Version:  2.0.40 2.2.26 2.4.37 3.0 3.1 3.2 3.3 3.4 3.5 3.6 3.7 3.8 3.9 3.10 3.11 3.12 3.13 3.14 3.15 3.16

Linux/drivers/hwmon/fam15h_power.c

  1 /*
  2  * fam15h_power.c - AMD Family 15h processor power monitoring
  3  *
  4  * Copyright (c) 2011 Advanced Micro Devices, Inc.
  5  * Author: Andreas Herrmann <herrmann.der.user@googlemail.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 
 30 MODULE_DESCRIPTION("AMD Family 15h CPU processor power monitor");
 31 MODULE_AUTHOR("Andreas Herrmann <herrmann.der.user@googlemail.com>");
 32 MODULE_LICENSE("GPL");
 33 
 34 /* Family 16h Northbridge's function 4 PCI ID */
 35 #define PCI_DEVICE_ID_AMD_16H_NB_F4     0x1534
 36 
 37 /* D18F3 */
 38 #define REG_NORTHBRIDGE_CAP             0xe8
 39 
 40 /* D18F4 */
 41 #define REG_PROCESSOR_TDP               0x1b8
 42 
 43 /* D18F5 */
 44 #define REG_TDP_RUNNING_AVERAGE         0xe0
 45 #define REG_TDP_LIMIT3                  0xe8
 46 
 47 struct fam15h_power_data {
 48         struct device *hwmon_dev;
 49         unsigned int tdp_to_watts;
 50         unsigned int base_tdp;
 51         unsigned int processor_pwr_watts;
 52 };
 53 
 54 static ssize_t show_power(struct device *dev,
 55                           struct device_attribute *attr, char *buf)
 56 {
 57         u32 val, tdp_limit, running_avg_range;
 58         s32 running_avg_capture;
 59         u64 curr_pwr_watts;
 60         struct pci_dev *f4 = to_pci_dev(dev);
 61         struct fam15h_power_data *data = dev_get_drvdata(dev);
 62 
 63         pci_bus_read_config_dword(f4->bus, PCI_DEVFN(PCI_SLOT(f4->devfn), 5),
 64                                   REG_TDP_RUNNING_AVERAGE, &val);
 65         running_avg_capture = (val >> 4) & 0x3fffff;
 66         running_avg_capture = sign_extend32(running_avg_capture, 21);
 67         running_avg_range = (val & 0xf) + 1;
 68 
 69         pci_bus_read_config_dword(f4->bus, PCI_DEVFN(PCI_SLOT(f4->devfn), 5),
 70                                   REG_TDP_LIMIT3, &val);
 71 
 72         tdp_limit = val >> 16;
 73         curr_pwr_watts = ((u64)(tdp_limit +
 74                                 data->base_tdp)) << running_avg_range;
 75         curr_pwr_watts -= running_avg_capture;
 76         curr_pwr_watts *= data->tdp_to_watts;
 77 
 78         /*
 79          * Convert to microWatt
 80          *
 81          * power is in Watt provided as fixed point integer with
 82          * scaling factor 1/(2^16).  For conversion we use
 83          * (10^6)/(2^16) = 15625/(2^10)
 84          */
 85         curr_pwr_watts = (curr_pwr_watts * 15625) >> (10 + running_avg_range);
 86         return sprintf(buf, "%u\n", (unsigned int) curr_pwr_watts);
 87 }
 88 static DEVICE_ATTR(power1_input, S_IRUGO, show_power, NULL);
 89 
 90 static ssize_t show_power_crit(struct device *dev,
 91                                struct device_attribute *attr, char *buf)
 92 {
 93         struct fam15h_power_data *data = dev_get_drvdata(dev);
 94 
 95         return sprintf(buf, "%u\n", data->processor_pwr_watts);
 96 }
 97 static DEVICE_ATTR(power1_crit, S_IRUGO, show_power_crit, NULL);
 98 
 99 static ssize_t show_name(struct device *dev,
100                          struct device_attribute *attr, char *buf)
101 {
102         return sprintf(buf, "fam15h_power\n");
103 }
104 static DEVICE_ATTR(name, S_IRUGO, show_name, NULL);
105 
106 static struct attribute *fam15h_power_attrs[] = {
107         &dev_attr_power1_input.attr,
108         &dev_attr_power1_crit.attr,
109         &dev_attr_name.attr,
110         NULL
111 };
112 
113 static const struct attribute_group fam15h_power_attr_group = {
114         .attrs  = fam15h_power_attrs,
115 };
116 
117 static bool fam15h_power_is_internal_node0(struct pci_dev *f4)
118 {
119         u32 val;
120 
121         pci_bus_read_config_dword(f4->bus, PCI_DEVFN(PCI_SLOT(f4->devfn), 3),
122                                   REG_NORTHBRIDGE_CAP, &val);
123         if ((val & BIT(29)) && ((val >> 30) & 3))
124                 return false;
125 
126         return true;
127 }
128 
129 /*
130  * Newer BKDG versions have an updated recommendation on how to properly
131  * initialize the running average range (was: 0xE, now: 0x9). This avoids
132  * counter saturations resulting in bogus power readings.
133  * We correct this value ourselves to cope with older BIOSes.
134  */
135 static const struct pci_device_id affected_device[] = {
