xref: /openbmc/linux/drivers/clk/imx/clk-pllv3.c (revision 842ed298)
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/iopoll.h>
11 #include <linux/slab.h>
12 #include <linux/jiffies.h>
13 #include <linux/err.h>
14 #include "clk.h"
15 
16 #define PLL_NUM_OFFSET		0x10
17 #define PLL_DENOM_OFFSET	0x20
18 #define PLL_IMX7_NUM_OFFSET	0x20
19 #define PLL_IMX7_DENOM_OFFSET	0x30
20 
21 #define PLL_VF610_NUM_OFFSET	0x20
22 #define PLL_VF610_DENOM_OFFSET	0x30
23 
24 #define BM_PLL_POWER		(0x1 << 12)
25 #define BM_PLL_LOCK		(0x1 << 31)
26 #define IMX7_ENET_PLL_POWER	(0x1 << 5)
27 #define IMX7_DDR_PLL_POWER	(0x1 << 20)
28 
29 #define PLL_LOCK_TIMEOUT	10000
30 
31 /**
32  * struct clk_pllv3 - IMX PLL clock version 3
33  * @hw:		clock source
34  * @base:	 base address of PLL registers
35  * @power_bit:	 pll power bit mask
36  * @powerup_set: set power_bit to power up the PLL
37  * @div_mask:	 mask of divider bits
38  * @div_shift:	 shift of divider bits
39  * @ref_clock:	reference clock rate
40  * @num_offset:	num register offset
41  * @denom_offset: denom register offset
42  *
43  * IMX PLL clock version 3, found on i.MX6 series.  Divider for pllv3
44  * is actually a multiplier, and always sits at bit 0.
45  */
46 struct clk_pllv3 {
47 	struct clk_hw	hw;
48 	void __iomem	*base;
49 	u32		power_bit;
50 	bool		powerup_set;
51 	u32		div_mask;
52 	u32		div_shift;
53 	unsigned long	ref_clock;
54 	u32		num_offset;
55 	u32		denom_offset;
56 };
57 
58 #define to_clk_pllv3(_hw) container_of(_hw, struct clk_pllv3, hw)
59 
60 static int clk_pllv3_wait_lock(struct clk_pllv3 *pll)
61 {
62 	u32 val = readl_relaxed(pll->base) & pll->power_bit;
63 
64 	/* No need to wait for lock when pll is not powered up */
65 	if ((pll->powerup_set && !val) || (!pll->powerup_set && val))
66 		return 0;
67 
68 	return readl_relaxed_poll_timeout(pll->base, val, val & BM_PLL_LOCK,
69 					  500, PLL_LOCK_TIMEOUT);
70 }
71 
72 static int clk_pllv3_prepare(struct clk_hw *hw)
73 {
74 	struct clk_pllv3 *pll = to_clk_pllv3(hw);
75 	u32 val;
76 
77 	val = readl_relaxed(pll->base);
78 	if (pll->powerup_set)
79 		val |= pll->power_bit;
80 	else
81 		val &= ~pll->power_bit;
82 	writel_relaxed(val, pll->base);
83 
84 	return clk_pllv3_wait_lock(pll);
85 }
86 
87 static void clk_pllv3_unprepare(struct clk_hw *hw)
88 {
89 	struct clk_pllv3 *pll = to_clk_pllv3(hw);
90 	u32 val;
91 
92 	val = readl_relaxed(pll->base);
93 	if (pll->powerup_set)
94 		val &= ~pll->power_bit;
95 	else
96 		val |= pll->power_bit;
97 	writel_relaxed(val, pll->base);
98 }
99 
100 static int clk_pllv3_is_prepared(struct clk_hw *hw)
101 {
102 	struct clk_pllv3 *pll = to_clk_pllv3(hw);
103 
104 	if (readl_relaxed(pll->base) & BM_PLL_LOCK)
105 		return 1;
106 
107 	return 0;
108 }
109 
