xref: /openbmc/linux/arch/arm/mach-ep93xx/clock.c (revision 2cf1c348)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * arch/arm/mach-ep93xx/clock.c
4  * Clock control for Cirrus EP93xx chips.
5  *
6  * Copyright (C) 2006 Lennert Buytenhek <buytenh@wantstofly.org>
7  */
8 
9 #define pr_fmt(fmt) "ep93xx " KBUILD_MODNAME ": " fmt
10 
11 #include <linux/kernel.h>
12 #include <linux/clk.h>
13 #include <linux/err.h>
14 #include <linux/module.h>
15 #include <linux/string.h>
16 #include <linux/io.h>
17 #include <linux/spinlock.h>
18 #include <linux/clkdev.h>
19 #include <linux/clk-provider.h>
20 #include <linux/soc/cirrus/ep93xx.h>
21 
22 #include "hardware.h"
23 
24 #include <asm/div64.h>
25 
26 #include "soc.h"
27 
28 static DEFINE_SPINLOCK(clk_lock);
29 
30 static char fclk_divisors[] = { 1, 2, 4, 8, 16, 1, 1, 1 };
31 static char hclk_divisors[] = { 1, 2, 4, 5, 6, 8, 16, 32 };
32 static char pclk_divisors[] = { 1, 2, 4, 8 };
33 
34 static char adc_divisors[] = { 16, 4 };
35 static char sclk_divisors[] = { 2, 4 };
36 static char lrclk_divisors[] = { 32, 64, 128 };
37 
38 static const char * const mux_parents[] = {
39 	"xtali",
40 	"pll1",
41 	"pll2"
42 };
43 
44 /*
45  * PLL rate = 14.7456 MHz * (X1FBD + 1) * (X2FBD + 1) / (X2IPD + 1) / 2^PS
46  */
47 static unsigned long calc_pll_rate(unsigned long long rate, u32 config_word)
48 {
49 	int i;
50 
51 	rate *= ((config_word >> 11) & 0x1f) + 1;		/* X1FBD */
52 	rate *= ((config_word >> 5) & 0x3f) + 1;		/* X2FBD */
53 	do_div(rate, (config_word & 0x1f) + 1);			/* X2IPD */
54 	for (i = 0; i < ((config_word >> 16) & 3); i++)		/* PS */
55 		rate >>= 1;
56 
57 	return (unsigned long)rate;
58 }
59 
60 struct clk_psc {
61 	struct clk_hw hw;
62 	void __iomem *reg;
63 	u8 bit_idx;
64 	u32 mask;
65 	u8 shift;
66 	u8 width;
67 	char *div;
68 	u8 num_div;
69 	spinlock_t *lock;
70 };
71 
72 #define to_clk_psc(_hw) container_of(_hw, struct clk_psc, hw)
73 
74 static int ep93xx_clk_is_enabled(struct clk_hw *hw)
75 {
76 	struct clk_psc *psc = to_clk_psc(hw);
77 	u32 val = readl(psc->reg);
78 
79 	return (val & BIT(psc->bit_idx)) ? 1 : 0;
80 }
81 
82 static int ep93xx_clk_enable(struct clk_hw *hw)
83 {
84 	struct clk_psc *psc = to_clk_psc(hw);
85 	unsigned long flags = 0;
86 	u32 val;
87 
88 	if (psc->lock)
89 		spin_lock_irqsave(psc->lock, flags);
90 
91 	val = __raw_readl(psc->reg);
92 	val |= BIT(psc->bit_idx);
93 
94 	ep93xx_syscon_swlocked_write(val, psc->reg);
95 
96 	if (psc->lock)
97 		spin_unlock_irqrestore(psc->lock, flags);
98 
99 	return 0;
100 }
101 
102 static void ep93xx_clk_disable(struct clk_hw *hw)
103 {
104 	struct clk_psc *psc = to_clk_psc(hw);
105 	unsigned long flags = 0;
106 	u32 val;
107 
108 	if (psc->lock)
109 		spin_lock_irqsave(psc->lock, flags);
110 
111 	val = __raw_readl(psc->reg);
112 	val &= ~BIT(psc->bit_idx);
