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1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * CPPC (Collaborative Processor Performance Control) driver for
4  * interfacing with the CPUfreq layer and governors. See
5  * cppc_acpi.c for CPPC specific methods.
6  *
7  * (C) Copyright 2014, 2015 Linaro Ltd.
8  * Author: Ashwin Chaugule <[email protected]>
9  */
10
11 #define pr_fmt(fmt)     "CPPC Cpufreq:" fmt
12
13 #include <linux/arch_topology.h>
14 #include <linux/kernel.h>
15 #include <linux/module.h>
16 #include <linux/delay.h>
17 #include <linux/cpu.h>
18 #include <linux/cpufreq.h>
19 #include <linux/irq_work.h>
20 #include <linux/kthread.h>
21 #include <linux/time.h>
22 #include <linux/vmalloc.h>
23 #include <uapi/linux/sched/types.h>
24
25 #include <asm/unaligned.h>
26
27 #include <acpi/cppc_acpi.h>
28
29 /*
30  * This list contains information parsed from per CPU ACPI _CPC and _PSD
31  * structures: e.g. the highest and lowest supported performance, capabilities,
32  * desired performance, level requested etc. Depending on the share_type, not
33  * all CPUs will have an entry in the list.
34  */
35 static LIST_HEAD(cpu_data_list);
36
37 static bool boost_supported;
38
39 struct cppc_workaround_oem_info {
40         char oem_id[ACPI_OEM_ID_SIZE + 1];
41         char oem_table_id[ACPI_OEM_TABLE_ID_SIZE + 1];
42         u32 oem_revision;
43 };
44
45 static struct cppc_workaround_oem_info wa_info[] = {
46         {
47                 .oem_id         = "HISI  ",
48                 .oem_table_id   = "HIP07   ",
49                 .oem_revision   = 0,
50         }, {
51                 .oem_id         = "HISI  ",
52                 .oem_table_id   = "HIP08   ",
53                 .oem_revision   = 0,
54         }
55 };
56
57 static struct cpufreq_driver cppc_cpufreq_driver;
58
59 static enum {
60         FIE_UNSET = -1,
61         FIE_ENABLED,
62         FIE_DISABLED
63 } fie_disabled = FIE_UNSET;
64
65 #ifdef CONFIG_ACPI_CPPC_CPUFREQ_FIE
66 module_param(fie_disabled, int, 0444);
67 MODULE_PARM_DESC(fie_disabled, "Disable Frequency Invariance Engine (FIE)");
68
69 /* Frequency invariance support */
70 struct cppc_freq_invariance {
71         int cpu;
72         struct irq_work irq_work;
73         struct kthread_work work;
74         struct cppc_perf_fb_ctrs prev_perf_fb_ctrs;
75         struct cppc_cpudata *cpu_data;
76 };
77
78 static DEFINE_PER_CPU(struct cppc_freq_invariance, cppc_freq_inv);
79 static struct kthread_worker *kworker_fie;
80
81 static unsigned int hisi_cppc_cpufreq_get_rate(unsigned int cpu);
82 static int cppc_perf_from_fbctrs(struct cppc_cpudata *cpu_data,
83                                  struct cppc_perf_fb_ctrs *fb_ctrs_t0,
84                                  struct cppc_perf_fb_ctrs *fb_ctrs_t1);
85
86 /**
87  * cppc_scale_freq_workfn - CPPC arch_freq_scale updater for frequency invariance
88  * @work: The work item.
89  *
90  * The CPPC driver register itself with the topology core to provide its own
91  * implementation (cppc_scale_freq_tick()) of topology_scale_freq_tick() which
92  * gets called by the scheduler on every tick.
93  *
94  * Note that the arch specific counters have higher priority than CPPC counters,
95  * if available, though the CPPC driver doesn't need to have any special
96  * handling for that.
97  *
98  * On an invocation of cppc_scale_freq_tick(), we schedule an irq work (since we
99  * reach here from hard-irq context), which then schedules a normal work item
100  * and cppc_scale_freq_workfn() updates the per_cpu arch_freq_scale variable
101  * based on the counter updates since the last tick.
