xref: /openbmc/linux/drivers/clk/imx/clk-pll14xx.c (revision 1d05334d)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Copyright 2017-2018 NXP.
4  */
5 
6 #include <linux/bitops.h>
7 #include <linux/clk-provider.h>
8 #include <linux/err.h>
9 #include <linux/io.h>
10 #include <linux/iopoll.h>
11 #include <linux/slab.h>
12 #include <linux/jiffies.h>
13 
14 #include "clk.h"
15 
16 #define GNRL_CTL	0x0
17 #define DIV_CTL		0x4
18 #define LOCK_STATUS	BIT(31)
19 #define LOCK_SEL_MASK	BIT(29)
20 #define CLKE_MASK	BIT(11)
21 #define RST_MASK	BIT(9)
22 #define BYPASS_MASK	BIT(4)
23 #define MDIV_SHIFT	12
24 #define MDIV_MASK	GENMASK(21, 12)
25 #define PDIV_SHIFT	4
26 #define PDIV_MASK	GENMASK(9, 4)
27 #define SDIV_SHIFT	0
28 #define SDIV_MASK	GENMASK(2, 0)
29 #define KDIV_SHIFT	0
30 #define KDIV_MASK	GENMASK(15, 0)
31 
32 #define LOCK_TIMEOUT_US		10000
33 
34 struct clk_pll14xx {
35 	struct clk_hw			hw;
36 	void __iomem			*base;
37 	enum imx_pll14xx_type		type;
38 	const struct imx_pll14xx_rate_table *rate_table;
39 	int rate_count;
40 };
41 
42 #define to_clk_pll14xx(_hw) container_of(_hw, struct clk_pll14xx, hw)
43 
44 static const struct imx_pll14xx_rate_table imx_pll1416x_tbl[] = {
45 	PLL_1416X_RATE(1800000000U, 225, 3, 0),
46 	PLL_1416X_RATE(1600000000U, 200, 3, 0),
47 	PLL_1416X_RATE(1500000000U, 375, 3, 1),
48 	PLL_1416X_RATE(1400000000U, 350, 3, 1),
49 	PLL_1416X_RATE(1200000000U, 300, 3, 1),
50 	PLL_1416X_RATE(1000000000U, 250, 3, 1),
51 	PLL_1416X_RATE(800000000U,  200, 3, 1),
52 	PLL_1416X_RATE(750000000U,  250, 2, 2),
53 	PLL_1416X_RATE(700000000U,  350, 3, 2),
54 	PLL_1416X_RATE(600000000U,  300, 3, 2),
55 };
56 
57 static const struct imx_pll14xx_rate_table imx_pll1443x_tbl[] = {
58 	PLL_1443X_RATE(1039500000U, 173, 2, 1, 16384),
59 	PLL_1443X_RATE(650000000U, 325, 3, 2, 0),
60 	PLL_1443X_RATE(594000000U, 198, 2, 2, 0),
61 	PLL_1443X_RATE(519750000U, 173, 2, 2, 16384),
62 	PLL_1443X_RATE(393216000U, 262, 2, 3, 9437),
63 	PLL_1443X_RATE(361267200U, 361, 3, 3, 17511),
64 };
65 
66 struct imx_pll14xx_clk imx_1443x_pll = {
67 	.type = PLL_1443X,
68 	.rate_table = imx_pll1443x_tbl,
69 	.rate_count = ARRAY_SIZE(imx_pll1443x_tbl),
70 };
71 
72 struct imx_pll14xx_clk imx_1443x_dram_pll = {
73 	.type = PLL_1443X,
74 	.rate_table = imx_pll1443x_tbl,
75 	.rate_count = ARRAY_SIZE(imx_pll1443x_tbl),
76 	.flags = CLK_GET_RATE_NOCACHE,
77 };
78 
79 struct imx_pll14xx_clk imx_1416x_pll = {
80 	.type = PLL_1416X,
81 	.rate_table = imx_pll1416x_tbl,
82 	.rate_count = ARRAY_SIZE(imx_pll1416x_tbl),
83 };
84 
85 static const struct imx_pll14xx_rate_table *imx_get_pll_settings(
86 		struct clk_pll14xx *pll, unsigned long rate)
87 {
88 	const struct imx_pll14xx_rate_table *rate_table = pll->rate_table;
89 	int i;
90 
91 	for (i = 0; i < pll->rate_count; i++)
92 		if (rate == rate_table[i].rate)
93 			return &rate_table[i];
94 
95 	return NULL;
96 }
97 
98 static long clk_pll14xx_round_rate(struct clk_hw *hw, unsigned long rate,
99 			unsigned long *prate)
100 {
101 	struct clk_pll14xx *pll = to_clk_pll14xx(hw);
102 	const struct imx_pll14xx_rate_table *rate_table = pll->rate_table;
103 	int i;
104 
105 	/* Assumming rate_table is in descending order */
106 	for (i = 0; i < pll->rate_count; i++)
107 		if (rate >= rate_table[i].rate)
