1// SPDX-License-Identifier: GPL-2.0
2/*
3 * Copyright (c) 2020 - 2022, NVIDIA CORPORATION. All rights reserved
4 */
5
6#include <linux/cpu.h>
7#include <linux/cpufreq.h>
8#include <linux/dma-mapping.h>
9#include <linux/module.h>
10#include <linux/of.h>
11#include <linux/of_platform.h>
12#include <linux/platform_device.h>
13#include <linux/slab.h>
14#include <linux/units.h>
15
16#include <asm/smp_plat.h>
17
18#include <soc/tegra/bpmp.h>
19#include <soc/tegra/bpmp-abi.h>
20
21#define KHZ 1000
22#define REF_CLK_MHZ 408 /* 408 MHz */
23#define CPUFREQ_TBL_STEP_HZ (50 * KHZ * KHZ)
24#define MAX_CNT ~0U
25
26#define MAX_DELTA_KHZ 115200
27
28#define NDIV_MASK 0x1FF
29
30#define CORE_OFFSET(cpu) (cpu * 8)
31#define CMU_CLKS_BASE 0x2000
32#define SCRATCH_FREQ_CORE_REG(data, cpu) (data->regs + CMU_CLKS_BASE + CORE_OFFSET(cpu))
33
34#define MMCRAB_CLUSTER_BASE(cl) (0x30000 + (cl * 0x10000))
35#define CLUSTER_ACTMON_BASE(data, cl) \
36 (data->regs + (MMCRAB_CLUSTER_BASE(cl) + data->soc->actmon_cntr_base))
37#define CORE_ACTMON_CNTR_REG(data, cl, cpu) (CLUSTER_ACTMON_BASE(data, cl) + CORE_OFFSET(cpu))
38
39/* cpufreq transisition latency */
40#define TEGRA_CPUFREQ_TRANSITION_LATENCY (300 * 1000) /* unit in nanoseconds */
41
42struct tegra_cpu_data {
43 u32 cpuid;
44 u32 clusterid;
45 void __iomem *freq_core_reg;
46};
47
48struct tegra_cpu_ctr {
49 u32 cpu;
50 u32 coreclk_cnt, last_coreclk_cnt;
51 u32 refclk_cnt, last_refclk_cnt;
52};
53
54struct read_counters_work {
55 struct work_struct work;
56 struct tegra_cpu_ctr c;
57};
58
59struct tegra_cpufreq_ops {
60 void (*read_counters)(struct tegra_cpu_ctr *c);
61 void (*set_cpu_ndiv)(struct cpufreq_policy *policy, u64 ndiv);
62 void (*get_cpu_cluster_id)(u32 cpu, u32 *cpuid, u32 *clusterid);
63 int (*get_cpu_ndiv)(u32 cpu, u32 cpuid, u32 clusterid, u64 *ndiv);
64};
65
66struct tegra_cpufreq_soc {
67 struct tegra_cpufreq_ops *ops;
68 int maxcpus_per_cluster;
69 unsigned int num_clusters;
70 phys_addr_t actmon_cntr_base;
71 u32 refclk_delta_min;
72};
73
74struct tegra194_cpufreq_data {
75 void __iomem *regs;
76 struct cpufreq_frequency_table **bpmp_luts;
77 const struct tegra_cpufreq_soc *soc;
78 bool icc_dram_bw_scaling;
79 struct tegra_cpu_data *cpu_data;
80};
81
82static struct workqueue_struct *read_counters_wq;
83
84static int tegra_cpufreq_set_bw(struct cpufreq_policy *policy, unsigned long freq_khz)
85{
86 struct tegra194_cpufreq_data *data = cpufreq_get_driver_data();
87 struct dev_pm_opp *opp;
88 struct device *dev;
89 int ret;
90
91 dev = get_cpu_device(cpu: policy->cpu);
92 if (!dev)
93 return -ENODEV;
94
95 opp = dev_pm_opp_find_freq_exact(dev, freq: freq_khz * KHZ, available: true);
96 if (IS_ERR(ptr: opp))
97 return PTR_ERR(ptr: opp);
98
99 ret = dev_pm_opp_set_opp(dev, opp);
100 if (ret)
101 data->icc_dram_bw_scaling = false;
102
103 dev_pm_opp_put(opp);
104 return ret;
105}
106
107static void tegra_get_cpu_mpidr(void *mpidr)
108{
109 *((u64 *)mpidr) = read_cpuid_mpidr() & MPIDR_HWID_BITMASK;
110}
111
112static void tegra234_get_cpu_cluster_id(u32 cpu, u32 *cpuid, u32 *clusterid)
113{
114 u64 mpidr;
115
116 smp_call_function_single(cpuid: cpu, func: tegra_get_cpu_mpidr, info: &mpidr, wait: true);
117
118 if (cpuid)
119 *cpuid = MPIDR_AFFINITY_LEVEL(mpidr, 1);
