Merge tag 'icc-6.7-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/djakov/icc...
[linux-2.6-microblaze.git] / drivers / cpufreq / amd-pstate.c
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/kernel.h>
26 #include <linux/module.h>
27 #include <linux/init.h>
28 #include <linux/smp.h>
29 #include <linux/sched.h>
30 #include <linux/cpufreq.h>
31 #include <linux/compiler.h>
32 #include <linux/dmi.h>
33 #include <linux/slab.h>
34 #include <linux/acpi.h>
35 #include <linux/io.h>
36 #include <linux/delay.h>
37 #include <linux/uaccess.h>
38 #include <linux/static_call.h>
39 #include <linux/amd-pstate.h>
40
41 #include <acpi/processor.h>
42 #include <acpi/cppc_acpi.h>
43
44 #include <asm/msr.h>
45 #include <asm/processor.h>
46 #include <asm/cpufeature.h>
47 #include <asm/cpu_device_id.h>
48 #include "amd-pstate-trace.h"
49
50 #define AMD_PSTATE_TRANSITION_LATENCY   20000
51 #define AMD_PSTATE_TRANSITION_DELAY     1000
52
53 /*
54  * TODO: We need more time to fine tune processors with shared memory solution
55  * with community together.
56  *
57  * There are some performance drops on the CPU benchmarks which reports from
58  * Suse. We are co-working with them to fine tune the shared memory solution. So
59  * we disable it by default to go acpi-cpufreq on these processors and add a
60  * module parameter to be able to enable it manually for debugging.
61  */
62 static struct cpufreq_driver *current_pstate_driver;
63 static struct cpufreq_driver amd_pstate_driver;
64 static struct cpufreq_driver amd_pstate_epp_driver;
65 static int cppc_state = AMD_PSTATE_UNDEFINED;
66 static bool cppc_enabled;
67
68 /*
69  * AMD Energy Preference Performance (EPP)
70  * The EPP is used in the CCLK DPM controller to drive
71  * the frequency that a core is going to operate during
72  * short periods of activity. EPP values will be utilized for
73  * different OS profiles (balanced, performance, power savings)
74  * display strings corresponding to EPP index in the
75  * energy_perf_strings[]
76  *      index           String
77  *-------------------------------------
78  *      0               default
79  *      1               performance
80  *      2               balance_performance
81  *      3               balance_power
82  *      4               power
83  */
84 enum energy_perf_value_index {
85         EPP_INDEX_DEFAULT = 0,
86         EPP_INDEX_PERFORMANCE,
87         EPP_INDEX_BALANCE_PERFORMANCE,
88         EPP_INDEX_BALANCE_POWERSAVE,
89         EPP_INDEX_POWERSAVE,
90 };
91
92 static const char * const energy_perf_strings[] = {
93         [EPP_INDEX_DEFAULT] = "default",
94         [EPP_INDEX_PERFORMANCE] = "performance",
95         [EPP_INDEX_BALANCE_PERFORMANCE] = "balance_performance",
96         [EPP_INDEX_BALANCE_POWERSAVE] = "balance_power",
97         [EPP_INDEX_POWERSAVE] = "power",
98         NULL
99 };
100
101 static unsigned int epp_values[] = {
102         [EPP_INDEX_DEFAULT] = 0,
103         [EPP_INDEX_PERFORMANCE] = AMD_CPPC_EPP_PERFORMANCE,
104         [EPP_INDEX_BALANCE_PERFORMANCE] = AMD_CPPC_EPP_BALANCE_PERFORMANCE,
105         [EPP_INDEX_BALANCE_POWERSAVE] = AMD_CPPC_EPP_BALANCE_POWERSAVE,
106         [EPP_INDEX_POWERSAVE] = AMD_CPPC_EPP_POWERSAVE,
107  };
108
109 typedef int (*cppc_mode_transition_fn)(int);
110
111 static inline int get_mode_idx_from_str(const char *str, size_t size)
112 {
113         int i;
114
115         for (i=0; i < AMD_PSTATE_MAX; i++) {
116                 if (!strncmp(str, amd_pstate_mode_string[i], size))
117                         return i;
118         }
119         return -EINVAL;
120 }
121
122 static DEFINE_MUTEX(amd_pstate_limits_lock);
123 static DEFINE_MUTEX(amd_pstate_driver_lock);
124
125 static s16 amd_pstate_get_epp(struct amd_cpudata *cpudata, u64 cppc_req_cached)
126 {
127         u64 epp;
128         int ret;
129
130         if (boot_cpu_has(X86_FEATURE_CPPC)) {
131                 if (!cppc_req_cached) {
132                         epp = rdmsrl_on_cpu(cpudata->cpu, MSR_AMD_CPPC_REQ,
133                                         &cppc_req_cached);
134                         if (epp)
135                                 return epp;
136                 }
137                 epp = (cppc_req_cached >> 24) & 0xFF;
138         } else {
139                 ret = cppc_get_epp_perf(cpudata->cpu, &epp);
140                 if (ret < 0) {
141                         pr_debug("Could not retrieve energy perf value (%d)\n", ret);
142                         return -EIO;
143                 }
144         }
145
146         return (s16)(epp & 0xff);
147 }
148
149 static int amd_pstate_get_energy_pref_index(struct amd_cpudata *cpudata)
150 {
151         s16 epp;
152         int index = -EINVAL;
153
154         epp = amd_pstate_get_epp(cpudata, 0);
155         if (epp < 0)
156                 return epp;
157
158         switch (epp) {
159         case AMD_CPPC_EPP_PERFORMANCE:
160                 index = EPP_INDEX_PERFORMANCE;
161                 break;
162         case AMD_CPPC_EPP_BALANCE_PERFORMANCE:
163                 index = EPP_INDEX_BALANCE_PERFORMANCE;
164                 break;
165         case AMD_CPPC_EPP_BALANCE_POWERSAVE:
166                 index = EPP_INDEX_BALANCE_POWERSAVE;
167                 break;
168         case AMD_CPPC_EPP_POWERSAVE:
169                 index = EPP_INDEX_POWERSAVE;
170                 break;
171         default:
172                 break;
173         }
174
175         return index;
176 }
177
178 static int amd_pstate_set_epp(struct amd_cpudata *cpudata, u32 epp)
179 {
180         int ret;
181         struct cppc_perf_ctrls perf_ctrls;
182
183         if (boot_cpu_has(X86_FEATURE_CPPC)) {
184                 u64 value = READ_ONCE(cpudata->cppc_req_cached);
185
186                 value &= ~GENMASK_ULL(31, 24);
187                 value |= (u64)epp << 24;
188                 WRITE_ONCE(cpudata->cppc_req_cached, value);
189
190                 ret = wrmsrl_on_cpu(cpudata->cpu, MSR_AMD_CPPC_REQ, value);
191                 if (!ret)
192                         cpudata->epp_cached = epp;
193         } else {
194                 perf_ctrls.energy_perf = epp;
195                 ret = cppc_set_epp_perf(cpudata->cpu, &perf_ctrls, 1);
196                 if (ret) {
197                         pr_debug("failed to set energy perf value (%d)\n", ret);
198                         return ret;
199                 }
200                 cpudata->epp_cached = epp;
201         }
202
203         return ret;
204 }
205
206 static int amd_pstate_set_energy_pref_index(struct amd_cpudata *cpudata,
207                 int pref_index)
208 {
209         int epp = -EINVAL;
210         int ret;
211
212         if (!pref_index) {
213                 pr_debug("EPP pref_index is invalid\n");
214                 return -EINVAL;
215         }
216
217         if (epp == -EINVAL)
218                 epp = epp_values[pref_index];
219
220         if (epp > 0 && cpudata->policy == CPUFREQ_POLICY_PERFORMANCE) {
221                 pr_debug("EPP cannot be set under performance policy\n");
222                 return -EBUSY;
223         }
224
225         ret = amd_pstate_set_epp(cpudata, epp);
226
227         return ret;
228 }
229
230 static inline int pstate_enable(bool enable)
