xref: /linux-5.15/drivers/cpufreq/s3c24xx-cpufreq.c (revision f2006e27396f55276f24434f56e208d86e7f9908)
1 /*
2  * Copyright (c) 2006-2008 Simtec Electronics
3  *	http://armlinux.simtec.co.uk/
4  *	Ben Dooks <ben@simtec.co.uk>
5  *
6  * S3C24XX CPU Frequency scaling
7  *
8  * This program is free software; you can redistribute it and/or modify
9  * it under the terms of the GNU General Public License version 2 as
10  * published by the Free Software Foundation.
11 */
12 
13 #include <linux/init.h>
14 #include <linux/module.h>
15 #include <linux/interrupt.h>
16 #include <linux/ioport.h>
17 #include <linux/cpufreq.h>
18 #include <linux/cpu.h>
19 #include <linux/clk.h>
20 #include <linux/err.h>
21 #include <linux/io.h>
22 #include <linux/device.h>
23 #include <linux/sysfs.h>
24 #include <linux/slab.h>
25 
26 #include <asm/mach/arch.h>
27 #include <asm/mach/map.h>
28 
29 #include <plat/cpu.h>
30 #include <plat/clock.h>
31 #include <plat/cpu-freq-core.h>
32 
33 #include <mach/regs-clock.h>
34 
35 /* note, cpufreq support deals in kHz, no Hz */
36 
37 static struct cpufreq_driver s3c24xx_driver;
38 static struct s3c_cpufreq_config cpu_cur;
39 static struct s3c_iotimings s3c24xx_iotiming;
40 static struct cpufreq_frequency_table *pll_reg;
41 static unsigned int last_target = ~0;
42 static unsigned int ftab_size;
43 static struct cpufreq_frequency_table *ftab;
44 
45 static struct clk *_clk_mpll;
46 static struct clk *_clk_xtal;
47 static struct clk *clk_fclk;
48 static struct clk *clk_hclk;
49 static struct clk *clk_pclk;
50 static struct clk *clk_arm;
51 
52 #ifdef CONFIG_CPU_FREQ_S3C24XX_DEBUGFS
53 struct s3c_cpufreq_config *s3c_cpufreq_getconfig(void)
54 {
55 	return &cpu_cur;
56 }
57 
58 struct s3c_iotimings *s3c_cpufreq_getiotimings(void)
59 {
60 	return &s3c24xx_iotiming;
61 }
62 #endif /* CONFIG_CPU_FREQ_S3C24XX_DEBUGFS */
63 
64 static void s3c_cpufreq_getcur(struct s3c_cpufreq_config *cfg)
65 {
66 	unsigned long fclk, pclk, hclk, armclk;
67 
68 	cfg->freq.fclk = fclk = clk_get_rate(clk_fclk);
69 	cfg->freq.hclk = hclk = clk_get_rate(clk_hclk);
70 	cfg->freq.pclk = pclk = clk_get_rate(clk_pclk);
71 	cfg->freq.armclk = armclk = clk_get_rate(clk_arm);
72 
73 	cfg->pll.driver_data = __raw_readl(S3C2410_MPLLCON);
74 	cfg->pll.frequency = fclk;
75 
76 	cfg->freq.hclk_tns = 1000000000 / (cfg->freq.hclk / 10);
77 
78 	cfg->divs.h_divisor = fclk / hclk;
79 	cfg->divs.p_divisor = fclk / pclk;
80 }
81 
82 static inline void s3c_cpufreq_calc(struct s3c_cpufreq_config *cfg)
83 {
84 	unsigned long pll = cfg->pll.frequency;
85 
86 	cfg->freq.fclk = pll;
87 	cfg->freq.hclk = pll / cfg->divs.h_divisor;
88 	cfg->freq.pclk = pll / cfg->divs.p_divisor;
89 
90 	/* convert hclk into 10ths of nanoseconds for io calcs */
