xref: /openbmc/u-boot/arch/arm/mach-tegra/clock.c (revision 2399e401)
1 /*
2  * Copyright (c) 2010-2015, NVIDIA CORPORATION.  All rights reserved.
3  *
4  * SPDX-License-Identifier:	GPL-2.0
5  */
6 
7 /* Tegra SoC common clock control functions */
8 
9 #include <common.h>
10 #include <errno.h>
11 #include <asm/io.h>
12 #include <asm/arch/clock.h>
13 #include <asm/arch/tegra.h>
14 #include <asm/arch-tegra/ap.h>
15 #include <asm/arch-tegra/clk_rst.h>
16 #include <asm/arch-tegra/pmc.h>
17 #include <asm/arch-tegra/timer.h>
18 #include <div64.h>
19 #include <fdtdec.h>
20 
21 /*
22  * This is our record of the current clock rate of each clock. We don't
23  * fill all of these in since we are only really interested in clocks which
24  * we use as parents.
25  */
26 static unsigned pll_rate[CLOCK_ID_COUNT];
27 
28 /*
29  * The oscillator frequency is fixed to one of four set values. Based on this
30  * the other clocks are set up appropriately.
31  */
32 static unsigned osc_freq[CLOCK_OSC_FREQ_COUNT] = {
33 	13000000,
34 	19200000,
35 	12000000,
36 	26000000,
37 	38400000,
38 	48000000,
39 };
40 
41 /* return 1 if a peripheral ID is in range */
42 #define clock_type_id_isvalid(id) ((id) >= 0 && \
43 		(id) < CLOCK_TYPE_COUNT)
44 
45 char pllp_valid = 1;	/* PLLP is set up correctly */
46 
47 /* return 1 if a periphc_internal_id is in range */
48 #define periphc_internal_id_isvalid(id) ((id) >= 0 && \
49 		(id) < PERIPHC_COUNT)
50 
51 /* number of clock outputs of a PLL */
52 static const u8 pll_num_clkouts[] = {
53 	1,	/* PLLC */
54 	1,	/* PLLM */
55 	4,	/* PLLP */
56 	1,	/* PLLA */
57 	0,	/* PLLU */
58 	0,	/* PLLD */
59 };
60 
61 int clock_get_osc_bypass(void)
62 {
63 	struct clk_rst_ctlr *clkrst =
64 			(struct clk_rst_ctlr *)NV_PA_CLK_RST_BASE;
65 	u32 reg;
66 
67 	reg = readl(&clkrst->crc_osc_ctrl);
68 	return (reg & OSC_XOBP_MASK) >> OSC_XOBP_SHIFT;
69 }
70 
71 /* Returns a pointer to the registers of the given pll */
72 static struct clk_pll *get_pll(enum clock_id clkid)
73 {
74 	struct clk_rst_ctlr *clkrst =
75 			(struct clk_rst_ctlr *)NV_PA_CLK_RST_BASE;
76 
77 	assert(clock_id_is_pll(clkid));
78 	if (clkid >= (enum clock_id)TEGRA_CLK_PLLS) {
79 		debug("%s: Invalid PLL %d\n", __func__, clkid);
80 		return NULL;
81 	}
82 	return &clkrst->crc_pll[clkid];
83 }
84 
85 __weak struct clk_pll_simple *clock_get_simple_pll(enum clock_id clkid)
86 {
87 	return NULL;
88 }
89 
90 int clock_ll_read_pll(enum clock_id clkid, u32 *divm, u32 *divn,
91 		u32 *divp, u32 *cpcon, u32 *lfcon)
92 {
93 	struct clk_pll *pll = get_pll(clkid);
94 	struct clk_pll_info *pllinfo = &tegra_pll_info_table[clkid];
95 	u32 data;
96 
97 	assert(clkid != CLOCK_ID_USB);
98 
99 	/* Safety check, adds to code size but is small */
100 	if (!clock_id_is_pll(clkid) || clkid == CLOCK_ID_USB)
101 		return -1;
102 	data = readl(&pll->pll_base);
103 	*divm = (data >> pllinfo->m_shift) & pllinfo->m_mask;
104 	*divn = (data >> pllinfo->n_shift) & pllinfo->n_mask;
105 	*divp = (data >> pllinfo->p_shift) & pllinfo->p_mask;
106 	data = readl(&pll->pll_misc);
107 	/* NOTE: On T210, cpcon/lfcon no longer exist, moved to KCP/KVCO */
108 	*cpcon = (data >> pllinfo->kcp_shift) & pllinfo->kcp_mask;
109 	*lfcon = (data >> pllinfo->kvco_shift) & pllinfo->kvco_mask;
110 
111 	return 0;
112 }
113 
114 unsigned long clock_start_pll(enum clock_id clkid, u32 divm, u32 divn,
115 		u32 divp, u32 cpcon, u32 lfcon)
116 {
117 	struct clk_pll *pll = NULL;
118 	struct clk_pll_info *pllinfo = &tegra_pll_info_table[clkid];
119 	struct clk_pll_simple *simple_pll = NULL;
120 	u32 misc_data, data;
121 
122 	if (clkid < (enum clock_id)TEGRA_CLK_PLLS) {
123 		pll = get_pll(clkid);
124 	} else {
125 		simple_pll = clock_get_simple_pll(clkid);
126 		if (!simple_pll) {
127 			debug("%s: Uknown simple PLL %d\n", __func__, clkid);
128 			return 0;
129 		}
130 	}
131 
132 	/*
133 	 * pllinfo has the m/n/p and kcp/kvco mask and shift
134 	 * values for all of the PLLs used in U-Boot, with any
135 	 * SoC differences accounted for.
