xref: /rk3399_ARM-atf/drivers/nxp/clk/s32cc/s32cc_clk_drv.c (revision 7f152ea6856c7780424ec3e92b181d805a314f43)
1 /*
2  * Copyright 2024 NXP
3  *
4  * SPDX-License-Identifier: BSD-3-Clause
5  */
6 #include <errno.h>
7 
8 #include <s32cc-clk-regs.h>
9 
10 #include <common/debug.h>
11 #include <drivers/clk.h>
12 #include <lib/mmio.h>
13 #include <s32cc-clk-ids.h>
14 #include <s32cc-clk-modules.h>
15 #include <s32cc-clk-utils.h>
16 
17 #define MAX_STACK_DEPTH		(40U)
18 
19 /* This is used for floating-point precision calculations. */
20 #define FP_PRECISION		(100000000UL)
21 
22 struct s32cc_clk_drv {
23 	uintptr_t fxosc_base;
24 	uintptr_t armpll_base;
25 	uintptr_t periphpll_base;
26 	uintptr_t armdfs_base;
27 	uintptr_t cgm0_base;
28 	uintptr_t cgm1_base;
29 };
30 
31 static int update_stack_depth(unsigned int *depth)
32 {
33 	if (*depth == 0U) {
34 		return -ENOMEM;
35 	}
36 
37 	(*depth)--;
38 	return 0;
39 }
40 
41 static struct s32cc_clk_drv *get_drv(void)
42 {
43 	static struct s32cc_clk_drv driver = {
44 		.fxosc_base = FXOSC_BASE_ADDR,
45 		.armpll_base = ARMPLL_BASE_ADDR,
46 		.periphpll_base = PERIPHPLL_BASE_ADDR,
47 		.armdfs_base = ARM_DFS_BASE_ADDR,
48 		.cgm0_base = CGM0_BASE_ADDR,
49 		.cgm1_base = CGM1_BASE_ADDR,
50 	};
51 
52 	return &driver;
53 }
54 
55 static int enable_module(struct s32cc_clk_obj *module,
56 			 const struct s32cc_clk_drv *drv,
57 			 unsigned int depth);
58 
59 static struct s32cc_clk_obj *get_clk_parent(const struct s32cc_clk_obj *module)
60 {
61 	const struct s32cc_clk *clk = s32cc_obj2clk(module);
62 
63 	if (clk->module != NULL) {
64 		return clk->module;
65 	}
66 
67 	if (clk->pclock != NULL) {
68 		return &clk->pclock->desc;
69 	}
70 
71 	return NULL;
72 }
73 
74 static int get_base_addr(enum s32cc_clk_source id, const struct s32cc_clk_drv *drv,
75 			 uintptr_t *base)
76 {
77 	int ret = 0;
78 
79 	switch (id) {
80 	case S32CC_FXOSC:
81 		*base = drv->fxosc_base;
82 		break;
83 	case S32CC_ARM_PLL:
84 		*base = drv->armpll_base;
85 		break;
86 	case S32CC_PERIPH_PLL:
87 		*base = drv->periphpll_base;
88 		break;
89 	case S32CC_ARM_DFS:
90 		*base = drv->armdfs_base;
91 		break;
92 	case S32CC_CGM0:
93 		*base = drv->cgm0_base;
94 		break;
95 	case S32CC_CGM1:
96 		*base = drv->cgm1_base;
97 		break;
98 	case S32CC_FIRC:
99 		break;
100 	case S32CC_SIRC:
101 		break;
102 	default:
103 		ret = -EINVAL;
104 		break;
105 	}
106 
107 	if (ret != 0) {
108 		ERROR("Unknown clock source id: %u\n", id);
109 	}
110 
111 	return ret;
112 }
113 
114 static void enable_fxosc(const struct s32cc_clk_drv *drv)
115 {
116 	uintptr_t fxosc_base = drv->fxosc_base;
117 	uint32_t ctrl;
118 
119 	ctrl = mmio_read_32(FXOSC_CTRL(fxosc_base));
120 	if ((ctrl & FXOSC_CTRL_OSCON) != U(0)) {
121 		return;
122 	}
123 
124 	ctrl = FXOSC_CTRL_COMP_EN;
125 	ctrl &= ~FXOSC_CTRL_OSC_BYP;
126 	ctrl |= FXOSC_CTRL_EOCV(0x1);
127 	ctrl |= FXOSC_CTRL_GM_SEL(0x7);
128 	mmio_write_32(FXOSC_CTRL(fxosc_base), ctrl);
129 
130 	/* Switch ON the crystal oscillator. */
131 	mmio_setbits_32(FXOSC_CTRL(fxosc_base), FXOSC_CTRL_OSCON);
132 
133 	/* Wait until the clock is stable. */
134 	while ((mmio_read_32(FXOSC_STAT(fxosc_base)) & FXOSC_STAT_OSC_STAT) == U(0)) {
135 	}
136 }
137 
138 static int enable_osc(struct s32cc_clk_obj *module,
139 		      const struct s32cc_clk_drv *drv,
140 		      unsigned int depth)
141 {
142 	const struct s32cc_osc *osc = s32cc_obj2osc(module);
143 	int ret = 0;
144 
145 	ret = update_stack_depth(&depth);
146 	if (ret != 0) {
147 		return ret;
148 	}
149 
150 	switch (osc->source) {
151 	case S32CC_FXOSC:
152 		enable_fxosc(drv);
153 		break;
154 	/* FIRC and SIRC oscillators are enabled by default */
155 	case S32CC_FIRC:
156 		break;
157 	case S32CC_SIRC:
158 		break;
159 	default:
160 		ERROR("Invalid oscillator %d\n", osc->source);
161 		ret = -EINVAL;
162 		break;
163 	};
164 
165 	return ret;
166 }
167 
168 static struct s32cc_clk_obj *get_pll_parent(const struct s32cc_clk_obj *module)
169 {
170 	const struct s32cc_pll *pll = s32cc_obj2pll(module);
171 
172 	if (pll->source == NULL) {
173 		ERROR("Failed to identify PLL's parent\n");
174 	}
175 
176 	return pll->source;
177 }
178 
179 static int get_pll_mfi_mfn(unsigned long pll_vco, unsigned long ref_freq,
