xref: /linux/drivers/cpufreq/tegra194-cpufreq.c (revision 7f71507851fc7764b36a3221839607d3a45c2025)
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 
42 struct tegra_cpu_data {
43 	u32 cpuid;
44 	u32 clusterid;
45 	void __iomem *freq_core_reg;
46 };
47 
48 struct tegra_cpu_ctr {
49 	u32 cpu;
50 	u32 coreclk_cnt, last_coreclk_cnt;
51 	u32 refclk_cnt, last_refclk_cnt;
52 };
53 
54 struct read_counters_work {
55 	struct work_struct work;
56 	struct tegra_cpu_ctr c;
57 };
58 
59 struct 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 
66 struct 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 
74 struct 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 
82 static struct workqueue_struct *read_counters_wq;
83 
84 static 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(policy->cpu);
92 	if (!dev)
93 		return -ENODEV;
94 
95 	opp = dev_pm_opp_find_freq_exact(dev, freq_khz * KHZ, true);
96 	if (IS_ERR(opp))
97 		return PTR_ERR(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 
107 static void tegra_get_cpu_mpidr(void *mpidr)
108 {
109 	*((u64 *)mpidr) = read_cpuid_mpidr() & MPIDR_HWID_BITMASK;
110 }
111 
112 static void tegra234_get_cpu_cluster_id(u32 cpu, u32 *cpuid, u32 *clusterid)
113 {
114 	u64 mpidr;
115 
116 	smp_call_function_single(cpu, tegra_get_cpu_mpidr, &mpidr, true);
117 
118 	if (cpuid)
119 		*cpuid = MPIDR_AFFINITY_LEVEL(mpidr, 1);
120 	if (clusterid)
121 		*clusterid = MPIDR_AFFINITY_LEVEL(mpidr, 2);
122 }
123 
124 static 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(data->cpu_data[cpu].freq_core_reg) & NDIV_MASK;
129 
130 	return 0;
131 }
132 
133 static 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(ndiv, 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  */
149 static 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(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(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 
184 static 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 
191 static 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 
199 static 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 
207 static void tegra194_get_cpu_cluster_id(u32 cpu, u32 *cpuid, u32 *clusterid)
208 {
209 	u64 mpidr;
210 
211 	smp_call_function_single(cpu, tegra_get_cpu_mpidr, &mpidr, 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  */
228 static 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 
237 static 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 
243 static 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 
274 static 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  */
320 static 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, read_counters_wq, &read_counters_work.work);
335 	flush_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 
359 static 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 
368 static int tegra194_get_cpu_ndiv(u32 cpu, u32 cpuid, u32 clusterid, u64 *ndiv)
369 {
370 	return smp_call_function_single(cpu, tegra194_get_cpu_ndiv_sysreg, &ndiv, true);
371 }
372 
373 static 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 
380 static void tegra194_set_cpu_ndiv(struct cpufreq_policy *policy, u64 ndiv)
381 {
382 	on_each_cpu_mask(policy->cpus, tegra194_set_cpu_ndiv_sysreg, &ndiv, true);
383 }
384 
385 static 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 
423 static 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(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(cpu_dev, 0);
444 	if (!ret) {
445 		max_opps = dev_pm_opp_get_opp_count(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(cpu_dev, &rate);
454 			if (IS_ERR(opp))
455 				break;
456 
457 			dev_pm_opp_put(opp);
