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  1// SPDX-License-Identifier: GPL-2.0-only
  2/*
  3 * Copyright (c) 2015 Linaro Ltd.
  4 * Author: Pi-Cheng Chen <pi-cheng.chen@linaro.org>
  5 */
  6
  7#include <linux/clk.h>
  8#include <linux/cpu.h>
  9#include <linux/cpufreq.h>
 10#include <linux/cpumask.h>
 11#include <linux/minmax.h>
 12#include <linux/module.h>
 13#include <linux/of.h>
 14#include <linux/of_platform.h>
 15#include <linux/platform_device.h>
 16#include <linux/pm_opp.h>
 17#include <linux/regulator/consumer.h>
 18
 19struct mtk_cpufreq_platform_data {
 20	int min_volt_shift;
 21	int max_volt_shift;
 22	int proc_max_volt;
 23	int sram_min_volt;
 24	int sram_max_volt;
 25	bool ccifreq_supported;
 26};
 27
 28/*
 29 * The struct mtk_cpu_dvfs_info holds necessary information for doing CPU DVFS
 30 * on each CPU power/clock domain of Mediatek SoCs. Each CPU cluster in
 31 * Mediatek SoCs has two voltage inputs, Vproc and Vsram. In some cases the two
 32 * voltage inputs need to be controlled under a hardware limitation:
 33 * 100mV < Vsram - Vproc < 200mV
 34 *
 35 * When scaling the clock frequency of a CPU clock domain, the clock source
 36 * needs to be switched to another stable PLL clock temporarily until
 37 * the original PLL becomes stable at target frequency.
 38 */
 39struct mtk_cpu_dvfs_info {
 40	struct cpumask cpus;
 41	struct device *cpu_dev;
 42	struct device *cci_dev;
 43	struct regulator *proc_reg;
 44	struct regulator *sram_reg;
 45	struct clk *cpu_clk;
 46	struct clk *inter_clk;
 47	struct list_head list_head;
 48	int intermediate_voltage;
 49	bool need_voltage_tracking;
 50	int vproc_on_boot;
 51	int pre_vproc;
 52	/* Avoid race condition for regulators between notify and policy */
 53	struct mutex reg_lock;
 54	struct notifier_block opp_nb;
 55	unsigned int opp_cpu;
 56	unsigned long current_freq;
 57	const struct mtk_cpufreq_platform_data *soc_data;
 58	int vtrack_max;
 59	bool ccifreq_bound;
 60};
 61
 62static struct platform_device *cpufreq_pdev;
 63
 64static LIST_HEAD(dvfs_info_list);
 65
 66static struct mtk_cpu_dvfs_info *mtk_cpu_dvfs_info_lookup(int cpu)
 67{
 68	struct mtk_cpu_dvfs_info *info;
 69
 70	list_for_each_entry(info, &dvfs_info_list, list_head) {
 71		if (cpumask_test_cpu(cpu, &info->cpus))
 72			return info;
 73	}
 74
 75	return NULL;
 76}
 77
 78static int mtk_cpufreq_voltage_tracking(struct mtk_cpu_dvfs_info *info,
 79					int new_vproc)
 80{
 81	const struct mtk_cpufreq_platform_data *soc_data = info->soc_data;
 82	struct regulator *proc_reg = info->proc_reg;
 83	struct regulator *sram_reg = info->sram_reg;
 84	int pre_vproc, pre_vsram, new_vsram, vsram, vproc, ret;
 85	int retry = info->vtrack_max;
 86
 87	pre_vproc = regulator_get_voltage(proc_reg);
 88	if (pre_vproc < 0) {
 89		dev_err(info->cpu_dev,
 90			"invalid Vproc value: %d\n", pre_vproc);
 91		return pre_vproc;
 92	}
 93
 94	pre_vsram = regulator_get_voltage(sram_reg);
 95	if (pre_vsram < 0) {
 96		dev_err(info->cpu_dev, "invalid Vsram value: %d\n", pre_vsram);
 97		return pre_vsram;
 98	}
 99
100	new_vsram = clamp(new_vproc + soc_data->min_volt_shift,
101			  soc_data->sram_min_volt, soc_data->sram_max_volt);
102
103	do {
104		if (pre_vproc <= new_vproc) {
105			vsram = clamp(pre_vproc + soc_data->max_volt_shift,
106				      soc_data->sram_min_volt, new_vsram);
107			ret = regulator_set_voltage(sram_reg, vsram,
108						    soc_data->sram_max_volt);
109
110			if (ret)
111				return ret;
112
113			if (vsram == soc_data->sram_max_volt ||
114			    new_vsram == soc_data->sram_min_volt)
115				vproc = new_vproc;