113 
114 	ep93xx_syscon_swlocked_write(val, psc->reg);
115 
116 	if (psc->lock)
117 		spin_unlock_irqrestore(psc->lock, flags);
118 }
119 
120 static const struct clk_ops clk_ep93xx_gate_ops = {
121 	.enable = ep93xx_clk_enable,
122 	.disable = ep93xx_clk_disable,
123 	.is_enabled = ep93xx_clk_is_enabled,
124 };
125 
126 static struct clk_hw *ep93xx_clk_register_gate(const char *name,
127 				    const char *parent_name,
128 				    void __iomem *reg,
129 				    u8 bit_idx)
130 {
131 	struct clk_init_data init;
132 	struct clk_psc *psc;
133 	struct clk *clk;
134 
135 	psc = kzalloc(sizeof(*psc), GFP_KERNEL);
136 	if (!psc)
137 		return ERR_PTR(-ENOMEM);
138 
139 	init.name = name;
140 	init.ops = &clk_ep93xx_gate_ops;
141 	init.flags = CLK_SET_RATE_PARENT;
142 	init.parent_names = (parent_name ? &parent_name : NULL);
143 	init.num_parents = (parent_name ? 1 : 0);
144 
145 	psc->reg = reg;
146 	psc->bit_idx = bit_idx;
147 	psc->hw.init = &init;
148 	psc->lock = &clk_lock;
149 
150 	clk = clk_register(NULL, &psc->hw);
151 	if (IS_ERR(clk))
152 		kfree(psc);
153 
154 	return &psc->hw;
155 }
156 
157 static u8 ep93xx_mux_get_parent(struct clk_hw *hw)
158 {
159 	struct clk_psc *psc = to_clk_psc(hw);
160 	u32 val = __raw_readl(psc->reg);
161 
162 	if (!(val & EP93XX_SYSCON_CLKDIV_ESEL))
163 		return 0;
164 
165 	if (!(val & EP93XX_SYSCON_CLKDIV_PSEL))
166 		return 1;
167 
168 	return 2;
169 }
170 
171 static int ep93xx_mux_set_parent_lock(struct clk_hw *hw, u8 index)
172 {
173 	struct clk_psc *psc = to_clk_psc(hw);
174 	unsigned long flags = 0;
175 	u32 val;
176 
177 	if (index >= ARRAY_SIZE(mux_parents))
178 		return -EINVAL;
179 
180 	if (psc->lock)
181 		spin_lock_irqsave(psc->lock, flags);
182 
183 	val = __raw_readl(psc->reg);
184 	val &= ~(EP93XX_SYSCON_CLKDIV_ESEL | EP93XX_SYSCON_CLKDIV_PSEL);
185 
186 
187 	if (index != 0) {
188 		val |= EP93XX_SYSCON_CLKDIV_ESEL;
189 		val |= (index - 1) ? EP93XX_SYSCON_CLKDIV_PSEL : 0;
190 	}
191 
192 	ep93xx_syscon_swlocked_write(val, psc->reg);
193 
194 	if (psc->lock)
195 		spin_unlock_irqrestore(psc->lock, flags);
196 
197 	return 0;
198 }
199 
200 static bool is_best(unsigned long rate, unsigned long now,
201 		     unsigned long best)
202 {
203 	return abs(rate - now) < abs(rate - best);
204 }
205 
206 static int ep93xx_mux_determine_rate(struct clk_hw *hw,
207 				struct clk_rate_request *req)
208 {
209 	unsigned long rate = req->rate;
210 	struct clk *best_parent = 0;
211 	unsigned long __parent_rate;
212 	unsigned long best_rate = 0, actual_rate, mclk_rate;
213 	unsigned long best_parent_rate;
214 	int __div = 0, __pdiv = 0;
215 	int i;
216 
217 	/*
218 	 * Try the two pll's and the external clock
219 	 * Because the valid predividers are 2, 2.5 and 3, we multiply
220 	 * all the clocks by 2 to avoid floating point math.
