xref: /openbmc/linux/drivers/clk/imx/clk-pllv3.c (revision f20c7d91)
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  * @clk_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  *
40  * IMX PLL clock version 3, found on i.MX6 series.  Divider for pllv3
41  * is actually a multiplier, and always sits at bit 0.
42  */
43 struct clk_pllv3 {
44 	struct clk_hw	hw;
45 	void __iomem	*base;
46 	u32		power_bit;
47 	bool		powerup_set;
48 	u32		div_mask;
49 	u32		div_shift;
50 	unsigned long	ref_clock;
51 	u32		num_offset;
52 	u32		denom_offset;
53 };
54 
55 #define to_clk_pllv3(_hw) container_of(_hw, struct clk_pllv3, hw)
56 
57 static int clk_pllv3_wait_lock(struct clk_pllv3 *pll)
58 {
59 	u32 val = readl_relaxed(pll->base) & pll->power_bit;
60 
61 	/* No need to wait for lock when pll is not powered up */
62 	if ((pll->powerup_set && !val) || (!pll->powerup_set && val))
63 		return 0;
64 
65 	return readl_relaxed_poll_timeout(pll->base, val, val & BM_PLL_LOCK,
66 					  500, PLL_LOCK_TIMEOUT);
67 }
68 
69 static int clk_pllv3_prepare(struct clk_hw *hw)
70 {
71 	struct clk_pllv3 *pll = to_clk_pllv3(hw);
72 	u32 val;
73 
74 	val = readl_relaxed(pll->base);
75 	if (pll->powerup_set)
76 		val |= pll->power_bit;
77 	else
78 		val &= ~pll->power_bit;
79 	writel_relaxed(val, pll->base);
80 
81 	return clk_pllv3_wait_lock(pll);
82 }
83 
84 static void clk_pllv3_unprepare(struct clk_hw *hw)
85 {
86 	struct clk_pllv3 *pll = to_clk_pllv3(hw);
87 	u32 val;
88 
89 	val = readl_relaxed(pll->base);
90 	if (pll->powerup_set)
91 		val &= ~pll->power_bit;
92 	else
93 		val |= pll->power_bit;
94 	writel_relaxed(val, pll->base);
95 }
96 
97 static int clk_pllv3_is_prepared(struct clk_hw *hw)
98 {
99 	struct clk_pllv3 *pll = to_clk_pllv3(hw);
100 
101 	if (readl_relaxed(pll->base) & BM_PLL_LOCK)
102 		return 1;
103 
104 	return 0;
105 }
106 
107 static unsigned long clk_pllv3_recalc_rate(struct clk_hw *hw,
108 					   unsigned long parent_rate)
109 {
110 	struct clk_pllv3 *pll = to_clk_pllv3(hw);
111 	u32 div = (readl_relaxed(pll->base) >> pll->div_shift)  & pll->div_mask;
112 
113 	return (div == 1) ? parent_rate * 22 : parent_rate * 20;
114 }
115 
116 static long clk_pllv3_round_rate(struct clk_hw *hw, unsigned long rate,
117 				 unsigned long *prate)
118 {
119 	unsigned long parent_rate = *prate;
120 
121 	return (rate >= parent_rate * 22) ? parent_rate * 22 :
122 					    parent_rate * 20;
123 }
124 
125 static int clk_pllv3_set_rate(struct clk_hw *hw, unsigned long rate,
126 		unsigned long parent_rate)
127 {
128 	struct clk_pllv3 *pll = to_clk_pllv3(hw);
129 	u32 val, div;
130 
131 	if (rate == parent_rate * 22)
132 		div = 1;
133 	else if (rate == parent_rate * 20)
134 		div = 0;
135 	else
136 		return -EINVAL;
137 
138 	val = readl_relaxed(pll->base);
139 	val &= ~(pll->div_mask << pll->div_shift);
140 	val |= (div << pll->div_shift);
141 	writel_relaxed(val, pll->base);
142 
143 	return clk_pllv3_wait_lock(pll);
144 }
145 
146 static const struct clk_ops clk_pllv3_ops = {
147 	.prepare	= clk_pllv3_prepare,
148 	.unprepare	= clk_pllv3_unprepare,
149 	.is_prepared	= clk_pllv3_is_prepared,
150 	.recalc_rate	= clk_pllv3_recalc_rate,
151 	.round_rate	= clk_pllv3_round_rate,
