drivers/hwmon/i5k_amb.c

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2 /*
   3  * A hwmon driver for the Intel 5000 series chipset FB-DIMM AMB
   4  * temperature sensors
   5  * Copyright (C) 2007 IBM
   6  *
   7  * Author: Darrick J. Wong <darrick.wong@oracle.com>
   8  */
   9
  10 #include <linux/module.h>
  11 #include <linux/hwmon.h>
  12 #include <linux/hwmon-sysfs.h>
  13 #include <linux/err.h>
  14 #include <linux/mutex.h>
  15 #include <linux/log2.h>
  16 #include <linux/pci.h>
  17 #include <linux/platform_device.h>
  18 #include <linux/slab.h>
  19
  20 #define DRVNAME "i5k_amb"
  21
  22 #define I5K_REG_AMB_BASE_ADDR           0x48
  23 #define I5K_REG_AMB_LEN_ADDR            0x50
  24 #define I5K_REG_CHAN0_PRESENCE_ADDR     0x64
  25 #define I5K_REG_CHAN1_PRESENCE_ADDR     0x66
  26
  27 #define AMB_REG_TEMP_MIN_ADDR           0x80
  28 #define AMB_REG_TEMP_MID_ADDR           0x81
  29 #define AMB_REG_TEMP_MAX_ADDR           0x82
  30 #define AMB_REG_TEMP_STATUS_ADDR        0x84
  31 #define AMB_REG_TEMP_ADDR               0x85
  32
  33 #define AMB_CONFIG_SIZE                 2048
  34 #define AMB_FUNC_3_OFFSET               768
  35
  36 static unsigned long amb_reg_temp_status(unsigned int amb)
  37 {
  38         return AMB_FUNC_3_OFFSET + AMB_REG_TEMP_STATUS_ADDR +
  39                AMB_CONFIG_SIZE * amb;
  40 }
  41
  42 static unsigned long amb_reg_temp_min(unsigned int amb)
  43 {
  44         return AMB_FUNC_3_OFFSET + AMB_REG_TEMP_MIN_ADDR +
  45                AMB_CONFIG_SIZE * amb;
  46 }
  47
  48 static unsigned long amb_reg_temp_mid(unsigned int amb)
  49 {
  50         return AMB_FUNC_3_OFFSET + AMB_REG_TEMP_MID_ADDR +
  51                AMB_CONFIG_SIZE * amb;
  52 }
  53
  54 static unsigned long amb_reg_temp_max(unsigned int amb)
  55 {
  56         return AMB_FUNC_3_OFFSET + AMB_REG_TEMP_MAX_ADDR +
  57                AMB_CONFIG_SIZE * amb;
  58 }
  59
  60 static unsigned long amb_reg_temp(unsigned int amb)
  61 {
  62         return AMB_FUNC_3_OFFSET + AMB_REG_TEMP_ADDR +
  63                AMB_CONFIG_SIZE * amb;
  64 }
  65
  66 #define MAX_MEM_CHANNELS                4
  67 #define MAX_AMBS_PER_CHANNEL            16
  68 #define MAX_AMBS                        (MAX_MEM_CHANNELS * \
  69                                          MAX_AMBS_PER_CHANNEL)
  70 #define CHANNEL_SHIFT                   4
  71 #define DIMM_MASK                       0xF
  72 /*
  73  * Ugly hack: For some reason the highest bit is set if there
  74  * are _any_ DIMMs in the channel.  Attempting to read from
  75  * this "high-order" AMB results in a memory bus error, so
  76  * for now we'll just ignore that top bit, even though that
  77  * might prevent us from seeing the 16th DIMM in the channel.