91 	cfg->freq.hclk_tns = 1000000000 / (cfg->freq.hclk / 10);
92 }
93 
94 static inline int closer(unsigned int target, unsigned int n, unsigned int c)
95 {
96 	int diff_cur = abs(target - c);
97 	int diff_new = abs(target - n);
98 
99 	return (diff_new < diff_cur);
100 }
101 
102 static void s3c_cpufreq_show(const char *pfx,
103 				 struct s3c_cpufreq_config *cfg)
104 {
105 	s3c_freq_dbg("%s: Fvco=%u, F=%lu, A=%lu, H=%lu (%u), P=%lu (%u)\n",
106 		     pfx, cfg->pll.frequency, cfg->freq.fclk, cfg->freq.armclk,
107 		     cfg->freq.hclk, cfg->divs.h_divisor,
108 		     cfg->freq.pclk, cfg->divs.p_divisor);
109 }
110 
111 /* functions to wrapper the driver info calls to do the cpu specific work */
112 
113 static void s3c_cpufreq_setio(struct s3c_cpufreq_config *cfg)
114 {
115 	if (cfg->info->set_iotiming)
116 		(cfg->info->set_iotiming)(cfg, &s3c24xx_iotiming);
117 }
118 
119 static int s3c_cpufreq_calcio(struct s3c_cpufreq_config *cfg)
120 {
121 	if (cfg->info->calc_iotiming)
122 		return (cfg->info->calc_iotiming)(cfg, &s3c24xx_iotiming);
123 
124 	return 0;
125 }
126 
127 static void s3c_cpufreq_setrefresh(struct s3c_cpufreq_config *cfg)
128 {
129 	(cfg->info->set_refresh)(cfg);
130 }
131 
132 static void s3c_cpufreq_setdivs(struct s3c_cpufreq_config *cfg)
133 {
134 	(cfg->info->set_divs)(cfg);
135 }
136 
137 static int s3c_cpufreq_calcdivs(struct s3c_cpufreq_config *cfg)
138 {
139 	return (cfg->info->calc_divs)(cfg);
140 }
141 
142 static void s3c_cpufreq_setfvco(struct s3c_cpufreq_config *cfg)
143 {
144 	(cfg->info->set_fvco)(cfg);
145 }
146 
147 static inline void s3c_cpufreq_resume_clocks(void)
148 {
149 	cpu_cur.info->resume_clocks();
150 }
151 
152 static inline void s3c_cpufreq_updateclk(struct clk *clk,
153 					 unsigned int freq)
154 {
155 	clk_set_rate(clk, freq);
156 }
157 
158 static int s3c_cpufreq_settarget(struct cpufreq_policy *policy,
159 				 unsigned int target_freq,
160 				 struct cpufreq_frequency_table *pll)
161 {
162 	struct s3c_cpufreq_freqs freqs;
163 	struct s3c_cpufreq_config cpu_new;
164 	unsigned long flags;
165 
166 	cpu_new = cpu_cur;  /* copy new from current */
167 
168 	s3c_cpufreq_show("cur", &cpu_cur);
169 
170 	/* TODO - check for DMA currently outstanding */
171 
172 	cpu_new.pll = pll ? *pll : cpu_cur.pll;
173 
174 	if (pll)
175 		freqs.pll_changing = 1;
176 
177 	/* update our frequencies */
178 
179 	cpu_new.freq.armclk = target_freq;
180 	cpu_new.freq.fclk = cpu_new.pll.frequency;
181 
182 	if (s3c_cpufreq_calcdivs(&cpu_new) < 0) {
183 		printk(KERN_ERR "no divisors for %d\n", target_freq);
184 		goto err_notpossible;
185 	}
186 
187 	s3c_freq_dbg("%s: got divs\n", __func__);
188 