110 static unsigned long clk_pllv3_recalc_rate(struct clk_hw *hw,
111 					   unsigned long parent_rate)
112 {
113 	struct clk_pllv3 *pll = to_clk_pllv3(hw);
114 	u32 div = (readl_relaxed(pll->base) >> pll->div_shift)  & pll->div_mask;
115 
116 	return (div == 1) ? parent_rate * 22 : parent_rate * 20;
117 }
118 
119 static long clk_pllv3_round_rate(struct clk_hw *hw, unsigned long rate,
120 				 unsigned long *prate)
121 {
122 	unsigned long parent_rate = *prate;
123 
124 	return (rate >= parent_rate * 22) ? parent_rate * 22 :
125 					    parent_rate * 20;
126 }
127 
128 static int clk_pllv3_set_rate(struct clk_hw *hw, unsigned long rate,
129 		unsigned long parent_rate)
130 {
131 	struct clk_pllv3 *pll = to_clk_pllv3(hw);
132 	u32 val, div;
133 
134 	if (rate == parent_rate * 22)
135 		div = 1;
136 	else if (rate == parent_rate * 20)
137 		div = 0;
138 	else
139 		return -EINVAL;
140 
141 	val = readl_relaxed(pll->base);
142 	val &= ~(pll->div_mask << pll->div_shift);
143 	val |= (div << pll->div_shift);
144 	writel_relaxed(val, pll->base);
145 
146 	return clk_pllv3_wait_lock(pll);
147 }
148 
149 static const struct clk_ops clk_pllv3_ops = {
150 	.prepare	= clk_pllv3_prepare,
151 	.unprepare	= clk_pllv3_unprepare,
152 	.is_prepared	= clk_pllv3_is_prepared,
153 	.recalc_rate	= clk_pllv3_recalc_rate,
154 	.round_rate	= clk_pllv3_round_rate,
155 	.set_rate	= clk_pllv3_set_rate,
156 };
157 
158 static unsigned long clk_pllv3_sys_recalc_rate(struct clk_hw *hw,
159 					       unsigned long parent_rate)
160 {
161 	struct clk_pllv3 *pll = to_clk_pllv3(hw);
162 	u32 div = readl_relaxed(pll->base) & pll->div_mask;
163 
164 	return parent_rate * div / 2;
165 }
166 
167 static long clk_pllv3_sys_round_rate(struct clk_hw *hw, unsigned long rate,
168 				     unsigned long *prate)
169 {
170 	unsigned long parent_rate = *prate;
171 	unsigned long min_rate = parent_rate * 54 / 2;
172 	unsigned long max_rate = parent_rate * 108 / 2;
173 	u32 div;
174 
175 	if (rate > max_rate)
176 		rate = max_rate;
177 	else if (rate < min_rate)
178 		rate = min_rate;
179 	div = rate * 2 / parent_rate;
180 
181 	return parent_rate * div / 2;
182 }
183 
184 static int clk_pllv3_sys_set_rate(struct clk_hw *hw, unsigned long rate,
185 		unsigned long parent_rate)
186 {
187 	struct clk_pllv3 *pll = to_clk_pllv3(hw);
188 	unsigned long min_rate = parent_rate * 54 / 2;
189 	unsigned long max_rate = parent_rate * 108 / 2;
190 	u32 val, div;
191 
192 	if (rate < min_rate || rate > max_rate)
193 		return -EINVAL;
194 
195 	div = rate * 2 / parent_rate;
196 	val = readl_relaxed(pll->base);
197 	val &= ~pll->div_mask;
198 	val |= div;
199 	writel_relaxed(val, pll->base);
200 
201 	return clk_pllv3_wait_lock(pll);
202 }
203 