  78  */
  79 #define REAL_MAX_AMBS_PER_CHANNEL       15
  80 #define KNOBS_PER_AMB                   6
  81
  82 static unsigned long amb_num_from_reg(unsigned int byte_num, unsigned int bit)
  83 {
  84         return byte_num * MAX_AMBS_PER_CHANNEL + bit;
  85 }
  86
  87 #define AMB_SYSFS_NAME_LEN              16
  88 struct i5k_device_attribute {
  89         struct sensor_device_attribute s_attr;
  90         char name[AMB_SYSFS_NAME_LEN];
  91 };
  92
  93 struct i5k_amb_data {
  94         struct device *hwmon_dev;
  95
  96         unsigned long amb_base;
  97         unsigned long amb_len;
  98         u16 amb_present[MAX_MEM_CHANNELS];
  99         void __iomem *amb_mmio;
 100         struct i5k_device_attribute *attrs;
 101         unsigned int num_attrs;
 102 };
 103
 104 static DEVICE_STRING_ATTR_RO(name, 0444, DRVNAME);
 105
 106 static struct platform_device *amb_pdev;
 107
 108 static u8 amb_read_byte(struct i5k_amb_data *data, unsigned long offset)
 109 {
 110         return ioread8(data->amb_mmio + offset);
 111 }
 112
 113 static void amb_write_byte(struct i5k_amb_data *data, unsigned long offset,
 114                            u8 val)
 115 {
 116         iowrite8(val, data->amb_mmio + offset);
 117 }
 118
 119 static ssize_t show_amb_alarm(struct device *dev,
 120                              struct device_attribute *devattr,
 121                              char *buf)
 122 {
 123         struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
 124         struct i5k_amb_data *data = dev_get_drvdata(dev);
 125
 126         if (!(amb_read_byte(data, amb_reg_temp_status(attr->index)) & 0x20) &&
 127              (amb_read_byte(data, amb_reg_temp_status(attr->index)) & 0x8))
 128                 return sprintf(buf, "1\n");
 129         else
 130                 return sprintf(buf, "0\n");
 131 }
 132
 133 static ssize_t store_amb_min(struct device *dev,
 134                              struct device_attribute *devattr,
 135                              const char *buf,
 136                              size_t count)
 137 {
 138         struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
 139         struct i5k_amb_data *data = dev_get_drvdata(dev);
 140         unsigned long temp;
 141         int ret = kstrtoul(buf, 10, &temp);
 142         if (ret < 0)
 143                 return ret;
 144
 145         temp = temp / 500;
 146         if (temp > 255)
 147                 temp = 255;
 148
 149         amb_write_byte(data, amb_reg_temp_min(attr->index), temp);
 150         return count;
 151 }
 152
 153 static ssize_t store_amb_mid(struct device *dev,
 154                              struct device_attribute *devattr,
 155                              const char *buf,
 156                              size_t count)
 157 {
 158         struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
 159         struct i5k_amb_data *data = dev_get_drvdata(dev);
 160         unsigned long temp;
 161         int ret = kstrtoul(buf, 10, &temp);
 162         if (ret < 0)
 163                 return ret;
 164
 165         temp = temp / 500;
 166         if (temp > 255)
 167                 temp = 255;
 168
 169         amb_write_byte(data, amb_reg_temp_mid(attr->index), temp);
 170         return count;
 171 }
 172
 173 static ssize_t store_amb_max(struct device *dev,
 174                              struct device_attribute *devattr,
 175                              const char *buf,
 176                              size_t count)
 177 {
 178         struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
 179         struct i5k_amb_data *data = dev_get_drvdata(dev);
 180         unsigned long temp;
 181         int ret = kstrtoul(buf, 10, &temp);
 182         if (ret < 0)
 183                 return ret;
 184
 185         temp = temp / 500;
 186         if (temp > 255)
 187                 temp = 255;
 188
 189         amb_write_byte(data, amb_reg_temp_max(attr->index), temp);
 190         return count;
 191 }
 192
 193 static ssize_t show_amb_min(struct device *dev,
