xref: /openbmc/linux/drivers/hwmon/k10temp.c (revision 63dc02bd)
1 /*
2  * k10temp.c - AMD Family 10h/11h/12h/14h/15h 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+ 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 /* PCI-IDs for Northbridge devices not used anywhere else */
37 #define PCI_DEVICE_ID_AMD_15H_M10H_NB_F3	0x1403
38 
39 /* CPUID function 0x80000001, ebx */
40 #define CPUID_PKGTYPE_MASK	0xf0000000
41 #define CPUID_PKGTYPE_F		0x00000000
42 #define CPUID_PKGTYPE_AM2R2_AM3	0x10000000
43 
44 /* DRAM controller (PCI function 2) */
45 #define REG_DCT0_CONFIG_HIGH		0x094
46 #define  DDR3_MODE			0x00000100
47 
48 /* miscellaneous (PCI function 3) */
49 #define REG_HARDWARE_THERMAL_CONTROL	0x64
50 #define  HTC_ENABLE			0x00000001
51 
52 #define REG_REPORTED_TEMPERATURE	0xa4
53 
54 #define REG_NORTHBRIDGE_CAPABILITIES	0xe8
55 #define  NB_CAP_HTC			0x00000400
56 
57 static ssize_t show_temp(struct device *dev,
58 			 struct device_attribute *attr, char *buf)
59 {
60 	u32 regval;
61 
62 	pci_read_config_dword(to_pci_dev(dev),
63 			      REG_REPORTED_TEMPERATURE, &regval);
64 	return sprintf(buf, "%u\n", (regval >> 21) * 125);
65 }
66 
67 static ssize_t show_temp_max(struct device *dev,
68 			     struct device_attribute *attr, char *buf)
69 {
70 	return sprintf(buf, "%d\n", 70 * 1000);
71 }
72 
73 static ssize_t show_temp_crit(struct device *dev,
74 			      struct device_attribute *devattr, char *buf)
75 {
76 	struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
77 	int show_hyst = attr->index;
78 	u32 regval;
79 	int value;
80 
81 	pci_read_config_dword(to_pci_dev(dev),
82 			      REG_HARDWARE_THERMAL_CONTROL, &regval);
83 	value = ((regval >> 16) & 0x7f) * 500 + 52000;
84 	if (show_hyst)
85 		value -= ((regval >> 24) & 0xf) * 500;
86 	return sprintf(buf, "%d\n", value);
87 }
88 
89 static ssize_t show_name(struct device *dev,
90 			 struct device_attribute *attr, char *buf)
91 {
92 	return sprintf(buf, "k10temp\n");
93 }
94 
95 static DEVICE_ATTR(temp1_input, S_IRUGO, show_temp, NULL);
96 static DEVICE_ATTR(temp1_max, S_IRUGO, show_temp_max, NULL);
97 static SENSOR_DEVICE_ATTR(temp1_crit, S_IRUGO, show_temp_crit, NULL, 0);
98 static SENSOR_DEVICE_ATTR(temp1_crit_hyst, S_IRUGO, show_temp_crit, NULL, 1);
99 static DEVICE_ATTR(name, S_IRUGO, show_name, NULL);
100 
101 static bool __devinit has_erratum_319(struct pci_dev *pdev)
102 {
103 	u32 pkg_type, reg_dram_cfg;
104 
105 	if (boot_cpu_data.x86 != 0x10)
106 		return false;
107 
108 	/*
109 	 * Erratum 319: The thermal sensor of Socket F/AM2+ processors
110 	 *              may be unreliable.
111 	 */
112 	pkg_type = cpuid_ebx(0x80000001) & CPUID_PKGTYPE_MASK;
113 	if (pkg_type == CPUID_PKGTYPE_F)
114 		return true;
115 	if (pkg_type != CPUID_PKGTYPE_AM2R2_AM3)
116 		return false;
117 
118 	/* DDR3 memory implies socket AM3, which is good */
119 	pci_bus_read_config_dword(pdev->bus,
120 				  PCI_DEVFN(PCI_SLOT(pdev->devfn), 2),
121 				  REG_DCT0_CONFIG_HIGH, &reg_dram_cfg);
122 	if (reg_dram_cfg & DDR3_MODE)
123 		return false;
124 
125 	/*
126 	 * Unfortunately it is possible to run a socket AM3 CPU with DDR2
127 	 * memory. We blacklist all the cores which do exist in socket AM2+
128 	 * format. It still isn't perfect, as RB-C2 cores exist in both AM2+
129 	 * and AM3 formats, but that's the best we can do.
