drivers/hwmon/k8temp.c

   1 /*
   2  * k8temp.c - Linux kernel module for hardware monitoring
   3  *
   4  * Copyright (C) 2006 Rudolf Marek <r.marek@assembler.cz>
   5  *
   6  * Inspired from the w83785 and amd756 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; either version 2 of the License, or
  11  * (at your option) any later version.
  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 #include <linux/module.h>
  25 #include <linux/init.h>
  26 #include <linux/slab.h>
  27 #include <linux/jiffies.h>
  28 #include <linux/pci.h>
  29 #include <linux/hwmon.h>
  30 #include <linux/hwmon-sysfs.h>
  31 #include <linux/err.h>
  32 #include <linux/mutex.h>
  33 #include <asm/processor.h>
  34
  35 #define TEMP_FROM_REG(val)      (((((val) >> 16) & 0xff) - 49) * 1000)
  36 #define REG_TEMP        0xe4
  37 #define SEL_PLACE       0x40
  38 #define SEL_CORE        0x04
  39
  40 struct k8temp_data {
  41         struct device *hwmon_dev;
  42         struct mutex update_lock;
  43         const char *name;
  44         char valid;             /* zero until following fields are valid */
  45         unsigned long last_updated;     /* in jiffies */
  46
  47         /* registers values */
  48         u8 sensorsp;            /* sensor presence bits - SEL_CORE, SEL_PLACE */
  49         u32 temp[2][2];         /* core, place */
  50         u8 swap_core_select;    /* meaning of SEL_CORE is inverted */
  51         u32 temp_offset;
  52 };
  53
  54 static struct k8temp_data *k8temp_update_device(struct device *dev)
  55 {
  56         struct k8temp_data *data = dev_get_drvdata(dev);
  57         struct pci_dev *pdev = to_pci_dev(dev);
  58         u8 tmp;
  59
  60         mutex_lock(&data->update_lock);
  61
  62         if (!data->valid
  63             || time_after(jiffies, data->last_updated + HZ)) {
  64                 pci_read_config_byte(pdev, REG_TEMP, &tmp);
  65                 tmp &= ~(SEL_PLACE | SEL_CORE); /* Select sensor 0, core0 */
  66                 pci_write_config_byte(pdev, REG_TEMP, tmp);
  67                 pci_read_config_dword(pdev, REG_TEMP, &data->temp[0][0]);
  68
  69                 if (data->sensorsp & SEL_PLACE) {
  70                         tmp |= SEL_PLACE;       /* Select sensor 1, core0 */
  71                         pci_write_config_byte(pdev, REG_TEMP, tmp);
  72                         pci_read_config_dword(pdev, REG_TEMP,
  73                                               &data->temp[0][1]);
  74                 }
  75
  76                 if (data->sensorsp & SEL_CORE) {
  77                         tmp &= ~SEL_PLACE;      /* Select sensor 0, core1 */
  78                         tmp |= SEL_CORE;
  79                         pci_write_config_byte(pdev, REG_TEMP, tmp);
  80                         pci_read_config_dword(pdev, REG_TEMP,
  81                                               &data->temp[1][0]);
  82
  83                         if (data->sensorsp & SEL_PLACE) {
  84                                 tmp |= SEL_PLACE; /* Select sensor 1, core1 */
  85                                 pci_write_config_byte(pdev, REG_TEMP, tmp);
  86                                 pci_read_config_dword(pdev, REG_TEMP,
  87                                                       &data->temp[1][1]);
  88                         }
  89                 }
  90
  91                 data->last_updated = jiffies;
  92                 data->valid = 1;
  93         }
  94
  95         mutex_unlock(&data->update_lock);
  96         return data;
  97 }
  98
  99 /*
 100  * Sysfs stuff
 101  */
 102
 103 static ssize_t name_show(struct device *dev, struct device_attribute
 104                          *devattr, char *buf)
 105 {
 106         struct k8temp_data *data = dev_get_drvdata(dev);
 107
 108         return sprintf(buf, "%s\n", data->name);
 109 }
 110
 111
 112 static ssize_t temp_show(struct device *dev, struct device_attribute *devattr,
 113                          char *buf)
 114 {
 115         struct sensor_device_attribute_2 *attr =
 116             to_sensor_dev_attr_2(devattr);
 117         int core = attr->nr;
 118         int place = attr->index;
 119         int temp;