189 	s3c_cpufreq_calc(&cpu_new);
190 
191 	s3c_freq_dbg("%s: calculated frequencies for new\n", __func__);
192 
193 	if (cpu_new.freq.hclk != cpu_cur.freq.hclk) {
194 		if (s3c_cpufreq_calcio(&cpu_new) < 0) {
195 			printk(KERN_ERR "%s: no IO timings\n", __func__);
196 			goto err_notpossible;
197 		}
198 	}
199 
200 	s3c_cpufreq_show("new", &cpu_new);
201 
202 	/* setup our cpufreq parameters */
203 
204 	freqs.old = cpu_cur.freq;
205 	freqs.new = cpu_new.freq;
206 
207 	freqs.freqs.old = cpu_cur.freq.armclk / 1000;
208 	freqs.freqs.new = cpu_new.freq.armclk / 1000;
209 
210 	/* update f/h/p clock settings before we issue the change
211 	 * notification, so that drivers do not need to do anything
212 	 * special if they want to recalculate on CPUFREQ_PRECHANGE. */
213 
214 	s3c_cpufreq_updateclk(_clk_mpll, cpu_new.pll.frequency);
215 	s3c_cpufreq_updateclk(clk_fclk, cpu_new.freq.fclk);
216 	s3c_cpufreq_updateclk(clk_hclk, cpu_new.freq.hclk);
217 	s3c_cpufreq_updateclk(clk_pclk, cpu_new.freq.pclk);
218 
219 	/* start the frequency change */
220 	cpufreq_notify_transition(policy, &freqs.freqs, CPUFREQ_PRECHANGE);
221 
222 	/* If hclk is staying the same, then we do not need to
223 	 * re-write the IO or the refresh timings whilst we are changing
224 	 * speed. */
225 
226 	local_irq_save(flags);
227 
228 	/* is our memory clock slowing down? */
229 	if (cpu_new.freq.hclk < cpu_cur.freq.hclk) {
230 		s3c_cpufreq_setrefresh(&cpu_new);
231 		s3c_cpufreq_setio(&cpu_new);
232 	}
233 
234 	if (cpu_new.freq.fclk == cpu_cur.freq.fclk) {
235 		/* not changing PLL, just set the divisors */
236 
237 		s3c_cpufreq_setdivs(&cpu_new);
238 	} else {
239 		if (cpu_new.freq.fclk < cpu_cur.freq.fclk) {
240 			/* slow the cpu down, then set divisors */
241 
242 			s3c_cpufreq_setfvco(&cpu_new);
243 			s3c_cpufreq_setdivs(&cpu_new);
244 		} else {
245 			/* set the divisors, then speed up */
246 
247 			s3c_cpufreq_setdivs(&cpu_new);
248 			s3c_cpufreq_setfvco(&cpu_new);
249 		}
250 	}
251 
252 	/* did our memory clock speed up */
253 	if (cpu_new.freq.hclk > cpu_cur.freq.hclk) {
254 		s3c_cpufreq_setrefresh(&cpu_new);
255 		s3c_cpufreq_setio(&cpu_new);
256 	}
257 
258 	/* update our current settings */
259 	cpu_cur = cpu_new;
260 
261 	local_irq_restore(flags);
262 
263 	/* notify everyone we've done this */
264 	cpufreq_notify_transition(policy, &freqs.freqs, CPUFREQ_POSTCHANGE);
265 
266 	s3c_freq_dbg("%s: finished\n", __func__);
267 	return 0;
268 
269  err_notpossible:
270 	printk(KERN_ERR "no compatible settings for %d\n", target_freq);
271 	return -EINVAL;
272 }
273 
274 /* s3c_cpufreq_target
275  *
276  * called by the cpufreq core to adjust the frequency that the CPU
277  * is currently running at.
