xref: /openbmc/linux/drivers/hwmon/fam15h_power.c (revision 6d99a79c)
1 /*
2  * fam15h_power.c - AMD Family 15h processor power monitoring
3  *
4  * Copyright (c) 2011-2016 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 <linux/cpu.h>
29 #include <linux/cpumask.h>
30 #include <linux/time.h>
31 #include <linux/sched.h>
32 #include <asm/processor.h>
33 #include <asm/msr.h>
34 
35 MODULE_DESCRIPTION("AMD Family 15h CPU processor power monitor");
36 MODULE_AUTHOR("Andreas Herrmann <herrmann.der.user@googlemail.com>");
37 MODULE_LICENSE("GPL");
38 
39 /* D18F3 */
40 #define REG_NORTHBRIDGE_CAP		0xe8
41 
42 /* D18F4 */
43 #define REG_PROCESSOR_TDP		0x1b8
44 
45 /* D18F5 */
46 #define REG_TDP_RUNNING_AVERAGE		0xe0
47 #define REG_TDP_LIMIT3			0xe8
48 
49 #define FAM15H_MIN_NUM_ATTRS		2
50 #define FAM15H_NUM_GROUPS		2
51 #define MAX_CUS				8
52 
53 /* set maximum interval as 1 second */
54 #define MAX_INTERVAL			1000
55 
56 #define MSR_F15H_CU_PWR_ACCUMULATOR	0xc001007a
57 #define MSR_F15H_CU_MAX_PWR_ACCUMULATOR	0xc001007b
58 #define MSR_F15H_PTSC			0xc0010280
59 
60 #define PCI_DEVICE_ID_AMD_15H_M70H_NB_F4 0x15b4
61 
62 struct fam15h_power_data {
63 	struct pci_dev *pdev;
64 	unsigned int tdp_to_watts;
65 	unsigned int base_tdp;
66 	unsigned int processor_pwr_watts;
67 	unsigned int cpu_pwr_sample_ratio;
68 	const struct attribute_group *groups[FAM15H_NUM_GROUPS];
69 	struct attribute_group group;
70 	/* maximum accumulated power of a compute unit */
71 	u64 max_cu_acc_power;
72 	/* accumulated power of the compute units */
73 	u64 cu_acc_power[MAX_CUS];
74 	/* performance timestamp counter */
75 	u64 cpu_sw_pwr_ptsc[MAX_CUS];
76 	/* online/offline status of current compute unit */
77 	int cu_on[MAX_CUS];
78 	unsigned long power_period;
79 };
80 
81 static bool is_carrizo_or_later(void)
82 {
83 	return boot_cpu_data.x86 == 0x15 && boot_cpu_data.x86_model >= 0x60;
84 }
85 
86 static ssize_t power1_input_show(struct device *dev,
87 				 struct device_attribute *attr, char *buf)
88 {
89 	u32 val, tdp_limit, running_avg_range;
90 	s32 running_avg_capture;
91 	u64 curr_pwr_watts;
92 	struct fam15h_power_data *data = dev_get_drvdata(dev);
93 	struct pci_dev *f4 = data->pdev;
94 
95 	pci_bus_read_config_dword(f4->bus, PCI_DEVFN(PCI_SLOT(f4->devfn), 5),
96 				  REG_TDP_RUNNING_AVERAGE, &val);
97 
98 	/*
99 	 * On Carrizo and later platforms, TdpRunAvgAccCap bit field
100 	 * is extended to 4:31 from 4:25.
101 	 */
102 	if (is_carrizo_or_later()) {
103 		running_avg_capture = val >> 4;
104 		running_avg_capture = sign_extend32(running_avg_capture, 27);
105 	} else {
106 		running_avg_capture = (val >> 4) & 0x3fffff;
107 		running_avg_capture = sign_extend32(running_avg_capture, 21);
108 	}
109 
110 	running_avg_range = (val & 0xf) + 1;
111 
112 	pci_bus_read_config_dword(f4->bus, PCI_DEVFN(PCI_SLOT(f4->devfn), 5),
113 				  REG_TDP_LIMIT3, &val);
114 
115 	/*
116 	 * On Carrizo and later platforms, ApmTdpLimit bit field
117 	 * is extended to 16:31 from 16:28.
