summaryrefslogtreecommitdiff
path: root/drivers/hwmon/fam15h_power.c
blob: 6307112c2c0c61528cd5d6af929c7b85144792ba (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
// SPDX-License-Identifier: GPL-2.0-or-later
/*
 * fam15h_power.c - AMD Family 15h processor power monitoring
 *
 * Copyright (c) 2011-2016 Advanced Micro Devices, Inc.
 * Author: Andreas Herrmann <herrmann.der.user@googlemail.com>
 */

#include <linux/err.h>
#include <linux/hwmon.h>
#include <linux/hwmon-sysfs.h>
#include <linux/init.h>
#include <linux/module.h>
#include <linux/pci.h>
#include <linux/bitops.h>
#include <linux/cpu.h>
#include <linux/cpumask.h>
#include <linux/time.h>
#include <linux/sched.h>
#include <linux/topology.h>
#include <asm/processor.h>
#include <asm/msr.h>

MODULE_DESCRIPTION("AMD Family 15h CPU processor power monitor");
MODULE_AUTHOR("Andreas Herrmann <herrmann.der.user@googlemail.com>");
MODULE_LICENSE("GPL");

/* D18F3 */
#define REG_NORTHBRIDGE_CAP		0xe8

/* D18F4 */
#define REG_PROCESSOR_TDP		0x1b8

/* D18F5 */
#define REG_TDP_RUNNING_AVERAGE		0xe0
#define REG_TDP_LIMIT3			0xe8

#define FAM15H_MIN_NUM_ATTRS		2
#define FAM15H_NUM_GROUPS		2
#define MAX_CUS				8

/* set maximum interval as 1 second */
#define MAX_INTERVAL			1000

#define PCI_DEVICE_ID_AMD_15H_M70H_NB_F4 0x15b4

struct fam15h_power_data {
	struct pci_dev *pdev;
	unsigned int tdp_to_watts;
	unsigned int base_tdp;
	unsigned int processor_pwr_watts;
	unsigned int cpu_pwr_sample_ratio;
	const struct attribute_group *groups[FAM15H_NUM_GROUPS];
	struct attribute_group group;
	/* maximum accumulated power of a compute unit */
	u64 max_cu_acc_power;
	/* accumulated power of the compute units */
	u64 cu_acc_power[MAX_CUS];
	/* performance timestamp counter */
	u64 cpu_sw_pwr_ptsc[MAX_CUS];
	/* online/offline status of current compute unit */
	int cu_on[MAX_CUS];
	unsigned long power_period;
};

static bool is_carrizo_or_later(void)
{
	return boot_cpu_data.x86 == 0x15 && boot_cpu_data.x86_model >= 0x60;
}

static ssize_t power1_input_show(struct device *dev,
				 struct device_attribute *attr, char *buf)
{
	u32 val, tdp_limit, running_avg_range;
	s32 running_avg_capture;
	u64 curr_pwr_watts;
	struct fam15h_power_data *data = dev_get_drvdata(dev);
	struct pci_dev *f4 = data->pdev;

	pci_bus_read_config_dword(f4->bus, PCI_DEVFN(PCI_SLOT(f4->devfn), 5),
				  REG_TDP_RUNNING_AVERAGE, &val);

	/*
	 * On Carrizo and later platforms, TdpRunAvgAccCap bit field
	 * is extended to 4:31 from 4:25.
	 */
	if (is_carrizo_or_later()) {
		running_avg_capture = val >> 4;
		running_avg_capture = sign_extend32(running_avg_capture, 27);
	} else {
		running_avg_capture = (val >> 4) & 0x3fffff;
		running_avg_capture = sign_extend32(running_avg_capture, 21);
	}

	running_avg_range = (val & 0xf) + 1;

	pci_bus_read_config_dword(f4->bus, PCI_DEVFN(PCI_SLOT(f4->devfn), 5),
				  REG_TDP_LIMIT3, &val);

	/*
	 * On Carrizo and later platforms, ApmTdpLimit bit field
	 * is extended to 16:31 from 16:28.
	 */
	if (is_carrizo_or_later())
		tdp_limit = val >> 16;
	else
		tdp_limit = (val >> 16) & 0x1fff;

	curr_pwr_watts = ((u64)(tdp_limit +
				data->base_tdp)) << running_avg_range;
	curr_pwr_watts -= running_avg_capture;
	curr_pwr_watts *= data->tdp_to_watts;