152 	.set_rate	= clk_pllv3_set_rate,
153 };
154 
155 static unsigned long clk_pllv3_sys_recalc_rate(struct clk_hw *hw,
156 					       unsigned long parent_rate)
157 {
158 	struct clk_pllv3 *pll = to_clk_pllv3(hw);
159 	u32 div = readl_relaxed(pll->base) & pll->div_mask;
160 
161 	return parent_rate * div / 2;
162 }
163 
164 static long clk_pllv3_sys_round_rate(struct clk_hw *hw, unsigned long rate,
165 				     unsigned long *prate)
166 {
167 	unsigned long parent_rate = *prate;
168 	unsigned long min_rate = parent_rate * 54 / 2;
169 	unsigned long max_rate = parent_rate * 108 / 2;
170 	u32 div;
171 
172 	if (rate > max_rate)
173 		rate = max_rate;
174 	else if (rate < min_rate)
175 		rate = min_rate;
176 	div = rate * 2 / parent_rate;
177 
178 	return parent_rate * div / 2;
179 }
180 
181 static int clk_pllv3_sys_set_rate(struct clk_hw *hw, unsigned long rate,
182 		unsigned long parent_rate)
183 {
184 	struct clk_pllv3 *pll = to_clk_pllv3(hw);
185 	unsigned long min_rate = parent_rate * 54 / 2;
186 	unsigned long max_rate = parent_rate * 108 / 2;
187 	u32 val, div;
188 
189 	if (rate < min_rate || rate > max_rate)
190 		return -EINVAL;
191 
192 	div = rate * 2 / parent_rate;
193 	val = readl_relaxed(pll->base);
194 	val &= ~pll->div_mask;
195 	val |= div;
196 	writel_relaxed(val, pll->base);
197 
198 	return clk_pllv3_wait_lock(pll);
199 }
200 
201 static const struct clk_ops clk_pllv3_sys_ops = {
202 	.prepare	= clk_pllv3_prepare,
203 	.unprepare	= clk_pllv3_unprepare,
204 	.is_prepared	= clk_pllv3_is_prepared,
205 	.recalc_rate	= clk_pllv3_sys_recalc_rate,
206 	.round_rate	= clk_pllv3_sys_round_rate,
207 	.set_rate	= clk_pllv3_sys_set_rate,
208 };
209 
210 static unsigned long clk_pllv3_av_recalc_rate(struct clk_hw *hw,
211 					      unsigned long parent_rate)
212 {
213 	struct clk_pllv3 *pll = to_clk_pllv3(hw);
214 	u32 mfn = readl_relaxed(pll->base + pll->num_offset);
215 	u32 mfd = readl_relaxed(pll->base + pll->denom_offset);
216 	u32 div = readl_relaxed(pll->base) & pll->div_mask;
217 	u64 temp64 = (u64)parent_rate;
218 
219 	temp64 *= mfn;
220 	do_div(temp64, mfd);
221 
222 	return parent_rate * div + (unsigned long)temp64;
223 }
224 
225 static long clk_pllv3_av_round_rate(struct clk_hw *hw, unsigned long rate,
226 				    unsigned long *prate)
227 {
228 	unsigned long parent_rate = *prate;
229 	unsigned long min_rate = parent_rate * 27;
230 	unsigned long max_rate = parent_rate * 54;
231 	u32 div;
232 	u32 mfn, mfd = 1000000;
233 	u32 max_mfd = 0x3FFFFFFF;
234 	u64 temp64;
235 
236 	if (rate > max_rate)
237 		rate = max_rate;
238 	else if (rate < min_rate)
239 		rate = min_rate;
240 
241 	if (parent_rate <= max_mfd)
242 		mfd = parent_rate;
243 
244 	div = rate / parent_rate;
245 	temp64 = (u64) (rate - div * parent_rate);
246 	temp64 *= mfd;
247 	do_div(temp64, parent_rate);
248 	mfn = temp64;
249 
250 	temp64 = (u64)parent_rate;
251 	temp64 *= mfn;
252 	do_div(temp64, mfd);
253 
254 	return parent_rate * div + (unsigned long)temp64;
255 }
256 
257 static int clk_pllv3_av_set_rate(struct clk_hw *hw, unsigned long rate,
258 		unsigned long parent_rate)
259 {
260 	struct clk_pllv3 *pll = to_clk_pllv3(hw);
261 	unsigned long min_rate = parent_rate * 27;