136 	 *
137 	 * Preserve EN_LOCKDET, etc.
138 	 */
139 	if (pll)
140 		misc_data = readl(&pll->pll_misc);
141 	else
142 		misc_data = readl(&simple_pll->pll_misc);
143 	misc_data &= ~(pllinfo->kcp_mask << pllinfo->kcp_shift);
144 	misc_data |= cpcon << pllinfo->kcp_shift;
145 	misc_data &= ~(pllinfo->kvco_mask << pllinfo->kvco_shift);
146 	misc_data |= lfcon << pllinfo->kvco_shift;
147 
148 	data = (divm << pllinfo->m_shift) | (divn << pllinfo->n_shift);
149 	data |= divp << pllinfo->p_shift;
150 	data |= (1 << PLL_ENABLE_SHIFT);	/* BYPASS s/b 0 already */
151 
152 	if (pll) {
153 		writel(misc_data, &pll->pll_misc);
154 		writel(data, &pll->pll_base);
155 	} else {
156 		writel(misc_data, &simple_pll->pll_misc);
157 		writel(data, &simple_pll->pll_base);
158 	}
159 
160 	/* calculate the stable time */
161 	return timer_get_us() + CLOCK_PLL_STABLE_DELAY_US;
162 }
163 
164 void clock_ll_set_source_divisor(enum periph_id periph_id, unsigned source,
165 			unsigned divisor)
166 {
167 	u32 *reg = get_periph_source_reg(periph_id);
168 	u32 value;
169 
170 	value = readl(reg);
171 
172 	value &= ~OUT_CLK_SOURCE_31_30_MASK;
173 	value |= source << OUT_CLK_SOURCE_31_30_SHIFT;
174 
175 	value &= ~OUT_CLK_DIVISOR_MASK;
176 	value |= divisor << OUT_CLK_DIVISOR_SHIFT;
177 
178 	writel(value, reg);
179 }
180 
181 int clock_ll_set_source_bits(enum periph_id periph_id, int mux_bits,
182 			     unsigned source)
183 {
184 	u32 *reg = get_periph_source_reg(periph_id);
185 
186 	switch (mux_bits) {
187 	case MASK_BITS_31_30:
188 		clrsetbits_le32(reg, OUT_CLK_SOURCE_31_30_MASK,
189 				source << OUT_CLK_SOURCE_31_30_SHIFT);
190 		break;
191 
192 	case MASK_BITS_31_29:
193 		clrsetbits_le32(reg, OUT_CLK_SOURCE_31_29_MASK,
194 				source << OUT_CLK_SOURCE_31_29_SHIFT);
195 		break;
196 
197 	case MASK_BITS_31_28:
198 		clrsetbits_le32(reg, OUT_CLK_SOURCE_31_28_MASK,
199 				source << OUT_CLK_SOURCE_31_28_SHIFT);
200 		break;
201 
202 	default:
203 		return -1;
204 	}
205 
206 	return 0;
207 }
208 
209 static int clock_ll_get_source_bits(enum periph_id periph_id, int mux_bits)
210 {
211 	u32 *reg = get_periph_source_reg(periph_id);
212 	u32 val = readl(reg);
213 
214 	switch (mux_bits) {
215 	case MASK_BITS_31_30:
216 		val >>= OUT_CLK_SOURCE_31_30_SHIFT;
217 		val &= OUT_CLK_SOURCE_31_30_MASK;
218 		return val;
219 	case MASK_BITS_31_29:
220 		val >>= OUT_CLK_SOURCE_31_29_SHIFT;
221 		val &= OUT_CLK_SOURCE_31_29_MASK;
222 		return val;
223 	case MASK_BITS_31_28:
224 		val >>= OUT_CLK_SOURCE_31_28_SHIFT;
225 		val &= OUT_CLK_SOURCE_31_28_MASK;
226 		return val;
227 	default:
228 		return -1;
229 	}
230 }
231 
232 void clock_ll_set_source(enum periph_id periph_id, unsigned source)
233 {
234 	clock_ll_set_source_bits(periph_id, MASK_BITS_31_30, source);
235 }
236 
237 /**
238  * Given the parent's rate and the required rate for the children, this works
239  * out the peripheral clock divider to use, in 7.1 binary format.
