GNU Linux-libre 6.8.9-gnu
[releases.git] / drivers / clk / ti / fapll.c
1 // SPDX-License-Identifier: GPL-2.0-only
2
3 #include <linux/clk.h>
4 #include <linux/clk-provider.h>
5 #include <linux/delay.h>
6 #include <linux/err.h>
7 #include <linux/io.h>
8 #include <linux/math64.h>
9 #include <linux/of.h>
10 #include <linux/of_address.h>
11 #include <linux/clk/ti.h>
12
13 #include "clock.h"
14
15 /* FAPLL Control Register PLL_CTRL */
16 #define FAPLL_MAIN_MULT_N_SHIFT 16
17 #define FAPLL_MAIN_DIV_P_SHIFT  8
18 #define FAPLL_MAIN_LOCK         BIT(7)
19 #define FAPLL_MAIN_PLLEN        BIT(3)
20 #define FAPLL_MAIN_BP           BIT(2)
21 #define FAPLL_MAIN_LOC_CTL      BIT(0)
22
23 #define FAPLL_MAIN_MAX_MULT_N   0xffff
24 #define FAPLL_MAIN_MAX_DIV_P    0xff
25 #define FAPLL_MAIN_CLEAR_MASK   \
26         ((FAPLL_MAIN_MAX_MULT_N << FAPLL_MAIN_MULT_N_SHIFT) | \
27          (FAPLL_MAIN_DIV_P_SHIFT << FAPLL_MAIN_DIV_P_SHIFT) | \
28          FAPLL_MAIN_LOC_CTL)
29
30 /* FAPLL powerdown register PWD */
31 #define FAPLL_PWD_OFFSET        4
32
33 #define MAX_FAPLL_OUTPUTS       7
34 #define FAPLL_MAX_RETRIES       1000
35
36 #define to_fapll(_hw)           container_of(_hw, struct fapll_data, hw)
37 #define to_synth(_hw)           container_of(_hw, struct fapll_synth, hw)
38
39 /* The bypass bit is inverted on the ddr_pll.. */
40 #define fapll_is_ddr_pll(va)    (((u32)(va) & 0xffff) == 0x0440)
41
42 /*
43  * The audio_pll_clk1 input is hard wired to the 27MHz bypass clock,
44  * and the audio_pll_clk1 synthesizer is hardwared to 32KiHz output.
45  */
46 #define is_ddr_pll_clk1(va)     (((u32)(va) & 0xffff) == 0x044c)
47 #define is_audio_pll_clk1(va)   (((u32)(va) & 0xffff) == 0x04a8)
48
49 /* Synthesizer divider register */
50 #define SYNTH_LDMDIV1           BIT(8)
51
52 /* Synthesizer frequency register */
53 #define SYNTH_LDFREQ            BIT(31)
54
55 #define SYNTH_PHASE_K           8
56 #define SYNTH_MAX_INT_DIV       0xf
57 #define SYNTH_MAX_DIV_M         0xff
58
59 struct fapll_data {
60         struct clk_hw hw;
61         void __iomem *base;
62         const char *name;
63         struct clk *clk_ref;
64         struct clk *clk_bypass;
65         struct clk_onecell_data outputs;
66         bool bypass_bit_inverted;
67 };
68
69 struct fapll_synth {
70         struct clk_hw hw;
71         struct fapll_data *fd;
72         int index;
73         void __iomem *freq;
74         void __iomem *div;
75         const char *name;
76         struct clk *clk_pll;
77 };
78
79 static bool ti_fapll_clock_is_bypass(struct fapll_data *fd)
80 {
81         u32 v = readl_relaxed(fd->base);
82
83         if (fd->bypass_bit_inverted)
84                 return !(v & FAPLL_MAIN_BP);
85         else
86                 return !!(v & FAPLL_MAIN_BP);
87 }
88
89 static void ti_fapll_set_bypass(struct fapll_data *fd)
90 {
91         u32 v = readl_relaxed(fd->base);
92
93         if (fd->bypass_bit_inverted)
94                 v &= ~FAPLL_MAIN_BP;
95         else
96                 v |= FAPLL_MAIN_BP;