120 if (clusterid)
121 *clusterid = MPIDR_AFFINITY_LEVEL(mpidr, 2);
122}
123
124static int tegra234_get_cpu_ndiv(u32 cpu, u32 cpuid, u32 clusterid, u64 *ndiv)
125{
126 struct tegra194_cpufreq_data *data = cpufreq_get_driver_data();
127
128 *ndiv = readl(addr: data->cpu_data[cpu].freq_core_reg) & NDIV_MASK;
129
130 return 0;
131}
132
133static void tegra234_set_cpu_ndiv(struct cpufreq_policy *policy, u64 ndiv)
134{
135 struct tegra194_cpufreq_data *data = cpufreq_get_driver_data();
136 u32 cpu;
137
138 for_each_cpu(cpu, policy->cpus)
139 writel(val: ndiv, addr: data->cpu_data[cpu].freq_core_reg);
140}
141
142/*
143 * This register provides access to two counter values with a single
144 * 64-bit read. The counter values are used to determine the average
145 * actual frequency a core has run at over a period of time.
146 * [63:32] PLLP counter: Counts at fixed frequency (408 MHz)
147 * [31:0] Core clock counter: Counts on every core clock cycle
148 */
149static void tegra234_read_counters(struct tegra_cpu_ctr *c)
150{
151 struct tegra194_cpufreq_data *data = cpufreq_get_driver_data();
152 void __iomem *actmon_reg;
153 u32 delta_refcnt;
154 int cnt = 0;
155 u64 val;
156
157 actmon_reg = CORE_ACTMON_CNTR_REG(data, data->cpu_data[c->cpu].clusterid,
158 data->cpu_data[c->cpu].cpuid);
159
160 val = readq(addr: actmon_reg);
161 c->last_refclk_cnt = upper_32_bits(val);
162 c->last_coreclk_cnt = lower_32_bits(val);
163
164 /*
165 * The sampling window is based on the minimum number of reference
166 * clock cycles which is known to give a stable value of CPU frequency.
167 */
168 do {
169 val = readq(addr: actmon_reg);
170 c->refclk_cnt = upper_32_bits(val);
171 c->coreclk_cnt = lower_32_bits(val);
172 if (c->refclk_cnt < c->last_refclk_cnt)
173 delta_refcnt = c->refclk_cnt + (MAX_CNT - c->last_refclk_cnt);
174 else
175 delta_refcnt = c->refclk_cnt - c->last_refclk_cnt;
176 if (++cnt >= 0xFFFF) {
177 pr_warn("cpufreq: problem with refclk on cpu:%d, delta_refcnt:%u, cnt:%d\n",
178 c->cpu, delta_refcnt, cnt);
179 break;
180 }
181 } while (delta_refcnt < data->soc->refclk_delta_min);
182}
183
184static struct tegra_cpufreq_ops tegra234_cpufreq_ops = {
185 .read_counters = tegra234_read_counters,
186 .get_cpu_cluster_id = tegra234_get_cpu_cluster_id,
187 .get_cpu_ndiv = tegra234_get_cpu_ndiv,
188 .set_cpu_ndiv = tegra234_set_cpu_ndiv,
189};
190
191static const struct tegra_cpufreq_soc tegra234_cpufreq_soc = {
192 .ops = &tegra234_cpufreq_ops,
193 .actmon_cntr_base = 0x9000,
194 .maxcpus_per_cluster = 4,
195 .num_clusters = 3,
196 .refclk_delta_min = 16000,
197};
198
199static const struct tegra_cpufreq_soc tegra239_cpufreq_soc = {
200 .ops = &tegra234_cpufreq_ops,
201 .actmon_cntr_base = 0x4000,
202 .maxcpus_per_cluster = 8,
203 .num_clusters = 1,
204 .refclk_delta_min = 16000,
205};
206
207static void tegra194_get_cpu_cluster_id(u32 cpu, u32 *cpuid, u32 *clusterid)
208{
209 u64 mpidr;
210
211 smp_call_function_single(cpuid: cpu, func: tegra_get_cpu_mpidr, info: &mpidr, wait: true);
212
213 if (cpuid)
214 *cpuid = MPIDR_AFFINITY_LEVEL(mpidr, 0);
215 if (clusterid)
216 *clusterid = MPIDR_AFFINITY_LEVEL(mpidr, 1);
217}
218
219/*
220 * Read per-core Read-only system register NVFREQ_FEEDBACK_EL1.