262 	unsigned long max_rate = parent_rate * 54;
263 	u32 val, div;
264 	u32 mfn, mfd = 1000000;
265 	u32 max_mfd = 0x3FFFFFFF;
266 	u64 temp64;
267 
268 	if (rate < min_rate || rate > max_rate)
269 		return -EINVAL;
270 
271 	if (parent_rate <= max_mfd)
272 		mfd = parent_rate;
273 
274 	div = rate / parent_rate;
275 	temp64 = (u64) (rate - div * parent_rate);
276 	temp64 *= mfd;
277 	do_div(temp64, parent_rate);
278 	mfn = temp64;
279 
280 	val = readl_relaxed(pll->base);
281 	val &= ~pll->div_mask;
282 	val |= div;
283 	writel_relaxed(val, pll->base);
284 	writel_relaxed(mfn, pll->base + pll->num_offset);
285 	writel_relaxed(mfd, pll->base + pll->denom_offset);
286 
287 	return clk_pllv3_wait_lock(pll);
288 }
289 
290 static const struct clk_ops clk_pllv3_av_ops = {
291 	.prepare	= clk_pllv3_prepare,
292 	.unprepare	= clk_pllv3_unprepare,
293 	.is_prepared	= clk_pllv3_is_prepared,
294 	.recalc_rate	= clk_pllv3_av_recalc_rate,
295 	.round_rate	= clk_pllv3_av_round_rate,
296 	.set_rate	= clk_pllv3_av_set_rate,
297 };
298 
299 struct clk_pllv3_vf610_mf {
300 	u32 mfi;	/* integer part, can be 20 or 22 */
301 	u32 mfn;	/* numerator, 30-bit value */
302 	u32 mfd;	/* denominator, 30-bit value, must be less than mfn */
303 };
304 
305 static unsigned long clk_pllv3_vf610_mf_to_rate(unsigned long parent_rate,
306 		struct clk_pllv3_vf610_mf mf)
307 {
308 	u64 temp64;
309 
310 	temp64 = parent_rate;
311 	temp64 *= mf.mfn;
312 	do_div(temp64, mf.mfd);
313 
314 	return (parent_rate * mf.mfi) + temp64;
315 }
316 
317 static struct clk_pllv3_vf610_mf clk_pllv3_vf610_rate_to_mf(
318 		unsigned long parent_rate, unsigned long rate)
319 {
320 	struct clk_pllv3_vf610_mf mf;
321 	u64 temp64;
322 
323 	mf.mfi = (rate >= 22 * parent_rate) ? 22 : 20;
324 	mf.mfd = 0x3fffffff;	/* use max supported value for best accuracy */
325 
326 	if (rate <= parent_rate * mf.mfi)
327 		mf.mfn = 0;
328 	else if (rate >= parent_rate * (mf.mfi + 1))
329 		mf.mfn = mf.mfd - 1;
330 	else {
331 		/* rate = parent_rate * (mfi + mfn/mfd) */
332 		temp64 = rate - parent_rate * mf.mfi;
333 		temp64 *= mf.mfd;
334 		do_div(temp64, parent_rate);
335 		mf.mfn = temp64;
336 	}
337 
338 	return mf;
339 }
340 
341 static unsigned long clk_pllv3_vf610_recalc_rate(struct clk_hw *hw,
342 					      unsigned long parent_rate)
343 {
344 	struct clk_pllv3 *pll = to_clk_pllv3(hw);
345 	struct clk_pllv3_vf610_mf mf;
346 
347 	mf.mfn = readl_relaxed(pll->base + pll->num_offset);
348 	mf.mfd = readl_relaxed(pll->base + pll->denom_offset);
349 	mf.mfi = (readl_relaxed(pll->base) & pll->div_mask) ? 22 : 20;
350 
351 	return clk_pllv3_vf610_mf_to_rate(parent_rate, mf);
352 }
353 
354 static long clk_pllv3_vf610_round_rate(struct clk_hw *hw, unsigned long rate,
355 				    unsigned long *prate)
356 {
357 	struct clk_pllv3_vf610_mf mf = clk_pllv3_vf610_rate_to_mf(*prate, rate);
358 
359 	return clk_pllv3_vf610_mf_to_rate(*prate, mf);
360 }
361 
362 static int clk_pllv3_vf610_set_rate(struct clk_hw *hw, unsigned long rate,
363 		unsigned long parent_rate)
364 {
365 	struct clk_pllv3 *pll = to_clk_pllv3(hw);
366 	struct clk_pllv3_vf610_mf mf =
367 			clk_pllv3_vf610_rate_to_mf(parent_rate, rate);
368 	u32 val;
369 
