xref: /openbmc/linux/drivers/clk/imx/clk-pllv3.c (revision 6c33a6f4)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * Copyright 2012 Freescale Semiconductor, Inc.
4  * Copyright 2012 Linaro Ltd.
5  */
6 
7 #include <linux/clk-provider.h>
8 #include <linux/delay.h>
9 #include <linux/io.h>
10 #include <linux/slab.h>
11 #include <linux/jiffies.h>
12 #include <linux/err.h>
13 #include "clk.h"
14 
15 #define PLL_NUM_OFFSET		0x10
16 #define PLL_DENOM_OFFSET	0x20
17 #define PLL_IMX7_NUM_OFFSET	0x20
18 #define PLL_IMX7_DENOM_OFFSET	0x30
19 
20 #define PLL_VF610_NUM_OFFSET	0x20
21 #define PLL_VF610_DENOM_OFFSET	0x30
22 
23 #define BM_PLL_POWER		(0x1 << 12)
24 #define BM_PLL_LOCK		(0x1 << 31)
25 #define IMX7_ENET_PLL_POWER	(0x1 << 5)
26 #define IMX7_DDR_PLL_POWER	(0x1 << 20)
27 
28 /**
29  * struct clk_pllv3 - IMX PLL clock version 3
30  * @clk_hw:	 clock source
31  * @base:	 base address of PLL registers
32  * @power_bit:	 pll power bit mask
33  * @powerup_set: set power_bit to power up the PLL
34  * @div_mask:	 mask of divider bits
35  * @div_shift:	 shift of divider bits
36  *
37  * IMX PLL clock version 3, found on i.MX6 series.  Divider for pllv3
38  * is actually a multiplier, and always sits at bit 0.
39  */
40 struct clk_pllv3 {
41 	struct clk_hw	hw;
42 	void __iomem	*base;
43 	u32		power_bit;
44 	bool		powerup_set;
45 	u32		div_mask;
46 	u32		div_shift;
47 	unsigned long	ref_clock;
48 	u32		num_offset;
49 	u32		denom_offset;
50 };
51 
52 #define to_clk_pllv3(_hw) container_of(_hw, struct clk_pllv3, hw)
53 
54 static int clk_pllv3_wait_lock(struct clk_pllv3 *pll)
55 {
56 	unsigned long timeout = jiffies + msecs_to_jiffies(10);
57 	u32 val = readl_relaxed(pll->base) & pll->power_bit;
58 
59 	/* No need to wait for lock when pll is not powered up */
60 	if ((pll->powerup_set && !val) || (!pll->powerup_set && val))
61 		return 0;
62 
63 	/* Wait for PLL to lock */
64 	do {
65 		if (readl_relaxed(pll->base) & BM_PLL_LOCK)
66 			break;
67 		if (time_after(jiffies, timeout))
68 			break;
69 		usleep_range(50, 500);
70 	} while (1);
71 
72 	return readl_relaxed(pll->base) & BM_PLL_LOCK ? 0 : -ETIMEDOUT;
73 }
74 
75 static int clk_pllv3_prepare(struct clk_hw *hw)
76 {
77 	struct clk_pllv3 *pll = to_clk_pllv3(hw);
78 	u32 val;
79 
80 	val = readl_relaxed(pll->base);
81 	if (pll->powerup_set)
82 		val |= pll->power_bit;
83 	else
84 		val &= ~pll->power_bit;
85 	writel_relaxed(val, pll->base);
86 
87 	return clk_pllv3_wait_lock(pll);
88 }
89 
90 static void clk_pllv3_unprepare(struct clk_hw *hw)
91 {
92 	struct clk_pllv3 *pll = to_clk_pllv3(hw);
93 	u32 val;
94 
95 	val = readl_relaxed(pll->base);
96 	if (pll->powerup_set)
97 		val &= ~pll->power_bit;
98 	else
99 		val |= pll->power_bit;
100 	writel_relaxed(val, pll->base);
101 }
102 
