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 <ashwin.chaugule@linaro.org>
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/dmi.h>
20 #include <linux/irq_work.h>
21 #include <linux/kthread.h>
22 #include <linux/time.h>
23 #include <linux/vmalloc.h>
24 #include <uapi/linux/sched/types.h>
25
26 #include <asm/unaligned.h>
27
28 #include <acpi/cppc_acpi.h>
29
30 /* Minimum struct length needed for the DMI processor entry we want */
31 #define DMI_ENTRY_PROCESSOR_MIN_LENGTH 48
32
33 /* Offset in the DMI processor structure for the max frequency */
34 #define DMI_PROCESSOR_MAX_SPEED 0x14
35
36 /*
37 * This list contains information parsed from per CPU ACPI _CPC and _PSD
38 * structures: e.g. the highest and lowest supported performance, capabilities,
39 * desired performance, level requested etc. Depending on the share_type, not
40 * all CPUs will have an entry in the list.
41 */
42 static LIST_HEAD(cpu_data_list);
43
44 static bool boost_supported;
45
46 struct cppc_workaround_oem_info {
47 char oem_id[ACPI_OEM_ID_SIZE + 1];
48 char oem_table_id[ACPI_OEM_TABLE_ID_SIZE + 1];
49 u32 oem_revision;
50 };
51
52 static struct cppc_workaround_oem_info wa_info[] = {
53 {
54 .oem_id = "HISI ",
55 .oem_table_id = "HIP07 ",
56 .oem_revision = 0,
57 }, {
58 .oem_id = "HISI ",
59 .oem_table_id = "HIP08 ",
60 .oem_revision = 0,
61 }
62 };
63
64 static struct cpufreq_driver cppc_cpufreq_driver;
65
66 static enum {
67 FIE_UNSET = -1,
68 FIE_ENABLED,
69 FIE_DISABLED
70 } fie_disabled = FIE_UNSET;
71
72 #ifdef CONFIG_ACPI_CPPC_CPUFREQ_FIE
73 module_param(fie_disabled, int, 0444);
74 MODULE_PARM_DESC(fie_disabled, "Disable Frequency Invariance Engine (FIE)");
75
76 /* Frequency invariance support */
77 struct cppc_freq_invariance {
78 int cpu;
79 struct irq_work irq_work;
80 struct kthread_work work;
81 struct cppc_perf_fb_ctrs prev_perf_fb_ctrs;
82 struct cppc_cpudata *cpu_data;
83 };
84
85 static DEFINE_PER_CPU(struct cppc_freq_invariance, cppc_freq_inv);
86 static struct kthread_worker *kworker_fie;
87
88 static unsigned int hisi_cppc_cpufreq_get_rate(unsigned int cpu);
89 static int cppc_perf_from_fbctrs(struct cppc_cpudata *cpu_data,
90 struct cppc_perf_fb_ctrs *fb_ctrs_t0,
91 struct cppc_perf_fb_ctrs *fb_ctrs_t1);
92
93 /**
94 * cppc_scale_freq_workfn - CPPC arch_freq_scale updater for frequency invariance
95 * @work: The work item.
96 *
97 * The CPPC driver register itself with the topology core to provide its own
98 * implementation (cppc_scale_freq_tick()) of topology_scale_freq_tick() which
99 * gets called by the scheduler on every tick.
100 *
101 * Note that the arch specific counters have higher priority than CPPC counters,
102 * if available, though the CPPC driver doesn't need to have any special
103 * handling for that.
104 *
105 * On an invocation of cppc_scale_freq_tick(), we schedule an irq work (since we
106 * reach here from hard-irq context), which then schedules a normal work item
107 * and cppc_scale_freq_workfn() updates the per_cpu arch_freq_scale variable
108 * based on the counter updates since the last tick.
109 */
cppc_scale_freq_workfn(struct kthread_work * work)110 static void cppc_scale_freq_workfn(struct kthread_work *work)
111 {
112 struct cppc_freq_invariance *cppc_fi;
113 struct cppc_perf_fb_ctrs fb_ctrs = {0};
114 struct cppc_cpudata *cpu_data;
115 unsigned long local_freq_scale;
116 u64 perf;
117
118 cppc_fi = container_of(work, struct cppc_freq_invariance, work);
119 cpu_data = cppc_fi->cpu_data;
120
121 if (cppc_get_perf_ctrs(cppc_fi->cpu, &fb_ctrs)) {
122 pr_warn("%s: failed to read perf counters\n", __func__);
123 return;
124 }
125
126 perf = cppc_perf_from_fbctrs(cpu_data, &cppc_fi->prev_perf_fb_ctrs,
127 &fb_ctrs);
128 cppc_fi->prev_perf_fb_ctrs = fb_ctrs;
129
130 perf <<= SCHED_CAPACITY_SHIFT;
131 local_freq_scale = div64_u64(perf, cpu_data->perf_caps.highest_perf);
132
133 /* This can happen due to counter's overflow */
134 if (unlikely(local_freq_scale > 1024))
135 local_freq_scale = 1024;
136
137 per_cpu(arch_freq_scale, cppc_fi->cpu) = local_freq_scale;
138 }
139
cppc_irq_work(struct irq_work * irq_work)140 static void cppc_irq_work(struct irq_work *irq_work)
141 {
142 struct cppc_freq_invariance *cppc_fi;
143
144 cppc_fi = container_of(irq_work, struct cppc_freq_invariance, irq_work);
145 kthread_queue_work(kworker_fie, &cppc_fi->work);
146 }
147
cppc_scale_freq_tick(void)148 static void cppc_scale_freq_tick(void)
149 {
150 struct cppc_freq_invariance *cppc_fi = &per_cpu(cppc_freq_inv, smp_processor_id());
151
152 /*
153 * cppc_get_perf_ctrs() can potentially sleep, call that from the right
154 * context.