221 * The register provides frequency feedback information to
222 * determine the average actual frequency a core has run at over
223 * a period of time.
224 * [31:0] PLLP counter: Counts at fixed frequency (408 MHz)
225 * [63:32] Core clock counter: counts on every core clock cycle
226 * where the core is architecturally clocking
227 */
228static u64 read_freq_feedback(void)
229{
230 u64 val = 0;
231
232 asm volatile("mrs %0, s3_0_c15_c0_5" : "=r" (val) : );
233
234 return val;
235}
236
237static inline u32 map_ndiv_to_freq(struct mrq_cpu_ndiv_limits_response
238 *nltbl, u16 ndiv)
239{
240 return nltbl->ref_clk_hz / KHZ * ndiv / (nltbl->pdiv * nltbl->mdiv);
241}
242
243static void tegra194_read_counters(struct tegra_cpu_ctr *c)
244{
245 struct tegra194_cpufreq_data *data = cpufreq_get_driver_data();
246 u32 delta_refcnt;
247 int cnt = 0;
248 u64 val;
249
250 val = read_freq_feedback();
251 c->last_refclk_cnt = lower_32_bits(val);
252 c->last_coreclk_cnt = upper_32_bits(val);
253
254 /*
255 * The sampling window is based on the minimum number of reference
256 * clock cycles which is known to give a stable value of CPU frequency.
257 */
258 do {
259 val = read_freq_feedback();
260 c->refclk_cnt = lower_32_bits(val);
261 c->coreclk_cnt = upper_32_bits(val);
262 if (c->refclk_cnt < c->last_refclk_cnt)
263 delta_refcnt = c->refclk_cnt + (MAX_CNT - c->last_refclk_cnt);
264 else
265 delta_refcnt = c->refclk_cnt - c->last_refclk_cnt;
266 if (++cnt >= 0xFFFF) {
267 pr_warn("cpufreq: problem with refclk on cpu:%d, delta_refcnt:%u, cnt:%d\n",
268 c->cpu, delta_refcnt, cnt);
269 break;
270 }
271 } while (delta_refcnt < data->soc->refclk_delta_min);
272}
273
274static void tegra_read_counters(struct work_struct *work)
275{
276 struct tegra194_cpufreq_data *data = cpufreq_get_driver_data();
277 struct read_counters_work *read_counters_work;
278 struct tegra_cpu_ctr *c;
279
280 /*
281 * ref_clk_counter(32 bit counter) runs on constant clk,
282 * pll_p(408MHz).
283 * It will take = 2 ^ 32 / 408 MHz to overflow ref clk counter
284 * = 10526880 usec = 10.527 sec to overflow
285 *
286 * Like wise core_clk_counter(32 bit counter) runs on core clock.
287 * It's synchronized to crab_clk (cpu_crab_clk) which runs at
288 * freq of cluster. Assuming max cluster clock ~2000MHz,
289 * It will take = 2 ^ 32 / 2000 MHz to overflow core clk counter
290 * = ~2.147 sec to overflow
291 */
292 read_counters_work = container_of(work, struct read_counters_work,
293 work);
294 c = &read_counters_work->c;
295
296 data->soc->ops->read_counters(c);
297}
298
299/*
300 * Return instantaneous cpu speed
301 * Instantaneous freq is calculated as -
302 * -Takes sample on every query of getting the freq.
