xref: /openbmc/linux/drivers/clk/imx/clk-pllv3.c (revision 7ff836f0)
1 /*
2  * Copyright 2012 Freescale Semiconductor, Inc.
3  * Copyright 2012 Linaro Ltd.
4  *
5  * The code contained herein is licensed under the GNU General Public
6  * License. You may obtain a copy of the GNU General Public License
7  * Version 2 or later at the following locations:
8  *
9  * http://www.opensource.org/licenses/gpl-license.html
10  * http://www.gnu.org/copyleft/gpl.html
11  */
12 
13 #include <linux/clk-provider.h>
14 #include <linux/delay.h>
15 #include <linux/io.h>
16 #include <linux/slab.h>
17 #include <linux/jiffies.h>
18 #include <linux/err.h>
19 #include "clk.h"
20 
21 #define PLL_NUM_OFFSET		0x10
22 #define PLL_DENOM_OFFSET	0x20
23 #define PLL_IMX7_NUM_OFFSET	0x20
24 #define PLL_IMX7_DENOM_OFFSET	0x30
25 
26 #define PLL_VF610_NUM_OFFSET	0x20
27 #define PLL_VF610_DENOM_OFFSET	0x30
28 
29 #define BM_PLL_POWER		(0x1 << 12)
30 #define BM_PLL_LOCK		(0x1 << 31)
31 #define IMX7_ENET_PLL_POWER	(0x1 << 5)
32 #define IMX7_DDR_PLL_POWER	(0x1 << 20)
33 
34 /**
35  * struct clk_pllv3 - IMX PLL clock version 3
36  * @clk_hw:	 clock source
37  * @base:	 base address of PLL registers
38  * @power_bit:	 pll power bit mask
39  * @powerup_set: set power_bit to power up the PLL
40  * @div_mask:	 mask of divider bits
41  * @div_shift:	 shift of divider bits
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 	unsigned long timeout = jiffies + msecs_to_jiffies(10);
63 	u32 val = readl_relaxed(pll->base) & pll->power_bit;
64 
65 	/* No need to wait for lock when pll is not powered up */
66 	if ((pll->powerup_set && !val) || (!pll->powerup_set && val))
67 		return 0;
68 
69 	/* Wait for PLL to lock */
70 	do {
71 		if (readl_relaxed(pll->base) & BM_PLL_LOCK)
72 			break;
73 		if (time_after(jiffies, timeout))
74 			break;
75 		usleep_range(50, 500);
76 	} while (1);
77 
78 	return readl_relaxed(pll->base) & BM_PLL_LOCK ? 0 : -ETIMEDOUT;
79 }
80 
81 static int clk_pllv3_prepare(struct clk_hw *hw)
82 {
83 	struct clk_pllv3 *pll = to_clk_pllv3(hw);
84 	u32 val;
85 
86 	val = readl_relaxed(pll->base);
87 	if (pll->powerup_set)
88 		val |= pll->power_bit;
89 	else
90 		val &= ~pll->power_bit;
91 	writel_relaxed(val, pll->base);
92 
93 	return clk_pllv3_wait_lock(pll);
94 }
95 
96 static void clk_pllv3_unprepare(struct clk_hw *hw)
97 {
98 	struct clk_pllv3 *pll = to_clk_pllv3(hw);
99 	u32 val;
100 
101 	val = readl_relaxed(pll->base);
102 	if (pll->powerup_set)
103 		val &= ~pll->power_bit;
104 	else
105 		val |= pll->power_bit;
106 	writel_relaxed(val, pll->base);
107 }
108 
109 static int clk_pllv3_is_prepared(struct clk_hw *hw)
110 {
111 	struct clk_pllv3 *pll = to_clk_pllv3(hw);
112 
113 	if (readl_relaxed(pll->base) & BM_PLL_LOCK)
