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 <darrick.wong@oracle.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/hwmon.h>
25#include <linux/hwmon-sysfs.h>
26#include <linux/err.h>
27#include <linux/mutex.h>
28#include <linux/log2.h>
29#include <linux/pci.h>
30#include <linux/platform_device.h>
31#include <linux/slab.h>
32
33#define DRVNAME "i5k_amb"
34
35#define I5K_REG_AMB_BASE_ADDR		0x48
36#define I5K_REG_AMB_LEN_ADDR		0x50
37#define I5K_REG_CHAN0_PRESENCE_ADDR	0x64
38#define I5K_REG_CHAN1_PRESENCE_ADDR	0x66
39
40#define AMB_REG_TEMP_MIN_ADDR		0x80
41#define AMB_REG_TEMP_MID_ADDR		0x81
42#define AMB_REG_TEMP_MAX_ADDR		0x82
43#define AMB_REG_TEMP_STATUS_ADDR	0x84
44#define AMB_REG_TEMP_ADDR		0x85
45
46#define AMB_CONFIG_SIZE			2048
47#define AMB_FUNC_3_OFFSET		768
48
49static unsigned long amb_reg_temp_status(unsigned int amb)
50{
51	return AMB_FUNC_3_OFFSET + AMB_REG_TEMP_STATUS_ADDR +
52	       AMB_CONFIG_SIZE * amb;
53}
54
55static unsigned long amb_reg_temp_min(unsigned int amb)
56{
57	return AMB_FUNC_3_OFFSET + AMB_REG_TEMP_MIN_ADDR +
58	       AMB_CONFIG_SIZE * amb;
59}
60
61static unsigned long amb_reg_temp_mid(unsigned int amb)
62{
63	return AMB_FUNC_3_OFFSET + AMB_REG_TEMP_MID_ADDR +
64	       AMB_CONFIG_SIZE * amb;
65}
66
67static unsigned long amb_reg_temp_max(unsigned int amb)
68{
69	return AMB_FUNC_3_OFFSET + AMB_REG_TEMP_MAX_ADDR +
70	       AMB_CONFIG_SIZE * amb;
71}
72
73static unsigned long amb_reg_temp(unsigned int amb)
74{
75	return AMB_FUNC_3_OFFSET + AMB_REG_TEMP_ADDR +
76	       AMB_CONFIG_SIZE * amb;
77}
78
79#define MAX_MEM_CHANNELS		4
80#define MAX_AMBS_PER_CHANNEL		16
81#define MAX_AMBS			(MAX_MEM_CHANNELS * \
82					 MAX_AMBS_PER_CHANNEL)
83#define CHANNEL_SHIFT			4
84#define DIMM_MASK			0xF
85/*
86 * Ugly hack: For some reason the highest bit is set if there
87 * are _any_ DIMMs in the channel.  Attempting to read from
88 * this "high-order" AMB results in a memory bus error, so
89 * for now we'll just ignore that top bit, even though that
90 * might prevent us from seeing the 16th DIMM in the channel.