240  *
241  * @param divider_bits	number of divider bits (8 or 16)
242  * @param parent_rate	clock rate of parent clock in Hz
243  * @param rate		required clock rate for this clock
244  * @return divider which should be used
245  */
246 static int clk_get_divider(unsigned divider_bits, unsigned long parent_rate,
247 			   unsigned long rate)
248 {
249 	u64 divider = parent_rate * 2;
250 	unsigned max_divider = 1 << divider_bits;
251 
252 	divider += rate - 1;
253 	do_div(divider, rate);
254 
255 	if ((s64)divider - 2 < 0)
256 		return 0;
257 
258 	if ((s64)divider - 2 >= max_divider)
259 		return -1;
260 
261 	return divider - 2;
262 }
263 
264 int clock_set_pllout(enum clock_id clkid, enum pll_out_id pllout, unsigned rate)
265 {
266 	struct clk_pll *pll = get_pll(clkid);
267 	int data = 0, div = 0, offset = 0;
268 
269 	if (!clock_id_is_pll(clkid))
270 		return -1;
271 
272 	if (pllout + 1 > pll_num_clkouts[clkid])
273 		return -1;
274 
275 	div = clk_get_divider(8, pll_rate[clkid], rate);
276 
277 	if (div < 0)
278 		return -1;
279 
280 	/* out2 and out4 are in the high part of the register */
281 	if (pllout == PLL_OUT2 || pllout == PLL_OUT4)
282 		offset = 16;
283 
284 	data = (div << PLL_OUT_RATIO_SHIFT) |
285 			PLL_OUT_OVRRIDE | PLL_OUT_CLKEN | PLL_OUT_RSTN;
286 	clrsetbits_le32(&pll->pll_out[pllout >> 1],
287 			PLL_OUT_RATIO_MASK << offset, data << offset);
288 
289 	return 0;
290 }
291 
292 /**
293  * Given the parent's rate and the divider in 7.1 format, this works out the
294  * resulting peripheral clock rate.
295  *
296  * @param parent_rate	clock rate of parent clock in Hz
297  * @param divider which should be used in 7.1 format
298  * @return effective clock rate of peripheral
299  */
300 static unsigned long get_rate_from_divider(unsigned long parent_rate,
301 					   int divider)
302 {
303 	u64 rate;
304 
305 	rate = (u64)parent_rate * 2;
306 	do_div(rate, divider + 2);
307 	return rate;
308 }
309 
310 unsigned long clock_get_periph_rate(enum periph_id periph_id,
311 		enum clock_id parent)
312 {
313 	u32 *reg = get_periph_source_reg(periph_id);
314 	unsigned parent_rate = pll_rate[parent];
315 	int div = (readl(reg) & OUT_CLK_DIVISOR_MASK) >> OUT_CLK_DIVISOR_SHIFT;
316 
317 	switch (periph_id) {
318 	case PERIPH_ID_UART1:
319 	case PERIPH_ID_UART2:
320 	case PERIPH_ID_UART3:
321 	case PERIPH_ID_UART4:
322 	case PERIPH_ID_UART5:
323 #ifdef CONFIG_TEGRA20
324 		/* There's no divider for these clocks in this SoC. */
325 		return parent_rate;
326 #else
327 		/*
328 		 * This undoes the +2 in get_rate_from_divider() which I
329 		 * believe is incorrect. Ideally we would fix
330 		 * get_rate_from_divider(), but... Removing the +2 from
331 		 * get_rate_from_divider() would probably require remove the -2
332 		 * from the tail of clk_get_divider() since I believe that's
333 		 * only there to invert get_rate_from_divider()'s +2. Observe
334 		 * how find_best_divider() uses those two functions together.