103 static int clk_pllv3_is_prepared(struct clk_hw *hw)
104 {
105 	struct clk_pllv3 *pll = to_clk_pllv3(hw);
106 
107 	if (readl_relaxed(pll->base) & BM_PLL_LOCK)
108 		return 1;
109 
110 	return 0;
111 }
112 
113 static unsigned long clk_pllv3_recalc_rate(struct clk_hw *hw,
114 					   unsigned long parent_rate)
115 {
116 	struct clk_pllv3 *pll = to_clk_pllv3(hw);
117 	u32 div = (readl_relaxed(pll->base) >> pll->div_shift)  & pll->div_mask;
118 
119 	return (div == 1) ? parent_rate * 22 : parent_rate * 20;
120 }
121 
122 static long clk_pllv3_round_rate(struct clk_hw *hw, unsigned long rate,
123 				 unsigned long *prate)
124 {
125 	unsigned long parent_rate = *prate;
126 
127 	return (rate >= parent_rate * 22) ? parent_rate * 22 :
128 					    parent_rate * 20;
129 }
130 
131 static int clk_pllv3_set_rate(struct clk_hw *hw, unsigned long rate,
132 		unsigned long parent_rate)
133 {
134 	struct clk_pllv3 *pll = to_clk_pllv3(hw);
135 	u32 val, div;
136 
137 	if (rate == parent_rate * 22)
138 		div = 1;
139 	else if (rate == parent_rate * 20)
140 		div = 0;
141 	else
142 		return -EINVAL;
143 
144 	val = readl_relaxed(pll->base);
145 	val &= ~(pll->div_mask << pll->div_shift);
146 	val |= (div << pll->div_shift);
147 	writel_relaxed(val, pll->base);
148 
149 	return clk_pllv3_wait_lock(pll);
150 }
151 
152 static const struct clk_ops clk_pllv3_ops = {
153 	.prepare	= clk_pllv3_prepare,
154 	.unprepare	= clk_pllv3_unprepare,
155 	.is_prepared	= clk_pllv3_is_prepared,
156 	.recalc_rate	= clk_pllv3_recalc_rate,
157 	.round_rate	= clk_pllv3_round_rate,
158 	.set_rate	= clk_pllv3_set_rate,
159 };
160 
161 static unsigned long clk_pllv3_sys_recalc_rate(struct clk_hw *hw,
162 					       unsigned long parent_rate)
163 {
164 	struct clk_pllv3 *pll = to_clk_pllv3(hw);
165 	u32 div = readl_relaxed(pll->base) & pll->div_mask;
166 
167 	return parent_rate * div / 2;
168 }
169 
170 static long clk_pllv3_sys_round_rate(struct clk_hw *hw, unsigned long rate,
171 				     unsigned long *prate)
172 {
173 	unsigned long parent_rate = *prate;
174 	unsigned long min_rate = parent_rate * 54 / 2;
175 	unsigned long max_rate = parent_rate * 108 / 2;
176 	u32 div;
177 
178 	if (rate > max_rate)
179 		rate = max_rate;
180 	else if (rate < min_rate)
181 		rate = min_rate;
182 	div = rate * 2 / parent_rate;
183 
184 	return parent_rate * div / 2;
185 }
186 
187 static int clk_pllv3_sys_set_rate(struct clk_hw *hw, unsigned long rate,
188 		unsigned long parent_rate)
189 {
190 	struct clk_pllv3 *pll = to_clk_pllv3(hw);
191 	unsigned long min_rate = parent_rate * 54 / 2;
192 	unsigned long max_rate = parent_rate * 108 / 2;
193 	u32 val, div;
194 
195 	if (rate < min_rate || rate > max_rate)
196 		return -EINVAL;
197 
198 	div = rate * 2 / parent_rate;
199 	val = readl_relaxed(pll->base);
200 	val &= ~pll->div_mask;
