xref: /openbmc/linux/drivers/hwmon/k8temp.c (revision ab73b751)
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/delay.h>
26 #include <linux/init.h>
27 #include <linux/slab.h>
28 #include <linux/jiffies.h>
29 #include <linux/pci.h>
30 #include <linux/hwmon.h>
31 #include <linux/hwmon-sysfs.h>
32 #include <linux/err.h>
33 #include <linux/mutex.h>
34 #include <asm/processor.h>
35 
36 #define TEMP_FROM_REG(val)	(((((val) >> 16) & 0xff) - 49) * 1000)
37 #define REG_TEMP	0xe4
38 #define SEL_PLACE	0x40
39 #define SEL_CORE	0x04
40 
41 struct k8temp_data {
42 	struct device *hwmon_dev;
43 	struct mutex update_lock;
44 	const char *name;
45 	char valid;		/* zero until following fields are valid */
46 	unsigned long last_updated;	/* in jiffies */
47 
48 	/* registers values */
49 	u8 sensorsp;		/* sensor presence bits - SEL_CORE, SEL_PLACE */
50 	u32 temp[2][2];		/* core, place */
51 	u8 swap_core_select;    /* meaning of SEL_CORE is inverted */
52 	u32 temp_offset;
53 };
54 
55 static struct k8temp_data *k8temp_update_device(struct device *dev)
56 {
57 	struct k8temp_data *data = dev_get_drvdata(dev);
58 	struct pci_dev *pdev = to_pci_dev(dev);
59 	u8 tmp;
60 
61 	mutex_lock(&data->update_lock);
62 
63 	if (!data->valid
64 	    || time_after(jiffies, data->last_updated + HZ)) {
65 		pci_read_config_byte(pdev, REG_TEMP, &tmp);
66 		tmp &= ~(SEL_PLACE | SEL_CORE);	/* Select sensor 0, core0 */
67 		pci_write_config_byte(pdev, REG_TEMP, tmp);
68 		pci_read_config_dword(pdev, REG_TEMP, &data->temp[0][0]);
69 
70 		if (data->sensorsp & SEL_PLACE) {
71 			tmp |= SEL_PLACE;	/* Select sensor 1, core0 */
72 			pci_write_config_byte(pdev, REG_TEMP, tmp);
73 			pci_read_config_dword(pdev, REG_TEMP,
74 					      &data->temp[0][1]);
75 		}
76 
77 		if (data->sensorsp & SEL_CORE) {
78 			tmp &= ~SEL_PLACE;	/* Select sensor 0, core1 */
79 			tmp |= SEL_CORE;
80 			pci_write_config_byte(pdev, REG_TEMP, tmp);
81 			pci_read_config_dword(pdev, REG_TEMP,
82 					      &data->temp[1][0]);
83 
84 			if (data->sensorsp & SEL_PLACE) {
85 				tmp |= SEL_PLACE; /* Select sensor 1, core1 */
86 				pci_write_config_byte(pdev, REG_TEMP, tmp);
87 				pci_read_config_dword(pdev, REG_TEMP,
88 						      &data->temp[1][1]);
89 			}
90 		}
91 
92 		data->last_updated = jiffies;
93 		data->valid = 1;
94 	}
95 
96 	mutex_unlock(&data->update_lock);
97 	return data;
98 }
99 
100 /*
101  * Sysfs stuff
102  */
103 
104 static ssize_t show_name(struct device *dev, struct device_attribute
105 			 *devattr, char *buf)
106 {
107 	struct k8temp_data *data = dev_get_drvdata(dev);
108 
109 	return sprintf(buf, "%s\n", data->name);
110 }
111 
112 
113 static ssize_t show_temp(struct device *dev,
114 			 struct device_attribute *devattr, char *buf)
115 {
116 	struct sensor_device_attribute_2 *attr =
117 	    to_sensor_dev_attr_2(devattr);
118 	int core = attr->nr;
119 	int place = attr->index;
120 	int temp;
121 	struct k8temp_data *data = k8temp_update_device(dev);
122 
123 	if (data->swap_core_select && (data->sensorsp & SEL_CORE))
124 		core = core ? 0 : 1;
125 
126 	temp = TEMP_FROM_REG(data->temp[core][place]) + data->temp_offset;
127 
128 	return sprintf(buf, "%d\n", temp);
129 }
130 
131 /* core, place */
132 
133 static SENSOR_DEVICE_ATTR_2(temp1_input, S_IRUGO, show_temp, NULL, 0, 0);
134 static SENSOR_DEVICE_ATTR_2(temp2_input, S_IRUGO, show_temp, NULL, 0, 1);
135 static SENSOR_DEVICE_ATTR_2(temp3_input, S_IRUGO, show_temp, NULL, 1, 0);
136 static SENSOR_DEVICE_ATTR_2(temp4_input, S_IRUGO, show_temp, NULL, 1, 1);
137 static DEVICE_ATTR(name, S_IRUGO, show_name, NULL);
138 
139 static DEFINE_PCI_DEVICE_TABLE(k8temp_ids) = {
140 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_K8_NB_MISC) },
141 	{ 0 },
142 };
143 
144 MODULE_DEVICE_TABLE(pci, k8temp_ids);
145 
146 static int __devinit is_rev_g_desktop(u8 model)
147 {
148 	u32 brandidx;
149 
150 	if (model < 0x69)
151 		return 0;
152 
153 	if (model == 0xc1 || model == 0x6c || model == 0x7c)
154 		return 0;
155 
156 	/*
157 	 * Differentiate between AM2 and ASB1.