335 		 * However, doing so breaks other stuff, such as Seaboard's
336 		 * display, likely due to clock_set_pllout()'s call to
337 		 * clk_get_divider(). Attempting to fix that by making
338 		 * clock_set_pllout() subtract 2 from clk_get_divider()'s
339 		 * return value doesn't help. In summary this clock driver is
340 		 * quite broken but I'm afraid I have no idea how to fix it
341 		 * without completely replacing it.
342 		 */
343 		div -= 2;
344 		break;
345 #endif
346 	default:
347 		break;
348 	}
349 
350 	return get_rate_from_divider(parent_rate, div);
351 }
352 
353 /**
354  * Find the best available 7.1 format divisor given a parent clock rate and
355  * required child clock rate. This function assumes that a second-stage
356  * divisor is available which can divide by powers of 2 from 1 to 256.
357  *
358  * @param divider_bits	number of divider bits (8 or 16)
359  * @param parent_rate	clock rate of parent clock in Hz
360  * @param rate		required clock rate for this clock
361  * @param extra_div	value for the second-stage divisor (not set if this
362  *			function returns -1.
363  * @return divider which should be used, or -1 if nothing is valid
364  *
365  */
366 static int find_best_divider(unsigned divider_bits, unsigned long parent_rate,
367 				unsigned long rate, int *extra_div)
368 {
369 	int shift;
370 	int best_divider = -1;
371 	int best_error = rate;
372 
373 	/* try dividers from 1 to 256 and find closest match */
374 	for (shift = 0; shift <= 8 && best_error > 0; shift++) {
375 		unsigned divided_parent = parent_rate >> shift;
376 		int divider = clk_get_divider(divider_bits, divided_parent,
377 						rate);
378 		unsigned effective_rate = get_rate_from_divider(divided_parent,
379 						divider);
380 		int error = rate - effective_rate;
381 
382 		/* Given a valid divider, look for the lowest error */
383 		if (divider != -1 && error < best_error) {
384 			best_error = error;
385 			*extra_div = 1 << shift;
386 			best_divider = divider;
387 		}
388 	}
389 
390 	/* return what we found - *extra_div will already be set */
391 	return best_divider;
392 }
393 
394 /**
395  * Adjust peripheral PLL to use the given divider and source.
396  *
397  * @param periph_id	peripheral to adjust
398  * @param source	Source number (0-3 or 0-7)
399  * @param mux_bits	Number of mux bits (2 or 4)
400  * @param divider	Required divider in 7.1 or 15.1 format
401  * @return 0 if ok, -1 on error (requesting a parent clock which is not valid
402  *		for this peripheral)
403  */
404 static int adjust_periph_pll(enum periph_id periph_id, int source,
405 				int mux_bits, unsigned divider)
406 {
407 	u32 *reg = get_periph_source_reg(periph_id);
408 
409 	clrsetbits_le32(reg, OUT_CLK_DIVISOR_MASK,
410 			divider << OUT_CLK_DIVISOR_SHIFT);
411 	udelay(1);
412 
413 	/* work out the source clock and set it */
414 	if (source < 0)
415 		return -1;
416 
417 	clock_ll_set_source_bits(periph_id, mux_bits, source);
418 
419 	udelay(2);
420 	return 0;
421 }
422 
423 enum clock_id clock_get_periph_parent(enum periph_id periph_id)
424 {
425 	int err, mux_bits, divider_bits, type;
426 	int source;
427 
428 	err = get_periph_clock_info(periph_id, &mux_bits, &divider_bits, &type);
429 	if (err)
430 		return CLOCK_ID_NONE;
431 
432 	source = clock_ll_get_source_bits(periph_id, mux_bits);
433 
434 	return get_periph_clock_id(periph_id, source);
435 }
436 
437 unsigned clock_adjust_periph_pll_div(enum periph_id periph_id,
438 		enum clock_id parent, unsigned rate, int *extra_div)
439 {
440 	unsigned effective_rate;
441 	int mux_bits, divider_bits, source;
442 	int divider;
443 	int xdiv = 0;
444 
