xref: /linux/drivers/hwmon/i5k_amb.c (revision 60e13231561b3a4c5269bfa1ef6c0569ad6f28ec)
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 #include <linux/slab.h>
34 
35 #define DRVNAME "i5k_amb"
36 
37 #define I5K_REG_AMB_BASE_ADDR		0x48
38 #define I5K_REG_AMB_LEN_ADDR		0x50
39 #define I5K_REG_CHAN0_PRESENCE_ADDR	0x64
40 #define I5K_REG_CHAN1_PRESENCE_ADDR	0x66
41 
42 #define AMB_REG_TEMP_MIN_ADDR		0x80
43 #define AMB_REG_TEMP_MID_ADDR		0x81
44 #define AMB_REG_TEMP_MAX_ADDR		0x82
45 #define AMB_REG_TEMP_STATUS_ADDR	0x84
46 #define AMB_REG_TEMP_ADDR		0x85
47 
48 #define AMB_CONFIG_SIZE			2048
49 #define AMB_FUNC_3_OFFSET		768
50 
51 static unsigned long amb_reg_temp_status(unsigned int amb)
52 {
53 	return AMB_FUNC_3_OFFSET + AMB_REG_TEMP_STATUS_ADDR +
54 	       AMB_CONFIG_SIZE * amb;
55 }
56 
57 static unsigned long amb_reg_temp_min(unsigned int amb)
58 {
59 	return AMB_FUNC_3_OFFSET + AMB_REG_TEMP_MIN_ADDR +
60 	       AMB_CONFIG_SIZE * amb;
61 }
62 
63 static unsigned long amb_reg_temp_mid(unsigned int amb)
64 {
65 	return AMB_FUNC_3_OFFSET + AMB_REG_TEMP_MID_ADDR +
66 	       AMB_CONFIG_SIZE * amb;
67 }
68 
69 static unsigned long amb_reg_temp_max(unsigned int amb)
70 {
71 	return AMB_FUNC_3_OFFSET + AMB_REG_TEMP_MAX_ADDR +
72 	       AMB_CONFIG_SIZE * amb;
73 }
74 
75 static unsigned long amb_reg_temp(unsigned int amb)
76 {
77 	return AMB_FUNC_3_OFFSET + AMB_REG_TEMP_ADDR +
78 	       AMB_CONFIG_SIZE * amb;
79 }
80 
81 #define MAX_MEM_CHANNELS		4
82 #define MAX_AMBS_PER_CHANNEL		16
83 #define MAX_AMBS			(MAX_MEM_CHANNELS * \
84 					 MAX_AMBS_PER_CHANNEL)
85 #define CHANNEL_SHIFT			4
86 #define DIMM_MASK			0xF
87 /*
88  * Ugly hack: For some reason the highest bit is set if there
89  * are _any_ DIMMs in the channel.  Attempting to read from
90  * this "high-order" AMB results in a memory bus error, so
91  * for now we'll just ignore that top bit, even though that
92  * might prevent us from seeing the 16th DIMM in the channel.
93  */
94 #define REAL_MAX_AMBS_PER_CHANNEL	15
95 #define KNOBS_PER_AMB			6
96 
97 static unsigned long amb_num_from_reg(unsigned int byte_num, unsigned int bit)
98 {
99 	return byte_num * MAX_AMBS_PER_CHANNEL + bit;
100 }
101 
102 #define AMB_SYSFS_NAME_LEN		16
103 struct i5k_device_attribute {
104 	struct sensor_device_attribute s_attr;
105 	char name[AMB_SYSFS_NAME_LEN];
106 };
107 
108 struct i5k_amb_data {
109 	struct device *hwmon_dev;
110 
111 	unsigned long amb_base;
112 	unsigned long amb_len;
113 	u16 amb_present[MAX_MEM_CHANNELS];
114 	void __iomem *amb_mmio;
115 	struct i5k_device_attribute *attrs;
116 	unsigned int num_attrs;
117 };
118 
119 static ssize_t show_name(struct device *dev, struct device_attribute *devattr,
120 			 char *buf)
121 {
122 	return sprintf(buf, "%s\n", DRVNAME);
123 }
124 
125 
126 static DEVICE_ATTR(name, S_IRUGO, show_name, NULL);
127 
128 static struct platform_device *amb_pdev;
129 
130 static u8 amb_read_byte(struct i5k_amb_data *data, unsigned long offset)
131 {
132 	return ioread8(data->amb_mmio + offset);
133 }
134 
135 static void amb_write_byte(struct i5k_amb_data *data, unsigned long offset,
136 			   u8 val)
137 {
138 	iowrite8(val, data->amb_mmio + offset);
139 }
140 
141 static ssize_t show_amb_alarm(struct device *dev,
142 			     struct device_attribute *devattr,
