1 /*
2  * Copyright (C) 2013 Broadcom Corporation
3  * Copyright 2013 Linaro Limited
4  *
5  * This program is free software; you can redistribute it and/or
6  * modify it under the terms of the GNU General Public License as
7  * published by the Free Software Foundation version 2.
8  *
9  * This program is distributed "as is" WITHOUT ANY WARRANTY of any
10  * kind, whether express or implied; without even the implied warranty
11  * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
12  * GNU General Public License for more details.
13  */
14 
15 #include <linux/io.h>
16 #include <linux/of_address.h>
17 
18 #include "clk-kona.h"
19 
20 /* These are used when a selector or trigger is found to be unneeded */
21 #define selector_clear_exists(sel)	((sel)->width = 0)
22 #define trigger_clear_exists(trig)	FLAG_CLEAR(trig, TRIG, EXISTS)
23 
24 /* Validity checking */
25 
ccu_data_offsets_valid(struct ccu_data * ccu)26 static bool ccu_data_offsets_valid(struct ccu_data *ccu)
27 {
28 	struct ccu_policy *ccu_policy = &ccu->policy;
29 	u32 limit;
30 
31 	limit = ccu->range - sizeof(u32);
32 	limit = round_down(limit, sizeof(u32));
33 	if (ccu_policy_exists(ccu_policy)) {
34 		if (ccu_policy->enable.offset > limit) {
35 			pr_err("%s: bad policy enable offset for %s "
36 					"(%u > %u)\n", __func__,
37 				ccu->name, ccu_policy->enable.offset, limit);
38 			return false;
39 		}
40 		if (ccu_policy->control.offset > limit) {
41 			pr_err("%s: bad policy control offset for %s "
42 					"(%u > %u)\n", __func__,
43 				ccu->name, ccu_policy->control.offset, limit);
44 			return false;
45 		}
46 	}
47 
48 	return true;
49 }
50 
clk_requires_trigger(struct kona_clk * bcm_clk)51 static bool clk_requires_trigger(struct kona_clk *bcm_clk)
52 {
53 	struct peri_clk_data *peri = bcm_clk->u.peri;
54 	struct bcm_clk_sel *sel;
55 	struct bcm_clk_div *div;
56 
57 	if (bcm_clk->type != bcm_clk_peri)
58 		return false;
59 
60 	sel = &peri->sel;
61 	if (sel->parent_count && selector_exists(sel))
62 		return true;
63 
64 	div = &peri->div;
65 	if (!divider_exists(div))
66 		return false;
67 
68 	/* Fixed dividers don't need triggers */
69 	if (!divider_is_fixed(div))
70 		return true;
71 
72 	div = &peri->pre_div;
73 
74 	return divider_exists(div) && !divider_is_fixed(div);
75 }
76 
peri_clk_data_offsets_valid(struct kona_clk * bcm_clk)77 static bool peri_clk_data_offsets_valid(struct kona_clk *bcm_clk)
78 {
79 	struct peri_clk_data *peri;
80 	struct bcm_clk_policy *policy;
81 	struct bcm_clk_gate *gate;
82 	struct bcm_clk_hyst *hyst;
83 	struct bcm_clk_div *div;
84 	struct bcm_clk_sel *sel;
85 	struct bcm_clk_trig *trig;
86 	const char *name;
87 	u32 range;
88 	u32 limit;
89 
90 	BUG_ON(bcm_clk->type != bcm_clk_peri);
91 	peri = bcm_clk->u.peri;
92 	name = bcm_clk->init_data.name;
93 	range = bcm_clk->ccu->range;
94 
95 	limit = range - sizeof(u32);
96 	limit = round_down(limit, sizeof(u32));
97 
98 	policy = &peri->policy;
