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Version: [ 2.6.11.8 ] [ 2.6.25 ] [ 2.6.25.8 ] [ 2.6.31.13 ] Architecture: [ i386 ]
  1 /*
  2  * A hwmon driver for the Intel 5000 series chipset FB-DIMM AMB
  3  * temperature sensors
  4  * Copyright (C) 2007 IBM
  5  *
  6  * Author: Darrick J. Wong <djwong@us.ibm.com>
  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., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 21  */
 22 
 23 #include <linux/module.h>
 24 #include <linux/jiffies.h>
 25 #include <linux/hwmon.h>
 26 #include <linux/hwmon-sysfs.h>
 27 #include <linux/err.h>
 28 #include <linux/mutex.h>
 29 #include <linux/delay.h>
 30 #include <linux/log2.h>
 31 #include <linux/pci.h>
 32 #include <linux/platform_device.h>
 33 
 34 #define DRVNAME "i5k_amb"
 35 
 36 #define I5K_REG_AMB_BASE_ADDR           0x48
 37 #define I5K_REG_AMB_LEN_ADDR            0x50
 38 #define I5K_REG_CHAN0_PRESENCE_ADDR     0x64
 39 #define I5K_REG_CHAN1_PRESENCE_ADDR     0x66
 40 
 41 #define AMB_REG_TEMP_MIN_ADDR           0x80
 42 #define AMB_REG_TEMP_MID_ADDR           0x81
 43 #define AMB_REG_TEMP_MAX_ADDR           0x82
 44 #define AMB_REG_TEMP_STATUS_ADDR        0x84
 45 #define AMB_REG_TEMP_ADDR               0x85
 46 
 47 #define AMB_CONFIG_SIZE                 2048
 48 #define AMB_FUNC_3_OFFSET               768
 49 
 50 static unsigned long amb_reg_temp_status(unsigned int amb)
 51 {
 52         return AMB_FUNC_3_OFFSET + AMB_REG_TEMP_STATUS_ADDR +
 53                AMB_CONFIG_SIZE * amb;
 54 }
 55 
 56 static unsigned long amb_reg_temp_min(unsigned int amb)
 57 {
 58         return AMB_FUNC_3_OFFSET + AMB_REG_TEMP_MIN_ADDR +
 59                AMB_CONFIG_SIZE * amb;
 60 }
 61 
 62 static unsigned long amb_reg_temp_mid(unsigned int amb)
 63 {
 64         return AMB_FUNC_3_OFFSET + AMB_REG_TEMP_MID_ADDR +
 65                AMB_CONFIG_SIZE * amb;
 66 }
 67 
 68 static unsigned long amb_reg_temp_max(unsigned int amb)
 69 {
 70         return AMB_FUNC_3_OFFSET + AMB_REG_TEMP_MAX_ADDR +
 71                AMB_CONFIG_SIZE * amb;
 72 }
 73 
 74 static unsigned long amb_reg_temp(unsigned int amb)
 75 {
 76         return AMB_FUNC_3_OFFSET + AMB_REG_TEMP_ADDR +
 77                AMB_CONFIG_SIZE * amb;
 78 }
 79 
 80 #define MAX_MEM_CHANNELS                4
 81 #define MAX_AMBS_PER_CHANNEL            16
 82 #define MAX_AMBS                        (MAX_MEM_CHANNELS * \
 83                                          MAX_AMBS_PER_CHANNEL)
 84 /*
 85  * Ugly hack: For some reason the highest bit is set if there
 86  * are _any_ DIMMs in the channel.  Attempting to read from
 87  * this "high-order" AMB results in a memory bus error, so
 88  * for now we'll just ignore that top bit, even though that
 89  * might prevent us from seeing the 16th DIMM in the channel.