155 */
156 irq_work_queue(&cppc_fi->irq_work);
157 }
158
159 static struct scale_freq_data cppc_sftd = {
160 .source = SCALE_FREQ_SOURCE_CPPC,
161 .set_freq_scale = cppc_scale_freq_tick,
162 };
163
cppc_cpufreq_cpu_fie_init(struct cpufreq_policy * policy)164 static void cppc_cpufreq_cpu_fie_init(struct cpufreq_policy *policy)
165 {
166 struct cppc_freq_invariance *cppc_fi;
167 int cpu, ret;
168
169 if (fie_disabled)
170 return;
171
172 for_each_cpu(cpu, policy->cpus) {
173 cppc_fi = &per_cpu(cppc_freq_inv, cpu);
174 cppc_fi->cpu = cpu;
175 cppc_fi->cpu_data = policy->driver_data;
176 kthread_init_work(&cppc_fi->work, cppc_scale_freq_workfn);
177 init_irq_work(&cppc_fi->irq_work, cppc_irq_work);
178
179 ret = cppc_get_perf_ctrs(cpu, &cppc_fi->prev_perf_fb_ctrs);
180 if (ret) {
181 pr_warn("%s: failed to read perf counters for cpu:%d: %d\n",
182 __func__, cpu, ret);
183
184 /*
185 * Don't abort if the CPU was offline while the driver
186 * was getting registered.
187 */
188 if (cpu_online(cpu))
189 return;
190 }
191 }
192
193 /* Register for freq-invariance */
194 topology_set_scale_freq_source(&cppc_sftd, policy->cpus);
195 }
196
197 /*
198 * We free all the resources on policy's removal and not on CPU removal as the
199 * irq-work are per-cpu and the hotplug core takes care of flushing the pending
200 * irq-works (hint: smpcfd_dying_cpu()) on CPU hotplug. Even if the kthread-work
201 * fires on another CPU after the concerned CPU is removed, it won't harm.
202 *
203 * We just need to make sure to remove them all on policy->exit().
204 */
cppc_cpufreq_cpu_fie_exit(struct cpufreq_policy * policy)205 static void cppc_cpufreq_cpu_fie_exit(struct cpufreq_policy *policy)
206 {
207 struct cppc_freq_invariance *cppc_fi;
208 int cpu;
209
210 if (fie_disabled)
211 return;
212
213 /* policy->cpus will be empty here, use related_cpus instead */
214 topology_clear_scale_freq_source(SCALE_FREQ_SOURCE_CPPC, policy->related_cpus);
215
216 for_each_cpu(cpu, policy->related_cpus) {
217 cppc_fi = &per_cpu(cppc_freq_inv, cpu);
218 irq_work_sync(&cppc_fi->irq_work);
219 kthread_cancel_work_sync(&cppc_fi->work);
220 }
221 }
222
cppc_freq_invariance_init(void)223 static void __init cppc_freq_invariance_init(void)
224 {
225 struct sched_attr attr = {
226 .size = sizeof(struct sched_attr),
227 .sched_policy = SCHED_DEADLINE,
228 .sched_nice = 0,
229 .sched_priority = 0,
230 /*
231 * Fake (unused) bandwidth; workaround to "fix"
232 * priority inheritance.