102  */
103 static void cppc_scale_freq_workfn(struct kthread_work *work)
104 {
105         struct cppc_freq_invariance *cppc_fi;
106         struct cppc_perf_fb_ctrs fb_ctrs = {0};
107         struct cppc_cpudata *cpu_data;
108         unsigned long local_freq_scale;
109         u64 perf;
110
111         cppc_fi = container_of(work, struct cppc_freq_invariance, work);
112         cpu_data = cppc_fi->cpu_data;
113
114         if (cppc_get_perf_ctrs(cppc_fi->cpu, &fb_ctrs)) {
115                 pr_warn("%s: failed to read perf counters\n", __func__);
116                 return;
117         }
118
119         perf = cppc_perf_from_fbctrs(cpu_data, &cppc_fi->prev_perf_fb_ctrs,
120                                      &fb_ctrs);
121         cppc_fi->prev_perf_fb_ctrs = fb_ctrs;
122
123         perf <<= SCHED_CAPACITY_SHIFT;
124         local_freq_scale = div64_u64(perf, cpu_data->perf_caps.highest_perf);
125
126         /* This can happen due to counter's overflow */
127         if (unlikely(local_freq_scale > 1024))
128                 local_freq_scale = 1024;
129
130         per_cpu(arch_freq_scale, cppc_fi->cpu) = local_freq_scale;
131 }
132
133 static void cppc_irq_work(struct irq_work *irq_work)
134 {
135         struct cppc_freq_invariance *cppc_fi;
136
137         cppc_fi = container_of(irq_work, struct cppc_freq_invariance, irq_work);
138         kthread_queue_work(kworker_fie, &cppc_fi->work);
139 }
140
141 static void cppc_scale_freq_tick(void)
142 {
143         struct cppc_freq_invariance *cppc_fi = &per_cpu(cppc_freq_inv, smp_processor_id());
144
145         /*
146          * cppc_get_perf_ctrs() can potentially sleep, call that from the right
147          * context.
148          */
149         irq_work_queue(&cppc_fi->irq_work);
150 }
151
152 static struct scale_freq_data cppc_sftd = {
153         .source = SCALE_FREQ_SOURCE_CPPC,
154         .set_freq_scale = cppc_scale_freq_tick,
155 };
156
157 static void cppc_cpufreq_cpu_fie_init(struct cpufreq_policy *policy)
158 {
159         struct cppc_freq_invariance *cppc_fi;
160         int cpu, ret;
161
162         if (fie_disabled)
163                 return;
164
165         for_each_cpu(cpu, policy->cpus) {
166                 cppc_fi = &per_cpu(cppc_freq_inv, cpu);
167                 cppc_fi->cpu = cpu;
168                 cppc_fi->cpu_data = policy->driver_data;
169                 kthread_init_work(&cppc_fi->work, cppc_scale_freq_workfn);
170                 init_irq_work(&cppc_fi->irq_work, cppc_irq_work);
171
172                 ret = cppc_get_perf_ctrs(cpu, &cppc_fi->prev_perf_fb_ctrs);
173                 if (ret) {
174                         pr_warn("%s: failed to read perf counters for cpu:%d: %d\n",
175                                 __func__, cpu, ret);
176
177                         /*
178                          * Don't abort if the CPU was offline while the driver
179                          * was getting registered.
180                          */
181                         if (cpu_online(cpu))
182                                 return;
183                 }
184         }
185
186         /* Register for freq-invariance */
187         topology_set_scale_freq_source(&cppc_sftd, policy->cpus);
188 }
189
190 /*
191  * We free all the resources on policy's removal and not on CPU removal as the
192  * irq-work are per-cpu and the hotplug core takes care of flushing the pending
193  * irq-works (hint: smpcfd_dying_cpu()) on CPU hotplug. Even if the kthread-work
194  * fires on another CPU after the concerned CPU is removed, it won't harm.
195  *
196  * We just need to make sure to remove them all on policy->exit().
197  */
198 static void cppc_cpufreq_cpu_fie_exit(struct cpufreq_policy *policy)
199 {
200         struct cppc_freq_invariance *cppc_fi;
201         int cpu;
202
203         if (fie_disabled)
204                 return;
205
206         /* policy->cpus will be empty here, use related_cpus instead */
207         topology_clear_scale_freq_source(SCALE_FREQ_SOURCE_CPPC, policy->related_cpus);
208
209         for_each_cpu(cpu, policy->related_cpus) {
210                 cppc_fi = &per_cpu(cppc_freq_inv, cpu);
211                 irq_work_sync(&cppc_fi->irq_work);
212                 kthread_cancel_work_sync(&cppc_fi->work);
213         }
214 }
215
216 static void __init cppc_freq_invariance_init(void)
217 {
218         struct sched_attr attr = {
219                 .size           = sizeof(struct sched_attr),
220                 .sched_policy   = SCHED_DEADLINE,
221                 .sched_nice     = 0,
222                 .sched_priority = 0,
223                 /*
224                  * Fake (unused) bandwidth; workaround to "fix"
225                  * priority inheritance.