204 static const struct clk_ops clk_pllv3_sys_ops = {
205 	.prepare	= clk_pllv3_prepare,
206 	.unprepare	= clk_pllv3_unprepare,
207 	.is_prepared	= clk_pllv3_is_prepared,
208 	.recalc_rate	= clk_pllv3_sys_recalc_rate,
209 	.round_rate	= clk_pllv3_sys_round_rate,
210 	.set_rate	= clk_pllv3_sys_set_rate,
211 };
212 
213 static unsigned long clk_pllv3_av_recalc_rate(struct clk_hw *hw,
214 					      unsigned long parent_rate)
215 {
216 	struct clk_pllv3 *pll = to_clk_pllv3(hw);
217 	u32 mfn = readl_relaxed(pll->base + pll->num_offset);
218 	u32 mfd = readl_relaxed(pll->base + pll->denom_offset);
219 	u32 div = readl_relaxed(pll->base) & pll->div_mask;
220 	u64 temp64 = (u64)parent_rate;
221 
222 	temp64 *= mfn;
223 	do_div(temp64, mfd);
224 
225 	return parent_rate * div + (unsigned long)temp64;
226 }
227 
228 static long clk_pllv3_av_round_rate(struct clk_hw *hw, unsigned long rate,
229 				    unsigned long *prate)
230 {
231 	unsigned long parent_rate = *prate;
232 	unsigned long min_rate = parent_rate * 27;
233 	unsigned long max_rate = parent_rate * 54;
234 	u32 div;
235 	u32 mfn, mfd = 1000000;
236 	u32 max_mfd = 0x3FFFFFFF;
237 	u64 temp64;
238 
239 	if (rate > max_rate)
240 		rate = max_rate;
241 	else if (rate < min_rate)
242 		rate = min_rate;
243 
244 	if (parent_rate <= max_mfd)
245 		mfd = parent_rate;
246 
247 	div = rate / parent_rate;
248 	temp64 = (u64) (rate - div * parent_rate);
249 	temp64 *= mfd;
250 	do_div(temp64, parent_rate);
251 	mfn = temp64;
252 
253 	temp64 = (u64)parent_rate;
254 	temp64 *= mfn;
255 	do_div(temp64, mfd);
256 
257 	return parent_rate * div + (unsigned long)temp64;
258 }
259 
260 static int clk_pllv3_av_set_rate(struct clk_hw *hw, unsigned long rate,
261 		unsigned long parent_rate)
262 {
263 	struct clk_pllv3 *pll = to_clk_pllv3(hw);
264 	unsigned long min_rate = parent_rate * 27;
265 	unsigned long max_rate = parent_rate * 54;
266 	u32 val, div;
267 	u32 mfn, mfd = 1000000;
268 	u32 max_mfd = 0x3FFFFFFF;
269 	u64 temp64;
270 
271 	if (rate < min_rate || rate > max_rate)
272 		return -EINVAL;
273 
274 	if (parent_rate <= max_mfd)
275 		mfd = parent_rate;
276 
277 	div = rate / parent_rate;
278 	temp64 = (u64) (rate - div * parent_rate);
279 	temp64 *= mfd;
280 	do_div(temp64, parent_rate);
281 	mfn = temp64;
282 
283 	val = readl_relaxed(pll->base);
284 	val &= ~pll->div_mask;
285 	val |= div;
286 	writel_relaxed(val, pll->base);
287 	writel_relaxed(mfn, pll->base + pll->num_offset);
288 	writel_relaxed(mfd, pll->base + pll->denom_offset);
289 
290 	return clk_pllv3_wait_lock(pll);
291 }
292 
293 static const struct clk_ops clk_pllv3_av_ops = {
294 	.prepare	= clk_pllv3_prepare,
295 	.unprepare	= clk_pllv3_unprepare,
296 	.is_prepared	= clk_pllv3_is_prepared,
297 	.recalc_rate	= clk_pllv3_av_recalc_rate,