231 {
232         int ret, cpu;
233         unsigned long logical_proc_id_mask = 0;
234
235         if (enable == cppc_enabled)
236                 return 0;
237
238         for_each_present_cpu(cpu) {
239                 unsigned long logical_id = topology_logical_die_id(cpu);
240
241                 if (test_bit(logical_id, &logical_proc_id_mask))
242                         continue;
243
244                 set_bit(logical_id, &logical_proc_id_mask);
245
246                 ret = wrmsrl_safe_on_cpu(cpu, MSR_AMD_CPPC_ENABLE,
247                                 enable);
248                 if (ret)
249                         return ret;
250         }
251
252         cppc_enabled = enable;
253         return 0;
254 }
255
256 static int cppc_enable(bool enable)
257 {
258         int cpu, ret = 0;
259         struct cppc_perf_ctrls perf_ctrls;
260
261         if (enable == cppc_enabled)
262                 return 0;
263
264         for_each_present_cpu(cpu) {
265                 ret = cppc_set_enable(cpu, enable);
266                 if (ret)
267                         return ret;
268
269                 /* Enable autonomous mode for EPP */
270                 if (cppc_state == AMD_PSTATE_ACTIVE) {
271                         /* Set desired perf as zero to allow EPP firmware control */
272                         perf_ctrls.desired_perf = 0;
273                         ret = cppc_set_perf(cpu, &perf_ctrls);
274                         if (ret)
275                                 return ret;
276                 }
277         }
278
279         cppc_enabled = enable;
280         return ret;
281 }
282
283 DEFINE_STATIC_CALL(amd_pstate_enable, pstate_enable);
284
285 static inline int amd_pstate_enable(bool enable)
286 {
287         return static_call(amd_pstate_enable)(enable);
288 }
289
290 static int pstate_init_perf(struct amd_cpudata *cpudata)
291 {
292         u64 cap1;
293         u32 highest_perf;
294
295         int ret = rdmsrl_safe_on_cpu(cpudata->cpu, MSR_AMD_CPPC_CAP1,
296                                      &cap1);
297         if (ret)
298                 return ret;
299
300         /*
301          * TODO: Introduce AMD specific power feature.
302          *
303          * CPPC entry doesn't indicate the highest performance in some ASICs.
304          */
305         highest_perf = amd_get_highest_perf();
306         if (highest_perf > AMD_CPPC_HIGHEST_PERF(cap1))
307                 highest_perf = AMD_CPPC_HIGHEST_PERF(cap1);
308
309         WRITE_ONCE(cpudata->highest_perf, highest_perf);
310         WRITE_ONCE(cpudata->max_limit_perf, highest_perf);
311         WRITE_ONCE(cpudata->nominal_perf, AMD_CPPC_NOMINAL_PERF(cap1));
312         WRITE_ONCE(cpudata->lowest_nonlinear_perf, AMD_CPPC_LOWNONLIN_PERF(cap1));
313         WRITE_ONCE(cpudata->lowest_perf, AMD_CPPC_LOWEST_PERF(cap1));
314         WRITE_ONCE(cpudata->min_limit_perf, AMD_CPPC_LOWEST_PERF(cap1));
315         return 0;
316 }
317
318 static int cppc_init_perf(struct amd_cpudata *cpudata)
319 {
320         struct cppc_perf_caps cppc_perf;
321         u32 highest_perf;
322
323         int ret = cppc_get_perf_caps(cpudata->cpu, &cppc_perf);
324         if (ret)
325                 return ret;
326
327         highest_perf = amd_get_highest_perf();
328         if (highest_perf > cppc_perf.highest_perf)
329                 highest_perf = cppc_perf.highest_perf;
330
331         WRITE_ONCE(cpudata->highest_perf, highest_perf);
332         WRITE_ONCE(cpudata->max_limit_perf, highest_perf);
333         WRITE_ONCE(cpudata->nominal_perf, cppc_perf.nominal_perf);
334         WRITE_ONCE(cpudata->lowest_nonlinear_perf,
335                    cppc_perf.lowest_nonlinear_perf);
336         WRITE_ONCE(cpudata->lowest_perf, cppc_perf.lowest_perf);
337         WRITE_ONCE(cpudata->min_limit_perf, cppc_perf.lowest_perf);
338
339         if (cppc_state == AMD_PSTATE_ACTIVE)
340                 return 0;
341
342         ret = cppc_get_auto_sel_caps(cpudata->cpu, &cppc_perf);
343         if (ret) {
344                 pr_warn("failed to get auto_sel, ret: %d\n", ret);
345                 return 0;
346         }
347
348         ret = cppc_set_auto_sel(cpudata->cpu,
349                         (cppc_state == AMD_PSTATE_PASSIVE) ? 0 : 1);
350
351         if (ret)
352                 pr_warn("failed to set auto_sel, ret: %d\n", ret);
353
354         return ret;
355 }
356
357 DEFINE_STATIC_CALL(amd_pstate_init_perf, pstate_init_perf);
358
359 static inline int amd_pstate_init_perf(struct amd_cpudata *cpudata)
360 {
361         return static_call(amd_pstate_init_perf)(cpudata);
362 }
363
364 static void pstate_update_perf(struct amd_cpudata *cpudata, u32 min_perf,
365                                u32 des_perf, u32 max_perf, bool fast_switch)
366 {
367         if (fast_switch)
368                 wrmsrl(MSR_AMD_CPPC_REQ, READ_ONCE(cpudata->cppc_req_cached));
369         else
370                 wrmsrl_on_cpu(cpudata->cpu, MSR_AMD_CPPC_REQ,
371                               READ_ONCE(cpudata->cppc_req_cached));
372 }
373
374 static void cppc_update_perf(struct amd_cpudata *cpudata,
375                              u32 min_perf, u32 des_perf,
376                              u32 max_perf, bool fast_switch)
377 {
378         struct cppc_perf_ctrls perf_ctrls;
379
380         perf_ctrls.max_perf = max_perf;
381         perf_ctrls.min_perf = min_perf;
382         perf_ctrls.desired_perf = des_perf;
383
384         cppc_set_perf(cpudata->cpu, &perf_ctrls);
385 }
386
387 DEFINE_STATIC_CALL(amd_pstate_update_perf, pstate_update_perf);
388
389 static inline void amd_pstate_update_perf(struct amd_cpudata *cpudata,
390                                           u32 min_perf, u32 des_perf,
391                                           u32 max_perf, bool fast_switch)
392 {
393         static_call(amd_pstate_update_perf)(cpudata, min_perf, des_perf,
394                                             max_perf, fast_switch);
395 }
396
397 static inline bool amd_pstate_sample(struct amd_cpudata *cpudata)
398 {
399         u64 aperf, mperf, tsc;
400         unsigned long flags;
401
402         local_irq_save(flags);
403         rdmsrl(MSR_IA32_APERF, aperf);
404         rdmsrl(MSR_IA32_MPERF, mperf);
405         tsc = rdtsc();
406
407         if (cpudata->prev.mperf == mperf || cpudata->prev.tsc == tsc) {
408                 local_irq_restore(flags);
409                 return false;
410         }
411
412         local_irq_restore(flags);
413
414         cpudata->cur.aperf = aperf;
415         cpudata->cur.mperf = mperf;
416         cpudata->cur.tsc =  tsc;
417         cpudata->cur.aperf -= cpudata->prev.aperf;
418         cpudata->cur.mperf -= cpudata->prev.mperf;
419         cpudata->cur.tsc -= cpudata->prev.tsc;
420
421         cpudata->prev.aperf = aperf;
422         cpudata->prev.mperf = mperf;
423         cpudata->prev.tsc = tsc;
424
425         cpudata->freq = div64_u64((cpudata->cur.aperf * cpu_khz), cpudata->cur.mperf);
426
427         return true;
428 }
429
430 static void amd_pstate_update(struct amd_cpudata *cpudata, u32 min_perf,
431                               u32 des_perf, u32 max_perf, bool fast_switch, int gov_flags)
432 {
433         u64 prev = READ_ONCE(cpudata->cppc_req_cached);