226                  */
227                 .sched_runtime  = 1000000,
228                 .sched_deadline = 10000000,
229                 .sched_period   = 10000000,
230         };
231         int ret;
232
233         if (fie_disabled != FIE_ENABLED && fie_disabled != FIE_DISABLED) {
234                 fie_disabled = FIE_ENABLED;
235                 if (cppc_perf_ctrs_in_pcc()) {
236                         pr_info("FIE not enabled on systems with registers in PCC\n");
237                         fie_disabled = FIE_DISABLED;
238                 }
239         }
240
241         if (fie_disabled)
242                 return;
243
244         kworker_fie = kthread_create_worker(0, "cppc_fie");
245         if (IS_ERR(kworker_fie)) {
246                 pr_warn("%s: failed to create kworker_fie: %ld\n", __func__,
247                         PTR_ERR(kworker_fie));
248                 fie_disabled = FIE_DISABLED;
249                 return;
250         }
251
252         ret = sched_setattr_nocheck(kworker_fie->task, &attr);
253         if (ret) {
254                 pr_warn("%s: failed to set SCHED_DEADLINE: %d\n", __func__,
255                         ret);
256                 kthread_destroy_worker(kworker_fie);
257                 fie_disabled = FIE_DISABLED;
258         }
259 }
260
261 static void cppc_freq_invariance_exit(void)
262 {
263         if (fie_disabled)
264                 return;
265
266         kthread_destroy_worker(kworker_fie);
267 }
268
269 #else
270 static inline void cppc_cpufreq_cpu_fie_init(struct cpufreq_policy *policy)
271 {
272 }
273
274 static inline void cppc_cpufreq_cpu_fie_exit(struct cpufreq_policy *policy)
275 {
276 }
277
278 static inline void cppc_freq_invariance_init(void)
279 {
280 }
281
282 static inline void cppc_freq_invariance_exit(void)
283 {
284 }
285 #endif /* CONFIG_ACPI_CPPC_CPUFREQ_FIE */
286
287 static int cppc_cpufreq_set_target(struct cpufreq_policy *policy,
288                                    unsigned int target_freq,
289                                    unsigned int relation)
290 {
291         struct cppc_cpudata *cpu_data = policy->driver_data;
292         unsigned int cpu = policy->cpu;
293         struct cpufreq_freqs freqs;
294         int ret = 0;
295
296         cpu_data->perf_ctrls.desired_perf =
297                         cppc_khz_to_perf(&cpu_data->perf_caps, target_freq);
298         freqs.old = policy->cur;
299         freqs.new = target_freq;
300
301         cpufreq_freq_transition_begin(policy, &freqs);
302         ret = cppc_set_perf(cpu, &cpu_data->perf_ctrls);
303         cpufreq_freq_transition_end(policy, &freqs, ret != 0);
304
305         if (ret)
306                 pr_debug("Failed to set target on CPU:%d. ret:%d\n",
307                          cpu, ret);
308
309         return ret;
310 }
311
312 static unsigned int cppc_cpufreq_fast_switch(struct cpufreq_policy *policy,
313                                               unsigned int target_freq)
314 {
315         struct cppc_cpudata *cpu_data = policy->driver_data;
316         unsigned int cpu = policy->cpu;
317         u32 desired_perf;
318         int ret;
319
320         desired_perf = cppc_khz_to_perf(&cpu_data->perf_caps, target_freq);
321         cpu_data->perf_ctrls.desired_perf = desired_perf;
322         ret = cppc_set_perf(cpu, &cpu_data->perf_ctrls);
323
324         if (ret) {
325                 pr_debug("Failed to set target on CPU:%d. ret:%d\n",
326                          cpu, ret);
327                 return 0;
328         }
329
330         return target_freq;
331 }
332
333 static int cppc_verify_policy(struct cpufreq_policy_data *policy)
334 {
335         cpufreq_verify_within_cpu_limits(policy);
336         return 0;
337 }
338
339 /*
340  * The PCC subspace describes the rate at which platform can accept commands
341  * on the shared PCC channel (including READs which do not count towards freq
342  * transition requests), so ideally we need to use the PCC values as a fallback
343  * if we don't have a platform specific transition_delay_us
344  */
345 #ifdef CONFIG_ARM64
346 #include <asm/cputype.h>
347
348 static unsigned int cppc_cpufreq_get_transition_delay_us(unsigned int cpu)
349 {
350         unsigned long implementor = read_cpuid_implementor();
351         unsigned long part_num = read_cpuid_part_number();