99 	if (policy_exists(policy)) {
100 		if (policy->offset > limit) {
101 			pr_err("%s: bad policy offset for %s (%u > %u)\n",
102 				__func__, name, policy->offset, limit);
103 			return false;
104 		}
105 	}
106 
107 	gate = &peri->gate;
108 	hyst = &peri->hyst;
109 	if (gate_exists(gate)) {
110 		if (gate->offset > limit) {
111 			pr_err("%s: bad gate offset for %s (%u > %u)\n",
112 				__func__, name, gate->offset, limit);
113 			return false;
114 		}
115 
116 		if (hyst_exists(hyst)) {
117 			if (hyst->offset > limit) {
118 				pr_err("%s: bad hysteresis offset for %s "
119 					"(%u > %u)\n", __func__,
120 					name, hyst->offset, limit);
121 				return false;
122 			}
123 		}
124 	} else if (hyst_exists(hyst)) {
125 		pr_err("%s: hysteresis but no gate for %s\n", __func__, name);
126 		return false;
127 	}
128 
129 	div = &peri->div;
130 	if (divider_exists(div)) {
131 		if (div->u.s.offset > limit) {
132 			pr_err("%s: bad divider offset for %s (%u > %u)\n",
133 				__func__, name, div->u.s.offset, limit);
134 			return false;
135 		}
136 	}
137 
138 	div = &peri->pre_div;
139 	if (divider_exists(div)) {
140 		if (div->u.s.offset > limit) {
141 			pr_err("%s: bad pre-divider offset for %s "
142 					"(%u > %u)\n",
143 				__func__, name, div->u.s.offset, limit);
144 			return false;
145 		}
146 	}
147 
148 	sel = &peri->sel;
149 	if (selector_exists(sel)) {
150 		if (sel->offset > limit) {
151 			pr_err("%s: bad selector offset for %s (%u > %u)\n",
152 				__func__, name, sel->offset, limit);
153 			return false;
154 		}
155 	}
156 
157 	trig = &peri->trig;
158 	if (trigger_exists(trig)) {
159 		if (trig->offset > limit) {
160 			pr_err("%s: bad trigger offset for %s (%u > %u)\n",
161 				__func__, name, trig->offset, limit);
162 			return false;
163 		}
164 	}
165 
166 	trig = &peri->pre_trig;
167 	if (trigger_exists(trig)) {
168 		if (trig->offset > limit) {
169 			pr_err("%s: bad pre-trigger offset for %s (%u > %u)\n",
170 				__func__, name, trig->offset, limit);
171 			return false;
172 		}
173 	}
174 
175 	return true;
176 }
177 
178 /* A bit position must be less than the number of bits in a 32-bit register. */
bit_posn_valid(u32 bit_posn,const char * field_name,const char * clock_name)179 static bool bit_posn_valid(u32 bit_posn, const char *field_name,
180 			const char *clock_name)
181 {
182 	u32 limit = BITS_PER_BYTE * sizeof(u32) - 1;
183 
184 	if (bit_posn > limit) {
185 		pr_err("%s: bad %s bit for %s (%u > %u)\n", __func__,
186 			field_name, clock_name, bit_posn, limit);
187 		return false;
188 	}
189 	return true;
190 }
191 
192 /*
193  * A bitfield must be at least 1 bit wide.  Both the low-order and
194  * high-order bits must lie within a 32-bit register.  We require
195  * fields to be less than 32 bits wide, mainly because we use
196  * shifting to produce field masks, and shifting a full word width
197  * is not well-defined by the C standard.