278  */
279 
280 static int s3c_cpufreq_target(struct cpufreq_policy *policy,
281 			      unsigned int target_freq,
282 			      unsigned int relation)
283 {
284 	struct cpufreq_frequency_table *pll;
285 	unsigned int index;
286 
287 	/* avoid repeated calls which cause a needless amout of duplicated
288 	 * logging output (and CPU time as the calculation process is
289 	 * done) */
290 	if (target_freq == last_target)
291 		return 0;
292 
293 	last_target = target_freq;
294 
295 	s3c_freq_dbg("%s: policy %p, target %u, relation %u\n",
296 		     __func__, policy, target_freq, relation);
297 
298 	if (ftab) {
299 		if (cpufreq_frequency_table_target(policy, ftab,
300 						   target_freq, relation,
301 						   &index)) {
302 			s3c_freq_dbg("%s: table failed\n", __func__);
303 			return -EINVAL;
304 		}
305 
306 		s3c_freq_dbg("%s: adjust %d to entry %d (%u)\n", __func__,
307 			     target_freq, index, ftab[index].frequency);
308 		target_freq = ftab[index].frequency;
309 	}
310 
311 	target_freq *= 1000;  /* convert target to Hz */
312 
313 	/* find the settings for our new frequency */
314 
315 	if (!pll_reg || cpu_cur.lock_pll) {
316 		/* either we've not got any PLL values, or we've locked
317 		 * to the current one. */
318 		pll = NULL;
319 	} else {
320 		struct cpufreq_policy tmp_policy;
321 		int ret;
322 
323 		/* we keep the cpu pll table in Hz, to ensure we get an
324 		 * accurate value for the PLL output. */
325 
326 		tmp_policy.min = policy->min * 1000;
327 		tmp_policy.max = policy->max * 1000;
328 		tmp_policy.cpu = policy->cpu;
329 
330 		/* cpufreq_frequency_table_target uses a pointer to 'index'
331 		 * which is the number of the table entry, not the value of
332 		 * the table entry's index field. */
333 
334 		ret = cpufreq_frequency_table_target(&tmp_policy, pll_reg,
335 						     target_freq, relation,
336 						     &index);
337 
338 		if (ret < 0) {
339 			printk(KERN_ERR "%s: no PLL available\n", __func__);
340 			goto err_notpossible;
341 		}
342 
343 		pll = pll_reg + index;
344 
345 		s3c_freq_dbg("%s: target %u => %u\n",
346 			     __func__, target_freq, pll->frequency);
347 
348 		target_freq = pll->frequency;
349 	}
350 
351 	return s3c_cpufreq_settarget(policy, target_freq, pll);
352 
353  err_notpossible:
354 	printk(KERN_ERR "no compatible settings for %d\n", target_freq);
355 	return -EINVAL;
356 }
357 
358 static unsigned int s3c_cpufreq_get(unsigned int cpu)
359 {
360 	return clk_get_rate(clk_arm) / 1000;
361 }
362 
363 struct clk *s3c_cpufreq_clk_get(struct device *dev, const char *name)
364 {
365 	struct clk *clk;
366 
367 	clk = clk_get(dev, name);
368 	if (IS_ERR(clk))
369 		printk(KERN_ERR "cpufreq: failed to get clock '%s'\n", name);
370 
371 	return clk;
372 }
373 