445 	/* work out the source clock and set it */
446 	source = get_periph_clock_source(periph_id, parent, &mux_bits,
447 					 &divider_bits);
448 
449 	divider = find_best_divider(divider_bits, pll_rate[parent],
450 				    rate, &xdiv);
451 	if (extra_div)
452 		*extra_div = xdiv;
453 
454 	assert(divider >= 0);
455 	if (adjust_periph_pll(periph_id, source, mux_bits, divider))
456 		return -1U;
457 	debug("periph %d, rate=%d, reg=%p = %x\n", periph_id, rate,
458 		get_periph_source_reg(periph_id),
459 		readl(get_periph_source_reg(periph_id)));
460 
461 	/* Check what we ended up with. This shouldn't matter though */
462 	effective_rate = clock_get_periph_rate(periph_id, parent);
463 	if (extra_div)
464 		effective_rate /= *extra_div;
465 	if (rate != effective_rate)
466 		debug("Requested clock rate %u not honored (got %u)\n",
467 			rate, effective_rate);
468 	return effective_rate;
469 }
470 
471 unsigned clock_start_periph_pll(enum periph_id periph_id,
472 		enum clock_id parent, unsigned rate)
473 {
474 	unsigned effective_rate;
475 
476 	reset_set_enable(periph_id, 1);
477 	clock_enable(periph_id);
478 
479 	effective_rate = clock_adjust_periph_pll_div(periph_id, parent, rate,
480 						 NULL);
481 
482 	reset_set_enable(periph_id, 0);
483 	return effective_rate;
484 }
485 
486 void clock_enable(enum periph_id clkid)
487 {
488 	clock_set_enable(clkid, 1);
489 }
490 
491 void clock_disable(enum periph_id clkid)
492 {
493 	clock_set_enable(clkid, 0);
494 }
495 
496 void reset_periph(enum periph_id periph_id, int us_delay)
497 {
498 	/* Put peripheral into reset */
499 	reset_set_enable(periph_id, 1);
500 	udelay(us_delay);
501 
502 	/* Remove reset */
503 	reset_set_enable(periph_id, 0);
504 
505 	udelay(us_delay);
506 }
507 
508 void reset_cmplx_set_enable(int cpu, int which, int reset)
509 {
510 	struct clk_rst_ctlr *clkrst =
511 			(struct clk_rst_ctlr *)NV_PA_CLK_RST_BASE;
512 	u32 mask;
513 
514 	/* Form the mask, which depends on the cpu chosen (2 or 4) */
515 	assert(cpu >= 0 && cpu < MAX_NUM_CPU);
516 	mask = which << cpu;
517 
518 	/* either enable or disable those reset for that CPU */
519 	if (reset)
520 		writel(mask, &clkrst->crc_cpu_cmplx_set);
521 	else
522 		writel(mask, &clkrst->crc_cpu_cmplx_clr);
523 }
524 
525 unsigned int __weak clk_m_get_rate(unsigned int parent_rate)
526 {
527 	return parent_rate;
528 }
529 
530 unsigned clock_get_rate(enum clock_id clkid)
531 {
532 	struct clk_pll *pll;
533 	u32 base, divm;
534 	u64 parent_rate, rate;
535 	struct clk_pll_info *pllinfo = &tegra_pll_info_table[clkid];
536 
537 	parent_rate = osc_freq[clock_get_osc_freq()];
538 	if (clkid == CLOCK_ID_OSC)
539 		return parent_rate;
540 
541 	if (clkid == CLOCK_ID_CLK_M)
542 		return clk_m_get_rate(parent_rate);
543 
544 	pll = get_pll(clkid);
545 	if (!pll)
546 		return 0;
547 	base = readl(&pll->pll_base);
548 
549 	rate = parent_rate * ((base >> pllinfo->n_shift) & pllinfo->n_mask);
550 	divm = (base >> pllinfo->m_shift) & pllinfo->m_mask;
551 	/*
552 	 * PLLU uses p_mask/p_shift for VCO on all but T210,
553 	 * T210 uses normal DIVP. Handled in pllinfo table.
554 	 */
555 #ifdef CONFIG_TEGRA210
556 	/*
557 	 * PLLP's primary output (pllP_out0) on T210 is the VCO, and divp is
558 	 * not applied. pllP_out2 does have divp applied. All other pllP_outN
559 	 * are divided down from pllP_out0. We only support pllP_out0 in
560 	 * U-Boot at the time of writing this comment.
561 	 */
562 	if (clkid != CLOCK_ID_PERIPH)
563 #endif
564 		divm <<= (base >> pllinfo->p_shift) & pllinfo->p_mask;
565 	do_div(rate, divm);
566 	return rate;
567 }
568 
569 /**
570  * Set the output frequency you want for each PLL clock.