180 			   uint32_t *mfi, uint32_t *mfn)
181 
182 {
183 	unsigned long vco;
184 	unsigned long mfn64;
185 
186 	/* FRAC-N mode */
187 	*mfi = (uint32_t)(pll_vco / ref_freq);
188 
189 	/* MFN formula : (double)(pll_vco % ref_freq) / ref_freq * 18432.0 */
190 	mfn64 = pll_vco % ref_freq;
191 	mfn64 *= FP_PRECISION;
192 	mfn64 /= ref_freq;
193 	mfn64 *= 18432UL;
194 	mfn64 /= FP_PRECISION;
195 
196 	if (mfn64 > UINT32_MAX) {
197 		return -EINVAL;
198 	}
199 
200 	*mfn = (uint32_t)mfn64;
201 
202 	vco = ((unsigned long)*mfn * FP_PRECISION) / 18432UL;
203 	vco += (unsigned long)*mfi * FP_PRECISION;
204 	vco *= ref_freq;
205 	vco /= FP_PRECISION;
206 
207 	if (vco != pll_vco) {
208 		ERROR("Failed to find MFI and MFN settings for PLL freq %lu. Nearest freq = %lu\n",
209 		      pll_vco, vco);
210 		return -EINVAL;
211 	}
212 
213 	return 0;
214 }
215 
216 static struct s32cc_clkmux *get_pll_mux(const struct s32cc_pll *pll)
217 {
218 	const struct s32cc_clk_obj *source = pll->source;
219 	const struct s32cc_clk *clk;
220 
221 	if (source == NULL) {
222 		ERROR("Failed to identify PLL's parent\n");
223 		return NULL;
224 	}
225 
226 	if (source->type != s32cc_clk_t) {
227 		ERROR("The parent of the PLL isn't a clock\n");
228 		return NULL;
229 	}
230 
231 	clk = s32cc_obj2clk(source);
232 
233 	if (clk->module == NULL) {
234 		ERROR("The clock isn't connected to a module\n");
235 		return NULL;
236 	}
237 
238 	source = clk->module;
239 
240 	if ((source->type != s32cc_clkmux_t) &&
241 	    (source->type != s32cc_shared_clkmux_t)) {
242 		ERROR("The parent of the PLL isn't a MUX\n");
243 		return NULL;
244 	}
245 
246 	return s32cc_obj2clkmux(source);
247 }
248 
249 static void disable_odiv(uintptr_t pll_addr, uint32_t div_index)
250 {
251 	mmio_clrbits_32(PLLDIG_PLLODIV(pll_addr, div_index), PLLDIG_PLLODIV_DE);
252 }
253 
254 static void enable_odiv(uintptr_t pll_addr, uint32_t div_index)
255 {
256 	mmio_setbits_32(PLLDIG_PLLODIV(pll_addr, div_index), PLLDIG_PLLODIV_DE);
257 }
258 
259 static void disable_odivs(uintptr_t pll_addr, uint32_t ndivs)
260 {
261 	uint32_t i;
262 
263 	for (i = 0; i < ndivs; i++) {
264 		disable_odiv(pll_addr, i);
265 	}
266 }
267 
268 static void enable_pll_hw(uintptr_t pll_addr)
269 {
270 	/* Enable the PLL. */
271 	mmio_write_32(PLLDIG_PLLCR(pll_addr), 0x0);
272 
273 	/* Poll until PLL acquires lock. */
274 	while ((mmio_read_32(PLLDIG_PLLSR(pll_addr)) & PLLDIG_PLLSR_LOCK) == 0U) {
275 	}
276 }
277 
278 static void disable_pll_hw(uintptr_t pll_addr)
279 {
280 	mmio_write_32(PLLDIG_PLLCR(pll_addr), PLLDIG_PLLCR_PLLPD);
281 }
282 
283 static int program_pll(const struct s32cc_pll *pll, uintptr_t pll_addr,
284 		       const struct s32cc_clk_drv *drv, uint32_t sclk_id,
285 		       unsigned long sclk_freq)
286 {
287 	uint32_t rdiv = 1, mfi, mfn;
288 	int ret;
289 
290 	ret = get_pll_mfi_mfn(pll->vco_freq, sclk_freq, &mfi, &mfn);
291 	if (ret != 0) {
292 		return -EINVAL;
293 	}
294 
295 	/* Disable ODIVs*/
296 	disable_odivs(pll_addr, pll->ndividers);
297 
298 	/* Disable PLL */
299 	disable_pll_hw(pll_addr);
300 
301 	/* Program PLLCLKMUX */
302 	mmio_write_32(PLLDIG_PLLCLKMUX(pll_addr), sclk_id);
303 
304 	/* Program VCO */
305 	mmio_clrsetbits_32(PLLDIG_PLLDV(pll_addr),
306 			   PLLDIG_PLLDV_RDIV_MASK | PLLDIG_PLLDV_MFI_MASK,
307 			   PLLDIG_PLLDV_RDIV_SET(rdiv) | PLLDIG_PLLDV_MFI(mfi));
308 
309 	mmio_write_32(PLLDIG_PLLFD(pll_addr),
310 		      PLLDIG_PLLFD_MFN_SET(mfn) | PLLDIG_PLLFD_SMDEN);
311 
312 	enable_pll_hw(pll_addr);
313 
314 	return ret;
315 }
316 
317 static int enable_pll(struct s32cc_clk_obj *module,
318 		      const struct s32cc_clk_drv *drv,
319 		      unsigned int depth)
320 {
321 	const struct s32cc_pll *pll = s32cc_obj2pll(module);
322 	const struct s32cc_clkmux *mux;
323 	uintptr_t pll_addr = UL(0x0);
324 	unsigned long sclk_freq;
325 	uint32_t sclk_id;
326 	int ret;
327 
328 	ret = update_stack_depth(&depth);
329 	if (ret != 0) {
330 		return ret;
331 	}
332 
333 	mux = get_pll_mux(pll);
334 	if (mux == NULL) {
335 		return -EINVAL;
336 	}
337 
338 	if (pll->instance != mux->module) {
339 		ERROR("MUX type is not in sync with PLL ID\n");
340 		return -EINVAL;
341 	}
342 