352
353         switch (implementor) {
354         case ARM_CPU_IMP_QCOM:
355                 switch (part_num) {
356                 case QCOM_CPU_PART_FALKOR_V1:
357                 case QCOM_CPU_PART_FALKOR:
358                         return 10000;
359                 }
360         }
361         return cppc_get_transition_latency(cpu) / NSEC_PER_USEC;
362 }
363 #else
364 static unsigned int cppc_cpufreq_get_transition_delay_us(unsigned int cpu)
365 {
366         return cppc_get_transition_latency(cpu) / NSEC_PER_USEC;
367 }
368 #endif
369
370 #if defined(CONFIG_ARM64) && defined(CONFIG_ENERGY_MODEL)
371
372 static DEFINE_PER_CPU(unsigned int, efficiency_class);
373 static void cppc_cpufreq_register_em(struct cpufreq_policy *policy);
374
375 /* Create an artificial performance state every CPPC_EM_CAP_STEP capacity unit. */
376 #define CPPC_EM_CAP_STEP        (20)
377 /* Increase the cost value by CPPC_EM_COST_STEP every performance state. */
378 #define CPPC_EM_COST_STEP       (1)
379 /* Add a cost gap correspnding to the energy of 4 CPUs. */
380 #define CPPC_EM_COST_GAP        (4 * SCHED_CAPACITY_SCALE * CPPC_EM_COST_STEP \
381                                 / CPPC_EM_CAP_STEP)
382
383 static unsigned int get_perf_level_count(struct cpufreq_policy *policy)
384 {
385         struct cppc_perf_caps *perf_caps;
386         unsigned int min_cap, max_cap;
387         struct cppc_cpudata *cpu_data;
388         int cpu = policy->cpu;
389
390         cpu_data = policy->driver_data;
391         perf_caps = &cpu_data->perf_caps;
392         max_cap = arch_scale_cpu_capacity(cpu);
393         min_cap = div_u64((u64)max_cap * perf_caps->lowest_perf,
394                           perf_caps->highest_perf);
395         if ((min_cap == 0) || (max_cap < min_cap))
396                 return 0;
397         return 1 + max_cap / CPPC_EM_CAP_STEP - min_cap / CPPC_EM_CAP_STEP;
398 }
399
400 /*
401  * The cost is defined as:
402  *   cost = power * max_frequency / frequency
403  */
404 static inline unsigned long compute_cost(int cpu, int step)
405 {
406         return CPPC_EM_COST_GAP * per_cpu(efficiency_class, cpu) +
407                         step * CPPC_EM_COST_STEP;
408 }
409
410 static int cppc_get_cpu_power(struct device *cpu_dev,
411                 unsigned long *power, unsigned long *KHz)
412 {
413         unsigned long perf_step, perf_prev, perf, perf_check;
414         unsigned int min_step, max_step, step, step_check;
415         unsigned long prev_freq = *KHz;
416         unsigned int min_cap, max_cap;
417         struct cpufreq_policy *policy;
418
419         struct cppc_perf_caps *perf_caps;
420         struct cppc_cpudata *cpu_data;
421
422         policy = cpufreq_cpu_get_raw(cpu_dev->id);
423         cpu_data = policy->driver_data;
424         perf_caps = &cpu_data->perf_caps;
425         max_cap = arch_scale_cpu_capacity(cpu_dev->id);
426         min_cap = div_u64((u64)max_cap * perf_caps->lowest_perf,
427                           perf_caps->highest_perf);
428         perf_step = div_u64((u64)CPPC_EM_CAP_STEP * perf_caps->highest_perf,
429                             max_cap);
430         min_step = min_cap / CPPC_EM_CAP_STEP;
431         max_step = max_cap / CPPC_EM_CAP_STEP;
432
433         perf_prev = cppc_khz_to_perf(perf_caps, *KHz);
434         step = perf_prev / perf_step;
435
436         if (step > max_step)
437                 return -EINVAL;
438
439         if (min_step == max_step) {
440                 step = max_step;
441                 perf = perf_caps->highest_perf;
442         } else if (step < min_step) {
443                 step = min_step;
444                 perf = perf_caps->lowest_perf;
445         } else {
446                 step++;
447                 if (step == max_step)
448                         perf = perf_caps->highest_perf;
449                 else
450                         perf = step * perf_step;
451         }
452
453         *KHz = cppc_perf_to_khz(perf_caps, perf);
454         perf_check = cppc_khz_to_perf(perf_caps, *KHz);
455         step_check = perf_check / perf_step;
456
457         /*
458          * To avoid bad integer approximation, check that new frequency value
459          * increased and that the new frequency will be converted to the
460          * desired step value.