97         writel_relaxed(v, fd->base);
98 }
99
100 static void ti_fapll_clear_bypass(struct fapll_data *fd)
101 {
102         u32 v = readl_relaxed(fd->base);
103
104         if (fd->bypass_bit_inverted)
105                 v |= FAPLL_MAIN_BP;
106         else
107                 v &= ~FAPLL_MAIN_BP;
108         writel_relaxed(v, fd->base);
109 }
110
111 static int ti_fapll_wait_lock(struct fapll_data *fd)
112 {
113         int retries = FAPLL_MAX_RETRIES;
114         u32 v;
115
116         while ((v = readl_relaxed(fd->base))) {
117                 if (v & FAPLL_MAIN_LOCK)
118                         return 0;
119
120                 if (retries-- <= 0)
121                         break;
122
123                 udelay(1);
124         }
125
126         pr_err("%s failed to lock\n", fd->name);
127
128         return -ETIMEDOUT;
129 }
130
131 static int ti_fapll_enable(struct clk_hw *hw)
132 {
133         struct fapll_data *fd = to_fapll(hw);
134         u32 v = readl_relaxed(fd->base);
135
136         v |= FAPLL_MAIN_PLLEN;
137         writel_relaxed(v, fd->base);
138         ti_fapll_wait_lock(fd);
139
140         return 0;
141 }
142
143 static void ti_fapll_disable(struct clk_hw *hw)
144 {
145         struct fapll_data *fd = to_fapll(hw);
146         u32 v = readl_relaxed(fd->base);
147
148         v &= ~FAPLL_MAIN_PLLEN;
149         writel_relaxed(v, fd->base);
150 }
151
152 static int ti_fapll_is_enabled(struct clk_hw *hw)
153 {
154         struct fapll_data *fd = to_fapll(hw);
155         u32 v = readl_relaxed(fd->base);
156
157         return v & FAPLL_MAIN_PLLEN;
158 }
159
160 static unsigned long ti_fapll_recalc_rate(struct clk_hw *hw,
161                                           unsigned long parent_rate)
162 {
163         struct fapll_data *fd = to_fapll(hw);
164         u32 fapll_n, fapll_p, v;
165         u64 rate;
166
167         if (ti_fapll_clock_is_bypass(fd))
168                 return parent_rate;
169
170         rate = parent_rate;
171
172         /* PLL pre-divider is P and multiplier is N */
173         v = readl_relaxed(fd->base);
174         fapll_p = (v >> 8) & 0xff;
175         if (fapll_p)
176                 do_div(rate, fapll_p);
177         fapll_n = v >> 16;
178         if (fapll_n)
179                 rate *= fapll_n;
180
181         return rate;
182 }
183
184 static u8 ti_fapll_get_parent(struct clk_hw *hw)
185 {
186         struct fapll_data *fd = to_fapll(hw);
187
188         if (ti_fapll_clock_is_bypass(fd))
189                 return 1;
190
191         return 0;
192 }
193
194 static int ti_fapll_set_div_mult(unsigned long rate,
195                                  unsigned long parent_rate,
196                                  u32 *pre_div_p, u32 *mult_n)
197 {
198         /*
199          * So far no luck getting decent clock with PLL divider,
200          * PLL does not seem to lock and the signal does not look
201          * right. It seems the divider can only be used together
202          * with the multiplier?