343 	ret = get_base_addr(pll->instance, drv, &pll_addr);
344 	if (ret != 0) {
345 		ERROR("Failed to detect PLL instance\n");
346 		return ret;
347 	}
348 
349 	switch (mux->source_id) {
350 	case S32CC_CLK_FIRC:
351 		sclk_freq = 48U * MHZ;
352 		sclk_id = 0;
353 		break;
354 	case S32CC_CLK_FXOSC:
355 		sclk_freq = 40U * MHZ;
356 		sclk_id = 1;
357 		break;
358 	default:
359 		ERROR("Invalid source selection for PLL 0x%lx\n",
360 		      pll_addr);
361 		return -EINVAL;
362 	};
363 
364 	return program_pll(pll, pll_addr, drv, sclk_id, sclk_freq);
365 }
366 
367 static inline struct s32cc_pll *get_div_pll(const struct s32cc_pll_out_div *pdiv)
368 {
369 	const struct s32cc_clk_obj *parent;
370 
371 	parent = pdiv->parent;
372 	if (parent == NULL) {
373 		ERROR("Failed to identify PLL divider's parent\n");
374 		return NULL;
375 	}
376 
377 	if (parent->type != s32cc_pll_t) {
378 		ERROR("The parent of the divider is not a PLL instance\n");
379 		return NULL;
380 	}
381 
382 	return s32cc_obj2pll(parent);
383 }
384 
385 static void config_pll_out_div(uintptr_t pll_addr, uint32_t div_index, uint32_t dc)
386 {
387 	uint32_t pllodiv;
388 	uint32_t pdiv;
389 
390 	pllodiv = mmio_read_32(PLLDIG_PLLODIV(pll_addr, div_index));
391 	pdiv = PLLDIG_PLLODIV_DIV(pllodiv);
392 
393 	if (((pdiv + 1U) == dc) && ((pllodiv & PLLDIG_PLLODIV_DE) != 0U)) {
394 		return;
395 	}
396 
397 	if ((pllodiv & PLLDIG_PLLODIV_DE) != 0U) {
398 		disable_odiv(pll_addr, div_index);
399 	}
400 
401 	pllodiv = PLLDIG_PLLODIV_DIV_SET(dc - 1U);
402 	mmio_write_32(PLLDIG_PLLODIV(pll_addr, div_index), pllodiv);
403 
404 	enable_odiv(pll_addr, div_index);
405 }
406 
407 static struct s32cc_clk_obj *get_pll_div_parent(const struct s32cc_clk_obj *module)
408 {
409 	const struct s32cc_pll_out_div *pdiv = s32cc_obj2plldiv(module);
410 
411 	if (pdiv->parent == NULL) {
412 		ERROR("Failed to identify PLL DIV's parent\n");
413 	}
414 
415 	return pdiv->parent;
416 }
417 
418 static int enable_pll_div(struct s32cc_clk_obj *module,
419 			  const struct s32cc_clk_drv *drv,
420 			  unsigned int depth)
421 {
422 	const struct s32cc_pll_out_div *pdiv = s32cc_obj2plldiv(module);
423 	uintptr_t pll_addr = 0x0ULL;
424 	const struct s32cc_pll *pll;
425 	uint32_t dc;
426 	int ret;
427 
428 	ret = update_stack_depth(&depth);
429 	if (ret != 0) {
430 		return ret;
431 	}
432 
433 	pll = get_div_pll(pdiv);
434 	if (pll == NULL) {
435 		ERROR("The parent of the PLL DIV is invalid\n");
436 		return 0;
437 	}
438 
439 	ret = get_base_addr(pll->instance, drv, &pll_addr);
440 	if (ret != 0) {
441 		ERROR("Failed to detect PLL instance\n");
442 		return -EINVAL;
443 	}
444 
445 	dc = (uint32_t)(pll->vco_freq / pdiv->freq);
446 
447 	config_pll_out_div(pll_addr, pdiv->index, dc);
448 
449 	return 0;
450 }
451 
452 static int cgm_mux_clk_config(uintptr_t cgm_addr, uint32_t mux, uint32_t source,
453 			      bool safe_clk)
454 {
455 	uint32_t css, csc;
456 
457 	css = mmio_read_32(CGM_MUXn_CSS(cgm_addr, mux));
458 
459 	/* Already configured */
460 	if ((MC_CGM_MUXn_CSS_SELSTAT(css) == source) &&
461 	    (MC_CGM_MUXn_CSS_SWTRG(css) == MC_CGM_MUXn_CSS_SWTRG_SUCCESS) &&
462 	    ((css & MC_CGM_MUXn_CSS_SWIP) == 0U) && !safe_clk) {
463 		return 0;
464 	}
465 
466 	/* Ongoing clock switch? */
467 	while ((mmio_read_32(CGM_MUXn_CSS(cgm_addr, mux)) &
468 		MC_CGM_MUXn_CSS_SWIP) != 0U) {
469 	}
470 
471 	csc = mmio_read_32(CGM_MUXn_CSC(cgm_addr, mux));
472 
473 	/* Clear previous source. */
474 	csc &= ~(MC_CGM_MUXn_CSC_SELCTL_MASK);
475 
476 	if (!safe_clk) {
477 		/* Select the clock source and trigger the clock switch. */
478 		csc |= MC_CGM_MUXn_CSC_SELCTL(source) | MC_CGM_MUXn_CSC_CLK_SW;
479 	} else {
480 		/* Switch to safe clock */
481 		csc |= MC_CGM_MUXn_CSC_SAFE_SW;
482 	}
483 
484 	mmio_write_32(CGM_MUXn_CSC(cgm_addr, mux), csc);
485 
486 	/* Wait for configuration bit to auto-clear. */
487 	while ((mmio_read_32(CGM_MUXn_CSC(cgm_addr, mux)) &
488 		MC_CGM_MUXn_CSC_CLK_SW) != 0U) {
489 	}
490 
491 	/* Is the clock switch completed? */
492 	while ((mmio_read_32(CGM_MUXn_CSS(cgm_addr, mux)) &
493 		MC_CGM_MUXn_CSS_SWIP) != 0U) {
494 	}
495 
496 	/*
497 	 * Check if the switch succeeded.
498 	 * Check switch trigger cause and the source.
