xref: /openbmc/linux/drivers/hwmon/k8temp.c (revision 367b8112)
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 
35 #define TEMP_FROM_REG(val)	(((((val) >> 16) & 0xff) - 49) * 1000)
36 #define REG_TEMP	0xe4
37 #define SEL_PLACE	0x40
38 #define SEL_CORE	0x04
39 
40 struct k8temp_data {
41 	struct device *hwmon_dev;
42 	struct mutex update_lock;
43 	const char *name;
44 	char valid;		/* zero until following fields are valid */
45 	unsigned long last_updated;	/* in jiffies */
46 
47 	/* registers values */
48 	u8 sensorsp;		/* sensor presence bits - SEL_CORE & SEL_PLACE */
49 	u32 temp[2][2];		/* core, place */
50 };
51 
52 static struct k8temp_data *k8temp_update_device(struct device *dev)
53 {
54 	struct k8temp_data *data = dev_get_drvdata(dev);
55 	struct pci_dev *pdev = to_pci_dev(dev);
56 	u8 tmp;
57 
58 	mutex_lock(&data->update_lock);
59 
60 	if (!data->valid
61 	    || time_after(jiffies, data->last_updated + HZ)) {
62 		pci_read_config_byte(pdev, REG_TEMP, &tmp);
63 		tmp &= ~(SEL_PLACE | SEL_CORE);		/* Select sensor 0, core0 */
64 		pci_write_config_byte(pdev, REG_TEMP, tmp);
65 		pci_read_config_dword(pdev, REG_TEMP, &data->temp[0][0]);
66 
67 		if (data->sensorsp & SEL_PLACE) {
68 			tmp |= SEL_PLACE;	/* Select sensor 1, core0 */
69 			pci_write_config_byte(pdev, REG_TEMP, tmp);
70 			pci_read_config_dword(pdev, REG_TEMP,
71 					      &data->temp[0][1]);
72 		}
73 
74 		if (data->sensorsp & SEL_CORE) {
75 			tmp &= ~SEL_PLACE;	/* Select sensor 0, core1 */
76 			tmp |= SEL_CORE;
77 			pci_write_config_byte(pdev, REG_TEMP, tmp);
78 			pci_read_config_dword(pdev, REG_TEMP,
79 					      &data->temp[1][0]);
80 
81 			if (data->sensorsp & SEL_PLACE) {
82 				tmp |= SEL_PLACE;	/* Select sensor 1, core1 */
83 				pci_write_config_byte(pdev, REG_TEMP, tmp);
84 				pci_read_config_dword(pdev, REG_TEMP,
85 						      &data->temp[1][1]);
86 			}
87 		}
88 
89 		data->last_updated = jiffies;
90 		data->valid = 1;
91 	}
92 
93 	mutex_unlock(&data->update_lock);
94 	return data;
95 }
96 
97 /*
98  * Sysfs stuff
99  */
100 
101 static ssize_t show_name(struct device *dev, struct device_attribute
102 			 *devattr, char *buf)
103 {
104 	struct k8temp_data *data = dev_get_drvdata(dev);
105 
106 	return sprintf(buf, "%s\n", data->name);
107 }
108 
109 
110 static ssize_t show_temp(struct device *dev,
111 			 struct device_attribute *devattr, char *buf)
112 {
113 	struct sensor_device_attribute_2 *attr =
114 	    to_sensor_dev_attr_2(devattr);
115 	int core = attr->nr;
116 	int place = attr->index;
117 	struct k8temp_data *data = k8temp_update_device(dev);
118 
119 	return sprintf(buf, "%d\n",
120 		       TEMP_FROM_REG(data->temp[core][place]));
121 }
122 
123 /* core, place */
124 
125 static SENSOR_DEVICE_ATTR_2(temp1_input, S_IRUGO, show_temp, NULL, 0, 0);
126 static SENSOR_DEVICE_ATTR_2(temp2_input, S_IRUGO, show_temp, NULL, 0, 1);
127 static SENSOR_DEVICE_ATTR_2(temp3_input, S_IRUGO, show_temp, NULL, 1, 0);
128 static SENSOR_DEVICE_ATTR_2(temp4_input, S_IRUGO, show_temp, NULL, 1, 1);
129 static DEVICE_ATTR(name, S_IRUGO, show_name, NULL);
130 
131 static struct pci_device_id k8temp_ids[] = {
132 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_K8_NB_MISC) },
133 	{ 0 },
134 };
135 
136 MODULE_DEVICE_TABLE(pci, k8temp_ids);
137 
138 static int __devinit k8temp_probe(struct pci_dev *pdev,
139 				  const struct pci_device_id *id)
140 {
141 	int err;
142 	u8 scfg;
143 	u32 temp;
144 	struct k8temp_data *data;
145 	u32 cpuid = cpuid_eax(1);
146 
147 	/* this feature should be available since SH-C0 core */
148 	if ((cpuid == 0xf40) || (cpuid == 0xf50) || (cpuid == 0xf51)) {
149 		err = -ENODEV;
150 		goto exit;
151 	}
152 
153 	if (!(data = kzalloc(sizeof(struct k8temp_data), GFP_KERNEL))) {
154 		err = -ENOMEM;
155 		goto exit;
156 	}
157 
158 	pci_read_config_byte(pdev, REG_TEMP, &scfg);
159 	scfg &= ~(SEL_PLACE | SEL_CORE);		/* Select sensor 0, core0 */
160 	pci_write_config_byte(pdev, REG_TEMP, scfg);
161 	pci_read_config_byte(pdev, REG_TEMP, &scfg);
162 