198  */
bitfield_valid(u32 shift,u32 width,const char * field_name,const char * clock_name)199 static bool bitfield_valid(u32 shift, u32 width, const char *field_name,
200 			const char *clock_name)
201 {
202 	u32 limit = BITS_PER_BYTE * sizeof(u32);
203 
204 	if (!width) {
205 		pr_err("%s: bad %s field width 0 for %s\n", __func__,
206 			field_name, clock_name);
207 		return false;
208 	}
209 	if (shift + width > limit) {
210 		pr_err("%s: bad %s for %s (%u + %u > %u)\n", __func__,
211 			field_name, clock_name, shift, width, limit);
212 		return false;
213 	}
214 	return true;
215 }
216 
217 static bool
ccu_policy_valid(struct ccu_policy * ccu_policy,const char * ccu_name)218 ccu_policy_valid(struct ccu_policy *ccu_policy, const char *ccu_name)
219 {
220 	struct bcm_lvm_en *enable = &ccu_policy->enable;
221 	struct bcm_policy_ctl *control;
222 
223 	if (!bit_posn_valid(enable->bit, "policy enable", ccu_name))
224 		return false;
225 
226 	control = &ccu_policy->control;
227 	if (!bit_posn_valid(control->go_bit, "policy control GO", ccu_name))
228 		return false;
229 
230 	if (!bit_posn_valid(control->atl_bit, "policy control ATL", ccu_name))
231 		return false;
232 
233 	if (!bit_posn_valid(control->ac_bit, "policy control AC", ccu_name))
234 		return false;
235 
236 	return true;
237 }
238 
policy_valid(struct bcm_clk_policy * policy,const char * clock_name)239 static bool policy_valid(struct bcm_clk_policy *policy, const char *clock_name)
240 {
241 	if (!bit_posn_valid(policy->bit, "policy", clock_name))
242 		return false;
243 
244 	return true;
245 }
246 
247 /*
248  * All gates, if defined, have a status bit, and for hardware-only
249  * gates, that's it.  Gates that can be software controlled also
250  * have an enable bit.  And a gate that can be hardware or software
251  * controlled will have a hardware/software select bit.
252  */
gate_valid(struct bcm_clk_gate * gate,const char * field_name,const char * clock_name)253 static bool gate_valid(struct bcm_clk_gate *gate, const char *field_name,
254 			const char *clock_name)
255 {
256 	if (!bit_posn_valid(gate->status_bit, "gate status", clock_name))
257 		return false;
258 
259 	if (gate_is_sw_controllable(gate)) {
260 		if (!bit_posn_valid(gate->en_bit, "gate enable", clock_name))
261 			return false;
262 
263 		if (gate_is_hw_controllable(gate)) {
264 			if (!bit_posn_valid(gate->hw_sw_sel_bit,
265 						"gate hw/sw select",
266 						clock_name))
267 				return false;
268 		}
269 	} else {
270 		BUG_ON(!gate_is_hw_controllable(gate));
271 	}
272 
273 	return true;
274 }
275 
hyst_valid(struct bcm_clk_hyst * hyst,const char * clock_name)276 static bool hyst_valid(struct bcm_clk_hyst *hyst, const char *clock_name)
277 {
278 	if (!bit_posn_valid(hyst->en_bit, "hysteresis enable", clock_name))
279 		return false;
280 
281 	if (!bit_posn_valid(hyst->val_bit, "hysteresis value", clock_name))
282 		return false;
283 
284 	return true;
285 }
286 
287 /*
288  * A selector bitfield must be valid.  Its parent_sel array must
289  * also be reasonable for the field.
290  */
sel_valid(struct bcm_clk_sel * sel,const char * field_name,const char * clock_name)291 static bool sel_valid(struct bcm_clk_sel *sel, const char *field_name,
292 			const char *clock_name)
293 {
294 	if (!bitfield_valid(sel->shift, sel->width, field_name, clock_name))
295 		return false;
296 
297 	if (sel->parent_count) {
298 		u32 max_sel;
299 		u32 limit;
300 
301 		/*
302 		 * Make sure the selector field can hold all the
303 		 * selector values we expect to be able to use.  A
304 		 * clock only needs to have a selector defined if it
305 		 * has more than one parent.  And in that case the
306 		 * highest selector value will be in the last entry
307 		 * in the array.
308 		 */
309 		max_sel = sel->parent_sel[sel->parent_count - 1];
310 		limit = (1 << sel->width) - 1;
311 		if (max_sel > limit) {
312 			pr_err("%s: bad selector for %s "
313 					"(%u needs > %u bits)\n",
314 				__func__, clock_name, max_sel,
315 				sel->width);
316 			return false;
317 		}
318 	} else {
319 		pr_warn("%s: ignoring selector for %s (no parents)\n",
320 			__func__, clock_name);
321 		selector_clear_exists(sel);
322 		kfree(sel->parent_sel);
323 		sel->parent_sel = NULL;
324 	}
325 
326 	return true;
327 }
328 
329 /*
330  * A fixed divider just needs to be non-zero.  A variable divider
331  * has to have a valid divider bitfield, and if it has a fraction,
332  * the width of the fraction must not be no more than the width of
333  * the divider as a whole.
