xref: /linux/drivers/cpufreq/amd-pstate.c (revision 23b5d045ae5df0a2d509915cedcd82f93261d7bc)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * amd-pstate.c - AMD Processor P-state Frequency Driver
4  *
5  * Copyright (C) 2021 Advanced Micro Devices, Inc. All Rights Reserved.
6  *
7  * Author: Huang Rui <ray.huang@amd.com>
8  *
9  * AMD P-State introduces a new CPU performance scaling design for AMD
10  * processors using the ACPI Collaborative Performance and Power Control (CPPC)
11  * feature which works with the AMD SMU firmware providing a finer grained
12  * frequency control range. It is to replace the legacy ACPI P-States control,
13  * allows a flexible, low-latency interface for the Linux kernel to directly
14  * communicate the performance hints to hardware.
15  *
16  * AMD P-State is supported on recent AMD Zen base CPU series include some of
17  * Zen2 and Zen3 processors. _CPC needs to be present in the ACPI tables of AMD
18  * P-State supported system. And there are two types of hardware implementations
19  * for AMD P-State: 1) Full MSR Solution and 2) Shared Memory Solution.
20  * X86_FEATURE_CPPC CPU feature flag is used to distinguish the different types.
21  */
22 
23 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
24 
25 #include <linux/bitfield.h>
26 #include <linux/kernel.h>
27 #include <linux/module.h>
28 #include <linux/init.h>
29 #include <linux/smp.h>
30 #include <linux/sched.h>
31 #include <linux/cpufreq.h>
32 #include <linux/compiler.h>
33 #include <linux/dmi.h>
34 #include <linux/slab.h>
35 #include <linux/acpi.h>
36 #include <linux/io.h>
37 #include <linux/delay.h>
38 #include <linux/uaccess.h>
39 #include <linux/power_supply.h>
40 #include <linux/static_call.h>
41 #include <linux/topology.h>
42 
43 #include <acpi/processor.h>
44 #include <acpi/cppc_acpi.h>
45 
46 #include <asm/msr.h>
47 #include <asm/processor.h>
48 #include <asm/cpufeature.h>
49 #include <asm/cpu_device_id.h>
50 
51 #include "amd-pstate.h"
52 #include "amd-pstate-trace.h"
53 
54 #define AMD_PSTATE_TRANSITION_LATENCY	20000
55 #define AMD_PSTATE_TRANSITION_DELAY	1000
56 #define AMD_PSTATE_FAST_CPPC_TRANSITION_DELAY 600
57 
58 #define AMD_CPPC_EPP_PERFORMANCE		0x00
59 #define AMD_CPPC_EPP_BALANCE_PERFORMANCE	0x80
60 #define AMD_CPPC_EPP_BALANCE_POWERSAVE		0xBF
61 #define AMD_CPPC_EPP_POWERSAVE			0xFF
62 
63 static const char * const amd_pstate_mode_string[] = {
64 	[AMD_PSTATE_UNDEFINED]   = "undefined",
65 	[AMD_PSTATE_DISABLE]     = "disable",
66 	[AMD_PSTATE_PASSIVE]     = "passive",
67 	[AMD_PSTATE_ACTIVE]      = "active",
68 	[AMD_PSTATE_GUIDED]      = "guided",
69 };
70 static_assert(ARRAY_SIZE(amd_pstate_mode_string) == AMD_PSTATE_MAX);
71 
72 const char *amd_pstate_get_mode_string(enum amd_pstate_mode mode)
73 {
74 	if (mode < AMD_PSTATE_UNDEFINED || mode >= AMD_PSTATE_MAX)
75 		mode = AMD_PSTATE_UNDEFINED;
76 	return amd_pstate_mode_string[mode];
77 }
78 EXPORT_SYMBOL_GPL(amd_pstate_get_mode_string);
79 
80 struct quirk_entry {
81 	u32 nominal_freq;
82 	u32 lowest_freq;
83 };
84 
85 static struct cpufreq_driver *current_pstate_driver;
86 static struct cpufreq_driver amd_pstate_driver;
87 static struct cpufreq_driver amd_pstate_epp_driver;
88 static int cppc_state = AMD_PSTATE_UNDEFINED;
89 static bool amd_pstate_prefcore = true;
90 static bool dynamic_epp;
91 static struct quirk_entry *quirks;
92 
93 /*
94  * AMD Energy Preference Performance (EPP)
95  * The EPP is used in the CCLK DPM controller to drive
96  * the frequency that a core is going to operate during
97  * short periods of activity. EPP values will be utilized for
98  * different OS profiles (balanced, performance, power savings)
99  * display strings corresponding to EPP index in the
100  * energy_perf_strings[]
101  *	index		String
102  *-------------------------------------
103  *	0		default
104  *	1		performance
105  *	2		balance_performance
106  *	3		balance_power
107  *	4		power
108  *	5		custom (for raw EPP values)
109  */
110 enum energy_perf_value_index {
111 	EPP_INDEX_DEFAULT = 0,
112 	EPP_INDEX_PERFORMANCE,
113 	EPP_INDEX_BALANCE_PERFORMANCE,
114 	EPP_INDEX_BALANCE_POWERSAVE,
115 	EPP_INDEX_POWERSAVE,
116 	EPP_INDEX_CUSTOM,
117 	EPP_INDEX_MAX,
118 };
119 
120 static const char * const energy_perf_strings[] = {
121 	[EPP_INDEX_DEFAULT] = "default",
122 	[EPP_INDEX_PERFORMANCE] = "performance",
123 	[EPP_INDEX_BALANCE_PERFORMANCE] = "balance_performance",
124 	[EPP_INDEX_BALANCE_POWERSAVE] = "balance_power",
125 	[EPP_INDEX_POWERSAVE] = "power",
126 	[EPP_INDEX_CUSTOM] = "custom",
127 };
128 static_assert(ARRAY_SIZE(energy_perf_strings) == EPP_INDEX_MAX);
129 
130 static unsigned int epp_values[] = {
131 	[EPP_INDEX_DEFAULT] = 0,
132 	[EPP_INDEX_PERFORMANCE] = AMD_CPPC_EPP_PERFORMANCE,
133 	[EPP_INDEX_BALANCE_PERFORMANCE] = AMD_CPPC_EPP_BALANCE_PERFORMANCE,
134 	[EPP_INDEX_BALANCE_POWERSAVE] = AMD_CPPC_EPP_BALANCE_POWERSAVE,
135 	[EPP_INDEX_POWERSAVE] = AMD_CPPC_EPP_POWERSAVE,
136 };
137 static_assert(ARRAY_SIZE(epp_values) == EPP_INDEX_MAX - 1);
138 
139 typedef int (*cppc_mode_transition_fn)(int);
140 
141 static struct quirk_entry quirk_amd_7k62 = {
142 	.nominal_freq = 2600,
143 	.lowest_freq = 550,
144 };
145 
146 static inline u8 freq_to_perf(union perf_cached perf, u32 nominal_freq, unsigned int freq_val)
147 {
148 	u32 perf_val = DIV_ROUND_UP_ULL((u64)freq_val * perf.nominal_perf, nominal_freq);
149 
150 	return (u8)clamp(perf_val, perf.lowest_perf, perf.highest_perf);
151 }
152 
153 static inline u32 perf_to_freq(union perf_cached perf, u32 nominal_freq, u8 perf_val)
154 {
155 	return DIV_ROUND_UP_ULL((u64)nominal_freq * perf_val,
156 				perf.nominal_perf);
157 }
158 
159 static int __init dmi_matched_7k62_bios_bug(const struct dmi_system_id *dmi)
160 {
161 	/**
162 	 * match the broken bios for family 17h processor support CPPC V2
163 	 * broken BIOS lack of nominal_freq and lowest_freq capabilities
164 	 * definition in ACPI tables
165 	 */
166 	if (cpu_feature_enabled(X86_FEATURE_ZEN2)) {
167 		quirks = dmi->driver_data;
168 		pr_info("Overriding nominal and lowest frequencies for %s\n", dmi->ident);
169 		return 1;
170 	}
171 
172 	return 0;
173 }
174 
175 static const struct dmi_system_id amd_pstate_quirks_table[] __initconst = {
176 	{
177 		.callback = dmi_matched_7k62_bios_bug,
178 		.ident = "AMD EPYC 7K62",
179 		.matches = {
180 			DMI_MATCH(DMI_BIOS_VERSION, "5.14"),
181 			DMI_MATCH(DMI_BIOS_RELEASE, "12/12/2019"),
182 		},
183 		.driver_data = &quirk_amd_7k62,
184 	},
185 	{}
186 };
187 MODULE_DEVICE_TABLE(dmi, amd_pstate_quirks_table);
188 
189 static inline int get_mode_idx_from_str(const char *str, size_t size)
190 {
191 	int i;
192 
193 	for (i = 0; i < AMD_PSTATE_MAX; i++) {
194 		if (!strncmp(str, amd_pstate_mode_string[i], size))
195 			return i;
196 	}
197 	return -EINVAL;
198 }
199 
200 static DEFINE_MUTEX(amd_pstate_driver_lock);
201 
202 static u8 msr_get_epp(struct amd_cpudata *cpudata)
203 {
204 	u64 value;
205 	int ret;
206 
207 	ret = rdmsrq_on_cpu(cpudata->cpu, MSR_AMD_CPPC_REQ, &value);
208 	if (ret < 0) {
209 		pr_debug("Could not retrieve energy perf value (%d)\n", ret);
210 		return ret;
211 	}
212 
213 	return FIELD_GET(AMD_CPPC_EPP_PERF_MASK, value);
214 }
215 
216 DEFINE_STATIC_CALL(amd_pstate_get_epp, msr_get_epp);
217 
218 static inline s16 amd_pstate_get_epp(struct amd_cpudata *cpudata)
219 {
220 	return static_call(amd_pstate_get_epp)(cpudata);
221 }
222 
223 static u8 shmem_get_epp(struct amd_cpudata *cpudata)
224 {
225 	u64 epp;
226 	int ret;
227 
228 	ret = cppc_get_epp_perf(cpudata->cpu, &epp);
229 	if (ret < 0) {
230 		pr_debug("Could not retrieve energy perf value (%d)\n", ret);
231 		return ret;
232 	}
233 
234 	return FIELD_GET(AMD_CPPC_EPP_PERF_MASK, epp);
235 }
236 
237 static int msr_update_perf(struct cpufreq_policy *policy, u8 min_perf,
238 			   u8 des_perf, u8 max_perf, u8 epp, bool fast_switch)
239 {
240 	struct amd_cpudata *cpudata = policy->driver_data;
241 	u64 value, prev;
242 
243 	value = prev = READ_ONCE(cpudata->cppc_req_cached);
244 
245 	FIELD_MODIFY(AMD_CPPC_MAX_PERF_MASK, &value, max_perf);
246 	FIELD_MODIFY(AMD_CPPC_DES_PERF_MASK, &value, des_perf);
247 	FIELD_MODIFY(AMD_CPPC_MIN_PERF_MASK, &value, min_perf);
248 	FIELD_MODIFY(AMD_CPPC_EPP_PERF_MASK, &value, epp);
249 
250 	if (trace_amd_pstate_epp_perf_enabled()) {
251 		union perf_cached perf = READ_ONCE(cpudata->perf);
252 
253 		trace_call__amd_pstate_epp_perf(cpudata->cpu,
254 					  perf.highest_perf,
255 					  epp,
256 					  min_perf,
257 					  max_perf,
258 					  policy->boost_enabled,
259 					  value != prev);
260 	}
261 
262 	if (value == prev)
263 		return 0;
264 
265 	if (fast_switch) {
266 		wrmsrq(MSR_AMD_CPPC_REQ, value);
267 	} else {
268 		int ret = wrmsrq_on_cpu(cpudata->cpu, MSR_AMD_CPPC_REQ, value);
269 
270 		if (ret)
271 			return ret;
272 	}
273 
274 	WRITE_ONCE(cpudata->cppc_req_cached, value);
275 
276 	return 0;
277 }
278 
279 DEFINE_STATIC_CALL(amd_pstate_update_perf, msr_update_perf);
280 
281 static inline int amd_pstate_update_perf(struct cpufreq_policy *policy,
282 					  u8 min_perf, u8 des_perf,
