_cpu0_vid); 208 sysfs_remove_group(&pdev->dev.kobj, &via_cputemp_group); 209 platform_set_drvdata(pdev, NULL); 210 kfree(data); 211 return 0; 212 } 213 214 static struct platform_driver via_cputemp_driver = { 215 .driver = { 216 .owner = THIS_MODULE, 217 .name = DRVNAME, 218 }, 219 .probe = via_cputemp_probe, 220 .remove = __devexit_p(via_cputemp_remove), 221 }; 222 223 struct pdev_entry { 224 struct list_head list; 225 struct platform_device *pdev; 226 unsigned int cpu; 227 }; 228 229 static LIST_HEAD(pdev_list); 230 static DEFINE_MUTEX(pdev_list_mutex); 231 232 static int __cpuinit via_cputemp_device_add(unsigned int cpu) 233 { 234 int err; 235 struct platform_device *pdev; 236 struct pdev_entry *pdev_entry; 237 238 pdev = platform_device_alloc(DRVNAME, cpu); 239 if (!pdev) { 240 err = -ENOMEM; 241 pr_err("Device allocation failed\n"); 242 goto exit; 243 } 244 245 pdev_entry = kzalloc(sizeof(struct pdev_entry), GFP_KERNEL); 246 if (!pdev_entry) { 247 err = -ENOMEM; 248 goto exit_device_put; 249 } 250 251 err = platform_device_add(pdev); 252 if (err) { 253 pr_err("Device addition failed (%d)\n", err); 254 goto exit_device_free; 255 } 256 257 pdev_entry->pdev = pdev; 258 pdev_entry->cpu = cpu; 259 mutex_lock(&pdev_list_mutex); 260 list_add_tail(&pdev_entry->list, &pdev_list); 261 mutex_unlock(&pdev_list_mutex); 262 263 return 0; 264 265 exit_device_free: 266 kfree(pdev_entry); 267 exit_device_put: 268 platform_device_put(pdev); 269 exit: 270 return err; 271 } 272 273 static void __cpuinit via_cputemp_device_remove(unsigned int cpu) 274 { 275 struct pdev_entry *p; 276 277 mutex_lock(&pdev_list_mutex); 278 list_for_each_entry(p, &pdev_list, list) { 279 if (p->cpu == cpu) { 280 platform_device_unregister(p->pdev); 281 list_del(&p->list); 282 mutex_unlock(&pdev_list_mutex); 283 kfree(p); 284 return; 285 } 286 } 287 mutex_unlock(&pdev_list_mutex); 288 } 289 290 static int __cpuinit via_cputemp_cpu_callback(struct notifier_block *nfb, 291 unsigned long action, void *hcpu) 292 { 293 unsigned int cpu = (unsigned long) hcpu; 294 295 switch (action) { 296 case CPU_ONLINE: 297 case CPU_DOWN_FAILED: 298 via_cputemp_device_add(cpu); 299 break; 300 case CPU_DOWN_PREPARE: 301 via_cputemp_device_remove(cpu); 302 break; 303 } 304 return NOTIFY_OK; 305 } 306 307 static struct notifier_block via_cputemp_cpu_notifier __refdata = { 308 .notifier_call = via_cputemp_cpu_callback, 309 }; 310 311 static int __init via_cputemp_init(void) 312 { 313 int i, err; 314 315 if (cpu_data(0).x86_vendor != X86_VENDOR_CENTAUR) { 316 printk(KERN_DEBUG DRVNAME ": Not a VIA CPU\n"); 317 err = -ENODEV; 318 goto exit; 319 } 320 321 err = platform_driver_register(&via_cputemp_driver); 322 if (err) 323 goto exit; 324 325 for_each_online_cpu(i) { 326 struct cpuinfo_x86 *c = &cpu_data(i); 327 328 if (c->x86 != 6) 329 continue; 330 331 if (c->x86_model < 0x0a) 332 continue; 333 334 if (c->x86_model > 0x0f) { 335 pr_warn("Unknown CPU model 0x%x\n", c->x86_model); 336 continue; 337 } 338 339 via_cputemp_device_add(i); 340 } 341 342 #ifndef CONFIG_HOTPLUG_CPU 343 if (list_empty(&pdev_list)) { 344 err = -ENODEV; 345 goto exit_driver_unreg; 346 } 347 #endif 348 349 register_hotcpu_notifier(&via_cputemp_cpu_notifier); 350 return 0; 351 352 #ifndef CONFIG_HOTPLUG_CPU 353 exit_driver_unreg: 354 platform_driver_unregister(&via_cputemp_driver); 355 #endif 356 exit: 357 return err; 358 } 359 360 static void __exit via_cputemp_exit(void) 361 { 362 struct pdev_entry *p, *n; 363 364 unregister_hotcpu_notifier(&via_cputemp_cpu_notifier); 365 mutex_lock(&pdev_list_mutex); 366 list_for_each_entry_safe(p, n, &pdev_list, list) { 367 platform_device_unregister(p->pdev); 368 list_del(&p->list); 369 kfree(p); 370 } 371 mutex_unlock(&pdev_list_mutex); 372 platform_driver_unregister(&via_cputemp_driver); 373 } 374 375 MODULE_AUTHOR("Harald Welte <HaraldWelte@viatech.com>"); 376 MODULE_DESCRIPTION("VIA CPU temperature monitor"); 377 MODULE_LICENSE("GPL"); 378 379 module_init(via_cputemp_init) 380 module_exit(via_cputemp_exit) 381