461          */
462         while ((*KHz == prev_freq) || (step_check != step)) {
463                 perf++;
464                 *KHz = cppc_perf_to_khz(perf_caps, perf);
465                 perf_check = cppc_khz_to_perf(perf_caps, *KHz);
466                 step_check = perf_check / perf_step;
467         }
468
469         /*
470          * With an artificial EM, only the cost value is used. Still the power
471          * is populated such as 0 < power < EM_MAX_POWER. This allows to add
472          * more sense to the artificial performance states.
473          */
474         *power = compute_cost(cpu_dev->id, step);
475
476         return 0;
477 }
478
479 static int cppc_get_cpu_cost(struct device *cpu_dev, unsigned long KHz,
480                 unsigned long *cost)
481 {
482         unsigned long perf_step, perf_prev;
483         struct cppc_perf_caps *perf_caps;
484         struct cpufreq_policy *policy;
485         struct cppc_cpudata *cpu_data;
486         unsigned int max_cap;
487         int step;
488
489         policy = cpufreq_cpu_get_raw(cpu_dev->id);
490         cpu_data = policy->driver_data;
491         perf_caps = &cpu_data->perf_caps;
492         max_cap = arch_scale_cpu_capacity(cpu_dev->id);
493
494         perf_prev = cppc_khz_to_perf(perf_caps, KHz);
495         perf_step = CPPC_EM_CAP_STEP * perf_caps->highest_perf / max_cap;
496         step = perf_prev / perf_step;
497
498         *cost = compute_cost(cpu_dev->id, step);
499
500         return 0;
501 }
502
503 static int populate_efficiency_class(void)
504 {
505         struct acpi_madt_generic_interrupt *gicc;
506         DECLARE_BITMAP(used_classes, 256) = {};
507         int class, cpu, index;
508
509         for_each_possible_cpu(cpu) {
510                 gicc = acpi_cpu_get_madt_gicc(cpu);
511                 class = gicc->efficiency_class;
512                 bitmap_set(used_classes, class, 1);
513         }
514
515         if (bitmap_weight(used_classes, 256) <= 1) {
516                 pr_debug("Efficiency classes are all equal (=%d). "
517                         "No EM registered", class);
518                 return -EINVAL;
519         }
520
521         /*
522          * Squeeze efficiency class values on [0:#efficiency_class-1].
523          * Values are per spec in [0:255].
524          */
525         index = 0;
526         for_each_set_bit(class, used_classes, 256) {
527                 for_each_possible_cpu(cpu) {
528                         gicc = acpi_cpu_get_madt_gicc(cpu);
529                         if (gicc->efficiency_class == class)
530                                 per_cpu(efficiency_class, cpu) = index;
531                 }
532                 index++;
533         }
534         cppc_cpufreq_driver.register_em = cppc_cpufreq_register_em;
535
536         return 0;
537 }
538
539 static void cppc_cpufreq_register_em(struct cpufreq_policy *policy)
540 {
541         struct cppc_cpudata *cpu_data;
542         struct em_data_callback em_cb =
543                 EM_ADV_DATA_CB(cppc_get_cpu_power, cppc_get_cpu_cost);
544
545         cpu_data = policy->driver_data;
546         em_dev_register_perf_domain(get_cpu_device(policy->cpu),
547                         get_perf_level_count(policy), &em_cb,
548                         cpu_data->shared_cpu_map, 0);
549 }
550
551 #else
552 static int populate_efficiency_class(void)
553 {
554         return 0;
555 }
556 #endif
557
558 static struct cppc_cpudata *cppc_cpufreq_get_cpu_data(unsigned int cpu)
559 {
560         struct cppc_cpudata *cpu_data;
561         int ret;
562
563         cpu_data = kzalloc(sizeof(struct cppc_cpudata), GFP_KERNEL);
564         if (!cpu_data)