	/*
	 * Convert to microWatt
	 *
	 * power is in Watt provided as fixed point integer with
	 * scaling factor 1/(2^16).  For conversion we use
	 * (10^6)/(2^16) = 15625/(2^10)
	 */
	curr_pwr_watts = (curr_pwr_watts * 15625) >> (10 + running_avg_range);
	return sprintf(buf, "%u\n", (unsigned int) curr_pwr_watts);
}
static DEVICE_ATTR_RO(power1_input);

static ssize_t power1_crit_show(struct device *dev,
				struct device_attribute *attr, char *buf)
{
	struct fam15h_power_data *data = dev_get_drvdata(dev);

	return sprintf(buf, "%u\n", data->processor_pwr_watts);
}
static DEVICE_ATTR_RO(power1_crit);

static void do_read_registers_on_cu(void *_data)
{
	struct fam15h_power_data *data = _data;
	int cu;

	/*
	 * With the new x86 topology modelling, cpu core id actually
	 * is compute unit id.
	 */
	cu = topology_core_id(smp_processor_id());

	rdmsrl_safe(MSR_F15H_CU_PWR_ACCUMULATOR, &data->cu_acc_power[cu]);
	rdmsrl_safe(MSR_F15H_PTSC, &data->cpu_sw_pwr_ptsc[cu]);

	data->cu_on[cu] = 1;
}

/*
 * This function is only able to be called when CPUID
 * Fn8000_0007:EDX[12] is set.
 */
static int read_registers(struct fam15h_power_data *data)
{
	int core, this_core;
	cpumask_var_t mask;
	int ret, cpu;

	ret = zalloc_cpumask_var(&mask, GFP_KERNEL);
	if (!ret)
		return -ENOMEM;

	memset(data->cu_on, 0, sizeof(int) * MAX_CUS);

	cpus_read_lock();

	/*
	 * Choose the first online core of each compute unit, and then
	 * read their MSR value of power and ptsc in a single IPI,
	 * because the MSR value of CPU core represent the compute
	 * unit's.
	 */
	core = -1;

	for_each_online_cpu(cpu) {
		this_core = topology_core_id(cpu);

		if (this_core == core)
			continue;

		core = this_core;

		/* get any CPU on this compute unit */
		cpumask_set_cpu(cpumask_any(topology_sibling_cpumask(cpu)), mask);
	}

	on_each_cpu_mask(mask, do_read_registers_on_cu, data, true);

	cpus_read_unlock();
	free_cpumask_var(mask);

	return 0;
}

static ssize_t power1_average_show(struct device *dev,
				   struct device_attribute *attr, char *buf)
{
	struct fam15h_power_data *data = dev_get_drvdata(dev);
	u64 prev_cu_acc_power[MAX_CUS], prev_ptsc[MAX_CUS],
	    jdelta[MAX_CUS];
	u64 tdelta, avg_acc;
	int cu, cu_num, ret;
	signed long leftover;

	/*
	 * With the new x86 topology modelling, x86_max_cores is the
	 * compute unit number.
	 */
	cu_num = boot_cpu_data.x86_max_cores;

	ret = read_registers(data);
	if (ret)
		return 0;

	for (cu = 0; cu < cu_num; cu++) {
		prev_cu_acc_power[cu] = data->cu_acc_power[cu];
		prev_ptsc[cu] = data->cpu_sw_pwr_ptsc[cu];
	}

	leftover = schedule_timeout_interruptible(msecs_to_jiffies(data->power_period));
	if (leftover)
		return 0;

	ret = read_registers(data);
	if (ret)
		return 0;

	for (cu = 0, avg_acc = 0; cu < cu_num; cu++) {
		/* check if current compute unit is online */
		if (data->cu_on[cu] == 0)
			continue;

		if (data->cu_acc_power[cu] < prev_cu_acc_power[cu]) {
			jdelta[cu] = data->max_cu_acc_power + data->cu_acc_power[cu];
			jdelta[cu] -= prev_cu_acc_power[cu];
		} else {
			jdelta[cu] = data->cu_acc_power[cu] - prev_cu_acc_power[cu];
		}
		tdelta = data->cpu_sw_pwr_ptsc[cu] - prev_ptsc[cu];
		jdelta[cu] *= data->cpu_pwr_sample_ratio * 1000;
		do_div(jdelta[cu], tdelta);