334  */
div_valid(struct bcm_clk_div * div,const char * field_name,const char * clock_name)335 static bool div_valid(struct bcm_clk_div *div, const char *field_name,
336 			const char *clock_name)
337 {
338 	if (divider_is_fixed(div)) {
339 		/* Any fixed divider value but 0 is OK */
340 		if (div->u.fixed == 0) {
341 			pr_err("%s: bad %s fixed value 0 for %s\n", __func__,
342 				field_name, clock_name);
343 			return false;
344 		}
345 		return true;
346 	}
347 	if (!bitfield_valid(div->u.s.shift, div->u.s.width,
348 				field_name, clock_name))
349 		return false;
350 
351 	if (divider_has_fraction(div))
352 		if (div->u.s.frac_width > div->u.s.width) {
353 			pr_warn("%s: bad %s fraction width for %s (%u > %u)\n",
354 				__func__, field_name, clock_name,
355 				div->u.s.frac_width, div->u.s.width);
356 			return false;
357 		}
358 
359 	return true;
360 }
361 
362 /*
363  * If a clock has two dividers, the combined number of fractional
364  * bits must be representable in a 32-bit unsigned value.  This
365  * is because we scale up a dividend using both dividers before
366  * dividing to improve accuracy, and we need to avoid overflow.
367  */
kona_dividers_valid(struct kona_clk * bcm_clk)368 static bool kona_dividers_valid(struct kona_clk *bcm_clk)
369 {
370 	struct peri_clk_data *peri = bcm_clk->u.peri;
371 	struct bcm_clk_div *div;
372 	struct bcm_clk_div *pre_div;
373 	u32 limit;
374 
375 	BUG_ON(bcm_clk->type != bcm_clk_peri);
376 
377 	if (!divider_exists(&peri->div) || !divider_exists(&peri->pre_div))
378 		return true;
379 
380 	div = &peri->div;
381 	pre_div = &peri->pre_div;
382 	if (divider_is_fixed(div) || divider_is_fixed(pre_div))
383 		return true;
384 
385 	limit = BITS_PER_BYTE * sizeof(u32);
386 
387 	return div->u.s.frac_width + pre_div->u.s.frac_width <= limit;
388 }
389 
390 
391 /* A trigger just needs to represent a valid bit position */
trig_valid(struct bcm_clk_trig * trig,const char * field_name,const char * clock_name)392 static bool trig_valid(struct bcm_clk_trig *trig, const char *field_name,
393 			const char *clock_name)
394 {
395 	return bit_posn_valid(trig->bit, field_name, clock_name);
396 }
397 
398 /* Determine whether the set of peripheral clock registers are valid. */
399 static bool
peri_clk_data_valid(struct kona_clk * bcm_clk)400 peri_clk_data_valid(struct kona_clk *bcm_clk)
401 {
402 	struct peri_clk_data *peri;
403 	struct bcm_clk_policy *policy;
404 	struct bcm_clk_gate *gate;
405 	struct bcm_clk_hyst *hyst;
406 	struct bcm_clk_sel *sel;
407 	struct bcm_clk_div *div;
408 	struct bcm_clk_div *pre_div;
409 	struct bcm_clk_trig *trig;
410 	const char *name;
411 
412 	BUG_ON(bcm_clk->type != bcm_clk_peri);
413 
414 	/*
415 	 * First validate register offsets.  This is the only place
416 	 * where we need something from the ccu, so we do these
417 	 * together.