203          */
204         if (rate < parent_rate) {
205                 pr_warn("FAPLL main divider rates unsupported\n");
206                 return -EINVAL;
207         }
208
209         *mult_n = rate / parent_rate;
210         if (*mult_n > FAPLL_MAIN_MAX_MULT_N)
211                 return -EINVAL;
212         *pre_div_p = 1;
213
214         return 0;
215 }
216
217 static long ti_fapll_round_rate(struct clk_hw *hw, unsigned long rate,
218                                 unsigned long *parent_rate)
219 {
220         u32 pre_div_p, mult_n;
221         int error;
222
223         if (!rate)
224                 return -EINVAL;
225
226         error = ti_fapll_set_div_mult(rate, *parent_rate,
227                                       &pre_div_p, &mult_n);
228         if (error)
229                 return error;
230
231         rate = *parent_rate / pre_div_p;
232         rate *= mult_n;
233
234         return rate;
235 }
236
237 static int ti_fapll_set_rate(struct clk_hw *hw, unsigned long rate,
238                              unsigned long parent_rate)
239 {
240         struct fapll_data *fd = to_fapll(hw);
241         u32 pre_div_p, mult_n, v;
242         int error;
243
244         if (!rate)
245                 return -EINVAL;
246
247         error = ti_fapll_set_div_mult(rate, parent_rate,
248                                       &pre_div_p, &mult_n);
249         if (error)
250                 return error;
251
252         ti_fapll_set_bypass(fd);
253         v = readl_relaxed(fd->base);
254         v &= ~FAPLL_MAIN_CLEAR_MASK;
255         v |= pre_div_p << FAPLL_MAIN_DIV_P_SHIFT;
256         v |= mult_n << FAPLL_MAIN_MULT_N_SHIFT;
257         writel_relaxed(v, fd->base);
258         if (ti_fapll_is_enabled(hw))
259                 ti_fapll_wait_lock(fd);
260         ti_fapll_clear_bypass(fd);
261
262         return 0;
263 }
264
265 static const struct clk_ops ti_fapll_ops = {
266         .enable = ti_fapll_enable,
267         .disable = ti_fapll_disable,
268         .is_enabled = ti_fapll_is_enabled,
269         .recalc_rate = ti_fapll_recalc_rate,
270         .get_parent = ti_fapll_get_parent,
271         .round_rate = ti_fapll_round_rate,
272         .set_rate = ti_fapll_set_rate,
273 };
274
275 static int ti_fapll_synth_enable(struct clk_hw *hw)
276 {
277         struct fapll_synth *synth = to_synth(hw);
278         u32 v = readl_relaxed(synth->fd->base + FAPLL_PWD_OFFSET);
279
280         v &= ~(1 << synth->index);
281         writel_relaxed(v, synth->fd->base + FAPLL_PWD_OFFSET);
282
283         return 0;
284 }
285
286 static void ti_fapll_synth_disable(struct clk_hw *hw)
287 {
288         struct fapll_synth *synth = to_synth(hw);
289         u32 v = readl_relaxed(synth->fd->base + FAPLL_PWD_OFFSET);
290
291         v |= 1 << synth->index;
292         writel_relaxed(v, synth->fd->base + FAPLL_PWD_OFFSET);
293 }
294
295 static int ti_fapll_synth_is_enabled(struct clk_hw *hw)
296 {
297         struct fapll_synth *synth = to_synth(hw);
298         u32 v = readl_relaxed(synth->fd->base + FAPLL_PWD_OFFSET);
299
300         return !(v & (1 << synth->index));
301 }
302
303 /*
304  * See dm816x TRM chapter 1.10.3 Flying Adder PLL fore more info
305  */
306 static unsigned long ti_fapll_synth_recalc_rate(struct clk_hw *hw,
307                                                 unsigned long parent_rate)
308 {
309         struct fapll_synth *synth = to_synth(hw);
310         u32 synth_div_m;
311         u64 rate;
312
313         /* The audio_pll_clk1 is hardwired to produce 32.768KiHz clock */
314         if (!synth->div)
315                 return 32768;
316
317         /*
318          * PLL in bypass sets the synths in bypass mode too. The PLL rate
319          * can be also be set to 27MHz, so we can't use parent_rate to
320          * check for bypass mode.
321          */
322         if (ti_fapll_clock_is_bypass(synth->fd))
323                 return parent_rate;
324
325         rate = parent_rate;
326
327         /*
328          * Synth frequency integer and fractional divider.
329          * Note that the phase output K is 8, so the result needs
330          * to be multiplied by SYNTH_PHASE_K.