118 	 */
119 	if (is_carrizo_or_later())
120 		tdp_limit = val >> 16;
121 	else
122 		tdp_limit = (val >> 16) & 0x1fff;
123 
124 	curr_pwr_watts = ((u64)(tdp_limit +
125 				data->base_tdp)) << running_avg_range;
126 	curr_pwr_watts -= running_avg_capture;
127 	curr_pwr_watts *= data->tdp_to_watts;
128 
129 	/*
130 	 * Convert to microWatt
131 	 *
132 	 * power is in Watt provided as fixed point integer with
133 	 * scaling factor 1/(2^16).  For conversion we use
134 	 * (10^6)/(2^16) = 15625/(2^10)
135 	 */
136 	curr_pwr_watts = (curr_pwr_watts * 15625) >> (10 + running_avg_range);
137 	return sprintf(buf, "%u\n", (unsigned int) curr_pwr_watts);
138 }
139 static DEVICE_ATTR_RO(power1_input);
140 
141 static ssize_t power1_crit_show(struct device *dev,
142 				struct device_attribute *attr, char *buf)
143 {
144 	struct fam15h_power_data *data = dev_get_drvdata(dev);
145 
146 	return sprintf(buf, "%u\n", data->processor_pwr_watts);
147 }
148 static DEVICE_ATTR_RO(power1_crit);
149 
150 static void do_read_registers_on_cu(void *_data)
151 {
152 	struct fam15h_power_data *data = _data;
153 	int cpu, cu;
154 
155 	cpu = smp_processor_id();
156 
157 	/*
158 	 * With the new x86 topology modelling, cpu core id actually
159 	 * is compute unit id.
160 	 */
161 	cu = cpu_data(cpu).cpu_core_id;
162 
163 	rdmsrl_safe(MSR_F15H_CU_PWR_ACCUMULATOR, &data->cu_acc_power[cu]);
164 	rdmsrl_safe(MSR_F15H_PTSC, &data->cpu_sw_pwr_ptsc[cu]);
165 
166 	data->cu_on[cu] = 1;
167 }
168 
169 /*
170  * This function is only able to be called when CPUID
171  * Fn8000_0007:EDX[12] is set.
172  */
173 static int read_registers(struct fam15h_power_data *data)
174 {
175 	int core, this_core;
176 	cpumask_var_t mask;
177 	int ret, cpu;
178 
179 	ret = zalloc_cpumask_var(&mask, GFP_KERNEL);
180 	if (!ret)
181 		return -ENOMEM;
182 
183 	memset(data->cu_on, 0, sizeof(int) * MAX_CUS);
184 
185 	get_online_cpus();
186 
187 	/*
188 	 * Choose the first online core of each compute unit, and then
189 	 * read their MSR value of power and ptsc in a single IPI,
190 	 * because the MSR value of CPU core represent the compute
191 	 * unit's.
192 	 */
193 	core = -1;
194 
195 	for_each_online_cpu(cpu) {
196 		this_core = topology_core_id(cpu);
197 
198 		if (this_core == core)
199 			continue;
200 
201 		core = this_core;
202 
203 		/* get any CPU on this compute unit */
204 		cpumask_set_cpu(cpumask_any(topology_sibling_cpumask(cpu)), mask);
205 	}
206 
207 	on_each_cpu_mask(mask, do_read_registers_on_cu, data, true);
208 
209 	put_online_cpus();
210 	free_cpumask_var(mask);
211 
212 	return 0;
213 }
214 
215 static ssize_t power1_average_show(struct device *dev,
216 				   struct device_attribute *attr, char *buf)
217 {
218 	struct fam15h_power_data *data = dev_get_drvdata(dev);
219 	u64 prev_cu_acc_power[MAX_CUS], prev_ptsc[MAX_CUS],
220 	    jdelta[MAX_CUS];
221 	u64 tdelta, avg_acc;
222 	int cu, cu_num, ret;
223 	signed long leftover;
224 
225 	/*
226 	 * With the new x86 topology modelling, x86_max_cores is the
227 	 * compute unit number.