158 	 * See "Constructing the processor Name String" in "Revision
159 	 * Guide for AMD NPT Family 0Fh Processors" (33610).
160 	 */
161 	brandidx = cpuid_ebx(0x80000001);
162 	brandidx = (brandidx >> 9) & 0x1f;
163 
164 	/* Single core */
165 	if ((model == 0x6f || model == 0x7f) &&
166 	    (brandidx == 0x7 || brandidx == 0x9 || brandidx == 0xc))
167 		return 0;
168 
169 	/* Dual core */
170 	if (model == 0x6b &&
171 	    (brandidx == 0xb || brandidx == 0xc))
172 		return 0;
173 
174 	return 1;
175 }
176 
177 static int __devinit k8temp_probe(struct pci_dev *pdev,
178 				  const struct pci_device_id *id)
179 {
180 	int err;
181 	u8 scfg;
182 	u32 temp;
183 	u8 model, stepping;
184 	struct k8temp_data *data;
185 
186 	data = kzalloc(sizeof(struct k8temp_data), GFP_KERNEL);
187 	if (!data) {
188 		err = -ENOMEM;
189 		goto exit;
190 	}
191 
192 	model = boot_cpu_data.x86_model;
193 	stepping = boot_cpu_data.x86_mask;
194 
195 	/* feature available since SH-C0, exclude older revisions */
196 	if (((model == 4) && (stepping == 0)) ||
197 	    ((model == 5) && (stepping <= 1))) {
198 		err = -ENODEV;
199 		goto exit_free;
200 	}
201 
202 	/*
203 	 * AMD NPT family 0fh, i.e. RevF and RevG:
204 	 * meaning of SEL_CORE bit is inverted
205 	 */
206 	if (model >= 0x40) {
207 		data->swap_core_select = 1;
208 		dev_warn(&pdev->dev, "Temperature readouts might be wrong - "
209 			 "check erratum #141\n");
210 	}
211 
212 	/*
213 	 * RevG desktop CPUs (i.e. no socket S1G1 or ASB1 parts) need
214 	 * additional offset, otherwise reported temperature is below
215 	 * ambient temperature
216 	 */
217 	if (is_rev_g_desktop(model))
218 		data->temp_offset = 21000;
219 
220 	pci_read_config_byte(pdev, REG_TEMP, &scfg);
221 	scfg &= ~(SEL_PLACE | SEL_CORE);	/* Select sensor 0, core0 */
222 	pci_write_config_byte(pdev, REG_TEMP, scfg);
223 	pci_read_config_byte(pdev, REG_TEMP, &scfg);
224 
225 	if (scfg & (SEL_PLACE | SEL_CORE)) {
226 		dev_err(&pdev->dev, "Configuration bit(s) stuck at 1!\n");
227 		err = -ENODEV;
228 		goto exit_free;
229 	}
230 
231 	scfg |= (SEL_PLACE | SEL_CORE);
232 	pci_write_config_byte(pdev, REG_TEMP, scfg);
233 
234 	/* now we know if we can change core and/or sensor */
235 	pci_read_config_byte(pdev, REG_TEMP, &data->sensorsp);
236 
237 	if (data->sensorsp & SEL_PLACE) {
238 		scfg &= ~SEL_CORE;	/* Select sensor 1, core0 */
239 		pci_write_config_byte(pdev, REG_TEMP, scfg);
240 		pci_read_config_dword(pdev, REG_TEMP, &temp);
241 		scfg |= SEL_CORE;	/* prepare for next selection */
242 		if (!((temp >> 16) & 0xff)) /* if temp is 0 -49C is unlikely */
243 			data->sensorsp &= ~SEL_PLACE;
244 	}
245 
246 	if (data->sensorsp & SEL_CORE) {
247 		scfg &= ~SEL_PLACE;	/* Select sensor 0, core1 */
248 		pci_write_config_byte(pdev, REG_TEMP, scfg);
249 		pci_read_config_dword(pdev, REG_TEMP, &temp);