565                 goto out;
566
567         if (!zalloc_cpumask_var(&cpu_data->shared_cpu_map, GFP_KERNEL))
568                 goto free_cpu;
569
570         ret = acpi_get_psd_map(cpu, cpu_data);
571         if (ret) {
572                 pr_debug("Err parsing CPU%d PSD data: ret:%d\n", cpu, ret);
573                 goto free_mask;
574         }
575
576         ret = cppc_get_perf_caps(cpu, &cpu_data->perf_caps);
577         if (ret) {
578                 pr_debug("Err reading CPU%d perf caps: ret:%d\n", cpu, ret);
579                 goto free_mask;
580         }
581
582         list_add(&cpu_data->node, &cpu_data_list);
583
584         return cpu_data;
585
586 free_mask:
587         free_cpumask_var(cpu_data->shared_cpu_map);
588 free_cpu:
589         kfree(cpu_data);
590 out:
591         return NULL;
592 }
593
594 static void cppc_cpufreq_put_cpu_data(struct cpufreq_policy *policy)
595 {
596         struct cppc_cpudata *cpu_data = policy->driver_data;
597
598         list_del(&cpu_data->node);
599         free_cpumask_var(cpu_data->shared_cpu_map);
600         kfree(cpu_data);
601         policy->driver_data = NULL;
602 }
603
604 static int cppc_cpufreq_cpu_init(struct cpufreq_policy *policy)
605 {
606         unsigned int cpu = policy->cpu;
607         struct cppc_cpudata *cpu_data;
608         struct cppc_perf_caps *caps;
609         int ret;
610
611         cpu_data = cppc_cpufreq_get_cpu_data(cpu);
612         if (!cpu_data) {
613                 pr_err("Error in acquiring _CPC/_PSD data for CPU%d.\n", cpu);
614                 return -ENODEV;
615         }
616         caps = &cpu_data->perf_caps;
617         policy->driver_data = cpu_data;
618
619         /*
620          * Set min to lowest nonlinear perf to avoid any efficiency penalty (see
621          * Section 8.4.7.1.1.5 of ACPI 6.1 spec)
622          */
623         policy->min = cppc_perf_to_khz(caps, caps->lowest_nonlinear_perf);
624         policy->max = cppc_perf_to_khz(caps, caps->nominal_perf);
625
626         /*
627          * Set cpuinfo.min_freq to Lowest to make the full range of performance
628          * available if userspace wants to use any perf between lowest & lowest
629          * nonlinear perf
630          */
631         policy->cpuinfo.min_freq = cppc_perf_to_khz(caps, caps->lowest_perf);
632         policy->cpuinfo.max_freq = cppc_perf_to_khz(caps, caps->nominal_perf);
633
634         policy->transition_delay_us = cppc_cpufreq_get_transition_delay_us(cpu);
635         policy->shared_type = cpu_data->shared_type;
636
637         switch (policy->shared_type) {
638         case CPUFREQ_SHARED_TYPE_HW:
639         case CPUFREQ_SHARED_TYPE_NONE:
640                 /* Nothing to be done - we'll have a policy for each CPU */
641                 break;
642         case CPUFREQ_SHARED_TYPE_ANY:
643                 /*
644                  * All CPUs in the domain will share a policy and all cpufreq
645                  * operations will use a single cppc_cpudata structure stored
646                  * in policy->driver_data.
647                  */
648                 cpumask_copy(policy->cpus, cpu_data->shared_cpu_map);
649                 break;
650         default:
651                 pr_debug("Unsupported CPU co-ord type: %d\n",
652                          policy->shared_type);
653                 ret = -EFAULT;
654                 goto out;
655         }
656
657         policy->fast_switch_possible = cppc_allow_fast_switch();
658         policy->dvfs_possible_from_any_cpu = true;
659
660         /*
661          * If 'highest_perf' is greater than 'nominal_perf', we assume CPU Boost
662          * is supported.