116			else
117				vproc = vsram - soc_data->min_volt_shift;
118
119			ret = regulator_set_voltage(proc_reg, vproc,
120						    soc_data->proc_max_volt);
121			if (ret) {
122				regulator_set_voltage(sram_reg, pre_vsram,
123						      soc_data->sram_max_volt);
124				return ret;
125			}
126		} else if (pre_vproc > new_vproc) {
127			vproc = max(new_vproc,
128				    pre_vsram - soc_data->max_volt_shift);
129			ret = regulator_set_voltage(proc_reg, vproc,
130						    soc_data->proc_max_volt);
131			if (ret)
132				return ret;
133
134			if (vproc == new_vproc)
135				vsram = new_vsram;
136			else
137				vsram = max(new_vsram,
138					    vproc + soc_data->min_volt_shift);
139
140			ret = regulator_set_voltage(sram_reg, vsram,
141						    soc_data->sram_max_volt);
142			if (ret) {
143				regulator_set_voltage(proc_reg, pre_vproc,
144						      soc_data->proc_max_volt);
145				return ret;
146			}
147		}
148
149		pre_vproc = vproc;
150		pre_vsram = vsram;
151
152		if (--retry < 0) {
153			dev_err(info->cpu_dev,
154				"over loop count, failed to set voltage\n");
155			return -EINVAL;
156		}
157	} while (vproc != new_vproc || vsram != new_vsram);
158
159	return 0;
160}
161
162static int mtk_cpufreq_set_voltage(struct mtk_cpu_dvfs_info *info, int vproc)
163{
164	const struct mtk_cpufreq_platform_data *soc_data = info->soc_data;
165	int ret;
166
167	if (info->need_voltage_tracking)
168		ret = mtk_cpufreq_voltage_tracking(info, vproc);
169	else
170		ret = regulator_set_voltage(info->proc_reg, vproc,
171					    soc_data->proc_max_volt);
172	if (!ret)
173		info->pre_vproc = vproc;
174
175	return ret;
176}
177
178static bool is_ccifreq_ready(struct mtk_cpu_dvfs_info *info)
179{
180	struct device_link *sup_link;
181
182	if (info->ccifreq_bound)
183		return true;
184
185	sup_link = device_link_add(info->cpu_dev, info->cci_dev,
186				   DL_FLAG_AUTOREMOVE_CONSUMER);
187	if (!sup_link) {
188		dev_err(info->cpu_dev, "cpu%d: sup_link is NULL\n", info->opp_cpu);
189		return false;
190	}
191
192	if (sup_link->supplier->links.status != DL_DEV_DRIVER_BOUND)
193		return false;
194
195	info->ccifreq_bound = true;
196
197	return true;
198}
199
200static int mtk_cpufreq_set_target(struct cpufreq_policy *policy,
201				  unsigned int index)
202{
203	struct cpufreq_frequency_table *freq_table = policy->freq_table;
204	struct clk *cpu_clk = policy->clk;
205	struct clk *armpll = clk_get_parent(cpu_clk);
206	struct mtk_cpu_dvfs_info *info = policy->driver_data;
207	struct device *cpu_dev = info->cpu_dev;
208	struct dev_pm_opp *opp;
209	long freq_hz, pre_freq_hz;
210	int vproc, pre_vproc, inter_vproc, target_vproc, ret;
211
212	inter_vproc = info->intermediate_voltage;
213
214	pre_freq_hz = clk_get_rate(cpu_clk);
215
216	mutex_lock(&info->reg_lock);
217
218	if (unlikely(info->pre_vproc <= 0))
219		pre_vproc = regulator_get_voltage(info->proc_reg);
220	else
221		pre_vproc = info->pre_vproc;
222
223	if (pre_vproc < 0) {
224		dev_err(cpu_dev, "invalid Vproc value: %d\n", pre_vproc);
225		ret = pre_vproc;
226		goto out;
227	}
228
229	freq_hz = freq_table[index].frequency * 1000;
230
231	opp = dev_pm_opp_find_freq_ceil(cpu_dev, &freq_hz);
232	if (IS_ERR(opp)) {
233		dev_err(cpu_dev, "cpu%d: failed to find OPP for %ld\n",
234			policy->cpu, freq_hz);
235		ret = PTR_ERR(opp);
236		goto out;
237	}
238	vproc = dev_pm_opp_get_voltage(opp);
239	dev_pm_opp_put(opp);
240
241	/*
242	 * If MediaTek cci is supported but is not ready, we will use the value
243	 * of max(target cpu voltage, booting voltage) to prevent high freqeuncy
244	 * low voltage crash.