331          */
332         if (synth->freq) {
333                 u32 v, synth_int_div, synth_frac_div, synth_div_freq;
334
335                 v = readl_relaxed(synth->freq);
336                 synth_int_div = (v >> 24) & 0xf;
337                 synth_frac_div = v & 0xffffff;
338                 synth_div_freq = (synth_int_div * 10000000) + synth_frac_div;
339                 rate *= 10000000;
340                 do_div(rate, synth_div_freq);
341                 rate *= SYNTH_PHASE_K;
342         }
343
344         /* Synth post-divider M */
345         synth_div_m = readl_relaxed(synth->div) & SYNTH_MAX_DIV_M;
346
347         return DIV_ROUND_UP_ULL(rate, synth_div_m);
348 }
349
350 static unsigned long ti_fapll_synth_get_frac_rate(struct clk_hw *hw,
351                                                   unsigned long parent_rate)
352 {
353         struct fapll_synth *synth = to_synth(hw);
354         unsigned long current_rate, frac_rate;
355         u32 post_div_m;
356
357         current_rate = ti_fapll_synth_recalc_rate(hw, parent_rate);
358         post_div_m = readl_relaxed(synth->div) & SYNTH_MAX_DIV_M;
359         frac_rate = current_rate * post_div_m;
360
361         return frac_rate;
362 }
363
364 static u32 ti_fapll_synth_set_frac_rate(struct fapll_synth *synth,
365                                         unsigned long rate,
366                                         unsigned long parent_rate)
367 {
368         u32 post_div_m, synth_int_div = 0, synth_frac_div = 0, v;
369
370         post_div_m = DIV_ROUND_UP_ULL((u64)parent_rate * SYNTH_PHASE_K, rate);
371         post_div_m = post_div_m / SYNTH_MAX_INT_DIV;
372         if (post_div_m > SYNTH_MAX_DIV_M)
373                 return -EINVAL;
374         if (!post_div_m)
375                 post_div_m = 1;
376
377         for (; post_div_m < SYNTH_MAX_DIV_M; post_div_m++) {
378                 synth_int_div = DIV_ROUND_UP_ULL((u64)parent_rate *
379                                                  SYNTH_PHASE_K *
380                                                  10000000,
381                                                  rate * post_div_m);
382                 synth_frac_div = synth_int_div % 10000000;
383                 synth_int_div /= 10000000;
384
385                 if (synth_int_div <= SYNTH_MAX_INT_DIV)
386                         break;
387         }
388
389         if (synth_int_div > SYNTH_MAX_INT_DIV)
390                 return -EINVAL;
391
392         v = readl_relaxed(synth->freq);
393         v &= ~0x1fffffff;
394         v |= (synth_int_div & SYNTH_MAX_INT_DIV) << 24;
395         v |= (synth_frac_div & 0xffffff);
396         v |= SYNTH_LDFREQ;
397         writel_relaxed(v, synth->freq);
398
399         return post_div_m;
400 }
401
402 static long ti_fapll_synth_round_rate(struct clk_hw *hw, unsigned long rate,
403                                       unsigned long *parent_rate)
404 {
405         struct fapll_synth *synth = to_synth(hw);
406         struct fapll_data *fd = synth->fd;
407         unsigned long r;
408
409         if (ti_fapll_clock_is_bypass(fd) || !synth->div || !rate)
410                 return -EINVAL;
411
412         /* Only post divider m available with no fractional divider? */
413         if (!synth->freq) {
414                 unsigned long frac_rate;
415                 u32 synth_post_div_m;
416
417                 frac_rate = ti_fapll_synth_get_frac_rate(hw, *parent_rate);
418                 synth_post_div_m = DIV_ROUND_UP(frac_rate, rate);
419                 r = DIV_ROUND_UP(frac_rate, synth_post_div_m);
420                 goto out;
421         }
422
423         r = *parent_rate * SYNTH_PHASE_K;
424         if (rate > r)
425                 goto out;
426
427         r = DIV_ROUND_UP_ULL(r, SYNTH_MAX_INT_DIV * SYNTH_MAX_DIV_M);
428         if (rate < r)
429                 goto out;
430
431         r = rate;
432 out:
433         return r;
434 }
435
436 static int ti_fapll_synth_set_rate(struct clk_hw *hw, unsigned long rate,
437                                    unsigned long parent_rate)
438 {