418 	 */
419 	if (!peri_clk_data_offsets_valid(bcm_clk))
420 		return false;
421 
422 	peri = bcm_clk->u.peri;
423 	name = bcm_clk->init_data.name;
424 
425 	policy = &peri->policy;
426 	if (policy_exists(policy) && !policy_valid(policy, name))
427 		return false;
428 
429 	gate = &peri->gate;
430 	if (gate_exists(gate) && !gate_valid(gate, "gate", name))
431 		return false;
432 
433 	hyst = &peri->hyst;
434 	if (hyst_exists(hyst) && !hyst_valid(hyst, name))
435 		return false;
436 
437 	sel = &peri->sel;
438 	if (selector_exists(sel)) {
439 		if (!sel_valid(sel, "selector", name))
440 			return false;
441 
442 	} else if (sel->parent_count > 1) {
443 		pr_err("%s: multiple parents but no selector for %s\n",
444 			__func__, name);
445 
446 		return false;
447 	}
448 
449 	div = &peri->div;
450 	pre_div = &peri->pre_div;
451 	if (divider_exists(div)) {
452 		if (!div_valid(div, "divider", name))
453 			return false;
454 
455 		if (divider_exists(pre_div))
456 			if (!div_valid(pre_div, "pre-divider", name))
457 				return false;
458 	} else if (divider_exists(pre_div)) {
459 		pr_err("%s: pre-divider but no divider for %s\n", __func__,
460 			name);
461 		return false;
462 	}
463 
464 	trig = &peri->trig;
465 	if (trigger_exists(trig)) {
466 		if (!trig_valid(trig, "trigger", name))
467 			return false;
468 
469 		if (trigger_exists(&peri->pre_trig)) {
470 			if (!trig_valid(trig, "pre-trigger", name)) {
471 				return false;
472 			}
473 		}
474 		if (!clk_requires_trigger(bcm_clk)) {
475 			pr_warn("%s: ignoring trigger for %s (not needed)\n",
476 				__func__, name);
477 			trigger_clear_exists(trig);
478 		}
479 	} else if (trigger_exists(&peri->pre_trig)) {
480 		pr_err("%s: pre-trigger but no trigger for %s\n", __func__,
481 			name);
482 		return false;
483 	} else if (clk_requires_trigger(bcm_clk)) {
484 		pr_err("%s: required trigger missing for %s\n", __func__,
485 			name);
486 		return false;
487 	}
488 
489 	return kona_dividers_valid(bcm_clk);
490 }
491 
kona_clk_valid(struct kona_clk * bcm_clk)492 static bool kona_clk_valid(struct kona_clk *bcm_clk)
493 {
494 	switch (bcm_clk->type) {
495 	case bcm_clk_peri:
496 		if (!peri_clk_data_valid(bcm_clk))
497 			return false;
498 		break;
499 	default:
500 		pr_err("%s: unrecognized clock type (%d)\n", __func__,
501 			(int)bcm_clk->type);
502 		return false;
503 	}
504 	return true;
505 }
506 
507 /*
508  * Scan an array of parent clock names to determine whether there
509  * are any entries containing BAD_CLK_NAME.  Such entries are
510  * placeholders for non-supported clocks.  Keep track of the
511  * position of each clock name in the original array.
512  *
513  * Allocates an array of pointers to hold the names of all
514  * non-null entries in the original array, and returns a pointer to
515  * that array in *names.  This will be used for registering the
516  * clock with the common clock code.  On successful return,
517  * *count indicates how many entries are in that names array.
518  *
519  * If there is more than one entry in the resulting names array,
520  * another array is allocated to record the parent selector value
521  * for each (defined) parent clock.  This is the value that
522  * represents this parent clock in the clock's source selector
523  * register.  The position of the clock in the original parent array
524  * defines that selector value.  The number of entries in this array
525  * is the same as the number of entries in the parent names array.
526  *
527  * The array of selector values is returned.  If the clock has no
528  * parents, no selector is required and a null pointer is returned.
529  *
530  * Returns a null pointer if the clock names array supplied was
531  * null.  (This is not an error.)
532  *
533  * Returns a pointer-coded error if an error occurs.