303 * - Read core and ref clock counters;
304 * - Delay for X us
305 * - Read above cycle counters again
306 * - Calculates freq by subtracting current and previous counters
307 * divided by the delay time or eqv. of ref_clk_counter in delta time
308 * - Return Kcycles/second, freq in KHz
309 *
310 * delta time period = x sec
311 * = delta ref_clk_counter / (408 * 10^6) sec
312 * freq in Hz = cycles/sec
313 * = (delta cycles / x sec
314 * = (delta cycles * 408 * 10^6) / delta ref_clk_counter
315 * in KHz = (delta cycles * 408 * 10^3) / delta ref_clk_counter
316 *
317 * @cpu - logical cpu whose freq to be updated
318 * Returns freq in KHz on success, 0 if cpu is offline
319 */
320static unsigned int tegra194_calculate_speed(u32 cpu)
321{
322 struct read_counters_work read_counters_work;
323 struct tegra_cpu_ctr c;
324 u32 delta_refcnt;
325 u32 delta_ccnt;
326 u32 rate_mhz;
327
328 /*
329 * Reconstruct cpu frequency over an observation/sampling window.
330 * Using workqueue to keep interrupts enabled during the interval.
331 */
332 read_counters_work.c.cpu = cpu;
333 INIT_WORK_ONSTACK(&read_counters_work.work, tegra_read_counters);
334 queue_work_on(cpu, wq: read_counters_wq, work: &read_counters_work.work);
335 flush_work(work: &read_counters_work.work);
336 c = read_counters_work.c;
337
338 if (c.coreclk_cnt < c.last_coreclk_cnt)
339 delta_ccnt = c.coreclk_cnt + (MAX_CNT - c.last_coreclk_cnt);
340 else
341 delta_ccnt = c.coreclk_cnt - c.last_coreclk_cnt;
342 if (!delta_ccnt)
343 return 0;
344
345 /* ref clock is 32 bits */
346 if (c.refclk_cnt < c.last_refclk_cnt)
347 delta_refcnt = c.refclk_cnt + (MAX_CNT - c.last_refclk_cnt);
348 else
349 delta_refcnt = c.refclk_cnt - c.last_refclk_cnt;
350 if (!delta_refcnt) {
351 pr_debug("cpufreq: %d is idle, delta_refcnt: 0\n", cpu);
352 return 0;
353 }
354 rate_mhz = ((unsigned long)(delta_ccnt * REF_CLK_MHZ)) / delta_refcnt;
355
356 return (rate_mhz * KHZ); /* in KHz */
357}
358
359static void tegra194_get_cpu_ndiv_sysreg(void *ndiv)
360{
361 u64 ndiv_val;
362
363 asm volatile("mrs %0, s3_0_c15_c0_4" : "=r" (ndiv_val) : );
364
365 *(u64 *)ndiv = ndiv_val;
366}
367
368static int tegra194_get_cpu_ndiv(u32 cpu, u32 cpuid, u32 clusterid, u64 *ndiv)
369{
370 return smp_call_function_single(cpuid: cpu, func: tegra194_get_cpu_ndiv_sysreg, info: &ndiv, wait: true);
371}
372
373static void tegra194_set_cpu_ndiv_sysreg(void *data)
374{
375 u64 ndiv_val = *(u64 *)data;
376
377 asm volatile("msr s3_0_c15_c0_4, %0" : : "r" (ndiv_val));
378}
379
380static void tegra194_set_cpu_ndiv(struct cpufreq_policy *policy, u64 ndiv)
381{
382 on_each_cpu_mask(mask: policy->cpus, func: tegra194_set_cpu_ndiv_sysreg, info: &ndiv, wait: true);
383}
384
385static unsigned int tegra194_get_speed(u32 cpu)
386{
387 struct tegra194_cpufreq_data *data = cpufreq_get_driver_data();
388 u32 clusterid = data->cpu_data[cpu].clusterid;
389 struct cpufreq_frequency_table *pos;
390 unsigned int rate;
391 u64 ndiv;
392 int ret;
393
394 /* reconstruct actual cpu freq using counters */
395 rate = tegra194_calculate_speed(cpu);
396
397 /* get last written ndiv value */
398 ret = data->soc->ops->get_cpu_ndiv(cpu, data->cpu_data[cpu].cpuid, clusterid, &ndiv);
399 if (WARN_ON_ONCE(ret))
400 return rate;
401
402 /*
403 * If the reconstructed frequency has acceptable delta from
404 * the last written value, then return freq corresponding
405 * to the last written ndiv value from freq_table. This is
406 * done to return consistent value.