283 					  u8 max_perf, u8 epp,
284 					  bool fast_switch)
285 {
286 	return static_call(amd_pstate_update_perf)(policy, min_perf, des_perf,
287 						   max_perf, epp, fast_switch);
288 }
289 
290 static int msr_set_epp(struct cpufreq_policy *policy, u8 epp)
291 {
292 	struct amd_cpudata *cpudata = policy->driver_data;
293 	u64 value, prev;
294 	int ret;
295 
296 	value = prev = READ_ONCE(cpudata->cppc_req_cached);
297 	FIELD_MODIFY(AMD_CPPC_EPP_PERF_MASK, &value, epp);
298 
299 	if (trace_amd_pstate_epp_perf_enabled()) {
300 		union perf_cached perf = cpudata->perf;
301 
302 		trace_call__amd_pstate_epp_perf(cpudata->cpu, perf.highest_perf,
303 					  epp,
304 					  FIELD_GET(AMD_CPPC_MIN_PERF_MASK,
305 						    cpudata->cppc_req_cached),
306 					  FIELD_GET(AMD_CPPC_MAX_PERF_MASK,
307 						    cpudata->cppc_req_cached),
308 					  policy->boost_enabled,
309 					  value != prev);
310 	}
311 
312 	if (value == prev)
313 		return 0;
314 
315 	ret = wrmsrq_on_cpu(cpudata->cpu, MSR_AMD_CPPC_REQ, value);
316 	if (ret) {
317 		pr_err("failed to set energy perf value (%d)\n", ret);
318 		return ret;
319 	}
320 
321 	/* update both so that msr_update_perf() can effectively check */
322 	WRITE_ONCE(cpudata->cppc_req_cached, value);
323 
324 	return ret;
325 }
326 
327 DEFINE_STATIC_CALL(amd_pstate_set_epp, msr_set_epp);
328 
329 static inline int amd_pstate_set_epp(struct cpufreq_policy *policy, u8 epp)
330 {
331 	return static_call(amd_pstate_set_epp)(policy, epp);
332 }
333 
334 static int amd_pstate_set_floor_perf(struct cpufreq_policy *policy, u8 perf)
335 {
336 	struct amd_cpudata *cpudata = policy->driver_data;
337 	u64 value, prev;
338 	bool changed;
339 	int ret;
340 
341 	if (!cpu_feature_enabled(X86_FEATURE_CPPC_PERF_PRIO))
342 		return 0;
343 
344 	value = prev = READ_ONCE(cpudata->cppc_req2_cached);
345 	FIELD_MODIFY(AMD_CPPC_FLOOR_PERF_MASK, &value, perf);
346 
347 	changed = value != prev;
348 	if (!changed) {
349 		ret = 0;
350 		goto out_trace;
351 	}
352 
353 	ret = wrmsrq_on_cpu(cpudata->cpu, MSR_AMD_CPPC_REQ2, value);
354 	if (ret) {
355 		changed = false;
356 		pr_err("failed to set CPPC REQ2 value. Error (%d)\n", ret);
357 		goto out_trace;
358 	}
359 
360 	WRITE_ONCE(cpudata->cppc_req2_cached, value);
361 
362 out_trace:
363 	if (trace_amd_pstate_cppc_req2_enabled())
364 		trace_call__amd_pstate_cppc_req2(cpudata->cpu, perf, changed,
365 						 ret);
366 	return ret;
367 }
368 
369 static int amd_pstate_init_floor_perf(struct cpufreq_policy *policy)
370 {
371 	struct amd_cpudata *cpudata = policy->driver_data;
372 	u8 floor_perf;
373 	u64 value;
374 	int ret;
375 
376 	if (!cpu_feature_enabled(X86_FEATURE_CPPC_PERF_PRIO))
377 		return 0;
378 
379 	ret = rdmsrq_on_cpu(cpudata->cpu, MSR_AMD_CPPC_REQ2, &value);
380 	if (ret) {
381 		pr_err("failed to read CPPC REQ2 value. Error (%d)\n", ret);
382 		return ret;
383 	}
384 
385 	WRITE_ONCE(cpudata->cppc_req2_cached, value);
386 	floor_perf = FIELD_GET(AMD_CPPC_FLOOR_PERF_MASK,
387 			       cpudata->cppc_req2_cached);
388 
389 	/* Set a sane value for floor_perf if the default value is invalid */
390 	if (floor_perf < cpudata->perf.lowest_perf) {
391 		floor_perf = cpudata->perf.nominal_perf;
392 		ret = amd_pstate_set_floor_perf(policy, floor_perf);
393 		if (ret)
394 			return ret;
395 	}
396 
397 
398 	cpudata->bios_floor_perf = floor_perf;
399 	cpudata->floor_freq = perf_to_freq(cpudata->perf, cpudata->nominal_freq,
400 					   floor_perf);
401 	return 0;
402 }
403 
404 static int shmem_set_epp(struct cpufreq_policy *policy, u8 epp)
405 {
406 	struct amd_cpudata *cpudata = policy->driver_data;
407 	struct cppc_perf_ctrls perf_ctrls;
408 	u8 epp_cached;
409 	u64 value;
410 	int ret;
411 
412 
413 	epp_cached = FIELD_GET(AMD_CPPC_EPP_PERF_MASK, cpudata->cppc_req_cached);
414 	if (trace_amd_pstate_epp_perf_enabled()) {
415 		union perf_cached perf = cpudata->perf;
416 
417 		trace_call__amd_pstate_epp_perf(cpudata->cpu, perf.highest_perf,
418 					  epp,
419 					  FIELD_GET(AMD_CPPC_MIN_PERF_MASK,
420 						    cpudata->cppc_req_cached),
421 					  FIELD_GET(AMD_CPPC_MAX_PERF_MASK,
422 						    cpudata->cppc_req_cached),
423 					  policy->boost_enabled,
424 					  epp != epp_cached);
425 	}
426 
427 	if (epp == epp_cached)
428 		return 0;
429 
430 	perf_ctrls.energy_perf = epp;
431 	ret = cppc_set_epp_perf(cpudata->cpu, &perf_ctrls, 1);
432 	if (ret) {
433 		pr_debug("failed to set energy perf value (%d)\n", ret);
434 		return ret;
435 	}
436 
437 	value = READ_ONCE(cpudata->cppc_req_cached);
438 	FIELD_MODIFY(AMD_CPPC_EPP_PERF_MASK, &value, epp);
439 	WRITE_ONCE(cpudata->cppc_req_cached, value);
440 
441 	return ret;
442 }
443 
444 static inline int msr_cppc_enable(struct cpufreq_policy *policy)
445 {
446 	return wrmsrq_safe_on_cpu(policy->cpu, MSR_AMD_CPPC_ENABLE, 1);
447 }
448 
449 static int shmem_cppc_enable(struct cpufreq_policy *policy)
450 {
451 	return cppc_set_enable(policy->cpu, 1);
452 }
453 
454 DEFINE_STATIC_CALL(amd_pstate_cppc_enable, msr_cppc_enable);
455 
456 static inline int amd_pstate_cppc_enable(struct cpufreq_policy *policy)
457 {
458 	return static_call(amd_pstate_cppc_enable)(policy);
459 }
460 
461 static int msr_init_perf(struct amd_cpudata *cpudata)
462 {
463 	union perf_cached perf = READ_ONCE(cpudata->perf);
464 	u64 cap1, numerator, cppc_req;
465 	u8 min_perf;
466 
467 	int ret = rdmsrq_safe_on_cpu(cpudata->cpu, MSR_AMD_CPPC_CAP1,
468 				     &cap1);
469 	if (ret)
470 		return ret;
471 
472 	ret = amd_get_boost_ratio_numerator(cpudata->cpu, &numerator);
473 	if (ret)
474 		return ret;
475 
476 	ret = rdmsrq_on_cpu(cpudata->cpu, MSR_AMD_CPPC_REQ, &cppc_req);
477 	if (ret)
478 		return ret;
479 
480 	WRITE_ONCE(cpudata->cppc_req_cached, cppc_req);
481 	min_perf = FIELD_GET(AMD_CPPC_MIN_PERF_MASK, cppc_req);
482 
483 	/*
484 	 * Clear out the min_perf part to check if the rest of the MSR is 0, if yes, this is an
485 	 * indication that the min_perf value is the one specified through the BIOS option
486 	 */
487 	cppc_req &= ~(AMD_CPPC_MIN_PERF_MASK);
488 
489 	if (!cppc_req)
490 		perf.bios_min_perf = min_perf;
491 
492 	perf.highest_perf = numerator;
493 	perf.max_limit_perf = numerator;
494 	perf.min_limit_perf = FIELD_GET(AMD_CPPC_LOWEST_PERF_MASK, cap1);
495 	perf.nominal_perf = FIELD_GET(AMD_CPPC_NOMINAL_PERF_MASK, cap1);
496 	perf.lowest_nonlinear_perf = FIELD_GET(AMD_CPPC_LOWNONLIN_PERF_MASK, cap1);
497 	perf.lowest_perf = FIELD_GET(AMD_CPPC_LOWEST_PERF_MASK, cap1);
498 	WRITE_ONCE(cpudata->perf, perf);
499 	WRITE_ONCE(cpudata->prefcore_ranking, FIELD_GET(AMD_CPPC_HIGHEST_PERF_MASK, cap1));
500 	WRITE_ONCE(cpudata->floor_perf_cnt, FIELD_GET(AMD_CPPC_FLOOR_PERF_CNT_MASK, cap1));
501 
502 	return 0;
503 }
504 
505 static int shmem_init_perf(struct amd_cpudata *cpudata)
506 {
507 	struct cppc_perf_caps cppc_perf;
508 	union perf_cached perf = READ_ONCE(cpudata->perf);
509 	u64 numerator;
510 	bool auto_sel;
511 
512 	int ret = cppc_get_perf_caps(cpudata->cpu, &cppc_perf);
513 	if (ret)
514 		return ret;
515 
516 	ret = amd_get_boost_ratio_numerator(cpudata->cpu, &numerator);
517 	if (ret)
518 		return ret;
519 
520 	perf.highest_perf = numerator;
521 	perf.max_limit_perf = numerator;
522 	perf.min_limit_perf = cppc_perf.lowest_perf;
523 	perf.nominal_perf = cppc_perf.nominal_perf;
524 	perf.lowest_nonlinear_perf = cppc_perf.lowest_nonlinear_perf;
525 	perf.lowest_perf = cppc_perf.lowest_perf;
526 	WRITE_ONCE(cpudata->perf, perf);
527 	WRITE_ONCE(cpudata->prefcore_ranking, cppc_perf.highest_perf);
528 
529 	if (cppc_state == AMD_PSTATE_ACTIVE)
530 		return 0;
531 
532 	ret = cppc_get_auto_sel(cpudata->cpu, &auto_sel);
533 	if (ret) {
534 		pr_warn("failed to get auto_sel, ret: %d\n", ret);
535 		return 0;
536 	}
537 
538 	ret = cppc_set_auto_sel(cpudata->cpu,
539 			(cppc_state == AMD_PSTATE_PASSIVE) ? 0 : 1);
540 
541 	if (ret)
542 		pr_warn("failed to set auto_sel, ret: %d\n", ret);
543 
544 	return ret;
545 }
546 
547 DEFINE_STATIC_CALL(amd_pstate_init_perf, msr_init_perf);
548 
549 static inline int amd_pstate_init_perf(struct amd_cpudata *cpudata)
550 {
551 	return static_call(amd_pstate_init_perf)(cpudata);
552 }
553 
554 static int shmem_update_perf(struct cpufreq_policy *policy, u8 min_perf,
555 			     u8 des_perf, u8 max_perf, u8 epp, bool fast_switch)
556 {
557 	struct amd_cpudata *cpudata = policy->driver_data;
558 	struct cppc_perf_ctrls perf_ctrls;
559 	u64 value, prev;
560 	int ret;
561 
562 	if (cppc_state == AMD_PSTATE_ACTIVE) {
563 		int ret = shmem_set_epp(policy, epp);
564 
565 		if (ret)
566 			return ret;
567 	}
568 
569 	value = prev = READ_ONCE(cpudata->cppc_req_cached);
570 
571 	FIELD_MODIFY(AMD_CPPC_MAX_PERF_MASK, &value, max_perf);
572 	FIELD_MODIFY(AMD_CPPC_DES_PERF_MASK, &value, des_perf);
573 	FIELD_MODIFY(AMD_CPPC_MIN_PERF_MASK, &value, min_perf);
574 	FIELD_MODIFY(AMD_CPPC_EPP_PERF_MASK, &value, epp);
575 
576 	if (trace_amd_pstate_epp_perf_enabled()) {
577 		union perf_cached perf = READ_ONCE(cpudata->perf);
578 
579 		trace_call__amd_pstate_epp_perf(cpudata->cpu,
580 					  perf.highest_perf,
581 					  epp,