434         u64 value = prev;
435
436         min_perf = clamp_t(unsigned long, min_perf, cpudata->min_limit_perf,
437                         cpudata->max_limit_perf);
438         max_perf = clamp_t(unsigned long, max_perf, cpudata->min_limit_perf,
439                         cpudata->max_limit_perf);
440         des_perf = clamp_t(unsigned long, des_perf, min_perf, max_perf);
441
442         if ((cppc_state == AMD_PSTATE_GUIDED) && (gov_flags & CPUFREQ_GOV_DYNAMIC_SWITCHING)) {
443                 min_perf = des_perf;
444                 des_perf = 0;
445         }
446
447         value &= ~AMD_CPPC_MIN_PERF(~0L);
448         value |= AMD_CPPC_MIN_PERF(min_perf);
449
450         value &= ~AMD_CPPC_DES_PERF(~0L);
451         value |= AMD_CPPC_DES_PERF(des_perf);
452
453         value &= ~AMD_CPPC_MAX_PERF(~0L);
454         value |= AMD_CPPC_MAX_PERF(max_perf);
455
456         if (trace_amd_pstate_perf_enabled() && amd_pstate_sample(cpudata)) {
457                 trace_amd_pstate_perf(min_perf, des_perf, max_perf, cpudata->freq,
458                         cpudata->cur.mperf, cpudata->cur.aperf, cpudata->cur.tsc,
459                                 cpudata->cpu, (value != prev), fast_switch);
460         }
461
462         if (value == prev)
463                 return;
464
465         WRITE_ONCE(cpudata->cppc_req_cached, value);
466
467         amd_pstate_update_perf(cpudata, min_perf, des_perf,
468                                max_perf, fast_switch);
469 }
470
471 static int amd_pstate_verify(struct cpufreq_policy_data *policy)
472 {
473         cpufreq_verify_within_cpu_limits(policy);
474
475         return 0;
476 }
477
478 static int amd_pstate_update_min_max_limit(struct cpufreq_policy *policy)
479 {
480         u32 max_limit_perf, min_limit_perf;
481         struct amd_cpudata *cpudata = policy->driver_data;
482
483         max_limit_perf = div_u64(policy->max * cpudata->highest_perf, cpudata->max_freq);
484         min_limit_perf = div_u64(policy->min * cpudata->highest_perf, cpudata->max_freq);
485
486         WRITE_ONCE(cpudata->max_limit_perf, max_limit_perf);
487         WRITE_ONCE(cpudata->min_limit_perf, min_limit_perf);
488         WRITE_ONCE(cpudata->max_limit_freq, policy->max);
489         WRITE_ONCE(cpudata->min_limit_freq, policy->min);
490
491         return 0;
492 }
493
494 static int amd_pstate_update_freq(struct cpufreq_policy *policy,
495                                   unsigned int target_freq, bool fast_switch)
496 {
497         struct cpufreq_freqs freqs;
498         struct amd_cpudata *cpudata = policy->driver_data;
499         unsigned long max_perf, min_perf, des_perf, cap_perf;
500
501         if (!cpudata->max_freq)
502                 return -ENODEV;
503
504         if (policy->min != cpudata->min_limit_freq || policy->max != cpudata->max_limit_freq)
505                 amd_pstate_update_min_max_limit(policy);
506
507         cap_perf = READ_ONCE(cpudata->highest_perf);
508         min_perf = READ_ONCE(cpudata->lowest_perf);
509         max_perf = cap_perf;
510
511         freqs.old = policy->cur;
512         freqs.new = target_freq;
513
514         des_perf = DIV_ROUND_CLOSEST(target_freq * cap_perf,
515                                      cpudata->max_freq);
516
517         WARN_ON(fast_switch && !policy->fast_switch_enabled);
518         /*
519          * If fast_switch is desired, then there aren't any registered
520          * transition notifiers. See comment for
521          * cpufreq_enable_fast_switch().
522          */
523         if (!fast_switch)
524                 cpufreq_freq_transition_begin(policy, &freqs);
525
526         amd_pstate_update(cpudata, min_perf, des_perf,
527                         max_perf, fast_switch, policy->governor->flags);
528
529         if (!fast_switch)
530                 cpufreq_freq_transition_end(policy, &freqs, false);
531
532         return 0;
533 }
534
535 static int amd_pstate_target(struct cpufreq_policy *policy,
536                              unsigned int target_freq,
537                              unsigned int relation)
538 {
539         return amd_pstate_update_freq(policy, target_freq, false);
540 }
541
542 static unsigned int amd_pstate_fast_switch(struct cpufreq_policy *policy,
543                                   unsigned int target_freq)
544 {
545         if (!amd_pstate_update_freq(policy, target_freq, true))
546                 return target_freq;
547         return policy->cur;
548 }
549
550 static void amd_pstate_adjust_perf(unsigned int cpu,
551                                    unsigned long _min_perf,
552                                    unsigned long target_perf,
553                                    unsigned long capacity)
554 {
555         unsigned long max_perf, min_perf, des_perf,
556                       cap_perf, lowest_nonlinear_perf, max_freq;
557         struct cpufreq_policy *policy = cpufreq_cpu_get(cpu);
558         struct amd_cpudata *cpudata = policy->driver_data;
559         unsigned int target_freq;
560
561         if (policy->min != cpudata->min_limit_freq || policy->max != cpudata->max_limit_freq)
562                 amd_pstate_update_min_max_limit(policy);
563
564
565         cap_perf = READ_ONCE(cpudata->highest_perf);
566         lowest_nonlinear_perf = READ_ONCE(cpudata->lowest_nonlinear_perf);
567         max_freq = READ_ONCE(cpudata->max_freq);
568
569         des_perf = cap_perf;
570         if (target_perf < capacity)
571                 des_perf = DIV_ROUND_UP(cap_perf * target_perf, capacity);
572
573         min_perf = READ_ONCE(cpudata->highest_perf);
574         if (_min_perf < capacity)
575                 min_perf = DIV_ROUND_UP(cap_perf * _min_perf, capacity);
576
577         if (min_perf < lowest_nonlinear_perf)
578                 min_perf = lowest_nonlinear_perf;
579
580         max_perf = cap_perf;
581         if (max_perf < min_perf)
582                 max_perf = min_perf;
583
584         des_perf = clamp_t(unsigned long, des_perf, min_perf, max_perf);
585         target_freq = div_u64(des_perf * max_freq, max_perf);
586         policy->cur = target_freq;
587
588         amd_pstate_update(cpudata, min_perf, des_perf, max_perf, true,
589                         policy->governor->flags);
590         cpufreq_cpu_put(policy);
591 }
592
593 static int amd_get_min_freq(struct amd_cpudata *cpudata)
594 {
595         struct cppc_perf_caps cppc_perf;
596
597         int ret = cppc_get_perf_caps(cpudata->cpu, &cppc_perf);
598         if (ret)
599                 return ret;
600
601         /* Switch to khz */
602         return cppc_perf.lowest_freq * 1000;
603 }
604
605 static int amd_get_max_freq(struct amd_cpudata *cpudata)
606 {
607         struct cppc_perf_caps cppc_perf;
608         u32 max_perf, max_freq, nominal_freq, nominal_perf;
609         u64 boost_ratio;
610
611         int ret = cppc_get_perf_caps(cpudata->cpu, &cppc_perf);
612         if (ret)
613                 return ret;
614
615         nominal_freq = cppc_perf.nominal_freq;
616         nominal_perf = READ_ONCE(cpudata->nominal_perf);
617         max_perf = READ_ONCE(cpudata->highest_perf);
618
619         boost_ratio = div_u64(max_perf << SCHED_CAPACITY_SHIFT,