108 			return rate_table[i].rate;
109 
110 	/* return minimum supported value */
111 	return rate_table[i - 1].rate;
112 }
113 
114 static unsigned long clk_pll1416x_recalc_rate(struct clk_hw *hw,
115 						  unsigned long parent_rate)
116 {
117 	struct clk_pll14xx *pll = to_clk_pll14xx(hw);
118 	u32 mdiv, pdiv, sdiv, pll_div;
119 	u64 fvco = parent_rate;
120 
121 	pll_div = readl_relaxed(pll->base + 4);
122 	mdiv = (pll_div & MDIV_MASK) >> MDIV_SHIFT;
123 	pdiv = (pll_div & PDIV_MASK) >> PDIV_SHIFT;
124 	sdiv = (pll_div & SDIV_MASK) >> SDIV_SHIFT;
125 
126 	fvco *= mdiv;
127 	do_div(fvco, pdiv << sdiv);
128 
129 	return fvco;
130 }
131 
132 static unsigned long clk_pll1443x_recalc_rate(struct clk_hw *hw,
133 						  unsigned long parent_rate)
134 {
135 	struct clk_pll14xx *pll = to_clk_pll14xx(hw);
136 	u32 mdiv, pdiv, sdiv, pll_div_ctl0, pll_div_ctl1;
137 	short int kdiv;
138 	u64 fvco = parent_rate;
139 
140 	pll_div_ctl0 = readl_relaxed(pll->base + 4);
141 	pll_div_ctl1 = readl_relaxed(pll->base + 8);
142 	mdiv = (pll_div_ctl0 & MDIV_MASK) >> MDIV_SHIFT;
143 	pdiv = (pll_div_ctl0 & PDIV_MASK) >> PDIV_SHIFT;
144 	sdiv = (pll_div_ctl0 & SDIV_MASK) >> SDIV_SHIFT;
145 	kdiv = pll_div_ctl1 & KDIV_MASK;
146 
147 	/* fvco = (m * 65536 + k) * Fin / (p * 65536) */
148 	fvco *= (mdiv * 65536 + kdiv);
149 	pdiv *= 65536;
150 
151 	do_div(fvco, pdiv << sdiv);
152 
153 	return fvco;
154 }
155 
156 static inline bool clk_pll14xx_mp_change(const struct imx_pll14xx_rate_table *rate,
157 					  u32 pll_div)
158 {
159 	u32 old_mdiv, old_pdiv;
160 
161 	old_mdiv = (pll_div & MDIV_MASK) >> MDIV_SHIFT;
162 	old_pdiv = (pll_div & PDIV_MASK) >> PDIV_SHIFT;
163 
164 	return rate->mdiv != old_mdiv || rate->pdiv != old_pdiv;
165 }
166 
167 static int clk_pll14xx_wait_lock(struct clk_pll14xx *pll)
168 {
169 	u32 val;
170 
171 	return readl_poll_timeout(pll->base, val, val & LOCK_STATUS, 0,
172 			LOCK_TIMEOUT_US);
173 }
174 
175 static int clk_pll1416x_set_rate(struct clk_hw *hw, unsigned long drate,
176 				 unsigned long prate)
177 {
178 	struct clk_pll14xx *pll = to_clk_pll14xx(hw);
179 	const struct imx_pll14xx_rate_table *rate;
180 	u32 tmp, div_val;
181 	int ret;
182 
183 	rate = imx_get_pll_settings(pll, drate);
184 	if (!rate) {
185 		pr_err("%s: Invalid rate : %lu for pll clk %s\n", __func__,
186 		       drate, clk_hw_get_name(hw));
187 		return -EINVAL;
188 	}
189 
190 	tmp = readl_relaxed(pll->base + 4);
191 
192 	if (!clk_pll14xx_mp_change(rate, tmp)) {
193 		tmp &= ~(SDIV_MASK) << SDIV_SHIFT;
194 		tmp |= rate->sdiv << SDIV_SHIFT;
195 		writel_relaxed(tmp, pll->base + 4);
196 
197 		return 0;
198 	}
199 
200 	/* Bypass clock and set lock to pll output lock */
201 	tmp = readl_relaxed(pll->base);
202 	tmp |= LOCK_SEL_MASK;
203 	writel_relaxed(tmp, pll->base);
204 
205 	/* Enable RST */
206 	tmp &= ~RST_MASK;
207 	writel_relaxed(tmp, pll->base);
208 
209 	/* Enable BYPASS */
210 	tmp |= BYPASS_MASK;
211 	writel(tmp, pll->base);
212 
213 	div_val = (rate->mdiv << MDIV_SHIFT) | (rate->pdiv << PDIV_SHIFT) |
214 		(rate->sdiv << SDIV_SHIFT);
215 	writel_relaxed(div_val, pll->base + 0x4);
216 
217 	/*
218 	 * According to SPEC, t3 - t2 need to be greater than
219 	 * 1us and 1/FREF, respectively.