499 	 */
500 	css = mmio_read_32(CGM_MUXn_CSS(cgm_addr, mux));
501 	if (!safe_clk) {
502 		if ((MC_CGM_MUXn_CSS_SWTRG(css) == MC_CGM_MUXn_CSS_SWTRG_SUCCESS) &&
503 		    (MC_CGM_MUXn_CSS_SELSTAT(css) == source)) {
504 			return 0;
505 		}
506 
507 		ERROR("Failed to change the source of mux %" PRIu32 " to %" PRIu32 " (CGM=%lu)\n",
508 		      mux, source, cgm_addr);
509 	} else {
510 		if (((MC_CGM_MUXn_CSS_SWTRG(css) == MC_CGM_MUXn_CSS_SWTRG_SAFE_CLK) ||
511 		     (MC_CGM_MUXn_CSS_SWTRG(css) == MC_CGM_MUXn_CSS_SWTRG_SAFE_CLK_INACTIVE)) &&
512 		     ((MC_CGM_MUXn_CSS_SAFE_SW & css) != 0U)) {
513 			return 0;
514 		}
515 
516 		ERROR("The switch of mux %" PRIu32 " (CGM=%lu) to safe clock failed\n",
517 		      mux, cgm_addr);
518 	}
519 
520 	return -EINVAL;
521 }
522 
523 static int enable_cgm_mux(const struct s32cc_clkmux *mux,
524 			  const struct s32cc_clk_drv *drv)
525 {
526 	uintptr_t cgm_addr = UL(0x0);
527 	uint32_t mux_hw_clk;
528 	int ret;
529 
530 	ret = get_base_addr(mux->module, drv, &cgm_addr);
531 	if (ret != 0) {
532 		return ret;
533 	}
534 
535 	mux_hw_clk = (uint32_t)S32CC_CLK_ID(mux->source_id);
536 
537 	return cgm_mux_clk_config(cgm_addr, mux->index,
538 				  mux_hw_clk, false);
539 }
540 
541 static struct s32cc_clk_obj *get_mux_parent(const struct s32cc_clk_obj *module)
542 {
543 	const struct s32cc_clkmux *mux = s32cc_obj2clkmux(module);
544 	struct s32cc_clk *clk;
545 
546 	if (mux == NULL) {
547 		return NULL;
548 	}
549 
550 	clk = s32cc_get_arch_clk(mux->source_id);
551 	if (clk == NULL) {
552 		ERROR("Invalid parent (%lu) for mux %" PRIu8 "\n",
553 		      mux->source_id, mux->index);
554 		return NULL;
555 	}
556 
557 	return &clk->desc;
558 }
559 
560 static int enable_mux(struct s32cc_clk_obj *module,
561 		      const struct s32cc_clk_drv *drv,
562 		      unsigned int depth)
563 {
564 	const struct s32cc_clkmux *mux = s32cc_obj2clkmux(module);
565 	const struct s32cc_clk *clk;
566 	int ret = 0;
567 
568 	ret = update_stack_depth(&depth);
569 	if (ret != 0) {
570 		return ret;
571 	}
572 
573 	if (mux == NULL) {
574 		return -EINVAL;
575 	}
576 
577 	clk = s32cc_get_arch_clk(mux->source_id);
578 	if (clk == NULL) {
579 		ERROR("Invalid parent (%lu) for mux %" PRIu8 "\n",
580 		      mux->source_id, mux->index);
581 		return -EINVAL;
582 	}
583 
584 	switch (mux->module) {
585 	/* PLL mux will be enabled by PLL setup */
586 	case S32CC_ARM_PLL:
587 	case S32CC_PERIPH_PLL:
588 		break;
589 	case S32CC_CGM1:
590 		ret = enable_cgm_mux(mux, drv);
591 		break;
592 	case S32CC_CGM0:
593 		ret = enable_cgm_mux(mux, drv);
594 		break;
595 	default:
596 		ERROR("Unknown mux parent type: %d\n", mux->module);
597 		ret = -EINVAL;
598 		break;
599 	};
600 
601 	return ret;
602 }
603 
604 static struct s32cc_clk_obj *get_dfs_parent(const struct s32cc_clk_obj *module)
605 {
606 	const struct s32cc_dfs *dfs = s32cc_obj2dfs(module);
607 
608 	if (dfs->parent == NULL) {
609 		ERROR("Failed to identify DFS's parent\n");
610 	}
611 
612 	return dfs->parent;
613 }
614 
615 static int enable_dfs(struct s32cc_clk_obj *module,
616 		      const struct s32cc_clk_drv *drv,
617 		      unsigned int depth)
618 {
619 	int ret = 0;
620 
621 	ret = update_stack_depth(&depth);
622 	if (ret != 0) {
623 		return ret;
624 	}
625 
626 	return 0;
627 }
628 
629 static struct s32cc_dfs *get_div_dfs(const struct s32cc_dfs_div *dfs_div)
630 {
631 	const struct s32cc_clk_obj *parent = dfs_div->parent;
632 
633 	if (parent->type != s32cc_dfs_t) {
634 		ERROR("DFS DIV doesn't have a DFS as parent\n");
635 		return NULL;
636 	}
637 
638 	return s32cc_obj2dfs(parent);
639 }
640 
641 static struct s32cc_pll *dfsdiv2pll(const struct s32cc_dfs_div *dfs_div)
642 {
643 	const struct s32cc_clk_obj *parent;
644 	const struct s32cc_dfs *dfs;
645 
646 	dfs = get_div_dfs(dfs_div);
647 	if (dfs == NULL) {
648 		return NULL;
649 	}
650 
651 	parent = dfs->parent;
652 	if (parent->type != s32cc_pll_t) {
653 		return NULL;
654 	}
655 
656 	return s32cc_obj2pll(parent);
657 }
658 
659 static int get_dfs_mfi_mfn(unsigned long dfs_freq, const struct s32cc_dfs_div *dfs_div,
660 			   uint32_t *mfi, uint32_t *mfn)
661 {
662 	uint64_t factor64, tmp64, ofreq;
663 	uint32_t factor32;
664 
665 	unsigned long in = dfs_freq;
666 	unsigned long out = dfs_div->freq;
667 
668 	/**
669 	 * factor = (IN / OUT) / 2
670 	 * MFI = integer(factor)
671 	 * MFN = (factor - MFI) * 36
672 	 */
673 	factor64 = ((((uint64_t)in) * FP_PRECISION) / ((uint64_t)out)) / 2ULL;
674 	tmp64 = factor64 / FP_PRECISION;
675 	if (tmp64 > UINT32_MAX) {
676 		return -EINVAL;
677 	}
678 
679 	factor32 = (uint32_t)tmp64;
680 	*mfi = factor32;
681 
682 	tmp64 = ((factor64 - ((uint64_t)*mfi * FP_PRECISION)) * 36UL) / FP_PRECISION;
683 	if (tmp64 > UINT32_MAX) {
684 		return -EINVAL;
685 	}
686 
687 	*mfn = (uint32_t)tmp64;
688 
689 	/* div_freq = in / (2 * (*mfi + *mfn / 36.0)) */