233 */
234 .sched_runtime = 1000000,
235 .sched_deadline = 10000000,
236 .sched_period = 10000000,
237 };
238 int ret;
239
240 if (fie_disabled != FIE_ENABLED && fie_disabled != FIE_DISABLED) {
241 fie_disabled = FIE_ENABLED;
242 if (cppc_perf_ctrs_in_pcc()) {
243 pr_info("FIE not enabled on systems with registers in PCC\n");
244 fie_disabled = FIE_DISABLED;
245 }
246 }
247
248 if (fie_disabled)
249 return;
250
251 kworker_fie = kthread_create_worker(0, "cppc_fie");
252 if (IS_ERR(kworker_fie)) {
253 pr_warn("%s: failed to create kworker_fie: %ld\n", __func__,
254 PTR_ERR(kworker_fie));
255 fie_disabled = FIE_DISABLED;
256 return;
257 }
258
259 ret = sched_setattr_nocheck(kworker_fie->task, &attr);
260 if (ret) {
261 pr_warn("%s: failed to set SCHED_DEADLINE: %d\n", __func__,
262 ret);
263 kthread_destroy_worker(kworker_fie);
264 fie_disabled = FIE_DISABLED;
265 }
266 }
267
cppc_freq_invariance_exit(void)268 static void cppc_freq_invariance_exit(void)
269 {
270 if (fie_disabled)
271 return;
272
273 kthread_destroy_worker(kworker_fie);
274 }
275
276 #else
cppc_cpufreq_cpu_fie_init(struct cpufreq_policy * policy)277 static inline void cppc_cpufreq_cpu_fie_init(struct cpufreq_policy *policy)
278 {
279 }
280
cppc_cpufreq_cpu_fie_exit(struct cpufreq_policy * policy)281 static inline void cppc_cpufreq_cpu_fie_exit(struct cpufreq_policy *policy)
282 {
283 }
284
cppc_freq_invariance_init(void)285 static inline void cppc_freq_invariance_init(void)
286 {
287 }
288
cppc_freq_invariance_exit(void)289 static inline void cppc_freq_invariance_exit(void)
290 {
291 }
292 #endif /* CONFIG_ACPI_CPPC_CPUFREQ_FIE */
293
294 /* Callback function used to retrieve the max frequency from DMI */
cppc_find_dmi_mhz(const struct dmi_header * dm,void * private)295 static void cppc_find_dmi_mhz(const struct dmi_header *dm, void *private)
296 {
297 const u8 *dmi_data = (const u8 *)dm;
298 u16 *mhz = (u16 *)private;
299
300 if (dm->type == DMI_ENTRY_PROCESSOR &&
301 dm->length >= DMI_ENTRY_PROCESSOR_MIN_LENGTH) {
302 u16 val = (u16)get_unaligned((const u16 *)
303 (dmi_data + DMI_PROCESSOR_MAX_SPEED));
304 *mhz = val > *mhz ? val : *mhz;
305 }
306 }
307
308 /* Look up the max frequency in DMI */
cppc_get_dmi_max_khz(void)309 static u64 cppc_get_dmi_max_khz(void)
310 {
311 u16 mhz = 0;
312
313 dmi_walk(cppc_find_dmi_mhz, &mhz);
314
315 /*
316 * Real stupid fallback value, just in case there is no
317 * actual value set.
318 */
319 mhz = mhz ? mhz : 1;
320
321 return (1000 * mhz);
322 }
323
324 /*
325 * If CPPC lowest_freq and nominal_freq registers are exposed then we can
326 * use them to convert perf to freq and vice versa. The conversion is
327 * extrapolated as an affine function passing by the 2 points:
328 * - (Low perf, Low freq)
329 * - (Nominal perf, Nominal perf)
330 */
cppc_cpufreq_perf_to_khz(struct cppc_cpudata * cpu_data,unsigned int perf)331 static unsigned int cppc_cpufreq_perf_to_khz(struct cppc_cpudata *cpu_data,
332 unsigned int perf)
333 {
334 struct cppc_perf_caps *caps = &cpu_data->perf_caps;
335 s64 retval, offset = 0;
336 static u64 max_khz;
337 u64 mul, div;
338
339 if (caps->lowest_freq && caps->nominal_freq) {
340 mul = caps->nominal_freq - caps->lowest_freq;
341 div = caps->nominal_perf - caps->lowest_perf;
342 offset = caps->nominal_freq - div64_u64(caps->nominal_perf * mul, div);
343 } else {
344 if (!max_khz)
345 max_khz = cppc_get_dmi_max_khz();
346 mul = max_khz;
347 div = caps->highest_perf;
348 }
349
350 retval = offset + div64_u64(perf * mul, div);
351 if (retval >= 0)
352 return retval;
353 return 0;
354 }
355
cppc_cpufreq_khz_to_perf(struct cppc_cpudata * cpu_data,unsigned int freq)356 static unsigned int cppc_cpufreq_khz_to_perf(struct cppc_cpudata *cpu_data,
357 unsigned int freq)
358 {
359 struct cppc_perf_caps *caps = &cpu_data->perf_caps;
360 s64 retval, offset = 0;
361 static u64 max_khz;
362 u64 mul, div;
363
364 if (caps->lowest_freq && caps->nominal_freq) {
365 mul = caps->nominal_perf - caps->lowest_perf;
366 div = caps->nominal_freq - caps->lowest_freq;
367 offset = caps->nominal_perf - div64_u64(caps->nominal_freq * mul, div);
368 } else {
369 if (!max_khz)
370 max_khz = cppc_get_dmi_max_khz();