143 			     char *buf)
144 {
145 	struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
146 	struct i5k_amb_data *data = dev_get_drvdata(dev);
147 
148 	if (!(amb_read_byte(data, amb_reg_temp_status(attr->index)) & 0x20) &&
149 	     (amb_read_byte(data, amb_reg_temp_status(attr->index)) & 0x8))
150 		return sprintf(buf, "1\n");
151 	else
152 		return sprintf(buf, "0\n");
153 }
154 
155 static ssize_t store_amb_min(struct device *dev,
156 			     struct device_attribute *devattr,
157 			     const char *buf,
158 			     size_t count)
159 {
160 	struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
161 	struct i5k_amb_data *data = dev_get_drvdata(dev);
162 	unsigned long temp = simple_strtoul(buf, NULL, 10) / 500;
163 
164 	if (temp > 255)
165 		temp = 255;
166 
167 	amb_write_byte(data, amb_reg_temp_min(attr->index), temp);
168 	return count;
169 }
170 
171 static ssize_t store_amb_mid(struct device *dev,
172 			     struct device_attribute *devattr,
173 			     const char *buf,
174 			     size_t count)
175 {
176 	struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
177 	struct i5k_amb_data *data = dev_get_drvdata(dev);
178 	unsigned long temp = simple_strtoul(buf, NULL, 10) / 500;
179 
180 	if (temp > 255)
181 		temp = 255;
182 
183 	amb_write_byte(data, amb_reg_temp_mid(attr->index), temp);
184 	return count;
185 }
186 
187 static ssize_t store_amb_max(struct device *dev,
188 			     struct device_attribute *devattr,
189 			     const char *buf,
190 			     size_t count)
191 {
192 	struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
193 	struct i5k_amb_data *data = dev_get_drvdata(dev);
194 	unsigned long temp = simple_strtoul(buf, NULL, 10) / 500;
195 
196 	if (temp > 255)
197 		temp = 255;
198 
199 	amb_write_byte(data, amb_reg_temp_max(attr->index), temp);
200 	return count;
201 }
202 
203 static ssize_t show_amb_min(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_min(attr->index)));
211 }
212 
213 static ssize_t show_amb_mid(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_mid(attr->index)));
221 }
222 
223 static ssize_t show_amb_max(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_max(attr->index)));
231 }
232 
233 static ssize_t show_amb_temp(struct device *dev,
234 			     struct device_attribute *devattr,
235 			     char *buf)
236 {
237 	struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
238 	struct i5k_amb_data *data = dev_get_drvdata(dev);
239 	return sprintf(buf, "%d\n",
240 		500 * amb_read_byte(data, amb_reg_temp(attr->index)));
241 }
242 
243 static ssize_t show_label(struct device *dev,
244 			  struct device_attribute *devattr,
245 			  char *buf)
246 {
247 	struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
248 
249 	return sprintf(buf, "Ch. %d DIMM %d\n", attr->index >> CHANNEL_SHIFT,
250 		       attr->index & DIMM_MASK);
251 }
252 
253 static int __devinit i5k_amb_hwmon_init(struct platform_device *pdev)
254 {
255 	int i, j, k, d = 0;
256 	u16 c;
257 	int res = 0;
258 	int num_ambs = 0;
259 	struct i5k_amb_data *data = platform_get_drvdata(pdev);
260 
261 	/* Count the number of AMBs found */
262 	/* ignore the high-order bit, see "Ugly hack" comment above */
263 	for (i = 0; i < MAX_MEM_CHANNELS; i++)
264 		num_ambs += hweight16(data->amb_present[i] & 0x7fff);