245	 */
246	if (info->soc_data->ccifreq_supported && !is_ccifreq_ready(info))
247		vproc = max(vproc, info->vproc_on_boot);
248
249	/*
250	 * If the new voltage or the intermediate voltage is higher than the
251	 * current voltage, scale up voltage first.
252	 */
253	target_vproc = max(inter_vproc, vproc);
254	if (pre_vproc <= target_vproc) {
255		ret = mtk_cpufreq_set_voltage(info, target_vproc);
256		if (ret) {
257			dev_err(cpu_dev,
258				"cpu%d: failed to scale up voltage!\n", policy->cpu);
259			mtk_cpufreq_set_voltage(info, pre_vproc);
260			goto out;
261		}
262	}
263
264	/* Reparent the CPU clock to intermediate clock. */
265	ret = clk_set_parent(cpu_clk, info->inter_clk);
266	if (ret) {
267		dev_err(cpu_dev,
268			"cpu%d: failed to re-parent cpu clock!\n", policy->cpu);
269		mtk_cpufreq_set_voltage(info, pre_vproc);
270		goto out;
271	}
272
273	/* Set the original PLL to target rate. */
274	ret = clk_set_rate(armpll, freq_hz);
275	if (ret) {
276		dev_err(cpu_dev,
277			"cpu%d: failed to scale cpu clock rate!\n", policy->cpu);
278		clk_set_parent(cpu_clk, armpll);
279		mtk_cpufreq_set_voltage(info, pre_vproc);
280		goto out;
281	}
282
283	/* Set parent of CPU clock back to the original PLL. */
284	ret = clk_set_parent(cpu_clk, armpll);
285	if (ret) {
286		dev_err(cpu_dev,
287			"cpu%d: failed to re-parent cpu clock!\n", policy->cpu);
288		mtk_cpufreq_set_voltage(info, inter_vproc);
289		goto out;
290	}
291
292	/*
293	 * If the new voltage is lower than the intermediate voltage or the
294	 * original voltage, scale down to the new voltage.
295	 */
296	if (vproc < inter_vproc || vproc < pre_vproc) {
297		ret = mtk_cpufreq_set_voltage(info, vproc);
298		if (ret) {
299			dev_err(cpu_dev,
300				"cpu%d: failed to scale down voltage!\n", policy->cpu);
301			clk_set_parent(cpu_clk, info->inter_clk);
302			clk_set_rate(armpll, pre_freq_hz);
303			clk_set_parent(cpu_clk, armpll);
304			goto out;
305		}
306	}
307
308	info->current_freq = freq_hz;
309
310out:
311	mutex_unlock(&info->reg_lock);
312
313	return ret;
314}
315
316#define DYNAMIC_POWER "dynamic-power-coefficient"
317
318static int mtk_cpufreq_opp_notifier(struct notifier_block *nb,
319				    unsigned long event, void *data)
320{
321	struct dev_pm_opp *opp = data;
322	struct dev_pm_opp *new_opp;
323	struct mtk_cpu_dvfs_info *info;
324	unsigned long freq, volt;
325	struct cpufreq_policy *policy;
326	int ret = 0;
327
328	info = container_of(nb, struct mtk_cpu_dvfs_info, opp_nb);
329
330	if (event == OPP_EVENT_ADJUST_VOLTAGE) {
331		freq = dev_pm_opp_get_freq(opp);
332
333		mutex_lock(&info->reg_lock);
334		if (info->current_freq == freq) {
335			volt = dev_pm_opp_get_voltage(opp);
336			ret = mtk_cpufreq_set_voltage(info, volt);
337			if (ret)
338				dev_err(info->cpu_dev,
339					"failed to scale voltage: %d\n", ret);
340		}
341		mutex_unlock(&info->reg_lock);
342	} else if (event == OPP_EVENT_DISABLE) {
343		freq = dev_pm_opp_get_freq(opp);
344
345		/* case of current opp item is disabled */
346		if (info->current_freq == freq) {
347			freq = 1;
348			new_opp = dev_pm_opp_find_freq_ceil(info->cpu_dev,
349							    &freq);
350			if (IS_ERR(new_opp)) {
351				dev_err(info->cpu_dev,
