xref: /openbmc/linux/drivers/hwmon/k10temp.c (revision b6dcefde)
1 /*
2  * k10temp.c - AMD Family 10h/11h processor hardware monitoring
3  *
4  * Copyright (c) 2009 Clemens Ladisch <clemens@ladisch.de>
5  *
6  *
7  * This driver is free software; you can redistribute it and/or
8  * modify it under the terms of the GNU General Public License; either
9  * version 2 of the License, or (at your option) any later version.
10  *
11  * This driver is distributed in the hope that it will be useful,
12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
14  * See the GNU General Public License for more details.
15  *
16  * You should have received a copy of the GNU General Public License
17  * along with this driver; if not, see <http://www.gnu.org/licenses/>.
18  */
19 
20 #include <linux/err.h>
21 #include <linux/hwmon.h>
22 #include <linux/hwmon-sysfs.h>
23 #include <linux/init.h>
24 #include <linux/module.h>
25 #include <linux/pci.h>
26 #include <asm/processor.h>
27 
28 MODULE_DESCRIPTION("AMD Family 10h/11h CPU core temperature monitor");
29 MODULE_AUTHOR("Clemens Ladisch <clemens@ladisch.de>");
30 MODULE_LICENSE("GPL");
31 
32 static bool force;
33 module_param(force, bool, 0444);
34 MODULE_PARM_DESC(force, "force loading on processors with erratum 319");
35 
36 /* CPUID function 0x80000001, ebx */
37 #define CPUID_PKGTYPE_MASK	0xf0000000
38 #define CPUID_PKGTYPE_F		0x00000000
39 #define CPUID_PKGTYPE_AM2R2_AM3	0x10000000
40 
41 /* DRAM controller (PCI function 2) */
42 #define REG_DCT0_CONFIG_HIGH		0x094
43 #define  DDR3_MODE			0x00000100
44 
45 /* miscellaneous (PCI function 3) */
46 #define REG_HARDWARE_THERMAL_CONTROL	0x64
47 #define  HTC_ENABLE			0x00000001
48 
49 #define REG_REPORTED_TEMPERATURE	0xa4
50 
51 #define REG_NORTHBRIDGE_CAPABILITIES	0xe8
52 #define  NB_CAP_HTC			0x00000400
53 
54 static ssize_t show_temp(struct device *dev,
55 			 struct device_attribute *attr, char *buf)
56 {
57 	u32 regval;
58 
59 	pci_read_config_dword(to_pci_dev(dev),
60 			      REG_REPORTED_TEMPERATURE, &regval);
61 	return sprintf(buf, "%u\n", (regval >> 21) * 125);
62 }
63 
64 static ssize_t show_temp_max(struct device *dev,
65 			     struct device_attribute *attr, char *buf)
66 {
67 	return sprintf(buf, "%d\n", 70 * 1000);
68 }
69 
70 static ssize_t show_temp_crit(struct device *dev,
71 			      struct device_attribute *devattr, char *buf)
72 {
73 	struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
74 	int show_hyst = attr->index;
75 	u32 regval;
76 	int value;
77 
78 	pci_read_config_dword(to_pci_dev(dev),
79 			      REG_HARDWARE_THERMAL_CONTROL, &regval);
80 	value = ((regval >> 16) & 0x7f) * 500 + 52000;
81 	if (show_hyst)
82 		value -= ((regval >> 24) & 0xf) * 500;
83 	return sprintf(buf, "%d\n", value);
84 }
85 
86 static ssize_t show_name(struct device *dev,
87 			 struct device_attribute *attr, char *buf)
88 {
89 	return sprintf(buf, "k10temp\n");
90 }
91 
92 static DEVICE_ATTR(temp1_input, S_IRUGO, show_temp, NULL);
93 static DEVICE_ATTR(temp1_max, S_IRUGO, show_temp_max, NULL);
94 static SENSOR_DEVICE_ATTR(temp1_crit, S_IRUGO, show_temp_crit, NULL, 0);
95 static SENSOR_DEVICE_ATTR(temp1_crit_hyst, S_IRUGO, show_temp_crit, NULL, 1);
96 static DEVICE_ATTR(name, S_IRUGO, show_name, NULL);
97 
98 static bool __devinit has_erratum_319(struct pci_dev *pdev)
99 {
100 	u32 pkg_type, reg_dram_cfg;
101 
102 	if (boot_cpu_data.x86 != 0x10)
103 		return false;
104 
105 	/*
106 	 * Erratum 319: The thermal sensor of Socket F/AM2+ processors
107 	 *              may be unreliable.