265 
266 	/* Set up sysfs stuff */
267 	data->attrs = kzalloc(sizeof(*data->attrs) * num_ambs * KNOBS_PER_AMB,
268 				GFP_KERNEL);
269 	if (!data->attrs)
270 		return -ENOMEM;
271 	data->num_attrs = 0;
272 
273 	for (i = 0; i < MAX_MEM_CHANNELS; i++) {
274 		c = data->amb_present[i];
275 		for (j = 0; j < REAL_MAX_AMBS_PER_CHANNEL; j++, c >>= 1) {
276 			struct i5k_device_attribute *iattr;
277 
278 			k = amb_num_from_reg(i, j);
279 			if (!(c & 0x1))
280 				continue;
281 			d++;
282 
283 			/* sysfs label */
284 			iattr = data->attrs + data->num_attrs;
285 			snprintf(iattr->name, AMB_SYSFS_NAME_LEN,
286 				 "temp%d_label", d);
287 			iattr->s_attr.dev_attr.attr.name = iattr->name;
288 			iattr->s_attr.dev_attr.attr.mode = S_IRUGO;
289 			iattr->s_attr.dev_attr.show = show_label;
290 			iattr->s_attr.index = k;
291 			sysfs_attr_init(&iattr->s_attr.dev_attr.attr);
292 			res = device_create_file(&pdev->dev,
293 						 &iattr->s_attr.dev_attr);
294 			if (res)
295 				goto exit_remove;
296 			data->num_attrs++;
297 
298 			/* Temperature sysfs knob */
299 			iattr = data->attrs + data->num_attrs;
300 			snprintf(iattr->name, AMB_SYSFS_NAME_LEN,
301 				 "temp%d_input", d);
302 			iattr->s_attr.dev_attr.attr.name = iattr->name;
303 			iattr->s_attr.dev_attr.attr.mode = S_IRUGO;
304 			iattr->s_attr.dev_attr.show = show_amb_temp;
305 			iattr->s_attr.index = k;
306 			sysfs_attr_init(&iattr->s_attr.dev_attr.attr);
307 			res = device_create_file(&pdev->dev,
308 						 &iattr->s_attr.dev_attr);
309 			if (res)
310 				goto exit_remove;
311 			data->num_attrs++;
312 
313 			/* Temperature min sysfs knob */
314 			iattr = data->attrs + data->num_attrs;
315 			snprintf(iattr->name, AMB_SYSFS_NAME_LEN,
316 				 "temp%d_min", d);
317 			iattr->s_attr.dev_attr.attr.name = iattr->name;
318 			iattr->s_attr.dev_attr.attr.mode = S_IWUSR | S_IRUGO;
319 			iattr->s_attr.dev_attr.show = show_amb_min;
320 			iattr->s_attr.dev_attr.store = store_amb_min;
321 			iattr->s_attr.index = k;
322 			sysfs_attr_init(&iattr->s_attr.dev_attr.attr);
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 mid sysfs knob */
330 			iattr = data->attrs + data->num_attrs;
331 			snprintf(iattr->name, AMB_SYSFS_NAME_LEN,
332 				 "temp%d_mid", d);
333 			iattr->s_attr.dev_attr.attr.name = iattr->name;
334 			iattr->s_attr.dev_attr.attr.mode = S_IWUSR | S_IRUGO;
335 			iattr->s_attr.dev_attr.show = show_amb_mid;
336 			iattr->s_attr.dev_attr.store = store_amb_mid;
337 			iattr->s_attr.index = k;
338 			sysfs_attr_init(&iattr->s_attr.dev_attr.attr);
339 			res = device_create_file(&pdev->dev,
340 						 &iattr->s_attr.dev_attr);
341 			if (res)
342 				goto exit_remove;
343 			data->num_attrs++;
344 
345 			/* Temperature max sysfs knob */
346 			iattr = data->attrs + data->num_attrs;
347 			snprintf(iattr->name, AMB_SYSFS_NAME_LEN,
348 				 "temp%d_max", d);
349 			iattr->s_attr.dev_attr.attr.name = iattr->name;
350 			iattr->s_attr.dev_attr.attr.mode = S_IWUSR | S_IRUGO;
351 			iattr->s_attr.dev_attr.show = show_amb_max;
352 			iattr->s_attr.dev_attr.store = store_amb_max;
353 			iattr->s_attr.index = k;
354 			sysfs_attr_init(&iattr->s_attr.dev_attr.attr);
355 			res = device_create_file(&pdev->dev,
356 						 &iattr->s_attr.dev_attr);
357 			if (res)
358 				goto exit_remove;