221 	 *
222 	 * This is based on the algorithm in the ep93xx raster guide:
223 	 * http://be-a-maverick.com/en/pubs/appNote/AN269REV1.pdf
224 	 *
225 	 */
226 	for (i = 0; i < ARRAY_SIZE(mux_parents); i++) {
227 		struct clk *parent = clk_get_sys(mux_parents[i], NULL);
228 
229 		__parent_rate = clk_get_rate(parent);
230 		mclk_rate = __parent_rate * 2;
231 
232 		/* Try each predivider value */
233 		for (__pdiv = 4; __pdiv <= 6; __pdiv++) {
234 			__div = mclk_rate / (rate * __pdiv);
235 			if (__div < 2 || __div > 127)
236 				continue;
237 
238 			actual_rate = mclk_rate / (__pdiv * __div);
239 			if (is_best(rate, actual_rate, best_rate)) {
240 				best_rate = actual_rate;
241 				best_parent_rate = __parent_rate;
242 				best_parent = parent;
243 			}
244 		}
245 	}
246 
247 	if (!best_parent)
248 		return -EINVAL;
249 
250 	req->best_parent_rate = best_parent_rate;
251 	req->best_parent_hw = __clk_get_hw(best_parent);
252 	req->rate = best_rate;
253 
254 	return 0;
255 }
256 
257 static unsigned long ep93xx_ddiv_recalc_rate(struct clk_hw *hw,
258 						unsigned long parent_rate)
259 {
260 	struct clk_psc *psc = to_clk_psc(hw);
261 	unsigned long rate = 0;
262 	u32 val = __raw_readl(psc->reg);
263 	int __pdiv = ((val >> EP93XX_SYSCON_CLKDIV_PDIV_SHIFT) & 0x03);
264 	int __div = val & 0x7f;
265 
266 	if (__div > 0)
267 		rate = (parent_rate * 2) / ((__pdiv + 3) * __div);
268 
269 	return rate;
270 }
271 
272 static int ep93xx_ddiv_set_rate(struct clk_hw *hw, unsigned long rate,
273 				unsigned long parent_rate)
274 {
275 	struct clk_psc *psc = to_clk_psc(hw);
276 	int pdiv = 0, div = 0;
277 	unsigned long best_rate = 0, actual_rate, mclk_rate;
278 	int __div = 0, __pdiv = 0;
279 	u32 val;
280 
281 	mclk_rate = parent_rate * 2;
282 
283 	for (__pdiv = 4; __pdiv <= 6; __pdiv++) {
284 		__div = mclk_rate / (rate * __pdiv);
285 		if (__div < 2 || __div > 127)
286 			continue;
287 
288 		actual_rate = mclk_rate / (__pdiv * __div);
289 		if (is_best(rate, actual_rate, best_rate)) {
290 			pdiv = __pdiv - 3;
291 			div = __div;
292 			best_rate = actual_rate;
293 		}
294 	}
295 
296 	if (!best_rate)
297 		return -EINVAL;
298 
299 	val = __raw_readl(psc->reg);
300 
301 	/* Clear old dividers */
302 	val &= ~0x37f;
303 
304 	/* Set the new pdiv and div bits for the new clock rate */
305 	val |= (pdiv << EP93XX_SYSCON_CLKDIV_PDIV_SHIFT) | div;
306 	ep93xx_syscon_swlocked_write(val, psc->reg);
307 
308 	return 0;
309 }
310 
311 static const struct clk_ops clk_ddiv_ops = {
312 	.enable = ep93xx_clk_enable,
313 	.disable = ep93xx_clk_disable,
314 	.is_enabled = ep93xx_clk_is_enabled,
315 	.get_parent = ep93xx_mux_get_parent,
316 	.set_parent = ep93xx_mux_set_parent_lock,