582 					  min_perf,
583 					  max_perf,
584 					  policy->boost_enabled,
585 					  value != prev);
586 	}
587 
588 	if (value == prev)
589 		return 0;
590 
591 	perf_ctrls.max_perf = max_perf;
592 	perf_ctrls.min_perf = min_perf;
593 	perf_ctrls.desired_perf = des_perf;
594 
595 	ret = cppc_set_perf(cpudata->cpu, &perf_ctrls);
596 	if (ret)
597 		return ret;
598 
599 	WRITE_ONCE(cpudata->cppc_req_cached, value);
600 
601 	return 0;
602 }
603 
604 static inline bool amd_pstate_sample(struct amd_cpudata *cpudata)
605 {
606 	u64 aperf, mperf, tsc;
607 	unsigned long flags;
608 
609 	local_irq_save(flags);
610 	rdmsrq(MSR_IA32_APERF, aperf);
611 	rdmsrq(MSR_IA32_MPERF, mperf);
612 	tsc = rdtsc();
613 
614 	if (cpudata->prev.mperf == mperf || cpudata->prev.tsc == tsc) {
615 		local_irq_restore(flags);
616 		return false;
617 	}
618 
619 	local_irq_restore(flags);
620 
621 	cpudata->cur.aperf = aperf;
622 	cpudata->cur.mperf = mperf;
623 	cpudata->cur.tsc =  tsc;
624 	cpudata->cur.aperf -= cpudata->prev.aperf;
625 	cpudata->cur.mperf -= cpudata->prev.mperf;
626 	cpudata->cur.tsc -= cpudata->prev.tsc;
627 
628 	cpudata->prev.aperf = aperf;
629 	cpudata->prev.mperf = mperf;
630 	cpudata->prev.tsc = tsc;
631 
632 	cpudata->freq = div64_u64((cpudata->cur.aperf * cpu_khz), cpudata->cur.mperf);
633 
634 	return true;
635 }
636 
637 static void amd_pstate_update(struct cpufreq_policy *policy, u8 min_perf,
638 			      u8 des_perf, u8 max_perf, bool fast_switch, int gov_flags)
639 {
640 	struct amd_cpudata *cpudata = policy->driver_data;
641 	union perf_cached perf = READ_ONCE(cpudata->perf);
642 
643 	/* limit the max perf when core performance boost feature is disabled */
644 	if (!cpudata->boost_supported)
645 		max_perf = min_t(u8, perf.nominal_perf, max_perf);
646 
647 	des_perf = clamp_t(u8, des_perf, min_perf, max_perf);
648 
649 	policy->cur = perf_to_freq(perf, cpudata->nominal_freq, des_perf);
650 
651 	if ((cppc_state == AMD_PSTATE_GUIDED) && (gov_flags & CPUFREQ_GOV_DYNAMIC_SWITCHING)) {
652 		min_perf = des_perf;
653 		des_perf = 0;
654 	}
655 
656 	if (trace_amd_pstate_perf_enabled() && amd_pstate_sample(cpudata)) {
657 		trace_call__amd_pstate_perf(min_perf, des_perf, max_perf, cpudata->freq,
658 			cpudata->cur.mperf, cpudata->cur.aperf, cpudata->cur.tsc,
659 				cpudata->cpu, fast_switch);
660 	}
661 
662 	amd_pstate_update_perf(policy, min_perf, des_perf, max_perf, 0, fast_switch);
663 }
664 
665 static int amd_pstate_verify(struct cpufreq_policy_data *policy_data)
666 {
667 	/*
668 	 * Initialize lower frequency limit (i.e.policy->min) with
669 	 * lowest_nonlinear_frequency or the min frequency (if) specified in BIOS,
670 	 * Override the initial value set by cpufreq core and amd-pstate qos_requests.
671 	 */
672 	if (policy_data->min == FREQ_QOS_MIN_DEFAULT_VALUE) {
673 		struct cpufreq_policy *policy __free(put_cpufreq_policy) =
674 					      cpufreq_cpu_get(policy_data->cpu);
675 		struct amd_cpudata *cpudata;
676 		union perf_cached perf;
677 
678 		if (!policy)
679 			return -EINVAL;
680 
681 		cpudata = policy->driver_data;
682 		perf = READ_ONCE(cpudata->perf);
683 
684 		if (perf.bios_min_perf)
685 			policy_data->min = perf_to_freq(perf, cpudata->nominal_freq,
686 							perf.bios_min_perf);
687 		else
688 			policy_data->min = cpudata->lowest_nonlinear_freq;
689 	}
690 
691 	cpufreq_verify_within_cpu_limits(policy_data);
692 
693 	return 0;
694 }
695 
696 static void amd_pstate_update_min_max_limit(struct cpufreq_policy *policy)
697 {
698 	struct amd_cpudata *cpudata = policy->driver_data;
699 	union perf_cached perf = READ_ONCE(cpudata->perf);
700 
701 	perf.max_limit_perf = freq_to_perf(perf, cpudata->nominal_freq, policy->max);
702 	WRITE_ONCE(cpudata->max_limit_freq, policy->max);
703 
704 	if (cpudata->policy == CPUFREQ_POLICY_PERFORMANCE) {
705 		/*
706 		 * For performance policy, set MinPerf to nominal_perf rather than
707 		 * highest_perf or lowest_nonlinear_perf.
708 		 *
709 		 * Per commit 0c411b39e4f4c, using highest_perf was observed
710 		 * to cause frequency throttling on power-limited platforms, leading to
711 		 * performance regressions. Using lowest_nonlinear_perf would limit
712 		 * performance too much for HPC workloads requiring high frequency
713 		 * operation and minimal wakeup latency from idle states.
714 		 *
715 		 * nominal_perf therefore provides a balance by avoiding throttling
716 		 * while still maintaining enough performance for HPC workloads.
717 		 */
718 		perf.min_limit_perf = min(perf.nominal_perf, perf.max_limit_perf);
719 		WRITE_ONCE(cpudata->min_limit_freq, min(cpudata->nominal_freq, cpudata->max_limit_freq));
720 	} else {
721 		perf.min_limit_perf = freq_to_perf(perf, cpudata->nominal_freq, policy->min);
722 		WRITE_ONCE(cpudata->min_limit_freq, policy->min);
723 	}
724 
725 	WRITE_ONCE(cpudata->perf, perf);
726 }
727 
728 static int amd_pstate_update_freq(struct cpufreq_policy *policy,
729 				  unsigned int target_freq, bool fast_switch)
730 {
731 	struct cpufreq_freqs freqs;
732 	struct amd_cpudata *cpudata;
733 	union perf_cached perf;
734 	u8 des_perf;
735 
736 	cpudata = policy->driver_data;
737 
738 	if (policy->min != cpudata->min_limit_freq || policy->max != cpudata->max_limit_freq)
739 		amd_pstate_update_min_max_limit(policy);
740 
741 	perf = READ_ONCE(cpudata->perf);
742 
743 	freqs.old = policy->cur;
744 	freqs.new = target_freq;
745 
746 	des_perf = freq_to_perf(perf, cpudata->nominal_freq, target_freq);
747 
748 	WARN_ON(fast_switch && !policy->fast_switch_enabled);
749 	/*
750 	 * If fast_switch is desired, then there aren't any registered
751 	 * transition notifiers. See comment for
752 	 * cpufreq_enable_fast_switch().
753 	 */
754 	if (!fast_switch)
755 		cpufreq_freq_transition_begin(policy, &freqs);
756 
757 	amd_pstate_update(policy, perf.min_limit_perf, des_perf,
758 			  perf.max_limit_perf, fast_switch,
759 			  policy->governor->flags);
760 
761 	if (!fast_switch)
762 		cpufreq_freq_transition_end(policy, &freqs, false);
763 
764 	return 0;
765 }
766 
767 static int amd_pstate_target(struct cpufreq_policy *policy,
768 			     unsigned int target_freq,
769 			     unsigned int relation)
770 {
771 	return amd_pstate_update_freq(policy, target_freq, false);
772 }
773 
774 static unsigned int amd_pstate_fast_switch(struct cpufreq_policy *policy,
775 				  unsigned int target_freq)
776 {
777 	if (!amd_pstate_update_freq(policy, target_freq, true))
778 		return target_freq;
779 	return policy->cur;
780 }
781 
782 static void amd_pstate_adjust_perf(struct cpufreq_policy *policy,
783 				   unsigned long _min_perf,
784 				   unsigned long target_perf,
785 				   unsigned long capacity)
786 {
787 	u8 max_perf, min_perf, des_perf, cap_perf;
788 	struct amd_cpudata *cpudata;
789 	union perf_cached perf;
790 
791 	if (!policy)
792 		return;
793 
794 	cpudata = policy->driver_data;
795 
796 	if (policy->min != cpudata->min_limit_freq || policy->max != cpudata->max_limit_freq)
797 		amd_pstate_update_min_max_limit(policy);
798 
799 	perf = READ_ONCE(cpudata->perf);
800 	cap_perf = perf.highest_perf;
801 
802 	des_perf = cap_perf;
803 	if (target_perf < capacity)
804 		des_perf = DIV_ROUND_UP(cap_perf * target_perf, capacity);
805 
806 	if (_min_perf < capacity)
807 		min_perf = DIV_ROUND_UP(cap_perf * _min_perf, capacity);
808 	else
809 		min_perf = cap_perf;
810 
811 	if (min_perf < perf.min_limit_perf)
812 		min_perf = perf.min_limit_perf;
813 
814 	max_perf = perf.max_limit_perf;
815 	if (max_perf < min_perf)
816 		max_perf = min_perf;
817 
818 	amd_pstate_update(policy, min_perf, des_perf, max_perf, true,
819 			policy->governor->flags);
820 }
821 
822 static int amd_pstate_cpu_boost_update(struct cpufreq_policy *policy, bool on)
823 {
824 	struct amd_cpudata *cpudata = policy->driver_data;
825 	u32 nominal_freq;
826 	int ret = 0;
827 
828 	nominal_freq = READ_ONCE(cpudata->nominal_freq);
829 
830 	if (on)
831 		policy->cpuinfo.max_freq = cpudata->max_freq;
832 	else if (policy->cpuinfo.max_freq > nominal_freq)
833 		policy->cpuinfo.max_freq = nominal_freq;
834 
835 	if (cppc_state == AMD_PSTATE_PASSIVE) {
836 		ret = freq_qos_update_request(&cpudata->req[1], policy->cpuinfo.max_freq);
837 		if (ret < 0)
838 			pr_debug("Failed to update freq constraint: CPU%d\n", cpudata->cpu);
839 	}
840 
841 	return ret < 0 ? ret : 0;
842 }
843 
844 static int amd_pstate_set_boost(struct cpufreq_policy *policy, int state)
845 {
846 	struct amd_cpudata *cpudata = policy->driver_data;
847 	int ret;
848 
849 	if (!cpudata->boost_supported) {
850 		pr_err("Boost mode is not supported by this processor or SBIOS\n");
851 		return -EOPNOTSUPP;
852 	}
853 
854 	ret = amd_pstate_cpu_boost_update(policy, state);
855 	refresh_frequency_limits(policy);
856 
857 	return ret;
858 }
859 
860 static int amd_pstate_init_boost_support(struct amd_cpudata *cpudata)
861 {
862 	u64 boost_val;
863 	int ret = -1;
864 
865 	/*
866 	 * If platform has no CPB support or disable it, initialize current driver
867 	 * boost_enabled state to be false, it is not an error for cpufreq core to handle.