 90  */
 91 #define REAL_MAX_AMBS_PER_CHANNEL       15
 92 #define KNOBS_PER_AMB                   5
 93 
 94 static unsigned long amb_num_from_reg(unsigned int byte_num, unsigned int bit)
 95 {
 96         return byte_num * MAX_AMBS_PER_CHANNEL + bit;
 97 }
 98 
 99 #define AMB_SYSFS_NAME_LEN              16
100 struct i5k_device_attribute {
101         struct sensor_device_attribute s_attr;
102         char name[AMB_SYSFS_NAME_LEN];
103 };
104 
105 struct i5k_amb_data {
106         struct device *hwmon_dev;
107 
108         unsigned long amb_base;
109         unsigned long amb_len;
110         u16 amb_present[MAX_MEM_CHANNELS];
111         void __iomem *amb_mmio;
112         struct i5k_device_attribute *attrs;
113         unsigned int num_attrs;
114 };
115 
116 static ssize_t show_name(struct device *dev, struct device_attribute *devattr,
117                          char *buf)
118 {
119         return sprintf(buf, "%s\n", DRVNAME);
120 }
121 
122 
123 static DEVICE_ATTR(name, S_IRUGO, show_name, NULL);
124 
125 static struct platform_device *amb_pdev;
126 
127 static u8 amb_read_byte(struct i5k_amb_data *data, unsigned long offset)
128 {
129         return ioread8(data->amb_mmio + offset);
130 }
131 
132 static void amb_write_byte(struct i5k_amb_data *data, unsigned long offset,
133                            u8 val)
134 {
135         iowrite8(val, data->amb_mmio + offset);
136 }
137 
138 static ssize_t show_amb_alarm(struct device *dev,
139                              struct device_attribute *devattr,
140                              char *buf)
141 {
142         struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
143         struct i5k_amb_data *data = dev_get_drvdata(dev);
144 
145         if (!(amb_read_byte(data, amb_reg_temp_status(attr->index)) & 0x20) &&
146              (amb_read_byte(data, amb_reg_temp_status(attr->index)) & 0x8))
147                 return sprintf(buf, "1\n");
148         else
149                 return sprintf(buf, "\n");
150 }
151 
152 static ssize_t store_amb_min(struct device *dev,
153                              struct device_attribute *devattr,
154                              const char *buf,
155                              size_t count)
156 {
157         struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
158         struct i5k_amb_data *data = dev_get_drvdata(dev);
159         unsigned long temp = simple_strtoul(buf, NULL, 10) / 500;
160 
161         if (temp > 255)
162                 temp = 255;
163 
164         amb_write_byte(data, amb_reg_temp_min(attr->index), temp);
165         return count;
166 }
167 
168 static ssize_t store_amb_mid(struct device *dev,
169                              struct device_attribute *devattr,
170                              const char *buf,
171                              size_t count)
172 {
173         struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
174         struct i5k_amb_data *data = dev_get_drvdata(dev);
175         unsigned long temp = simple_strtoul(buf, NULL, 10) / 500;
176 
177         if (temp > 255)
178                 temp = 255;
179 
180         amb_write_byte(data, amb_reg_temp_mid(attr->index), temp);
181         return count;
182 }
183 
184 static ssize_t store_amb_max(struct device *dev,
185                              struct device_attribute *devattr,
186                              const char *buf,
187                              size_t count)
188 {
189         struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
190         struct i5k_amb_data *data = dev_get_drvdata(dev);
191         unsigned long temp = simple_strtoul(buf, NULL, 10) / 500;
192 
193         if (temp > 255)
194                 temp = 255;
195 
196         amb_write_byte(data, amb_reg_temp_max(attr->index), temp);
197         return count;
198 }
199 
200 static ssize_t show_amb_min(struct device *dev,
201                              struct device_attribute *devattr,
202                              char *buf)
203 {
204         struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
205         struct i5k_amb_data *data = dev_get_drvdata(dev);
206         return sprintf(buf, "%d\n",
207                 500 * amb_read_byte(data, amb_reg_temp_min(attr->index)));
208 }
209 
210 static ssize_t show_amb_mid(struct device *dev,
211                              struct device_attribute *devattr,
212                              char *buf)
213 {