317 	.determine_rate = ep93xx_mux_determine_rate,
318 	.recalc_rate = ep93xx_ddiv_recalc_rate,
319 	.set_rate = ep93xx_ddiv_set_rate,
320 };
321 
322 static struct clk_hw *clk_hw_register_ddiv(const char *name,
323 					  void __iomem *reg,
324 					  u8 bit_idx)
325 {
326 	struct clk_init_data init;
327 	struct clk_psc *psc;
328 	struct clk *clk;
329 
330 	psc = kzalloc(sizeof(*psc), GFP_KERNEL);
331 	if (!psc)
332 		return ERR_PTR(-ENOMEM);
333 
334 	init.name = name;
335 	init.ops = &clk_ddiv_ops;
336 	init.flags = 0;
337 	init.parent_names = mux_parents;
338 	init.num_parents = ARRAY_SIZE(mux_parents);
339 
340 	psc->reg = reg;
341 	psc->bit_idx = bit_idx;
342 	psc->lock = &clk_lock;
343 	psc->hw.init = &init;
344 
345 	clk = clk_register(NULL, &psc->hw);
346 	if (IS_ERR(clk))
347 		kfree(psc);
348 
349 	return &psc->hw;
350 }
351 
352 static unsigned long ep93xx_div_recalc_rate(struct clk_hw *hw,
353 					    unsigned long parent_rate)
354 {
355 	struct clk_psc *psc = to_clk_psc(hw);
356 	u32 val = __raw_readl(psc->reg);
357 	u8 index = (val & psc->mask) >> psc->shift;
358 
359 	if (index > psc->num_div)
360 		return 0;
361 
362 	return DIV_ROUND_UP_ULL(parent_rate, psc->div[index]);
363 }
364 
365 static long ep93xx_div_round_rate(struct clk_hw *hw, unsigned long rate,
366 				   unsigned long *parent_rate)
367 {
368 	struct clk_psc *psc = to_clk_psc(hw);
369 	unsigned long best = 0, now, maxdiv;
370 	int i;
371 
372 	maxdiv = psc->div[psc->num_div - 1];
373 
374 	for (i = 0; i < psc->num_div; i++) {
375 		if ((rate * psc->div[i]) == *parent_rate)
376 			return DIV_ROUND_UP_ULL((u64)*parent_rate, psc->div[i]);
377 
378 		now = DIV_ROUND_UP_ULL((u64)*parent_rate, psc->div[i]);
379 
380 		if (is_best(rate, now, best))
381 			best = now;
382 	}
383 
384 	if (!best)
385 		best = DIV_ROUND_UP_ULL(*parent_rate, maxdiv);
386 
387 	return best;
388 }
389 
390 static int ep93xx_div_set_rate(struct clk_hw *hw, unsigned long rate,
391 			       unsigned long parent_rate)
392 {
393 	struct clk_psc *psc = to_clk_psc(hw);
394 	u32 val = __raw_readl(psc->reg) & ~psc->mask;
395 	int i;
396 
397 	for (i = 0; i < psc->num_div; i++)
398 		if (rate == parent_rate / psc->div[i]) {
399 			val |= i << psc->shift;
400 			break;
401 		}
402 
403 	if (i == psc->num_div)
404 		return -EINVAL;
405 
406 	ep93xx_syscon_swlocked_write(val, psc->reg);
407 
408 	return 0;
409 }
410 
411 static const struct clk_ops ep93xx_div_ops = {
412 	.enable = ep93xx_clk_enable,
413 	.disable = ep93xx_clk_disable,
414 	.is_enabled = ep93xx_clk_is_enabled,
415 	.recalc_rate = ep93xx_div_recalc_rate,
416 	.round_rate = ep93xx_div_round_rate,
417 	.set_rate = ep93xx_div_set_rate,
418 };
419 
420 static struct clk_hw *clk_hw_register_div(const char *name,