371 mul = caps->highest_perf;
372 div = max_khz;
373 }
374
375 retval = offset + div64_u64(freq * mul, div);
376 if (retval >= 0)
377 return retval;
378 return 0;
379 }
380
cppc_cpufreq_set_target(struct cpufreq_policy * policy,unsigned int target_freq,unsigned int relation)381 static int cppc_cpufreq_set_target(struct cpufreq_policy *policy,
382 unsigned int target_freq,
383 unsigned int relation)
384
385 {
386 struct cppc_cpudata *cpu_data = policy->driver_data;
387 unsigned int cpu = policy->cpu;
388 struct cpufreq_freqs freqs;
389 u32 desired_perf;
390 int ret = 0;
391
392 desired_perf = cppc_cpufreq_khz_to_perf(cpu_data, target_freq);
393 /* Return if it is exactly the same perf */
394 if (desired_perf == cpu_data->perf_ctrls.desired_perf)
395 return ret;
396
397 cpu_data->perf_ctrls.desired_perf = desired_perf;
398 freqs.old = policy->cur;
399 freqs.new = target_freq;
400
401 cpufreq_freq_transition_begin(policy, &freqs);
402 ret = cppc_set_perf(cpu, &cpu_data->perf_ctrls);
403 cpufreq_freq_transition_end(policy, &freqs, ret != 0);
404
405 if (ret)
406 pr_debug("Failed to set target on CPU:%d. ret:%d\n",
407 cpu, ret);
408
409 return ret;
410 }
411
cppc_cpufreq_fast_switch(struct cpufreq_policy * policy,unsigned int target_freq)412 static unsigned int cppc_cpufreq_fast_switch(struct cpufreq_policy *policy,
413 unsigned int target_freq)
414 {
415 struct cppc_cpudata *cpu_data = policy->driver_data;
416 unsigned int cpu = policy->cpu;
417 u32 desired_perf;
418 int ret;
419
420 desired_perf = cppc_cpufreq_khz_to_perf(cpu_data, target_freq);
421 cpu_data->perf_ctrls.desired_perf = desired_perf;
422 ret = cppc_set_perf(cpu, &cpu_data->perf_ctrls);
423
424 if (ret) {
425 pr_debug("Failed to set target on CPU:%d. ret:%d\n",
426 cpu, ret);
427 return 0;
428 }
429
430 return target_freq;
431 }
432
cppc_verify_policy(struct cpufreq_policy_data * policy)433 static int cppc_verify_policy(struct cpufreq_policy_data *policy)
434 {
435 cpufreq_verify_within_cpu_limits(policy);
436 return 0;
437 }
438
439 /*
440 * The PCC subspace describes the rate at which platform can accept commands
441 * on the shared PCC channel (including READs which do not count towards freq
442 * transition requests), so ideally we need to use the PCC values as a fallback
443 * if we don't have a platform specific transition_delay_us
444 */
445 #ifdef CONFIG_ARM64
446 #include <asm/cputype.h>
447
cppc_cpufreq_get_transition_delay_us(unsigned int cpu)448 static unsigned int cppc_cpufreq_get_transition_delay_us(unsigned int cpu)
449 {
450 unsigned long implementor = read_cpuid_implementor();
451 unsigned long part_num = read_cpuid_part_number();
452
453 switch (implementor) {
454 case ARM_CPU_IMP_QCOM:
455 switch (part_num) {
456 case QCOM_CPU_PART_FALKOR_V1:
457 case QCOM_CPU_PART_FALKOR:
458 return 10000;
459 }
460 }
461 return cppc_get_transition_latency(cpu) / NSEC_PER_USEC;
462 }
463 #else
cppc_cpufreq_get_transition_delay_us(unsigned int cpu)464 static unsigned int cppc_cpufreq_get_transition_delay_us(unsigned int cpu)
465 {
466 return cppc_get_transition_latency(cpu) / NSEC_PER_USEC;
467 }
468 #endif
469
470 #if defined(CONFIG_ARM64) && defined(CONFIG_ENERGY_MODEL)
471
472 static DEFINE_PER_CPU(unsigned int, efficiency_class);
473 static void cppc_cpufreq_register_em(struct cpufreq_policy *policy);
474
475 /* Create an artificial performance state every CPPC_EM_CAP_STEP capacity unit. */
476 #define CPPC_EM_CAP_STEP (20)
477 /* Increase the cost value by CPPC_EM_COST_STEP every performance state. */
478 #define CPPC_EM_COST_STEP (1)
479 /* Add a cost gap correspnding to the energy of 4 CPUs. */
480 #define CPPC_EM_COST_GAP (4 * SCHED_CAPACITY_SCALE * CPPC_EM_COST_STEP \
481 / CPPC_EM_CAP_STEP)
482
get_perf_level_count(struct cpufreq_policy * policy)483 static unsigned int get_perf_level_count(struct cpufreq_policy *policy)
484 {
485 struct cppc_perf_caps *perf_caps;
486 unsigned int min_cap, max_cap;
487 struct cppc_cpudata *cpu_data;
488 int cpu = policy->cpu;
489
490 cpu_data = policy->driver_data;
491 perf_caps = &cpu_data->perf_caps;
492 max_cap = arch_scale_cpu_capacity(cpu);
493 min_cap = div_u64((u64)max_cap * perf_caps->lowest_perf,