868 	 */
869 	if (!cpu_feature_enabled(X86_FEATURE_CPB)) {
870 		pr_debug_once("Boost CPB capabilities not present in the processor\n");
871 		ret = 0;
872 		goto exit_err;
873 	}
874 
875 	ret = rdmsrq_on_cpu(cpudata->cpu, MSR_K7_HWCR, &boost_val);
876 	if (ret) {
877 		pr_err_once("failed to read initial CPU boost state!\n");
878 		ret = -EIO;
879 		goto exit_err;
880 	}
881 
882 	if (!(boost_val & MSR_K7_HWCR_CPB_DIS))
883 		cpudata->boost_supported = true;
884 
885 	return 0;
886 
887 exit_err:
888 	cpudata->boost_supported = false;
889 	return ret;
890 }
891 
892 static void amd_perf_ctl_reset(unsigned int cpu)
893 {
894 	wrmsrq_on_cpu(cpu, MSR_AMD_PERF_CTL, 0);
895 }
896 
897 #define CPPC_MAX_PERF	U8_MAX
898 
899 static void amd_pstate_init_prefcore(struct amd_cpudata *cpudata)
900 {
901 	/* user disabled or not detected */
902 	if (!amd_pstate_prefcore)
903 		return;
904 
905 	/* should use amd-hfi instead */
906 	if (cpu_feature_enabled(X86_FEATURE_AMD_WORKLOAD_CLASS) &&
907 	    IS_ENABLED(CONFIG_AMD_HFI)) {
908 		amd_pstate_prefcore = false;
909 		return;
910 	}
911 
912 	cpudata->hw_prefcore = true;
913 
914 	/* Priorities must be initialized before ITMT support can be toggled on. */
915 	sched_set_itmt_core_prio((int)READ_ONCE(cpudata->prefcore_ranking), cpudata->cpu);
916 }
917 
918 static void amd_pstate_update_limits(struct cpufreq_policy *policy)
919 {
920 	struct amd_cpudata *cpudata;
921 	u32 prev_high = 0, cur_high = 0;
922 	bool highest_perf_changed = false;
923 	unsigned int cpu = policy->cpu;
924 
925 	if (!amd_pstate_prefcore)
926 		return;
927 
928 	if (amd_get_highest_perf(cpu, &cur_high))
929 		return;
930 
931 	cpudata = policy->driver_data;
932 
933 	prev_high = READ_ONCE(cpudata->prefcore_ranking);
934 	highest_perf_changed = (prev_high != cur_high);
935 	if (highest_perf_changed) {
936 		WRITE_ONCE(cpudata->prefcore_ranking, cur_high);
937 
938 		if (cur_high < CPPC_MAX_PERF) {
939 			sched_set_itmt_core_prio((int)cur_high, cpu);
940 			sched_update_asym_prefer_cpu(cpu, prev_high, cur_high);
941 		}
942 	}
943 }
944 
945 /*
946  * Get pstate transition delay time from ACPI tables that firmware set
947  * instead of using hardcode value directly.
948  */
949 static u32 amd_pstate_get_transition_delay_us(unsigned int cpu)
950 {
951 	int transition_delay_ns;
952 
953 	transition_delay_ns = cppc_get_transition_latency(cpu);
954 	if (transition_delay_ns < 0) {
955 		if (cpu_feature_enabled(X86_FEATURE_AMD_FAST_CPPC))
956 			return AMD_PSTATE_FAST_CPPC_TRANSITION_DELAY;
957 		else
958 			return AMD_PSTATE_TRANSITION_DELAY;
959 	}
960 
961 	return transition_delay_ns / NSEC_PER_USEC;
962 }
963 
964 /*
965  * Get pstate transition latency value from ACPI tables that firmware
966  * set instead of using hardcode value directly.
967  */
968 static u32 amd_pstate_get_transition_latency(unsigned int cpu)
969 {
970 	int transition_latency;
971 
972 	transition_latency = cppc_get_transition_latency(cpu);
973 	if (transition_latency < 0)
974 		return AMD_PSTATE_TRANSITION_LATENCY;
975 
976 	return transition_latency;
977 }
978 
979 /*
980  * amd_pstate_init_freq: Initialize the nominal_freq and lowest_nonlinear_freq
981  *			 for the @cpudata object.
982  *
983  * Requires: all perf members of @cpudata to be initialized.
984  *
985  * Returns 0 on success, non-zero value on failure.
986  */
987 static int amd_pstate_init_freq(struct amd_cpudata *cpudata)
988 {
989 	u32 min_freq, max_freq, nominal_freq, lowest_nonlinear_freq;
990 	struct cppc_perf_caps cppc_perf;
991 	union perf_cached perf;
992 	int ret;
993 
994 	ret = cppc_get_perf_caps(cpudata->cpu, &cppc_perf);
995 	if (ret)
996 		return ret;
997 	perf = READ_ONCE(cpudata->perf);
998 
999 	if (quirks && quirks->nominal_freq)
1000 		nominal_freq = quirks->nominal_freq;
1001 	else
1002 		nominal_freq = cppc_perf.nominal_freq;
1003 	nominal_freq *= 1000;
1004 
1005 	if (quirks && quirks->lowest_freq) {
1006 		min_freq = quirks->lowest_freq;
1007 		perf.lowest_perf = freq_to_perf(perf, nominal_freq, min_freq);
1008 		WRITE_ONCE(cpudata->perf, perf);
1009 	} else
1010 		min_freq = cppc_perf.lowest_freq;
1011 
1012 	min_freq *= 1000;
1013 
1014 	WRITE_ONCE(cpudata->nominal_freq, nominal_freq);
1015 
1016 	/* max_freq is calculated according to (nominal_freq * highest_perf)/nominal_perf */
1017 	max_freq = perf_to_freq(perf, nominal_freq, perf.highest_perf);
1018 	WRITE_ONCE(cpudata->max_freq, max_freq);
1019 
1020 	lowest_nonlinear_freq = perf_to_freq(perf, nominal_freq, perf.lowest_nonlinear_perf);
1021 	WRITE_ONCE(cpudata->lowest_nonlinear_freq, lowest_nonlinear_freq);
1022 
1023 	/**
1024 	 * Below values need to be initialized correctly, otherwise driver will fail to load
1025 	 * lowest_nonlinear_freq is a value between [min_freq, nominal_freq]
1026 	 * Check _CPC in ACPI table objects if any values are incorrect
1027 	 */
1028 	if (min_freq <= 0 || max_freq <= 0 || nominal_freq <= 0 || min_freq > max_freq) {
1029 		pr_err("min_freq(%d) or max_freq(%d) or nominal_freq(%d) value is incorrect\n",
1030 			min_freq, max_freq, nominal_freq);
1031 		return -EINVAL;
1032 	}
1033 
1034 	if (lowest_nonlinear_freq <= min_freq || lowest_nonlinear_freq > nominal_freq) {
1035 		pr_err("lowest_nonlinear_freq(%d) value is out of range [min_freq(%d), nominal_freq(%d)]\n",
1036 			lowest_nonlinear_freq, min_freq, nominal_freq);
1037 		return -EINVAL;
1038 	}
1039 
1040 	return 0;
1041 }
1042 
1043 static int amd_pstate_cpu_init(struct cpufreq_policy *policy)
1044 {
1045 	struct amd_cpudata *cpudata;
1046 	union perf_cached perf;
1047 	struct device *dev;
1048 	int ret;
1049 
1050 	/*
1051 	 * Resetting PERF_CTL_MSR will put the CPU in P0 frequency,
1052 	 * which is ideal for initialization process.
1053 	 */
1054 	amd_perf_ctl_reset(policy->cpu);
1055 	dev = get_cpu_device(policy->cpu);
1056 	if (!dev)
1057 		return -ENODEV;
1058 
1059 	cpudata = kzalloc_obj(*cpudata);
1060 	if (!cpudata)
1061 		return -ENOMEM;
1062 
1063 	cpudata->cpu = policy->cpu;
1064 
1065 	ret = amd_pstate_init_perf(cpudata);
1066 	if (ret)
1067 		goto free_cpudata1;
1068 
1069 	amd_pstate_init_prefcore(cpudata);
1070 
1071 	ret = amd_pstate_init_freq(cpudata);
1072 	if (ret)
1073 		goto free_cpudata1;
1074 
1075 	ret = amd_pstate_init_boost_support(cpudata);
1076 	if (ret)
1077 		goto free_cpudata1;
1078 
1079 	policy->cpuinfo.transition_latency = amd_pstate_get_transition_latency(policy->cpu);
1080 	policy->transition_delay_us = amd_pstate_get_transition_delay_us(policy->cpu);
1081 
1082 	perf = READ_ONCE(cpudata->perf);
1083 
1084 	policy->cpuinfo.min_freq = perf_to_freq(perf, cpudata->nominal_freq,
1085 						perf.lowest_perf);
1086 	policy->cpuinfo.max_freq = cpudata->max_freq;
1087 
1088 	policy->driver_data = cpudata;
1089 	ret = amd_pstate_cppc_enable(policy);
1090 	if (ret)
1091 		goto free_cpudata1;
1092 
1093 	policy->boost_supported = READ_ONCE(cpudata->boost_supported);
1094 
1095 	/* It will be updated by governor */
1096 	policy->cur = policy->cpuinfo.min_freq;
1097 
1098 	if (cpu_feature_enabled(X86_FEATURE_CPPC))
1099 		policy->fast_switch_possible = true;
1100 
1101 	ret = amd_pstate_init_floor_perf(policy);
1102 	if (ret) {
1103 		dev_err(dev, "Failed to initialize Floor Perf (%d)\n", ret);
1104 		goto free_cpudata1;
1105 	}
1106 
1107 	ret = freq_qos_add_request(&policy->constraints, &cpudata->req[0],
1108 				   FREQ_QOS_MIN, FREQ_QOS_MIN_DEFAULT_VALUE);
1109 	if (ret < 0) {
1110 		dev_err(dev, "Failed to add min-freq constraint (%d)\n", ret);
1111 		goto free_cpudata1;
1112 	}
1113 
1114 	ret = freq_qos_add_request(&policy->constraints, &cpudata->req[1],
1115 				   FREQ_QOS_MAX, policy->cpuinfo.max_freq);
1116 	if (ret < 0) {
1117 		dev_err(dev, "Failed to add max-freq constraint (%d)\n", ret);
1118 		goto free_cpudata2;
1119 	}
1120 
1121 
1122 	if (!current_pstate_driver->adjust_perf)
1123 		current_pstate_driver->adjust_perf = amd_pstate_adjust_perf;
1124 
1125 	return 0;
1126 
1127 free_cpudata2:
1128 	freq_qos_remove_request(&cpudata->req[0]);
1129 free_cpudata1:
1130 	pr_warn("Failed to initialize CPU %d: %d\n", policy->cpu, ret);
1131 	kfree(cpudata);
1132 	policy->driver_data = NULL;
1133 	return ret;
1134 }
1135 
1136 static void amd_pstate_cpu_exit(struct cpufreq_policy *policy)
1137 {
1138 	struct amd_cpudata *cpudata = policy->driver_data;
1139 	union perf_cached perf = READ_ONCE(cpudata->perf);
1140 
1141 	/* Reset CPPC_REQ MSR to the BIOS value */
1142 	amd_pstate_update_perf(policy, perf.bios_min_perf, 0U, 0U, 0U, false);
1143 	amd_pstate_set_floor_perf(policy, cpudata->bios_floor_perf);
1144 
1145 	freq_qos_remove_request(&cpudata->req[1]);
1146 	freq_qos_remove_request(&cpudata->req[0]);
1147 	policy->fast_switch_possible = false;
1148 	kfree(cpudata);
1149 }
1150 
1151 static int amd_pstate_get_balanced_epp(struct cpufreq_policy *policy)