421 					  const char *parent_name,
422 					  void __iomem *reg,
423 					  u8 enable_bit,
424 					  u8 shift,
425 					  u8 width,
426 					  char *clk_divisors,
427 					  u8 num_div)
428 {
429 	struct clk_init_data init;
430 	struct clk_psc *psc;
431 	struct clk *clk;
432 
433 	psc = kzalloc(sizeof(*psc), GFP_KERNEL);
434 	if (!psc)
435 		return ERR_PTR(-ENOMEM);
436 
437 	init.name = name;
438 	init.ops = &ep93xx_div_ops;
439 	init.flags = 0;
440 	init.parent_names = (parent_name ? &parent_name : NULL);
441 	init.num_parents = 1;
442 
443 	psc->reg = reg;
444 	psc->bit_idx = enable_bit;
445 	psc->mask = GENMASK(shift + width - 1, shift);
446 	psc->shift = shift;
447 	psc->div = clk_divisors;
448 	psc->num_div = num_div;
449 	psc->lock = &clk_lock;
450 	psc->hw.init = &init;
451 
452 	clk = clk_register(NULL, &psc->hw);
453 	if (IS_ERR(clk))
454 		kfree(psc);
455 
456 	return &psc->hw;
457 }
458 
459 struct ep93xx_gate {
460 	unsigned int bit;
461 	const char *dev_id;
462 	const char *con_id;
463 };
464 
465 static struct ep93xx_gate ep93xx_uarts[] = {
466 	{EP93XX_SYSCON_DEVCFG_U1EN, "apb:uart1", NULL},
467 	{EP93XX_SYSCON_DEVCFG_U2EN, "apb:uart2", NULL},
468 	{EP93XX_SYSCON_DEVCFG_U3EN, "apb:uart3", NULL},
469 };
470 
471 static void __init ep93xx_uart_clock_init(void)
472 {
473 	unsigned int i;
474 	struct clk_hw *hw;
475 	u32 value;
476 	unsigned int clk_uart_div;
477 
478 	value = __raw_readl(EP93XX_SYSCON_PWRCNT);
479 	if (value & EP93XX_SYSCON_PWRCNT_UARTBAUD)
480 		clk_uart_div = 1;
481 	else
482 		clk_uart_div = 2;
483 
484 	hw = clk_hw_register_fixed_factor(NULL, "uart", "xtali", 0, 1, clk_uart_div);
485 
486 	/* parenting uart gate clocks to uart clock */
487 	for (i = 0; i < ARRAY_SIZE(ep93xx_uarts); i++) {
488 		hw = ep93xx_clk_register_gate(ep93xx_uarts[i].dev_id,
489 					"uart",
490 					EP93XX_SYSCON_DEVCFG,
491 					ep93xx_uarts[i].bit);
492 
493 		clk_hw_register_clkdev(hw, NULL, ep93xx_uarts[i].dev_id);
494 	}
495 }
496 
497 static struct ep93xx_gate ep93xx_dmas[] = {
498 	{EP93XX_SYSCON_PWRCNT_DMA_M2P0, NULL, "m2p0"},
499 	{EP93XX_SYSCON_PWRCNT_DMA_M2P1, NULL, "m2p1"},
500 	{EP93XX_SYSCON_PWRCNT_DMA_M2P2, NULL, "m2p2"},
501 	{EP93XX_SYSCON_PWRCNT_DMA_M2P3, NULL, "m2p3"},
502 	{EP93XX_SYSCON_PWRCNT_DMA_M2P4, NULL, "m2p4"},
503 	{EP93XX_SYSCON_PWRCNT_DMA_M2P5, NULL, "m2p5"},
504 	{EP93XX_SYSCON_PWRCNT_DMA_M2P6, NULL, "m2p6"},
505 	{EP93XX_SYSCON_PWRCNT_DMA_M2P7, NULL, "m2p7"},
506 	{EP93XX_SYSCON_PWRCNT_DMA_M2P8, NULL, "m2p8"},
507 	{EP93XX_SYSCON_PWRCNT_DMA_M2P9, NULL, "m2p9"},
508 	{EP93XX_SYSCON_PWRCNT_DMA_M2M0, NULL, "m2m0"},
509 	{EP93XX_SYSCON_PWRCNT_DMA_M2M1, NULL, "m2m1"},
510 };
511 
512 static void __init ep93xx_dma_clock_init(void)
513 {
514 	unsigned int i;