534  */
parent_process(const char * clocks[],u32 * count,const char *** names)535 static u32 *parent_process(const char *clocks[],
536 			u32 *count, const char ***names)
537 {
538 	static const char **parent_names;
539 	static u32 *parent_sel;
540 	const char **clock;
541 	u32 parent_count;
542 	u32 bad_count = 0;
543 	u32 orig_count;
544 	u32 i;
545 	u32 j;
546 
547 	*count = 0;	/* In case of early return */
548 	*names = NULL;
549 	if (!clocks)
550 		return NULL;
551 
552 	/*
553 	 * Count the number of names in the null-terminated array,
554 	 * and find out how many of those are actually clock names.
555 	 */
556 	for (clock = clocks; *clock; clock++)
557 		if (*clock == BAD_CLK_NAME)
558 			bad_count++;
559 	orig_count = (u32)(clock - clocks);
560 	parent_count = orig_count - bad_count;
561 
562 	/* If all clocks are unsupported, we treat it as no clock */
563 	if (!parent_count)
564 		return NULL;
565 
566 	/* Avoid exceeding our parent clock limit */
567 	if (parent_count > PARENT_COUNT_MAX) {
568 		pr_err("%s: too many parents (%u > %u)\n", __func__,
569 			parent_count, PARENT_COUNT_MAX);
570 		return ERR_PTR(-EINVAL);
571 	}
572 
573 	/*
574 	 * There is one parent name for each defined parent clock.
575 	 * We also maintain an array containing the selector value
576 	 * for each defined clock.  If there's only one clock, the
577 	 * selector is not required, but we allocate space for the
578 	 * array anyway to keep things simple.
579 	 */
580 	parent_names = kmalloc_array(parent_count, sizeof(*parent_names),
581 			       GFP_KERNEL);
582 	if (!parent_names)
583 		return ERR_PTR(-ENOMEM);
584 
585 	/* There is at least one parent, so allocate a selector array */
586 	parent_sel = kmalloc_array(parent_count, sizeof(*parent_sel),
587 				   GFP_KERNEL);
588 	if (!parent_sel) {
589 		kfree(parent_names);
590 
591 		return ERR_PTR(-ENOMEM);
592 	}
593 
594 	/* Now fill in the parent names and selector arrays */
595 	for (i = 0, j = 0; i < orig_count; i++) {
596 		if (clocks[i] != BAD_CLK_NAME) {
597 			parent_names[j] = clocks[i];
598 			parent_sel[j] = i;
599 			j++;
600 		}
601 	}
602 	*names = parent_names;
603 	*count = parent_count;
604 
605 	return parent_sel;
606 }
607 
608 static int
clk_sel_setup(const char ** clocks,struct bcm_clk_sel * sel,struct clk_init_data * init_data)609 clk_sel_setup(const char **clocks, struct bcm_clk_sel *sel,
610 		struct clk_init_data *init_data)
611 {
612 	const char **parent_names = NULL;
613 	u32 parent_count = 0;
614 	u32 *parent_sel;
615 
616 	/*
617 	 * If a peripheral clock has multiple parents, the value
618 	 * used by the hardware to select that parent is represented
619 	 * by the parent clock's position in the "clocks" list.  Some
620 	 * values don't have defined or supported clocks; these will
621 	 * have BAD_CLK_NAME entries in the parents[] array.  The
622 	 * list is terminated by a NULL entry.
623 	 *
624 	 * We need to supply (only) the names of defined parent
625 	 * clocks when registering a clock though, so we use an
626 	 * array of parent selector values to map between the
627 	 * indexes the common clock code uses and the selector
628 	 * values we need.