91 */
92#define REAL_MAX_AMBS_PER_CHANNEL	15
93#define KNOBS_PER_AMB			6
94
95static unsigned long amb_num_from_reg(unsigned int byte_num, unsigned int bit)
96{
97	return byte_num * MAX_AMBS_PER_CHANNEL + bit;
98}
99
100#define AMB_SYSFS_NAME_LEN		16
101struct i5k_device_attribute {
102	struct sensor_device_attribute s_attr;
103	char name[AMB_SYSFS_NAME_LEN];
104};
105
106struct i5k_amb_data {
107	struct device *hwmon_dev;
108
109	unsigned long amb_base;
110	unsigned long amb_len;
111	u16 amb_present[MAX_MEM_CHANNELS];
112	void __iomem *amb_mmio;
113	struct i5k_device_attribute *attrs;
114	unsigned int num_attrs;
115};
116
117static ssize_t show_name(struct device *dev, struct device_attribute *devattr,
118			 char *buf)
119{
120	return sprintf(buf, "%s\n", DRVNAME);
121}
122
123
124static DEVICE_ATTR(name, S_IRUGO, show_name, NULL);
125
126static struct platform_device *amb_pdev;
127
128static u8 amb_read_byte(struct i5k_amb_data *data, unsigned long offset)
129{
130	return ioread8(data->amb_mmio + offset);
131}
132
133static void amb_write_byte(struct i5k_amb_data *data, unsigned long offset,
134			   u8 val)
135{
136	iowrite8(val, data->amb_mmio + offset);
137}
138
139static ssize_t show_amb_alarm(struct device *dev,
140			     struct device_attribute *devattr,
141			     char *buf)
142{
143	struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
144	struct i5k_amb_data *data = dev_get_drvdata(dev);
145
146	if (!(amb_read_byte(data, amb_reg_temp_status(attr->index)) & 0x20) &&
147	     (amb_read_byte(data, amb_reg_temp_status(attr->index)) & 0x8))
148		return sprintf(buf, "1\n");
149	else
150		return sprintf(buf, "0\n");
151}
152
153static ssize_t store_amb_min(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_min(attr->index), temp);
170	return count;
171}
172
173static ssize_t store_amb_mid(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_mid(attr->index), temp);
190	return count;
191}
192
193static ssize_t store_amb_max(struct device *dev,
194			     struct device_attribute *devattr,
195			     const char *buf,
196			     size_t count)
197{
198	struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
199	struct i5k_amb_data *data = dev_get_drvdata(dev);
200	unsigned long temp;
201	int ret = kstrtoul(buf, 10, &temp);
202	if (ret < 0)
203		return ret;
204
205	temp = temp / 500;
206	if (temp > 255)
207		temp = 255;
208
209	amb_write_byte(data, amb_reg_temp_max(attr->index), temp);
210	return count;
211}
212
213static ssize_t show_amb_min(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_min(attr->index)));
221}
222
223static ssize_t show_amb_mid(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_mid(attr->index)));
231}
232
233static ssize_t show_amb_max(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_max(attr->index)));
241}
242
243static ssize_t show_amb_temp(struct device *dev,
244			     struct device_attribute *devattr,
245			     char *buf)
246{
247	struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
248	struct i5k_amb_data *data = dev_get_drvdata(dev);
249	return sprintf(buf, "%d\n",
250		500 * amb_read_byte(data, amb_reg_temp(attr->index)));
251}
252
253static ssize_t show_label(struct device *dev,
254			  struct device_attribute *devattr,
255			  char *buf)
256{
257	struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
258