515 	struct clk_hw *hw;
516 	int ret;
517 
518 	for (i = 0; i < ARRAY_SIZE(ep93xx_dmas); i++) {
519 		hw = clk_hw_register_gate(NULL, ep93xx_dmas[i].con_id,
520 					"hclk", 0,
521 					EP93XX_SYSCON_PWRCNT,
522 					ep93xx_dmas[i].bit,
523 					0,
524 					&clk_lock);
525 
526 		ret = clk_hw_register_clkdev(hw, ep93xx_dmas[i].con_id, NULL);
527 		if (ret)
528 			pr_err("%s: failed to register lookup %s\n",
529 			       __func__, ep93xx_dmas[i].con_id);
530 	}
531 }
532 
533 static int __init ep93xx_clock_init(void)
534 {
535 	u32 value;
536 	struct clk_hw *hw;
537 	unsigned long clk_pll1_rate;
538 	unsigned long clk_f_rate;
539 	unsigned long clk_h_rate;
540 	unsigned long clk_p_rate;
541 	unsigned long clk_pll2_rate;
542 	unsigned int clk_f_div;
543 	unsigned int clk_h_div;
544 	unsigned int clk_p_div;
545 	unsigned int clk_usb_div;
546 	unsigned long clk_spi_div;
547 
548 	hw = clk_hw_register_fixed_rate(NULL, "xtali", NULL, 0, EP93XX_EXT_CLK_RATE);
549 	clk_hw_register_clkdev(hw, NULL, "xtali");
550 
551 	/* Determine the bootloader configured pll1 rate */
552 	value = __raw_readl(EP93XX_SYSCON_CLKSET1);
553 	if (!(value & EP93XX_SYSCON_CLKSET1_NBYP1))
554 		clk_pll1_rate = EP93XX_EXT_CLK_RATE;
555 	else
556 		clk_pll1_rate = calc_pll_rate(EP93XX_EXT_CLK_RATE, value);
557 
558 	hw = clk_hw_register_fixed_rate(NULL, "pll1", "xtali", 0, clk_pll1_rate);
559 	clk_hw_register_clkdev(hw, NULL, "pll1");
560 
561 	/* Initialize the pll1 derived clocks */
562 	clk_f_div = fclk_divisors[(value >> 25) & 0x7];
563 	clk_h_div = hclk_divisors[(value >> 20) & 0x7];
564 	clk_p_div = pclk_divisors[(value >> 18) & 0x3];
565 
566 	hw = clk_hw_register_fixed_factor(NULL, "fclk", "pll1", 0, 1, clk_f_div);
567 	clk_f_rate = clk_get_rate(hw->clk);
568 	hw = clk_hw_register_fixed_factor(NULL, "hclk", "pll1", 0, 1, clk_h_div);
569 	clk_h_rate = clk_get_rate(hw->clk);
570 	hw = clk_hw_register_fixed_factor(NULL, "pclk", "hclk", 0, 1, clk_p_div);
571 	clk_p_rate = clk_get_rate(hw->clk);
572 
573 	clk_hw_register_clkdev(hw, "apb_pclk", NULL);
574 
575 	ep93xx_dma_clock_init();
576 
577 	/* Determine the bootloader configured pll2 rate */
578 	value = __raw_readl(EP93XX_SYSCON_CLKSET2);
579 	if (!(value & EP93XX_SYSCON_CLKSET2_NBYP2))
580 		clk_pll2_rate = EP93XX_EXT_CLK_RATE;
581 	else if (value & EP93XX_SYSCON_CLKSET2_PLL2_EN)
582 		clk_pll2_rate = calc_pll_rate(EP93XX_EXT_CLK_RATE, value);
583 	else
584 		clk_pll2_rate = 0;
585 
586 	hw = clk_hw_register_fixed_rate(NULL, "pll2", "xtali", 0, clk_pll2_rate);
587 	clk_hw_register_clkdev(hw, NULL, "pll2");
588 
589 	/* Initialize the pll2 derived clocks */
590 	/*
591 	 * These four bits set the divide ratio between the PLL2
592 	 * output and the USB clock.