690 	factor64 = (((uint64_t)*mfn) * FP_PRECISION) / 36ULL;
691 	factor64 += ((uint64_t)*mfi) * FP_PRECISION;
692 	factor64 *= 2ULL;
693 	ofreq = (((uint64_t)in) * FP_PRECISION) / factor64;
694 
695 	if (ofreq != dfs_div->freq) {
696 		ERROR("Failed to find MFI and MFN settings for DFS DIV freq %lu\n",
697 		      dfs_div->freq);
698 		ERROR("Nearest freq = %" PRIx64 "\n", ofreq);
699 		return -EINVAL;
700 	}
701 
702 	return 0;
703 }
704 
705 static int init_dfs_port(uintptr_t dfs_addr, uint32_t port,
706 			 uint32_t mfi, uint32_t mfn)
707 {
708 	uint32_t portsr, portolsr;
709 	uint32_t mask, old_mfi, old_mfn;
710 	uint32_t dvport;
711 	bool init_dfs;
712 
713 	dvport = mmio_read_32(DFS_DVPORTn(dfs_addr, port));
714 
715 	old_mfi = DFS_DVPORTn_MFI(dvport);
716 	old_mfn = DFS_DVPORTn_MFN(dvport);
717 
718 	portsr = mmio_read_32(DFS_PORTSR(dfs_addr));
719 	portolsr = mmio_read_32(DFS_PORTOLSR(dfs_addr));
720 
721 	/* Skip configuration if it's not needed */
722 	if (((portsr & BIT_32(port)) != 0U) &&
723 	    ((portolsr & BIT_32(port)) == 0U) &&
724 	    (mfi == old_mfi) && (mfn == old_mfn)) {
725 		return 0;
726 	}
727 
728 	init_dfs = (portsr == 0U);
729 
730 	if (init_dfs) {
731 		mask = DFS_PORTRESET_MASK;
732 	} else {
733 		mask = DFS_PORTRESET_SET(BIT_32(port));
734 	}
735 
736 	mmio_write_32(DFS_PORTOLSR(dfs_addr), mask);
737 	mmio_write_32(DFS_PORTRESET(dfs_addr), mask);
738 
739 	while ((mmio_read_32(DFS_PORTSR(dfs_addr)) & mask) != 0U) {
740 	}
741 
742 	if (init_dfs) {
743 		mmio_write_32(DFS_CTL(dfs_addr), DFS_CTL_RESET);
744 	}
745 
746 	mmio_write_32(DFS_DVPORTn(dfs_addr, port),
747 		      DFS_DVPORTn_MFI_SET(mfi) | DFS_DVPORTn_MFN_SET(mfn));
748 
749 	if (init_dfs) {
750 		/* DFS clk enable programming */
751 		mmio_clrbits_32(DFS_CTL(dfs_addr), DFS_CTL_RESET);
752 	}
753 
754 	mmio_clrbits_32(DFS_PORTRESET(dfs_addr), BIT_32(port));
755 
756 	while ((mmio_read_32(DFS_PORTSR(dfs_addr)) & BIT_32(port)) != BIT_32(port)) {
757 	}
758 
759 	portolsr = mmio_read_32(DFS_PORTOLSR(dfs_addr));
760 	if ((portolsr & DFS_PORTOLSR_LOL(port)) != 0U) {
761 		ERROR("Failed to lock DFS divider\n");
762 		return -EINVAL;
763 	}
764 
765 	return 0;
766 }
767 
768 static struct s32cc_clk_obj *
769 get_dfs_div_parent(const struct s32cc_clk_obj *module)
770 {
771 	const struct s32cc_dfs_div *dfs_div = s32cc_obj2dfsdiv(module);
772 
773 	if (dfs_div->parent == NULL) {
774 		ERROR("Failed to identify DFS divider's parent\n");
775 	}
776 
777 	return dfs_div->parent;
778 }
779 
780 static int enable_dfs_div(struct s32cc_clk_obj *module,
781 			  const struct s32cc_clk_drv *drv,
782 			  unsigned int depth)
783 {
784 	const struct s32cc_dfs_div *dfs_div = s32cc_obj2dfsdiv(module);
785 	const struct s32cc_pll *pll;
786 	const struct s32cc_dfs *dfs;
787 	uintptr_t dfs_addr = 0UL;
788 	uint32_t mfi, mfn;
789 	int ret = 0;
790 
791 	ret = update_stack_depth(&depth);
792 	if (ret != 0) {
793 		return ret;
794 	}
795 
796 	dfs = get_div_dfs(dfs_div);
797 	if (dfs == NULL) {
798 		return -EINVAL;
799 	}
800 
801 	pll = dfsdiv2pll(dfs_div);
802 	if (pll == NULL) {
803 		ERROR("Failed to identify DFS divider's parent\n");
804 		return -EINVAL;
805 	}
806 
807 	ret = get_base_addr(dfs->instance, drv, &dfs_addr);
808 	if ((ret != 0) || (dfs_addr == 0UL)) {
809 		return -EINVAL;
810 	}
811 
812 	ret = get_dfs_mfi_mfn(pll->vco_freq, dfs_div, &mfi, &mfn);
813 	if (ret != 0) {
814 		return -EINVAL;
815 	}
816 
817 	return init_dfs_port(dfs_addr, dfs_div->index, mfi, mfn);
818 }
819 
820 typedef int (*enable_clk_t)(struct s32cc_clk_obj *module,
821 			    const struct s32cc_clk_drv *drv,
822 			    unsigned int depth);
823 
824 static int no_enable(struct s32cc_clk_obj *module,
825 		     const struct s32cc_clk_drv *drv,
826 		     unsigned int depth)
827 {
828 	return 0;
829 }
830 
831 static int exec_cb_with_refcount(enable_clk_t en_cb, struct s32cc_clk_obj *mod,
832 				 const struct s32cc_clk_drv *drv, bool leaf_node,
833 				 unsigned int depth)
834 {
835 	int ret = 0;
836 
837 	if (mod == NULL) {
838 		return 0;
839 	}
840 
841 	ret = update_stack_depth(&depth);
842 	if (ret != 0) {
843 		return ret;
844 	}
845 
846 	/* Refcount will be updated as part of the recursivity */
847 	if (leaf_node) {
848 		return en_cb(mod, drv, depth);
849 	}
850 
851 	if (mod->refcount == 0U) {
852 		ret = en_cb(mod, drv, depth);
853 	}
854 
855 	if (ret == 0) {
856 		mod->refcount++;
857 	}
858 
859 	return ret;
860 }
861 
862 static struct s32cc_clk_obj *get_module_parent(const struct s32cc_clk_obj *module);
863 
864 static int enable_module(struct s32cc_clk_obj *module,
865 			 const struct s32cc_clk_drv *drv,
866 			 unsigned int depth)
867 {
868 	struct s32cc_clk_obj *parent = get_module_parent(module);
869 	static const enable_clk_t enable_clbs[8] = {
870 		[s32cc_clk_t] = no_enable,
871 		[s32cc_osc_t] = enable_osc,
872 		[s32cc_pll_t] = enable_pll,
