xref: /openbmc/linux/drivers/clk/x86/clk-cgu.c (revision 55b37d9c)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Copyright (C) 2020-2022 MaxLinear, Inc.
4  * Copyright (C) 2020 Intel Corporation.
5  * Zhu Yixin <yzhu@maxlinear.com>
6  * Rahul Tanwar <rtanwar@maxlinear.com>
7  */
8 #include <linux/clk-provider.h>
9 #include <linux/device.h>
10 #include <linux/of.h>
11 
12 #include "clk-cgu.h"
13 
14 #define GATE_HW_REG_STAT(reg)	((reg) + 0x0)
15 #define GATE_HW_REG_EN(reg)	((reg) + 0x4)
16 #define GATE_HW_REG_DIS(reg)	((reg) + 0x8)
17 #define MAX_DDIV_REG	8
18 #define MAX_DIVIDER_VAL 64
19 
20 #define to_lgm_clk_mux(_hw) container_of(_hw, struct lgm_clk_mux, hw)
21 #define to_lgm_clk_divider(_hw) container_of(_hw, struct lgm_clk_divider, hw)
22 #define to_lgm_clk_gate(_hw) container_of(_hw, struct lgm_clk_gate, hw)
23 #define to_lgm_clk_ddiv(_hw) container_of(_hw, struct lgm_clk_ddiv, hw)
24 
25 static struct clk_hw *lgm_clk_register_fixed(struct lgm_clk_provider *ctx,
26 					     const struct lgm_clk_branch *list)
27 {
28 
29 	if (list->div_flags & CLOCK_FLAG_VAL_INIT)
30 		lgm_set_clk_val(ctx->membase, list->div_off, list->div_shift,
31 				list->div_width, list->div_val);
32 
33 	return clk_hw_register_fixed_rate(NULL, list->name,
34 					  list->parent_data[0].name,
35 					  list->flags, list->mux_flags);
36 }
37 
38 static u8 lgm_clk_mux_get_parent(struct clk_hw *hw)
39 {
40 	struct lgm_clk_mux *mux = to_lgm_clk_mux(hw);
41 	u32 val;
42 
43 	if (mux->flags & MUX_CLK_SW)
44 		val = mux->reg;
45 	else
46 		val = lgm_get_clk_val(mux->membase, mux->reg, mux->shift,
47 				      mux->width);
48 	return clk_mux_val_to_index(hw, NULL, mux->flags, val);
49 }
50 
51 static int lgm_clk_mux_set_parent(struct clk_hw *hw, u8 index)
52 {
53 	struct lgm_clk_mux *mux = to_lgm_clk_mux(hw);
54 	u32 val;
55 
56 	val = clk_mux_index_to_val(NULL, mux->flags, index);
57 	if (mux->flags & MUX_CLK_SW)
58 		mux->reg = val;
59 	else
60 		lgm_set_clk_val(mux->membase, mux->reg, mux->shift,
61 				mux->width, val);
62 
63 	return 0;
64 }
65 
66 static int lgm_clk_mux_determine_rate(struct clk_hw *hw,
67 				      struct clk_rate_request *req)
68 {
69 	struct lgm_clk_mux *mux = to_lgm_clk_mux(hw);
70 
71 	return clk_mux_determine_rate_flags(hw, req, mux->flags);
72 }
73 
74 static const struct clk_ops lgm_clk_mux_ops = {
75 	.get_parent = lgm_clk_mux_get_parent,
76 	.set_parent = lgm_clk_mux_set_parent,
77 	.determine_rate = lgm_clk_mux_determine_rate,
78 };
79 
80 static struct clk_hw *
81 lgm_clk_register_mux(struct lgm_clk_provider *ctx,
82 		     const struct lgm_clk_branch *list)
83 {
84 	unsigned long cflags = list->mux_flags;
85 	struct device *dev = ctx->dev;
86 	u8 shift = list->mux_shift;
87 	u8 width = list->mux_width;
88 	struct clk_init_data init = {};
89 	struct lgm_clk_mux *mux;
90 	u32 reg = list->mux_off;
91 	struct clk_hw *hw;
92 	int ret;
93 
94 	mux = devm_kzalloc(dev, sizeof(*mux), GFP_KERNEL);
95 	if (!mux)
96 		return ERR_PTR(-ENOMEM);
97 
98 	init.name = list->name;
99 	init.ops = &lgm_clk_mux_ops;
100 	init.flags = list->flags;
101 	init.parent_data = list->parent_data;
102 	init.num_parents = list->num_parents;
103 
104 	mux->membase = ctx->membase;
105 	mux->reg = reg;
106 	mux->shift = shift;
107 	mux->width = width;
108 	mux->flags = cflags;
109 	mux->hw.init = &init;
110 
111 	hw = &mux->hw;
112 	ret = devm_clk_hw_register(dev, hw);
113 	if (ret)
114 		return ERR_PTR(ret);
115 
116 	if (cflags & CLOCK_FLAG_VAL_INIT)
117 		lgm_set_clk_val(mux->membase, reg, shift, width, list->mux_val);
118 
119 	return hw;
120 }
121 
122 static unsigned long