228 	 */
229 	cu_num = boot_cpu_data.x86_max_cores;
230 
231 	ret = read_registers(data);
232 	if (ret)
233 		return 0;
234 
235 	for (cu = 0; cu < cu_num; cu++) {
236 		prev_cu_acc_power[cu] = data->cu_acc_power[cu];
237 		prev_ptsc[cu] = data->cpu_sw_pwr_ptsc[cu];
238 	}
239 
240 	leftover = schedule_timeout_interruptible(msecs_to_jiffies(data->power_period));
241 	if (leftover)
242 		return 0;
243 
244 	ret = read_registers(data);
245 	if (ret)
246 		return 0;
247 
248 	for (cu = 0, avg_acc = 0; cu < cu_num; cu++) {
249 		/* check if current compute unit is online */
250 		if (data->cu_on[cu] == 0)
251 			continue;
252 
253 		if (data->cu_acc_power[cu] < prev_cu_acc_power[cu]) {
254 			jdelta[cu] = data->max_cu_acc_power + data->cu_acc_power[cu];
255 			jdelta[cu] -= prev_cu_acc_power[cu];
256 		} else {
257 			jdelta[cu] = data->cu_acc_power[cu] - prev_cu_acc_power[cu];
258 		}
259 		tdelta = data->cpu_sw_pwr_ptsc[cu] - prev_ptsc[cu];
260 		jdelta[cu] *= data->cpu_pwr_sample_ratio * 1000;
261 		do_div(jdelta[cu], tdelta);
262 
263 		/* the unit is microWatt */
264 		avg_acc += jdelta[cu];
265 	}
266 
267 	return sprintf(buf, "%llu\n", (unsigned long long)avg_acc);
268 }
269 static DEVICE_ATTR_RO(power1_average);
270 
271 static ssize_t power1_average_interval_show(struct device *dev,
272 					    struct device_attribute *attr,
273 					    char *buf)
274 {
275 	struct fam15h_power_data *data = dev_get_drvdata(dev);
276 
277 	return sprintf(buf, "%lu\n", data->power_period);
278 }
279 
280 static ssize_t power1_average_interval_store(struct device *dev,
281 					     struct device_attribute *attr,
282 					     const char *buf, size_t count)
283 {
284 	struct fam15h_power_data *data = dev_get_drvdata(dev);
285 	unsigned long temp;
286 	int ret;
287 
288 	ret = kstrtoul(buf, 10, &temp);
289 	if (ret)
290 		return ret;
291 
292 	if (temp > MAX_INTERVAL)
293 		return -EINVAL;
294 
295 	/* the interval value should be greater than 0 */
296 	if (temp <= 0)
297 		return -EINVAL;
298 
299 	data->power_period = temp;
300 
301 	return count;
302 }
303 static DEVICE_ATTR_RW(power1_average_interval);
304 
305 static int fam15h_power_init_attrs(struct pci_dev *pdev,
306 				   struct fam15h_power_data *data)
307 {
308 	int n = FAM15H_MIN_NUM_ATTRS;
309 	struct attribute **fam15h_power_attrs;
310 	struct cpuinfo_x86 *c = &boot_cpu_data;
311 
312 	if (c->x86 == 0x15 &&
313 	    (c->x86_model <= 0xf ||
314 	     (c->x86_model >= 0x60 && c->x86_model <= 0x7f)))
315 		n += 1;
316 
317 	/* check if processor supports accumulated power */
318 	if (boot_cpu_has(X86_FEATURE_ACC_POWER))
319 		n += 2;
320 
321 	fam15h_power_attrs = devm_kcalloc(&pdev->dev, n,
322 					  sizeof(*fam15h_power_attrs),
323 					  GFP_KERNEL);
324 
325 	if (!fam15h_power_attrs)
326 		return -ENOMEM;
327 