374 static int s3c_cpufreq_init(struct cpufreq_policy *policy)
375 {
376 	printk(KERN_INFO "%s: initialising policy %p\n", __func__, policy);
377 
378 	if (policy->cpu != 0)
379 		return -EINVAL;
380 
381 	policy->cur = s3c_cpufreq_get(0);
382 	policy->min = policy->cpuinfo.min_freq = 0;
383 	policy->max = policy->cpuinfo.max_freq = cpu_cur.info->max.fclk / 1000;
384 	policy->governor = CPUFREQ_DEFAULT_GOVERNOR;
385 
386 	/* feed the latency information from the cpu driver */
387 	policy->cpuinfo.transition_latency = cpu_cur.info->latency;
388 
389 	if (ftab)
390 		cpufreq_frequency_table_cpuinfo(policy, ftab);
391 
392 	return 0;
393 }
394 
395 static __init int s3c_cpufreq_initclks(void)
396 {
397 	_clk_mpll = s3c_cpufreq_clk_get(NULL, "mpll");
398 	_clk_xtal = s3c_cpufreq_clk_get(NULL, "xtal");
399 	clk_fclk = s3c_cpufreq_clk_get(NULL, "fclk");
400 	clk_hclk = s3c_cpufreq_clk_get(NULL, "hclk");
401 	clk_pclk = s3c_cpufreq_clk_get(NULL, "pclk");
402 	clk_arm = s3c_cpufreq_clk_get(NULL, "armclk");
403 
404 	if (IS_ERR(clk_fclk) || IS_ERR(clk_hclk) || IS_ERR(clk_pclk) ||
405 	    IS_ERR(_clk_mpll) || IS_ERR(clk_arm) || IS_ERR(_clk_xtal)) {
406 		printk(KERN_ERR "%s: could not get clock(s)\n", __func__);
407 		return -ENOENT;
408 	}
409 
410 	printk(KERN_INFO "%s: clocks f=%lu,h=%lu,p=%lu,a=%lu\n", __func__,
411 	       clk_get_rate(clk_fclk) / 1000,
412 	       clk_get_rate(clk_hclk) / 1000,
413 	       clk_get_rate(clk_pclk) / 1000,
414 	       clk_get_rate(clk_arm) / 1000);
415 
416 	return 0;
417 }
418 
419 static int s3c_cpufreq_verify(struct cpufreq_policy *policy)
420 {
421 	if (policy->cpu != 0)
422 		return -EINVAL;
423 
424 	return 0;
425 }
426 
427 #ifdef CONFIG_PM
428 static struct cpufreq_frequency_table suspend_pll;
429 static unsigned int suspend_freq;
430 
431 static int s3c_cpufreq_suspend(struct cpufreq_policy *policy)
432 {
433 	suspend_pll.frequency = clk_get_rate(_clk_mpll);
434 	suspend_pll.driver_data = __raw_readl(S3C2410_MPLLCON);
435 	suspend_freq = s3c_cpufreq_get(0) * 1000;
436 
437 	return 0;
438 }
439 
440 static int s3c_cpufreq_resume(struct cpufreq_policy *policy)
441 {
442 	int ret;
443 
444 	s3c_freq_dbg("%s: resuming with policy %p\n", __func__, policy);
445 
446 	last_target = ~0;	/* invalidate last_target setting */
447 
448 	/* first, find out what speed we resumed at. */
449 	s3c_cpufreq_resume_clocks();
450 
451 	/* whilst we will be called later on, we try and re-set the
452 	 * cpu frequencies as soon as possible so that we do not end
453 	 * up resuming devices and then immediately having to re-set
454 	 * a number of settings once these devices have restarted.
455 	 *
456 	 * as a note, it is expected devices are not used until they
457 	 * have been un-suspended and at that time they should have
458 	 * used the updated clock settings.