873 		[s32cc_pll_out_div_t] = enable_pll_div,
874 		[s32cc_clkmux_t] = enable_mux,
875 		[s32cc_shared_clkmux_t] = enable_mux,
876 		[s32cc_dfs_t] = enable_dfs,
877 		[s32cc_dfs_div_t] = enable_dfs_div,
878 	};
879 	uint32_t index;
880 	int ret = 0;
881 
882 	ret = update_stack_depth(&depth);
883 	if (ret != 0) {
884 		return ret;
885 	}
886 
887 	if (drv == NULL) {
888 		return -EINVAL;
889 	}
890 
891 	index = (uint32_t)module->type;
892 
893 	if (index >= ARRAY_SIZE(enable_clbs)) {
894 		ERROR("Undefined module type: %d\n", module->type);
895 		return -EINVAL;
896 	}
897 
898 	if (enable_clbs[index] == NULL) {
899 		ERROR("Undefined callback for the clock type: %d\n",
900 		      module->type);
901 		return -EINVAL;
902 	}
903 
904 	parent = get_module_parent(module);
905 
906 	ret = exec_cb_with_refcount(enable_module, parent, drv,
907 				    false, depth);
908 	if (ret != 0) {
909 		return ret;
910 	}
911 
912 	ret = exec_cb_with_refcount(enable_clbs[index], module, drv,
913 				    true, depth);
914 	if (ret != 0) {
915 		return ret;
916 	}
917 
918 	return ret;
919 }
920 
921 static int enable_module_with_refcount(struct s32cc_clk_obj *module,
922 				       const struct s32cc_clk_drv *drv,
923 				       unsigned int depth)
924 {
925 	return exec_cb_with_refcount(enable_module, module, drv, false, depth);
926 }
927 
928 static int s32cc_clk_enable(unsigned long id)
929 {
930 	const struct s32cc_clk_drv *drv = get_drv();
931 	unsigned int depth = MAX_STACK_DEPTH;
932 	struct s32cc_clk *clk;
933 
934 	clk = s32cc_get_arch_clk(id);
935 	if (clk == NULL) {
936 		return -EINVAL;
937 	}
938 
939 	return enable_module_with_refcount(&clk->desc, drv, depth);
940 }
941 
942 static void s32cc_clk_disable(unsigned long id)
943 {
944 }
945 
946 static bool s32cc_clk_is_enabled(unsigned long id)
947 {
948 	return false;
949 }
950 
951 static unsigned long s32cc_clk_get_rate(unsigned long id)
952 {
953 	return 0;
954 }
955 
956 static int set_module_rate(const struct s32cc_clk_obj *module,
957 			   unsigned long rate, unsigned long *orate,
958 			   unsigned int *depth);
959 
960 static int set_osc_freq(const struct s32cc_clk_obj *module, unsigned long rate,
961 			unsigned long *orate, unsigned int *depth)
962 {
963 	struct s32cc_osc *osc = s32cc_obj2osc(module);
964 	int ret;
965 
966 	ret = update_stack_depth(depth);
967 	if (ret != 0) {
968 		return ret;
969 	}
970 
971 	if ((osc->freq != 0UL) && (rate != osc->freq)) {
972 		ERROR("Already initialized oscillator. freq = %lu\n",
973 		      osc->freq);
974 		return -EINVAL;
975 	}
976 
977 	osc->freq = rate;
978 	*orate = osc->freq;
979 
980 	return 0;
981 }
982 
983 static int set_clk_freq(const struct s32cc_clk_obj *module, unsigned long rate,
984 			unsigned long *orate, unsigned int *depth)
985 {
986 	const struct s32cc_clk *clk = s32cc_obj2clk(module);
987 	int ret;
988 
989 	ret = update_stack_depth(depth);
990 	if (ret != 0) {
991 		return ret;
992 	}
993 
994 	if ((clk->min_freq != 0UL) && (clk->max_freq != 0UL) &&
995 	    ((rate < clk->min_freq) || (rate > clk->max_freq))) {
996 		ERROR("%lu frequency is out of the allowed range: [%lu:%lu]\n",
997 		      rate, clk->min_freq, clk->max_freq);
998 		return -EINVAL;
999 	}
1000 
1001 	if (clk->module != NULL) {
1002 		return set_module_rate(clk->module, rate, orate, depth);
1003 	}
1004 
1005 	if (clk->pclock != NULL) {
1006 		return set_clk_freq(&clk->pclock->desc, rate, orate, depth);
1007 	}
1008 
1009 	return -EINVAL;
1010 }
1011 
1012 static int set_pll_freq(const struct s32cc_clk_obj *module, unsigned long rate,
1013 			unsigned long *orate, unsigned int *depth)
1014 {
1015 	struct s32cc_pll *pll = s32cc_obj2pll(module);
1016 	int ret;
1017 
1018 	ret = update_stack_depth(depth);
1019 	if (ret != 0) {
1020 		return ret;
1021 	}
1022 
1023 	if ((pll->vco_freq != 0UL) && (pll->vco_freq != rate)) {
1024 		ERROR("PLL frequency was already set\n");
1025 		return -EINVAL;
1026 	}
1027 
1028 	pll->vco_freq = rate;
1029 	*orate = pll->vco_freq;
1030 
1031 	return 0;
1032 }
1033 
1034 static int set_pll_div_freq(const struct s32cc_clk_obj *module, unsigned long rate,
1035 			    unsigned long *orate, unsigned int *depth)
1036 {
1037 	struct s32cc_pll_out_div *pdiv = s32cc_obj2plldiv(module);
1038 	const struct s32cc_pll *pll;
1039 	unsigned long prate, dc;
1040 	int ret;
1041 
1042 	ret = update_stack_depth(depth);
1043 	if (ret != 0) {
1044 		return ret;
1045 	}
1046 
1047 	if (pdiv->parent == NULL) {
1048 		ERROR("Failed to identify PLL divider's parent\n");
1049 		return -EINVAL;
1050 	}
1051 
1052 	pll = s32cc_obj2pll(pdiv->parent);
1053 	if (pll == NULL) {
1054 		ERROR("The parent of the PLL DIV is invalid\n");
1055 		return -EINVAL;
1056 	}
1057 
1058 	prate = pll->vco_freq;
1059 
1060 	/**
1061 	 * The PLL is not initialized yet, so let's take a risk
1062 	 * and accept the proposed rate.