220 	 * FREF is FIN / Prediv, the prediv is [1, 63], so choose
221 	 * 3us.
222 	 */
223 	udelay(3);
224 
225 	/* Disable RST */
226 	tmp |= RST_MASK;
227 	writel_relaxed(tmp, pll->base);
228 
229 	/* Wait Lock */
230 	ret = clk_pll14xx_wait_lock(pll);
231 	if (ret)
232 		return ret;
233 
234 	/* Bypass */
235 	tmp &= ~BYPASS_MASK;
236 	writel_relaxed(tmp, pll->base);
237 
238 	return 0;
239 }
240 
241 static int clk_pll1443x_set_rate(struct clk_hw *hw, unsigned long drate,
242 				 unsigned long prate)
243 {
244 	struct clk_pll14xx *pll = to_clk_pll14xx(hw);
245 	const struct imx_pll14xx_rate_table *rate;
246 	u32 tmp, div_val;
247 	int ret;
248 
249 	rate = imx_get_pll_settings(pll, drate);
250 	if (!rate) {
251 		pr_err("%s: Invalid rate : %lu for pll clk %s\n", __func__,
252 			drate, clk_hw_get_name(hw));
253 		return -EINVAL;
254 	}
255 
256 	tmp = readl_relaxed(pll->base + 4);
257 
258 	if (!clk_pll14xx_mp_change(rate, tmp)) {
259 		tmp &= ~(SDIV_MASK) << SDIV_SHIFT;
260 		tmp |= rate->sdiv << SDIV_SHIFT;
261 		writel_relaxed(tmp, pll->base + 4);
262 
263 		tmp = rate->kdiv << KDIV_SHIFT;
264 		writel_relaxed(tmp, pll->base + 8);
265 
266 		return 0;
267 	}
268 
269 	/* Enable RST */
270 	tmp = readl_relaxed(pll->base);
271 	tmp &= ~RST_MASK;
272 	writel_relaxed(tmp, pll->base);
273 
274 	/* Enable BYPASS */
275 	tmp |= BYPASS_MASK;
276 	writel_relaxed(tmp, pll->base);
277 
278 	div_val = (rate->mdiv << MDIV_SHIFT) | (rate->pdiv << PDIV_SHIFT) |
279 		(rate->sdiv << SDIV_SHIFT);
280 	writel_relaxed(div_val, pll->base + 0x4);
281 	writel_relaxed(rate->kdiv << KDIV_SHIFT, pll->base + 0x8);
282 
283 	/*
284 	 * According to SPEC, t3 - t2 need to be greater than
285 	 * 1us and 1/FREF, respectively.
286 	 * FREF is FIN / Prediv, the prediv is [1, 63], so choose
287 	 * 3us.