407 */
408 cpufreq_for_each_valid_entry(pos, data->bpmp_luts[clusterid]) {
409 if (pos->driver_data != ndiv)
410 continue;
411
412 if (abs(pos->frequency - rate) > MAX_DELTA_KHZ) {
413 pr_warn("cpufreq: cpu%d,cur:%u,set:%u,delta:%d,set ndiv:%llu\n",
414 cpu, rate, pos->frequency, abs(rate - pos->frequency), ndiv);
415 } else {
416 rate = pos->frequency;
417 }
418 break;
419 }
420 return rate;
421}
422
423static int tegra_cpufreq_init_cpufreq_table(struct cpufreq_policy *policy,
424 struct cpufreq_frequency_table *bpmp_lut,
425 struct cpufreq_frequency_table **opp_table)
426{
427 struct tegra194_cpufreq_data *data = cpufreq_get_driver_data();
428 struct cpufreq_frequency_table *freq_table = NULL;
429 struct cpufreq_frequency_table *pos;
430 struct device *cpu_dev;
431 struct dev_pm_opp *opp;
432 unsigned long rate;
433 int ret, max_opps;
434 int j = 0;
435
436 cpu_dev = get_cpu_device(cpu: policy->cpu);
437 if (!cpu_dev) {
438 pr_err("%s: failed to get cpu%d device\n", __func__, policy->cpu);
439 return -ENODEV;
440 }
441
442 /* Initialize OPP table mentioned in operating-points-v2 property in DT */
443 ret = dev_pm_opp_of_add_table_indexed(dev: cpu_dev, index: 0);
444 if (!ret) {
445 max_opps = dev_pm_opp_get_opp_count(dev: cpu_dev);
446 if (max_opps <= 0) {
447 dev_err(cpu_dev, "Failed to add OPPs\n");
448 return max_opps;
449 }
450
451 /* Disable all opps and cross-validate against LUT later */
452 for (rate = 0; ; rate++) {
453 opp = dev_pm_opp_find_freq_ceil(dev: cpu_dev, freq: &rate);
454 if (IS_ERR(ptr: opp))
455 break;
456
457 dev_pm_opp_put(opp);
458 dev_pm_opp_disable(dev: cpu_dev, freq: rate);
459 }
460 } else {
461 dev_err(cpu_dev, "Invalid or empty opp table in device tree\n");
462 data->icc_dram_bw_scaling = false;
463 return ret;
464 }
465
466 freq_table = kcalloc((max_opps + 1), sizeof(*freq_table), GFP_KERNEL);
467 if (!freq_table)
468 return -ENOMEM;
469
470 /*
471 * Cross check the frequencies from BPMP-FW LUT against the OPP's present in DT.
472 * Enable only those DT OPP's which are present in LUT also.
473 */
474 cpufreq_for_each_valid_entry(pos, bpmp_lut) {
475 opp = dev_pm_opp_find_freq_exact(dev: cpu_dev, freq: pos->frequency * KHZ, available: false);
476 if (IS_ERR(ptr: opp))
477 continue;
478
479 dev_pm_opp_put(opp);
480
481 ret = dev_pm_opp_enable(dev: cpu_dev, freq: pos->frequency * KHZ);
482 if (ret < 0)
483 return ret;
484
485 freq_table[j].driver_data = pos->driver_data;
486 freq_table[j].frequency = pos->frequency;
487 j++;
488 }
489
490 freq_table[j].driver_data = pos->driver_data;
491 freq_table[j].frequency = CPUFREQ_TABLE_END;
492
493 *opp_table = &freq_table[0];
494
495 dev_pm_opp_set_sharing_cpus(cpu_dev, cpumask: policy->cpus);
496
497 return ret;
498}
499
500static int tegra194_cpufreq_init(struct cpufreq_policy *policy)
501{
502 struct tegra194_cpufreq_data *data = cpufreq_get_driver_data();
503 int maxcpus_per_cluster = data->soc->maxcpus_per_cluster;
504 u32 clusterid = data->cpu_data[policy->cpu].clusterid;
505 struct cpufreq_frequency_table *freq_table;
506 struct cpufreq_frequency_table *bpmp_lut;
507 u32 start_cpu, cpu;
508 int ret;
509
510 if (clusterid >= data->soc->num_clusters || !data->bpmp_luts[clusterid])
511 return -EINVAL;
512
513 start_cpu = rounddown(policy->cpu, maxcpus_per_cluster);
514 /* set same policy for all cpus in a cluster */
515 for (cpu = start_cpu; cpu < (start_cpu + maxcpus_per_cluster); cpu++) {
516 if (cpu_possible(cpu))
517 cpumask_set_cpu(cpu, dstp: policy->cpus);
518 }
519 policy->cpuinfo.transition_latency = TEGRA_CPUFREQ_TRANSITION_LATENCY;
520
521 bpmp_lut = data->bpmp_luts[clusterid];
522
523 if (data->icc_dram_bw_scaling) {
524 ret = tegra_cpufreq_init_cpufreq_table(policy, bpmp_lut, opp_table: &freq_table);
525 if (!ret) {
526 policy->freq_table = freq_table;
527 return 0;
528 }
529 }
530
531 data->icc_dram_bw_scaling = false;
532 policy->freq_table = bpmp_lut;
533 pr_info("OPP tables missing from DT, EMC frequency scaling disabled\n");
534
535 return 0;
536}
537
538static int tegra194_cpufreq_online(struct cpufreq_policy *policy)
539{
540 /* We did light-weight tear down earlier, nothing to do here */
541 return 0;
542}
543
544static int tegra194_cpufreq_offline(struct cpufreq_policy *policy)
545{
546 /*
547 * Preserve policy->driver_data and don't free resources on light-weight
548 * tear down.