593 	 * 0000 - Divide by 1
594 	 * 0001 - Divide by 2
595 	 * 0010 - Divide by 3
596 	 * 0011 - Divide by 4
597 	 * 0100 - Divide by 5
598 	 * 0101 - Divide by 6
599 	 * 0110 - Divide by 7
600 	 * 0111 - Divide by 8
601 	 * 1000 - Divide by 9
602 	 * 1001 - Divide by 10
603 	 * 1010 - Divide by 11
604 	 * 1011 - Divide by 12
605 	 * 1100 - Divide by 13
606 	 * 1101 - Divide by 14
607 	 * 1110 - Divide by 15
608 	 * 1111 - Divide by 1
609 	 * On power-on-reset these bits are reset to 0000b.
610 	 */
611 	clk_usb_div = (((value >> 28) & 0xf) + 1);
612 	hw = clk_hw_register_fixed_factor(NULL, "usb_clk", "pll2", 0, 1, clk_usb_div);
613 	hw = clk_hw_register_gate(NULL, "ohci-platform",
614 				"usb_clk", 0,
615 				EP93XX_SYSCON_PWRCNT,
616 				EP93XX_SYSCON_PWRCNT_USH_EN,
617 				0,
618 				&clk_lock);
619 	clk_hw_register_clkdev(hw, NULL, "ohci-platform");
620 
621 	/*
622 	 * EP93xx SSP clock rate was doubled in version E2. For more information
623 	 * see:
624 	 *     http://www.cirrus.com/en/pubs/appNote/AN273REV4.pdf
625 	 */
626 	clk_spi_div = 1;
627 	if (ep93xx_chip_revision() < EP93XX_CHIP_REV_E2)
628 		clk_spi_div = 2;
629 	hw = clk_hw_register_fixed_factor(NULL, "ep93xx-spi.0", "xtali", 0, 1, clk_spi_div);
630 	clk_hw_register_clkdev(hw, NULL, "ep93xx-spi.0");
631 
632 	/* pwm clock */
633 	hw = clk_hw_register_fixed_factor(NULL, "pwm_clk", "xtali", 0, 1, 1);
634 	clk_hw_register_clkdev(hw, "pwm_clk", NULL);
635 
636 	pr_info("PLL1 running at %ld MHz, PLL2 at %ld MHz\n",
637 		clk_pll1_rate / 1000000, clk_pll2_rate / 1000000);
638 	pr_info("FCLK %ld MHz, HCLK %ld MHz, PCLK %ld MHz\n",
639 		clk_f_rate / 1000000, clk_h_rate / 1000000,
640 		clk_p_rate / 1000000);
641 
642 	ep93xx_uart_clock_init();
643 
644 	/* touchscreen/adc clock */
645 	hw = clk_hw_register_div("ep93xx-adc",
646 				"xtali",
647 				EP93XX_SYSCON_KEYTCHCLKDIV,
648 				EP93XX_SYSCON_KEYTCHCLKDIV_TSEN,
649 				EP93XX_SYSCON_KEYTCHCLKDIV_ADIV,
650 				1,
651 				adc_divisors,
652 				ARRAY_SIZE(adc_divisors));
653 
654 	clk_hw_register_clkdev(hw, NULL, "ep93xx-adc");
655 
656 	/* keypad clock */
657 	hw = clk_hw_register_div("ep93xx-keypad",
658 				"xtali",
659 				EP93XX_SYSCON_KEYTCHCLKDIV,
660 				EP93XX_SYSCON_KEYTCHCLKDIV_KEN,
661 				EP93XX_SYSCON_KEYTCHCLKDIV_KDIV,
662 				1,
663 				adc_divisors,
664 				ARRAY_SIZE(adc_divisors));
665 
666 	clk_hw_register_clkdev(hw, NULL, "ep93xx-keypad");
667 
668 	/* On reset PDIV and VDIV is set to zero, while PDIV zero
669 	 * means clock disable, VDIV shouldn't be zero.