123 lgm_clk_divider_recalc_rate(struct clk_hw *hw, unsigned long parent_rate)
124 {
125 	struct lgm_clk_divider *divider = to_lgm_clk_divider(hw);
126 	unsigned int val;
127 
128 	val = lgm_get_clk_val(divider->membase, divider->reg,
129 			      divider->shift, divider->width);
130 
131 	return divider_recalc_rate(hw, parent_rate, val, divider->table,
132 				   divider->flags, divider->width);
133 }
134 
135 static long
136 lgm_clk_divider_round_rate(struct clk_hw *hw, unsigned long rate,
137 			   unsigned long *prate)
138 {
139 	struct lgm_clk_divider *divider = to_lgm_clk_divider(hw);
140 
141 	return divider_round_rate(hw, rate, prate, divider->table,
142 				  divider->width, divider->flags);
143 }
144 
145 static int
146 lgm_clk_divider_set_rate(struct clk_hw *hw, unsigned long rate,
147 			 unsigned long prate)
148 {
149 	struct lgm_clk_divider *divider = to_lgm_clk_divider(hw);
150 	int value;
151 
152 	value = divider_get_val(rate, prate, divider->table,
153 				divider->width, divider->flags);
154 	if (value < 0)
155 		return value;
156 
157 	lgm_set_clk_val(divider->membase, divider->reg,
158 			divider->shift, divider->width, value);
159 
160 	return 0;
161 }
162 
163 static int lgm_clk_divider_enable_disable(struct clk_hw *hw, int enable)
164 {
165 	struct lgm_clk_divider *div = to_lgm_clk_divider(hw);
166 
167 	if (div->flags != DIV_CLK_NO_MASK)
168 		lgm_set_clk_val(div->membase, div->reg, div->shift_gate,
169 				div->width_gate, enable);
170 	return 0;
171 }
172 
173 static int lgm_clk_divider_enable(struct clk_hw *hw)
174 {
175 	return lgm_clk_divider_enable_disable(hw, 1);
176 }
177 
178 static void lgm_clk_divider_disable(struct clk_hw *hw)
179 {
180 	lgm_clk_divider_enable_disable(hw, 0);
181 }
182 
183 static const struct clk_ops lgm_clk_divider_ops = {
184 	.recalc_rate = lgm_clk_divider_recalc_rate,
185 	.round_rate = lgm_clk_divider_round_rate,
186 	.set_rate = lgm_clk_divider_set_rate,
187 	.enable = lgm_clk_divider_enable,
188 	.disable = lgm_clk_divider_disable,
189 };
190 
191 static struct clk_hw *
192 lgm_clk_register_divider(struct lgm_clk_provider *ctx,
193 			 const struct lgm_clk_branch *list)
194 {
195 	unsigned long cflags = list->div_flags;
196 	struct device *dev = ctx->dev;
197 	struct lgm_clk_divider *div;
198 	struct clk_init_data init = {};
199 	u8 shift = list->div_shift;
200 	u8 width = list->div_width;
201 	u8 shift_gate = list->div_shift_gate;
202 	u8 width_gate = list->div_width_gate;
203 	u32 reg = list->div_off;
204 	struct clk_hw *hw;
205 	int ret;
206 
207 	div = devm_kzalloc(dev, sizeof(*div), GFP_KERNEL);
208 	if (!div)
209 		return ERR_PTR(-ENOMEM);
210 
211 	init.name = list->name;
212 	init.ops = &lgm_clk_divider_ops;
213 	init.flags = list->flags;
214 	init.parent_data = list->parent_data;
215 	init.num_parents = 1;
216 
217 	div->membase = ctx->membase;
218 	div->reg = reg;
219 	div->shift = shift;
220 	div->width = width;
221 	div->shift_gate	= shift_gate;
222 	div->width_gate	= width_gate;
223 	div->flags = cflags;
224 	div->table = list->div_table;
225 	div->hw.init = &init;
226 
227 	hw = &div->hw;
228 	ret = devm_clk_hw_register(dev, hw);
229 	if (ret)
230 		return ERR_PTR(ret);
231 
232 	if (cflags & CLOCK_FLAG_VAL_INIT)
233 		lgm_set_clk_val(div->membase, reg, shift, width, list->div_val);
234 
235 	return hw;
236 }
237 
238 static struct clk_hw *
239 lgm_clk_register_fixed_factor(struct lgm_clk_provider *ctx,
240 			      const struct lgm_clk_branch *list)
241 {
242 	struct clk_hw *hw;
243 
244 	hw = clk_hw_register_fixed_factor(ctx->dev, list->name,