 120         struct k8temp_data *data = k8temp_update_device(dev);
 121
 122         if (data->swap_core_select && (data->sensorsp & SEL_CORE))
 123                 core = core ? 0 : 1;
 124
 125         temp = TEMP_FROM_REG(data->temp[core][place]) + data->temp_offset;
 126
 127         return sprintf(buf, "%d\n", temp);
 128 }
 129
 130 /* core, place */
 131
 132 static SENSOR_DEVICE_ATTR_2_RO(temp1_input, temp, 0, 0);
 133 static SENSOR_DEVICE_ATTR_2_RO(temp2_input, temp, 0, 1);
 134 static SENSOR_DEVICE_ATTR_2_RO(temp3_input, temp, 1, 0);
 135 static SENSOR_DEVICE_ATTR_2_RO(temp4_input, temp, 1, 1);
 136 static DEVICE_ATTR_RO(name);
 137
 138 static const struct pci_device_id k8temp_ids[] = {
 139         { PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_K8_NB_MISC) },
 140         { 0 },
 141 };
 142
 143 MODULE_DEVICE_TABLE(pci, k8temp_ids);
 144
 145 static int is_rev_g_desktop(u8 model)
 146 {
 147         u32 brandidx;
 148
 149         if (model < 0x69)
 150                 return 0;
 151
 152         if (model == 0xc1 || model == 0x6c || model == 0x7c)
 153                 return 0;
 154
 155         /*
 156          * Differentiate between AM2 and ASB1.
 157          * See "Constructing the processor Name String" in "Revision
 158          * Guide for AMD NPT Family 0Fh Processors" (33610).
 159          */
 160         brandidx = cpuid_ebx(0x80000001);
 161         brandidx = (brandidx >> 9) & 0x1f;
 162
 163         /* Single core */
 164         if ((model == 0x6f || model == 0x7f) &&
 165             (brandidx == 0x7 || brandidx == 0x9 || brandidx == 0xc))
 166                 return 0;
 167
 168         /* Dual core */
 169         if (model == 0x6b &&
 170             (brandidx == 0xb || brandidx == 0xc))
 171                 return 0;
 172
 173         return 1;
 174 }
 175
 176 static int k8temp_probe(struct pci_dev *pdev,
 177                                   const struct pci_device_id *id)
 178 {
 179         int err;
 180         u8 scfg;
 181         u32 temp;
 182         u8 model, stepping;
 183         struct k8temp_data *data;
 184
 185         data = devm_kzalloc(&pdev->dev, sizeof(struct k8temp_data), GFP_KERNEL);
 186         if (!data)
 187                 return -ENOMEM;
 188
 189         model = boot_cpu_data.x86_model;
 190         stepping = boot_cpu_data.x86_stepping;
 191
 192         /* feature available since SH-C0, exclude older revisions */
 193         if ((model == 4 && stepping == 0) ||
 194             (model == 5 && stepping <= 1))
 195                 return -ENODEV;
 196
 197         /*
 198          * AMD NPT family 0fh, i.e. RevF and RevG:
 199          * meaning of SEL_CORE bit is inverted
 200          */
 201         if (model >= 0x40) {
 202                 data->swap_core_select = 1;
 203                 dev_warn(&pdev->dev,
 204                          "Temperature readouts might be wrong - check erratum #141\n");
 205         }
 206
 207         /*
 208          * RevG desktop CPUs (i.e. no socket S1G1 or ASB1 parts) need
 209          * additional offset, otherwise reported temperature is below
 210          * ambient temperature
 211          */
 212         if (is_rev_g_desktop(model))
 213                 data->temp_offset = 21000;
 214
 215         pci_read_config_byte(pdev, REG_TEMP, &scfg);
 216         scfg &= ~(SEL_PLACE | SEL_CORE);        /* Select sensor 0, core0 */
 217         pci_write_config_byte(pdev, REG_TEMP, scfg);
 218         pci_read_config_byte(pdev, REG_TEMP, &scfg);
 219
 220         if (scfg & (SEL_PLACE | SEL_CORE)) {
 221                 dev_err(&pdev->dev, "Configuration bit(s) stuck at 1!\n");
 222                 return -ENODEV;
 223         }
 224
 225         scfg |= (SEL_PLACE | SEL_CORE);
 226         pci_write_config_byte(pdev, REG_TEMP, scfg);
 227
 228         /* now we know if we can change core and/or sensor */
 229         pci_read_config_byte(pdev, REG_TEMP, &data->sensorsp);
 230
 231         if (data->sensorsp & SEL_PLACE) {
 232                 scfg &= ~SEL_CORE;      /* Select sensor 1, core0 */
 233                 pci_write_config_byte(pdev, REG_TEMP, scfg);
 234                 pci_read_config_dword(pdev, REG_TEMP, &temp);