620                               nominal_perf);
621
622         max_freq = nominal_freq * boost_ratio >> SCHED_CAPACITY_SHIFT;
623
624         /* Switch to khz */
625         return max_freq * 1000;
626 }
627
628 static int amd_get_nominal_freq(struct amd_cpudata *cpudata)
629 {
630         struct cppc_perf_caps cppc_perf;
631
632         int ret = cppc_get_perf_caps(cpudata->cpu, &cppc_perf);
633         if (ret)
634                 return ret;
635
636         /* Switch to khz */
637         return cppc_perf.nominal_freq * 1000;
638 }
639
640 static int amd_get_lowest_nonlinear_freq(struct amd_cpudata *cpudata)
641 {
642         struct cppc_perf_caps cppc_perf;
643         u32 lowest_nonlinear_freq, lowest_nonlinear_perf,
644             nominal_freq, nominal_perf;
645         u64 lowest_nonlinear_ratio;
646
647         int ret = cppc_get_perf_caps(cpudata->cpu, &cppc_perf);
648         if (ret)
649                 return ret;
650
651         nominal_freq = cppc_perf.nominal_freq;
652         nominal_perf = READ_ONCE(cpudata->nominal_perf);
653
654         lowest_nonlinear_perf = cppc_perf.lowest_nonlinear_perf;
655
656         lowest_nonlinear_ratio = div_u64(lowest_nonlinear_perf << SCHED_CAPACITY_SHIFT,
657                                          nominal_perf);
658
659         lowest_nonlinear_freq = nominal_freq * lowest_nonlinear_ratio >> SCHED_CAPACITY_SHIFT;
660
661         /* Switch to khz */
662         return lowest_nonlinear_freq * 1000;
663 }
664
665 static int amd_pstate_set_boost(struct cpufreq_policy *policy, int state)
666 {
667         struct amd_cpudata *cpudata = policy->driver_data;
668         int ret;
669
670         if (!cpudata->boost_supported) {
671                 pr_err("Boost mode is not supported by this processor or SBIOS\n");
672                 return -EINVAL;
673         }
674
675         if (state)
676                 policy->cpuinfo.max_freq = cpudata->max_freq;
677         else
678                 policy->cpuinfo.max_freq = cpudata->nominal_freq;
679
680         policy->max = policy->cpuinfo.max_freq;
681
682         ret = freq_qos_update_request(&cpudata->req[1],
683                                       policy->cpuinfo.max_freq);
684         if (ret < 0)
685                 return ret;
686
687         return 0;
688 }
689
690 static void amd_pstate_boost_init(struct amd_cpudata *cpudata)
691 {
692         u32 highest_perf, nominal_perf;
693
694         highest_perf = READ_ONCE(cpudata->highest_perf);
695         nominal_perf = READ_ONCE(cpudata->nominal_perf);
696
697         if (highest_perf <= nominal_perf)
698                 return;
699
700         cpudata->boost_supported = true;
701         current_pstate_driver->boost_enabled = true;
702 }
703
704 static void amd_perf_ctl_reset(unsigned int cpu)
705 {
706         wrmsrl_on_cpu(cpu, MSR_AMD_PERF_CTL, 0);
707 }
708
709 static int amd_pstate_cpu_init(struct cpufreq_policy *policy)
710 {
711         int min_freq, max_freq, nominal_freq, lowest_nonlinear_freq, ret;
712         struct device *dev;
713         struct amd_cpudata *cpudata;
714
715         /*
716          * Resetting PERF_CTL_MSR will put the CPU in P0 frequency,
717          * which is ideal for initialization process.
718          */
719         amd_perf_ctl_reset(policy->cpu);
720         dev = get_cpu_device(policy->cpu);
721         if (!dev)
722                 return -ENODEV;
723
724         cpudata = kzalloc(sizeof(*cpudata), GFP_KERNEL);
725         if (!cpudata)
726                 return -ENOMEM;
727
728         cpudata->cpu = policy->cpu;
729
730         ret = amd_pstate_init_perf(cpudata);
731         if (ret)
732                 goto free_cpudata1;
733
734         min_freq = amd_get_min_freq(cpudata);
735         max_freq = amd_get_max_freq(cpudata);
736         nominal_freq = amd_get_nominal_freq(cpudata);
737         lowest_nonlinear_freq = amd_get_lowest_nonlinear_freq(cpudata);
738
739         if (min_freq < 0 || max_freq < 0 || min_freq > max_freq) {
740                 dev_err(dev, "min_freq(%d) or max_freq(%d) value is incorrect\n",
741                         min_freq, max_freq);
742                 ret = -EINVAL;
743                 goto free_cpudata1;
744         }
745
746         policy->cpuinfo.transition_latency = AMD_PSTATE_TRANSITION_LATENCY;
747         policy->transition_delay_us = AMD_PSTATE_TRANSITION_DELAY;
748
749         policy->min = min_freq;
750         policy->max = max_freq;
751
752         policy->cpuinfo.min_freq = min_freq;
753         policy->cpuinfo.max_freq = max_freq;
754
755         /* It will be updated by governor */
756         policy->cur = policy->cpuinfo.min_freq;
757
758         if (boot_cpu_has(X86_FEATURE_CPPC))
759                 policy->fast_switch_possible = true;
760
761         ret = freq_qos_add_request(&policy->constraints, &cpudata->req[0],
762                                    FREQ_QOS_MIN, policy->cpuinfo.min_freq);
763         if (ret < 0) {
764                 dev_err(dev, "Failed to add min-freq constraint (%d)\n", ret);
765                 goto free_cpudata1;
766         }
767
768         ret = freq_qos_add_request(&policy->constraints, &cpudata->req[1],
769                                    FREQ_QOS_MAX, policy->cpuinfo.max_freq);
770         if (ret < 0) {
771                 dev_err(dev, "Failed to add max-freq constraint (%d)\n", ret);
772                 goto free_cpudata2;
773         }
774
775         /* Initial processor data capability frequencies */
776         cpudata->max_freq = max_freq;
777         cpudata->min_freq = min_freq;
778         cpudata->max_limit_freq = max_freq;
779         cpudata->min_limit_freq = min_freq;
780         cpudata->nominal_freq = nominal_freq;
781         cpudata->lowest_nonlinear_freq = lowest_nonlinear_freq;
782
783         policy->driver_data = cpudata;
784
785         amd_pstate_boost_init(cpudata);
786         if (!current_pstate_driver->adjust_perf)
787                 current_pstate_driver->adjust_perf = amd_pstate_adjust_perf;
788
789         return 0;
790
791 free_cpudata2:
792         freq_qos_remove_request(&cpudata->req[0]);
793 free_cpudata1:
794         kfree(cpudata);
795         return ret;
796 }
797
798 static int amd_pstate_cpu_exit(struct cpufreq_policy *policy)
799 {
800         struct amd_cpudata *cpudata = policy->driver_data;
801
802         freq_qos_remove_request(&cpudata->req[1]);
803         freq_qos_remove_request(&cpudata->req[0]);
804         policy->fast_switch_possible = false;
805         kfree(cpudata);
806
807         return 0;
808 }
809
810 static int amd_pstate_cpu_resume(struct cpufreq_policy *policy)
811 {
812         int ret;
813
814         ret = amd_pstate_enable(true);
815         if (ret)
816                 pr_err("failed to enable amd-pstate during resume, return %d\n", ret);
817
818         return ret;
819 }
820
821 static int amd_pstate_cpu_suspend(struct cpufreq_policy *policy)
822 {
823         int ret;
824
825         ret = amd_pstate_enable(false);
826         if (ret)
827                 pr_err("failed to disable amd-pstate during suspend, return %d\n", ret);
828
829         return ret;
830 }
831
832 /* Sysfs attributes */
833
834 /*
835  * This frequency is to indicate the maximum hardware frequency.