571  * PLL output frequencies are programmed by setting their N, M and P values.
572  * The governing equations are:
573  *     VCO = (Fi / m) * n, Fo = VCO / (2^p)
574  *     where Fo is the output frequency from the PLL.
575  * Example: Set the output frequency to 216Mhz(Fo) with 12Mhz OSC(Fi)
576  *     216Mhz = ((12Mhz / m) * n) / (2^p) so n=432,m=12,p=1
577  * Please see Tegra TRM section 5.3 to get the detail for PLL Programming
578  *
579  * @param n PLL feedback divider(DIVN)
580  * @param m PLL input divider(DIVN)
581  * @param p post divider(DIVP)
582  * @param cpcon base PLL charge pump(CPCON)
583  * @return 0 if ok, -1 on error (the requested PLL is incorrect and cannot
584  *		be overridden), 1 if PLL is already correct
585  */
586 int clock_set_rate(enum clock_id clkid, u32 n, u32 m, u32 p, u32 cpcon)
587 {
588 	u32 base_reg, misc_reg;
589 	struct clk_pll *pll;
590 	struct clk_pll_info *pllinfo = &tegra_pll_info_table[clkid];
591 
592 	pll = get_pll(clkid);
593 
594 	base_reg = readl(&pll->pll_base);
595 
596 	/* Set BYPASS, m, n and p to PLL_BASE */
597 	base_reg &= ~(pllinfo->m_mask << pllinfo->m_shift);
598 	base_reg |= m << pllinfo->m_shift;
599 
600 	base_reg &= ~(pllinfo->n_mask << pllinfo->n_shift);
601 	base_reg |= n << pllinfo->n_shift;
602 
603 	base_reg &= ~(pllinfo->p_mask << pllinfo->p_shift);
604 	base_reg |= p << pllinfo->p_shift;
605 
606 	if (clkid == CLOCK_ID_PERIPH) {
607 		/*
608 		 * If the PLL is already set up, check that it is correct
609 		 * and record this info for clock_verify() to check.
610 		 */
611 		if (base_reg & PLL_BASE_OVRRIDE_MASK) {
612 			base_reg |= PLL_ENABLE_MASK;
613 			if (base_reg != readl(&pll->pll_base))
614 				pllp_valid = 0;
615 			return pllp_valid ? 1 : -1;
616 		}
617 		base_reg |= PLL_BASE_OVRRIDE_MASK;
618 	}
619 
620 	base_reg |= PLL_BYPASS_MASK;
621 	writel(base_reg, &pll->pll_base);
622 
623 	/* Set cpcon (KCP) to PLL_MISC */
624 	misc_reg = readl(&pll->pll_misc);
625 	misc_reg &= ~(pllinfo->kcp_mask << pllinfo->kcp_shift);
626 	misc_reg |= cpcon << pllinfo->kcp_shift;
627 	writel(misc_reg, &pll->pll_misc);
628 
629 	/* Enable PLL */
630 	base_reg |= PLL_ENABLE_MASK;
631 	writel(base_reg, &pll->pll_base);
632 
633 	/* Disable BYPASS */
634 	base_reg &= ~PLL_BYPASS_MASK;
635 	writel(base_reg, &pll->pll_base);
636 
637 	return 0;
638 }
639 
640 void clock_ll_start_uart(enum periph_id periph_id)
641 {
642 	/* Assert UART reset and enable clock */
643 	reset_set_enable(periph_id, 1);
644 	clock_enable(periph_id);
645 	clock_ll_set_source(periph_id, 0); /* UARTx_CLK_SRC = 00, PLLP_OUT0 */
646 
647 	/* wait for 2us */
648 	udelay(2);
649 
650 	/* De-assert reset to UART */
651 	reset_set_enable(periph_id, 0);
652 }
653 
654 #if CONFIG_IS_ENABLED(OF_CONTROL)
655 int clock_decode_periph_id(const void *blob, int node)
656 {
657 	enum periph_id id;
658 	u32 cell[2];
659 	int err;
660 
661 	err = fdtdec_get_int_array(blob, node, "clocks", cell,
662 				   ARRAY_SIZE(cell));
663 	if (err)
664 		return -1;
665 	id = clk_id_to_periph_id(cell[1]);