494 perf_caps->highest_perf);
495 if ((min_cap == 0) || (max_cap < min_cap))
496 return 0;
497 return 1 + max_cap / CPPC_EM_CAP_STEP - min_cap / CPPC_EM_CAP_STEP;
498 }
499
500 /*
501 * The cost is defined as:
502 * cost = power * max_frequency / frequency
503 */
compute_cost(int cpu,int step)504 static inline unsigned long compute_cost(int cpu, int step)
505 {
506 return CPPC_EM_COST_GAP * per_cpu(efficiency_class, cpu) +
507 step * CPPC_EM_COST_STEP;
508 }
509
cppc_get_cpu_power(struct device * cpu_dev,unsigned long * power,unsigned long * KHz)510 static int cppc_get_cpu_power(struct device *cpu_dev,
511 unsigned long *power, unsigned long *KHz)
512 {
513 unsigned long perf_step, perf_prev, perf, perf_check;
514 unsigned int min_step, max_step, step, step_check;
515 unsigned long prev_freq = *KHz;
516 unsigned int min_cap, max_cap;
517 struct cpufreq_policy *policy;
518
519 struct cppc_perf_caps *perf_caps;
520 struct cppc_cpudata *cpu_data;
521
522 policy = cpufreq_cpu_get_raw(cpu_dev->id);
523 cpu_data = policy->driver_data;
524 perf_caps = &cpu_data->perf_caps;
525 max_cap = arch_scale_cpu_capacity(cpu_dev->id);
526 min_cap = div_u64((u64)max_cap * perf_caps->lowest_perf,
527 perf_caps->highest_perf);
528 perf_step = div_u64((u64)CPPC_EM_CAP_STEP * perf_caps->highest_perf,
529 max_cap);
530 min_step = min_cap / CPPC_EM_CAP_STEP;
531 max_step = max_cap / CPPC_EM_CAP_STEP;
532
533 perf_prev = cppc_cpufreq_khz_to_perf(cpu_data, *KHz);
534 step = perf_prev / perf_step;
535
536 if (step > max_step)
537 return -EINVAL;
538
539 if (min_step == max_step) {
540 step = max_step;
541 perf = perf_caps->highest_perf;
542 } else if (step < min_step) {
543 step = min_step;
544 perf = perf_caps->lowest_perf;
545 } else {
546 step++;
547 if (step == max_step)
548 perf = perf_caps->highest_perf;
549 else
550 perf = step * perf_step;
551 }
552
553 *KHz = cppc_cpufreq_perf_to_khz(cpu_data, perf);
554 perf_check = cppc_cpufreq_khz_to_perf(cpu_data, *KHz);
555 step_check = perf_check / perf_step;
556
557 /*
558 * To avoid bad integer approximation, check that new frequency value
559 * increased and that the new frequency will be converted to the
560 * desired step value.
561 */
562 while ((*KHz == prev_freq) || (step_check != step)) {
563 perf++;
564 *KHz = cppc_cpufreq_perf_to_khz(cpu_data, perf);
565 perf_check = cppc_cpufreq_khz_to_perf(cpu_data, *KHz);
566 step_check = perf_check / perf_step;
567 }
568
569 /*
570 * With an artificial EM, only the cost value is used. Still the power
571 * is populated such as 0 < power < EM_MAX_POWER. This allows to add
572 * more sense to the artificial performance states.
573 */
574 *power = compute_cost(cpu_dev->id, step);
575
576 return 0;
577 }
578
cppc_get_cpu_cost(struct device * cpu_dev,unsigned long KHz,unsigned long * cost)579 static int cppc_get_cpu_cost(struct device *cpu_dev, unsigned long KHz,
580 unsigned long *cost)
581 {
582 unsigned long perf_step, perf_prev;
583 struct cppc_perf_caps *perf_caps;
584 struct cpufreq_policy *policy;
585 struct cppc_cpudata *cpu_data;
586 unsigned int max_cap;
587 int step;
588
589 policy = cpufreq_cpu_get_raw(cpu_dev->id);
590 cpu_data = policy->driver_data;
591 perf_caps = &cpu_data->perf_caps;
592 max_cap = arch_scale_cpu_capacity(cpu_dev->id);
593
594 perf_prev = cppc_cpufreq_khz_to_perf(cpu_data, KHz);
595 perf_step = CPPC_EM_CAP_STEP * perf_caps->highest_perf / max_cap;
596 step = perf_prev / perf_step;
597
598 *cost = compute_cost(cpu_dev->id, step);
599
600 return 0;
601 }
602
populate_efficiency_class(void)603 static int populate_efficiency_class(void)
604 {
605 struct acpi_madt_generic_interrupt *gicc;
606 DECLARE_BITMAP(used_classes, 256) = {};
607 int class, cpu, index;
608
609 for_each_possible_cpu(cpu) {
610 gicc = acpi_cpu_get_madt_gicc(cpu);
611 class = gicc->efficiency_class;
612 bitmap_set(used_classes, class, 1);
613 }
614
615 if (bitmap_weight(used_classes, 256) <= 1) {
616 pr_debug("Efficiency classes are all equal (=%d). "
617 "No EM registered", class);
618 return -EINVAL;
619 }
620
621 /*
622 * Squeeze efficiency class values on [0:#efficiency_class-1].
623 * Values are per spec in [0:255].