114 		return 1;
115 
116 	return 0;
117 }
118 
119 static unsigned long clk_pllv3_recalc_rate(struct clk_hw *hw,
120 					   unsigned long parent_rate)
121 {
122 	struct clk_pllv3 *pll = to_clk_pllv3(hw);
123 	u32 div = (readl_relaxed(pll->base) >> pll->div_shift)  & pll->div_mask;
124 
125 	return (div == 1) ? parent_rate * 22 : parent_rate * 20;
126 }
127 
128 static long clk_pllv3_round_rate(struct clk_hw *hw, unsigned long rate,
129 				 unsigned long *prate)
130 {
131 	unsigned long parent_rate = *prate;
132 
133 	return (rate >= parent_rate * 22) ? parent_rate * 22 :
134 					    parent_rate * 20;
135 }
136 
137 static int clk_pllv3_set_rate(struct clk_hw *hw, unsigned long rate,
138 		unsigned long parent_rate)
139 {
140 	struct clk_pllv3 *pll = to_clk_pllv3(hw);
141 	u32 val, div;
142 
143 	if (rate == parent_rate * 22)
144 		div = 1;
145 	else if (rate == parent_rate * 20)
146 		div = 0;
147 	else
148 		return -EINVAL;
149 
150 	val = readl_relaxed(pll->base);
151 	val &= ~(pll->div_mask << pll->div_shift);
152 	val |= (div << pll->div_shift);
153 	writel_relaxed(val, pll->base);
154 
155 	return clk_pllv3_wait_lock(pll);
156 }
157 
158 static const struct clk_ops clk_pllv3_ops = {
159 	.prepare	= clk_pllv3_prepare,
160 	.unprepare	= clk_pllv3_unprepare,
161 	.is_prepared	= clk_pllv3_is_prepared,
162 	.recalc_rate	= clk_pllv3_recalc_rate,
163 	.round_rate	= clk_pllv3_round_rate,
164 	.set_rate	= clk_pllv3_set_rate,
165 };
166 
167 static unsigned long clk_pllv3_sys_recalc_rate(struct clk_hw *hw,
168 					       unsigned long parent_rate)
169 {
170 	struct clk_pllv3 *pll = to_clk_pllv3(hw);
171 	u32 div = readl_relaxed(pll->base) & pll->div_mask;
172 
173 	return parent_rate * div / 2;
174 }
175 
176 static long clk_pllv3_sys_round_rate(struct clk_hw *hw, unsigned long rate,
177 				     unsigned long *prate)
178 {
179 	unsigned long parent_rate = *prate;
180 	unsigned long min_rate = parent_rate * 54 / 2;
181 	unsigned long max_rate = parent_rate * 108 / 2;
182 	u32 div;
183 
184 	if (rate > max_rate)
185 		rate = max_rate;
186 	else if (rate < min_rate)
187 		rate = min_rate;
188 	div = rate * 2 / parent_rate;
189 
190 	return parent_rate * div / 2;
191 }
192 
193 static int clk_pllv3_sys_set_rate(struct clk_hw *hw, unsigned long rate,
194 		unsigned long parent_rate)
195 {
196 	struct clk_pllv3 *pll = to_clk_pllv3(hw);
197 	unsigned long min_rate = parent_rate * 54 / 2;
198 	unsigned long max_rate = parent_rate * 108 / 2;
199 	u32 val, div;
200 
201 	if (rate < min_rate || rate > max_rate)
202 		return -EINVAL;
203 
204 	div = rate * 2 / parent_rate;
205 	val = readl_relaxed(pll->base);
206 	val &= ~pll->div_mask;
207 	val |= div;
208 	writel_relaxed(val, pll->base);
209 
210 	return clk_pllv3_wait_lock(pll);