201 	val |= div;
202 	writel_relaxed(val, pll->base);
203 
204 	return clk_pllv3_wait_lock(pll);
205 }
206 
207 static const struct clk_ops clk_pllv3_sys_ops = {
208 	.prepare	= clk_pllv3_prepare,
209 	.unprepare	= clk_pllv3_unprepare,
210 	.is_prepared	= clk_pllv3_is_prepared,
211 	.recalc_rate	= clk_pllv3_sys_recalc_rate,
212 	.round_rate	= clk_pllv3_sys_round_rate,
213 	.set_rate	= clk_pllv3_sys_set_rate,
214 };
215 
216 static unsigned long clk_pllv3_av_recalc_rate(struct clk_hw *hw,
217 					      unsigned long parent_rate)
218 {
219 	struct clk_pllv3 *pll = to_clk_pllv3(hw);
220 	u32 mfn = readl_relaxed(pll->base + pll->num_offset);
221 	u32 mfd = readl_relaxed(pll->base + pll->denom_offset);
222 	u32 div = readl_relaxed(pll->base) & pll->div_mask;
223 	u64 temp64 = (u64)parent_rate;
224 
225 	temp64 *= mfn;
226 	do_div(temp64, mfd);
227 
228 	return parent_rate * div + (unsigned long)temp64;
229 }
230 
231 static long clk_pllv3_av_round_rate(struct clk_hw *hw, unsigned long rate,
232 				    unsigned long *prate)
233 {
234 	unsigned long parent_rate = *prate;
235 	unsigned long min_rate = parent_rate * 27;
236 	unsigned long max_rate = parent_rate * 54;
237 	u32 div;
238 	u32 mfn, mfd = 1000000;
239 	u32 max_mfd = 0x3FFFFFFF;
240 	u64 temp64;
241 
242 	if (rate > max_rate)
243 		rate = max_rate;
244 	else if (rate < min_rate)
245 		rate = min_rate;
246 
247 	if (parent_rate <= max_mfd)
248 		mfd = parent_rate;
249 
250 	div = rate / parent_rate;
251 	temp64 = (u64) (rate - div * parent_rate);
252 	temp64 *= mfd;
253 	do_div(temp64, parent_rate);
254 	mfn = temp64;
255 
256 	temp64 = (u64)parent_rate;
257 	temp64 *= mfn;
258 	do_div(temp64, mfd);
259 
260 	return parent_rate * div + (unsigned long)temp64;
261 }
262 
263 static int clk_pllv3_av_set_rate(struct clk_hw *hw, unsigned long rate,
264 		unsigned long parent_rate)
265 {
266 	struct clk_pllv3 *pll = to_clk_pllv3(hw);
267 	unsigned long min_rate = parent_rate * 27;
268 	unsigned long max_rate = parent_rate * 54;
269 	u32 val, div;
270 	u32 mfn, mfd = 1000000;
271 	u32 max_mfd = 0x3FFFFFFF;
272 	u64 temp64;
273 
274 	if (rate < min_rate || rate > max_rate)
275 		return -EINVAL;
276 
277 	if (parent_rate <= max_mfd)
278 		mfd = parent_rate;
279 
280 	div = rate / parent_rate;
281 	temp64 = (u64) (rate - div * parent_rate);
282 	temp64 *= mfd;
283 	do_div(temp64, parent_rate);
284 	mfn = temp64;
285 
286 	val = readl_relaxed(pll->base);
287 	val &= ~pll->div_mask;
288 	val |= div;
289 	writel_relaxed(val, pll->base);
290 	writel_relaxed(mfn, pll->base + pll->num_offset);
291 	writel_relaxed(mfd, pll->base + pll->denom_offset);
292 
293 	return clk_pllv3_wait_lock(pll);
294 }
295 
296 static const struct clk_ops clk_pllv3_av_ops = {
297 	.prepare	= clk_pllv3_prepare,
298 	.unprepare	= clk_pllv3_unprepare,
