blob: 523f8fb9e7d92402f1fa1b6ead69766fb428430a [file] [log] [blame]
Andreas Herrmann512d1022011-05-25 20:43:31 +02001/*
2 * fam15h_power.c - AMD Family 15h processor power monitoring
3 *
4 * Copyright (c) 2011 Advanced Micro Devices, Inc.
5 * Author: Andreas Herrmann <andreas.herrmann3@amd.com>
6 *
7 *
8 * This driver is free software; you can redistribute it and/or
9 * modify it under the terms of the GNU General Public License; either
10 * version 2 of the License, or (at your option) any later version.
11 *
12 * This driver is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
15 * See the GNU General Public License for more details.
16 *
17 * You should have received a copy of the GNU General Public License
18 * along with this driver; if not, see <http://www.gnu.org/licenses/>.
19 */
20
21#include <linux/err.h>
22#include <linux/hwmon.h>
23#include <linux/hwmon-sysfs.h>
24#include <linux/init.h>
25#include <linux/module.h>
26#include <linux/pci.h>
27#include <linux/bitops.h>
28#include <asm/processor.h>
29
30MODULE_DESCRIPTION("AMD Family 15h CPU processor power monitor");
31MODULE_AUTHOR("Andreas Herrmann <andreas.herrmann3@amd.com>");
32MODULE_LICENSE("GPL");
33
34/* D18F3 */
35#define REG_NORTHBRIDGE_CAP 0xe8
36
37/* D18F4 */
38#define REG_PROCESSOR_TDP 0x1b8
39
40/* D18F5 */
41#define REG_TDP_RUNNING_AVERAGE 0xe0
42#define REG_TDP_LIMIT3 0xe8
43
44struct fam15h_power_data {
45 struct device *hwmon_dev;
46 unsigned int tdp_to_watts;
47 unsigned int base_tdp;
48 unsigned int processor_pwr_watts;
49};
50
51static ssize_t show_power(struct device *dev,
52 struct device_attribute *attr, char *buf)
53{
54 u32 val, tdp_limit, running_avg_range;
55 s32 running_avg_capture;
56 u64 curr_pwr_watts;
57 struct pci_dev *f4 = to_pci_dev(dev);
58 struct fam15h_power_data *data = dev_get_drvdata(dev);
59
60 pci_bus_read_config_dword(f4->bus, PCI_DEVFN(PCI_SLOT(f4->devfn), 5),
61 REG_TDP_RUNNING_AVERAGE, &val);
62 running_avg_capture = (val >> 4) & 0x3fffff;
63 running_avg_capture = sign_extend32(running_avg_capture, 22);
64 running_avg_range = val & 0xf;
65
66 pci_bus_read_config_dword(f4->bus, PCI_DEVFN(PCI_SLOT(f4->devfn), 5),
67 REG_TDP_LIMIT3, &val);
68
69 tdp_limit = val >> 16;
70 curr_pwr_watts = tdp_limit + data->base_tdp -
71 (s32)(running_avg_capture >> (running_avg_range + 1));
72 curr_pwr_watts *= data->tdp_to_watts;
73
74 /*
75 * Convert to microWatt
76 *
77 * power is in Watt provided as fixed point integer with
78 * scaling factor 1/(2^16). For conversion we use
79 * (10^6)/(2^16) = 15625/(2^10)
80 */
81 curr_pwr_watts = (curr_pwr_watts * 15625) >> 10;
82 return sprintf(buf, "%u\n", (unsigned int) curr_pwr_watts);
83}
84static DEVICE_ATTR(power1_input, S_IRUGO, show_power, NULL);
85
86static ssize_t show_power_crit(struct device *dev,
87 struct device_attribute *attr, char *buf)
88{
89 struct fam15h_power_data *data = dev_get_drvdata(dev);
90
91 return sprintf(buf, "%u\n", data->processor_pwr_watts);
92}
93static DEVICE_ATTR(power1_crit, S_IRUGO, show_power_crit, NULL);
94
95static ssize_t show_name(struct device *dev,
96 struct device_attribute *attr, char *buf)
97{
98 return sprintf(buf, "fam15h_power\n");
99}
100static DEVICE_ATTR(name, S_IRUGO, show_name, NULL);
101
102static struct attribute *fam15h_power_attrs[] = {