670 	 * So i set both dividers to minimum.
671 	 */
672 	/* ENA - Enable CLK divider. */
673 	/* PDIV - 00 - Disable clock */
674 	/* VDIV - at least 2 */
675 	/* Check and enable video clk registers */
676 	value = __raw_readl(EP93XX_SYSCON_VIDCLKDIV);
677 	value |= (1 << EP93XX_SYSCON_CLKDIV_PDIV_SHIFT) | 2;
678 	ep93xx_syscon_swlocked_write(value, EP93XX_SYSCON_VIDCLKDIV);
679 
680 	/* check and enable i2s clk registers */
681 	value = __raw_readl(EP93XX_SYSCON_I2SCLKDIV);
682 	value |= (1 << EP93XX_SYSCON_CLKDIV_PDIV_SHIFT) | 2;
683 	ep93xx_syscon_swlocked_write(value, EP93XX_SYSCON_I2SCLKDIV);
684 
685 	/* video clk */
686 	hw = clk_hw_register_ddiv("ep93xx-fb",
687 				EP93XX_SYSCON_VIDCLKDIV,
688 				EP93XX_SYSCON_CLKDIV_ENABLE);
689 
690 	clk_hw_register_clkdev(hw, NULL, "ep93xx-fb");
691 
692 	/* i2s clk */
693 	hw = clk_hw_register_ddiv("mclk",
694 				EP93XX_SYSCON_I2SCLKDIV,
695 				EP93XX_SYSCON_CLKDIV_ENABLE);
696 
697 	clk_hw_register_clkdev(hw, "mclk", "ep93xx-i2s");
698 
699 	/* i2s sclk */
700 #define EP93XX_I2SCLKDIV_SDIV_SHIFT	16
701 #define EP93XX_I2SCLKDIV_SDIV_WIDTH	1
702 	hw = clk_hw_register_div("sclk",
703 				"mclk",
704 				EP93XX_SYSCON_I2SCLKDIV,
705 				EP93XX_SYSCON_I2SCLKDIV_SENA,
706 				EP93XX_I2SCLKDIV_SDIV_SHIFT,
707 				EP93XX_I2SCLKDIV_SDIV_WIDTH,
708 				sclk_divisors,
709 				ARRAY_SIZE(sclk_divisors));
710 
711 	clk_hw_register_clkdev(hw, "sclk", "ep93xx-i2s");
712 
713 	/* i2s lrclk */
714 #define EP93XX_I2SCLKDIV_LRDIV32_SHIFT	17
715 #define EP93XX_I2SCLKDIV_LRDIV32_WIDTH	3
716 	hw = clk_hw_register_div("lrclk",
717 				"sclk",
718 				EP93XX_SYSCON_I2SCLKDIV,
719 				EP93XX_SYSCON_I2SCLKDIV_SENA,
720 				EP93XX_I2SCLKDIV_LRDIV32_SHIFT,
721 				EP93XX_I2SCLKDIV_LRDIV32_WIDTH,
722 				lrclk_divisors,
723 				ARRAY_SIZE(lrclk_divisors));
724 
725 	clk_hw_register_clkdev(hw, "lrclk", "ep93xx-i2s");
726 
727 	return 0;
728 }
729 postcore_initcall(ep93xx_clock_init);
730