549 */
550
551 return 0;
552}
553
554static void tegra194_cpufreq_exit(struct cpufreq_policy *policy)
555{
556 struct device *cpu_dev = get_cpu_device(cpu: policy->cpu);
557
558 dev_pm_opp_remove_all_dynamic(dev: cpu_dev);
559 dev_pm_opp_of_cpumask_remove_table(cpumask: policy->related_cpus);
560}
561
562static int tegra194_cpufreq_set_target(struct cpufreq_policy *policy,
563 unsigned int index)
564{
565 struct cpufreq_frequency_table *tbl = policy->freq_table + index;
566 struct tegra194_cpufreq_data *data = cpufreq_get_driver_data();
567
568 /*
569 * Each core writes frequency in per core register. Then both cores
570 * in a cluster run at same frequency which is the maximum frequency
571 * request out of the values requested by both cores in that cluster.
572 */
573 data->soc->ops->set_cpu_ndiv(policy, (u64)tbl->driver_data);
574
575 if (data->icc_dram_bw_scaling)
576 tegra_cpufreq_set_bw(policy, freq_khz: tbl->frequency);
577
578 return 0;
579}
580
581static struct cpufreq_driver tegra194_cpufreq_driver = {
582 .name = "tegra194",
583 .flags = CPUFREQ_CONST_LOOPS | CPUFREQ_NEED_INITIAL_FREQ_CHECK |
584 CPUFREQ_IS_COOLING_DEV,
585 .verify = cpufreq_generic_frequency_table_verify,
586 .target_index = tegra194_cpufreq_set_target,
587 .get = tegra194_get_speed,
588 .init = tegra194_cpufreq_init,
589 .exit = tegra194_cpufreq_exit,
590 .online = tegra194_cpufreq_online,
591 .offline = tegra194_cpufreq_offline,
592};
593
594static struct tegra_cpufreq_ops tegra194_cpufreq_ops = {
595 .read_counters = tegra194_read_counters,
596 .get_cpu_cluster_id = tegra194_get_cpu_cluster_id,
597 .get_cpu_ndiv = tegra194_get_cpu_ndiv,
598 .set_cpu_ndiv = tegra194_set_cpu_ndiv,
599};
600
601static const struct tegra_cpufreq_soc tegra194_cpufreq_soc = {
602 .ops = &tegra194_cpufreq_ops,
603 .maxcpus_per_cluster = 2,
604 .num_clusters = 4,
605 .refclk_delta_min = 16000,
606};
607
608static void tegra194_cpufreq_free_resources(void)
609{
610 destroy_workqueue(wq: read_counters_wq);
611}
612
613static struct cpufreq_frequency_table *
614tegra_cpufreq_bpmp_read_lut(struct platform_device *pdev, struct tegra_bpmp *bpmp,
615 unsigned int cluster_id)
616{
617 struct cpufreq_frequency_table *freq_table;
618 struct mrq_cpu_ndiv_limits_response resp;
619 unsigned int num_freqs, ndiv, delta_ndiv;
620 struct mrq_cpu_ndiv_limits_request req;
621 struct tegra_bpmp_message msg;
622 u16 freq_table_step_size;
623 int err, index;
624
625 memset(&req, 0, sizeof(req));
626 req.cluster_id = cluster_id;
627
628 memset(&msg, 0, sizeof(msg));
629 msg.mrq = MRQ_CPU_NDIV_LIMITS;
630 msg.tx.data = &req;
631 msg.tx.size = sizeof(req);
632 msg.rx.data = &resp;
633 msg.rx.size = sizeof(resp);
634
635 err = tegra_bpmp_transfer(bpmp, msg: &msg);
636 if (err)
637 return ERR_PTR(error: err);
638 if (msg.rx.ret == -BPMP_EINVAL) {
639 /* Cluster not available */
640 return NULL;
641 }
642 if (msg.rx.ret)
643 return ERR_PTR(error: -EINVAL);
644
645 /*
646 * Make sure frequency table step is a multiple of mdiv to match
647 * vhint table granularity.