 194                              struct device_attribute *devattr,
 195                              char *buf)
 196 {
 197         struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
 198         struct i5k_amb_data *data = dev_get_drvdata(dev);
 199         return sprintf(buf, "%d\n",
 200                 500 * amb_read_byte(data, amb_reg_temp_min(attr->index)));
 201 }
 202
 203 static ssize_t show_amb_mid(struct device *dev,
 204                              struct device_attribute *devattr,
 205                              char *buf)
 206 {
 207         struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
 208         struct i5k_amb_data *data = dev_get_drvdata(dev);
 209         return sprintf(buf, "%d\n",
 210                 500 * amb_read_byte(data, amb_reg_temp_mid(attr->index)));
 211 }
 212
 213 static ssize_t show_amb_max(struct device *dev,
 214                              struct device_attribute *devattr,
 215                              char *buf)
 216 {
 217         struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
 218         struct i5k_amb_data *data = dev_get_drvdata(dev);
 219         return sprintf(buf, "%d\n",
 220                 500 * amb_read_byte(data, amb_reg_temp_max(attr->index)));
 221 }
 222
 223 static ssize_t show_amb_temp(struct device *dev,
 224                              struct device_attribute *devattr,
 225                              char *buf)
 226 {
 227         struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
 228         struct i5k_amb_data *data = dev_get_drvdata(dev);
 229         return sprintf(buf, "%d\n",
 230                 500 * amb_read_byte(data, amb_reg_temp(attr->index)));
 231 }
 232
 233 static ssize_t show_label(struct device *dev,
 234                           struct device_attribute *devattr,
 235                           char *buf)
 236 {
 237         struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
 238
 239         return sprintf(buf, "Ch. %d DIMM %d\n", attr->index >> CHANNEL_SHIFT,
 240                        attr->index & DIMM_MASK);
 241 }
 242
 243 static int i5k_amb_hwmon_init(struct platform_device *pdev)
 244 {
 245         int i, j, k, d = 0;
 246         u16 c;
 247         int res = 0;
 248         int num_ambs = 0;
 249         struct i5k_amb_data *data = platform_get_drvdata(pdev);
 250
 251         /* Count the number of AMBs found */
 252         /* ignore the high-order bit, see "Ugly hack" comment above */
 253         for (i = 0; i < MAX_MEM_CHANNELS; i++)
 254                 num_ambs += hweight16(data->amb_present[i] & 0x7fff);
 255
 256         /* Set up sysfs stuff */
 257         data->attrs = kzalloc(array3_size(num_ambs, KNOBS_PER_AMB,
 258                                           sizeof(*data->attrs)),
 259                               GFP_KERNEL);
 260         if (!data->attrs)
 261                 return -ENOMEM;
 262         data->num_attrs = 0;
 263
 264         for (i = 0; i < MAX_MEM_CHANNELS; i++) {
 265                 c = data->amb_present[i];
 266                 for (j = 0; j < REAL_MAX_AMBS_PER_CHANNEL; j++, c >>= 1) {
 267                         struct i5k_device_attribute *iattr;
 268
 269                         k = amb_num_from_reg(i, j);
 270                         if (!(c & 0x1))
 271                                 continue;
 272                         d++;
 273
 274                         /* sysfs label */
 275                         iattr = data->attrs + data->num_attrs;
 276                         snprintf(iattr->name, AMB_SYSFS_NAME_LEN,
 277                                  "temp%d_label", d);
 278                         iattr->s_attr.dev_attr.attr.name = iattr->name;
 279                         iattr->s_attr.dev_attr.attr.mode = 0444;
 280                         iattr->s_attr.dev_attr.show = show_label;
 281                         iattr->s_attr.index = k;
 282                         sysfs_attr_init(&iattr->s_attr.dev_attr.attr);
 283                         res = device_create_file(&pdev->dev,
 284                                                  &iattr->s_attr.dev_attr);