130 	 */
131 	return boot_cpu_data.x86_model < 4 ||
132 	       (boot_cpu_data.x86_model == 4 && boot_cpu_data.x86_mask <= 2);
133 }
134 
135 static int __devinit k10temp_probe(struct pci_dev *pdev,
136 				   const struct pci_device_id *id)
137 {
138 	struct device *hwmon_dev;
139 	u32 reg_caps, reg_htc;
140 	int unreliable = has_erratum_319(pdev);
141 	int err;
142 
143 	if (unreliable && !force) {
144 		dev_err(&pdev->dev,
145 			"unreliable CPU thermal sensor; monitoring disabled\n");
146 		err = -ENODEV;
147 		goto exit;
148 	}
149 
150 	err = device_create_file(&pdev->dev, &dev_attr_temp1_input);
151 	if (err)
152 		goto exit;
153 	err = device_create_file(&pdev->dev, &dev_attr_temp1_max);
154 	if (err)
155 		goto exit_remove;
156 
157 	pci_read_config_dword(pdev, REG_NORTHBRIDGE_CAPABILITIES, &reg_caps);
158 	pci_read_config_dword(pdev, REG_HARDWARE_THERMAL_CONTROL, &reg_htc);
159 	if ((reg_caps & NB_CAP_HTC) && (reg_htc & HTC_ENABLE)) {
160 		err = device_create_file(&pdev->dev,
161 				&sensor_dev_attr_temp1_crit.dev_attr);
162 		if (err)
163 			goto exit_remove;
164 		err = device_create_file(&pdev->dev,
165 				&sensor_dev_attr_temp1_crit_hyst.dev_attr);
166 		if (err)
167 			goto exit_remove;
168 	}
169 
170 	err = device_create_file(&pdev->dev, &dev_attr_name);
171 	if (err)
172 		goto exit_remove;
173 
174 	hwmon_dev = hwmon_device_register(&pdev->dev);
175 	if (IS_ERR(hwmon_dev)) {
176 		err = PTR_ERR(hwmon_dev);
177 		goto exit_remove;
178 	}
179 	pci_set_drvdata(pdev, hwmon_dev);
180 
181 	if (unreliable && force)
182 		dev_warn(&pdev->dev,
183 			 "unreliable CPU thermal sensor; check erratum 319\n");
184 	return 0;
185 
186 exit_remove:
187 	device_remove_file(&pdev->dev, &dev_attr_name);
188 	device_remove_file(&pdev->dev, &dev_attr_temp1_input);
189 	device_remove_file(&pdev->dev, &dev_attr_temp1_max);
190 	device_remove_file(&pdev->dev,
191 			   &sensor_dev_attr_temp1_crit.dev_attr);
192 	device_remove_file(&pdev->dev,
193 			   &sensor_dev_attr_temp1_crit_hyst.dev_attr);
194 exit:
195 	return err;
196 }
197 
198 static void __devexit k10temp_remove(struct pci_dev *pdev)
199 {
200 	hwmon_device_unregister(pci_get_drvdata(pdev));
201 	device_remove_file(&pdev->dev, &dev_attr_name);
202 	device_remove_file(&pdev->dev, &dev_attr_temp1_input);
203 	device_remove_file(&pdev->dev, &dev_attr_temp1_max);
204 	device_remove_file(&pdev->dev,
205 			   &sensor_dev_attr_temp1_crit.dev_attr);
206 	device_remove_file(&pdev->dev,
207 			   &sensor_dev_attr_temp1_crit_hyst.dev_attr);
208 	pci_set_drvdata(pdev, NULL);
209 }
210 
211 static DEFINE_PCI_DEVICE_TABLE(k10temp_id_table) = {
212 	{ PCI_VDEVICE(AMD, PCI_DEVICE_ID_AMD_10H_NB_MISC) },
213 	{ PCI_VDEVICE(AMD, PCI_DEVICE_ID_AMD_11H_NB_MISC) },
214 	{ PCI_VDEVICE(AMD, PCI_DEVICE_ID_AMD_CNB17H_F3) },
215 	{ PCI_VDEVICE(AMD, PCI_DEVICE_ID_AMD_15H_NB_F3) },
216 	{ PCI_VDEVICE(AMD, PCI_DEVICE_ID_AMD_15H_M10H_NB_F3) },
217 	{}
218 };
219 MODULE_DEVICE_TABLE(pci, k10temp_id_table);
220 
221 static struct pci_driver k10temp_driver = {
222 	.name = "k10temp",
223 	.id_table = k10temp_id_table,
224 	.probe = k10temp_probe,
225 	.remove = __devexit_p(k10temp_remove),
226 };
227 
228 static int __init k10temp_init(void)
229 {
230 	return pci_register_driver(&k10temp_driver);
231 }
232 
233 static void __exit k10temp_exit(void)
234 {
235 	pci_unregister_driver(&k10temp_driver);
236 }
237 
238 module_init(k10temp_init)
239 module_exit(k10temp_exit)
240