666 	assert(clock_periph_id_isvalid(id));
667 	return id;
668 }
669 #endif /* CONFIG_IS_ENABLED(OF_CONTROL) */
670 
671 int clock_verify(void)
672 {
673 	struct clk_pll *pll = get_pll(CLOCK_ID_PERIPH);
674 	u32 reg = readl(&pll->pll_base);
675 
676 	if (!pllp_valid) {
677 		printf("Warning: PLLP %x is not correct\n", reg);
678 		return -1;
679 	}
680 	debug("PLLP %x is correct\n", reg);
681 	return 0;
682 }
683 
684 void clock_init(void)
685 {
686 	int i;
687 
688 	pll_rate[CLOCK_ID_CGENERAL] = clock_get_rate(CLOCK_ID_CGENERAL);
689 	pll_rate[CLOCK_ID_MEMORY] = clock_get_rate(CLOCK_ID_MEMORY);
690 	pll_rate[CLOCK_ID_PERIPH] = clock_get_rate(CLOCK_ID_PERIPH);
691 	pll_rate[CLOCK_ID_USB] = clock_get_rate(CLOCK_ID_USB);
692 	pll_rate[CLOCK_ID_DISPLAY] = clock_get_rate(CLOCK_ID_DISPLAY);
693 	pll_rate[CLOCK_ID_XCPU] = clock_get_rate(CLOCK_ID_XCPU);
694 	pll_rate[CLOCK_ID_SFROM32KHZ] = 32768;
695 	pll_rate[CLOCK_ID_OSC] = clock_get_rate(CLOCK_ID_OSC);
696 	pll_rate[CLOCK_ID_CLK_M] = clock_get_rate(CLOCK_ID_CLK_M);
697 
698 	debug("Osc = %d\n", pll_rate[CLOCK_ID_OSC]);
699 	debug("CLKM = %d\n", pll_rate[CLOCK_ID_CLK_M]);
700 	debug("PLLC = %d\n", pll_rate[CLOCK_ID_CGENERAL]);
701 	debug("PLLM = %d\n", pll_rate[CLOCK_ID_MEMORY]);
702 	debug("PLLP = %d\n", pll_rate[CLOCK_ID_PERIPH]);
703 	debug("PLLU = %d\n", pll_rate[CLOCK_ID_USB]);
704 	debug("PLLD = %d\n", pll_rate[CLOCK_ID_DISPLAY]);
705 	debug("PLLX = %d\n", pll_rate[CLOCK_ID_XCPU]);
706 
707 	for (i = 0; periph_clk_init_table[i].periph_id != -1; i++) {
708 		enum periph_id periph_id;
709 		enum clock_id parent;
710 		int source, mux_bits, divider_bits;
711 
712 		periph_id = periph_clk_init_table[i].periph_id;
713 		parent = periph_clk_init_table[i].parent_clock_id;
714 
715 		source = get_periph_clock_source(periph_id, parent, &mux_bits,
716 						 &divider_bits);
717 		clock_ll_set_source_bits(periph_id, mux_bits, source);
718 	}
719 }
720 
721 static void set_avp_clock_source(u32 src)
722 {
723 	struct clk_rst_ctlr *clkrst =
724 			(struct clk_rst_ctlr *)NV_PA_CLK_RST_BASE;
725 	u32 val;
726 
727 	val = (src << SCLK_SWAKEUP_FIQ_SOURCE_SHIFT) |
728 		(src << SCLK_SWAKEUP_IRQ_SOURCE_SHIFT) |
729 		(src << SCLK_SWAKEUP_RUN_SOURCE_SHIFT) |
730 		(src << SCLK_SWAKEUP_IDLE_SOURCE_SHIFT) |
731 		(SCLK_SYS_STATE_RUN << SCLK_SYS_STATE_SHIFT);
732 	writel(val, &clkrst->crc_sclk_brst_pol);
733 	udelay(3);
734 }
735 
736 /*
737  * This function is useful on Tegra30, and any later SoCs that have compatible
738  * PLLP configuration registers.
739  * NOTE: Not used on Tegra210 - see tegra210_setup_pllp in T210 clock.c
740  */
741 void tegra30_set_up_pllp(void)
742 {
743 	struct clk_rst_ctlr *clkrst = (struct clk_rst_ctlr *)NV_PA_CLK_RST_BASE;
744 	u32 reg;
745 
746 	/*
747 	 * Based on the Tegra TRM, the system clock (which is the AVP clock) can
748 	 * run up to 275MHz. On power on, the default sytem clock source is set
749 	 * to PLLP_OUT0. This function sets PLLP's (hence PLLP_OUT0's) rate to
750 	 * 408MHz which is beyond system clock's upper limit.