298 	.round_rate	= clk_pllv3_av_round_rate,
299 	.set_rate	= clk_pllv3_av_set_rate,
300 };
301 
302 struct clk_pllv3_vf610_mf {
303 	u32 mfi;	/* integer part, can be 20 or 22 */
304 	u32 mfn;	/* numerator, 30-bit value */
305 	u32 mfd;	/* denominator, 30-bit value, must be less than mfn */
306 };
307 
308 static unsigned long clk_pllv3_vf610_mf_to_rate(unsigned long parent_rate,
309 		struct clk_pllv3_vf610_mf mf)
310 {
311 	u64 temp64;
312 
313 	temp64 = parent_rate;
314 	temp64 *= mf.mfn;
315 	do_div(temp64, mf.mfd);
316 
317 	return (parent_rate * mf.mfi) + temp64;
318 }
319 
320 static struct clk_pllv3_vf610_mf clk_pllv3_vf610_rate_to_mf(
321 		unsigned long parent_rate, unsigned long rate)
322 {
323 	struct clk_pllv3_vf610_mf mf;
324 	u64 temp64;
325 
326 	mf.mfi = (rate >= 22 * parent_rate) ? 22 : 20;
327 	mf.mfd = 0x3fffffff;	/* use max supported value for best accuracy */
328 
329 	if (rate <= parent_rate * mf.mfi)
330 		mf.mfn = 0;
331 	else if (rate >= parent_rate * (mf.mfi + 1))
332 		mf.mfn = mf.mfd - 1;
333 	else {
334 		/* rate = parent_rate * (mfi + mfn/mfd) */
335 		temp64 = rate - parent_rate * mf.mfi;
336 		temp64 *= mf.mfd;
337 		do_div(temp64, parent_rate);
338 		mf.mfn = temp64;
339 	}
340 
341 	return mf;
342 }
343 
344 static unsigned long clk_pllv3_vf610_recalc_rate(struct clk_hw *hw,
345 					      unsigned long parent_rate)
346 {
347 	struct clk_pllv3 *pll = to_clk_pllv3(hw);
348 	struct clk_pllv3_vf610_mf mf;
349 
350 	mf.mfn = readl_relaxed(pll->base + pll->num_offset);
351 	mf.mfd = readl_relaxed(pll->base + pll->denom_offset);
352 	mf.mfi = (readl_relaxed(pll->base) & pll->div_mask) ? 22 : 20;
353 
354 	return clk_pllv3_vf610_mf_to_rate(parent_rate, mf);
355 }
356 
357 static long clk_pllv3_vf610_round_rate(struct clk_hw *hw, unsigned long rate,
358 				    unsigned long *prate)
359 {
360 	struct clk_pllv3_vf610_mf mf = clk_pllv3_vf610_rate_to_mf(*prate, rate);
361 
362 	return clk_pllv3_vf610_mf_to_rate(*prate, mf);
363 }
364 
365 static int clk_pllv3_vf610_set_rate(struct clk_hw *hw, unsigned long rate,
366 		unsigned long parent_rate)
367 {
368 	struct clk_pllv3 *pll = to_clk_pllv3(hw);
369 	struct clk_pllv3_vf610_mf mf =
370 			clk_pllv3_vf610_rate_to_mf(parent_rate, rate);
371 	u32 val;
372 
373 	val = readl_relaxed(pll->base);
374 	if (mf.mfi == 20)
375 		val &= ~pll->div_mask;	/* clear bit for mfi=20 */
376 	else
377 		val |= pll->div_mask;	/* set bit for mfi=22 */
378 	writel_relaxed(val, pll->base);
379 
380 	writel_relaxed(mf.mfn, pll->base + pll->num_offset);
381 	writel_relaxed(mf.mfd, pll->base + pll->denom_offset);
382 
383 	return clk_pllv3_wait_lock(pll);
384 }
385 
386 static const struct clk_ops clk_pllv3_vf610_ops = {
387 	.prepare	= clk_pllv3_prepare,
