xref: /openbmc/linux/drivers/hwmon/k10temp.c (revision f7777dcc)
1 /*
2  * k10temp.c - AMD Family 10h/11h/12h/14h/15h/16h 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 /* 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 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 	/* DDR3 memory implies socket AM3, which is 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 	if (reg_dram_cfg & DDR3_MODE)
120 		return false;
121 
122 	/*
123 	 * Unfortunately it is possible to run a socket AM3 CPU with DDR2
124 	 * memory. We blacklist all the cores which do exist in socket AM2+
125 	 * format. It still isn't perfect, as RB-C2 cores exist in both AM2+
126 	 * and AM3 formats, but that's the best we can do.
127 	 */
128 	return boot_cpu_data.x86_model < 4 ||
129 	       (boot_cpu_data.x86_model == 4 && boot_cpu_data.x86_mask <= 2);
130 }
131 
132 static int k10temp_probe(struct pci_dev *pdev,
133 				   const struct pci_device_id *id)
134 {
135 	struct device *hwmon_dev;
136 	u32 reg_caps, reg_htc;
137 	int unreliable = has_erratum_319(pdev);
138 	int err;
139 
140 	if (unreliable && !force) {
141 		dev_err(&pdev->dev,
142 			"unreliable CPU thermal sensor; monitoring disabled\n");
143 		err = -ENODEV;
144 		goto exit;
145 	}
146 
147 	err = device_create_file(&pdev->dev, &dev_attr_temp1_input);
148 	if (err)
149 		goto exit;
150 	err = device_create_file(&pdev->dev, &dev_attr_temp1_max);
151 	if (err)
152 		goto exit_remove;
153 
154 	pci_read_config_dword(pdev, REG_NORTHBRIDGE_CAPABILITIES, &reg_caps);
155 	pci_read_config_dword(pdev, REG_HARDWARE_THERMAL_CONTROL, &reg_htc);
156 	if ((reg_caps & NB_CAP_HTC) && (reg_htc & HTC_ENABLE)) {
157 		err = device_create_file(&pdev->dev,
158 				&sensor_dev_attr_temp1_crit.dev_attr);
159 		if (err)
160 			goto exit_remove;
161 		err = device_create_file(&pdev->dev,
162 				&sensor_dev_attr_temp1_crit_hyst.dev_attr);
163 		if (err)
164 			goto exit_remove;
165 	}
166 
167 	err = device_create_file(&pdev->dev, &dev_attr_name);
168 	if (err)
169 		goto exit_remove;
170 
171 	hwmon_dev = hwmon_device_register(&pdev->dev);
172 	if (IS_ERR(hwmon_dev)) {
173 		err = PTR_ERR(hwmon_dev);
174 		goto exit_remove;
175 	}
176 	pci_set_drvdata(pdev, hwmon_dev);
177 
178 	if (unreliable && force)
179 		dev_warn(&pdev->dev,
180 			 "unreliable CPU thermal sensor; check erratum 319\n");
181 	return 0;
182 
183 exit_remove:
184 	device_remove_file(&pdev->dev, &dev_attr_name);
185 	device_remove_file(&pdev->dev, &dev_attr_temp1_input);
186 	device_remove_file(&pdev->dev, &dev_attr_temp1_max);
187 	device_remove_file(&pdev->dev,
188 			   &sensor_dev_attr_temp1_crit.dev_attr);
189 	device_remove_file(&pdev->dev,
190 			   &sensor_dev_attr_temp1_crit_hyst.dev_attr);
191 exit:
192 	return err;
193 }
194 
195 static void k10temp_remove(struct pci_dev *pdev)
196 {
197 	hwmon_device_unregister(pci_get_drvdata(pdev));
198 	device_remove_file(&pdev->dev, &dev_attr_name);
199 	device_remove_file(&pdev->dev, &dev_attr_temp1_input);
200 	device_remove_file(&pdev->dev, &dev_attr_temp1_max);
201 	device_remove_file(&pdev->dev,
202 			   &sensor_dev_attr_temp1_crit.dev_attr);
203 	device_remove_file(&pdev->dev,
204 			   &sensor_dev_attr_temp1_crit_hyst.dev_attr);
205 }
206 
207 static DEFINE_PCI_DEVICE_TABLE(k10temp_id_table) = {
208 	{ PCI_VDEVICE(AMD, PCI_DEVICE_ID_AMD_10H_NB_MISC) },
209 	{ PCI_VDEVICE(AMD, PCI_DEVICE_ID_AMD_11H_NB_MISC) },
210 	{ PCI_VDEVICE(AMD, PCI_DEVICE_ID_AMD_CNB17H_F3) },
211 	{ PCI_VDEVICE(AMD, PCI_DEVICE_ID_AMD_15H_NB_F3) },
212 	{ PCI_VDEVICE(AMD, PCI_DEVICE_ID_AMD_15H_M10H_F3) },
213 	{ PCI_VDEVICE(AMD, PCI_DEVICE_ID_AMD_16H_NB_F3) },
214 	{}
215 };
216 MODULE_DEVICE_TABLE(pci, k10temp_id_table);
217 
218 static struct pci_driver k10temp_driver = {
219 	.name = "k10temp",
220 	.id_table = k10temp_id_table,
221 	.probe = k10temp_probe,
222 	.remove = k10temp_remove,
223 };
224 
225 module_pci_driver(k10temp_driver);
226