663          */
664         if (caps->highest_perf > caps->nominal_perf)
665                 boost_supported = true;
666
667         /* Set policy->cur to max now. The governors will adjust later. */
668         policy->cur = cppc_perf_to_khz(caps, caps->highest_perf);
669         cpu_data->perf_ctrls.desired_perf =  caps->highest_perf;
670
671         ret = cppc_set_perf(cpu, &cpu_data->perf_ctrls);
672         if (ret) {
673                 pr_debug("Err setting perf value:%d on CPU:%d. ret:%d\n",
674                          caps->highest_perf, cpu, ret);
675                 goto out;
676         }
677
678         cppc_cpufreq_cpu_fie_init(policy);
679         return 0;
680
681 out:
682         cppc_cpufreq_put_cpu_data(policy);
683         return ret;
684 }
685
686 static void cppc_cpufreq_cpu_exit(struct cpufreq_policy *policy)
687 {
688         struct cppc_cpudata *cpu_data = policy->driver_data;
689         struct cppc_perf_caps *caps = &cpu_data->perf_caps;
690         unsigned int cpu = policy->cpu;
691         int ret;
692
693         cppc_cpufreq_cpu_fie_exit(policy);
694
695         cpu_data->perf_ctrls.desired_perf = caps->lowest_perf;
696
697         ret = cppc_set_perf(cpu, &cpu_data->perf_ctrls);
698         if (ret)
699                 pr_debug("Err setting perf value:%d on CPU:%d. ret:%d\n",
700                          caps->lowest_perf, cpu, ret);
701
702         cppc_cpufreq_put_cpu_data(policy);
703 }
704
705 static inline u64 get_delta(u64 t1, u64 t0)
706 {
707         if (t1 > t0 || t0 > ~(u32)0)
708                 return t1 - t0;
709
710         return (u32)t1 - (u32)t0;
711 }
712
713 static int cppc_perf_from_fbctrs(struct cppc_cpudata *cpu_data,
714                                  struct cppc_perf_fb_ctrs *fb_ctrs_t0,
715                                  struct cppc_perf_fb_ctrs *fb_ctrs_t1)
716 {
717         u64 delta_reference, delta_delivered;
718         u64 reference_perf;
719
720         reference_perf = fb_ctrs_t0->reference_perf;
721
722         delta_reference = get_delta(fb_ctrs_t1->reference,
723                                     fb_ctrs_t0->reference);
724         delta_delivered = get_delta(fb_ctrs_t1->delivered,
725                                     fb_ctrs_t0->delivered);
726
727         /* Check to avoid divide-by zero and invalid delivered_perf */
728         if (!delta_reference || !delta_delivered)
729                 return cpu_data->perf_ctrls.desired_perf;
730
731         return (reference_perf * delta_delivered) / delta_reference;
732 }
733
734 static unsigned int cppc_cpufreq_get_rate(unsigned int cpu)
735 {
736         struct cppc_perf_fb_ctrs fb_ctrs_t0 = {0}, fb_ctrs_t1 = {0};
737         struct cpufreq_policy *policy = cpufreq_cpu_get(cpu);
738         struct cppc_cpudata *cpu_data;
739         u64 delivered_perf;
740         int ret;
741
742         if (!policy)
743                 return -ENODEV;
744
745         cpu_data = policy->driver_data;
746
747         cpufreq_cpu_put(policy);
748
749         ret = cppc_get_perf_ctrs(cpu, &fb_ctrs_t0);
750         if (ret)
751                 return 0;
752
753         udelay(2); /* 2usec delay between sampling */
754
755         ret = cppc_get_perf_ctrs(cpu, &fb_ctrs_t1);
756         if (ret)
757                 return 0;
758
759         delivered_perf = cppc_perf_from_fbctrs(cpu_data, &fb_ctrs_t0,
760                                                &fb_ctrs_t1);
761
762         return cppc_perf_to_khz(&cpu_data->perf_caps, delivered_perf);
763 }
764
765 static int cppc_cpufreq_set_boost(struct cpufreq_policy *policy, int state)
766 {
767         struct cppc_cpudata *cpu_data = policy->driver_data;
768         struct cppc_perf_caps *caps = &cpu_data->perf_caps;
769         int ret;
770
771         if (!boost_supported) {
772                 pr_err("BOOST not supported by CPU or firmware\n");
773                 return -EINVAL;
774         }
775
776         if (state)
777                 policy->max = cppc_perf_to_khz(caps, caps->highest_perf);
778         else
779                 policy->max = cppc_perf_to_khz(caps, caps->nominal_perf);
780         policy->cpuinfo.max_freq = policy->max;
781
782         ret = freq_qos_update_request(policy->max_freq_req, policy->max);
783         if (ret < 0)
784                 return ret;
785
786         return 0;
787 }
788
789 static ssize_t show_freqdomain_cpus(struct cpufreq_policy *policy, char *buf)
790 {
791         struct cppc_cpudata *cpu_data = policy->driver_data;
792
793         return cpufreq_show_cpus(cpu_data->shared_cpu_map, buf);
794 }
795 cpufreq_freq_attr_ro(freqdomain_cpus);
796
797 static struct freq_attr *cppc_cpufreq_attr[] = {
798         &freqdomain_cpus,
799         NULL,
800 };
801
802 static struct cpufreq_driver cppc_cpufreq_driver = {
803         .flags = CPUFREQ_CONST_LOOPS,
804         .verify = cppc_verify_policy,
805         .target = cppc_cpufreq_set_target,
806         .get = cppc_cpufreq_get_rate,
807         .fast_switch = cppc_cpufreq_fast_switch,
808         .init = cppc_cpufreq_cpu_init,
809         .exit = cppc_cpufreq_cpu_exit,
810         .set_boost = cppc_cpufreq_set_boost,
811         .attr = cppc_cpufreq_attr,
812         .name = "cppc_cpufreq",
813 };
814
815 /*
816  * HISI platform does not support delivered performance counter and
817  * reference performance counter. It can calculate the performance using the
818  * platform specific mechanism. We reuse the desired performance register to
819  * store the real performance calculated by the platform.