459 	 */
460 
461 	ret = s3c_cpufreq_settarget(NULL, suspend_freq, &suspend_pll);
462 	if (ret) {
463 		printk(KERN_ERR "%s: failed to reset pll/freq\n", __func__);
464 		return ret;
465 	}
466 
467 	return 0;
468 }
469 #else
470 #define s3c_cpufreq_resume NULL
471 #define s3c_cpufreq_suspend NULL
472 #endif
473 
474 static struct cpufreq_driver s3c24xx_driver = {
475 	.flags		= CPUFREQ_STICKY,
476 	.verify		= s3c_cpufreq_verify,
477 	.target		= s3c_cpufreq_target,
478 	.get		= s3c_cpufreq_get,
479 	.init		= s3c_cpufreq_init,
480 	.suspend	= s3c_cpufreq_suspend,
481 	.resume		= s3c_cpufreq_resume,
482 	.name		= "s3c24xx",
483 };
484 
485 
486 int __init s3c_cpufreq_register(struct s3c_cpufreq_info *info)
487 {
488 	if (!info || !info->name) {
489 		printk(KERN_ERR "%s: failed to pass valid information\n",
490 		       __func__);
491 		return -EINVAL;
492 	}
493 
494 	printk(KERN_INFO "S3C24XX CPU Frequency driver, %s cpu support\n",
495 	       info->name);
496 
497 	/* check our driver info has valid data */
498 
499 	BUG_ON(info->set_refresh == NULL);
500 	BUG_ON(info->set_divs == NULL);
501 	BUG_ON(info->calc_divs == NULL);
502 
503 	/* info->set_fvco is optional, depending on whether there
504 	 * is a need to set the clock code. */
505 
506 	cpu_cur.info = info;
507 
508 	/* Note, driver registering should probably update locktime */
509 
510 	return 0;
511 }
512 
513 int __init s3c_cpufreq_setboard(struct s3c_cpufreq_board *board)
514 {
515 	struct s3c_cpufreq_board *ours;
516 
517 	if (!board) {
518 		printk(KERN_INFO "%s: no board data\n", __func__);
519 		return -EINVAL;
520 	}
521 
522 	/* Copy the board information so that each board can make this
523 	 * initdata. */
524 
525 	ours = kzalloc(sizeof(struct s3c_cpufreq_board), GFP_KERNEL);
526 	if (ours == NULL) {
527 		printk(KERN_ERR "%s: no memory\n", __func__);
528 		return -ENOMEM;
529 	}
530 
531 	*ours = *board;
532 	cpu_cur.board = ours;
533 
534 	return 0;
535 }
536 
537 int __init s3c_cpufreq_auto_io(void)
538 {
539 	int ret;
540 
541 	if (!cpu_cur.info->get_iotiming) {
542 		printk(KERN_ERR "%s: get_iotiming undefined\n", __func__);
543 		return -ENOENT;
544 	}
545 
546 	printk(KERN_INFO "%s: working out IO settings\n", __func__);
547 
548 	ret = (cpu_cur.info->get_iotiming)(&cpu_cur, &s3c24xx_iotiming);
549 	if (ret)
550 		printk(KERN_ERR "%s: failed to get timings\n", __func__);
551 
552 	return ret;
553 }
554 
555 /* if one or is zero, then return the other, otherwise return the min */
556 #define do_min(_a, _b) ((_a) == 0 ? (_b) : (_b) == 0 ? (_a) : min(_a, _b))
557 
558 /**
559  * s3c_cpufreq_freq_min - find the minimum settings for the given freq.
560  * @dst: The destination structure
561  * @a: One argument.
562  * @b: The other argument.
563  *
564  * Create a minimum of each frequency entry in the 'struct s3c_freq',
565  * unless the entry is zero when it is ignored and the non-zero argument
566  * used.
567  */
568 static void s3c_cpufreq_freq_min(struct s3c_freq *dst,
569 				 struct s3c_freq *a, struct s3c_freq *b)
570 {
571 	dst->fclk = do_min(a->fclk, b->fclk);
572 	dst->hclk = do_min(a->hclk, b->hclk);
573 	dst->pclk = do_min(a->pclk, b->pclk);
574 	dst->armclk = do_min(a->armclk, b->armclk);
575 }
576 
577 static inline u32 calc_locktime(u32 freq, u32 time_us)
578 {
579 	u32 result;
580 
581 	result = freq * time_us;