103 &dev_attr_power1_input.attr,
104 &dev_attr_power1_crit.attr,
105 &dev_attr_name.attr,
106 NULL
107};
108
109static const struct attribute_group fam15h_power_attr_group = {
110 .attrs = fam15h_power_attrs,
111};
112
113static bool __devinit fam15h_power_is_internal_node0(struct pci_dev *f4)
114{
115 u32 val;
116
117 pci_bus_read_config_dword(f4->bus, PCI_DEVFN(PCI_SLOT(f4->devfn), 3),
118 REG_NORTHBRIDGE_CAP, &val);
119 if ((val & BIT(29)) && ((val >> 30) & 3))
120 return false;
121
122 return true;
123}
124
125static void __devinit fam15h_power_init_data(struct pci_dev *f4,
126 struct fam15h_power_data *data)
127{
128 u32 val;
129 u64 tmp;
130
131 pci_read_config_dword(f4, REG_PROCESSOR_TDP, &val);
132 data->base_tdp = val >> 16;
133 tmp = val & 0xffff;
134
135 pci_bus_read_config_dword(f4->bus, PCI_DEVFN(PCI_SLOT(f4->devfn), 5),
136 REG_TDP_LIMIT3, &val);
137
138 data->tdp_to_watts = ((val & 0x3ff) << 6) | ((val >> 10) & 0x3f);
139 tmp *= data->tdp_to_watts;
140
141 /* result not allowed to be >= 256W */
142 if ((tmp >> 16) >= 256)
143 dev_warn(&f4->dev, "Bogus value for ProcessorPwrWatts "
144 "(processor_pwr_watts>=%u)\n",
145 (unsigned int) (tmp >> 16));
146
147 /* convert to microWatt */
148 data->processor_pwr_watts = (tmp * 15625) >> 10;
149}
150
151static int __devinit fam15h_power_probe(struct pci_dev *pdev,
152 const struct pci_device_id *id)
153{
154 struct fam15h_power_data *data;
155 struct device *dev;
156 int err;
157
158 if (!fam15h_power_is_internal_node0(pdev)) {
159 err = -ENODEV;
160 goto exit;
161 }
162
163 data = kzalloc(sizeof(struct fam15h_power_data), GFP_KERNEL);
164 if (!data) {
165 err = -ENOMEM;
166 goto exit;
167 }
168 fam15h_power_init_data(pdev, data);
169 dev = &pdev->dev;
170
171 dev_set_drvdata(dev, data);
172 err = sysfs_create_group(&dev->kobj, &fam15h_power_attr_group);
173 if (err)
174 goto exit_free_data;
175
176 data->hwmon_dev = hwmon_device_register(dev);
177 if (IS_ERR(data->hwmon_dev)) {
178 err = PTR_ERR(data->hwmon_dev);
179 goto exit_remove_group;
180 }
181
182 return 0;
183
184exit_remove_group:
185 sysfs_remove_group(&dev->kobj, &fam15h_power_attr_group);
186exit_free_data:
187 kfree(data);
188exit:
189 return err;
190}
191
192static void __devexit fam15h_power_remove(struct pci_dev *pdev)
193{
194 struct device *dev;
195 struct fam15h_power_data *data;
196
197 dev = &pdev->dev;
198 data = dev_get_drvdata(dev);
199 hwmon_device_unregister(data->hwmon_dev);
200 sysfs_remove_group(&dev->kobj, &fam15h_power_attr_group);
201 dev_set_drvdata(dev, NULL);
202 kfree(data);
203}
204
205static DEFINE_PCI_DEVICE_TABLE(fam15h_power_id_table) = {
206 { PCI_VDEVICE(AMD, PCI_DEVICE_ID_AMD_15H_NB_F4) },
207 {}
208};
209MODULE_DEVICE_TABLE(pci, fam15h_power_id_table);
210
211static struct pci_driver fam15h_power_driver = {
212 .name = "fam15h_power",
213 .id_table = fam15h_power_id_table,
214 .probe = fam15h_power_probe,
215 .remove = __devexit_p(fam15h_power_remove),
216};
217
218static int __init fam15h_power_init(void)
219{
220 return pci_register_driver(&fam15h_power_driver);
221}
222
223static void __exit fam15h_power_exit(void)
224{
225 pci_unregister_driver(&fam15h_power_driver);
226}
227
228module_init(fam15h_power_init)
229module_exit(fam15h_power_exit)