352					"all opp items are disabled\n");
353				ret = PTR_ERR(new_opp);
354				return notifier_from_errno(ret);
355			}
356
357			dev_pm_opp_put(new_opp);
358			policy = cpufreq_cpu_get(info->opp_cpu);
359			if (policy) {
360				cpufreq_driver_target(policy, freq / 1000,
361						      CPUFREQ_RELATION_L);
362				cpufreq_cpu_put(policy);
363			}
364		}
365	}
366
367	return notifier_from_errno(ret);
368}
369
370static struct device *of_get_cci(struct device *cpu_dev)
371{
372	struct device_node *np;
373	struct platform_device *pdev;
374
375	np = of_parse_phandle(cpu_dev->of_node, "mediatek,cci", 0);
376	if (IS_ERR_OR_NULL(np))
377		return NULL;
378
379	pdev = of_find_device_by_node(np);
380	of_node_put(np);
381	if (IS_ERR_OR_NULL(pdev))
382		return NULL;
383
384	return &pdev->dev;
385}
386
387static int mtk_cpu_dvfs_info_init(struct mtk_cpu_dvfs_info *info, int cpu)
388{
389	struct device *cpu_dev;
390	struct dev_pm_opp *opp;
391	unsigned long rate;
392	int ret;
393
394	cpu_dev = get_cpu_device(cpu);
395	if (!cpu_dev) {
396		dev_err(cpu_dev, "failed to get cpu%d device\n", cpu);
397		return -ENODEV;
398	}
399	info->cpu_dev = cpu_dev;
400
401	info->ccifreq_bound = false;
402	if (info->soc_data->ccifreq_supported) {
403		info->cci_dev = of_get_cci(info->cpu_dev);
404		if (IS_ERR_OR_NULL(info->cci_dev)) {
405			ret = PTR_ERR(info->cci_dev);
406			dev_err(cpu_dev, "cpu%d: failed to get cci device\n", cpu);
407			return -ENODEV;
408		}
409	}
410
411	info->cpu_clk = clk_get(cpu_dev, "cpu");
412	if (IS_ERR(info->cpu_clk)) {
413		ret = PTR_ERR(info->cpu_clk);
414		return dev_err_probe(cpu_dev, ret,
415				     "cpu%d: failed to get cpu clk\n", cpu);
416	}
417
418	info->inter_clk = clk_get(cpu_dev, "intermediate");
419	if (IS_ERR(info->inter_clk)) {
420		ret = PTR_ERR(info->inter_clk);
421		dev_err_probe(cpu_dev, ret,
422			      "cpu%d: failed to get intermediate clk\n", cpu);
423		goto out_free_resources;
424	}
425
426	info->proc_reg = regulator_get_optional(cpu_dev, "proc");
427	if (IS_ERR(info->proc_reg)) {
428		ret = PTR_ERR(info->proc_reg);
429		dev_err_probe(cpu_dev, ret,
430			      "cpu%d: failed to get proc regulator\n", cpu);
431		goto out_free_resources;
432	}
433
434	ret = regulator_enable(info->proc_reg);
435	if (ret) {
436		dev_warn(cpu_dev, "cpu%d: failed to enable vproc\n", cpu);
437		goto out_free_resources;
438	}
439
440	/* Both presence and absence of sram regulator are valid cases. */
441	info->sram_reg = regulator_get_optional(cpu_dev, "sram");
442	if (IS_ERR(info->sram_reg)) {
443		ret = PTR_ERR(info->sram_reg);
444		if (ret == -EPROBE_DEFER)
445			goto out_free_resources;
446
447		info->sram_reg = NULL;
448	} else {
449		ret = regulator_enable(info->sram_reg);
450		if (ret) {
451			dev_warn(cpu_dev, "cpu%d: failed to enable vsram\n", cpu);
452			goto out_free_resources;
453		}
454	}
455
456	/* Get OPP-sharing information from "operating-points-v2" bindings */
457	ret = dev_pm_opp_of_get_sharing_cpus(cpu_dev, &info->cpus);
458	if (ret) {
459		dev_err(cpu_dev,
460			"cpu%d: failed to get OPP-sharing information\n", cpu);
461		goto out_free_resources;
462	}
463
464	ret = dev_pm_opp_of_cpumask_add_table(&info->cpus);
465	if (ret) {