1152 {
1153 	struct amd_cpudata *cpudata = policy->driver_data;
1154 
1155 	if (power_supply_is_system_supplied())
1156 		return cpudata->epp_default_ac;
1157 	else
1158 		return cpudata->epp_default_dc;
1159 }
1160 
1161 static int amd_pstate_power_supply_notifier(struct notifier_block *nb,
1162 					    unsigned long event, void *data)
1163 {
1164 	struct amd_cpudata *cpudata = container_of(nb, struct amd_cpudata, power_nb);
1165 	struct cpufreq_policy *policy __free(put_cpufreq_policy) = cpufreq_cpu_get(cpudata->cpu);
1166 	u8 epp;
1167 	int ret;
1168 
1169 	if (event != PSY_EVENT_PROP_CHANGED)
1170 		return NOTIFY_OK;
1171 
1172 	/* dynamic actions are only applied while platform profile is in balanced */
1173 	if (cpudata->current_profile != PLATFORM_PROFILE_BALANCED)
1174 		return 0;
1175 
1176 	epp = amd_pstate_get_balanced_epp(policy);
1177 
1178 	ret = amd_pstate_set_epp(policy, epp);
1179 	if (ret)
1180 		pr_warn("Failed to set CPU %d EPP %u: %d\n", cpudata->cpu, epp, ret);
1181 
1182 	return NOTIFY_OK;
1183 }
1184 
1185 static int amd_pstate_profile_probe(void *drvdata, unsigned long *choices)
1186 {
1187 	set_bit(PLATFORM_PROFILE_LOW_POWER, choices);
1188 	set_bit(PLATFORM_PROFILE_BALANCED, choices);
1189 	set_bit(PLATFORM_PROFILE_PERFORMANCE, choices);
1190 
1191 	return 0;
1192 }
1193 
1194 static int amd_pstate_profile_get(struct device *dev,
1195 				  enum platform_profile_option *profile)
1196 {
1197 	struct amd_cpudata *cpudata = dev_get_drvdata(dev);
1198 
1199 	*profile = cpudata->current_profile;
1200 
1201 	return 0;
1202 }
1203 
1204 static int amd_pstate_profile_set(struct device *dev,
1205 				  enum platform_profile_option profile)
1206 {
1207 	struct amd_cpudata *cpudata = dev_get_drvdata(dev);
1208 	struct cpufreq_policy *policy __free(put_cpufreq_policy) = cpufreq_cpu_get(cpudata->cpu);
1209 	int ret;
1210 
1211 	switch (profile) {
1212 	case PLATFORM_PROFILE_LOW_POWER:
1213 		ret = amd_pstate_set_epp(policy, AMD_CPPC_EPP_POWERSAVE);
1214 		if (ret)
1215 			return ret;
1216 		break;
1217 	case PLATFORM_PROFILE_BALANCED:
1218 		ret = amd_pstate_set_epp(policy,
1219 					 amd_pstate_get_balanced_epp(policy));
1220 		if (ret)
1221 			return ret;
1222 		break;
1223 	case PLATFORM_PROFILE_PERFORMANCE:
1224 		ret = amd_pstate_set_epp(policy, AMD_CPPC_EPP_PERFORMANCE);
1225 		if (ret)
1226 			return ret;
1227 		break;
1228 	default:
1229 		pr_err("Unknown Platform Profile %d\n", profile);
1230 		return -EOPNOTSUPP;
1231 	}
1232 
1233 	cpudata->current_profile = profile;
1234 
1235 	return 0;
1236 }
1237 
1238 static const struct platform_profile_ops amd_pstate_profile_ops = {
1239 	.probe = amd_pstate_profile_probe,
1240 	.profile_set = amd_pstate_profile_set,
1241 	.profile_get = amd_pstate_profile_get,
1242 };
1243 
1244 void amd_pstate_clear_dynamic_epp(struct cpufreq_policy *policy)
1245 {
1246 	struct amd_cpudata *cpudata = policy->driver_data;
1247 
1248 	if (cpudata->power_nb.notifier_call)
1249 		power_supply_unreg_notifier(&cpudata->power_nb);
1250 	if (cpudata->ppdev) {
1251 		platform_profile_remove(cpudata->ppdev);
1252 		cpudata->ppdev = NULL;
1253 	}
1254 	kfree(cpudata->profile_name);
1255 	cpudata->dynamic_epp = false;
1256 }
1257 EXPORT_SYMBOL_GPL(amd_pstate_clear_dynamic_epp);
1258 
1259 static int amd_pstate_set_dynamic_epp(struct cpufreq_policy *policy)
1260 {
1261 	struct amd_cpudata *cpudata = policy->driver_data;
1262 	int ret;
1263 	u8 epp;
1264 
1265 	switch (cpudata->current_profile) {
1266 	case PLATFORM_PROFILE_PERFORMANCE:
1267 		epp = AMD_CPPC_EPP_PERFORMANCE;
1268 		break;
1269 	case PLATFORM_PROFILE_LOW_POWER:
1270 		epp = AMD_CPPC_EPP_POWERSAVE;
1271 		break;
1272 	case PLATFORM_PROFILE_BALANCED:
1273 		epp = amd_pstate_get_balanced_epp(policy);
1274 		break;
1275 	default:
1276 		pr_err("Unknown Platform Profile %d\n", cpudata->current_profile);
1277 		return -EOPNOTSUPP;
1278 	}
1279 	ret = amd_pstate_set_epp(policy, epp);
1280 	if (ret)
1281 		return ret;
1282 
1283 	cpudata->profile_name = kasprintf(GFP_KERNEL, "amd-pstate-epp-cpu%d", cpudata->cpu);
1284 	if (!cpudata->profile_name)
1285 		return -ENOMEM;
1286 
1287 	cpudata->ppdev = platform_profile_register(get_cpu_device(policy->cpu),
1288 						   cpudata->profile_name,
1289 						   policy->driver_data,
1290 						   &amd_pstate_profile_ops);
1291 	if (IS_ERR(cpudata->ppdev)) {
1292 		ret = PTR_ERR(cpudata->ppdev);
1293 		goto cleanup;
1294 	}
1295 
1296 	/* only enable notifier if things will actually change */
1297 	if (cpudata->epp_default_ac != cpudata->epp_default_dc) {
1298 		cpudata->power_nb.notifier_call = amd_pstate_power_supply_notifier;
1299 		ret = power_supply_reg_notifier(&cpudata->power_nb);
1300 		if (ret)
1301 			goto cleanup;
1302 	}
1303 
1304 	cpudata->dynamic_epp = true;
1305 
1306 	return 0;
1307 
1308 cleanup:
1309 	amd_pstate_clear_dynamic_epp(policy);
1310 
1311 	return ret;
1312 }
1313 
1314 /* Sysfs attributes */
1315 
1316 /*
1317  * This frequency is to indicate the maximum hardware frequency.
1318  * If boost is not active but supported, the frequency will be larger than the
1319  * one in cpuinfo.
1320  */
1321 static ssize_t show_amd_pstate_max_freq(struct cpufreq_policy *policy,
1322 					char *buf)
1323 {
1324 	struct amd_cpudata *cpudata = policy->driver_data;
1325 
1326 	return sysfs_emit(buf, "%u\n", cpudata->max_freq);
1327 }
1328 
1329 static ssize_t show_amd_pstate_lowest_nonlinear_freq(struct cpufreq_policy *policy,
1330 						     char *buf)
1331 {
1332 	struct amd_cpudata *cpudata;
1333 	union perf_cached perf;
1334 
1335 	cpudata = policy->driver_data;
1336 	perf = READ_ONCE(cpudata->perf);
1337 
1338 	return sysfs_emit(buf, "%u\n",
1339 			  perf_to_freq(perf, cpudata->nominal_freq, perf.lowest_nonlinear_perf));
1340 }
1341 
1342 /*
1343  * In some of ASICs, the highest_perf is not the one in the _CPC table, so we
1344  * need to expose it to sysfs.
1345  */
1346 static ssize_t show_amd_pstate_highest_perf(struct cpufreq_policy *policy,
1347 					    char *buf)
1348 {
1349 	struct amd_cpudata *cpudata;
1350 
1351 	cpudata = policy->driver_data;
1352 
1353 	return sysfs_emit(buf, "%u\n", cpudata->perf.highest_perf);
1354 }
1355 
1356 static ssize_t show_amd_pstate_prefcore_ranking(struct cpufreq_policy *policy,
1357 						char *buf)
1358 {
1359 	u8 perf;
1360 	struct amd_cpudata *cpudata = policy->driver_data;
1361 
1362 	perf = READ_ONCE(cpudata->prefcore_ranking);
1363 
1364 	return sysfs_emit(buf, "%u\n", perf);
1365 }
1366 
1367 static ssize_t show_amd_pstate_hw_prefcore(struct cpufreq_policy *policy,
1368 					   char *buf)
1369 {
1370 	bool hw_prefcore;
1371 	struct amd_cpudata *cpudata = policy->driver_data;
1372 
1373 	hw_prefcore = READ_ONCE(cpudata->hw_prefcore);
1374 
1375 	return sysfs_emit(buf, "%s\n", str_enabled_disabled(hw_prefcore));
1376 }
1377 
1378 static ssize_t show_energy_performance_available_preferences(
1379 				struct cpufreq_policy *policy, char *buf)
1380 {
1381 	int offset = 0, i;
1382 	struct amd_cpudata *cpudata = policy->driver_data;
1383 
1384 	if (cpudata->policy == CPUFREQ_POLICY_PERFORMANCE)
1385 		return sysfs_emit_at(buf, offset, "%s\n",
1386 				energy_perf_strings[EPP_INDEX_PERFORMANCE]);
1387 
1388 	for (i = 0; i < ARRAY_SIZE(energy_perf_strings); i++)
1389 		offset += sysfs_emit_at(buf, offset, "%s ", energy_perf_strings[i]);
1390 
1391 	offset += sysfs_emit_at(buf, offset, "\n");
1392 
1393 	return offset;
1394 }
1395 
1396 ssize_t store_energy_performance_preference(struct cpufreq_policy *policy,
1397 				    const char *buf, size_t count)
1398 {
1399 	struct amd_cpudata *cpudata = policy->driver_data;
1400 	ssize_t ret;
1401 	bool raw_epp = false;
1402 	u8 epp;
1403 
1404 	if (cpudata->dynamic_epp) {
1405 		pr_debug("EPP cannot be set when dynamic EPP is enabled\n");
1406 		return -EBUSY;
1407 	}
1408 
1409 	/*
1410 	 * if the value matches a number, use that, otherwise see if
1411 	 * matches an index in the energy_perf_strings array
1412 	 */
1413 	ret = kstrtou8(buf, 0, &epp);
1414 	raw_epp = !ret;
1415 	if (ret) {
1416 		ret = sysfs_match_string(energy_perf_strings, buf);
1417 		if (ret < 0 || ret == EPP_INDEX_CUSTOM)
1418 			return -EINVAL;
1419 		if (ret)
1420 			epp = epp_values[ret];
1421 		else
1422 			epp = cpudata->epp_default_dc;
1423 	}
1424 
1425 	if (epp > 0 && cpudata->policy == CPUFREQ_POLICY_PERFORMANCE) {
1426 		pr_debug("EPP cannot be set under performance policy\n");
1427 		return -EBUSY;
1428 	}
1429 
1430 	ret = amd_pstate_set_epp(policy, epp);
1431 	if (ret)
1432 		return ret;
1433 
1434 	cpudata->raw_epp = raw_epp;
1435 
1436 	return count;
1437 }
1438 EXPORT_SYMBOL_GPL(store_energy_performance_preference);
1439 
1440 ssize_t show_energy_performance_preference(struct cpufreq_policy *policy, char *buf)
1441 {