836  * If boost is not active but supported, the frequency will be larger than the
837  * one in cpuinfo.
838  */
839 static ssize_t show_amd_pstate_max_freq(struct cpufreq_policy *policy,
840                                         char *buf)
841 {
842         int max_freq;
843         struct amd_cpudata *cpudata = policy->driver_data;
844
845         max_freq = amd_get_max_freq(cpudata);
846         if (max_freq < 0)
847                 return max_freq;
848
849         return sysfs_emit(buf, "%u\n", max_freq);
850 }
851
852 static ssize_t show_amd_pstate_lowest_nonlinear_freq(struct cpufreq_policy *policy,
853                                                      char *buf)
854 {
855         int freq;
856         struct amd_cpudata *cpudata = policy->driver_data;
857
858         freq = amd_get_lowest_nonlinear_freq(cpudata);
859         if (freq < 0)
860                 return freq;
861
862         return sysfs_emit(buf, "%u\n", freq);
863 }
864
865 /*
866  * In some of ASICs, the highest_perf is not the one in the _CPC table, so we
867  * need to expose it to sysfs.
868  */
869 static ssize_t show_amd_pstate_highest_perf(struct cpufreq_policy *policy,
870                                             char *buf)
871 {
872         u32 perf;
873         struct amd_cpudata *cpudata = policy->driver_data;
874
875         perf = READ_ONCE(cpudata->highest_perf);
876
877         return sysfs_emit(buf, "%u\n", perf);
878 }
879
880 static ssize_t show_energy_performance_available_preferences(
881                                 struct cpufreq_policy *policy, char *buf)
882 {
883         int i = 0;
884         int offset = 0;
885         struct amd_cpudata *cpudata = policy->driver_data;
886
887         if (cpudata->policy == CPUFREQ_POLICY_PERFORMANCE)
888                 return sysfs_emit_at(buf, offset, "%s\n",
889                                 energy_perf_strings[EPP_INDEX_PERFORMANCE]);
890
891         while (energy_perf_strings[i] != NULL)
892                 offset += sysfs_emit_at(buf, offset, "%s ", energy_perf_strings[i++]);
893
894         offset += sysfs_emit_at(buf, offset, "\n");
895
896         return offset;
897 }
898
899 static ssize_t store_energy_performance_preference(
900                 struct cpufreq_policy *policy, const char *buf, size_t count)
901 {
902         struct amd_cpudata *cpudata = policy->driver_data;
903         char str_preference[21];
904         ssize_t ret;
905
906         ret = sscanf(buf, "%20s", str_preference);
907         if (ret != 1)
908                 return -EINVAL;
909
910         ret = match_string(energy_perf_strings, -1, str_preference);
911         if (ret < 0)
912                 return -EINVAL;
913
914         mutex_lock(&amd_pstate_limits_lock);
915         ret = amd_pstate_set_energy_pref_index(cpudata, ret);
916         mutex_unlock(&amd_pstate_limits_lock);
917
918         return ret ?: count;
919 }
920
921 static ssize_t show_energy_performance_preference(
922                                 struct cpufreq_policy *policy, char *buf)
923 {
924         struct amd_cpudata *cpudata = policy->driver_data;
925         int preference;
926
927         preference = amd_pstate_get_energy_pref_index(cpudata);
928         if (preference < 0)
929                 return preference;
930
931         return sysfs_emit(buf, "%s\n", energy_perf_strings[preference]);
932 }
933
934 static void amd_pstate_driver_cleanup(void)
935 {
936         amd_pstate_enable(false);
937         cppc_state = AMD_PSTATE_DISABLE;
938         current_pstate_driver = NULL;
939 }
940
941 static int amd_pstate_register_driver(int mode)
942 {
943         int ret;
944
945         if (mode == AMD_PSTATE_PASSIVE || mode == AMD_PSTATE_GUIDED)
946                 current_pstate_driver = &amd_pstate_driver;
947         else if (mode == AMD_PSTATE_ACTIVE)
948                 current_pstate_driver = &amd_pstate_epp_driver;
949         else
950                 return -EINVAL;
951
952         cppc_state = mode;
953         ret = cpufreq_register_driver(current_pstate_driver);
954         if (ret) {
955                 amd_pstate_driver_cleanup();
956                 return ret;
957         }
958         return 0;
959 }
960
961 static int amd_pstate_unregister_driver(int dummy)
962 {
963         cpufreq_unregister_driver(current_pstate_driver);
964         amd_pstate_driver_cleanup();
965         return 0;
966 }
967
968 static int amd_pstate_change_mode_without_dvr_change(int mode)
969 {
970         int cpu = 0;
971
972         cppc_state = mode;
973
974         if (boot_cpu_has(X86_FEATURE_CPPC) || cppc_state == AMD_PSTATE_ACTIVE)
975                 return 0;
976
977         for_each_present_cpu(cpu) {
978                 cppc_set_auto_sel(cpu, (cppc_state == AMD_PSTATE_PASSIVE) ? 0 : 1);
979         }
980
981         return 0;
982 }
983
984 static int amd_pstate_change_driver_mode(int mode)
985 {
986         int ret;
987
988         ret = amd_pstate_unregister_driver(0);
989         if (ret)
990                 return ret;
991
992         ret = amd_pstate_register_driver(mode);
993         if (ret)
994                 return ret;
995
996         return 0;
997 }
998
999 static cppc_mode_transition_fn mode_state_machine[AMD_PSTATE_MAX][AMD_PSTATE_MAX] = {
1000         [AMD_PSTATE_DISABLE]         = {
1001                 [AMD_PSTATE_DISABLE]     = NULL,
1002                 [AMD_PSTATE_PASSIVE]     = amd_pstate_register_driver,
1003                 [AMD_PSTATE_ACTIVE]      = amd_pstate_register_driver,
1004                 [AMD_PSTATE_GUIDED]      = amd_pstate_register_driver,
1005         },
1006         [AMD_PSTATE_PASSIVE]         = {
1007                 [AMD_PSTATE_DISABLE]     = amd_pstate_unregister_driver,
1008                 [AMD_PSTATE_PASSIVE]     = NULL,
1009                 [AMD_PSTATE_ACTIVE]      = amd_pstate_change_driver_mode,
1010                 [AMD_PSTATE_GUIDED]      = amd_pstate_change_mode_without_dvr_change,
1011         },
1012         [AMD_PSTATE_ACTIVE]          = {
1013                 [AMD_PSTATE_DISABLE]     = amd_pstate_unregister_driver,
1014                 [AMD_PSTATE_PASSIVE]     = amd_pstate_change_driver_mode,
1015                 [AMD_PSTATE_ACTIVE]      = NULL,