370 	val = readl_relaxed(pll->base);
371 	if (mf.mfi == 20)
372 		val &= ~pll->div_mask;	/* clear bit for mfi=20 */
373 	else
374 		val |= pll->div_mask;	/* set bit for mfi=22 */
375 	writel_relaxed(val, pll->base);
376 
377 	writel_relaxed(mf.mfn, pll->base + pll->num_offset);
378 	writel_relaxed(mf.mfd, pll->base + pll->denom_offset);
379 
380 	return clk_pllv3_wait_lock(pll);
381 }
382 
383 static const struct clk_ops clk_pllv3_vf610_ops = {
384 	.prepare	= clk_pllv3_prepare,
385 	.unprepare	= clk_pllv3_unprepare,
386 	.is_prepared	= clk_pllv3_is_prepared,
387 	.recalc_rate	= clk_pllv3_vf610_recalc_rate,
388 	.round_rate	= clk_pllv3_vf610_round_rate,
389 	.set_rate	= clk_pllv3_vf610_set_rate,
390 };
391 
392 static unsigned long clk_pllv3_enet_recalc_rate(struct clk_hw *hw,
393 						unsigned long parent_rate)
394 {
395 	struct clk_pllv3 *pll = to_clk_pllv3(hw);
396 
397 	return pll->ref_clock;
398 }
399 
400 static const struct clk_ops clk_pllv3_enet_ops = {
401 	.prepare	= clk_pllv3_prepare,
402 	.unprepare	= clk_pllv3_unprepare,
403 	.is_prepared	= clk_pllv3_is_prepared,
404 	.recalc_rate	= clk_pllv3_enet_recalc_rate,
405 };
406 
407 struct clk_hw *imx_clk_hw_pllv3(enum imx_pllv3_type type, const char *name,
408 			  const char *parent_name, void __iomem *base,
409 			  u32 div_mask)
410 {
411 	struct clk_pllv3 *pll;
412 	const struct clk_ops *ops;
413 	struct clk_hw *hw;
414 	struct clk_init_data init;
415 	int ret;
416 
417 	pll = kzalloc(sizeof(*pll), GFP_KERNEL);
418 	if (!pll)
419 		return ERR_PTR(-ENOMEM);
420 
421 	pll->power_bit = BM_PLL_POWER;
422 	pll->num_offset = PLL_NUM_OFFSET;
423 	pll->denom_offset = PLL_DENOM_OFFSET;
424 
425 	switch (type) {
426 	case IMX_PLLV3_SYS:
427 		ops = &clk_pllv3_sys_ops;
428 		break;
429 	case IMX_PLLV3_SYS_VF610:
430 		ops = &clk_pllv3_vf610_ops;
431 		pll->num_offset = PLL_VF610_NUM_OFFSET;
432 		pll->denom_offset = PLL_VF610_DENOM_OFFSET;
433 		break;
434 	case IMX_PLLV3_USB_VF610:
435 		pll->div_shift = 1;
436 		/* fall through */
437 	case IMX_PLLV3_USB:
438 		ops = &clk_pllv3_ops;
439 		pll->powerup_set = true;
440 		break;
441 	case IMX_PLLV3_AV_IMX7:
442 		pll->num_offset = PLL_IMX7_NUM_OFFSET;
443 		pll->denom_offset = PLL_IMX7_DENOM_OFFSET;
444 		/* fall through */
445 	case IMX_PLLV3_AV:
446 		ops = &clk_pllv3_av_ops;
447 		break;
448 	case IMX_PLLV3_ENET_IMX7:
449 		pll->power_bit = IMX7_ENET_PLL_POWER;
450 		pll->ref_clock = 1000000000;
451 		ops = &clk_pllv3_enet_ops;
452 		break;
453 	case IMX_PLLV3_ENET:
454 		pll->ref_clock = 500000000;
455 		ops = &clk_pllv3_enet_ops;
456 		break;
457 	case IMX_PLLV3_DDR_IMX7:
458 		pll->power_bit = IMX7_DDR_PLL_POWER;
459 		pll->num_offset = PLL_IMX7_NUM_OFFSET;
460 		pll->denom_offset = PLL_IMX7_DENOM_OFFSET;
461 		ops = &clk_pllv3_av_ops;
462 		break;
463 	default:
464 		ops = &clk_pllv3_ops;
465 	}
466 	pll->base = base;
467 	pll->div_mask = div_mask;
468 
469 	init.name = name;
470 	init.ops = ops;
471 	init.flags = 0;
472 	init.parent_names = &parent_name;
473 	init.num_parents = 1;
474 
475 	pll->hw.init = &init;
476 	hw = &pll->hw;
477 
478 	ret = clk_hw_register(NULL, hw);
479 	if (ret) {
480 		kfree(pll);
481 		return ERR_PTR(ret);
482 	}
483 
484 	return hw;
485 }
486