1063 	 */
1064 	if (prate == 0UL) {
1065 		pdiv->freq = rate;
1066 		*orate = rate;
1067 		return 0;
1068 	}
1069 
1070 	/* Decline in case the rate cannot fit PLL's requirements. */
1071 	dc = prate / rate;
1072 	if ((prate / dc) != rate) {
1073 		return -EINVAL;
1074 	}
1075 
1076 	pdiv->freq = rate;
1077 	*orate = pdiv->freq;
1078 
1079 	return 0;
1080 }
1081 
1082 static int set_fixed_div_freq(const struct s32cc_clk_obj *module, unsigned long rate,
1083 			      unsigned long *orate, unsigned int *depth)
1084 {
1085 	const struct s32cc_fixed_div *fdiv = s32cc_obj2fixeddiv(module);
1086 	int ret;
1087 
1088 	ret = update_stack_depth(depth);
1089 	if (ret != 0) {
1090 		return ret;
1091 	}
1092 
1093 	if (fdiv->parent == NULL) {
1094 		ERROR("The divider doesn't have a valid parent\b");
1095 		return -EINVAL;
1096 	}
1097 
1098 	ret = set_module_rate(fdiv->parent, rate * fdiv->rate_div, orate, depth);
1099 
1100 	/* Update the output rate based on the parent's rate */
1101 	*orate /= fdiv->rate_div;
1102 
1103 	return ret;
1104 }
1105 
1106 static int set_mux_freq(const struct s32cc_clk_obj *module, unsigned long rate,
1107 			unsigned long *orate, unsigned int *depth)
1108 {
1109 	const struct s32cc_clkmux *mux = s32cc_obj2clkmux(module);
1110 	const struct s32cc_clk *clk = s32cc_get_arch_clk(mux->source_id);
1111 	int ret;
1112 
1113 	ret = update_stack_depth(depth);
1114 	if (ret != 0) {
1115 		return ret;
1116 	}
1117 
1118 	if (clk == NULL) {
1119 		ERROR("Mux (id:%" PRIu8 ") without a valid source (%lu)\n",
1120 		      mux->index, mux->source_id);
1121 		return -EINVAL;
1122 	}
1123 
1124 	return set_module_rate(&clk->desc, rate, orate, depth);
1125 }
1126 
1127 static int set_dfs_div_freq(const struct s32cc_clk_obj *module, unsigned long rate,
1128 			    unsigned long *orate, unsigned int *depth)
1129 {
1130 	struct s32cc_dfs_div *dfs_div = s32cc_obj2dfsdiv(module);
1131 	const struct s32cc_dfs *dfs;
1132 	int ret;
1133 
1134 	ret = update_stack_depth(depth);
1135 	if (ret != 0) {
1136 		return ret;
1137 	}
1138 
1139 	if (dfs_div->parent == NULL) {
1140 		ERROR("Failed to identify DFS divider's parent\n");
1141 		return -EINVAL;
1142 	}
1143 
1144 	/* Sanity check */
1145 	dfs = s32cc_obj2dfs(dfs_div->parent);
1146 	if (dfs->parent == NULL) {
1147 		ERROR("Failed to identify DFS's parent\n");
1148 		return -EINVAL;
1149 	}
1150 
1151 	if ((dfs_div->freq != 0U) && (dfs_div->freq != rate)) {
1152 		ERROR("DFS DIV frequency was already set to %lu\n",
1153 		      dfs_div->freq);
1154 		return -EINVAL;
1155 	}
1156 
1157 	dfs_div->freq = rate;
1158 	*orate = rate;
1159 
1160 	return ret;
1161 }
1162 
1163 static int set_module_rate(const struct s32cc_clk_obj *module,
1164 			   unsigned long rate, unsigned long *orate,
1165 			   unsigned int *depth)
1166 {
1167 	int ret = 0;
1168 
1169 	ret = update_stack_depth(depth);
1170 	if (ret != 0) {
1171 		return ret;
1172 	}
1173 
1174 	ret = -EINVAL;
1175 
1176 	switch (module->type) {
1177 	case s32cc_clk_t:
1178 		ret = set_clk_freq(module, rate, orate, depth);
1179 		break;
1180 	case s32cc_osc_t:
1181 		ret = set_osc_freq(module, rate, orate, depth);
1182 		break;
1183 	case s32cc_pll_t:
1184 		ret = set_pll_freq(module, rate, orate, depth);
1185 		break;
1186 	case s32cc_pll_out_div_t:
1187 		ret = set_pll_div_freq(module, rate, orate, depth);
1188 		break;
1189 	case s32cc_fixed_div_t:
1190 		ret = set_fixed_div_freq(module, rate, orate, depth);
1191 		break;
1192 	case s32cc_clkmux_t:
1193 		ret = set_mux_freq(module, rate, orate, depth);
1194 		break;
1195 	case s32cc_shared_clkmux_t:
1196 		ret = set_mux_freq(module, rate, orate, depth);
1197 		break;
1198 	case s32cc_dfs_t:
1199 		ERROR("Setting the frequency of a DFS is not allowed!");
1200 		break;
1201 	case s32cc_dfs_div_t:
1202 		ret = set_dfs_div_freq(module, rate, orate, depth);
1203 		break;
1204 	default:
1205 		break;
1206 	}
1207 
1208 	return ret;
1209 }
1210 
1211 static int s32cc_clk_set_rate(unsigned long id, unsigned long rate,