299 	.is_prepared	= clk_pllv3_is_prepared,
300 	.recalc_rate	= clk_pllv3_av_recalc_rate,
301 	.round_rate	= clk_pllv3_av_round_rate,
302 	.set_rate	= clk_pllv3_av_set_rate,
303 };
304 
305 struct clk_pllv3_vf610_mf {
306 	u32 mfi;	/* integer part, can be 20 or 22 */
307 	u32 mfn;	/* numerator, 30-bit value */
308 	u32 mfd;	/* denominator, 30-bit value, must be less than mfn */
309 };
310 
311 static unsigned long clk_pllv3_vf610_mf_to_rate(unsigned long parent_rate,
312 		struct clk_pllv3_vf610_mf mf)
313 {
314 	u64 temp64;
315 
316 	temp64 = parent_rate;
317 	temp64 *= mf.mfn;
318 	do_div(temp64, mf.mfd);
319 
320 	return (parent_rate * mf.mfi) + temp64;
321 }
322 
323 static struct clk_pllv3_vf610_mf clk_pllv3_vf610_rate_to_mf(
324 		unsigned long parent_rate, unsigned long rate)
325 {
326 	struct clk_pllv3_vf610_mf mf;
327 	u64 temp64;
328 
329 	mf.mfi = (rate >= 22 * parent_rate) ? 22 : 20;
330 	mf.mfd = 0x3fffffff;	/* use max supported value for best accuracy */
331 
332 	if (rate <= parent_rate * mf.mfi)
333 		mf.mfn = 0;
334 	else if (rate >= parent_rate * (mf.mfi + 1))
335 		mf.mfn = mf.mfd - 1;
336 	else {
337 		/* rate = parent_rate * (mfi + mfn/mfd) */
338 		temp64 = rate - parent_rate * mf.mfi;
339 		temp64 *= mf.mfd;
340 		do_div(temp64, parent_rate);
341 		mf.mfn = temp64;
342 	}
343 
344 	return mf;
345 }
346 
347 static unsigned long clk_pllv3_vf610_recalc_rate(struct clk_hw *hw,
348 					      unsigned long parent_rate)
349 {
350 	struct clk_pllv3 *pll = to_clk_pllv3(hw);
351 	struct clk_pllv3_vf610_mf mf;
352 
353 	mf.mfn = readl_relaxed(pll->base + pll->num_offset);
354 	mf.mfd = readl_relaxed(pll->base + pll->denom_offset);
355 	mf.mfi = (readl_relaxed(pll->base) & pll->div_mask) ? 22 : 20;
356 
357 	return clk_pllv3_vf610_mf_to_rate(parent_rate, mf);
358 }
359 
360 static long clk_pllv3_vf610_round_rate(struct clk_hw *hw, unsigned long rate,
361 				    unsigned long *prate)
362 {
363 	struct clk_pllv3_vf610_mf mf = clk_pllv3_vf610_rate_to_mf(*prate, rate);
364 
365 	return clk_pllv3_vf610_mf_to_rate(*prate, mf);
366 }
367 
368 static int clk_pllv3_vf610_set_rate(struct clk_hw *hw, unsigned long rate,
369 		unsigned long parent_rate)
370 {
371 	struct clk_pllv3 *pll = to_clk_pllv3(hw);
372 	struct clk_pllv3_vf610_mf mf =
373 			clk_pllv3_vf610_rate_to_mf(parent_rate, rate);
374 	u32 val;
375 
376 	val = readl_relaxed(pll->base);
377 	if (mf.mfi == 20)
378 		val &= ~pll->div_mask;	/* clear bit for mfi=20 */
379 	else
380 		val |= pll->div_mask;	/* set bit for mfi=22 */
381 	writel_relaxed(val, pll->base);
382 
383 	writel_relaxed(mf.mfn, pll->base + pll->num_offset);
384 	writel_relaxed(mf.mfd, pll->base + pll->denom_offset);
385 
386 	return clk_pllv3_wait_lock(pll);
387 }
388 
389 static const struct clk_ops clk_pllv3_vf610_ops = {