211 }
212 
213 static const struct clk_ops clk_pllv3_sys_ops = {
214 	.prepare	= clk_pllv3_prepare,
215 	.unprepare	= clk_pllv3_unprepare,
216 	.is_prepared	= clk_pllv3_is_prepared,
217 	.recalc_rate	= clk_pllv3_sys_recalc_rate,
218 	.round_rate	= clk_pllv3_sys_round_rate,
219 	.set_rate	= clk_pllv3_sys_set_rate,
220 };
221 
222 static unsigned long clk_pllv3_av_recalc_rate(struct clk_hw *hw,
223 					      unsigned long parent_rate)
224 {
225 	struct clk_pllv3 *pll = to_clk_pllv3(hw);
226 	u32 mfn = readl_relaxed(pll->base + pll->num_offset);
227 	u32 mfd = readl_relaxed(pll->base + pll->denom_offset);
228 	u32 div = readl_relaxed(pll->base) & pll->div_mask;
229 	u64 temp64 = (u64)parent_rate;
230 
231 	temp64 *= mfn;
232 	do_div(temp64, mfd);
233 
234 	return parent_rate * div + (unsigned long)temp64;
235 }
236 
237 static long clk_pllv3_av_round_rate(struct clk_hw *hw, unsigned long rate,
238 				    unsigned long *prate)
239 {
240 	unsigned long parent_rate = *prate;
241 	unsigned long min_rate = parent_rate * 27;
242 	unsigned long max_rate = parent_rate * 54;
243 	u32 div;
244 	u32 mfn, mfd = 1000000;
245 	u32 max_mfd = 0x3FFFFFFF;
246 	u64 temp64;
247 
248 	if (rate > max_rate)
249 		rate = max_rate;
250 	else if (rate < min_rate)
251 		rate = min_rate;
252 
253 	if (parent_rate <= max_mfd)
254 		mfd = parent_rate;
255 
256 	div = rate / parent_rate;
257 	temp64 = (u64) (rate - div * parent_rate);
258 	temp64 *= mfd;
259 	do_div(temp64, parent_rate);
260 	mfn = temp64;
261 
262 	temp64 = (u64)parent_rate;
263 	temp64 *= mfn;
264 	do_div(temp64, mfd);
265 
266 	return parent_rate * div + (unsigned long)temp64;
267 }
268 
269 static int clk_pllv3_av_set_rate(struct clk_hw *hw, unsigned long rate,
270 		unsigned long parent_rate)
271 {
272 	struct clk_pllv3 *pll = to_clk_pllv3(hw);
273 	unsigned long min_rate = parent_rate * 27;
274 	unsigned long max_rate = parent_rate * 54;
275 	u32 val, div;
276 	u32 mfn, mfd = 1000000;
277 	u32 max_mfd = 0x3FFFFFFF;
278 	u64 temp64;
279 
280 	if (rate < min_rate || rate > max_rate)
281 		return -EINVAL;
282 
283 	if (parent_rate <= max_mfd)
284 		mfd = parent_rate;
285 
286 	div = rate / parent_rate;
287 	temp64 = (u64) (rate - div * parent_rate);
288 	temp64 *= mfd;
289 	do_div(temp64, parent_rate);
290 	mfn = temp64;
291 
292 	val = readl_relaxed(pll->base);
293 	val &= ~pll->div_mask;
294 	val |= div;
295 	writel_relaxed(val, pll->base);
296 	writel_relaxed(mfn, pll->base + pll->num_offset);
297 	writel_relaxed(mfd, pll->base + pll->denom_offset);
298 
299 	return clk_pllv3_wait_lock(pll);
300 }
301 
302 static const struct clk_ops clk_pllv3_av_ops = {
303 	.prepare	= clk_pllv3_prepare,
304 	.unprepare	= clk_pllv3_unprepare,