1442 	struct amd_cpudata *cpudata = policy->driver_data;
1443 	u8 preference, epp;
1444 
1445 	epp = FIELD_GET(AMD_CPPC_EPP_PERF_MASK, cpudata->cppc_req_cached);
1446 
1447 	if (cpudata->raw_epp)
1448 		return sysfs_emit(buf, "%u\n", epp);
1449 
1450 	switch (epp) {
1451 	case AMD_CPPC_EPP_PERFORMANCE:
1452 		preference = EPP_INDEX_PERFORMANCE;
1453 		break;
1454 	case AMD_CPPC_EPP_BALANCE_PERFORMANCE:
1455 		preference = EPP_INDEX_BALANCE_PERFORMANCE;
1456 		break;
1457 	case AMD_CPPC_EPP_BALANCE_POWERSAVE:
1458 		preference = EPP_INDEX_BALANCE_POWERSAVE;
1459 		break;
1460 	case AMD_CPPC_EPP_POWERSAVE:
1461 		preference = EPP_INDEX_POWERSAVE;
1462 		break;
1463 	default:
1464 		return -EINVAL;
1465 	}
1466 
1467 	return sysfs_emit(buf, "%s\n", energy_perf_strings[preference]);
1468 }
1469 EXPORT_SYMBOL_GPL(show_energy_performance_preference);
1470 
1471 static ssize_t store_amd_pstate_floor_freq(struct cpufreq_policy *policy,
1472 					   const char *buf, size_t count)
1473 {
1474 	struct amd_cpudata *cpudata = policy->driver_data;
1475 	union perf_cached perf = READ_ONCE(cpudata->perf);
1476 	unsigned int freq;
1477 	u8 floor_perf;
1478 	int ret;
1479 
1480 	ret = kstrtouint(buf, 0, &freq);
1481 	if (ret)
1482 		return ret;
1483 
1484 	if (freq < policy->cpuinfo.min_freq || freq > policy->max)
1485 		return -EINVAL;
1486 
1487 	floor_perf = freq_to_perf(perf, cpudata->nominal_freq, freq);
1488 	ret = amd_pstate_set_floor_perf(policy, floor_perf);
1489 
1490 	if (!ret)
1491 		cpudata->floor_freq = freq;
1492 
1493 	return ret ?: count;
1494 }
1495 
1496 static ssize_t show_amd_pstate_floor_freq(struct cpufreq_policy *policy, char *buf)
1497 {
1498 	struct amd_cpudata *cpudata = policy->driver_data;
1499 
1500 	return sysfs_emit(buf, "%u\n", cpudata->floor_freq);
1501 }
1502 
1503 static ssize_t show_amd_pstate_floor_count(struct cpufreq_policy *policy, char *buf)
1504 {
1505 	struct amd_cpudata *cpudata = policy->driver_data;
1506 	u8 count = cpudata->floor_perf_cnt;
1507 
1508 	return sysfs_emit(buf, "%u\n", count);
1509 }
1510 
1511 cpufreq_freq_attr_ro(amd_pstate_max_freq);
1512 cpufreq_freq_attr_ro(amd_pstate_lowest_nonlinear_freq);
1513 
1514 cpufreq_freq_attr_ro(amd_pstate_highest_perf);
1515 cpufreq_freq_attr_ro(amd_pstate_prefcore_ranking);
1516 cpufreq_freq_attr_ro(amd_pstate_hw_prefcore);
1517 cpufreq_freq_attr_rw(energy_performance_preference);
1518 cpufreq_freq_attr_ro(energy_performance_available_preferences);
1519 cpufreq_freq_attr_rw(amd_pstate_floor_freq);
1520 cpufreq_freq_attr_ro(amd_pstate_floor_count);
1521 
1522 struct freq_attr_visibility {
1523 	struct freq_attr *attr;
1524 	bool (*visibility_fn)(void);
1525 };
1526 
1527 /* For attributes which are always visible */
1528 static bool always_visible(void)
1529 {
1530 	return true;
1531 }
1532 
1533 /* Determines whether prefcore related attributes should be visible */
1534 static bool prefcore_visibility(void)
1535 {
1536 	return amd_pstate_prefcore;
1537 }
1538 
1539 /* Determines whether energy performance preference should be visible */
1540 static bool epp_visibility(void)
1541 {
1542 	return cppc_state == AMD_PSTATE_ACTIVE;
1543 }
1544 
1545 /* Determines whether amd_pstate_floor_freq related attributes should be visible */
1546 static bool floor_freq_visibility(void)
1547 {
1548 	return cpu_feature_enabled(X86_FEATURE_CPPC_PERF_PRIO);
1549 }
1550 
1551 static struct freq_attr_visibility amd_pstate_attr_visibility[] = {
1552 	{&amd_pstate_max_freq, always_visible},
1553 	{&amd_pstate_lowest_nonlinear_freq, always_visible},
1554 	{&amd_pstate_highest_perf, always_visible},
1555 	{&amd_pstate_prefcore_ranking, prefcore_visibility},
1556 	{&amd_pstate_hw_prefcore, prefcore_visibility},
1557 	{&energy_performance_preference, epp_visibility},
1558 	{&energy_performance_available_preferences, epp_visibility},
1559 	{&amd_pstate_floor_freq, floor_freq_visibility},
1560 	{&amd_pstate_floor_count, floor_freq_visibility},
1561 };
1562 
1563 struct freq_attr **amd_pstate_get_current_attrs(void)
1564 {
1565 	if (!current_pstate_driver)
1566 		return NULL;
1567 	return current_pstate_driver->attr;
1568 }
1569 EXPORT_SYMBOL_GPL(amd_pstate_get_current_attrs);
1570 
1571 static struct freq_attr **get_freq_attrs(void)
1572 {
1573 	bool attr_visible[ARRAY_SIZE(amd_pstate_attr_visibility)];
1574 	struct freq_attr **attrs;
1575 	int i, j, count;
1576 
1577 	for (i = 0, count = 0; i < ARRAY_SIZE(amd_pstate_attr_visibility); i++) {
1578 		struct freq_attr_visibility *v = &amd_pstate_attr_visibility[i];
1579 
1580 		attr_visible[i] = v->visibility_fn();
1581 		if (attr_visible[i])
1582 			count++;
1583 	}
1584 
1585 	/* amd_pstate_{max_freq, lowest_nonlinear_freq, highest_perf} should always be visible */
1586 	BUG_ON(!count);
1587 
1588 	attrs = kcalloc(count + 1, sizeof(struct freq_attr *), GFP_KERNEL);
1589 	if (!attrs)
1590 		return ERR_PTR(-ENOMEM);
1591 
1592 	for (i = 0, j = 0; i < ARRAY_SIZE(amd_pstate_attr_visibility); i++) {
1593 		if (!attr_visible[i])
1594 			continue;
1595 
1596 		attrs[j++] = amd_pstate_attr_visibility[i].attr;
1597 	}
1598 
1599 	return attrs;
1600 }
1601 
1602 static void amd_pstate_driver_cleanup(void)
1603 {
1604 	if (amd_pstate_prefcore)
1605 		sched_clear_itmt_support();
1606 
1607 	cppc_state = AMD_PSTATE_DISABLE;
1608 	kfree(current_pstate_driver->attr);
1609 	current_pstate_driver->attr = NULL;
1610 	current_pstate_driver = NULL;
1611 }
1612 
1613 static int amd_pstate_set_driver(int mode_idx)
1614 {
1615 	if (mode_idx >= AMD_PSTATE_DISABLE && mode_idx < AMD_PSTATE_MAX) {
1616 		cppc_state = mode_idx;
1617 		if (cppc_state == AMD_PSTATE_DISABLE)
1618 			pr_info("driver is explicitly disabled\n");
1619 
1620 		if (cppc_state == AMD_PSTATE_ACTIVE)
1621 			current_pstate_driver = &amd_pstate_epp_driver;
1622 
1623 		if (cppc_state == AMD_PSTATE_PASSIVE || cppc_state == AMD_PSTATE_GUIDED)
1624 			current_pstate_driver = &amd_pstate_driver;
1625 
1626 		return 0;
1627 	}
1628 
1629 	return -EINVAL;
1630 }
1631 
1632 static int amd_pstate_register_driver(int mode)
1633 {
1634 	struct freq_attr **attr = NULL;
1635 	int ret;
1636 
1637 	ret = amd_pstate_set_driver(mode);
1638 	if (ret)
1639 		return ret;
1640 
1641 	cppc_state = mode;
1642 
1643 	/*
1644 	 * Note: It is important to compute the attrs _after_
1645 	 * re-initializing the cppc_state.  Some attributes become
1646 	 * visible only when cppc_state is AMD_PSTATE_ACTIVE.
1647 	 */
1648 	attr = get_freq_attrs();
1649 	if (IS_ERR(attr)) {
1650 		ret = (int) PTR_ERR(attr);
1651 		pr_err("Couldn't compute freq_attrs for current mode %s [%d]\n",
1652 			amd_pstate_get_mode_string(cppc_state), ret);
1653 		amd_pstate_driver_cleanup();
1654 		return ret;
1655 	}
1656 
1657 	current_pstate_driver->attr = attr;
1658 
1659 	/* at least one CPU supports CPB */
1660 	current_pstate_driver->boost_enabled = cpu_feature_enabled(X86_FEATURE_CPB);
1661 
1662 	ret = cpufreq_register_driver(current_pstate_driver);
1663 	if (ret) {
1664 		amd_pstate_driver_cleanup();
1665 		return ret;
1666 	}
1667 
1668 	/* Enable ITMT support once all CPUs have initialized their asym priorities. */
1669 	if (amd_pstate_prefcore)
1670 		sched_set_itmt_support();
1671 
1672 	return 0;
1673 }
1674 
1675 static int amd_pstate_unregister_driver(int dummy)
1676 {
1677 	cpufreq_unregister_driver(current_pstate_driver);
1678 	amd_pstate_driver_cleanup();
1679 	return 0;
1680 }
1681 
1682 static int amd_pstate_change_mode_without_dvr_change(int mode)
1683 {
1684 	int cpu = 0;
1685 
1686 	cppc_state = mode;
1687 
1688 	if (cpu_feature_enabled(X86_FEATURE_CPPC) || cppc_state == AMD_PSTATE_ACTIVE)
1689 		return 0;
1690 
1691 	for_each_online_cpu(cpu) {
1692 		cppc_set_auto_sel(cpu, (cppc_state == AMD_PSTATE_PASSIVE) ? 0 : 1);
1693 	}
1694 
1695 	return 0;
1696 }
1697 
1698 static int amd_pstate_change_driver_mode(int mode)
1699 {
1700 	int ret;
1701 
1702 	lockdep_assert_held(&amd_pstate_driver_lock);
1703 
1704 	ret = amd_pstate_unregister_driver(0);
1705 	if (ret)
1706 		return ret;
1707 
1708 	ret = amd_pstate_register_driver(mode);
1709 	if (ret)
1710 		return ret;
1711 
1712 	return 0;
1713 }
1714 
1715 static cppc_mode_transition_fn mode_state_machine[AMD_PSTATE_MAX][AMD_PSTATE_MAX] = {
1716 	[AMD_PSTATE_DISABLE]         = {
1717 		[AMD_PSTATE_DISABLE]     = NULL,
1718 		[AMD_PSTATE_PASSIVE]     = amd_pstate_register_driver,
1719 		[AMD_PSTATE_ACTIVE]      = amd_pstate_register_driver,
1720 		[AMD_PSTATE_GUIDED]      = amd_pstate_register_driver,
1721 	},
1722 	[AMD_PSTATE_PASSIVE]         = {
1723 		[AMD_PSTATE_DISABLE]     = amd_pstate_unregister_driver,
1724 		[AMD_PSTATE_PASSIVE]     = NULL,
1725 		[AMD_PSTATE_ACTIVE]      = amd_pstate_change_driver_mode,
1726 		[AMD_PSTATE_GUIDED]      = amd_pstate_change_mode_without_dvr_change,
1727 	},
1728 	[AMD_PSTATE_ACTIVE]          = {