439         struct fapll_synth *synth = to_synth(hw);
440         struct fapll_data *fd = synth->fd;
441         unsigned long frac_rate, post_rate = 0;
442         u32 post_div_m = 0, v;
443
444         if (ti_fapll_clock_is_bypass(fd) || !synth->div || !rate)
445                 return -EINVAL;
446
447         /* Produce the rate with just post divider M? */
448         frac_rate = ti_fapll_synth_get_frac_rate(hw, parent_rate);
449         if (frac_rate < rate) {
450                 if (!synth->freq)
451                         return -EINVAL;
452         } else {
453                 post_div_m = DIV_ROUND_UP(frac_rate, rate);
454                 if (post_div_m && (post_div_m <= SYNTH_MAX_DIV_M))
455                         post_rate = DIV_ROUND_UP(frac_rate, post_div_m);
456                 if (!synth->freq && !post_rate)
457                         return -EINVAL;
458         }
459
460         /* Need to recalculate the fractional divider? */
461         if ((post_rate != rate) && synth->freq)
462                 post_div_m = ti_fapll_synth_set_frac_rate(synth,
463                                                           rate,
464                                                           parent_rate);
465
466         v = readl_relaxed(synth->div);
467         v &= ~SYNTH_MAX_DIV_M;
468         v |= post_div_m;
469         v |= SYNTH_LDMDIV1;
470         writel_relaxed(v, synth->div);
471
472         return 0;
473 }
474
475 static const struct clk_ops ti_fapll_synt_ops = {
476         .enable = ti_fapll_synth_enable,
477         .disable = ti_fapll_synth_disable,
478         .is_enabled = ti_fapll_synth_is_enabled,
479         .recalc_rate = ti_fapll_synth_recalc_rate,
480         .round_rate = ti_fapll_synth_round_rate,
481         .set_rate = ti_fapll_synth_set_rate,
482 };
483
484 static struct clk * __init ti_fapll_synth_setup(struct fapll_data *fd,
485                                                 void __iomem *freq,
486                                                 void __iomem *div,
487                                                 int index,
488                                                 const char *name,
489                                                 const char *parent,
490                                                 struct clk *pll_clk)
491 {
492         struct clk_init_data *init;
493         struct fapll_synth *synth;
494         struct clk *clk = ERR_PTR(-ENOMEM);
495
496         init = kzalloc(sizeof(*init), GFP_KERNEL);
497         if (!init)
498                 return ERR_PTR(-ENOMEM);
499
500         init->ops = &ti_fapll_synt_ops;
501         init->name = name;
502         init->parent_names = &parent;
503         init->num_parents = 1;
504
505         synth = kzalloc(sizeof(*synth), GFP_KERNEL);
506         if (!synth)
507                 goto free;
508
509         synth->fd = fd;
510         synth->index = index;
511         synth->freq = freq;
512         synth->div = div;
513         synth->name = name;
514         synth->hw.init = init;
515         synth->clk_pll = pll_clk;
516
517         clk = clk_register(NULL, &synth->hw);
518         if (IS_ERR(clk)) {
519                 pr_err("failed to register clock\n");
520                 goto free;
521         }
522
523         return clk;
524
525 free:
526         kfree(synth);
527         kfree(init);
528
529         return clk;
530 }
531
532 static void __init ti_fapll_setup(struct device_node *node)
533 {
534         struct fapll_data *fd;
535         struct clk_init_data *init = NULL;
536         const char *parent_name[2];
537         struct clk *pll_clk;
538         const char *name;
539         int i;
540
541         fd = kzalloc(sizeof(*fd), GFP_KERNEL);
542         if (!fd)
543                 return;
544
545         fd->outputs.clks = kzalloc(sizeof(struct clk *) *
546                                    MAX_FAPLL_OUTPUTS + 1,
547                                    GFP_KERNEL);
548         if (!fd->outputs.clks)
549                 goto free;
550
551         init = kzalloc(sizeof(*init), GFP_KERNEL);
552         if (!init)
553                 goto free;
554