214         struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
215         struct i5k_amb_data *data = dev_get_drvdata(dev);
216         return sprintf(buf, "%d\n",
217                 500 * amb_read_byte(data, amb_reg_temp_mid(attr->index)));
218 }
219 
220 static ssize_t show_amb_max(struct device *dev,
221                              struct device_attribute *devattr,
222                              char *buf)
223 {
224         struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
225         struct i5k_amb_data *data = dev_get_drvdata(dev);
226         return sprintf(buf, "%d\n",
227                 500 * amb_read_byte(data, amb_reg_temp_max(attr->index)));
228 }
229 
230 static ssize_t show_amb_temp(struct device *dev,
231                              struct device_attribute *devattr,
232                              char *buf)
233 {
234         struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
235         struct i5k_amb_data *data = dev_get_drvdata(dev);
236         return sprintf(buf, "%d\n",
237                 500 * amb_read_byte(data, amb_reg_temp(attr->index)));
238 }
239 
240 static int __devinit i5k_amb_hwmon_init(struct platform_device *pdev)
241 {
242         int i, j, k, d = 0;
243         u16 c;
244         int res = 0;
245         int num_ambs = 0;
246         struct i5k_amb_data *data = platform_get_drvdata(pdev);
247 
248         /* Count the number of AMBs found */
249         /* ignore the high-order bit, see "Ugly hack" comment above */
250         for (i = 0; i < MAX_MEM_CHANNELS; i++)
251                 num_ambs += hweight16(data->amb_present[i] & 0x7fff);
252 
253         /* Set up sysfs stuff */
254         data->attrs = kzalloc(sizeof(*data->attrs) * num_ambs * KNOBS_PER_AMB,
255                                 GFP_KERNEL);
256         if (!data->attrs)
257                 return -ENOMEM;
258         data->num_attrs = 0;
259 
260         for (i = 0; i < MAX_MEM_CHANNELS; i++) {
261                 c = data->amb_present[i];
262                 for (j = 0; j < REAL_MAX_AMBS_PER_CHANNEL; j++, c >>= 1) {
263                         struct i5k_device_attribute *iattr;
264 
265                         k = amb_num_from_reg(i, j);
266                         if (!(c & 0x1))
267                                 continue;
268                         d++;
269 
270                         /* Temperature sysfs knob */
271                         iattr = data->attrs + data->num_attrs;
272                         snprintf(iattr->name, AMB_SYSFS_NAME_LEN,
273                                  "temp%d_input", d);
274                         iattr->s_attr.dev_attr.attr.name = iattr->name;
275                         iattr->s_attr.dev_attr.attr.mode = S_IRUGO;
276                         iattr->s_attr.dev_attr.show = show_amb_temp;
277                         iattr->s_attr.index = k;
278                         res = device_create_file(&pdev->dev,
279                                                  &iattr->s_attr.dev_attr);
280                         if (res)
281                                 goto exit_remove;
282                         data->num_attrs++;
283 
284                         /* Temperature min sysfs knob */
285                         iattr = data->attrs + data->num_attrs;
286                         snprintf(iattr->name, AMB_SYSFS_NAME_LEN,
287                                  "temp%d_min", d);
288                         iattr->s_attr.dev_attr.attr.name = iattr->name;
289                         iattr->s_attr.dev_attr.attr.mode = S_IWUSR | S_IRUGO;
290                         iattr->s_attr.dev_attr.show = show_amb_min;
291                         iattr->s_attr.dev_attr.store = store_amb_min;
292                         iattr->s_attr.index = k;
293                         res = device_create_file(&pdev->dev,
294                                                  &iattr->s_attr.dev_attr);
295                         if (res)
296                                 goto exit_remove;
297                         data->num_attrs++;
298 
299                         /* Temperature mid sysfs knob */
300                         iattr = data->attrs + data->num_attrs;
301                         snprintf(iattr->name, AMB_SYSFS_NAME_LEN,
302                                  "temp%d_mid", d);
303                         iattr->s_attr.dev_attr.attr.name = iattr->name;