359 			data->num_attrs++;
360 
361 			/* Temperature alarm sysfs knob */
362 			iattr = data->attrs + data->num_attrs;
363 			snprintf(iattr->name, AMB_SYSFS_NAME_LEN,
364 				 "temp%d_alarm", d);
365 			iattr->s_attr.dev_attr.attr.name = iattr->name;
366 			iattr->s_attr.dev_attr.attr.mode = S_IRUGO;
367 			iattr->s_attr.dev_attr.show = show_amb_alarm;
368 			iattr->s_attr.index = k;
369 			sysfs_attr_init(&iattr->s_attr.dev_attr.attr);
370 			res = device_create_file(&pdev->dev,
371 						 &iattr->s_attr.dev_attr);
372 			if (res)
373 				goto exit_remove;
374 			data->num_attrs++;
375 		}
376 	}
377 
378 	res = device_create_file(&pdev->dev, &dev_attr_name);
379 	if (res)
380 		goto exit_remove;
381 
382 	data->hwmon_dev = hwmon_device_register(&pdev->dev);
383 	if (IS_ERR(data->hwmon_dev)) {
384 		res = PTR_ERR(data->hwmon_dev);
385 		goto exit_remove;
386 	}
387 
388 	return res;
389 
390 exit_remove:
391 	device_remove_file(&pdev->dev, &dev_attr_name);
392 	for (i = 0; i < data->num_attrs; i++)
393 		device_remove_file(&pdev->dev, &data->attrs[i].s_attr.dev_attr);
394 	kfree(data->attrs);
395 
396 	return res;
397 }
398 
399 static int __devinit i5k_amb_add(void)
400 {
401 	int res = -ENODEV;
402 
403 	/* only ever going to be one of these */
404 	amb_pdev = platform_device_alloc(DRVNAME, 0);
405 	if (!amb_pdev)
406 		return -ENOMEM;
407 
408 	res = platform_device_add(amb_pdev);
409 	if (res)
410 		goto err;
411 	return 0;
412 
413 err:
414 	platform_device_put(amb_pdev);
415 	return res;
416 }
417 
418 static int __devinit i5k_find_amb_registers(struct i5k_amb_data *data,
419 					    unsigned long devid)
420 {
421 	struct pci_dev *pcidev;
422 	u32 val32;
423 	int res = -ENODEV;
424 
425 	/* Find AMB register memory space */
426 	pcidev = pci_get_device(PCI_VENDOR_ID_INTEL,
427 				devid,
428 				NULL);
429 	if (!pcidev)
430 		return -ENODEV;
431 
432 	if (pci_read_config_dword(pcidev, I5K_REG_AMB_BASE_ADDR, &val32))
433 		goto out;
434 	data->amb_base = val32;
435 
436 	if (pci_read_config_dword(pcidev, I5K_REG_AMB_LEN_ADDR, &val32))
437 		goto out;
438 	data->amb_len = val32;
439 
440 	/* Is it big enough? */
441 	if (data->amb_len < AMB_CONFIG_SIZE * MAX_AMBS) {
442 		dev_err(&pcidev->dev, "AMB region too small!\n");
443 		goto out;
444 	}
445 
446 	res = 0;
447 out:
448 	pci_dev_put(pcidev);
449 	return res;
450 }
451 
452 static int __devinit i5k_channel_probe(u16 *amb_present, unsigned long dev_id)
453 {
454 	struct pci_dev *pcidev;
455 	u16 val16;
456 	int res = -ENODEV;
457 
458 	/* Copy the DIMM presence map for these two channels */
459 	pcidev = pci_get_device(PCI_VENDOR_ID_INTEL, dev_id, NULL);
460 	if (!pcidev)
461 		return -ENODEV;
462 
463 	if (pci_read_config_word(pcidev, I5K_REG_CHAN0_PRESENCE_ADDR, &val16))
464 		goto out;
465 	amb_present[0] = val16;
466 
467 	if (pci_read_config_word(pcidev, I5K_REG_CHAN1_PRESENCE_ADDR, &val16))
468 		goto out;
469 	amb_present[1] = val16;
470 
471 	res = 0;
472 
473 out:
474 	pci_dev_put(pcidev);
475 	return res;
476 }
477 
478 static struct {
479 	unsigned long err;
480 	unsigned long fbd0;
481 } chipset_ids[] __devinitdata  = {
482 	{ PCI_DEVICE_ID_INTEL_5000_ERR, PCI_DEVICE_ID_INTEL_5000_FBD0 },
483 	{ PCI_DEVICE_ID_INTEL_5400_ERR, PCI_DEVICE_ID_INTEL_5400_FBD0 },