582 	result = DIV_ROUND_UP(result, 1000 * 1000);
583 
584 	return result;
585 }
586 
587 static void s3c_cpufreq_update_loctkime(void)
588 {
589 	unsigned int bits = cpu_cur.info->locktime_bits;
590 	u32 rate = (u32)clk_get_rate(_clk_xtal);
591 	u32 val;
592 
593 	if (bits == 0) {
594 		WARN_ON(1);
595 		return;
596 	}
597 
598 	val = calc_locktime(rate, cpu_cur.info->locktime_u) << bits;
599 	val |= calc_locktime(rate, cpu_cur.info->locktime_m);
600 
601 	printk(KERN_INFO "%s: new locktime is 0x%08x\n", __func__, val);
602 	__raw_writel(val, S3C2410_LOCKTIME);
603 }
604 
605 static int s3c_cpufreq_build_freq(void)
606 {
607 	int size, ret;
608 
609 	if (!cpu_cur.info->calc_freqtable)
610 		return -EINVAL;
611 
612 	kfree(ftab);
613 	ftab = NULL;
614 
615 	size = cpu_cur.info->calc_freqtable(&cpu_cur, NULL, 0);
616 	size++;
617 
618 	ftab = kmalloc(sizeof(struct cpufreq_frequency_table) * size, GFP_KERNEL);
619 	if (!ftab) {
620 		printk(KERN_ERR "%s: no memory for tables\n", __func__);
621 		return -ENOMEM;
622 	}
623 
624 	ftab_size = size;
625 
626 	ret = cpu_cur.info->calc_freqtable(&cpu_cur, ftab, size);
627 	s3c_cpufreq_addfreq(ftab, ret, size, CPUFREQ_TABLE_END);
628 
629 	return 0;
630 }
631 
632 static int __init s3c_cpufreq_initcall(void)
633 {
634 	int ret = 0;
635 
636 	if (cpu_cur.info && cpu_cur.board) {
637 		ret = s3c_cpufreq_initclks();
638 		if (ret)
639 			goto out;
640 
641 		/* get current settings */
642 		s3c_cpufreq_getcur(&cpu_cur);
643 		s3c_cpufreq_show("cur", &cpu_cur);
644 
645 		if (cpu_cur.board->auto_io) {
646 			ret = s3c_cpufreq_auto_io();
647 			if (ret) {
648 				printk(KERN_ERR "%s: failed to get io timing\n",
649 				       __func__);
650 				goto out;
651 			}
652 		}
653 
654 		if (cpu_cur.board->need_io && !cpu_cur.info->set_iotiming) {
655 			printk(KERN_ERR "%s: no IO support registered\n",
656 			       __func__);
657 			ret = -EINVAL;
658 			goto out;
659 		}
660 
661 		if (!cpu_cur.info->need_pll)
662 			cpu_cur.lock_pll = 1;
663 
664 		s3c_cpufreq_update_loctkime();
665 
666 		s3c_cpufreq_freq_min(&cpu_cur.max, &cpu_cur.board->max,
667 				     &cpu_cur.info->max);
668 
669 		if (cpu_cur.info->calc_freqtable)
670 			s3c_cpufreq_build_freq();
671 
672 		ret = cpufreq_register_driver(&s3c24xx_driver);
673 	}
674 
675  out:
676 	return ret;
677 }
678 
679 late_initcall(s3c_cpufreq_initcall);
680 
681 /**
682  * s3c_plltab_register - register CPU PLL table.
683  * @plls: The list of PLL entries.
684  * @plls_no: The size of the PLL entries @plls.
685  *
686  * Register the given set of PLLs with the system.
687  */
688 int __init s3c_plltab_register(struct cpufreq_frequency_table *plls,
689 			       unsigned int plls_no)
690 {
691 	struct cpufreq_frequency_table *vals;
692 	unsigned int size;
693 
694 	size = sizeof(struct cpufreq_frequency_table) * (plls_no + 1);
695 
696 	vals = kmalloc(size, GFP_KERNEL);
697 	if (vals) {
698 		memcpy(vals, plls, size);
699 		pll_reg = vals;
700 
701 		/* write a terminating entry, we don't store it in the
702 		 * table that is stored in the kernel */
703 		vals += plls_no;
704 		vals->frequency = CPUFREQ_TABLE_END;
705 
706 		printk(KERN_INFO "cpufreq: %d PLL entries\n", plls_no);
707 	} else
708 		printk(KERN_ERR "cpufreq: no memory for PLL tables\n");
709 
710 	return vals ? 0 : -ENOMEM;
711 }
712