 235                 scfg |= SEL_CORE;       /* prepare for next selection */
 236                 if (!((temp >> 16) & 0xff)) /* if temp is 0 -49C is unlikely */
 237                         data->sensorsp &= ~SEL_PLACE;
 238         }
 239
 240         if (data->sensorsp & SEL_CORE) {
 241                 scfg &= ~SEL_PLACE;     /* Select sensor 0, core1 */
 242                 pci_write_config_byte(pdev, REG_TEMP, scfg);
 243                 pci_read_config_dword(pdev, REG_TEMP, &temp);
 244                 if (!((temp >> 16) & 0xff)) /* if temp is 0 -49C is unlikely */
 245                         data->sensorsp &= ~SEL_CORE;
 246         }
 247
 248         data->name = "k8temp";
 249         mutex_init(&data->update_lock);
 250         pci_set_drvdata(pdev, data);
 251
 252         /* Register sysfs hooks */
 253         err = device_create_file(&pdev->dev,
 254                            &sensor_dev_attr_temp1_input.dev_attr);
 255         if (err)
 256                 goto exit_remove;
 257
 258         /* sensor can be changed and reports something */
 259         if (data->sensorsp & SEL_PLACE) {
 260                 err = device_create_file(&pdev->dev,
 261                                    &sensor_dev_attr_temp2_input.dev_attr);
 262                 if (err)
 263                         goto exit_remove;
 264         }
 265
 266         /* core can be changed and reports something */
 267         if (data->sensorsp & SEL_CORE) {
 268                 err = device_create_file(&pdev->dev,
 269                                    &sensor_dev_attr_temp3_input.dev_attr);
 270                 if (err)
 271                         goto exit_remove;
 272                 if (data->sensorsp & SEL_PLACE) {
 273                         err = device_create_file(&pdev->dev,
 274                                            &sensor_dev_attr_temp4_input.
 275                                            dev_attr);
 276                         if (err)
 277                                 goto exit_remove;
 278                 }
 279         }
 280
 281         err = device_create_file(&pdev->dev, &dev_attr_name);
 282         if (err)
 283                 goto exit_remove;
 284
 285         data->hwmon_dev = hwmon_device_register(&pdev->dev);
 286
 287         if (IS_ERR(data->hwmon_dev)) {
 288                 err = PTR_ERR(data->hwmon_dev);
 289                 goto exit_remove;
 290         }
 291
 292         return 0;
 293
 294 exit_remove:
 295         device_remove_file(&pdev->dev,
 296                            &sensor_dev_attr_temp1_input.dev_attr);
 297         device_remove_file(&pdev->dev,
 298                            &sensor_dev_attr_temp2_input.dev_attr);
 299         device_remove_file(&pdev->dev,
 300                            &sensor_dev_attr_temp3_input.dev_attr);
 301         device_remove_file(&pdev->dev,
 302                            &sensor_dev_attr_temp4_input.dev_attr);
 303         device_remove_file(&pdev->dev, &dev_attr_name);
 304         return err;
 305 }
 306
 307 static void k8temp_remove(struct pci_dev *pdev)
 308 {
 309         struct k8temp_data *data = pci_get_drvdata(pdev);
 310
 311         hwmon_device_unregister(data->hwmon_dev);
 312         device_remove_file(&pdev->dev,
 313                            &sensor_dev_attr_temp1_input.dev_attr);
 314         device_remove_file(&pdev->dev,
 315                            &sensor_dev_attr_temp2_input.dev_attr);
 316         device_remove_file(&pdev->dev,
 317                            &sensor_dev_attr_temp3_input.dev_attr);
 318         device_remove_file(&pdev->dev,
 319                            &sensor_dev_attr_temp4_input.dev_attr);
 320         device_remove_file(&pdev->dev, &dev_attr_name);
 321 }
 322
 323 static struct pci_driver k8temp_driver = {
 324         .name = "k8temp",
 325         .id_table = k8temp_ids,
 326         .probe = k8temp_probe,
 327         .remove = k8temp_remove,
 328 };
 329
 330 module_pci_driver(k8temp_driver);
 331
 332 MODULE_AUTHOR("Rudolf Marek <r.marek@assembler.cz>");
 333 MODULE_DESCRIPTION("AMD K8 core temperature monitor");
 334 MODULE_LICENSE("GPL");