466		dev_warn(cpu_dev, "cpu%d: no OPP table\n", cpu);
467		goto out_free_resources;
468	}
469
470	ret = clk_prepare_enable(info->cpu_clk);
471	if (ret)
472		goto out_free_opp_table;
473
474	ret = clk_prepare_enable(info->inter_clk);
475	if (ret)
476		goto out_disable_mux_clock;
477
478	if (info->soc_data->ccifreq_supported) {
479		info->vproc_on_boot = regulator_get_voltage(info->proc_reg);
480		if (info->vproc_on_boot < 0) {
481			ret = info->vproc_on_boot;
482			dev_err(info->cpu_dev,
483				"invalid Vproc value: %d\n", info->vproc_on_boot);
484			goto out_disable_inter_clock;
485		}
486	}
487
488	/* Search a safe voltage for intermediate frequency. */
489	rate = clk_get_rate(info->inter_clk);
490	opp = dev_pm_opp_find_freq_ceil(cpu_dev, &rate);
491	if (IS_ERR(opp)) {
492		dev_err(cpu_dev, "cpu%d: failed to get intermediate opp\n", cpu);
493		ret = PTR_ERR(opp);
494		goto out_disable_inter_clock;
495	}
496	info->intermediate_voltage = dev_pm_opp_get_voltage(opp);
497	dev_pm_opp_put(opp);
498
499	mutex_init(&info->reg_lock);
500	info->current_freq = clk_get_rate(info->cpu_clk);
501
502	info->opp_cpu = cpu;
503	info->opp_nb.notifier_call = mtk_cpufreq_opp_notifier;
504	ret = dev_pm_opp_register_notifier(cpu_dev, &info->opp_nb);
505	if (ret) {
506		dev_err(cpu_dev, "cpu%d: failed to register opp notifier\n", cpu);
507		goto out_disable_inter_clock;
508	}
509
510	/*
511	 * If SRAM regulator is present, software "voltage tracking" is needed
512	 * for this CPU power domain.
513	 */
514	info->need_voltage_tracking = (info->sram_reg != NULL);
515
516	/*
517	 * We assume min voltage is 0 and tracking target voltage using
518	 * min_volt_shift for each iteration.
519	 * The vtrack_max is 3 times of expeted iteration count.
520	 */
521	info->vtrack_max = 3 * DIV_ROUND_UP(max(info->soc_data->sram_max_volt,
522						info->soc_data->proc_max_volt),
523					    info->soc_data->min_volt_shift);
524
525	return 0;
526
527out_disable_inter_clock:
528	clk_disable_unprepare(info->inter_clk);
529
530out_disable_mux_clock:
531	clk_disable_unprepare(info->cpu_clk);
532
533out_free_opp_table:
534	dev_pm_opp_of_cpumask_remove_table(&info->cpus);
535
536out_free_resources:
537	if (regulator_is_enabled(info->proc_reg))
538		regulator_disable(info->proc_reg);
539	if (info->sram_reg && regulator_is_enabled(info->sram_reg))
540		regulator_disable(info->sram_reg);
541
542	if (!IS_ERR(info->proc_reg))
543		regulator_put(info->proc_reg);
544	if (!IS_ERR(info->sram_reg))
545		regulator_put(info->sram_reg);
546	if (!IS_ERR(info->cpu_clk))
547		clk_put(info->cpu_clk);
548	if (!IS_ERR(info->inter_clk))
549		clk_put(info->inter_clk);
550
551	return ret;
552}
553
554static void mtk_cpu_dvfs_info_release(struct mtk_cpu_dvfs_info *info)
555{
556	if (!IS_ERR(info->proc_reg)) {
557		regulator_disable(info->proc_reg);
558		regulator_put(info->proc_reg);
559	}
560	if (!IS_ERR(info->sram_reg)) {
561		regulator_disable(info->sram_reg);
562		regulator_put(info->sram_reg);
563	}
564	if (!IS_ERR(info->cpu_clk)) {
565		clk_disable_unprepare(info->cpu_clk);
566		clk_put(info->cpu_clk);
567	}
568	if (!IS_ERR(info->inter_clk)) {
569		clk_disable_unprepare(info->inter_clk);
570		clk_put(info->inter_clk);