751 	 *
752 	 * The fix is to set the system clock to CLK_M before initializing PLLP,
753 	 * and then switch back to PLLP_OUT4, which has an appropriate divider
754 	 * configured, after PLLP has been configured
755 	 */
756 	set_avp_clock_source(SCLK_SOURCE_CLKM);
757 
758 	/*
759 	 * PLLP output frequency set to 408Mhz
760 	 * PLLC output frequency set to 228Mhz
761 	 */
762 	switch (clock_get_osc_freq()) {
763 	case CLOCK_OSC_FREQ_12_0: /* OSC is 12Mhz */
764 		clock_set_rate(CLOCK_ID_PERIPH, 408, 12, 0, 8);
765 		clock_set_rate(CLOCK_ID_CGENERAL, 456, 12, 1, 8);
766 		break;
767 
768 	case CLOCK_OSC_FREQ_26_0: /* OSC is 26Mhz */
769 		clock_set_rate(CLOCK_ID_PERIPH, 408, 26, 0, 8);
770 		clock_set_rate(CLOCK_ID_CGENERAL, 600, 26, 0, 8);
771 		break;
772 
773 	case CLOCK_OSC_FREQ_13_0: /* OSC is 13Mhz */
774 		clock_set_rate(CLOCK_ID_PERIPH, 408, 13, 0, 8);
775 		clock_set_rate(CLOCK_ID_CGENERAL, 600, 13, 0, 8);
776 		break;
777 	case CLOCK_OSC_FREQ_19_2:
778 	default:
779 		/*
780 		 * These are not supported. It is too early to print a
781 		 * message and the UART likely won't work anyway due to the
782 		 * oscillator being wrong.
783 		 */
784 		break;
785 	}
786 
787 	/* Set PLLP_OUT1, 2, 3 & 4 freqs to 9.6, 48, 102 & 204MHz */
788 
789 	/* OUT1, 2 */
790 	/* Assert RSTN before enable */
791 	reg = PLLP_OUT2_RSTN_EN | PLLP_OUT1_RSTN_EN;
792 	writel(reg, &clkrst->crc_pll[CLOCK_ID_PERIPH].pll_out[0]);
793 	/* Set divisor and reenable */
794 	reg = (IN_408_OUT_48_DIVISOR << PLLP_OUT2_RATIO)
795 		| PLLP_OUT2_OVR | PLLP_OUT2_CLKEN | PLLP_OUT2_RSTN_DIS
796 		| (IN_408_OUT_9_6_DIVISOR << PLLP_OUT1_RATIO)
797 		| PLLP_OUT1_OVR | PLLP_OUT1_CLKEN | PLLP_OUT1_RSTN_DIS;
798 	writel(reg, &clkrst->crc_pll[CLOCK_ID_PERIPH].pll_out[0]);
799 
800 	/* OUT3, 4 */
801 	/* Assert RSTN before enable */
802 	reg = PLLP_OUT4_RSTN_EN | PLLP_OUT3_RSTN_EN;
803 	writel(reg, &clkrst->crc_pll[CLOCK_ID_PERIPH].pll_out[1]);
804 	/* Set divisor and reenable */
805 	reg = (IN_408_OUT_204_DIVISOR << PLLP_OUT4_RATIO)
806 		| PLLP_OUT4_OVR | PLLP_OUT4_CLKEN | PLLP_OUT4_RSTN_DIS
807 		| (IN_408_OUT_102_DIVISOR << PLLP_OUT3_RATIO)
808 		| PLLP_OUT3_OVR | PLLP_OUT3_CLKEN | PLLP_OUT3_RSTN_DIS;
809 	writel(reg, &clkrst->crc_pll[CLOCK_ID_PERIPH].pll_out[1]);
810 
811 	set_avp_clock_source(SCLK_SOURCE_PLLP_OUT4);
812 }
813 
814 int clock_external_output(int clk_id)
815 {
816 	struct pmc_ctlr *pmc = (struct pmc_ctlr *)NV_PA_PMC_BASE;
817 
818 	if (clk_id >= 1 && clk_id <= 3) {
819 		setbits_le32(&pmc->pmc_clk_out_cntrl,
820 			     1 << (2 + (clk_id - 1) * 8));
821 	} else {
822 		printf("%s: Unknown output clock id %d\n", __func__, clk_id);
823 		return -EINVAL;
824 	}
825 
826 	return 0;
827 }
828