458 			dev_pm_opp_disable(cpu_dev, 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(cpu_dev, pos->frequency * KHZ, false);
476 		if (IS_ERR(opp))
477 			continue;
478 
479 		dev_pm_opp_put(opp);
480 
481 		ret = dev_pm_opp_enable(cpu_dev, 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, policy->cpus);
496 
497 	return ret;
498 }
499 
500 static 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, 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, &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 
538 static 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 
544 static 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 
554 static void tegra194_cpufreq_exit(struct cpufreq_policy *policy)
555 {
556 	struct device *cpu_dev = get_cpu_device(policy->cpu);
557 
558 	dev_pm_opp_remove_all_dynamic(cpu_dev);
559 	dev_pm_opp_of_cpumask_remove_table(policy->related_cpus);
560 }
561 
562 static 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, tbl->frequency);
577 
578 	return 0;
579 }
580 
581 static 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 	.attr = cpufreq_generic_attr,
593 };
594 
595 static struct tegra_cpufreq_ops tegra194_cpufreq_ops = {
596 	.read_counters = tegra194_read_counters,
597 	.get_cpu_cluster_id = tegra194_get_cpu_cluster_id,
598 	.get_cpu_ndiv = tegra194_get_cpu_ndiv,
599 	.set_cpu_ndiv = tegra194_set_cpu_ndiv,
600 };
601 
602 static const struct tegra_cpufreq_soc tegra194_cpufreq_soc = {
603 	.ops = &tegra194_cpufreq_ops,
604 	.maxcpus_per_cluster = 2,
605 	.num_clusters = 4,
606 	.refclk_delta_min = 16000,
607 };
608 
609 static void tegra194_cpufreq_free_resources(void)
610 {
611 	destroy_workqueue(read_counters_wq);
612 }
613 
614 static struct cpufreq_frequency_table *
615 tegra_cpufreq_bpmp_read_lut(struct platform_device *pdev, struct tegra_bpmp *bpmp,
616 			    unsigned int cluster_id)
617 {
618 	struct cpufreq_frequency_table *freq_table;
619 	struct mrq_cpu_ndiv_limits_response resp;
620 	unsigned int num_freqs, ndiv, delta_ndiv;
621 	struct mrq_cpu_ndiv_limits_request req;
622 	struct tegra_bpmp_message msg;
623 	u16 freq_table_step_size;
624 	int err, index;
625 
626 	memset(&req, 0, sizeof(req));
627 	req.cluster_id = cluster_id;
628 
629 	memset(&msg, 0, sizeof(msg));
630 	msg.mrq = MRQ_CPU_NDIV_LIMITS;
631 	msg.tx.data = &req;
632 	msg.tx.size = sizeof(req);
633 	msg.rx.data = &resp;
634 	msg.rx.size = sizeof(resp);
635 
636 	err = tegra_bpmp_transfer(bpmp, &msg);
637 	if (err)
638 		return ERR_PTR(err);
639 	if (msg.rx.ret == -BPMP_EINVAL) {
640 		/* Cluster not available */
641 		return NULL;
642 	}
643 	if (msg.rx.ret)
644 		return ERR_PTR(-EINVAL);
645 
646 	/*
647 	 * Make sure frequency table step is a multiple of mdiv to match
648 	 * vhint table granularity.
649 	 */
650 	freq_table_step_size = resp.mdiv *
651 			DIV_ROUND_UP(CPUFREQ_TBL_STEP_HZ, resp.ref_clk_hz);
652 
653 	dev_dbg(&pdev->dev, "cluster %d: frequency table step size: %d\n",
654 		cluster_id, freq_table_step_size);
655 
656 	delta_ndiv = resp.ndiv_max - resp.ndiv_min;
657 
658 	if (unlikely(delta_ndiv == 0)) {
659 		num_freqs = 1;
660 	} else {
661 		/* We store both ndiv_min and ndiv_max hence the +1 */
662 		num_freqs = delta_ndiv / freq_table_step_size + 1;
663 	}
664 
665 	num_freqs += (delta_ndiv % freq_table_step_size) ? 1 : 0;
666 
667 	freq_table = devm_kcalloc(&pdev->dev, num_freqs + 1,
668 				  sizeof(*freq_table), GFP_KERNEL);
669 	if (!freq_table)
670 		return ERR_PTR(-ENOMEM);
671 
672 	for (index = 0, ndiv = resp.ndiv_min;
673 			ndiv < resp.ndiv_max;
674 			index++, ndiv += freq_table_step_size) {
675 		freq_table[index].driver_data = ndiv;
676 		freq_table[index].frequency = map_ndiv_to_freq(&resp, ndiv);