304                         iattr->s_attr.dev_attr.attr.mode = S_IWUSR | S_IRUGO;
305                         iattr->s_attr.dev_attr.show = show_amb_mid;
306                         iattr->s_attr.dev_attr.store = store_amb_mid;
307                         iattr->s_attr.index = k;
308                         res = device_create_file(&pdev->dev,
309                                                  &iattr->s_attr.dev_attr);
310                         if (res)
311                                 goto exit_remove;
312                         data->num_attrs++;
313 
314                         /* Temperature max sysfs knob */
315                         iattr = data->attrs + data->num_attrs;
316                         snprintf(iattr->name, AMB_SYSFS_NAME_LEN,
317                                  "temp%d_max", d);
318                         iattr->s_attr.dev_attr.attr.name = iattr->name;
319                         iattr->s_attr.dev_attr.attr.mode = S_IWUSR | S_IRUGO;
320                         iattr->s_attr.dev_attr.show = show_amb_max;
321                         iattr->s_attr.dev_attr.store = store_amb_max;
322                         iattr->s_attr.index = k;
323                         res = device_create_file(&pdev->dev,
324                                                  &iattr->s_attr.dev_attr);
325                         if (res)
326                                 goto exit_remove;
327                         data->num_attrs++;
328 
329                         /* Temperature alarm sysfs knob */
330                         iattr = data->attrs + data->num_attrs;
331                         snprintf(iattr->name, AMB_SYSFS_NAME_LEN,
332                                  "temp%d_alarm", d);
333                         iattr->s_attr.dev_attr.attr.name = iattr->name;
334                         iattr->s_attr.dev_attr.attr.mode = S_IRUGO;
335                         iattr->s_attr.dev_attr.show = show_amb_alarm;
336                         iattr->s_attr.index = k;
337                         res = device_create_file(&pdev->dev,
338                                                  &iattr->s_attr.dev_attr);
339                         if (res)
340                                 goto exit_remove;
341                         data->num_attrs++;
342                 }
343         }
344 
345         res = device_create_file(&pdev->dev, &dev_attr_name);
346         if (res)
347                 goto exit_remove;
348 
349         data->hwmon_dev = hwmon_device_register(&pdev->dev);
350         if (IS_ERR(data->hwmon_dev)) {
351                 res = PTR_ERR(data->hwmon_dev);
352                 goto exit_remove;
353         }
354 
355         return res;
356 
357 exit_remove:
358         device_remove_file(&pdev->dev, &dev_attr_name);
359         for (i = 0; i < data->num_attrs; i++)
360                 device_remove_file(&pdev->dev, &data->attrs[i].s_attr.dev_attr);
361         kfree(data->attrs);
362 
363         return res;
364 }
365 
366 static int __devinit i5k_amb_add(void)
367 {
368         int res = -ENODEV;
369 
370         /* only ever going to be one of these */
371         amb_pdev = platform_device_alloc(DRVNAME, 0);
372         if (!amb_pdev)
373                 return -ENOMEM;
374 
375         res = platform_device_add(amb_pdev);
376         if (res)
377                 goto err;
378         return 0;
379 
380 err:
381         platform_device_put(amb_pdev);
382         return res;
383 }
384 
385 static int __devinit i5k_find_amb_registers(struct i5k_amb_data *data)
386 {
387         struct pci_dev *pcidev;
388         u32 val32;
389         int res = -ENODEV;
390 
391         /* Find AMB register memory space */
392         pcidev = pci_get_device(PCI_VENDOR_ID_INTEL,
393                                 PCI_DEVICE_ID_INTEL_5000_ERR,
394                                 NULL);
395         if (!pcidev)
396                 return -ENODEV;
397 
398         if (pci_read_config_dword(pcidev, I5K_REG_AMB_BASE_ADDR, &val32))
399                 goto out;
400         data->amb_base = val32;
401 
402         if (pci_read_config_dword(pcidev, I5K_REG_AMB_LEN_ADDR, &val32))
403                 goto out;
404         data->amb_len = val32;
405 
406         /* Is it big enough? */
407         if (data->amb_len < AMB_CONFIG_SIZE * MAX_AMBS) {
408                 dev_err(&pcidev->dev, "AMB region too small!\n");
409                 goto out;
410         }
411 
412         res = 0;