 285                         if (res)
 286                                 goto exit_remove;
 287                         data->num_attrs++;
 288
 289                         /* Temperature sysfs knob */
 290                         iattr = data->attrs + data->num_attrs;
 291                         snprintf(iattr->name, AMB_SYSFS_NAME_LEN,
 292                                  "temp%d_input", d);
 293                         iattr->s_attr.dev_attr.attr.name = iattr->name;
 294                         iattr->s_attr.dev_attr.attr.mode = 0444;
 295                         iattr->s_attr.dev_attr.show = show_amb_temp;
 296                         iattr->s_attr.index = k;
 297                         sysfs_attr_init(&iattr->s_attr.dev_attr.attr);
 298                         res = device_create_file(&pdev->dev,
 299                                                  &iattr->s_attr.dev_attr);
 300                         if (res)
 301                                 goto exit_remove;
 302                         data->num_attrs++;
 303
 304                         /* Temperature min sysfs knob */
 305                         iattr = data->attrs + data->num_attrs;
 306                         snprintf(iattr->name, AMB_SYSFS_NAME_LEN,
 307                                  "temp%d_min", d);
 308                         iattr->s_attr.dev_attr.attr.name = iattr->name;
 309                         iattr->s_attr.dev_attr.attr.mode = 0644;
 310                         iattr->s_attr.dev_attr.show = show_amb_min;
 311                         iattr->s_attr.dev_attr.store = store_amb_min;
 312                         iattr->s_attr.index = k;
 313                         sysfs_attr_init(&iattr->s_attr.dev_attr.attr);
 314                         res = device_create_file(&pdev->dev,
 315                                                  &iattr->s_attr.dev_attr);
 316                         if (res)
 317                                 goto exit_remove;
 318                         data->num_attrs++;
 319
 320                         /* Temperature mid sysfs knob */
 321                         iattr = data->attrs + data->num_attrs;
 322                         snprintf(iattr->name, AMB_SYSFS_NAME_LEN,
 323                                  "temp%d_mid", d);
 324                         iattr->s_attr.dev_attr.attr.name = iattr->name;
 325                         iattr->s_attr.dev_attr.attr.mode = 0644;
 326                         iattr->s_attr.dev_attr.show = show_amb_mid;
 327                         iattr->s_attr.dev_attr.store = store_amb_mid;
 328                         iattr->s_attr.index = k;
 329                         sysfs_attr_init(&iattr->s_attr.dev_attr.attr);
 330                         res = device_create_file(&pdev->dev,
 331                                                  &iattr->s_attr.dev_attr);
 332                         if (res)
 333                                 goto exit_remove;
 334                         data->num_attrs++;
 335
 336                         /* Temperature max sysfs knob */
 337                         iattr = data->attrs + data->num_attrs;
 338                         snprintf(iattr->name, AMB_SYSFS_NAME_LEN,
 339                                  "temp%d_max", d);
 340                         iattr->s_attr.dev_attr.attr.name = iattr->name;
 341                         iattr->s_attr.dev_attr.attr.mode = 0644;
 342                         iattr->s_attr.dev_attr.show = show_amb_max;
 343                         iattr->s_attr.dev_attr.store = store_amb_max;
 344                         iattr->s_attr.index = k;
 345                         sysfs_attr_init(&iattr->s_attr.dev_attr.attr);
 346                         res = device_create_file(&pdev->dev,
 347                                                  &iattr->s_attr.dev_attr);
 348                         if (res)
 349                                 goto exit_remove;
 350                         data->num_attrs++;
 351
 352                         /* Temperature alarm sysfs knob */
 353                         iattr = data->attrs + data->num_attrs;