629 	 */
630 	parent_sel = parent_process(clocks, &parent_count, &parent_names);
631 	if (IS_ERR(parent_sel)) {
632 		int ret = PTR_ERR(parent_sel);
633 
634 		pr_err("%s: error processing parent clocks for %s (%d)\n",
635 			__func__, init_data->name, ret);
636 
637 		return ret;
638 	}
639 
640 	init_data->parent_names = parent_names;
641 	init_data->num_parents = parent_count;
642 
643 	sel->parent_count = parent_count;
644 	sel->parent_sel = parent_sel;
645 
646 	return 0;
647 }
648 
clk_sel_teardown(struct bcm_clk_sel * sel,struct clk_init_data * init_data)649 static void clk_sel_teardown(struct bcm_clk_sel *sel,
650 		struct clk_init_data *init_data)
651 {
652 	kfree(sel->parent_sel);
653 	sel->parent_sel = NULL;
654 	sel->parent_count = 0;
655 
656 	init_data->num_parents = 0;
657 	kfree(init_data->parent_names);
658 	init_data->parent_names = NULL;
659 }
660 
peri_clk_teardown(struct peri_clk_data * data,struct clk_init_data * init_data)661 static void peri_clk_teardown(struct peri_clk_data *data,
662 				struct clk_init_data *init_data)
663 {
664 	clk_sel_teardown(&data->sel, init_data);
665 }
666 
667 /*
668  * Caller is responsible for freeing the parent_names[] and
669  * parent_sel[] arrays in the peripheral clock's "data" structure
670  * that can be assigned if the clock has one or more parent clocks
671  * associated with it.
672  */
673 static int
peri_clk_setup(struct peri_clk_data * data,struct clk_init_data * init_data)674 peri_clk_setup(struct peri_clk_data *data, struct clk_init_data *init_data)
675 {
676 	init_data->flags = CLK_IGNORE_UNUSED;
677 
678 	return clk_sel_setup(data->clocks, &data->sel, init_data);
679 }
680 
bcm_clk_teardown(struct kona_clk * bcm_clk)681 static void bcm_clk_teardown(struct kona_clk *bcm_clk)
682 {
683 	switch (bcm_clk->type) {
684 	case bcm_clk_peri:
685 		peri_clk_teardown(bcm_clk->u.data, &bcm_clk->init_data);
686 		break;
687 	default:
688 		break;
689 	}
690 	bcm_clk->u.data = NULL;
691 	bcm_clk->type = bcm_clk_none;
692 }
693 
kona_clk_teardown(struct clk_hw * hw)694 static void kona_clk_teardown(struct clk_hw *hw)
695 {
696 	struct kona_clk *bcm_clk;
697 
698 	if (!hw)
699 		return;
700 
701 	clk_hw_unregister(hw);
702 
703 	bcm_clk = to_kona_clk(hw);
704 	bcm_clk_teardown(bcm_clk);
705 }
706 
kona_clk_setup(struct kona_clk * bcm_clk)707 static int kona_clk_setup(struct kona_clk *bcm_clk)
708 {
709 	int ret;
710 	struct clk_init_data *init_data = &bcm_clk->init_data;
711 
712 	switch (bcm_clk->type) {
713 	case bcm_clk_peri:
714 		ret = peri_clk_setup(bcm_clk->u.data, init_data);
715 		if (ret)
716 			return ret;
717 		break;
718 	default:
719 		pr_err("%s: clock type %d invalid for %s\n", __func__,
720 			(int)bcm_clk->type, init_data->name);
721 		return -EINVAL;
722 	}
723 
724 	/* Make sure everything makes sense before we set it up */
725 	if (!kona_clk_valid(bcm_clk)) {
726 		pr_err("%s: clock data invalid for %s\n", __func__,
727 			init_data->name);
728 		ret = -EINVAL;
729 		goto out_teardown;
730 	}
731 
732 	bcm_clk->hw.init = init_data;
733 	ret = clk_hw_register(NULL, &bcm_clk->hw);
734 	if (ret) {
735 		pr_err("%s: error registering clock %s (%d)\n", __func__,
736 			init_data->name, ret);
737 		goto out_teardown;
738 	}
739 
740 	return 0;
741 out_teardown:
742 	bcm_clk_teardown(bcm_clk);
743 