259	return sprintf(buf, "Ch. %d DIMM %d\n", attr->index >> CHANNEL_SHIFT,
260		       attr->index & DIMM_MASK);
261}
262
263static int i5k_amb_hwmon_init(struct platform_device *pdev)
264{
265	int i, j, k, d = 0;
266	u16 c;
267	int res = 0;
268	int num_ambs = 0;
269	struct i5k_amb_data *data = platform_get_drvdata(pdev);
270
271	/* Count the number of AMBs found */
272	/* ignore the high-order bit, see "Ugly hack" comment above */
273	for (i = 0; i < MAX_MEM_CHANNELS; i++)
274		num_ambs += hweight16(data->amb_present[i] & 0x7fff);
275
276	/* Set up sysfs stuff */
277	data->attrs = kzalloc(sizeof(*data->attrs) * num_ambs * KNOBS_PER_AMB,
278				GFP_KERNEL);
279	if (!data->attrs)
280		return -ENOMEM;
281	data->num_attrs = 0;
282
283	for (i = 0; i < MAX_MEM_CHANNELS; i++) {
284		c = data->amb_present[i];
285		for (j = 0; j < REAL_MAX_AMBS_PER_CHANNEL; j++, c >>= 1) {
286			struct i5k_device_attribute *iattr;
287
288			k = amb_num_from_reg(i, j);
289			if (!(c & 0x1))
290				continue;
291			d++;
292
293			/* sysfs label */
294			iattr = data->attrs + data->num_attrs;
295			snprintf(iattr->name, AMB_SYSFS_NAME_LEN,
296				 "temp%d_label", d);
297			iattr->s_attr.dev_attr.attr.name = iattr->name;
298			iattr->s_attr.dev_attr.attr.mode = S_IRUGO;
299			iattr->s_attr.dev_attr.show = show_label;
300			iattr->s_attr.index = k;
301			sysfs_attr_init(&iattr->s_attr.dev_attr.attr);
302			res = device_create_file(&pdev->dev,
303						 &iattr->s_attr.dev_attr);
304			if (res)
305				goto exit_remove;
306			data->num_attrs++;
307
308			/* Temperature sysfs knob */
309			iattr = data->attrs + data->num_attrs;
310			snprintf(iattr->name, AMB_SYSFS_NAME_LEN,
311				 "temp%d_input", d);
312			iattr->s_attr.dev_attr.attr.name = iattr->name;
313			iattr->s_attr.dev_attr.attr.mode = S_IRUGO;
314			iattr->s_attr.dev_attr.show = show_amb_temp;
315			iattr->s_attr.index = k;
316			sysfs_attr_init(&iattr->s_attr.dev_attr.attr);
317			res = device_create_file(&pdev->dev,
318						 &iattr->s_attr.dev_attr);
319			if (res)
320				goto exit_remove;
321			data->num_attrs++;
322
323			/* Temperature min sysfs knob */
324			iattr = data->attrs + data->num_attrs;
325			snprintf(iattr->name, AMB_SYSFS_NAME_LEN,
326				 "temp%d_min", d);
327			iattr->s_attr.dev_attr.attr.name = iattr->name;
328			iattr->s_attr.dev_attr.attr.mode = S_IWUSR | S_IRUGO;
329			iattr->s_attr.dev_attr.show = show_amb_min;
330			iattr->s_attr.dev_attr.store = store_amb_min;
331			iattr->s_attr.index = k;
332			sysfs_attr_init(&iattr->s_attr.dev_attr.attr);
333			res = device_create_file(&pdev->dev,
334						 &iattr->s_attr.dev_attr);
335			if (res)
336				goto exit_remove;
337			data->num_attrs++;
338
339			/* Temperature mid sysfs knob */
340			iattr = data->attrs + data->num_attrs;
341			snprintf(iattr->name, AMB_SYSFS_NAME_LEN,
342				 "temp%d_mid", d);
343			iattr->s_attr.dev_attr.attr.name = iattr->name;
344			iattr->s_attr.dev_attr.attr.mode = S_IWUSR | S_IRUGO;
345			iattr->s_attr.dev_attr.show = show_amb_mid;
346			iattr->s_attr.dev_attr.store = store_amb_mid;
347			iattr->s_attr.index = k;
348			sysfs_attr_init(&iattr->s_attr.dev_attr.attr);
349			res = device_create_file(&pdev->dev,
350						 &iattr->s_attr.dev_attr);
351			if (res)
352				goto exit_remove;
353			data->num_attrs++;
354
355			/* Temperature max sysfs knob */