555         init->ops = &ti_fapll_ops;
556         name = ti_dt_clk_name(node);
557         init->name = name;
558
559         init->num_parents = of_clk_get_parent_count(node);
560         if (init->num_parents != 2) {
561                 pr_err("%pOFn must have two parents\n", node);
562                 goto free;
563         }
564
565         of_clk_parent_fill(node, parent_name, 2);
566         init->parent_names = parent_name;
567
568         fd->clk_ref = of_clk_get(node, 0);
569         if (IS_ERR(fd->clk_ref)) {
570                 pr_err("%pOFn could not get clk_ref\n", node);
571                 goto free;
572         }
573
574         fd->clk_bypass = of_clk_get(node, 1);
575         if (IS_ERR(fd->clk_bypass)) {
576                 pr_err("%pOFn could not get clk_bypass\n", node);
577                 goto free;
578         }
579
580         fd->base = of_iomap(node, 0);
581         if (!fd->base) {
582                 pr_err("%pOFn could not get IO base\n", node);
583                 goto free;
584         }
585
586         if (fapll_is_ddr_pll(fd->base))
587                 fd->bypass_bit_inverted = true;
588
589         fd->name = name;
590         fd->hw.init = init;
591
592         /* Register the parent PLL */
593         pll_clk = clk_register(NULL, &fd->hw);
594         if (IS_ERR(pll_clk))
595                 goto unmap;
596
597         fd->outputs.clks[0] = pll_clk;
598         fd->outputs.clk_num++;
599
600         /*
601          * Set up the child synthesizers starting at index 1 as the
602          * PLL output is at index 0. We need to check the clock-indices
603          * for numbering in case there are holes in the synth mapping,
604          * and then probe the synth register to see if it has a FREQ
605          * register available.
606          */
607         for (i = 0; i < MAX_FAPLL_OUTPUTS; i++) {
608                 const char *output_name;
609                 void __iomem *freq, *div;
610                 struct clk *synth_clk;
611                 int output_instance;
612                 u32 v;
613
614                 if (of_property_read_string_index(node, "clock-output-names",
615                                                   i, &output_name))
616                         continue;
617
618                 if (of_property_read_u32_index(node, "clock-indices", i,
619                                                &output_instance))
620                         output_instance = i;
621
622                 freq = fd->base + (output_instance * 8);
623                 div = freq + 4;
624
625                 /* Check for hardwired audio_pll_clk1 */
626                 if (is_audio_pll_clk1(freq)) {
627                         freq = NULL;
628                         div = NULL;
629                 } else {
630                         /* Does the synthesizer have a FREQ register? */
631                         v = readl_relaxed(freq);
632                         if (!v)
633                                 freq = NULL;
634                 }
635                 synth_clk = ti_fapll_synth_setup(fd, freq, div, output_instance,
636                                                  output_name, name, pll_clk);
637                 if (IS_ERR(synth_clk))
638                         continue;
639
640                 fd->outputs.clks[output_instance] = synth_clk;
641                 fd->outputs.clk_num++;
642
643                 clk_register_clkdev(synth_clk, output_name, NULL);
644         }
645
646         /* Register the child synthesizers as the FAPLL outputs */
647         of_clk_add_provider(node, of_clk_src_onecell_get, &fd->outputs);
648         /* Add clock alias for the outputs */
649
650         kfree(init);
651
652         return;
653
654 unmap:
655         iounmap(fd->base);
656 free:
657         if (fd->clk_bypass)
658                 clk_put(fd->clk_bypass);
659         if (fd->clk_ref)
660                 clk_put(fd->clk_ref);
661         kfree(fd->outputs.clks);
662         kfree(fd);
663         kfree(init);
664 }
665
666 CLK_OF_DECLARE(ti_fapll_clock, "ti,dm816-fapll-clock", ti_fapll_setup);