744 	return ret;
745 }
746 
ccu_clks_teardown(struct ccu_data * ccu)747 static void ccu_clks_teardown(struct ccu_data *ccu)
748 {
749 	u32 i;
750 
751 	for (i = 0; i < ccu->clk_num; i++)
752 		kona_clk_teardown(&ccu->kona_clks[i].hw);
753 }
754 
kona_ccu_teardown(struct ccu_data * ccu)755 static void kona_ccu_teardown(struct ccu_data *ccu)
756 {
757 	if (!ccu->base)
758 		return;
759 
760 	of_clk_del_provider(ccu->node);	/* safe if never added */
761 	ccu_clks_teardown(ccu);
762 	of_node_put(ccu->node);
763 	ccu->node = NULL;
764 	iounmap(ccu->base);
765 	ccu->base = NULL;
766 }
767 
ccu_data_valid(struct ccu_data * ccu)768 static bool ccu_data_valid(struct ccu_data *ccu)
769 {
770 	struct ccu_policy *ccu_policy;
771 
772 	if (!ccu_data_offsets_valid(ccu))
773 		return false;
774 
775 	ccu_policy = &ccu->policy;
776 	if (ccu_policy_exists(ccu_policy))
777 		if (!ccu_policy_valid(ccu_policy, ccu->name))
778 			return false;
779 
780 	return true;
781 }
782 
783 static struct clk_hw *
of_clk_kona_onecell_get(struct of_phandle_args * clkspec,void * data)784 of_clk_kona_onecell_get(struct of_phandle_args *clkspec, void *data)
785 {
786 	struct ccu_data *ccu = data;
787 	unsigned int idx = clkspec->args[0];
788 
789 	if (idx >= ccu->clk_num) {
790 		pr_err("%s: invalid index %u\n", __func__, idx);
791 		return ERR_PTR(-EINVAL);
792 	}
793 
794 	return &ccu->kona_clks[idx].hw;
795 }
796 
797 /*
798  * Set up a CCU.  Call the provided ccu_clks_setup callback to
799  * initialize the array of clocks provided by the CCU.
800  */
kona_dt_ccu_setup(struct ccu_data * ccu,struct device_node * node)801 void __init kona_dt_ccu_setup(struct ccu_data *ccu,
802 			struct device_node *node)
803 {
804 	struct resource res = { 0 };
805 	resource_size_t range;
806 	unsigned int i;
807 	int ret;
808 
809 	ret = of_address_to_resource(node, 0, &res);
810 	if (ret) {
811 		pr_err("%s: no valid CCU registers found for %pOFn\n", __func__,
812 			node);
813 		goto out_err;
814 	}
815 
816 	range = resource_size(&res);
817 	if (range > (resource_size_t)U32_MAX) {
818 		pr_err("%s: address range too large for %pOFn\n", __func__,
819 			node);
820 		goto out_err;
821 	}
822 
823 	ccu->range = (u32)range;
824 
825 	if (!ccu_data_valid(ccu)) {
826 		pr_err("%s: ccu data not valid for %pOFn\n", __func__, node);
827 		goto out_err;
828 	}
829 
830 	ccu->base = ioremap(res.start, ccu->range);
831 	if (!ccu->base) {
832 		pr_err("%s: unable to map CCU registers for %pOFn\n", __func__,
833 			node);
834 		goto out_err;
835 	}
836 	ccu->node = of_node_get(node);
837 
838 	/*
839 	 * Set up each defined kona clock and save the result in
840 	 * the clock framework clock array (in ccu->data).  Then
841 	 * register as a provider for these clocks.
842 	 */
843 	for (i = 0; i < ccu->clk_num; i++) {
844 		if (!ccu->kona_clks[i].ccu)
845 			continue;
846 		kona_clk_setup(&ccu->kona_clks[i]);
847 	}
848 
849 	ret = of_clk_add_hw_provider(node, of_clk_kona_onecell_get, ccu);
850 	if (ret) {
851 		pr_err("%s: error adding ccu %pOFn as provider (%d)\n", __func__,
852 				node, ret);
853 		goto out_err;
854 	}
855 
856 	if (!kona_ccu_init(ccu))
857 		pr_err("Broadcom %pOFn initialization had errors\n", node);
858 
859 	return;
860 out_err:
861 	kona_ccu_teardown(ccu);
862 	pr_err("Broadcom %pOFn setup aborted\n", node);
863 }
864