356			iattr = data->attrs + data->num_attrs;
357			snprintf(iattr->name, AMB_SYSFS_NAME_LEN,
358				 "temp%d_max", d);
359			iattr->s_attr.dev_attr.attr.name = iattr->name;
360			iattr->s_attr.dev_attr.attr.mode = S_IWUSR | S_IRUGO;
361			iattr->s_attr.dev_attr.show = show_amb_max;
362			iattr->s_attr.dev_attr.store = store_amb_max;
363			iattr->s_attr.index = k;
364			sysfs_attr_init(&iattr->s_attr.dev_attr.attr);
365			res = device_create_file(&pdev->dev,
366						 &iattr->s_attr.dev_attr);
367			if (res)
368				goto exit_remove;
369			data->num_attrs++;
370
371			/* Temperature alarm sysfs knob */
372			iattr = data->attrs + data->num_attrs;
373			snprintf(iattr->name, AMB_SYSFS_NAME_LEN,
374				 "temp%d_alarm", d);
375			iattr->s_attr.dev_attr.attr.name = iattr->name;
376			iattr->s_attr.dev_attr.attr.mode = S_IRUGO;
377			iattr->s_attr.dev_attr.show = show_amb_alarm;
378			iattr->s_attr.index = k;
379			sysfs_attr_init(&iattr->s_attr.dev_attr.attr);
380			res = device_create_file(&pdev->dev,
381						 &iattr->s_attr.dev_attr);
382			if (res)
383				goto exit_remove;
384			data->num_attrs++;
385		}
386	}
387
388	res = device_create_file(&pdev->dev, &dev_attr_name);
389	if (res)
390		goto exit_remove;
391
392	data->hwmon_dev = hwmon_device_register(&pdev->dev);
393	if (IS_ERR(data->hwmon_dev)) {
394		res = PTR_ERR(data->hwmon_dev);
395		goto exit_remove;
396	}
397
398	return res;
399
400exit_remove:
401	device_remove_file(&pdev->dev, &dev_attr_name);
402	for (i = 0; i < data->num_attrs; i++)
403		device_remove_file(&pdev->dev, &data->attrs[i].s_attr.dev_attr);
404	kfree(data->attrs);
405
406	return res;
407}
408
409static int i5k_amb_add(void)
410{
411	int res = -ENODEV;
412
413	/* only ever going to be one of these */
414	amb_pdev = platform_device_alloc(DRVNAME, 0);
415	if (!amb_pdev)
416		return -ENOMEM;
417
418	res = platform_device_add(amb_pdev);
419	if (res)
420		goto err;
421	return 0;
422
423err:
424	platform_device_put(amb_pdev);
425	return res;
426}
427
428static int i5k_find_amb_registers(struct i5k_amb_data *data,
429					    unsigned long devid)
430{
431	struct pci_dev *pcidev;
432	u32 val32;
433	int res = -ENODEV;
434
435	/* Find AMB register memory space */
436	pcidev = pci_get_device(PCI_VENDOR_ID_INTEL,
437				devid,
438				NULL);
439	if (!pcidev)
440		return -ENODEV;
441
442	if (pci_read_config_dword(pcidev, I5K_REG_AMB_BASE_ADDR, &val32))
443		goto out;
444	data->amb_base = val32;
445
446	if (pci_read_config_dword(pcidev, I5K_REG_AMB_LEN_ADDR, &val32))
447		goto out;
448	data->amb_len = val32;
449
450	/* Is it big enough? */
451	if (data->amb_len < AMB_CONFIG_SIZE * MAX_AMBS) {
452		dev_err(&pcidev->dev, "AMB region too small!\n");
453		goto out;
454	}
455
456	res = 0;
457out:
458	pci_dev_put(pcidev);
459	return res;
460}
461
462static int i5k_channel_probe(u16 *amb_present, unsigned long dev_id)
463{
464	struct pci_dev *pcidev;
465	u16 val16;
466	int res = -ENODEV;
467
468	/* Copy the DIMM presence map for these two channels */
469	pcidev = pci_get_device(PCI_VENDOR_ID_INTEL, dev_id, NULL);
470	if (!pcidev)
471		return -ENODEV;
472
473	if (pci_read_config_word(pcidev, I5K_REG_CHAN0_PRESENCE_ADDR, &val16))
474		goto out;
475	amb_present[0] = val16;
476
477	if (pci_read_config_word(pcidev, I5K_REG_CHAN1_PRESENCE_ADDR, &val16))
478		goto out;
479	amb_present[1] = val16;