		/* the unit is microWatt */
		avg_acc += jdelta[cu];
	}

	return sprintf(buf, "%llu\n", (unsigned long long)avg_acc);
}
static DEVICE_ATTR_RO(power1_average);

static ssize_t power1_average_interval_show(struct device *dev,
					    struct device_attribute *attr,
					    char *buf)
{
	struct fam15h_power_data *data = dev_get_drvdata(dev);

	return sprintf(buf, "%lu\n", data->power_period);
}

static ssize_t power1_average_interval_store(struct device *dev,
					     struct device_attribute *attr,
					     const char *buf, size_t count)
{
	struct fam15h_power_data *data = dev_get_drvdata(dev);
	unsigned long temp;
	int ret;

	ret = kstrtoul(buf, 10, &temp);
	if (ret)
		return ret;

	if (temp > MAX_INTERVAL)
		return -EINVAL;

	/* the interval value should be greater than 0 */
	if (temp <= 0)
		return -EINVAL;

	data->power_period = temp;

	return count;
}
static DEVICE_ATTR_RW(power1_average_interval);

static int fam15h_power_init_attrs(struct pci_dev *pdev,
				   struct fam15h_power_data *data)
{
	int n = FAM15H_MIN_NUM_ATTRS;
	struct attribute **fam15h_power_attrs;
	struct cpuinfo_x86 *c = &boot_cpu_data;

	if (c->x86 == 0x15 &&
	    (c->x86_model <= 0xf ||
	     (c->x86_model >= 0x60 && c->x86_model <= 0x7f)))
		n += 1;

	/* check if processor supports accumulated power */
	if (boot_cpu_has(X86_FEATURE_ACC_POWER))
		n += 2;

	fam15h_power_attrs = devm_kcalloc(&pdev->dev, n,
					  sizeof(*fam15h_power_attrs),
					  GFP_KERNEL);

	if (!fam15h_power_attrs)
		return -ENOMEM;

	n = 0;
	fam15h_power_attrs[n++] = &dev_attr_power1_crit.attr;
	if (c->x86 == 0x15 &&
	    (c->x86_model <= 0xf ||
	     (c->x86_model >= 0x60 && c->x86_model <= 0x7f)))
		fam15h_power_attrs[n++] = &dev_attr_power1_input.attr;

	if (boot_cpu_has(X86_FEATURE_ACC_POWER)) {
		fam15h_power_attrs[n++] = &dev_attr_power1_average.attr;
		fam15h_power_attrs[n++] = &dev_attr_power1_average_interval.attr;
	}

	data->group.attrs = fam15h_power_attrs;

	return 0;
}

static bool should_load_on_this_node(struct pci_dev *f4)
{
	u32 val;

	pci_bus_read_config_dword(f4->bus, PCI_DEVFN(PCI_SLOT(f4->devfn), 3),
				  REG_NORTHBRIDGE_CAP, &val);
	if ((val & BIT(29)) && ((val >> 30) & 3))
		return false;

	return true;
}

/*
 * Newer BKDG versions have an updated recommendation on how to properly
 * initialize the running average range (was: 0xE, now: 0x9). This avoids
 * counter saturations resulting in bogus power readings.
 * We correct this value ourselves to cope with older BIOSes.
 */
static const struct pci_device_id affected_device[] = {
	{ PCI_VDEVICE(AMD, PCI_DEVICE_ID_AMD_15H_NB_F4) },
	{ 0 }
};

static void tweak_runavg_range(struct pci_dev *pdev)
{
	u32 val;

	/*
	 * let this quirk apply only to the current version of the
	 * northbridge, since future versions may change the behavior
	 */
	if (!pci_match_id(affected_device, pdev))
		return;

	pci_bus_read_config_dword(pdev->bus,
		PCI_DEVFN(PCI_SLOT(pdev->devfn), 5),
		REG_TDP_RUNNING_AVERAGE, &val);
	if ((val & 0xf) != 0xe)
		return;

	val &= ~0xf;
	val |=  0x9;
	pci_bus_write_config_dword(pdev->bus,
		PCI_DEVFN(PCI_SLOT(pdev->devfn), 5),
		REG_TDP_RUNNING_AVERAGE, val);
}