1016                 [AMD_PSTATE_GUIDED]      = amd_pstate_change_driver_mode,
1017         },
1018         [AMD_PSTATE_GUIDED]          = {
1019                 [AMD_PSTATE_DISABLE]     = amd_pstate_unregister_driver,
1020                 [AMD_PSTATE_PASSIVE]     = amd_pstate_change_mode_without_dvr_change,
1021                 [AMD_PSTATE_ACTIVE]      = amd_pstate_change_driver_mode,
1022                 [AMD_PSTATE_GUIDED]      = NULL,
1023         },
1024 };
1025
1026 static ssize_t amd_pstate_show_status(char *buf)
1027 {
1028         if (!current_pstate_driver)
1029                 return sysfs_emit(buf, "disable\n");
1030
1031         return sysfs_emit(buf, "%s\n", amd_pstate_mode_string[cppc_state]);
1032 }
1033
1034 static int amd_pstate_update_status(const char *buf, size_t size)
1035 {
1036         int mode_idx;
1037
1038         if (size > strlen("passive") || size < strlen("active"))
1039                 return -EINVAL;
1040
1041         mode_idx = get_mode_idx_from_str(buf, size);
1042
1043         if (mode_idx < 0 || mode_idx >= AMD_PSTATE_MAX)
1044                 return -EINVAL;
1045
1046         if (mode_state_machine[cppc_state][mode_idx])
1047                 return mode_state_machine[cppc_state][mode_idx](mode_idx);
1048
1049         return 0;
1050 }
1051
1052 static ssize_t status_show(struct device *dev,
1053                            struct device_attribute *attr, char *buf)
1054 {
1055         ssize_t ret;
1056
1057         mutex_lock(&amd_pstate_driver_lock);
1058         ret = amd_pstate_show_status(buf);
1059         mutex_unlock(&amd_pstate_driver_lock);
1060
1061         return ret;
1062 }
1063
1064 static ssize_t status_store(struct device *a, struct device_attribute *b,
1065                             const char *buf, size_t count)
1066 {
1067         char *p = memchr(buf, '\n', count);
1068         int ret;
1069
1070         mutex_lock(&amd_pstate_driver_lock);
1071         ret = amd_pstate_update_status(buf, p ? p - buf : count);
1072         mutex_unlock(&amd_pstate_driver_lock);
1073
1074         return ret < 0 ? ret : count;
1075 }
1076
1077 cpufreq_freq_attr_ro(amd_pstate_max_freq);
1078 cpufreq_freq_attr_ro(amd_pstate_lowest_nonlinear_freq);
1079
1080 cpufreq_freq_attr_ro(amd_pstate_highest_perf);
1081 cpufreq_freq_attr_rw(energy_performance_preference);
1082 cpufreq_freq_attr_ro(energy_performance_available_preferences);
1083 static DEVICE_ATTR_RW(status);
1084
1085 static struct freq_attr *amd_pstate_attr[] = {
1086         &amd_pstate_max_freq,
1087         &amd_pstate_lowest_nonlinear_freq,
1088         &amd_pstate_highest_perf,
1089         NULL,
1090 };
1091
1092 static struct freq_attr *amd_pstate_epp_attr[] = {
1093         &amd_pstate_max_freq,
1094         &amd_pstate_lowest_nonlinear_freq,
1095         &amd_pstate_highest_perf,
1096         &energy_performance_preference,
1097         &energy_performance_available_preferences,
1098         NULL,
1099 };
1100
1101 static struct attribute *pstate_global_attributes[] = {
1102         &dev_attr_status.attr,
1103         NULL
1104 };
1105
1106 static const struct attribute_group amd_pstate_global_attr_group = {
1107         .name = "amd_pstate",
1108         .attrs = pstate_global_attributes,
1109 };
1110
1111 static bool amd_pstate_acpi_pm_profile_server(void)
1112 {
1113         switch (acpi_gbl_FADT.preferred_profile) {
1114         case PM_ENTERPRISE_SERVER:
1115         case PM_SOHO_SERVER:
1116         case PM_PERFORMANCE_SERVER:
1117                 return true;
1118         }
1119         return false;
1120 }
1121
1122 static bool amd_pstate_acpi_pm_profile_undefined(void)
1123 {
1124         if (acpi_gbl_FADT.preferred_profile == PM_UNSPECIFIED)
1125                 return true;
1126         if (acpi_gbl_FADT.preferred_profile >= NR_PM_PROFILES)
1127                 return true;
1128         return false;
1129 }
1130
1131 static int amd_pstate_epp_cpu_init(struct cpufreq_policy *policy)
1132 {
1133         int min_freq, max_freq, nominal_freq, lowest_nonlinear_freq, ret;
1134         struct amd_cpudata *cpudata;
1135         struct device *dev;
1136         u64 value;
1137
1138         /*
1139          * Resetting PERF_CTL_MSR will put the CPU in P0 frequency,
1140          * which is ideal for initialization process.
1141          */
1142         amd_perf_ctl_reset(policy->cpu);
1143         dev = get_cpu_device(policy->cpu);
1144         if (!dev)
1145                 return -ENODEV;
1146
1147         cpudata = kzalloc(sizeof(*cpudata), GFP_KERNEL);
1148         if (!cpudata)
1149                 return -ENOMEM;
1150
1151         cpudata->cpu = policy->cpu;
1152         cpudata->epp_policy = 0;
1153
1154         ret = amd_pstate_init_perf(cpudata);
1155         if (ret)
1156                 goto free_cpudata1;
1157
1158         min_freq = amd_get_min_freq(cpudata);
1159         max_freq = amd_get_max_freq(cpudata);
1160         nominal_freq = amd_get_nominal_freq(cpudata);
1161         lowest_nonlinear_freq = amd_get_lowest_nonlinear_freq(cpudata);
1162         if (min_freq < 0 || max_freq < 0 || min_freq > max_freq) {
1163                 dev_err(dev, "min_freq(%d) or max_freq(%d) value is incorrect\n",
1164                                 min_freq, max_freq);
1165                 ret = -EINVAL;
1166                 goto free_cpudata1;
1167         }
1168
1169         policy->cpuinfo.min_freq = min_freq;
1170         policy->cpuinfo.max_freq = max_freq;
1171         /* It will be updated by governor */
1172         policy->cur = policy->cpuinfo.min_freq;
1173
1174         /* Initial processor data capability frequencies */
1175         cpudata->max_freq = max_freq;
1176         cpudata->min_freq = min_freq;
1177         cpudata->nominal_freq = nominal_freq;
1178         cpudata->lowest_nonlinear_freq = lowest_nonlinear_freq;
1179
1180         policy->driver_data = cpudata;
1181
1182         cpudata->epp_cached = amd_pstate_get_epp(cpudata, 0);
1183
1184         policy->min = policy->cpuinfo.min_freq;
1185         policy->max = policy->cpuinfo.max_freq;
1186
1187         /*
1188          * Set the policy to provide a valid fallback value in case
1189          * the default cpufreq governor is neither powersave nor performance.