677 	}
678 
679 	freq_table[index].driver_data = resp.ndiv_max;
680 	freq_table[index++].frequency = map_ndiv_to_freq(&resp, resp.ndiv_max);
681 	freq_table[index].frequency = CPUFREQ_TABLE_END;
682 
683 	return freq_table;
684 }
685 
686 static int tegra194_cpufreq_store_physids(unsigned int cpu, struct tegra194_cpufreq_data *data)
687 {
688 	int num_cpus = data->soc->maxcpus_per_cluster * data->soc->num_clusters;
689 	u32 cpuid, clusterid;
690 	u64 mpidr_id;
691 
692 	if (cpu > (num_cpus - 1)) {
693 		pr_err("cpufreq: wrong num of cpus or clusters in soc data\n");
694 		return -EINVAL;
695 	}
696 
697 	data->soc->ops->get_cpu_cluster_id(cpu, &cpuid, &clusterid);
698 
699 	mpidr_id = (clusterid * data->soc->maxcpus_per_cluster) + cpuid;
700 
701 	data->cpu_data[cpu].cpuid = cpuid;
702 	data->cpu_data[cpu].clusterid = clusterid;
703 	data->cpu_data[cpu].freq_core_reg = SCRATCH_FREQ_CORE_REG(data, mpidr_id);
704 
705 	return 0;
706 }
707 
708 static int tegra194_cpufreq_probe(struct platform_device *pdev)
709 {
710 	const struct tegra_cpufreq_soc *soc;
711 	struct tegra194_cpufreq_data *data;
712 	struct tegra_bpmp *bpmp;
713 	struct device *cpu_dev;
714 	int err, i;
715 	u32 cpu;
716 
717 	data = devm_kzalloc(&pdev->dev, sizeof(*data), GFP_KERNEL);
718 	if (!data)
719 		return -ENOMEM;
720 
721 	soc = of_device_get_match_data(&pdev->dev);
722 
723 	if (soc->ops && soc->maxcpus_per_cluster && soc->num_clusters && soc->refclk_delta_min) {
724 		data->soc = soc;
725 	} else {
726 		dev_err(&pdev->dev, "soc data missing\n");
727 		return -EINVAL;
728 	}
729 
730 	data->bpmp_luts = devm_kcalloc(&pdev->dev, data->soc->num_clusters,
731 				       sizeof(*data->bpmp_luts), GFP_KERNEL);
732 	if (!data->bpmp_luts)
733 		return -ENOMEM;
734 
735 	if (soc->actmon_cntr_base) {
736 		/* mmio registers are used for frequency request and re-construction */
737 		data->regs = devm_platform_ioremap_resource(pdev, 0);
738 		if (IS_ERR(data->regs))
739 			return PTR_ERR(data->regs);
740 	}
741 
742 	data->cpu_data = devm_kcalloc(&pdev->dev, data->soc->num_clusters *
743 				      data->soc->maxcpus_per_cluster,
744 				      sizeof(*data->cpu_data), GFP_KERNEL);
745 	if (!data->cpu_data)
746 		return -ENOMEM;
747 
748 	platform_set_drvdata(pdev, data);
749 
750 	bpmp = tegra_bpmp_get(&pdev->dev);
751 	if (IS_ERR(bpmp))
752 		return PTR_ERR(bpmp);
753 
754 	read_counters_wq = alloc_workqueue("read_counters_wq", __WQ_LEGACY, 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, i);
763 		if (IS_ERR(data->bpmp_luts[i])) {
764 			err = PTR_ERR(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(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(cpu_dev)) {
785 		err = dev_pm_opp_of_find_icc_paths(cpu_dev, NULL);
786 		if (!err)
787 			data->icc_dram_bw_scaling = true;
788 	}
789 
790 	err = cpufreq_register_driver(&tegra194_cpufreq_driver);
791 	if (!err)
792 		goto put_bpmp;
793 
794 err_free_res:
795 	tegra194_cpufreq_free_resources();
796 put_bpmp:
797 	tegra_bpmp_put(bpmp);
798 	return err;
799 }
800 
801 static void tegra194_cpufreq_remove(struct platform_device *pdev)
802 {
803 	cpufreq_unregister_driver(&tegra194_cpufreq_driver);
804 	tegra194_cpufreq_free_resources();
805 }
806 
807 static 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 };
813 MODULE_DEVICE_TABLE(of, tegra194_cpufreq_of_match);
814 
815 static 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 };
823 module_platform_driver(tegra194_ccplex_driver);
824 
825 MODULE_AUTHOR("Mikko Perttunen <mperttunen@nvidia.com>");
826 MODULE_AUTHOR("Sumit Gupta <sumitg@nvidia.com>");
827 MODULE_DESCRIPTION("NVIDIA Tegra194 cpufreq driver");
828 MODULE_LICENSE("GPL v2");
829