820  */
821 static unsigned int hisi_cppc_cpufreq_get_rate(unsigned int cpu)
822 {
823         struct cpufreq_policy *policy = cpufreq_cpu_get(cpu);
824         struct cppc_cpudata *cpu_data;
825         u64 desired_perf;
826         int ret;
827
828         if (!policy)
829                 return -ENODEV;
830
831         cpu_data = policy->driver_data;
832
833         cpufreq_cpu_put(policy);
834
835         ret = cppc_get_desired_perf(cpu, &desired_perf);
836         if (ret < 0)
837                 return -EIO;
838
839         return cppc_perf_to_khz(&cpu_data->perf_caps, desired_perf);
840 }
841
842 static void cppc_check_hisi_workaround(void)
843 {
844         struct acpi_table_header *tbl;
845         acpi_status status = AE_OK;
846         int i;
847
848         status = acpi_get_table(ACPI_SIG_PCCT, 0, &tbl);
849         if (ACPI_FAILURE(status) || !tbl)
850                 return;
851
852         for (i = 0; i < ARRAY_SIZE(wa_info); i++) {
853                 if (!memcmp(wa_info[i].oem_id, tbl->oem_id, ACPI_OEM_ID_SIZE) &&
854                     !memcmp(wa_info[i].oem_table_id, tbl->oem_table_id, ACPI_OEM_TABLE_ID_SIZE) &&
855                     wa_info[i].oem_revision == tbl->oem_revision) {
856                         /* Overwrite the get() callback */
857                         cppc_cpufreq_driver.get = hisi_cppc_cpufreq_get_rate;
858                         fie_disabled = FIE_DISABLED;
859                         break;
860                 }
861         }
862
863         acpi_put_table(tbl);
864 }
865
866 static int __init cppc_cpufreq_init(void)
867 {
868         int ret;
869
870         if (!acpi_cpc_valid())
871                 return -ENODEV;
872
873         cppc_check_hisi_workaround();
874         cppc_freq_invariance_init();
875         populate_efficiency_class();
876
877         ret = cpufreq_register_driver(&cppc_cpufreq_driver);
878         if (ret)
879                 cppc_freq_invariance_exit();
880
881         return ret;
882 }
883
884 static inline void free_cpu_data(void)
885 {
886         struct cppc_cpudata *iter, *tmp;
887
888         list_for_each_entry_safe(iter, tmp, &cpu_data_list, node) {
889                 free_cpumask_var(iter->shared_cpu_map);
890                 list_del(&iter->node);
891                 kfree(iter);
892         }
893
894 }
895
896 static void __exit cppc_cpufreq_exit(void)
897 {
898         cpufreq_unregister_driver(&cppc_cpufreq_driver);
899         cppc_freq_invariance_exit();
900
901         free_cpu_data();
902 }
903
904 module_exit(cppc_cpufreq_exit);
905 MODULE_AUTHOR("Ashwin Chaugule");
906 MODULE_DESCRIPTION("CPUFreq driver based on the ACPI CPPC v5.0+ spec");
907 MODULE_LICENSE("GPL");
908
909 late_initcall(cppc_cpufreq_init);
910
911 static const struct acpi_device_id cppc_acpi_ids[] __used = {
912         {ACPI_PROCESSOR_DEVICE_HID, },
913         {}
914 };
915
916 MODULE_DEVICE_TABLE(acpi, cppc_acpi_ids);
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