624 */
625 index = 0;
626 for_each_set_bit(class, used_classes, 256) {
627 for_each_possible_cpu(cpu) {
628 gicc = acpi_cpu_get_madt_gicc(cpu);
629 if (gicc->efficiency_class == class)
630 per_cpu(efficiency_class, cpu) = index;
631 }
632 index++;
633 }
634 cppc_cpufreq_driver.register_em = cppc_cpufreq_register_em;
635
636 return 0;
637 }
638
cppc_cpufreq_register_em(struct cpufreq_policy * policy)639 static void cppc_cpufreq_register_em(struct cpufreq_policy *policy)
640 {
641 struct cppc_cpudata *cpu_data;
642 struct em_data_callback em_cb =
643 EM_ADV_DATA_CB(cppc_get_cpu_power, cppc_get_cpu_cost);
644
645 cpu_data = policy->driver_data;
646 em_dev_register_perf_domain(get_cpu_device(policy->cpu),
647 get_perf_level_count(policy), &em_cb,
648 cpu_data->shared_cpu_map, 0);
649 }
650
651 #else
populate_efficiency_class(void)652 static int populate_efficiency_class(void)
653 {
654 return 0;
655 }
656 #endif
657
cppc_cpufreq_get_cpu_data(unsigned int cpu)658 static struct cppc_cpudata *cppc_cpufreq_get_cpu_data(unsigned int cpu)
659 {
660 struct cppc_cpudata *cpu_data;
661 int ret;
662
663 cpu_data = kzalloc(sizeof(struct cppc_cpudata), GFP_KERNEL);
664 if (!cpu_data)
665 goto out;
666
667 if (!zalloc_cpumask_var(&cpu_data->shared_cpu_map, GFP_KERNEL))
668 goto free_cpu;
669
670 ret = acpi_get_psd_map(cpu, cpu_data);
671 if (ret) {
672 pr_debug("Err parsing CPU%d PSD data: ret:%d\n", cpu, ret);
673 goto free_mask;
674 }
675
676 ret = cppc_get_perf_caps(cpu, &cpu_data->perf_caps);
677 if (ret) {
678 pr_debug("Err reading CPU%d perf caps: ret:%d\n", cpu, ret);
679 goto free_mask;
680 }
681
682 /* Convert the lowest and nominal freq from MHz to KHz */
683 cpu_data->perf_caps.lowest_freq *= 1000;
684 cpu_data->perf_caps.nominal_freq *= 1000;
685
686 list_add(&cpu_data->node, &cpu_data_list);
687
688 return cpu_data;
689
690 free_mask:
691 free_cpumask_var(cpu_data->shared_cpu_map);
692 free_cpu:
693 kfree(cpu_data);
694 out:
695 return NULL;
696 }
697
cppc_cpufreq_put_cpu_data(struct cpufreq_policy * policy)698 static void cppc_cpufreq_put_cpu_data(struct cpufreq_policy *policy)
699 {
700 struct cppc_cpudata *cpu_data = policy->driver_data;
701
702 list_del(&cpu_data->node);
703 free_cpumask_var(cpu_data->shared_cpu_map);
704 kfree(cpu_data);
705 policy->driver_data = NULL;
706 }
707
cppc_cpufreq_cpu_init(struct cpufreq_policy * policy)708 static int cppc_cpufreq_cpu_init(struct cpufreq_policy *policy)
709 {
710 unsigned int cpu = policy->cpu;
711 struct cppc_cpudata *cpu_data;
712 struct cppc_perf_caps *caps;
713 int ret;
714
715 cpu_data = cppc_cpufreq_get_cpu_data(cpu);
716 if (!cpu_data) {
717 pr_err("Error in acquiring _CPC/_PSD data for CPU%d.\n", cpu);
718 return -ENODEV;
719 }
720 caps = &cpu_data->perf_caps;
721 policy->driver_data = cpu_data;
722
723 /*
724 * Set min to lowest nonlinear perf to avoid any efficiency penalty (see
725 * Section 8.4.7.1.1.5 of ACPI 6.1 spec)
726 */
727 policy->min = cppc_cpufreq_perf_to_khz(cpu_data,
728 caps->lowest_nonlinear_perf);
729 policy->max = cppc_cpufreq_perf_to_khz(cpu_data,
730 caps->nominal_perf);
731
732 /*
733 * Set cpuinfo.min_freq to Lowest to make the full range of performance
734 * available if userspace wants to use any perf between lowest & lowest
735 * nonlinear perf
736 */
737 policy->cpuinfo.min_freq = cppc_cpufreq_perf_to_khz(cpu_data,
738 caps->lowest_perf);
739 policy->cpuinfo.max_freq = cppc_cpufreq_perf_to_khz(cpu_data,
740 caps->nominal_perf);
741
742 policy->transition_delay_us = cppc_cpufreq_get_transition_delay_us(cpu);
743 policy->shared_type = cpu_data->shared_type;
744
745 switch (policy->shared_type) {
746 case CPUFREQ_SHARED_TYPE_HW:
747 case CPUFREQ_SHARED_TYPE_NONE:
748 /* Nothing to be done - we'll have a policy for each CPU */
749 break;
750 case CPUFREQ_SHARED_TYPE_ANY:
751 /*
752 * All CPUs in the domain will share a policy and all cpufreq
753 * operations will use a single cppc_cpudata structure stored
754 * in policy->driver_data.
755 */
756 cpumask_copy(policy->cpus, cpu_data->shared_cpu_map);
757 break;
758 default:
759 pr_debug("Unsupported CPU co-ord type: %d\n",
760 policy->shared_type);
761 ret = -EFAULT;
762 goto out;
763 }
764
765 policy->fast_switch_possible = cppc_allow_fast_switch();
766 policy->dvfs_possible_from_any_cpu = true;
767
768 /*
769 * If 'highest_perf' is greater than 'nominal_perf', we assume CPU Boost
770 * is supported.