136         { PCI_VDEVICE(AMD, PCI_DEVICE_ID_AMD_15H_NB_F4) },
137         { 0 }
138 };
139 
140 static void tweak_runavg_range(struct pci_dev *pdev)
141 {
142         u32 val;
143 
144         /*
145          * let this quirk apply only to the current version of the
146          * northbridge, since future versions may change the behavior
147          */
148         if (!pci_match_id(affected_device, pdev))
149                 return;
150 
151         pci_bus_read_config_dword(pdev->bus,
152                 PCI_DEVFN(PCI_SLOT(pdev->devfn), 5),
153                 REG_TDP_RUNNING_AVERAGE, &val);
154         if ((val & 0xf) != 0xe)
155                 return;
156 
157         val &= ~0xf;
158         val |=  0x9;
159         pci_bus_write_config_dword(pdev->bus,
160                 PCI_DEVFN(PCI_SLOT(pdev->devfn), 5),
161                 REG_TDP_RUNNING_AVERAGE, val);
162 }
163 
164 #ifdef CONFIG_PM
165 static int fam15h_power_resume(struct pci_dev *pdev)
166 {
167         tweak_runavg_range(pdev);
168         return 0;
169 }
170 #else
171 #define fam15h_power_resume NULL
172 #endif
173 
174 static void fam15h_power_init_data(struct pci_dev *f4,
175                                              struct fam15h_power_data *data)
176 {
177         u32 val;
178         u64 tmp;
179 
180         pci_read_config_dword(f4, REG_PROCESSOR_TDP, &val);
181         data->base_tdp = val >> 16;
182         tmp = val & 0xffff;
183 
184         pci_bus_read_config_dword(f4->bus, PCI_DEVFN(PCI_SLOT(f4->devfn), 5),
185                                   REG_TDP_LIMIT3, &val);
186 
187         data->tdp_to_watts = ((val & 0x3ff) << 6) | ((val >> 10) & 0x3f);
188         tmp *= data->tdp_to_watts;
189 
190         /* result not allowed to be >= 256W */
191         if ((tmp >> 16) >= 256)
192                 dev_warn(&f4->dev,
193                          "Bogus value for ProcessorPwrWatts (processor_pwr_watts>=%u)\n",
194                          (unsigned int) (tmp >> 16));
195 
196         /* convert to microWatt */
197         data->processor_pwr_watts = (tmp * 15625) >> 10;
198 }
199 
200 static int fam15h_power_probe(struct pci_dev *pdev,
201                                         const struct pci_device_id *id)
202 {
203         struct fam15h_power_data *data;
204         struct device *dev = &pdev->dev;
205         int err;
206 
207         /*
208          * though we ignore every other northbridge, we still have to
209          * do the tweaking on _each_ node in MCM processors as the counters
210          * are working hand-in-hand
211          */
212         tweak_runavg_range(pdev);
213 
214         if (!fam15h_power_is_internal_node0(pdev))
215                 return -ENODEV;
216 
217         data = devm_kzalloc(dev, sizeof(struct fam15h_power_data), GFP_KERNEL);
218         if (!data)
219                 return -ENOMEM;
220 
221         fam15h_power_init_data(pdev, data);
222 
223         dev_set_drvdata(dev, data);
224         err = sysfs_create_group(&dev->kobj, &fam15h_power_attr_group);
225         if (err)
226                 return err;
227 
228         data->hwmon_dev = hwmon_device_register(dev);
229         if (IS_ERR(data->hwmon_dev)) {
230                 err = PTR_ERR(data->hwmon_dev);
231                 goto exit_remove_group;
232         }
233 
234         return 0;
235 
236 exit_remove_group:
237         sysfs_remove_group(&dev->kobj, &fam15h_power_attr_group);
238         return err;
239 }
240 
241 static void fam15h_power_remove(struct pci_dev *pdev)
242 {
243         struct device *dev;
244         struct fam15h_power_data *data;
245 
246         dev = &pdev->dev;
247         data = dev_get_drvdata(dev);
248         hwmon_device_unregister(data->hwmon_dev);
249         sysfs_remove_group(&dev->kobj, &fam15h_power_attr_group);
250 }
251 
252 static const struct pci_device_id fam15h_power_id_table[] = {
253         { PCI_VDEVICE(AMD, PCI_DEVICE_ID_AMD_15H_NB_F4) },
254         { PCI_VDEVICE(AMD, PCI_DEVICE_ID_AMD_16H_NB_F4) },
255         {}
256 };
257 MODULE_DEVICE_TABLE(pci, fam15h_power_id_table);
258 
259 static struct pci_driver fam15h_power_driver = {
260         .name = "fam15h_power",
261         .id_table = fam15h_power_id_table,
262         .probe = fam15h_power_probe,
263         .remove = fam15h_power_remove,
264         .resume = fam15h_power_resume,
265 };
266 
267 module_pci_driver(fam15h_power_driver);
268 

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