1190          */
1191         if (amd_pstate_acpi_pm_profile_server() ||
1192             amd_pstate_acpi_pm_profile_undefined())
1193                 policy->policy = CPUFREQ_POLICY_PERFORMANCE;
1194         else
1195                 policy->policy = CPUFREQ_POLICY_POWERSAVE;
1196
1197         if (boot_cpu_has(X86_FEATURE_CPPC)) {
1198                 ret = rdmsrl_on_cpu(cpudata->cpu, MSR_AMD_CPPC_REQ, &value);
1199                 if (ret)
1200                         return ret;
1201                 WRITE_ONCE(cpudata->cppc_req_cached, value);
1202
1203                 ret = rdmsrl_on_cpu(cpudata->cpu, MSR_AMD_CPPC_CAP1, &value);
1204                 if (ret)
1205                         return ret;
1206                 WRITE_ONCE(cpudata->cppc_cap1_cached, value);
1207         }
1208         amd_pstate_boost_init(cpudata);
1209
1210         return 0;
1211
1212 free_cpudata1:
1213         kfree(cpudata);
1214         return ret;
1215 }
1216
1217 static int amd_pstate_epp_cpu_exit(struct cpufreq_policy *policy)
1218 {
1219         pr_debug("CPU %d exiting\n", policy->cpu);
1220         return 0;
1221 }
1222
1223 static void amd_pstate_epp_update_limit(struct cpufreq_policy *policy)
1224 {
1225         struct amd_cpudata *cpudata = policy->driver_data;
1226         u32 max_perf, min_perf, min_limit_perf, max_limit_perf;
1227         u64 value;
1228         s16 epp;
1229
1230         max_perf = READ_ONCE(cpudata->highest_perf);
1231         min_perf = READ_ONCE(cpudata->lowest_perf);
1232         max_limit_perf = div_u64(policy->max * cpudata->highest_perf, cpudata->max_freq);
1233         min_limit_perf = div_u64(policy->min * cpudata->highest_perf, cpudata->max_freq);
1234
1235         max_perf = clamp_t(unsigned long, max_perf, cpudata->min_limit_perf,
1236                         cpudata->max_limit_perf);
1237         min_perf = clamp_t(unsigned long, min_perf, cpudata->min_limit_perf,
1238                         cpudata->max_limit_perf);
1239
1240         WRITE_ONCE(cpudata->max_limit_perf, max_limit_perf);
1241         WRITE_ONCE(cpudata->min_limit_perf, min_limit_perf);
1242
1243         value = READ_ONCE(cpudata->cppc_req_cached);
1244
1245         if (cpudata->policy == CPUFREQ_POLICY_PERFORMANCE)
1246                 min_perf = max_perf;
1247
1248         /* Initial min/max values for CPPC Performance Controls Register */
1249         value &= ~AMD_CPPC_MIN_PERF(~0L);
1250         value |= AMD_CPPC_MIN_PERF(min_perf);
1251
1252         value &= ~AMD_CPPC_MAX_PERF(~0L);
1253         value |= AMD_CPPC_MAX_PERF(max_perf);
1254
1255         /* CPPC EPP feature require to set zero to the desire perf bit */
1256         value &= ~AMD_CPPC_DES_PERF(~0L);
1257         value |= AMD_CPPC_DES_PERF(0);
1258
1259         cpudata->epp_policy = cpudata->policy;
1260
1261         /* Get BIOS pre-defined epp value */
1262         epp = amd_pstate_get_epp(cpudata, value);
1263         if (epp < 0) {
1264                 /**
1265                  * This return value can only be negative for shared_memory
1266                  * systems where EPP register read/write not supported.
1267                  */
1268                 return;
1269         }
1270
1271         if (cpudata->policy == CPUFREQ_POLICY_PERFORMANCE)
1272                 epp = 0;
1273
1274         /* Set initial EPP value */
1275         if (boot_cpu_has(X86_FEATURE_CPPC)) {
1276                 value &= ~GENMASK_ULL(31, 24);
1277                 value |= (u64)epp << 24;
1278         }
1279
1280         WRITE_ONCE(cpudata->cppc_req_cached, value);
1281         amd_pstate_set_epp(cpudata, epp);
1282 }
1283
1284 static int amd_pstate_epp_set_policy(struct cpufreq_policy *policy)
1285 {
1286         struct amd_cpudata *cpudata = policy->driver_data;
1287
1288         if (!policy->cpuinfo.max_freq)
1289                 return -ENODEV;
1290
1291         pr_debug("set_policy: cpuinfo.max %u policy->max %u\n",
1292                                 policy->cpuinfo.max_freq, policy->max);
1293
1294         cpudata->policy = policy->policy;
1295
1296         amd_pstate_epp_update_limit(policy);
1297
1298         return 0;
1299 }
1300
1301 static void amd_pstate_epp_reenable(struct amd_cpudata *cpudata)
1302 {
1303         struct cppc_perf_ctrls perf_ctrls;
1304         u64 value, max_perf;
1305         int ret;
1306
1307         ret = amd_pstate_enable(true);
1308         if (ret)
1309                 pr_err("failed to enable amd pstate during resume, return %d\n", ret);
1310
1311         value = READ_ONCE(cpudata->cppc_req_cached);
1312         max_perf = READ_ONCE(cpudata->highest_perf);
1313
1314         if (boot_cpu_has(X86_FEATURE_CPPC)) {
1315                 wrmsrl_on_cpu(cpudata->cpu, MSR_AMD_CPPC_REQ, value);
1316         } else {
1317                 perf_ctrls.max_perf = max_perf;
1318                 perf_ctrls.energy_perf = AMD_CPPC_ENERGY_PERF_PREF(cpudata->epp_cached);
1319                 cppc_set_perf(cpudata->cpu, &perf_ctrls);
1320         }
1321 }
1322
1323 static int amd_pstate_epp_cpu_online(struct cpufreq_policy *policy)
1324 {
1325         struct amd_cpudata *cpudata = policy->driver_data;
1326
1327         pr_debug("AMD CPU Core %d going online\n", cpudata->cpu);
1328
1329         if (cppc_state == AMD_PSTATE_ACTIVE) {
1330                 amd_pstate_epp_reenable(cpudata);
1331                 cpudata->suspended = false;
1332         }
1333
1334         return 0;
1335 }
1336
1337 static void amd_pstate_epp_offline(struct cpufreq_policy *policy)
1338 {
1339         struct amd_cpudata *cpudata = policy->driver_data;
1340         struct cppc_perf_ctrls perf_ctrls;
1341         int min_perf;
1342         u64 value;
1343
1344         min_perf = READ_ONCE(cpudata->lowest_perf);
1345         value = READ_ONCE(cpudata->cppc_req_cached);
1346
1347         mutex_lock(&amd_pstate_limits_lock);
1348         if (boot_cpu_has(X86_FEATURE_CPPC)) {
1349                 cpudata->epp_policy = CPUFREQ_POLICY_UNKNOWN;
1350
1351                 /* Set max perf same as min perf */
1352                 value &= ~AMD_CPPC_MAX_PERF(~0L);
1353                 value |= AMD_CPPC_MAX_PERF(min_perf);
1354                 value &= ~AMD_CPPC_MIN_PERF(~0L);
1355                 value |= AMD_CPPC_MIN_PERF(min_perf);
1356                 wrmsrl_on_cpu(cpudata->cpu, MSR_AMD_CPPC_REQ, value);
1357         } else {
1358                 perf_ctrls.desired_perf = 0;
1359                 perf_ctrls.max_perf = min_perf;
1360                 perf_ctrls.energy_perf = AMD_CPPC_ENERGY_PERF_PREF(HWP_EPP_BALANCE_POWERSAVE);
1361                 cppc_set_perf(cpudata->cpu, &perf_ctrls);
1362         }
1363         mutex_unlock(&amd_pstate_limits_lock);
1364 }
1365
1366 static int amd_pstate_epp_cpu_offline(struct cpufreq_policy *policy)
1367 {
1368         struct amd_cpudata *cpudata = policy->driver_data;
1369
1370         pr_debug("AMD CPU Core %d going offline\n", cpudata->cpu);
1371
1372         if (cpudata->suspended)
1373                 return 0;
1374
1375         if (cppc_state == AMD_PSTATE_ACTIVE)
1376                 amd_pstate_epp_offline(policy);
1377
1378         return 0;
1379 }
1380
1381 static int amd_pstate_epp_verify_policy(struct cpufreq_policy_data *policy)
1382 {
1383         cpufreq_verify_within_cpu_limits(policy);