413 out:
414         pci_dev_put(pcidev);
415         return res;
416 }
417 
418 static int __devinit i5k_channel_probe(u16 *amb_present, unsigned long dev_id)
419 {
420         struct pci_dev *pcidev;
421         u16 val16;
422         int res = -ENODEV;
423 
424         /* Copy the DIMM presence map for these two channels */
425         pcidev = pci_get_device(PCI_VENDOR_ID_INTEL, dev_id, NULL);
426         if (!pcidev)
427                 return -ENODEV;
428 
429         if (pci_read_config_word(pcidev, I5K_REG_CHAN0_PRESENCE_ADDR, &val16))
430                 goto out;
431         amb_present[0] = val16;
432 
433         if (pci_read_config_word(pcidev, I5K_REG_CHAN1_PRESENCE_ADDR, &val16))
434                 goto out;
435         amb_present[1] = val16;
436 
437         res = 0;
438 
439 out:
440         pci_dev_put(pcidev);
441         return res;
442 }
443 
444 static int __devinit i5k_amb_probe(struct platform_device *pdev)
445 {
446         struct i5k_amb_data *data;
447         struct resource *reso;
448         int res = -ENODEV;
449 
450         data = kzalloc(sizeof(*data), GFP_KERNEL);
451         if (!data)
452                 return -ENOMEM;
453 
454         /* Figure out where the AMB registers live */
455         res = i5k_find_amb_registers(data);
456         if (res)
457                 goto err;
458 
459         /* Copy the DIMM presence map for the first two channels */
460         res = i5k_channel_probe(&data->amb_present[0],
461                                 PCI_DEVICE_ID_INTEL_5000_FBD0);
462         if (res)
463                 goto err;
464 
465         /* Copy the DIMM presence map for the optional second two channels */
466         i5k_channel_probe(&data->amb_present[2],
467                           PCI_DEVICE_ID_INTEL_5000_FBD1);
468 
469         /* Set up resource regions */
470         reso = request_mem_region(data->amb_base, data->amb_len, DRVNAME);
471         if (!reso) {
472                 res = -EBUSY;
473                 goto err;
474         }
475 
476         data->amb_mmio = ioremap_nocache(data->amb_base, data->amb_len);
477         if (!data->amb_mmio) {
478                 res = -EBUSY;
479                 goto err_map_failed;
480         }
481 
482         platform_set_drvdata(pdev, data);
483 
484         res = i5k_amb_hwmon_init(pdev);
485         if (res)
486                 goto err_init_failed;
487 
488         return res;
489 
490 err_init_failed:
491         iounmap(data->amb_mmio);
492         platform_set_drvdata(pdev, NULL);
493 err_map_failed:
494         release_mem_region(data->amb_base, data->amb_len);
495 err:
496         kfree(data);
497         return res;
498 }
499 
500 static int __devexit i5k_amb_remove(struct platform_device *pdev)
501 {
502         int i;
503         struct i5k_amb_data *data = platform_get_drvdata(pdev);
504 
505         hwmon_device_unregister(data->hwmon_dev);
506         device_remove_file(&pdev->dev, &dev_attr_name);
507         for (i = 0; i < data->num_attrs; i++)
508                 device_remove_file(&pdev->dev, &data->attrs[i].s_attr.dev_attr);
509         kfree(data->attrs);
510         iounmap(data->amb_mmio);
511         release_mem_region(data->amb_base, data->amb_len);
512         platform_set_drvdata(pdev, NULL);
513         kfree(data);
514         return 0;
515 }
516 
517 static struct platform_driver i5k_amb_driver = {
518         .driver = {
519                 .owner = THIS_MODULE,
520                 .name = DRVNAME,
521         },
522         .probe = i5k_amb_probe,
523         .remove = __devexit_p(i5k_amb_remove),
524 };
525 
526 static int __init i5k_amb_init(void)
527 {
528         int res;
529 
530         res = platform_driver_register(&i5k_amb_driver);
531         if (res)
532                 return res;
533 
534         res = i5k_amb_add();
535         if (res)
536                 platform_driver_unregister(&i5k_amb_driver);
537 
538         return res;
539 }
540 
541 static void __exit i5k_amb_exit(void)
542 {
543         platform_device_unregister(amb_pdev);
544         platform_driver_unregister(&i5k_amb_driver);
545 }
546 
547 MODULE_AUTHOR("Darrick J. Wong <djwong@us.ibm.com>");
548 MODULE_DESCRIPTION("Intel 5000 chipset FB-DIMM AMB temperature sensor");
549 MODULE_LICENSE("GPL");
550 
551 module_init(i5k_amb_init);
552 module_exit(i5k_amb_exit);
553 
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