163 	if (scfg & (SEL_PLACE | SEL_CORE)) {
164 		dev_err(&pdev->dev, "Configuration bit(s) stuck at 1!\n");
165 		err = -ENODEV;
166 		goto exit_free;
167 	}
168 
169 	scfg |= (SEL_PLACE | SEL_CORE);
170 	pci_write_config_byte(pdev, REG_TEMP, scfg);
171 
172 	/* now we know if we can change core and/or sensor */
173 	pci_read_config_byte(pdev, REG_TEMP, &data->sensorsp);
174 
175 	if (data->sensorsp & SEL_PLACE) {
176 		scfg &= ~SEL_CORE;	/* Select sensor 1, core0 */
177 		pci_write_config_byte(pdev, REG_TEMP, scfg);
178 		pci_read_config_dword(pdev, REG_TEMP, &temp);
179 		scfg |= SEL_CORE;	/* prepare for next selection */
180 		if (!((temp >> 16) & 0xff))	/* if temp is 0 -49C is not likely */
181 			data->sensorsp &= ~SEL_PLACE;
182 	}
183 
184 	if (data->sensorsp & SEL_CORE) {
185 		scfg &= ~SEL_PLACE;	/* Select sensor 0, core1 */
186 		pci_write_config_byte(pdev, REG_TEMP, scfg);
187 		pci_read_config_dword(pdev, REG_TEMP, &temp);
188 		if (!((temp >> 16) & 0xff))	/* if temp is 0 -49C is not likely */
189 			data->sensorsp &= ~SEL_CORE;
190 	}
191 
192 	data->name = "k8temp";
193 	mutex_init(&data->update_lock);
194 	dev_set_drvdata(&pdev->dev, data);
195 
196 	/* Register sysfs hooks */
197 	err = device_create_file(&pdev->dev,
198 			   &sensor_dev_attr_temp1_input.dev_attr);
199 	if (err)
200 		goto exit_remove;
201 
202 	/* sensor can be changed and reports something */
203 	if (data->sensorsp & SEL_PLACE) {
204 		err = device_create_file(&pdev->dev,
205 				   &sensor_dev_attr_temp2_input.dev_attr);
206 		if (err)
207 			goto exit_remove;
208 	}
209 
210 	/* core can be changed and reports something */
211 	if (data->sensorsp & SEL_CORE) {
212 		err = device_create_file(&pdev->dev,
213 				   &sensor_dev_attr_temp3_input.dev_attr);
214 		if (err)
215 			goto exit_remove;
216 		if (data->sensorsp & SEL_PLACE)
217 			err = device_create_file(&pdev->dev,
218 					   &sensor_dev_attr_temp4_input.
219 					   dev_attr);
220 			if (err)
221 				goto exit_remove;
222 	}
223 
224 	err = device_create_file(&pdev->dev, &dev_attr_name);
225 	if (err)
226 		goto exit_remove;
227 
228 	data->hwmon_dev = hwmon_device_register(&pdev->dev);
229 
230 	if (IS_ERR(data->hwmon_dev)) {
231 		err = PTR_ERR(data->hwmon_dev);
232 		goto exit_remove;
233 	}
234 
235 	return 0;
236 
237 exit_remove:
238 	device_remove_file(&pdev->dev,
239 			   &sensor_dev_attr_temp1_input.dev_attr);
240 	device_remove_file(&pdev->dev,
241 			   &sensor_dev_attr_temp2_input.dev_attr);
242 	device_remove_file(&pdev->dev,
243 			   &sensor_dev_attr_temp3_input.dev_attr);
244 	device_remove_file(&pdev->dev,
245 			   &sensor_dev_attr_temp4_input.dev_attr);
246 	device_remove_file(&pdev->dev, &dev_attr_name);
247 exit_free:
248 	dev_set_drvdata(&pdev->dev, NULL);
249 	kfree(data);
250 exit:
251 	return err;
252 }
253 
254 static void __devexit k8temp_remove(struct pci_dev *pdev)
255 {
256 	struct k8temp_data *data = dev_get_drvdata(&pdev->dev);
257 
258 	hwmon_device_unregister(data->hwmon_dev);
259 	device_remove_file(&pdev->dev,
260 			   &sensor_dev_attr_temp1_input.dev_attr);
261 	device_remove_file(&pdev->dev,
262 			   &sensor_dev_attr_temp2_input.dev_attr);
263 	device_remove_file(&pdev->dev,
264 			   &sensor_dev_attr_temp3_input.dev_attr);
265 	device_remove_file(&pdev->dev,
266 			   &sensor_dev_attr_temp4_input.dev_attr);
267 	device_remove_file(&pdev->dev, &dev_attr_name);
268 	dev_set_drvdata(&pdev->dev, NULL);
269 	kfree(data);
270 }
271 
272 static struct pci_driver k8temp_driver = {
273 	.name = "k8temp",
274 	.id_table = k8temp_ids,
275 	.probe = k8temp_probe,
276 	.remove = __devexit_p(k8temp_remove),
277 };
278 
279 static int __init k8temp_init(void)
280 {
281 	return pci_register_driver(&k8temp_driver);
282 }
283 
284 static void __exit k8temp_exit(void)
285 {
286 	pci_unregister_driver(&k8temp_driver);
287 }
288 
289 MODULE_AUTHOR("Rudolf Marek <r.marek@assembler.cz>");
290 MODULE_DESCRIPTION("AMD K8 core temperature monitor");
291 MODULE_LICENSE("GPL");
292 
293 module_init(k8temp_init)
294 module_exit(k8temp_exit)
295