390 	.prepare	= clk_pllv3_prepare,
391 	.unprepare	= clk_pllv3_unprepare,
392 	.is_prepared	= clk_pllv3_is_prepared,
393 	.recalc_rate	= clk_pllv3_vf610_recalc_rate,
394 	.round_rate	= clk_pllv3_vf610_round_rate,
395 	.set_rate	= clk_pllv3_vf610_set_rate,
396 };
397 
398 static unsigned long clk_pllv3_enet_recalc_rate(struct clk_hw *hw,
399 						unsigned long parent_rate)
400 {
401 	struct clk_pllv3 *pll = to_clk_pllv3(hw);
402 
403 	return pll->ref_clock;
404 }
405 
406 static const struct clk_ops clk_pllv3_enet_ops = {
407 	.prepare	= clk_pllv3_prepare,
408 	.unprepare	= clk_pllv3_unprepare,
409 	.is_prepared	= clk_pllv3_is_prepared,
410 	.recalc_rate	= clk_pllv3_enet_recalc_rate,
411 };
412 
413 struct clk_hw *imx_clk_hw_pllv3(enum imx_pllv3_type type, const char *name,
414 			  const char *parent_name, void __iomem *base,
415 			  u32 div_mask)
416 {
417 	struct clk_pllv3 *pll;
418 	const struct clk_ops *ops;
419 	struct clk_hw *hw;
420 	struct clk_init_data init;
421 	int ret;
422 
423 	pll = kzalloc(sizeof(*pll), GFP_KERNEL);
424 	if (!pll)
425 		return ERR_PTR(-ENOMEM);
426 
427 	pll->power_bit = BM_PLL_POWER;
428 	pll->num_offset = PLL_NUM_OFFSET;
429 	pll->denom_offset = PLL_DENOM_OFFSET;
430 
431 	switch (type) {
432 	case IMX_PLLV3_SYS:
433 		ops = &clk_pllv3_sys_ops;
434 		break;
435 	case IMX_PLLV3_SYS_VF610:
436 		ops = &clk_pllv3_vf610_ops;
437 		pll->num_offset = PLL_VF610_NUM_OFFSET;
438 		pll->denom_offset = PLL_VF610_DENOM_OFFSET;
439 		break;
440 	case IMX_PLLV3_USB_VF610:
441 		pll->div_shift = 1;
442 		/* fall through */
443 	case IMX_PLLV3_USB:
444 		ops = &clk_pllv3_ops;
445 		pll->powerup_set = true;
446 		break;
447 	case IMX_PLLV3_AV_IMX7:
448 		pll->num_offset = PLL_IMX7_NUM_OFFSET;
449 		pll->denom_offset = PLL_IMX7_DENOM_OFFSET;
450 		/* fall through */
451 	case IMX_PLLV3_AV:
452 		ops = &clk_pllv3_av_ops;
453 		break;
454 	case IMX_PLLV3_ENET_IMX7:
455 		pll->power_bit = IMX7_ENET_PLL_POWER;
456 		pll->ref_clock = 1000000000;
457 		ops = &clk_pllv3_enet_ops;
458 		break;
459 	case IMX_PLLV3_ENET:
460 		pll->ref_clock = 500000000;
461 		ops = &clk_pllv3_enet_ops;
462 		break;
463 	case IMX_PLLV3_DDR_IMX7:
464 		pll->power_bit = IMX7_DDR_PLL_POWER;
465 		pll->num_offset = PLL_IMX7_NUM_OFFSET;
466 		pll->denom_offset = PLL_IMX7_DENOM_OFFSET;
467 		ops = &clk_pllv3_av_ops;
468 		break;
469 	default:
470 		ops = &clk_pllv3_ops;
471 	}
472 	pll->base = base;
473 	pll->div_mask = div_mask;
474 
475 	init.name = name;
476 	init.ops = ops;
477 	init.flags = 0;
478 	init.parent_names = &parent_name;
479 	init.num_parents = 1;
480 
481 	pll->hw.init = &init;
482 	hw = &pll->hw;
483 
484 	ret = clk_hw_register(NULL, hw);
485 	if (ret) {
486 		kfree(pll);
487 		return ERR_PTR(ret);
488 	}
489 
490 	return hw;
491 }
492