108 	 */
109 	pkg_type = cpuid_ebx(0x80000001) & CPUID_PKGTYPE_MASK;
110 	if (pkg_type == CPUID_PKGTYPE_F)
111 		return true;
112 	if (pkg_type != CPUID_PKGTYPE_AM2R2_AM3)
113 		return false;
114 
115 	/* Differentiate between AM2+ (bad) and AM3 (good) */
116 	pci_bus_read_config_dword(pdev->bus,
117 				  PCI_DEVFN(PCI_SLOT(pdev->devfn), 2),
118 				  REG_DCT0_CONFIG_HIGH, &reg_dram_cfg);
119 	return !(reg_dram_cfg & DDR3_MODE);
120 }
121 
122 static int __devinit k10temp_probe(struct pci_dev *pdev,
123 				   const struct pci_device_id *id)
124 {
125 	struct device *hwmon_dev;
126 	u32 reg_caps, reg_htc;
127 	int unreliable = has_erratum_319(pdev);
128 	int err;
129 
130 	if (unreliable && !force) {
131 		dev_err(&pdev->dev,
132 			"unreliable CPU thermal sensor; monitoring disabled\n");
133 		err = -ENODEV;
134 		goto exit;
135 	}
136 
137 	err = device_create_file(&pdev->dev, &dev_attr_temp1_input);
138 	if (err)
139 		goto exit;
140 	err = device_create_file(&pdev->dev, &dev_attr_temp1_max);
141 	if (err)
142 		goto exit_remove;
143 
144 	pci_read_config_dword(pdev, REG_NORTHBRIDGE_CAPABILITIES, &reg_caps);
145 	pci_read_config_dword(pdev, REG_HARDWARE_THERMAL_CONTROL, &reg_htc);
146 	if ((reg_caps & NB_CAP_HTC) && (reg_htc & HTC_ENABLE)) {
147 		err = device_create_file(&pdev->dev,
148 				&sensor_dev_attr_temp1_crit.dev_attr);
149 		if (err)
150 			goto exit_remove;
151 		err = device_create_file(&pdev->dev,
152 				&sensor_dev_attr_temp1_crit_hyst.dev_attr);
153 		if (err)
154 			goto exit_remove;
155 	}
156 
157 	err = device_create_file(&pdev->dev, &dev_attr_name);
158 	if (err)
159 		goto exit_remove;
160 
161 	hwmon_dev = hwmon_device_register(&pdev->dev);
162 	if (IS_ERR(hwmon_dev)) {
163 		err = PTR_ERR(hwmon_dev);
164 		goto exit_remove;
165 	}
166 	dev_set_drvdata(&pdev->dev, hwmon_dev);
167 
168 	if (unreliable && force)
169 		dev_warn(&pdev->dev,
170 			 "unreliable CPU thermal sensor; check erratum 319\n");
171 	return 0;
172 
173 exit_remove:
174 	device_remove_file(&pdev->dev, &dev_attr_name);
175 	device_remove_file(&pdev->dev, &dev_attr_temp1_input);
176 	device_remove_file(&pdev->dev, &dev_attr_temp1_max);
177 	device_remove_file(&pdev->dev,
178 			   &sensor_dev_attr_temp1_crit.dev_attr);
179 	device_remove_file(&pdev->dev,
180 			   &sensor_dev_attr_temp1_crit_hyst.dev_attr);
181 exit:
182 	return err;
183 }
184 
185 static void __devexit k10temp_remove(struct pci_dev *pdev)
186 {
187 	hwmon_device_unregister(dev_get_drvdata(&pdev->dev));
188 	device_remove_file(&pdev->dev, &dev_attr_name);
189 	device_remove_file(&pdev->dev, &dev_attr_temp1_input);
190 	device_remove_file(&pdev->dev, &dev_attr_temp1_max);
191 	device_remove_file(&pdev->dev,
192 			   &sensor_dev_attr_temp1_crit.dev_attr);
193 	device_remove_file(&pdev->dev,
194 			   &sensor_dev_attr_temp1_crit_hyst.dev_attr);
195 	dev_set_drvdata(&pdev->dev, NULL);
196 }
197 
198 static const struct pci_device_id k10temp_id_table[] = {
199 	{ PCI_VDEVICE(AMD, PCI_DEVICE_ID_AMD_10H_NB_MISC) },
200 	{ PCI_VDEVICE(AMD, PCI_DEVICE_ID_AMD_11H_NB_MISC) },
201 	{}
202 };
203 MODULE_DEVICE_TABLE(pci, k10temp_id_table);
204 
205 static struct pci_driver k10temp_driver = {
206 	.name = "k10temp",
207 	.id_table = k10temp_id_table,
208 	.probe = k10temp_probe,
209 	.remove = __devexit_p(k10temp_remove),
210 };
211 
212 static int __init k10temp_init(void)
213 {
214 	return pci_register_driver(&k10temp_driver);
215 }
216 
217 static void __exit k10temp_exit(void)
218 {
219 	pci_unregister_driver(&k10temp_driver);
220 }
221 
222 module_init(k10temp_init)
223 module_exit(k10temp_exit)
224