 354                         snprintf(iattr->name, AMB_SYSFS_NAME_LEN,
 355                                  "temp%d_alarm", d);
 356                         iattr->s_attr.dev_attr.attr.name = iattr->name;
 357                         iattr->s_attr.dev_attr.attr.mode = 0444;
 358                         iattr->s_attr.dev_attr.show = show_amb_alarm;
 359                         iattr->s_attr.index = k;
 360                         sysfs_attr_init(&iattr->s_attr.dev_attr.attr);
 361                         res = device_create_file(&pdev->dev,
 362                                                  &iattr->s_attr.dev_attr);
 363                         if (res)
 364                                 goto exit_remove;
 365                         data->num_attrs++;
 366                 }
 367         }
 368
 369         res = device_create_file(&pdev->dev, &dev_attr_name.attr);
 370         if (res)
 371                 goto exit_remove;
 372
 373         data->hwmon_dev = hwmon_device_register(&pdev->dev);
 374         if (IS_ERR(data->hwmon_dev)) {
 375                 res = PTR_ERR(data->hwmon_dev);
 376                 goto exit_remove;
 377         }
 378
 379         return res;
 380
 381 exit_remove:
 382         device_remove_file(&pdev->dev, &dev_attr_name.attr);
 383         for (i = 0; i < data->num_attrs; i++)
 384                 device_remove_file(&pdev->dev, &data->attrs[i].s_attr.dev_attr);
 385         kfree(data->attrs);
 386
 387         return res;
 388 }
 389
 390 static int i5k_amb_add(void)
 391 {
 392         int res;
 393
 394         /* only ever going to be one of these */
 395         amb_pdev = platform_device_alloc(DRVNAME, 0);
 396         if (!amb_pdev)
 397                 return -ENOMEM;
 398
 399         res = platform_device_add(amb_pdev);
 400         if (res)
 401                 goto err;
 402         return 0;
 403
 404 err:
 405         platform_device_put(amb_pdev);
 406         return res;
 407 }
 408
 409 static int i5k_find_amb_registers(struct i5k_amb_data *data,
 410                                             unsigned long devid)
 411 {
 412         struct pci_dev *pcidev;
 413         u32 val32;
 414         int res = -ENODEV;
 415
 416         /* Find AMB register memory space */
 417         pcidev = pci_get_device(PCI_VENDOR_ID_INTEL,
 418                                 devid,
 419                                 NULL);
 420         if (!pcidev)
 421                 return -ENODEV;
 422
 423         pci_read_config_dword(pcidev, I5K_REG_AMB_BASE_ADDR, &val32);
 424         if (val32 == (u32)~0)
 425                 goto out;
 426         data->amb_base = val32;
 427
 428         pci_read_config_dword(pcidev, I5K_REG_AMB_LEN_ADDR, &val32);
 429         if (val32 == (u32)~0)
 430                 goto out;
 431         data->amb_len = val32;
 432
 433         /* Is it big enough? */
 434         if (data->amb_len < AMB_CONFIG_SIZE * MAX_AMBS) {
 435                 dev_err(&pcidev->dev, "AMB region too small!\n");
 436                 goto out;
 437         }
 438
 439         res = 0;
 440 out:
 441         pci_dev_put(pcidev);
 442         return res;
 443 }
 444
 445 static int i5k_channel_probe(u16 *amb_present, unsigned long dev_id)
 446 {
 447         struct pci_dev *pcidev;
 448         u16 val16;
 449         int res = -ENODEV;
 450
 451         /* Copy the DIMM presence map for these two channels */
 452         pcidev = pci_get_device(PCI_VENDOR_ID_INTEL, dev_id, NULL);
 453         if (!pcidev)
 454                 return -ENODEV;
 455
 456         pci_read_config_word(pcidev, I5K_REG_CHAN0_PRESENCE_ADDR, &val16);
 457         if (val16 == (u16)~0)
 458                 goto out;
 459         amb_present[0] = val16;
 460
 461         pci_read_config_word(pcidev, I5K_REG_CHAN1_PRESENCE_ADDR, &val16);
 462         if (val16 == (u16)~0)
 463                 goto out;
 464         amb_present[1] = val16;
 465
 466         res = 0;
 467
 468 out:
 469         pci_dev_put(pcidev);
 470         return res;
 471 }
 472
 473 static struct {
 474         unsigned long err;