571	}
572
573	dev_pm_opp_of_cpumask_remove_table(&info->cpus);
574	dev_pm_opp_unregister_notifier(info->cpu_dev, &info->opp_nb);
575}
576
577static int mtk_cpufreq_init(struct cpufreq_policy *policy)
578{
579	struct mtk_cpu_dvfs_info *info;
580	struct cpufreq_frequency_table *freq_table;
581	int ret;
582
583	info = mtk_cpu_dvfs_info_lookup(policy->cpu);
584	if (!info) {
585		pr_err("dvfs info for cpu%d is not initialized.\n",
586			policy->cpu);
587		return -EINVAL;
588	}
589
590	ret = dev_pm_opp_init_cpufreq_table(info->cpu_dev, &freq_table);
591	if (ret) {
592		dev_err(info->cpu_dev,
593			"failed to init cpufreq table for cpu%d: %d\n",
594			policy->cpu, ret);
595		return ret;
596	}
597
598	cpumask_copy(policy->cpus, &info->cpus);
599	policy->freq_table = freq_table;
600	policy->driver_data = info;
601	policy->clk = info->cpu_clk;
602
603	return 0;
604}
605
606static int mtk_cpufreq_exit(struct cpufreq_policy *policy)
607{
608	struct mtk_cpu_dvfs_info *info = policy->driver_data;
609
610	dev_pm_opp_free_cpufreq_table(info->cpu_dev, &policy->freq_table);
611
612	return 0;
613}
614
615static struct cpufreq_driver mtk_cpufreq_driver = {
616	.flags = CPUFREQ_NEED_INITIAL_FREQ_CHECK |
617		 CPUFREQ_HAVE_GOVERNOR_PER_POLICY |
618		 CPUFREQ_IS_COOLING_DEV,
619	.verify = cpufreq_generic_frequency_table_verify,
620	.target_index = mtk_cpufreq_set_target,
621	.get = cpufreq_generic_get,
622	.init = mtk_cpufreq_init,
623	.exit = mtk_cpufreq_exit,
624	.register_em = cpufreq_register_em_with_opp,
625	.name = "mtk-cpufreq",
626	.attr = cpufreq_generic_attr,
627};
628
629static int mtk_cpufreq_probe(struct platform_device *pdev)
630{
631	const struct mtk_cpufreq_platform_data *data;
632	struct mtk_cpu_dvfs_info *info, *tmp;
633	int cpu, ret;
634
635	data = dev_get_platdata(&pdev->dev);
636	if (!data) {
637		dev_err(&pdev->dev,
638			"failed to get mtk cpufreq platform data\n");
639		return -ENODEV;
640	}
641
642	for_each_possible_cpu(cpu) {
643		info = mtk_cpu_dvfs_info_lookup(cpu);
644		if (info)
645			continue;
646
647		info = devm_kzalloc(&pdev->dev, sizeof(*info), GFP_KERNEL);
648		if (!info) {
649			ret = -ENOMEM;
650			goto release_dvfs_info_list;
651		}
652
653		info->soc_data = data;
654		ret = mtk_cpu_dvfs_info_init(info, cpu);
655		if (ret) {
656			dev_err(&pdev->dev,
657				"failed to initialize dvfs info for cpu%d\n",
658				cpu);
659			goto release_dvfs_info_list;
660		}
661
662		list_add(&info->list_head, &dvfs_info_list);
663	}
664
665	ret = cpufreq_register_driver(&mtk_cpufreq_driver);
666	if (ret) {
667		dev_err(&pdev->dev, "failed to register mtk cpufreq driver\n");
668		goto release_dvfs_info_list;
669	}
670
671	return 0;
672
673release_dvfs_info_list:
674	list_for_each_entry_safe(info, tmp, &dvfs_info_list, list_head) {
675		mtk_cpu_dvfs_info_release(info);
676		list_del(&info->list_head);
677	}
678
679	return ret;
680}
681
682static struct platform_driver mtk_cpufreq_platdrv = {
683	.driver = {
684		.name	= "mtk-cpufreq",
685	},
686	.probe		= mtk_cpufreq_probe,
687};
688
689static const struct mtk_cpufreq_platform_data mt2701_platform_data = {
690	.min_volt_shift = 100000,
691	.max_volt_shift = 200000,
692	.proc_max_volt = 1150000,