288 	 */
289 	udelay(3);
290 
291 	/* Disable RST */
292 	tmp |= RST_MASK;
293 	writel_relaxed(tmp, pll->base);
294 
295 	/* Wait Lock*/
296 	ret = clk_pll14xx_wait_lock(pll);
297 	if (ret)
298 		return ret;
299 
300 	/* Bypass */
301 	tmp &= ~BYPASS_MASK;
302 	writel_relaxed(tmp, pll->base);
303 
304 	return 0;
305 }
306 
307 static int clk_pll14xx_prepare(struct clk_hw *hw)
308 {
309 	struct clk_pll14xx *pll = to_clk_pll14xx(hw);
310 	u32 val;
311 	int ret;
312 
313 	/*
314 	 * RESETB = 1 from 0, PLL starts its normal
315 	 * operation after lock time
316 	 */
317 	val = readl_relaxed(pll->base + GNRL_CTL);
318 	if (val & RST_MASK)
319 		return 0;
320 	val |= BYPASS_MASK;
321 	writel_relaxed(val, pll->base + GNRL_CTL);
322 	val |= RST_MASK;
323 	writel_relaxed(val, pll->base + GNRL_CTL);
324 
325 	ret = clk_pll14xx_wait_lock(pll);
326 	if (ret)
327 		return ret;
328 
329 	val &= ~BYPASS_MASK;
330 	writel_relaxed(val, pll->base + GNRL_CTL);
331 
332 	return 0;
333 }
334 
335 static int clk_pll14xx_is_prepared(struct clk_hw *hw)
336 {
337 	struct clk_pll14xx *pll = to_clk_pll14xx(hw);
338 	u32 val;
339 
340 	val = readl_relaxed(pll->base + GNRL_CTL);
341 
342 	return (val & RST_MASK) ? 1 : 0;
343 }
344 
345 static void clk_pll14xx_unprepare(struct clk_hw *hw)
346 {
347 	struct clk_pll14xx *pll = to_clk_pll14xx(hw);
348 	u32 val;
349 
350 	/*
351 	 * Set RST to 0, power down mode is enabled and
352 	 * every digital block is reset
353 	 */
354 	val = readl_relaxed(pll->base + GNRL_CTL);
355 	val &= ~RST_MASK;
356 	writel_relaxed(val, pll->base + GNRL_CTL);
357 }
358 
359 static const struct clk_ops clk_pll1416x_ops = {
360 	.prepare	= clk_pll14xx_prepare,
361 	.unprepare	= clk_pll14xx_unprepare,
362 	.is_prepared	= clk_pll14xx_is_prepared,
363 	.recalc_rate	= clk_pll1416x_recalc_rate,
364 	.round_rate	= clk_pll14xx_round_rate,
365 	.set_rate	= clk_pll1416x_set_rate,
366 };
367 
368 static const struct clk_ops clk_pll1416x_min_ops = {
369 	.recalc_rate	= clk_pll1416x_recalc_rate,
370 };
371 
372 static const struct clk_ops clk_pll1443x_ops = {
373 	.prepare	= clk_pll14xx_prepare,
374 	.unprepare	= clk_pll14xx_unprepare,
375 	.is_prepared	= clk_pll14xx_is_prepared,
376 	.recalc_rate	= clk_pll1443x_recalc_rate,
377 	.round_rate	= clk_pll14xx_round_rate,
378 	.set_rate	= clk_pll1443x_set_rate,
379 };
380 
381 struct clk_hw *imx_clk_hw_pll14xx(const char *name, const char *parent_name,
382 				  void __iomem *base,
383 				  const struct imx_pll14xx_clk *pll_clk)
384 {
385 	struct clk_pll14xx *pll;
386 	struct clk_hw *hw;
387 	struct clk_init_data init;
388 	int ret;
389 	u32 val;
390 
391 	pll = kzalloc(sizeof(*pll), GFP_KERNEL);
392 	if (!pll)
393 		return ERR_PTR(-ENOMEM);
394 
395 	init.name = name;
396 	init.flags = pll_clk->flags;
397 	init.parent_names = &parent_name;
398 	init.num_parents = 1;
399 
400 	switch (pll_clk->type) {
401 	case PLL_1416X:
402 		if (!pll_clk->rate_table)
403 			init.ops = &clk_pll1416x_min_ops;
404 		else
405 			init.ops = &clk_pll1416x_ops;
406 		break;
407 	case PLL_1443X:
408 		init.ops = &clk_pll1443x_ops;
409 		break;
410 	default:
411 		pr_err("%s: Unknown pll type for pll clk %s\n",
412 		       __func__, name);
413 		kfree(pll);
414 		return ERR_PTR(-EINVAL);
415 	};
416 
417 	pll->base = base;
418 	pll->hw.init = &init;
419 	pll->type = pll_clk->type;
420 	pll->rate_table = pll_clk->rate_table;
421 	pll->rate_count = pll_clk->rate_count;
422 
423 	val = readl_relaxed(pll->base + GNRL_CTL);
424 	val &= ~BYPASS_MASK;
425 	writel_relaxed(val, pll->base + GNRL_CTL);
426 
427 	hw = &pll->hw;
428 
429 	ret = clk_hw_register(NULL, hw);
430 	if (ret) {
431 		pr_err("%s: failed to register pll %s %d\n",
432 			__func__, name, ret);
433 		kfree(pll);
434 		return ERR_PTR(ret);
435 	}
436 
437 	return hw;
438 }
439