245 					  list->parent_data[0].name, list->flags,
246 					  list->mult, list->div);
247 	if (IS_ERR(hw))
248 		return ERR_CAST(hw);
249 
250 	if (list->div_flags & CLOCK_FLAG_VAL_INIT)
251 		lgm_set_clk_val(ctx->membase, list->div_off, list->div_shift,
252 				list->div_width, list->div_val);
253 
254 	return hw;
255 }
256 
257 static int lgm_clk_gate_enable(struct clk_hw *hw)
258 {
259 	struct lgm_clk_gate *gate = to_lgm_clk_gate(hw);
260 	unsigned int reg;
261 
262 	reg = GATE_HW_REG_EN(gate->reg);
263 	lgm_set_clk_val(gate->membase, reg, gate->shift, 1, 1);
264 
265 	return 0;
266 }
267 
268 static void lgm_clk_gate_disable(struct clk_hw *hw)
269 {
270 	struct lgm_clk_gate *gate = to_lgm_clk_gate(hw);
271 	unsigned int reg;
272 
273 	reg = GATE_HW_REG_DIS(gate->reg);
274 	lgm_set_clk_val(gate->membase, reg, gate->shift, 1, 1);
275 }
276 
277 static int lgm_clk_gate_is_enabled(struct clk_hw *hw)
278 {
279 	struct lgm_clk_gate *gate = to_lgm_clk_gate(hw);
280 	unsigned int reg, ret;
281 
282 	reg = GATE_HW_REG_STAT(gate->reg);
283 	ret = lgm_get_clk_val(gate->membase, reg, gate->shift, 1);
284 
285 	return ret;
286 }
287 
288 static const struct clk_ops lgm_clk_gate_ops = {
289 	.enable = lgm_clk_gate_enable,
290 	.disable = lgm_clk_gate_disable,
291 	.is_enabled = lgm_clk_gate_is_enabled,
292 };
293 
294 static struct clk_hw *
295 lgm_clk_register_gate(struct lgm_clk_provider *ctx,
296 		      const struct lgm_clk_branch *list)
297 {
298 	unsigned long cflags = list->gate_flags;
299 	const char *pname = list->parent_data[0].name;
300 	struct device *dev = ctx->dev;
301 	u8 shift = list->gate_shift;
302 	struct clk_init_data init = {};
303 	struct lgm_clk_gate *gate;
304 	u32 reg = list->gate_off;
305 	struct clk_hw *hw;
306 	int ret;
307 
308 	gate = devm_kzalloc(dev, sizeof(*gate), GFP_KERNEL);
309 	if (!gate)
310 		return ERR_PTR(-ENOMEM);
311 
312 	init.name = list->name;
313 	init.ops = &lgm_clk_gate_ops;
314 	init.flags = list->flags;
315 	init.parent_names = pname ? &pname : NULL;
316 	init.num_parents = pname ? 1 : 0;
317 
318 	gate->membase = ctx->membase;
319 	gate->reg = reg;
320 	gate->shift = shift;
321 	gate->flags = cflags;
322 	gate->hw.init = &init;
323 
324 	hw = &gate->hw;
325 	ret = devm_clk_hw_register(dev, hw);
326 	if (ret)
327 		return ERR_PTR(ret);
328 
329 	if (cflags & CLOCK_FLAG_VAL_INIT) {
330 		lgm_set_clk_val(gate->membase, reg, shift, 1, list->gate_val);
331 	}
332 
333 	return hw;
334 }
335 
336 int lgm_clk_register_branches(struct lgm_clk_provider *ctx,
337 			      const struct lgm_clk_branch *list,
338 			      unsigned int nr_clk)
339 {
340 	struct clk_hw *hw;
341 	unsigned int idx;
342 
343 	for (idx = 0; idx < nr_clk; idx++, list++) {
344 		switch (list->type) {
345 		case CLK_TYPE_FIXED:
346 			hw = lgm_clk_register_fixed(ctx, list);
347 			break;
348 		case CLK_TYPE_MUX:
349 			hw = lgm_clk_register_mux(ctx, list);
350 			break;
351 		case CLK_TYPE_DIVIDER:
352 			hw = lgm_clk_register_divider(ctx, list);
353 			break;
354 		case CLK_TYPE_FIXED_FACTOR:
355 			hw = lgm_clk_register_fixed_factor(ctx, list);
356 			break;
357 		case CLK_TYPE_GATE:
358 			if (list->gate_flags & GATE_CLK_HW) {
359 				hw = lgm_clk_register_gate(ctx, list);
360 			} else {
361 				/*
362 				 * GATE_CLKs can be controlled either from
363 				 * CGU clk driver i.e. this driver or directly
364 				 * from power management driver/daemon. It is
365 				 * dependent on the power policy/profile requirements
366 				 * of the end product. To override control of gate
367 				 * clks from this driver, provide NULL for this index
368 				 * of gate clk provider.