480
481	res = 0;
482
483out:
484	pci_dev_put(pcidev);
485	return res;
486}
487
488static struct {
489	unsigned long err;
490	unsigned long fbd0;
491} chipset_ids[]  = {
492	{ PCI_DEVICE_ID_INTEL_5000_ERR, PCI_DEVICE_ID_INTEL_5000_FBD0 },
493	{ PCI_DEVICE_ID_INTEL_5400_ERR, PCI_DEVICE_ID_INTEL_5400_FBD0 },
494	{ 0, 0 }
495};
496
497#ifdef MODULE
498static struct pci_device_id i5k_amb_ids[] = {
499	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_5000_ERR) },
500	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_5400_ERR) },
501	{ 0, }
502};
503MODULE_DEVICE_TABLE(pci, i5k_amb_ids);
504#endif
505
506static int i5k_amb_probe(struct platform_device *pdev)
507{
508	struct i5k_amb_data *data;
509	struct resource *reso;
510	int i, res;
511
512	data = kzalloc(sizeof(*data), GFP_KERNEL);
513	if (!data)
514		return -ENOMEM;
515
516	/* Figure out where the AMB registers live */
517	i = 0;
518	do {
519		res = i5k_find_amb_registers(data, chipset_ids[i].err);
520		if (res == 0)
521			break;
522		i++;
523	} while (chipset_ids[i].err);
524
525	if (res)
526		goto err;
527
528	/* Copy the DIMM presence map for the first two channels */
529	res = i5k_channel_probe(&data->amb_present[0], chipset_ids[i].fbd0);
530	if (res)
531		goto err;
532
533	/* Copy the DIMM presence map for the optional second two channels */
534	i5k_channel_probe(&data->amb_present[2], chipset_ids[i].fbd0 + 1);
535
536	/* Set up resource regions */
537	reso = request_mem_region(data->amb_base, data->amb_len, DRVNAME);
538	if (!reso) {
539		res = -EBUSY;
540		goto err;
541	}
542
543	data->amb_mmio = ioremap_nocache(data->amb_base, data->amb_len);
544	if (!data->amb_mmio) {
545		res = -EBUSY;
546		goto err_map_failed;
547	}
548
549	platform_set_drvdata(pdev, data);
550
551	res = i5k_amb_hwmon_init(pdev);
552	if (res)
553		goto err_init_failed;
554
555	return res;
556
557err_init_failed:
558	iounmap(data->amb_mmio);
559err_map_failed:
560	release_mem_region(data->amb_base, data->amb_len);
561err:
562	kfree(data);
563	return res;
564}
565
566static int i5k_amb_remove(struct platform_device *pdev)
567{
568	int i;
569	struct i5k_amb_data *data = platform_get_drvdata(pdev);
570
571	hwmon_device_unregister(data->hwmon_dev);
572	device_remove_file(&pdev->dev, &dev_attr_name);
573	for (i = 0; i < data->num_attrs; i++)
574		device_remove_file(&pdev->dev, &data->attrs[i].s_attr.dev_attr);
575	kfree(data->attrs);
576	iounmap(data->amb_mmio);
577	release_mem_region(data->amb_base, data->amb_len);
578	kfree(data);
579	return 0;
580}
581
582static struct platform_driver i5k_amb_driver = {
583	.driver = {
584		.name = DRVNAME,
585	},
586	.probe = i5k_amb_probe,
587	.remove = i5k_amb_remove,
588};
589
590static int __init i5k_amb_init(void)
591{
592	int res;
593
594	res = platform_driver_register(&i5k_amb_driver);
595	if (res)
596		return res;
597
598	res = i5k_amb_add();
599	if (res)
600		platform_driver_unregister(&i5k_amb_driver);
601
602	return res;
603}
604
605static void __exit i5k_amb_exit(void)
606{
607	platform_device_unregister(amb_pdev);
608	platform_driver_unregister(&i5k_amb_driver);
609}
610
611MODULE_AUTHOR("Darrick J. Wong <darrick.wong@oracle.com>");
612MODULE_DESCRIPTION("Intel 5000 chipset FB-DIMM AMB temperature sensor");
613MODULE_LICENSE("GPL");
614
615module_init(i5k_amb_init);
616module_exit(i5k_amb_exit);
617