771 */
772 if (caps->highest_perf > caps->nominal_perf)
773 boost_supported = true;
774
775 /* Set policy->cur to max now. The governors will adjust later. */
776 policy->cur = cppc_cpufreq_perf_to_khz(cpu_data, caps->highest_perf);
777 cpu_data->perf_ctrls.desired_perf = caps->highest_perf;
778
779 ret = cppc_set_perf(cpu, &cpu_data->perf_ctrls);
780 if (ret) {
781 pr_debug("Err setting perf value:%d on CPU:%d. ret:%d\n",
782 caps->highest_perf, cpu, ret);
783 goto out;
784 }
785
786 cppc_cpufreq_cpu_fie_init(policy);
787 return 0;
788
789 out:
790 cppc_cpufreq_put_cpu_data(policy);
791 return ret;
792 }
793
cppc_cpufreq_cpu_exit(struct cpufreq_policy * policy)794 static int cppc_cpufreq_cpu_exit(struct cpufreq_policy *policy)
795 {
796 struct cppc_cpudata *cpu_data = policy->driver_data;
797 struct cppc_perf_caps *caps = &cpu_data->perf_caps;
798 unsigned int cpu = policy->cpu;
799 int ret;
800
801 cppc_cpufreq_cpu_fie_exit(policy);
802
803 cpu_data->perf_ctrls.desired_perf = caps->lowest_perf;
804
805 ret = cppc_set_perf(cpu, &cpu_data->perf_ctrls);
806 if (ret)
807 pr_debug("Err setting perf value:%d on CPU:%d. ret:%d\n",
808 caps->lowest_perf, cpu, ret);
809
810 cppc_cpufreq_put_cpu_data(policy);
811 return 0;
812 }
813
get_delta(u64 t1,u64 t0)814 static inline u64 get_delta(u64 t1, u64 t0)
815 {
816 if (t1 > t0 || t0 > ~(u32)0)
817 return t1 - t0;
818
819 return (u32)t1 - (u32)t0;
820 }
821
cppc_perf_from_fbctrs(struct cppc_cpudata * cpu_data,struct cppc_perf_fb_ctrs * fb_ctrs_t0,struct cppc_perf_fb_ctrs * fb_ctrs_t1)822 static int cppc_perf_from_fbctrs(struct cppc_cpudata *cpu_data,
823 struct cppc_perf_fb_ctrs *fb_ctrs_t0,
824 struct cppc_perf_fb_ctrs *fb_ctrs_t1)
825 {
826 u64 delta_reference, delta_delivered;
827 u64 reference_perf;
828
829 reference_perf = fb_ctrs_t0->reference_perf;
830
831 delta_reference = get_delta(fb_ctrs_t1->reference,
832 fb_ctrs_t0->reference);
833 delta_delivered = get_delta(fb_ctrs_t1->delivered,
834 fb_ctrs_t0->delivered);
835
836 /* Check to avoid divide-by zero and invalid delivered_perf */
837 if (!delta_reference || !delta_delivered)
838 return cpu_data->perf_ctrls.desired_perf;
839
840 return (reference_perf * delta_delivered) / delta_reference;
841 }
842
cppc_cpufreq_get_rate(unsigned int cpu)843 static unsigned int cppc_cpufreq_get_rate(unsigned int cpu)
844 {
845 struct cppc_perf_fb_ctrs fb_ctrs_t0 = {0}, fb_ctrs_t1 = {0};
846 struct cpufreq_policy *policy = cpufreq_cpu_get(cpu);
847 struct cppc_cpudata *cpu_data;
848 u64 delivered_perf;
849 int ret;
850
851 if (!policy)
852 return -ENODEV;
853
854 cpu_data = policy->driver_data;
855
856 cpufreq_cpu_put(policy);
857
858 ret = cppc_get_perf_ctrs(cpu, &fb_ctrs_t0);
859 if (ret)
860 return 0;
861
862 udelay(2); /* 2usec delay between sampling */
863
864 ret = cppc_get_perf_ctrs(cpu, &fb_ctrs_t1);
865 if (ret)
866 return 0;
867
868 delivered_perf = cppc_perf_from_fbctrs(cpu_data, &fb_ctrs_t0,
869 &fb_ctrs_t1);
870
871 return cppc_cpufreq_perf_to_khz(cpu_data, delivered_perf);
872 }
873
cppc_cpufreq_set_boost(struct cpufreq_policy * policy,int state)874 static int cppc_cpufreq_set_boost(struct cpufreq_policy *policy, int state)
875 {
876 struct cppc_cpudata *cpu_data = policy->driver_data;
877 struct cppc_perf_caps *caps = &cpu_data->perf_caps;
878 int ret;
879
880 if (!boost_supported) {
881 pr_err("BOOST not supported by CPU or firmware\n");
882 return -EINVAL;
883 }
884
885 if (state)
886 policy->max = cppc_cpufreq_perf_to_khz(cpu_data,
887 caps->highest_perf);
888 else
889 policy->max = cppc_cpufreq_perf_to_khz(cpu_data,
890 caps->nominal_perf);
891 policy->cpuinfo.max_freq = policy->max;
892
893 ret = freq_qos_update_request(policy->max_freq_req, policy->max);