1729 		[AMD_PSTATE_DISABLE]     = amd_pstate_unregister_driver,
1730 		[AMD_PSTATE_PASSIVE]     = amd_pstate_change_driver_mode,
1731 		[AMD_PSTATE_ACTIVE]      = NULL,
1732 		[AMD_PSTATE_GUIDED]      = amd_pstate_change_driver_mode,
1733 	},
1734 	[AMD_PSTATE_GUIDED]          = {
1735 		[AMD_PSTATE_DISABLE]     = amd_pstate_unregister_driver,
1736 		[AMD_PSTATE_PASSIVE]     = amd_pstate_change_mode_without_dvr_change,
1737 		[AMD_PSTATE_ACTIVE]      = amd_pstate_change_driver_mode,
1738 		[AMD_PSTATE_GUIDED]      = NULL,
1739 	},
1740 };
1741 
1742 static ssize_t amd_pstate_show_status(char *buf)
1743 {
1744 	if (!current_pstate_driver)
1745 		return sysfs_emit(buf, "disable\n");
1746 
1747 	return sysfs_emit(buf, "%s\n", amd_pstate_mode_string[cppc_state]);
1748 }
1749 
1750 int amd_pstate_get_status(void)
1751 {
1752 	return cppc_state;
1753 }
1754 EXPORT_SYMBOL_GPL(amd_pstate_get_status);
1755 
1756 int amd_pstate_update_status(const char *buf, size_t size)
1757 {
1758 	int mode_idx;
1759 
1760 	if (size > strlen("passive") || size < strlen("active"))
1761 		return -EINVAL;
1762 
1763 	mode_idx = get_mode_idx_from_str(buf, size);
1764 	if (mode_idx < 0)
1765 		return mode_idx;
1766 
1767 	if (mode_state_machine[cppc_state][mode_idx]) {
1768 		guard(mutex)(&amd_pstate_driver_lock);
1769 		return mode_state_machine[cppc_state][mode_idx](mode_idx);
1770 	}
1771 
1772 	return 0;
1773 }
1774 EXPORT_SYMBOL_GPL(amd_pstate_update_status);
1775 
1776 static ssize_t status_show(struct device *dev,
1777 			   struct device_attribute *attr, char *buf)
1778 {
1779 
1780 	guard(mutex)(&amd_pstate_driver_lock);
1781 
1782 	return amd_pstate_show_status(buf);
1783 }
1784 
1785 static ssize_t status_store(struct device *a, struct device_attribute *b,
1786 			    const char *buf, size_t count)
1787 {
1788 	char *p = memchr(buf, '\n', count);
1789 	int ret;
1790 
1791 	ret = amd_pstate_update_status(buf, p ? p - buf : count);
1792 
1793 	return ret < 0 ? ret : count;
1794 }
1795 
1796 static ssize_t prefcore_show(struct device *dev,
1797 			     struct device_attribute *attr, char *buf)
1798 {
1799 	return sysfs_emit(buf, "%s\n", str_enabled_disabled(amd_pstate_prefcore));
1800 }
1801 
1802 static ssize_t dynamic_epp_show(struct device *dev,
1803 				struct device_attribute *attr, char *buf)
1804 {
1805 	return sysfs_emit(buf, "%s\n", str_enabled_disabled(dynamic_epp));
1806 }
1807 
1808 static ssize_t dynamic_epp_store(struct device *a, struct device_attribute *b,
1809 				 const char *buf, size_t count)
1810 {
1811 	bool enabled;
1812 	int ret;
1813 
1814 	ret = kstrtobool(buf, &enabled);
1815 	if (ret)
1816 		return ret;
1817 
1818 	guard(mutex)(&amd_pstate_driver_lock);
1819 
1820 	if (cppc_state != AMD_PSTATE_ACTIVE) {
1821 		pr_debug("dynamic_epp can only be toggled in active mode\n");
1822 		return -EINVAL;
1823 	}
1824 
1825 	/* Nothing to do */
1826 	if (dynamic_epp == enabled)
1827 		return count;
1828 
1829 	/* reinitialize with desired dynamic EPP value */
1830 	dynamic_epp = enabled;
1831 	ret = amd_pstate_change_driver_mode(cppc_state);
1832 	if (ret)
1833 		dynamic_epp = false;
1834 
1835 	return ret ? ret : count;
1836 }
1837 
1838 static DEVICE_ATTR_RW(status);
1839 static DEVICE_ATTR_RO(prefcore);
1840 static DEVICE_ATTR_RW(dynamic_epp);
1841 
1842 static struct attribute *pstate_global_attributes[] = {
1843 	&dev_attr_status.attr,
1844 	&dev_attr_prefcore.attr,
1845 	&dev_attr_dynamic_epp.attr,
1846 	NULL
1847 };
1848 
1849 static const struct attribute_group amd_pstate_global_attr_group = {
1850 	.name = "amd_pstate",
1851 	.attrs = pstate_global_attributes,
1852 };
1853 
1854 static bool amd_pstate_acpi_pm_profile_server(void)
1855 {
1856 	switch (acpi_gbl_FADT.preferred_profile) {
1857 	case PM_ENTERPRISE_SERVER:
1858 	case PM_SOHO_SERVER:
1859 	case PM_PERFORMANCE_SERVER:
1860 		return true;
1861 	}
1862 	return false;
1863 }
1864 
1865 static bool amd_pstate_acpi_pm_profile_undefined(void)
1866 {
1867 	if (acpi_gbl_FADT.preferred_profile == PM_UNSPECIFIED)
1868 		return true;
1869 	if (acpi_gbl_FADT.preferred_profile >= NR_PM_PROFILES)
1870 		return true;
1871 	return false;
1872 }
1873 
1874 static int amd_pstate_epp_cpu_init(struct cpufreq_policy *policy)
1875 {
1876 	struct amd_cpudata *cpudata;
1877 	union perf_cached perf;
1878 	struct device *dev;
1879 	int ret;
1880 
1881 	/*
1882 	 * Resetting PERF_CTL_MSR will put the CPU in P0 frequency,
1883 	 * which is ideal for initialization process.
1884 	 */
1885 	amd_perf_ctl_reset(policy->cpu);
1886 	dev = get_cpu_device(policy->cpu);
1887 	if (!dev)
1888 		return -ENODEV;
1889 
1890 	cpudata = kzalloc_obj(*cpudata);
1891 	if (!cpudata)
1892 		return -ENOMEM;
1893 
1894 	cpudata->cpu = policy->cpu;
1895 
1896 	ret = amd_pstate_init_perf(cpudata);
1897 	if (ret)
1898 		goto free_cpudata1;
1899 
1900 	amd_pstate_init_prefcore(cpudata);
1901 
1902 	ret = amd_pstate_init_freq(cpudata);
1903 	if (ret)
1904 		goto free_cpudata1;
1905 
1906 	ret = amd_pstate_init_boost_support(cpudata);
1907 	if (ret)
1908 		goto free_cpudata1;
1909 
1910 	perf = READ_ONCE(cpudata->perf);
1911 
1912 	policy->cpuinfo.min_freq = perf_to_freq(perf, cpudata->nominal_freq,
1913 						perf.lowest_perf);
1914 	policy->cpuinfo.max_freq = cpudata->max_freq;
1915 	policy->driver_data = cpudata;
1916 
1917 	ret = amd_pstate_cppc_enable(policy);
1918 	if (ret)
1919 		goto free_cpudata1;
1920 
1921 	/* It will be updated by governor */
1922 	policy->cur = policy->cpuinfo.min_freq;
1923 
1924 
1925 	policy->boost_supported = READ_ONCE(cpudata->boost_supported);
1926 
1927 	/*
1928 	 * Set the policy to provide a valid fallback value in case
1929 	 * the default cpufreq governor is neither powersave nor performance.
1930 	 */
1931 	if (amd_pstate_acpi_pm_profile_server() ||
1932 	    amd_pstate_acpi_pm_profile_undefined()) {
1933 		policy->policy = CPUFREQ_POLICY_PERFORMANCE;
1934 		cpudata->epp_default_ac = cpudata->epp_default_dc = amd_pstate_get_epp(cpudata);
1935 		cpudata->current_profile = PLATFORM_PROFILE_PERFORMANCE;
1936 	} else {
1937 		policy->policy = CPUFREQ_POLICY_POWERSAVE;
1938 		cpudata->epp_default_ac = AMD_CPPC_EPP_PERFORMANCE;
1939 		cpudata->epp_default_dc = AMD_CPPC_EPP_BALANCE_PERFORMANCE;
1940 		cpudata->current_profile = PLATFORM_PROFILE_BALANCED;
1941 	}
1942 
1943 	if (dynamic_epp)
1944 		ret = amd_pstate_set_dynamic_epp(policy);
1945 	else
1946 		ret = amd_pstate_set_epp(policy, cpudata->epp_default_dc);
1947 	if (ret)
1948 		goto free_cpudata1;
1949 
1950 	ret = amd_pstate_init_floor_perf(policy);
1951 	if (ret) {
1952 		dev_err(dev, "Failed to initialize Floor Perf (%d)\n", ret);
1953 		goto free_cpudata1;
1954 	}
1955 
1956 	current_pstate_driver->adjust_perf = NULL;
1957 
1958 	return 0;
1959 
1960 free_cpudata1:
1961 	pr_warn("Failed to initialize CPU %d: %d\n", policy->cpu, ret);
1962 	kfree(cpudata);
1963 	policy->driver_data = NULL;
1964 	return ret;
1965 }
1966 
1967 static void amd_pstate_epp_cpu_exit(struct cpufreq_policy *policy)
1968 {
1969 	struct amd_cpudata *cpudata = policy->driver_data;
1970 
1971 	if (cpudata) {
1972 		union perf_cached perf = READ_ONCE(cpudata->perf);
1973 
1974 		if (cpudata->dynamic_epp)
1975 			amd_pstate_clear_dynamic_epp(policy);
1976 
1977 		/* Reset CPPC_REQ MSR to the BIOS value */
1978 		amd_pstate_update_perf(policy, perf.bios_min_perf, 0U, 0U, 0U, false);
1979 		amd_pstate_set_floor_perf(policy, cpudata->bios_floor_perf);
1980 
1981 		kfree(cpudata);
1982 		policy->driver_data = NULL;
1983 	}
1984 
1985 	pr_debug("CPU %d exiting\n", policy->cpu);
1986 }
1987 
1988 static int amd_pstate_epp_update_limit(struct cpufreq_policy *policy, bool policy_change)
1989 {
1990 	struct amd_cpudata *cpudata = policy->driver_data;
1991 	union perf_cached perf;
1992 	u8 epp;
1993 
1994 	if (policy_change ||
1995 	    policy->min != cpudata->min_limit_freq ||
1996 	    policy->max != cpudata->max_limit_freq)
1997 		amd_pstate_update_min_max_limit(policy);
1998 
1999 	if (cpudata->policy == CPUFREQ_POLICY_PERFORMANCE)
2000 		epp = 0;
2001 	else
2002 		epp = FIELD_GET(AMD_CPPC_EPP_PERF_MASK, cpudata->cppc_req_cached);
2003 
2004 	perf = READ_ONCE(cpudata->perf);
2005 
2006 	return amd_pstate_update_perf(policy, perf.min_limit_perf, 0U,
2007 				      perf.max_limit_perf, epp, false);
2008 }
2009 
2010 static int amd_pstate_epp_set_policy(struct cpufreq_policy *policy)
2011 {
2012 	struct amd_cpudata *cpudata = policy->driver_data;
2013 	int ret;
2014 
2015 	if (!policy->cpuinfo.max_freq)
2016 		return -ENODEV;
2017 
2018 	cpudata->policy = policy->policy;
2019 
2020 	ret = amd_pstate_epp_update_limit(policy, true);
2021 	if (ret)
2022 		return ret;
2023 
2024 	/*
2025 	 * policy->cur is never updated with the amd_pstate_epp driver, but it
2026 	 * is used as a stale frequency value. So, keep it within limits.