693	.sram_min_volt = 0,
694	.sram_max_volt = 1150000,
695	.ccifreq_supported = false,
696};
697
698static const struct mtk_cpufreq_platform_data mt8183_platform_data = {
699	.min_volt_shift = 100000,
700	.max_volt_shift = 200000,
701	.proc_max_volt = 1150000,
702	.sram_min_volt = 0,
703	.sram_max_volt = 1150000,
704	.ccifreq_supported = true,
705};
706
707static const struct mtk_cpufreq_platform_data mt8186_platform_data = {
708	.min_volt_shift = 100000,
709	.max_volt_shift = 250000,
710	.proc_max_volt = 1118750,
711	.sram_min_volt = 850000,
712	.sram_max_volt = 1118750,
713	.ccifreq_supported = true,
714};
715
716/* List of machines supported by this driver */
717static const struct of_device_id mtk_cpufreq_machines[] __initconst = {
718	{ .compatible = "mediatek,mt2701", .data = &mt2701_platform_data },
719	{ .compatible = "mediatek,mt2712", .data = &mt2701_platform_data },
720	{ .compatible = "mediatek,mt7622", .data = &mt2701_platform_data },
721	{ .compatible = "mediatek,mt7623", .data = &mt2701_platform_data },
722	{ .compatible = "mediatek,mt8167", .data = &mt2701_platform_data },
723	{ .compatible = "mediatek,mt817x", .data = &mt2701_platform_data },
724	{ .compatible = "mediatek,mt8173", .data = &mt2701_platform_data },
725	{ .compatible = "mediatek,mt8176", .data = &mt2701_platform_data },
726	{ .compatible = "mediatek,mt8183", .data = &mt8183_platform_data },
727	{ .compatible = "mediatek,mt8186", .data = &mt8186_platform_data },
728	{ .compatible = "mediatek,mt8365", .data = &mt2701_platform_data },
729	{ .compatible = "mediatek,mt8516", .data = &mt2701_platform_data },
730	{ }
731};
732MODULE_DEVICE_TABLE(of, mtk_cpufreq_machines);
733
734static int __init mtk_cpufreq_driver_init(void)
735{
736	struct device_node *np;
737	const struct of_device_id *match;
738	const struct mtk_cpufreq_platform_data *data;
739	int err;
740
741	np = of_find_node_by_path("/");
742	if (!np)
743		return -ENODEV;
744
745	match = of_match_node(mtk_cpufreq_machines, np);
746	of_node_put(np);
747	if (!match) {
748		pr_debug("Machine is not compatible with mtk-cpufreq\n");
749		return -ENODEV;
750	}
751	data = match->data;
752
753	err = platform_driver_register(&mtk_cpufreq_platdrv);
754	if (err)
755		return err;
756
757	/*
758	 * Since there's no place to hold device registration code and no
759	 * device tree based way to match cpufreq driver yet, both the driver
760	 * and the device registration codes are put here to handle defer
761	 * probing.
762	 */
763	cpufreq_pdev = platform_device_register_data(NULL, "mtk-cpufreq", -1,
764						     data, sizeof(*data));
765	if (IS_ERR(cpufreq_pdev)) {
766		pr_err("failed to register mtk-cpufreq platform device\n");
767		platform_driver_unregister(&mtk_cpufreq_platdrv);
768		return PTR_ERR(cpufreq_pdev);
769	}
770
771	return 0;
772}
773module_init(mtk_cpufreq_driver_init)
774
775static void __exit mtk_cpufreq_driver_exit(void)
776{
777	platform_device_unregister(cpufreq_pdev);
778	platform_driver_unregister(&mtk_cpufreq_platdrv);
779}
780module_exit(mtk_cpufreq_driver_exit)
781
782MODULE_DESCRIPTION("MediaTek CPUFreq driver");
783MODULE_AUTHOR("Pi-Cheng Chen <pi-cheng.chen@linaro.org>");
784MODULE_LICENSE("GPL v2");