369 				 */
370 				hw = NULL;
371 			}
372 			break;
373 
374 		default:
375 			dev_err(ctx->dev, "invalid clk type\n");
376 			return -EINVAL;
377 		}
378 
379 		if (IS_ERR(hw)) {
380 			dev_err(ctx->dev,
381 				"register clk: %s, type: %u failed!\n",
382 				list->name, list->type);
383 			return -EIO;
384 		}
385 		ctx->clk_data.hws[list->id] = hw;
386 	}
387 
388 	return 0;
389 }
390 
391 static unsigned long
392 lgm_clk_ddiv_recalc_rate(struct clk_hw *hw, unsigned long parent_rate)
393 {
394 	struct lgm_clk_ddiv *ddiv = to_lgm_clk_ddiv(hw);
395 	unsigned int div0, div1, exdiv;
396 	u64 prate;
397 
398 	div0 = lgm_get_clk_val(ddiv->membase, ddiv->reg,
399 			       ddiv->shift0, ddiv->width0) + 1;
400 	div1 = lgm_get_clk_val(ddiv->membase, ddiv->reg,
401 			       ddiv->shift1, ddiv->width1) + 1;
402 	exdiv = lgm_get_clk_val(ddiv->membase, ddiv->reg,
403 				ddiv->shift2, ddiv->width2);
404 	prate = (u64)parent_rate;
405 	do_div(prate, div0);
406 	do_div(prate, div1);
407 
408 	if (exdiv) {
409 		do_div(prate, ddiv->div);
410 		prate *= ddiv->mult;
411 	}
412 
413 	return prate;
414 }
415 
416 static int lgm_clk_ddiv_enable(struct clk_hw *hw)
417 {
418 	struct lgm_clk_ddiv *ddiv = to_lgm_clk_ddiv(hw);
419 
420 	lgm_set_clk_val(ddiv->membase, ddiv->reg, ddiv->shift_gate,
421 			ddiv->width_gate, 1);
422 	return 0;
423 }
424 
425 static void lgm_clk_ddiv_disable(struct clk_hw *hw)
426 {
427 	struct lgm_clk_ddiv *ddiv = to_lgm_clk_ddiv(hw);
428 
429 	lgm_set_clk_val(ddiv->membase, ddiv->reg, ddiv->shift_gate,
430 			ddiv->width_gate, 0);
431 }
432 
433 static int
434 lgm_clk_get_ddiv_val(u32 div, u32 *ddiv1, u32 *ddiv2)
435 {
436 	u32 idx, temp;
437 
438 	*ddiv1 = 1;
439 	*ddiv2 = 1;
440 
441 	if (div > MAX_DIVIDER_VAL)
442 		div = MAX_DIVIDER_VAL;
443 
444 	if (div > 1) {
445 		for (idx = 2; idx <= MAX_DDIV_REG; idx++) {
446 			temp = DIV_ROUND_UP_ULL((u64)div, idx);
447 			if (div % idx == 0 && temp <= MAX_DDIV_REG)
448 				break;
449 		}
450 
451 		if (idx > MAX_DDIV_REG)
452 			return -EINVAL;
453 
454 		*ddiv1 = temp;
455 		*ddiv2 = idx;
456 	}
457 
458 	return 0;
459 }
460 
461 static int
462 lgm_clk_ddiv_set_rate(struct clk_hw *hw, unsigned long rate,
463 		      unsigned long prate)
464 {
465 	struct lgm_clk_ddiv *ddiv = to_lgm_clk_ddiv(hw);
466 	u32 div, ddiv1, ddiv2;
467 
468 	div = DIV_ROUND_CLOSEST_ULL((u64)prate, rate);
469 
470 	if (lgm_get_clk_val(ddiv->membase, ddiv->reg, ddiv->shift2, 1)) {
471 		div = DIV_ROUND_CLOSEST_ULL((u64)div, 5);
472 		div = div * 2;
473 	}
474 
475 	if (div <= 0)