1384         pr_debug("policy_max =%d, policy_min=%d\n", policy->max, policy->min);
1385         return 0;
1386 }
1387
1388 static int amd_pstate_epp_suspend(struct cpufreq_policy *policy)
1389 {
1390         struct amd_cpudata *cpudata = policy->driver_data;
1391         int ret;
1392
1393         /* avoid suspending when EPP is not enabled */
1394         if (cppc_state != AMD_PSTATE_ACTIVE)
1395                 return 0;
1396
1397         /* set this flag to avoid setting core offline*/
1398         cpudata->suspended = true;
1399
1400         /* disable CPPC in lowlevel firmware */
1401         ret = amd_pstate_enable(false);
1402         if (ret)
1403                 pr_err("failed to suspend, return %d\n", ret);
1404
1405         return 0;
1406 }
1407
1408 static int amd_pstate_epp_resume(struct cpufreq_policy *policy)
1409 {
1410         struct amd_cpudata *cpudata = policy->driver_data;
1411
1412         if (cpudata->suspended) {
1413                 mutex_lock(&amd_pstate_limits_lock);
1414
1415                 /* enable amd pstate from suspend state*/
1416                 amd_pstate_epp_reenable(cpudata);
1417
1418                 mutex_unlock(&amd_pstate_limits_lock);
1419
1420                 cpudata->suspended = false;
1421         }
1422
1423         return 0;
1424 }
1425
1426 static struct cpufreq_driver amd_pstate_driver = {
1427         .flags          = CPUFREQ_CONST_LOOPS | CPUFREQ_NEED_UPDATE_LIMITS,
1428         .verify         = amd_pstate_verify,
1429         .target         = amd_pstate_target,
1430         .fast_switch    = amd_pstate_fast_switch,
1431         .init           = amd_pstate_cpu_init,
1432         .exit           = amd_pstate_cpu_exit,
1433         .suspend        = amd_pstate_cpu_suspend,
1434         .resume         = amd_pstate_cpu_resume,
1435         .set_boost      = amd_pstate_set_boost,
1436         .name           = "amd-pstate",
1437         .attr           = amd_pstate_attr,
1438 };
1439
1440 static struct cpufreq_driver amd_pstate_epp_driver = {
1441         .flags          = CPUFREQ_CONST_LOOPS,
1442         .verify         = amd_pstate_epp_verify_policy,
1443         .setpolicy      = amd_pstate_epp_set_policy,
1444         .init           = amd_pstate_epp_cpu_init,
1445         .exit           = amd_pstate_epp_cpu_exit,
1446         .offline        = amd_pstate_epp_cpu_offline,
1447         .online         = amd_pstate_epp_cpu_online,
1448         .suspend        = amd_pstate_epp_suspend,
1449         .resume         = amd_pstate_epp_resume,
1450         .name           = "amd-pstate-epp",
1451         .attr           = amd_pstate_epp_attr,
1452 };
1453
1454 static int __init amd_pstate_set_driver(int mode_idx)
1455 {
1456         if (mode_idx >= AMD_PSTATE_DISABLE && mode_idx < AMD_PSTATE_MAX) {
1457                 cppc_state = mode_idx;
1458                 if (cppc_state == AMD_PSTATE_DISABLE)
1459                         pr_info("driver is explicitly disabled\n");
1460
1461                 if (cppc_state == AMD_PSTATE_ACTIVE)
1462                         current_pstate_driver = &amd_pstate_epp_driver;
1463
1464                 if (cppc_state == AMD_PSTATE_PASSIVE || cppc_state == AMD_PSTATE_GUIDED)
1465                         current_pstate_driver = &amd_pstate_driver;
1466
1467                 return 0;
1468         }
1469
1470         return -EINVAL;
1471 }
1472
1473 static int __init amd_pstate_init(void)
1474 {
1475         struct device *dev_root;
1476         int ret;
1477
1478         if (boot_cpu_data.x86_vendor != X86_VENDOR_AMD)
1479                 return -ENODEV;
1480
1481         if (!acpi_cpc_valid()) {
1482                 pr_warn_once("the _CPC object is not present in SBIOS or ACPI disabled\n");
1483                 return -ENODEV;
1484         }
1485
1486         /* don't keep reloading if cpufreq_driver exists */
1487         if (cpufreq_get_current_driver())
1488                 return -EEXIST;
1489
1490         switch (cppc_state) {
1491         case AMD_PSTATE_UNDEFINED:
1492                 /* Disable on the following configs by default:
1493                  * 1. Undefined platforms
1494                  * 2. Server platforms
1495                  * 3. Shared memory designs
1496                  */
1497                 if (amd_pstate_acpi_pm_profile_undefined() ||
1498                     amd_pstate_acpi_pm_profile_server() ||
1499                     !boot_cpu_has(X86_FEATURE_CPPC)) {
1500                         pr_info("driver load is disabled, boot with specific mode to enable this\n");
1501                         return -ENODEV;
1502                 }
1503                 ret = amd_pstate_set_driver(CONFIG_X86_AMD_PSTATE_DEFAULT_MODE);
1504                 if (ret)
1505                         return ret;
1506                 break;
1507         case AMD_PSTATE_DISABLE:
1508                 return -ENODEV;
1509         case AMD_PSTATE_PASSIVE:
1510         case AMD_PSTATE_ACTIVE:
1511         case AMD_PSTATE_GUIDED:
1512                 break;
1513         default:
1514                 return -EINVAL;
1515         }
1516
1517         /* capability check */
1518         if (boot_cpu_has(X86_FEATURE_CPPC)) {
1519                 pr_debug("AMD CPPC MSR based functionality is supported\n");
1520                 if (cppc_state != AMD_PSTATE_ACTIVE)
1521                         current_pstate_driver->adjust_perf = amd_pstate_adjust_perf;
1522         } else {
1523                 pr_debug("AMD CPPC shared memory based functionality is supported\n");
1524                 static_call_update(amd_pstate_enable, cppc_enable);
1525                 static_call_update(amd_pstate_init_perf, cppc_init_perf);
1526                 static_call_update(amd_pstate_update_perf, cppc_update_perf);
1527         }
1528
1529         /* enable amd pstate feature */
1530         ret = amd_pstate_enable(true);
1531         if (ret) {
1532                 pr_err("failed to enable with return %d\n", ret);
1533                 return ret;
1534         }
1535
1536         ret = cpufreq_register_driver(current_pstate_driver);
1537         if (ret)
1538                 pr_err("failed to register with return %d\n", ret);
1539
1540         dev_root = bus_get_dev_root(&cpu_subsys);
1541         if (dev_root) {
1542                 ret = sysfs_create_group(&dev_root->kobj, &amd_pstate_global_attr_group);
1543                 put_device(dev_root);
1544                 if (ret) {
1545                         pr_err("sysfs attribute export failed with error %d.\n", ret);
1546                         goto global_attr_free;
1547                 }
1548         }
1549
1550         return ret;
1551
1552 global_attr_free:
1553         cpufreq_unregister_driver(current_pstate_driver);
1554         return ret;
1555 }
1556 device_initcall(amd_pstate_init);
1557
1558 static int __init amd_pstate_param(char *str)
1559 {
1560         size_t size;
1561         int mode_idx;
1562
1563         if (!str)
1564                 return -EINVAL;
1565
1566         size = strlen(str);
1567         mode_idx = get_mode_idx_from_str(str, size);
1568
1569         return amd_pstate_set_driver(mode_idx);
1570 }
1571 early_param("amd_pstate", amd_pstate_param);
1572
1573 MODULE_AUTHOR("Huang Rui <ray.huang@amd.com>");
1574 MODULE_DESCRIPTION("AMD Processor P-state Frequency Driver");