648 */
649 freq_table_step_size = resp.mdiv *
650 DIV_ROUND_UP(CPUFREQ_TBL_STEP_HZ, resp.ref_clk_hz);
651
652 dev_dbg(&pdev->dev, "cluster %d: frequency table step size: %d\n",
653 cluster_id, freq_table_step_size);
654
655 delta_ndiv = resp.ndiv_max - resp.ndiv_min;
656
657 if (unlikely(delta_ndiv == 0)) {
658 num_freqs = 1;
659 } else {
660 /* We store both ndiv_min and ndiv_max hence the +1 */
661 num_freqs = delta_ndiv / freq_table_step_size + 1;
662 }
663
664 num_freqs += (delta_ndiv % freq_table_step_size) ? 1 : 0;
665
666 freq_table = devm_kcalloc(dev: &pdev->dev, n: num_freqs + 1,
667 size: sizeof(*freq_table), GFP_KERNEL);
668 if (!freq_table)
669 return ERR_PTR(error: -ENOMEM);
670
671 for (index = 0, ndiv = resp.ndiv_min;
672 ndiv < resp.ndiv_max;
673 index++, ndiv += freq_table_step_size) {
674 freq_table[index].driver_data = ndiv;
675 freq_table[index].frequency = map_ndiv_to_freq(nltbl: &resp, ndiv);
676 }
677
678 freq_table[index].driver_data = resp.ndiv_max;
679 freq_table[index++].frequency = map_ndiv_to_freq(nltbl: &resp, ndiv: resp.ndiv_max);
680 freq_table[index].frequency = CPUFREQ_TABLE_END;
681
682 return freq_table;
683}
684
685static int tegra194_cpufreq_store_physids(unsigned int cpu, struct tegra194_cpufreq_data *data)
686{
687 int num_cpus = data->soc->maxcpus_per_cluster * data->soc->num_clusters;
688 u32 cpuid, clusterid;
689 u64 mpidr_id;
690
691 if (cpu > (num_cpus - 1)) {
692 pr_err("cpufreq: wrong num of cpus or clusters in soc data\n");
693 return -EINVAL;
694 }
695
696 data->soc->ops->get_cpu_cluster_id(cpu, &cpuid, &clusterid);
697
698 mpidr_id = (clusterid * data->soc->maxcpus_per_cluster) + cpuid;
699
700 data->cpu_data[cpu].cpuid = cpuid;
701 data->cpu_data[cpu].clusterid = clusterid;
702 data->cpu_data[cpu].freq_core_reg = SCRATCH_FREQ_CORE_REG(data, mpidr_id);
703
704 return 0;
705}
706
707static int tegra194_cpufreq_probe(struct platform_device *pdev)
708{
709 const struct tegra_cpufreq_soc *soc;
710 struct tegra194_cpufreq_data *data;
711 struct tegra_bpmp *bpmp;
712 struct device *cpu_dev;
713 int err, i;
714 u32 cpu;
715
716 data = devm_kzalloc(dev: &pdev->dev, size: sizeof(*data), GFP_KERNEL);
717 if (!data)
718 return -ENOMEM;
719
720 soc = of_device_get_match_data(dev: &pdev->dev);
721
722 if (soc->ops && soc->maxcpus_per_cluster && soc->num_clusters && soc->refclk_delta_min) {
723 data->soc = soc;
724 } else {
725 dev_err(&pdev->dev, "soc data missing\n");
726 return -EINVAL;
727 }
728
729 data->bpmp_luts = devm_kcalloc(dev: &pdev->dev, n: data->soc->num_clusters,
730 size: sizeof(*data->bpmp_luts), GFP_KERNEL);
731 if (!data->bpmp_luts)
732 return -ENOMEM;
733
734 if (soc->actmon_cntr_base) {
735 /* mmio registers are used for frequency request and re-construction */
736 data->regs = devm_platform_ioremap_resource(pdev, index: 0);
737 if (IS_ERR(ptr: data->regs))