328 	n = 0;
329 	fam15h_power_attrs[n++] = &dev_attr_power1_crit.attr;
330 	if (c->x86 == 0x15 &&
331 	    (c->x86_model <= 0xf ||
332 	     (c->x86_model >= 0x60 && c->x86_model <= 0x7f)))
333 		fam15h_power_attrs[n++] = &dev_attr_power1_input.attr;
334 
335 	if (boot_cpu_has(X86_FEATURE_ACC_POWER)) {
336 		fam15h_power_attrs[n++] = &dev_attr_power1_average.attr;
337 		fam15h_power_attrs[n++] = &dev_attr_power1_average_interval.attr;
338 	}
339 
340 	data->group.attrs = fam15h_power_attrs;
341 
342 	return 0;
343 }
344 
345 static bool should_load_on_this_node(struct pci_dev *f4)
346 {
347 	u32 val;
348 
349 	pci_bus_read_config_dword(f4->bus, PCI_DEVFN(PCI_SLOT(f4->devfn), 3),
350 				  REG_NORTHBRIDGE_CAP, &val);
351 	if ((val & BIT(29)) && ((val >> 30) & 3))
352 		return false;
353 
354 	return true;
355 }
356 
357 /*
358  * Newer BKDG versions have an updated recommendation on how to properly
359  * initialize the running average range (was: 0xE, now: 0x9). This avoids
360  * counter saturations resulting in bogus power readings.
361  * We correct this value ourselves to cope with older BIOSes.
362  */
363 static const struct pci_device_id affected_device[] = {
364 	{ PCI_VDEVICE(AMD, PCI_DEVICE_ID_AMD_15H_NB_F4) },
365 	{ 0 }
366 };
367 
368 static void tweak_runavg_range(struct pci_dev *pdev)
369 {
370 	u32 val;
371 
372 	/*
373 	 * let this quirk apply only to the current version of the
374 	 * northbridge, since future versions may change the behavior
375 	 */
376 	if (!pci_match_id(affected_device, pdev))
377 		return;
378 
379 	pci_bus_read_config_dword(pdev->bus,
380 		PCI_DEVFN(PCI_SLOT(pdev->devfn), 5),
381 		REG_TDP_RUNNING_AVERAGE, &val);
382 	if ((val & 0xf) != 0xe)
383 		return;
384 
385 	val &= ~0xf;
386 	val |=  0x9;
387 	pci_bus_write_config_dword(pdev->bus,
388 		PCI_DEVFN(PCI_SLOT(pdev->devfn), 5),
389 		REG_TDP_RUNNING_AVERAGE, val);
390 }
391 
392 #ifdef CONFIG_PM
393 static int fam15h_power_resume(struct pci_dev *pdev)
394 {
395 	tweak_runavg_range(pdev);
396 	return 0;
397 }
398 #else
399 #define fam15h_power_resume NULL
400 #endif
401 
402 static int fam15h_power_init_data(struct pci_dev *f4,
403 				  struct fam15h_power_data *data)
404 {
405 	u32 val;
406 	u64 tmp;
407 	int ret;
408 
409 	pci_read_config_dword(f4, REG_PROCESSOR_TDP, &val);
410 	data->base_tdp = val >> 16;
411 	tmp = val & 0xffff;
412 
413 	pci_bus_read_config_dword(f4->bus, PCI_DEVFN(PCI_SLOT(f4->devfn), 5),
414 				  REG_TDP_LIMIT3, &val);
415 
416 	data->tdp_to_watts = ((val & 0x3ff) << 6) | ((val >> 10) & 0x3f);
417 	tmp *= data->tdp_to_watts;
418 
419 	/* result not allowed to be >= 256W */
420 	if ((tmp >> 16) >= 256)
421 		dev_warn(&f4->dev,
422 			 "Bogus value for ProcessorPwrWatts (processor_pwr_watts>=%u)\n",
423 			 (unsigned int) (tmp >> 16));
424 