250 		if (!((temp >> 16) & 0xff)) /* if temp is 0 -49C is unlikely */
251 			data->sensorsp &= ~SEL_CORE;
252 	}
253 
254 	data->name = "k8temp";
255 	mutex_init(&data->update_lock);
256 	pci_set_drvdata(pdev, data);
257 
258 	/* Register sysfs hooks */
259 	err = device_create_file(&pdev->dev,
260 			   &sensor_dev_attr_temp1_input.dev_attr);
261 	if (err)
262 		goto exit_remove;
263 
264 	/* sensor can be changed and reports something */
265 	if (data->sensorsp & SEL_PLACE) {
266 		err = device_create_file(&pdev->dev,
267 				   &sensor_dev_attr_temp2_input.dev_attr);
268 		if (err)
269 			goto exit_remove;
270 	}
271 
272 	/* core can be changed and reports something */
273 	if (data->sensorsp & SEL_CORE) {
274 		err = device_create_file(&pdev->dev,
275 				   &sensor_dev_attr_temp3_input.dev_attr);
276 		if (err)
277 			goto exit_remove;
278 		if (data->sensorsp & SEL_PLACE) {
279 			err = device_create_file(&pdev->dev,
280 					   &sensor_dev_attr_temp4_input.
281 					   dev_attr);
282 			if (err)
283 				goto exit_remove;
284 		}
285 	}
286 
287 	err = device_create_file(&pdev->dev, &dev_attr_name);
288 	if (err)
289 		goto exit_remove;
290 
291 	data->hwmon_dev = hwmon_device_register(&pdev->dev);
292 
293 	if (IS_ERR(data->hwmon_dev)) {
294 		err = PTR_ERR(data->hwmon_dev);
295 		goto exit_remove;
296 	}
297 
298 	return 0;
299 
300 exit_remove:
301 	device_remove_file(&pdev->dev,
302 			   &sensor_dev_attr_temp1_input.dev_attr);
303 	device_remove_file(&pdev->dev,
304 			   &sensor_dev_attr_temp2_input.dev_attr);
305 	device_remove_file(&pdev->dev,
306 			   &sensor_dev_attr_temp3_input.dev_attr);
307 	device_remove_file(&pdev->dev,
308 			   &sensor_dev_attr_temp4_input.dev_attr);
309 	device_remove_file(&pdev->dev, &dev_attr_name);
310 exit_free:
311 	pci_set_drvdata(pdev, NULL);
312 	kfree(data);
313 exit:
314 	return err;
315 }
316 
317 static void __devexit k8temp_remove(struct pci_dev *pdev)
318 {
319 	struct k8temp_data *data = pci_get_drvdata(pdev);
320 
321 	hwmon_device_unregister(data->hwmon_dev);
322 	device_remove_file(&pdev->dev,
323 			   &sensor_dev_attr_temp1_input.dev_attr);
324 	device_remove_file(&pdev->dev,
325 			   &sensor_dev_attr_temp2_input.dev_attr);
326 	device_remove_file(&pdev->dev,
327 			   &sensor_dev_attr_temp3_input.dev_attr);
328 	device_remove_file(&pdev->dev,
329 			   &sensor_dev_attr_temp4_input.dev_attr);
330 	device_remove_file(&pdev->dev, &dev_attr_name);
331 	pci_set_drvdata(pdev, NULL);
332 	kfree(data);
333 }
334 
335 static struct pci_driver k8temp_driver = {
336 	.name = "k8temp",
337 	.id_table = k8temp_ids,
338 	.probe = k8temp_probe,
339 	.remove = __devexit_p(k8temp_remove),
340 };
341 
342 module_pci_driver(k8temp_driver);
343 
344 MODULE_AUTHOR("Rudolf Marek <r.marek@assembler.cz>");
345 MODULE_DESCRIPTION("AMD K8 core temperature monitor");
346 MODULE_LICENSE("GPL");
347