894 if (ret < 0)
895 return ret;
896
897 return 0;
898 }
899
show_freqdomain_cpus(struct cpufreq_policy * policy,char * buf)900 static ssize_t show_freqdomain_cpus(struct cpufreq_policy *policy, char *buf)
901 {
902 struct cppc_cpudata *cpu_data = policy->driver_data;
903
904 return cpufreq_show_cpus(cpu_data->shared_cpu_map, buf);
905 }
906 cpufreq_freq_attr_ro(freqdomain_cpus);
907
908 static struct freq_attr *cppc_cpufreq_attr[] = {
909 &freqdomain_cpus,
910 NULL,
911 };
912
913 static struct cpufreq_driver cppc_cpufreq_driver = {
914 .flags = CPUFREQ_CONST_LOOPS,
915 .verify = cppc_verify_policy,
916 .target = cppc_cpufreq_set_target,
917 .get = cppc_cpufreq_get_rate,
918 .fast_switch = cppc_cpufreq_fast_switch,
919 .init = cppc_cpufreq_cpu_init,
920 .exit = cppc_cpufreq_cpu_exit,
921 .set_boost = cppc_cpufreq_set_boost,
922 .attr = cppc_cpufreq_attr,
923 .name = "cppc_cpufreq",
924 };
925
926 /*
927 * HISI platform does not support delivered performance counter and
928 * reference performance counter. It can calculate the performance using the
929 * platform specific mechanism. We reuse the desired performance register to
930 * store the real performance calculated by the platform.
931 */
hisi_cppc_cpufreq_get_rate(unsigned int cpu)932 static unsigned int hisi_cppc_cpufreq_get_rate(unsigned int cpu)
933 {
934 struct cpufreq_policy *policy = cpufreq_cpu_get(cpu);
935 struct cppc_cpudata *cpu_data;
936 u64 desired_perf;
937 int ret;
938
939 if (!policy)
940 return -ENODEV;
941
942 cpu_data = policy->driver_data;
943
944 cpufreq_cpu_put(policy);
945
946 ret = cppc_get_desired_perf(cpu, &desired_perf);
947 if (ret < 0)
948 return -EIO;
949
950 return cppc_cpufreq_perf_to_khz(cpu_data, desired_perf);
951 }
952
cppc_check_hisi_workaround(void)953 static void cppc_check_hisi_workaround(void)
954 {
955 struct acpi_table_header *tbl;
956 acpi_status status = AE_OK;
957 int i;
958
959 status = acpi_get_table(ACPI_SIG_PCCT, 0, &tbl);
960 if (ACPI_FAILURE(status) || !tbl)
961 return;
962
963 for (i = 0; i < ARRAY_SIZE(wa_info); i++) {
964 if (!memcmp(wa_info[i].oem_id, tbl->oem_id, ACPI_OEM_ID_SIZE) &&
965 !memcmp(wa_info[i].oem_table_id, tbl->oem_table_id, ACPI_OEM_TABLE_ID_SIZE) &&
966 wa_info[i].oem_revision == tbl->oem_revision) {
967 /* Overwrite the get() callback */
968 cppc_cpufreq_driver.get = hisi_cppc_cpufreq_get_rate;
969 fie_disabled = FIE_DISABLED;
970 break;
971 }
972 }
973
974 acpi_put_table(tbl);
975 }
976
cppc_cpufreq_init(void)977 static int __init cppc_cpufreq_init(void)
978 {
979 int ret;
980
981 if (!acpi_cpc_valid())
982 return -ENODEV;
983
984 cppc_check_hisi_workaround();
985 cppc_freq_invariance_init();
986 populate_efficiency_class();
987
988 ret = cpufreq_register_driver(&cppc_cpufreq_driver);
989 if (ret)
990 cppc_freq_invariance_exit();
991
992 return ret;
993 }
994
free_cpu_data(void)995 static inline void free_cpu_data(void)
996 {
997 struct cppc_cpudata *iter, *tmp;
998
999 list_for_each_entry_safe(iter, tmp, &cpu_data_list, node) {
1000 free_cpumask_var(iter->shared_cpu_map);
1001 list_del(&iter->node);
1002 kfree(iter);
1003 }
1004
1005 }
1006
cppc_cpufreq_exit(void)1007 static void __exit cppc_cpufreq_exit(void)
1008 {
1009 cpufreq_unregister_driver(&cppc_cpufreq_driver);
1010 cppc_freq_invariance_exit();
1011
1012 free_cpu_data();
1013 }
1014
1015 module_exit(cppc_cpufreq_exit);
1016 MODULE_AUTHOR("Ashwin Chaugule");
1017 MODULE_DESCRIPTION("CPUFreq driver based on the ACPI CPPC v5.0+ spec");
1018 MODULE_LICENSE("GPL");
1019
1020 late_initcall(cppc_cpufreq_init);
1021
1022 static const struct acpi_device_id cppc_acpi_ids[] __used = {
1023 {ACPI_PROCESSOR_DEVICE_HID, },
1024 {}
1025 };
1026
1027 MODULE_DEVICE_TABLE(acpi, cppc_acpi_ids);
1028