305 	.is_prepared	= clk_pllv3_is_prepared,
306 	.recalc_rate	= clk_pllv3_av_recalc_rate,
307 	.round_rate	= clk_pllv3_av_round_rate,
308 	.set_rate	= clk_pllv3_av_set_rate,
309 };
310 
311 struct clk_pllv3_vf610_mf {
312 	u32 mfi;	/* integer part, can be 20 or 22 */
313 	u32 mfn;	/* numerator, 30-bit value */
314 	u32 mfd;	/* denominator, 30-bit value, must be less than mfn */
315 };
316 
317 static unsigned long clk_pllv3_vf610_mf_to_rate(unsigned long parent_rate,
318 		struct clk_pllv3_vf610_mf mf)
319 {
320 	u64 temp64;
321 
322 	temp64 = parent_rate;
323 	temp64 *= mf.mfn;
324 	do_div(temp64, mf.mfd);
325 
326 	return (parent_rate * mf.mfi) + temp64;
327 }
328 
329 static struct clk_pllv3_vf610_mf clk_pllv3_vf610_rate_to_mf(
330 		unsigned long parent_rate, unsigned long rate)
331 {
332 	struct clk_pllv3_vf610_mf mf;
333 	u64 temp64;
334 
335 	mf.mfi = (rate >= 22 * parent_rate) ? 22 : 20;
336 	mf.mfd = 0x3fffffff;	/* use max supported value for best accuracy */
337 
338 	if (rate <= parent_rate * mf.mfi)
339 		mf.mfn = 0;
340 	else if (rate >= parent_rate * (mf.mfi + 1))
341 		mf.mfn = mf.mfd - 1;
342 	else {
343 		/* rate = parent_rate * (mfi + mfn/mfd) */
344 		temp64 = rate - parent_rate * mf.mfi;
345 		temp64 *= mf.mfd;
346 		do_div(temp64, parent_rate);
347 		mf.mfn = temp64;
348 	}
349 
350 	return mf;
351 }
352 
353 static unsigned long clk_pllv3_vf610_recalc_rate(struct clk_hw *hw,
354 					      unsigned long parent_rate)
355 {
356 	struct clk_pllv3 *pll = to_clk_pllv3(hw);
357 	struct clk_pllv3_vf610_mf mf;
358 
359 	mf.mfn = readl_relaxed(pll->base + pll->num_offset);
360 	mf.mfd = readl_relaxed(pll->base + pll->denom_offset);
361 	mf.mfi = (readl_relaxed(pll->base) & pll->div_mask) ? 22 : 20;
362 
363 	return clk_pllv3_vf610_mf_to_rate(parent_rate, mf);
364 }
365 
366 static long clk_pllv3_vf610_round_rate(struct clk_hw *hw, unsigned long rate,
367 				    unsigned long *prate)
368 {
369 	struct clk_pllv3_vf610_mf mf = clk_pllv3_vf610_rate_to_mf(*prate, rate);
370 
371 	return clk_pllv3_vf610_mf_to_rate(*prate, mf);
372 }
373 
374 static int clk_pllv3_vf610_set_rate(struct clk_hw *hw, unsigned long rate,
375 		unsigned long parent_rate)
376 {
377 	struct clk_pllv3 *pll = to_clk_pllv3(hw);
378 	struct clk_pllv3_vf610_mf mf =
379 			clk_pllv3_vf610_rate_to_mf(parent_rate, rate);
380 	u32 val;
381 
382 	val = readl_relaxed(pll->base);
383 	if (mf.mfi == 20)
384 		val &= ~pll->div_mask;	/* clear bit for mfi=20 */
385 	else
386 		val |= pll->div_mask;	/* set bit for mfi=22 */
387 	writel_relaxed(val, pll->base);
388 
389 	writel_relaxed(mf.mfn, pll->base + pll->num_offset);
390 	writel_relaxed(mf.mfd, pll->base + pll->denom_offset);
391 
392 	return clk_pllv3_wait_lock(pll);
393 }
394 