#ifdef CONFIG_PM
static int fam15h_power_resume(struct pci_dev *pdev)
{
	tweak_runavg_range(pdev);
	return 0;
}
#else
#define fam15h_power_resume NULL
#endif

static int fam15h_power_init_data(struct pci_dev *f4,
				  struct fam15h_power_data *data)
{
	u32 val;
	u64 tmp;
	int ret;

	pci_read_config_dword(f4, REG_PROCESSOR_TDP, &val);
	data->base_tdp = val >> 16;
	tmp = val & 0xffff;

	pci_bus_read_config_dword(f4->bus, PCI_DEVFN(PCI_SLOT(f4->devfn), 5),
				  REG_TDP_LIMIT3, &val);

	data->tdp_to_watts = ((val & 0x3ff) << 6) | ((val >> 10) & 0x3f);
	tmp *= data->tdp_to_watts;

	/* result not allowed to be >= 256W */
	if ((tmp >> 16) >= 256)
		dev_warn(&f4->dev,
			 "Bogus value for ProcessorPwrWatts (processor_pwr_watts>=%u)\n",
			 (unsigned int) (tmp >> 16));

	/* convert to microWatt */
	data->processor_pwr_watts = (tmp * 15625) >> 10;

	ret = fam15h_power_init_attrs(f4, data);
	if (ret)
		return ret;


	/* CPUID Fn8000_0007:EDX[12] indicates to support accumulated power */
	if (!boot_cpu_has(X86_FEATURE_ACC_POWER))
		return 0;

	/*
	 * determine the ratio of the compute unit power accumulator
	 * sample period to the PTSC counter period by executing CPUID
	 * Fn8000_0007:ECX
	 */
	data->cpu_pwr_sample_ratio = cpuid_ecx(0x80000007);

	if (rdmsrl_safe(MSR_F15H_CU_MAX_PWR_ACCUMULATOR, &tmp)) {
		pr_err("Failed to read max compute unit power accumulator MSR\n");
		return -ENODEV;
	}

	data->max_cu_acc_power = tmp;

	/*
	 * Milliseconds are a reasonable interval for the measurement.
	 * But it shouldn't set too long here, because several seconds
	 * would cause the read function to hang. So set default
	 * interval as 10 ms.
	 */
	data->power_period = 10;

	return read_registers(data);
}

static int fam15h_power_probe(struct pci_dev *pdev,
			      const struct pci_device_id *id)
{
	struct fam15h_power_data *data;
	struct device *dev = &pdev->dev;
	struct device *hwmon_dev;
	int ret;

	/*
	 * though we ignore every other northbridge, we still have to
	 * do the tweaking on _each_ node in MCM processors as the counters
	 * are working hand-in-hand
	 */
	tweak_runavg_range(pdev);

	if (!should_load_on_this_node(pdev))
		return -ENODEV;

	data = devm_kzalloc(dev, sizeof(struct fam15h_power_data), GFP_KERNEL);
	if (!data)
		return -ENOMEM;

	ret = fam15h_power_init_data(pdev, data);
	if (ret)
		return ret;

	data->pdev = pdev;

	data->groups[0] = &data->group;

	hwmon_dev = devm_hwmon_device_register_with_groups(dev, "fam15h_power",
							   data,
							   &data->groups[0]);
	return PTR_ERR_OR_ZERO(hwmon_dev);
}

static const struct pci_device_id fam15h_power_id_table[] = {
	{ PCI_VDEVICE(AMD, PCI_DEVICE_ID_AMD_15H_NB_F4) },
	{ PCI_VDEVICE(AMD, PCI_DEVICE_ID_AMD_15H_M30H_NB_F4) },
	{ PCI_VDEVICE(AMD, PCI_DEVICE_ID_AMD_15H_M60H_NB_F4) },
	{ PCI_VDEVICE(AMD, PCI_DEVICE_ID_AMD_15H_M70H_NB_F4) },
	{ PCI_VDEVICE(AMD, PCI_DEVICE_ID_AMD_16H_NB_F4) },
	{ PCI_VDEVICE(AMD, PCI_DEVICE_ID_AMD_16H_M30H_NB_F4) },
	{}
};
MODULE_DEVICE_TABLE(pci, fam15h_power_id_table);

static struct pci_driver fam15h_power_driver = {
	.name = "fam15h_power",
	.id_table = fam15h_power_id_table,
	.probe = fam15h_power_probe,
	.resume = fam15h_power_resume,
};

module_pci_driver(fam15h_power_driver);