738 return PTR_ERR(ptr: data->regs);
739 }
740
741 data->cpu_data = devm_kcalloc(dev: &pdev->dev, n: data->soc->num_clusters *
742 data->soc->maxcpus_per_cluster,
743 size: sizeof(*data->cpu_data), GFP_KERNEL);
744 if (!data->cpu_data)
745 return -ENOMEM;
746
747 platform_set_drvdata(pdev, data);
748
749 bpmp = tegra_bpmp_get(dev: &pdev->dev);
750 if (IS_ERR(ptr: bpmp))
751 return PTR_ERR(ptr: bpmp);
752
753 read_counters_wq = alloc_workqueue("read_counters_wq",
754 __WQ_LEGACY | WQ_PERCPU, 1);
755 if (!read_counters_wq) {
756 dev_err(&pdev->dev, "fail to create_workqueue\n");
757 err = -EINVAL;
758 goto put_bpmp;
759 }
760
761 for (i = 0; i < data->soc->num_clusters; i++) {
762 data->bpmp_luts[i] = tegra_cpufreq_bpmp_read_lut(pdev, bpmp, cluster_id: i);
763 if (IS_ERR(ptr: data->bpmp_luts[i])) {
764 err = PTR_ERR(ptr: data->bpmp_luts[i]);
765 goto err_free_res;
766 }
767 }
768
769 for_each_possible_cpu(cpu) {
770 err = tegra194_cpufreq_store_physids(cpu, data);
771 if (err)
772 goto err_free_res;
773 }
774
775 tegra194_cpufreq_driver.driver_data = data;
776
777 /* Check for optional OPPv2 and interconnect paths on CPU0 to enable ICC scaling */
778 cpu_dev = get_cpu_device(cpu: 0);
779 if (!cpu_dev) {
780 err = -EPROBE_DEFER;
781 goto err_free_res;
782 }
783
784 if (dev_pm_opp_of_get_opp_desc_node(dev: cpu_dev)) {
785 err = dev_pm_opp_of_find_icc_paths(dev: cpu_dev, NULL);
786 if (!err)
787 data->icc_dram_bw_scaling = true;
788 }
789
790 err = cpufreq_register_driver(driver_data: &tegra194_cpufreq_driver);
791 if (!err)
792 goto put_bpmp;
793
794err_free_res:
795 tegra194_cpufreq_free_resources();
796put_bpmp:
797 tegra_bpmp_put(bpmp);
798 return err;
799}
800
801static void tegra194_cpufreq_remove(struct platform_device *pdev)
802{
803 cpufreq_unregister_driver(driver_data: &tegra194_cpufreq_driver);
804 tegra194_cpufreq_free_resources();
805}
806
807static const struct of_device_id tegra194_cpufreq_of_match[] = {
808 { .compatible = "nvidia,tegra194-ccplex", .data = &tegra194_cpufreq_soc },
809 { .compatible = "nvidia,tegra234-ccplex-cluster", .data = &tegra234_cpufreq_soc },
810 { .compatible = "nvidia,tegra239-ccplex-cluster", .data = &tegra239_cpufreq_soc },
811 { /* sentinel */ }
812};
813MODULE_DEVICE_TABLE(of, tegra194_cpufreq_of_match);
814
815static struct platform_driver tegra194_ccplex_driver = {
816 .driver = {
817 .name = "tegra194-cpufreq",
818 .of_match_table = tegra194_cpufreq_of_match,
819 },
820 .probe = tegra194_cpufreq_probe,
821 .remove = tegra194_cpufreq_remove,
822};
823module_platform_driver(tegra194_ccplex_driver);
824
825MODULE_AUTHOR("Mikko Perttunen <mperttunen@nvidia.com>");
826MODULE_AUTHOR("Sumit Gupta <sumitg@nvidia.com>");
827MODULE_DESCRIPTION("NVIDIA Tegra194 cpufreq driver");
828MODULE_LICENSE("GPL v2");
829

source code of linux/drivers/cpufreq/tegra194-cpufreq.c