2027 	 */
2028 	policy->cur = policy->min;
2029 
2030 	return 0;
2031 }
2032 
2033 static int amd_pstate_cpu_online(struct cpufreq_policy *policy)
2034 {
2035 	struct amd_cpudata *cpudata = policy->driver_data;
2036 	union perf_cached perf = READ_ONCE(cpudata->perf);
2037 	u8 cached_floor_perf;
2038 	int ret;
2039 
2040 	ret = amd_pstate_cppc_enable(policy);
2041 	if (ret)
2042 		return ret;
2043 
2044 	cached_floor_perf = freq_to_perf(perf, cpudata->nominal_freq, cpudata->floor_freq);
2045 	return amd_pstate_set_floor_perf(policy, cached_floor_perf);
2046 }
2047 
2048 static int amd_pstate_cpu_offline(struct cpufreq_policy *policy)
2049 {
2050 	struct amd_cpudata *cpudata = policy->driver_data;
2051 	union perf_cached perf = READ_ONCE(cpudata->perf);
2052 	int ret;
2053 
2054 	/*
2055 	 * Reset CPPC_REQ MSR to the BIOS value, this will allow us to retain the BIOS specified
2056 	 * min_perf value across kexec reboots. If this CPU is just onlined normally after this, the
2057 	 * limits, epp and desired perf will get reset to the cached values in cpudata struct
2058 	 */
2059 	ret = amd_pstate_update_perf(policy, perf.bios_min_perf,
2060 				     FIELD_GET(AMD_CPPC_DES_PERF_MASK, cpudata->cppc_req_cached),
2061 				     FIELD_GET(AMD_CPPC_MAX_PERF_MASK, cpudata->cppc_req_cached),
2062 				     FIELD_GET(AMD_CPPC_EPP_PERF_MASK, cpudata->cppc_req_cached),
2063 				     false);
2064 	if (ret)
2065 		return ret;
2066 
2067 	return amd_pstate_set_floor_perf(policy, cpudata->bios_floor_perf);
2068 }
2069 
2070 static int amd_pstate_suspend(struct cpufreq_policy *policy)
2071 {
2072 	struct amd_cpudata *cpudata = policy->driver_data;
2073 	union perf_cached perf = READ_ONCE(cpudata->perf);
2074 	int ret;
2075 
2076 	/*
2077 	 * Reset CPPC_REQ MSR to the BIOS value, this will allow us to retain the BIOS specified
2078 	 * min_perf value across kexec reboots. If this CPU is just resumed back without kexec,
2079 	 * the limits, epp and desired perf will get reset to the cached values in cpudata struct
2080 	 */
2081 	ret = amd_pstate_update_perf(policy, perf.bios_min_perf,
2082 				     FIELD_GET(AMD_CPPC_DES_PERF_MASK, cpudata->cppc_req_cached),
2083 				     FIELD_GET(AMD_CPPC_MAX_PERF_MASK, cpudata->cppc_req_cached),
2084 				     FIELD_GET(AMD_CPPC_EPP_PERF_MASK, cpudata->cppc_req_cached),
2085 				     false);
2086 	if (ret)
2087 		return ret;
2088 
2089 	ret = amd_pstate_set_floor_perf(policy, cpudata->bios_floor_perf);
2090 	if (ret)
2091 		return ret;
2092 
2093 	/* set this flag to avoid setting core offline*/
2094 	cpudata->suspended = true;
2095 
2096 	return 0;
2097 }
2098 
2099 static int amd_pstate_resume(struct cpufreq_policy *policy)
2100 {
2101 	struct amd_cpudata *cpudata = policy->driver_data;
2102 	union perf_cached perf = READ_ONCE(cpudata->perf);
2103 	int cur_perf = freq_to_perf(perf, cpudata->nominal_freq, policy->cur);
2104 	u8 cached_floor_perf;
2105 	int ret;
2106 
2107 	/* Set CPPC_REQ to last sane value until the governor updates it */
2108 	ret = amd_pstate_update_perf(policy, perf.min_limit_perf, cur_perf, perf.max_limit_perf,
2109 				     0U, false);
2110 	if (ret)
2111 		return ret;
2112 
2113 	cached_floor_perf = freq_to_perf(perf, cpudata->nominal_freq, cpudata->floor_freq);
2114 	return amd_pstate_set_floor_perf(policy, cached_floor_perf);
2115 }
2116 
2117 static int amd_pstate_epp_resume(struct cpufreq_policy *policy)
2118 {
2119 	struct amd_cpudata *cpudata = policy->driver_data;
2120 	union perf_cached perf = READ_ONCE(cpudata->perf);
2121 	u8 cached_floor_perf;
2122 
2123 	if (cpudata->suspended) {
2124 		int ret;
2125 
2126 		/* enable amd pstate from suspend state*/
2127 		ret = amd_pstate_epp_update_limit(policy, false);
2128 		if (ret)
2129 			return ret;
2130 
2131 		cpudata->suspended = false;
2132 	}
2133 
2134 	cached_floor_perf = freq_to_perf(perf, cpudata->nominal_freq, cpudata->floor_freq);
2135 	return amd_pstate_set_floor_perf(policy, cached_floor_perf);
2136 }
2137 
2138 static struct cpufreq_driver amd_pstate_driver = {
2139 	.flags		= CPUFREQ_CONST_LOOPS | CPUFREQ_NEED_UPDATE_LIMITS,
2140 	.verify		= amd_pstate_verify,
2141 	.target		= amd_pstate_target,
2142 	.fast_switch    = amd_pstate_fast_switch,
2143 	.init		= amd_pstate_cpu_init,
2144 	.exit		= amd_pstate_cpu_exit,
2145 	.online		= amd_pstate_cpu_online,
2146 	.offline	= amd_pstate_cpu_offline,
2147 	.suspend	= amd_pstate_suspend,
2148 	.resume		= amd_pstate_resume,
2149 	.set_boost	= amd_pstate_set_boost,
2150 	.update_limits	= amd_pstate_update_limits,
2151 	.name		= "amd-pstate",
2152 };
2153 
2154 static struct cpufreq_driver amd_pstate_epp_driver = {
2155 	.flags		= CPUFREQ_CONST_LOOPS,
2156 	.verify		= amd_pstate_verify,
2157 	.setpolicy	= amd_pstate_epp_set_policy,
2158 	.init		= amd_pstate_epp_cpu_init,
2159 	.exit		= amd_pstate_epp_cpu_exit,
2160 	.offline	= amd_pstate_cpu_offline,
2161 	.online		= amd_pstate_cpu_online,
2162 	.suspend	= amd_pstate_suspend,
2163 	.resume		= amd_pstate_epp_resume,
2164 	.update_limits	= amd_pstate_update_limits,
2165 	.set_boost	= amd_pstate_set_boost,
2166 	.name		= "amd-pstate-epp",
2167 };
2168 
2169 /*
2170  * CPPC function is not supported for family ID 17H with model_ID ranging from 0x10 to 0x2F.
2171  * show the debug message that helps to check if the CPU has CPPC support for loading issue.
2172  */
2173 static bool amd_cppc_supported(void)
2174 {
2175 	struct cpuinfo_x86 *c = &cpu_data(0);
2176 	bool warn = false;
2177 
2178 	if ((boot_cpu_data.x86 == 0x17) && (boot_cpu_data.x86_model < 0x30)) {
2179 		pr_debug_once("CPPC feature is not supported by the processor\n");
2180 		return false;
2181 	}
2182 
2183 	/*
2184 	 * If the CPPC feature is disabled in the BIOS for processors
2185 	 * that support MSR-based CPPC, the AMD Pstate driver may not
2186 	 * function correctly.
2187 	 *
2188 	 * For such processors, check the CPPC flag and display a
2189 	 * warning message if the platform supports CPPC.
2190 	 *
2191 	 * Note: The code check below will not abort the driver
2192 	 * registration process because of the code is added for
2193 	 * debugging purposes. Besides, it may still be possible for
2194 	 * the driver to work using the shared-memory mechanism.
2195 	 */
2196 	if (!cpu_feature_enabled(X86_FEATURE_CPPC)) {
2197 		if (cpu_feature_enabled(X86_FEATURE_ZEN2)) {
2198 			switch (c->x86_model) {
2199 			case 0x60 ... 0x6F:
2200 			case 0x80 ... 0xAF:
2201 				warn = true;
2202 				break;
2203 			}
2204 		} else if (cpu_feature_enabled(X86_FEATURE_ZEN3) ||
2205 			   cpu_feature_enabled(X86_FEATURE_ZEN4)) {
2206 			switch (c->x86_model) {
2207 			case 0x10 ... 0x1F:
2208 			case 0x40 ... 0xAF:
2209 				warn = true;
2210 				break;
2211 			}
2212 		} else if (cpu_feature_enabled(X86_FEATURE_ZEN5)) {
2213 			warn = true;
2214 		}
2215 	}
2216 
2217 	if (warn)
2218 		pr_warn_once("The CPPC feature is supported but currently disabled by the BIOS.\n"
2219 					"Please enable it if your BIOS has the CPPC option.\n");
2220 	return true;
2221 }
2222 
2223 static int __init amd_pstate_init(void)
2224 {
2225 	struct device *dev_root;
2226 	int ret;
2227 
2228 	if (boot_cpu_data.x86_vendor != X86_VENDOR_AMD)
2229 		return -ENODEV;
2230 
2231 	/* show debug message only if CPPC is not supported */
2232 	if (!amd_cppc_supported())
2233 		return -EOPNOTSUPP;
2234 
2235 	/* show warning message when BIOS broken or ACPI disabled */
2236 	if (!acpi_cpc_valid()) {
2237 		pr_warn_once("the _CPC object is not present in SBIOS or ACPI disabled\n");
2238 		return -ENODEV;
2239 	}
2240 
2241 	/* don't keep reloading if cpufreq_driver exists */
2242 	if (cpufreq_get_current_driver())
2243 		return -EEXIST;
2244 
2245 	quirks = NULL;
2246 
2247 	/* check if this machine need CPPC quirks */
2248 	dmi_check_system(amd_pstate_quirks_table);
2249 
2250 	/*
2251 	* determine the driver mode from the command line or kernel config.
2252 	* If no command line input is provided, cppc_state will be AMD_PSTATE_UNDEFINED.
2253 	* command line options will override the kernel config settings.
2254 	*/
2255 
2256 	if (cppc_state == AMD_PSTATE_UNDEFINED) {
2257 		/* Disable on the following configs by default:
2258 		 * 1. Undefined platforms
2259 		 * 2. Server platforms with CPUs older than Family 0x1A.
2260 		 */
2261 		if (amd_pstate_acpi_pm_profile_undefined() ||
2262 		    (amd_pstate_acpi_pm_profile_server() && boot_cpu_data.x86 < 0x1A)) {
2263 			pr_info("driver load is disabled, boot with specific mode to enable this\n");
2264 			return -ENODEV;
2265 		}
2266 		/* get driver mode from kernel config option [1:4] */
2267 		cppc_state = CONFIG_X86_AMD_PSTATE_DEFAULT_MODE;
2268 	}
2269 
2270 	if (cppc_state == AMD_PSTATE_DISABLE) {
2271 		pr_info("driver load is disabled, boot with specific mode to enable this\n");
2272 		return -ENODEV;
2273 	}
2274 
2275 	/* capability check */
2276 	if (cpu_feature_enabled(X86_FEATURE_CPPC)) {
2277 		pr_debug("AMD CPPC MSR based functionality is supported\n");
2278 	} else {
2279 		pr_debug("AMD CPPC shared memory based functionality is supported\n");
2280 		static_call_update(amd_pstate_cppc_enable, shmem_cppc_enable);
2281 		static_call_update(amd_pstate_init_perf, shmem_init_perf);
2282 		static_call_update(amd_pstate_update_perf, shmem_update_perf);
2283 		static_call_update(amd_pstate_get_epp, shmem_get_epp);
2284 		static_call_update(amd_pstate_set_epp, shmem_set_epp);
2285 	}
2286 
2287 	if (amd_pstate_prefcore) {
2288 		ret = amd_detect_prefcore(&amd_pstate_prefcore);
2289 		if (ret)
2290 			return ret;
2291 	}
2292 
2293 	ret = amd_pstate_register_driver(cppc_state);
2294 	if (ret) {
2295 		pr_err("failed to register with return %d\n", ret);
2296 		return ret;
2297 	}
2298 
2299 	dev_root = bus_get_dev_root(&cpu_subsys);
2300 	if (dev_root) {
2301 		ret = sysfs_create_group(&dev_root->kobj, &amd_pstate_global_attr_group);
2302 		put_device(dev_root);
2303 		if (ret) {
2304 			pr_err("sysfs attribute export failed with error %d.\n", ret);
2305 			goto global_attr_free;
2306 		}
2307 	}
2308 
2309 	return ret;
2310 
2311 global_attr_free:
2312 	amd_pstate_unregister_driver(0);
2313 	return ret;
2314 }
2315 device_initcall(amd_pstate_init);
2316 
2317 static int __init amd_pstate_param(char *str)
2318 {
2319 	size_t size;
2320 	int mode_idx;
2321 
2322 	if (!str)
2323 		return -EINVAL;
2324 
2325 	size = strlen(str);
2326 	mode_idx = get_mode_idx_from_str(str, size);
2327 
2328 	return amd_pstate_set_driver(mode_idx);
2329 }
2330 
2331 static int __init amd_prefcore_param(char *str)
2332 {
2333 	if (!strcmp(str, "disable"))
2334 		amd_pstate_prefcore = false;
2335 
2336 	return 0;
2337 }
2338 
2339 static int __init amd_dynamic_epp_param(char *str)
2340 {
2341 	if (!strcmp(str, "disable"))
2342 		dynamic_epp = false;
2343 	if (!strcmp(str, "enable"))
2344 		dynamic_epp = true;
2345 
2346 	return 0;
2347 }
2348 
2349 early_param("amd_pstate", amd_pstate_param);
2350 early_param("amd_prefcore", amd_prefcore_param);
2351 early_param("amd_dynamic_epp", amd_dynamic_epp_param);
2352 
2353 MODULE_AUTHOR("Huang Rui <ray.huang@amd.com>");
2354 MODULE_DESCRIPTION("AMD Processor P-state Frequency Driver");
2355