484 	{ 0, 0 }
485 };
486 
487 #ifdef MODULE
488 static struct pci_device_id i5k_amb_ids[] __devinitdata = {
489 	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_5000_ERR) },
490 	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_5400_ERR) },
491 	{ 0, }
492 };
493 MODULE_DEVICE_TABLE(pci, i5k_amb_ids);
494 #endif
495 
496 static int __devinit i5k_amb_probe(struct platform_device *pdev)
497 {
498 	struct i5k_amb_data *data;
499 	struct resource *reso;
500 	int i, res;
501 
502 	data = kzalloc(sizeof(*data), GFP_KERNEL);
503 	if (!data)
504 		return -ENOMEM;
505 
506 	/* Figure out where the AMB registers live */
507 	i = 0;
508 	do {
509 		res = i5k_find_amb_registers(data, chipset_ids[i].err);
510 		if (res == 0)
511 			break;
512 		i++;
513 	} while (chipset_ids[i].err);
514 
515 	if (res)
516 		goto err;
517 
518 	/* Copy the DIMM presence map for the first two channels */
519 	res = i5k_channel_probe(&data->amb_present[0], chipset_ids[i].fbd0);
520 	if (res)
521 		goto err;
522 
523 	/* Copy the DIMM presence map for the optional second two channels */
524 	i5k_channel_probe(&data->amb_present[2], chipset_ids[i].fbd0 + 1);
525 
526 	/* Set up resource regions */
527 	reso = request_mem_region(data->amb_base, data->amb_len, DRVNAME);
528 	if (!reso) {
529 		res = -EBUSY;
530 		goto err;
531 	}
532 
533 	data->amb_mmio = ioremap_nocache(data->amb_base, data->amb_len);
534 	if (!data->amb_mmio) {
535 		res = -EBUSY;
536 		goto err_map_failed;
537 	}
538 
539 	platform_set_drvdata(pdev, data);
540 
541 	res = i5k_amb_hwmon_init(pdev);
542 	if (res)
543 		goto err_init_failed;
544 
545 	return res;
546 
547 err_init_failed:
548 	iounmap(data->amb_mmio);
549 	platform_set_drvdata(pdev, NULL);
550 err_map_failed:
551 	release_mem_region(data->amb_base, data->amb_len);
552 err:
553 	kfree(data);
554 	return res;
555 }
556 
557 static int __devexit i5k_amb_remove(struct platform_device *pdev)
558 {
559 	int i;
560 	struct i5k_amb_data *data = platform_get_drvdata(pdev);
561 
562 	hwmon_device_unregister(data->hwmon_dev);
563 	device_remove_file(&pdev->dev, &dev_attr_name);
564 	for (i = 0; i < data->num_attrs; i++)
565 		device_remove_file(&pdev->dev, &data->attrs[i].s_attr.dev_attr);
566 	kfree(data->attrs);
567 	iounmap(data->amb_mmio);
568 	release_mem_region(data->amb_base, data->amb_len);
569 	platform_set_drvdata(pdev, NULL);
570 	kfree(data);
571 	return 0;
572 }
573 
574 static struct platform_driver i5k_amb_driver = {
575 	.driver = {
576 		.owner = THIS_MODULE,
577 		.name = DRVNAME,
578 	},
579 	.probe = i5k_amb_probe,
580 	.remove = __devexit_p(i5k_amb_remove),
581 };
582 
583 static int __init i5k_amb_init(void)
584 {
585 	int res;
586 
587 	res = platform_driver_register(&i5k_amb_driver);
588 	if (res)
589 		return res;
590 
591 	res = i5k_amb_add();
592 	if (res)
593 		platform_driver_unregister(&i5k_amb_driver);
594 
595 	return res;
596 }
597 
598 static void __exit i5k_amb_exit(void)
599 {
600 	platform_device_unregister(amb_pdev);
601 	platform_driver_unregister(&i5k_amb_driver);
602 }
603 
604 MODULE_AUTHOR("Darrick J. Wong <djwong@us.ibm.com>");
605 MODULE_DESCRIPTION("Intel 5000 chipset FB-DIMM AMB temperature sensor");
606 MODULE_LICENSE("GPL");
607 
608 module_init(i5k_amb_init);
609 module_exit(i5k_amb_exit);
610