 475         unsigned long fbd0;
 476 } chipset_ids[]  = {
 477         { PCI_DEVICE_ID_INTEL_5000_ERR, PCI_DEVICE_ID_INTEL_5000_FBD0 },
 478         { PCI_DEVICE_ID_INTEL_5400_ERR, PCI_DEVICE_ID_INTEL_5400_FBD0 },
 479         { 0, 0 }
 480 };
 481
 482 #ifdef MODULE
 483 static const struct pci_device_id i5k_amb_ids[] = {
 484         { PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_5000_ERR) },
 485         { PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_5400_ERR) },
 486         { 0, }
 487 };
 488 MODULE_DEVICE_TABLE(pci, i5k_amb_ids);
 489 #endif
 490
 491 static int i5k_amb_probe(struct platform_device *pdev)
 492 {
 493         struct i5k_amb_data *data;
 494         struct resource *reso;
 495         int i, res;
 496
 497         data = kzalloc(sizeof(*data), GFP_KERNEL);
 498         if (!data)
 499                 return -ENOMEM;
 500
 501         /* Figure out where the AMB registers live */
 502         i = 0;
 503         do {
 504                 res = i5k_find_amb_registers(data, chipset_ids[i].err);
 505                 if (res == 0)
 506                         break;
 507                 i++;
 508         } while (chipset_ids[i].err);
 509
 510         if (res)
 511                 goto err;
 512
 513         /* Copy the DIMM presence map for the first two channels */
 514         res = i5k_channel_probe(&data->amb_present[0], chipset_ids[i].fbd0);
 515         if (res)
 516                 goto err;
 517
 518         /* Copy the DIMM presence map for the optional second two channels */
 519         i5k_channel_probe(&data->amb_present[2], chipset_ids[i].fbd0 + 1);
 520
 521         /* Set up resource regions */
 522         reso = request_mem_region(data->amb_base, data->amb_len, DRVNAME);
 523         if (!reso) {
 524                 res = -EBUSY;
 525                 goto err;
 526         }
 527
 528         data->amb_mmio = ioremap(data->amb_base, data->amb_len);
 529         if (!data->amb_mmio) {
 530                 res = -EBUSY;
 531                 goto err_map_failed;
 532         }
 533
 534         platform_set_drvdata(pdev, data);
 535
 536         res = i5k_amb_hwmon_init(pdev);
 537         if (res)
 538                 goto err_init_failed;
 539
 540         return res;
 541
 542 err_init_failed:
 543         iounmap(data->amb_mmio);
 544 err_map_failed:
 545         release_mem_region(data->amb_base, data->amb_len);
 546 err:
 547         kfree(data);
 548         return res;
 549 }
 550
 551 static void i5k_amb_remove(struct platform_device *pdev)
 552 {
 553         int i;
 554         struct i5k_amb_data *data = platform_get_drvdata(pdev);
 555
 556         hwmon_device_unregister(data->hwmon_dev);
 557         device_remove_file(&pdev->dev, &dev_attr_name.attr);
 558         for (i = 0; i < data->num_attrs; i++)
 559                 device_remove_file(&pdev->dev, &data->attrs[i].s_attr.dev_attr);
 560         kfree(data->attrs);
 561         iounmap(data->amb_mmio);
 562         release_mem_region(data->amb_base, data->amb_len);
 563         kfree(data);
 564 }
 565
 566 static struct platform_driver i5k_amb_driver = {
 567         .driver = {
 568                 .name = DRVNAME,
 569         },
 570         .probe = i5k_amb_probe,
 571         .remove = i5k_amb_remove,
 572 };
 573
 574 static int __init i5k_amb_init(void)
 575 {
 576         int res;
 577
 578         res = platform_driver_register(&i5k_amb_driver);
 579         if (res)
 580                 return res;
 581
 582         res = i5k_amb_add();
 583         if (res)
 584                 platform_driver_unregister(&i5k_amb_driver);
 585
 586         return res;
 587 }
 588
 589 static void __exit i5k_amb_exit(void)
 590 {
 591         platform_device_unregister(amb_pdev);
 592         platform_driver_unregister(&i5k_amb_driver);
 593 }
 594
 595 MODULE_AUTHOR("Darrick J. Wong <darrick.wong@oracle.com>");
 596 MODULE_DESCRIPTION("Intel 5000 chipset FB-DIMM AMB temperature sensor");
 597 MODULE_LICENSE("GPL");
 598
 599 module_init(i5k_amb_init);
 600 module_exit(i5k_amb_exit);