1212 			      unsigned long *orate)
1213 {
1214 	unsigned int depth = MAX_STACK_DEPTH;
1215 	const struct s32cc_clk *clk;
1216 	int ret;
1217 
1218 	clk = s32cc_get_arch_clk(id);
1219 	if (clk == NULL) {
1220 		return -EINVAL;
1221 	}
1222 
1223 	ret = set_module_rate(&clk->desc, rate, orate, &depth);
1224 	if (ret != 0) {
1225 		ERROR("Failed to set frequency (%lu MHz) for clock %lu\n",
1226 		      rate, id);
1227 	}
1228 
1229 	return ret;
1230 }
1231 
1232 static struct s32cc_clk_obj *get_no_parent(const struct s32cc_clk_obj *module)
1233 {
1234 	return NULL;
1235 }
1236 
1237 typedef struct s32cc_clk_obj *(*get_parent_clb_t)(const struct s32cc_clk_obj *clk_obj);
1238 
1239 static struct s32cc_clk_obj *get_module_parent(const struct s32cc_clk_obj *module)
1240 {
1241 	static const get_parent_clb_t parents_clbs[8] = {
1242 		[s32cc_clk_t] = get_clk_parent,
1243 		[s32cc_osc_t] = get_no_parent,
1244 		[s32cc_pll_t] = get_pll_parent,
1245 		[s32cc_pll_out_div_t] = get_pll_div_parent,
1246 		[s32cc_clkmux_t] = get_mux_parent,
1247 		[s32cc_shared_clkmux_t] = get_mux_parent,
1248 		[s32cc_dfs_t] = get_dfs_parent,
1249 		[s32cc_dfs_div_t] = get_dfs_div_parent,
1250 	};
1251 	uint32_t index;
1252 
1253 	if (module == NULL) {
1254 		return NULL;
1255 	}
1256 
1257 	index = (uint32_t)module->type;
1258 
1259 	if (index >= ARRAY_SIZE(parents_clbs)) {
1260 		ERROR("Undefined module type: %d\n", module->type);
1261 		return NULL;
1262 	}
1263 
1264 	if (parents_clbs[index] == NULL) {
1265 		ERROR("Undefined parent getter for type: %d\n", module->type);
1266 		return NULL;
1267 	}
1268 
1269 	return parents_clbs[index](module);
1270 }
1271 
1272 static int s32cc_clk_get_parent(unsigned long id)
1273 {
1274 	struct s32cc_clk *parent_clk;
1275 	const struct s32cc_clk_obj *parent;
1276 	const struct s32cc_clk *clk;
1277 	unsigned long parent_id;
1278 	int ret;
1279 
1280 	clk = s32cc_get_arch_clk(id);
1281 	if (clk == NULL) {
1282 		return -EINVAL;
1283 	}
1284 
1285 	parent = get_module_parent(clk->module);
1286 	if (parent == NULL) {
1287 		return -EINVAL;
1288 	}
1289 
1290 	parent_clk = s32cc_obj2clk(parent);
1291 	if (parent_clk == NULL) {
1292 		return -EINVAL;
1293 	}
1294 
1295 	ret = s32cc_get_clk_id(parent_clk, &parent_id);
1296 	if (ret != 0) {
1297 		return ret;
1298 	}
1299 
1300 	if (parent_id > (unsigned long)INT_MAX) {
1301 		return -E2BIG;
1302 	}
1303 
1304 	return (int)parent_id;
1305 }
1306 
1307 static int s32cc_clk_set_parent(unsigned long id, unsigned long parent_id)
1308 {
1309 	const struct s32cc_clk *parent;
1310 	const struct s32cc_clk *clk;
1311 	bool valid_source = false;
1312 	struct s32cc_clkmux *mux;
1313 	uint8_t i;
1314 
1315 	clk = s32cc_get_arch_clk(id);
1316 	if (clk == NULL) {
1317 		return -EINVAL;
1318 	}
1319 
1320 	parent = s32cc_get_arch_clk(parent_id);
1321 	if (parent == NULL) {
1322 		return -EINVAL;
1323 	}
1324 
1325 	if (!is_s32cc_clk_mux(clk)) {
1326 		ERROR("Clock %lu is not a mux\n", id);
1327 		return -EINVAL;
1328 	}
1329 
1330 	mux = s32cc_clk2mux(clk);
1331 	if (mux == NULL) {
1332 		ERROR("Failed to cast clock %lu to clock mux\n", id);
1333 		return -EINVAL;
1334 	}
1335 
1336 	for (i = 0; i < mux->nclks; i++) {
1337 		if (mux->clkids[i] == parent_id) {
1338 			valid_source = true;
1339 			break;
1340 		}
1341 	}
1342 
1343 	if (!valid_source) {
1344 		ERROR("Clock %lu is not a valid clock for mux %lu\n",
1345 		      parent_id, id);
1346 		return -EINVAL;
1347 	}
1348 
1349 	mux->source_id = parent_id;
1350 
1351 	return 0;
1352 }
1353 
1354 void s32cc_clk_register_drv(void)
1355 {
1356 	static const struct clk_ops s32cc_clk_ops = {
1357 		.enable		= s32cc_clk_enable,
1358 		.disable	= s32cc_clk_disable,
1359 		.is_enabled	= s32cc_clk_is_enabled,
1360 		.get_rate	= s32cc_clk_get_rate,
1361 		.set_rate	= s32cc_clk_set_rate,
1362 		.get_parent	= s32cc_clk_get_parent,
1363 		.set_parent	= s32cc_clk_set_parent,
1364 	};
1365 
1366 	clk_register(&s32cc_clk_ops);
1367 }
1368 
1369