388 	.unprepare	= clk_pllv3_unprepare,
389 	.is_prepared	= clk_pllv3_is_prepared,
390 	.recalc_rate	= clk_pllv3_vf610_recalc_rate,
391 	.round_rate	= clk_pllv3_vf610_round_rate,
392 	.set_rate	= clk_pllv3_vf610_set_rate,
393 };
394 
395 static unsigned long clk_pllv3_enet_recalc_rate(struct clk_hw *hw,
396 						unsigned long parent_rate)
397 {
398 	struct clk_pllv3 *pll = to_clk_pllv3(hw);
399 
400 	return pll->ref_clock;
401 }
402 
403 static const struct clk_ops clk_pllv3_enet_ops = {
404 	.prepare	= clk_pllv3_prepare,
405 	.unprepare	= clk_pllv3_unprepare,
406 	.is_prepared	= clk_pllv3_is_prepared,
407 	.recalc_rate	= clk_pllv3_enet_recalc_rate,
408 };
409 
410 struct clk_hw *imx_clk_hw_pllv3(enum imx_pllv3_type type, const char *name,
411 			  const char *parent_name, void __iomem *base,
412 			  u32 div_mask)
413 {
414 	struct clk_pllv3 *pll;
415 	const struct clk_ops *ops;
416 	struct clk_hw *hw;
417 	struct clk_init_data init;
418 	int ret;
419 
420 	pll = kzalloc(sizeof(*pll), GFP_KERNEL);
421 	if (!pll)
422 		return ERR_PTR(-ENOMEM);
423 
424 	pll->power_bit = BM_PLL_POWER;
425 	pll->num_offset = PLL_NUM_OFFSET;
426 	pll->denom_offset = PLL_DENOM_OFFSET;
427 
428 	switch (type) {
429 	case IMX_PLLV3_SYS:
430 		ops = &clk_pllv3_sys_ops;
431 		break;
432 	case IMX_PLLV3_SYS_VF610:
433 		ops = &clk_pllv3_vf610_ops;
434 		pll->num_offset = PLL_VF610_NUM_OFFSET;
435 		pll->denom_offset = PLL_VF610_DENOM_OFFSET;
436 		break;
437 	case IMX_PLLV3_USB_VF610:
438 		pll->div_shift = 1;
439 		fallthrough;
440 	case IMX_PLLV3_USB:
441 		ops = &clk_pllv3_ops;
442 		pll->powerup_set = true;
443 		break;
444 	case IMX_PLLV3_AV_IMX7:
445 		pll->num_offset = PLL_IMX7_NUM_OFFSET;
446 		pll->denom_offset = PLL_IMX7_DENOM_OFFSET;
447 		fallthrough;
448 	case IMX_PLLV3_AV:
449 		ops = &clk_pllv3_av_ops;
450 		break;
451 	case IMX_PLLV3_ENET_IMX7:
452 		pll->power_bit = IMX7_ENET_PLL_POWER;
453 		pll->ref_clock = 1000000000;
454 		ops = &clk_pllv3_enet_ops;
455 		break;
456 	case IMX_PLLV3_ENET:
457 		pll->ref_clock = 500000000;
458 		ops = &clk_pllv3_enet_ops;
459 		break;
460 	case IMX_PLLV3_DDR_IMX7:
461 		pll->power_bit = IMX7_DDR_PLL_POWER;
462 		pll->num_offset = PLL_IMX7_NUM_OFFSET;
463 		pll->denom_offset = PLL_IMX7_DENOM_OFFSET;
464 		ops = &clk_pllv3_av_ops;
465 		break;
466 	default:
467 		ops = &clk_pllv3_ops;
468 	}
469 	pll->base = base;
470 	pll->div_mask = div_mask;
471 
472 	init.name = name;
473 	init.ops = ops;
474 	init.flags = 0;
475 	init.parent_names = &parent_name;
476 	init.num_parents = 1;
477 
478 	pll->hw.init = &init;
479 	hw = &pll->hw;
480 
481 	ret = clk_hw_register(NULL, hw);
482 	if (ret) {
483 		kfree(pll);
484 		return ERR_PTR(ret);
485 	}
486 
487 	return hw;
488 }
489