395 static const struct clk_ops clk_pllv3_vf610_ops = {
396 	.prepare	= clk_pllv3_prepare,
397 	.unprepare	= clk_pllv3_unprepare,
398 	.is_prepared	= clk_pllv3_is_prepared,
399 	.recalc_rate	= clk_pllv3_vf610_recalc_rate,
400 	.round_rate	= clk_pllv3_vf610_round_rate,
401 	.set_rate	= clk_pllv3_vf610_set_rate,
402 };
403 
404 static unsigned long clk_pllv3_enet_recalc_rate(struct clk_hw *hw,
405 						unsigned long parent_rate)
406 {
407 	struct clk_pllv3 *pll = to_clk_pllv3(hw);
408 
409 	return pll->ref_clock;
410 }
411 
412 static const struct clk_ops clk_pllv3_enet_ops = {
413 	.prepare	= clk_pllv3_prepare,
414 	.unprepare	= clk_pllv3_unprepare,
415 	.is_prepared	= clk_pllv3_is_prepared,
416 	.recalc_rate	= clk_pllv3_enet_recalc_rate,
417 };
418 
419 struct clk *imx_clk_pllv3(enum imx_pllv3_type type, const char *name,
420 			  const char *parent_name, void __iomem *base,
421 			  u32 div_mask)
422 {
423 	struct clk_pllv3 *pll;
424 	const struct clk_ops *ops;
425 	struct clk *clk;
426 	struct clk_init_data init;
427 
428 	pll = kzalloc(sizeof(*pll), GFP_KERNEL);
429 	if (!pll)
430 		return ERR_PTR(-ENOMEM);
431 
432 	pll->power_bit = BM_PLL_POWER;
433 	pll->num_offset = PLL_NUM_OFFSET;
434 	pll->denom_offset = PLL_DENOM_OFFSET;
435 
436 	switch (type) {
437 	case IMX_PLLV3_SYS:
438 		ops = &clk_pllv3_sys_ops;
439 		break;
440 	case IMX_PLLV3_SYS_VF610:
441 		ops = &clk_pllv3_vf610_ops;
442 		pll->num_offset = PLL_VF610_NUM_OFFSET;
443 		pll->denom_offset = PLL_VF610_DENOM_OFFSET;
444 		break;
445 	case IMX_PLLV3_USB_VF610:
446 		pll->div_shift = 1;
447 		/* fall through */
448 	case IMX_PLLV3_USB:
449 		ops = &clk_pllv3_ops;
450 		pll->powerup_set = true;
451 		break;
452 	case IMX_PLLV3_AV_IMX7:
453 		pll->num_offset = PLL_IMX7_NUM_OFFSET;
454 		pll->denom_offset = PLL_IMX7_DENOM_OFFSET;
455 		/* fall through */
456 	case IMX_PLLV3_AV:
457 		ops = &clk_pllv3_av_ops;
458 		break;
459 	case IMX_PLLV3_ENET_IMX7:
460 		pll->power_bit = IMX7_ENET_PLL_POWER;
461 		pll->ref_clock = 1000000000;
462 		ops = &clk_pllv3_enet_ops;
463 		break;
464 	case IMX_PLLV3_ENET:
465 		pll->ref_clock = 500000000;
466 		ops = &clk_pllv3_enet_ops;
467 		break;
468 	case IMX_PLLV3_DDR_IMX7:
469 		pll->power_bit = IMX7_DDR_PLL_POWER;
470 		pll->num_offset = PLL_IMX7_NUM_OFFSET;
471 		pll->denom_offset = PLL_IMX7_DENOM_OFFSET;
472 		ops = &clk_pllv3_av_ops;
473 		break;
474 	default:
475 		ops = &clk_pllv3_ops;
476 	}
477 	pll->base = base;
478 	pll->div_mask = div_mask;
479 
480 	init.name = name;
481 	init.ops = ops;
482 	init.flags = 0;
483 	init.parent_names = &parent_name;
484 	init.num_parents = 1;
485 
486 	pll->hw.init = &init;
487 
488 	clk = clk_register(NULL, &pll->hw);
489 	if (IS_ERR(clk))
490 		kfree(pll);
491 
492 	return clk;
493 }
494