425 	/* convert to microWatt */
426 	data->processor_pwr_watts = (tmp * 15625) >> 10;
427 
428 	ret = fam15h_power_init_attrs(f4, data);
429 	if (ret)
430 		return ret;
431 
432 
433 	/* CPUID Fn8000_0007:EDX[12] indicates to support accumulated power */
434 	if (!boot_cpu_has(X86_FEATURE_ACC_POWER))
435 		return 0;
436 
437 	/*
438 	 * determine the ratio of the compute unit power accumulator
439 	 * sample period to the PTSC counter period by executing CPUID
440 	 * Fn8000_0007:ECX
441 	 */
442 	data->cpu_pwr_sample_ratio = cpuid_ecx(0x80000007);
443 
444 	if (rdmsrl_safe(MSR_F15H_CU_MAX_PWR_ACCUMULATOR, &tmp)) {
445 		pr_err("Failed to read max compute unit power accumulator MSR\n");
446 		return -ENODEV;
447 	}
448 
449 	data->max_cu_acc_power = tmp;
450 
451 	/*
452 	 * Milliseconds are a reasonable interval for the measurement.
453 	 * But it shouldn't set too long here, because several seconds
454 	 * would cause the read function to hang. So set default
455 	 * interval as 10 ms.
456 	 */
457 	data->power_period = 10;
458 
459 	return read_registers(data);
460 }
461 
462 static int fam15h_power_probe(struct pci_dev *pdev,
463 			      const struct pci_device_id *id)
464 {
465 	struct fam15h_power_data *data;
466 	struct device *dev = &pdev->dev;
467 	struct device *hwmon_dev;
468 	int ret;
469 
470 	/*
471 	 * though we ignore every other northbridge, we still have to
472 	 * do the tweaking on _each_ node in MCM processors as the counters
473 	 * are working hand-in-hand
474 	 */
475 	tweak_runavg_range(pdev);
476 
477 	if (!should_load_on_this_node(pdev))
478 		return -ENODEV;
479 
480 	data = devm_kzalloc(dev, sizeof(struct fam15h_power_data), GFP_KERNEL);
481 	if (!data)
482 		return -ENOMEM;
483 
484 	ret = fam15h_power_init_data(pdev, data);
485 	if (ret)
486 		return ret;
487 
488 	data->pdev = pdev;
489 
490 	data->groups[0] = &data->group;
491 
492 	hwmon_dev = devm_hwmon_device_register_with_groups(dev, "fam15h_power",
493 							   data,
494 							   &data->groups[0]);
495 	return PTR_ERR_OR_ZERO(hwmon_dev);
496 }
497 
498 static const struct pci_device_id fam15h_power_id_table[] = {
499 	{ PCI_VDEVICE(AMD, PCI_DEVICE_ID_AMD_15H_NB_F4) },
500 	{ PCI_VDEVICE(AMD, PCI_DEVICE_ID_AMD_15H_M30H_NB_F4) },
501 	{ PCI_VDEVICE(AMD, PCI_DEVICE_ID_AMD_15H_M60H_NB_F4) },
502 	{ PCI_VDEVICE(AMD, PCI_DEVICE_ID_AMD_15H_M70H_NB_F4) },
503 	{ PCI_VDEVICE(AMD, PCI_DEVICE_ID_AMD_16H_NB_F4) },
504 	{ PCI_VDEVICE(AMD, PCI_DEVICE_ID_AMD_16H_M30H_NB_F4) },
505 	{}
506 };
507 MODULE_DEVICE_TABLE(pci, fam15h_power_id_table);
508 
509 static struct pci_driver fam15h_power_driver = {
510 	.name = "fam15h_power",
511 	.id_table = fam15h_power_id_table,
512 	.probe = fam15h_power_probe,
513 	.resume = fam15h_power_resume,
514 };
515 
516 module_pci_driver(fam15h_power_driver);
517