476 		return -EINVAL;
477 
478 	if (lgm_clk_get_ddiv_val(div, &ddiv1, &ddiv2))
479 		return -EINVAL;
480 
481 	lgm_set_clk_val(ddiv->membase, ddiv->reg, ddiv->shift0, ddiv->width0,
482 			ddiv1 - 1);
483 
484 	lgm_set_clk_val(ddiv->membase, ddiv->reg,  ddiv->shift1, ddiv->width1,
485 			ddiv2 - 1);
486 
487 	return 0;
488 }
489 
490 static long
491 lgm_clk_ddiv_round_rate(struct clk_hw *hw, unsigned long rate,
492 			unsigned long *prate)
493 {
494 	struct lgm_clk_ddiv *ddiv = to_lgm_clk_ddiv(hw);
495 	u32 div, ddiv1, ddiv2;
496 	u64 rate64;
497 
498 	div = DIV_ROUND_CLOSEST_ULL((u64)*prate, rate);
499 
500 	/* if predivide bit is enabled, modify div by factor of 2.5 */
501 	if (lgm_get_clk_val(ddiv->membase, ddiv->reg, ddiv->shift2, 1)) {
502 		div = div * 2;
503 		div = DIV_ROUND_CLOSEST_ULL((u64)div, 5);
504 	}
505 
506 	if (div <= 0)
507 		return *prate;
508 
509 	if (lgm_clk_get_ddiv_val(div, &ddiv1, &ddiv2) != 0)
510 		if (lgm_clk_get_ddiv_val(div + 1, &ddiv1, &ddiv2) != 0)
511 			return -EINVAL;
512 
513 	rate64 = *prate;
514 	do_div(rate64, ddiv1);
515 	do_div(rate64, ddiv2);
516 
517 	/* if predivide bit is enabled, modify rounded rate by factor of 2.5 */
518 	if (lgm_get_clk_val(ddiv->membase, ddiv->reg, ddiv->shift2, 1)) {
519 		rate64 = rate64 * 2;
520 		rate64 = DIV_ROUND_CLOSEST_ULL(rate64, 5);
521 	}
522 
523 	return rate64;
524 }
525 
526 static const struct clk_ops lgm_clk_ddiv_ops = {
527 	.recalc_rate = lgm_clk_ddiv_recalc_rate,
528 	.enable	= lgm_clk_ddiv_enable,
529 	.disable = lgm_clk_ddiv_disable,
530 	.set_rate = lgm_clk_ddiv_set_rate,
531 	.round_rate = lgm_clk_ddiv_round_rate,
532 };
533 
534 int lgm_clk_register_ddiv(struct lgm_clk_provider *ctx,
535 			  const struct lgm_clk_ddiv_data *list,
536 			  unsigned int nr_clk)
537 {
538 	struct device *dev = ctx->dev;
539 	struct clk_hw *hw;
540 	unsigned int idx;
541 	int ret;
542 
543 	for (idx = 0; idx < nr_clk; idx++, list++) {
544 		struct clk_init_data init = {};
545 		struct lgm_clk_ddiv *ddiv;
546 
547 		ddiv = devm_kzalloc(dev, sizeof(*ddiv), GFP_KERNEL);
548 		if (!ddiv)
549 			return -ENOMEM;
550 
551 		init.name = list->name;
552 		init.ops = &lgm_clk_ddiv_ops;
553 		init.flags = list->flags;
554 		init.parent_data = list->parent_data;
555 		init.num_parents = 1;
556 
557 		ddiv->membase = ctx->membase;
558 		ddiv->reg = list->reg;
559 		ddiv->shift0 = list->shift0;
560 		ddiv->width0 = list->width0;
561 		ddiv->shift1 = list->shift1;
562 		ddiv->width1 = list->width1;
563 		ddiv->shift_gate = list->shift_gate;
564 		ddiv->width_gate = list->width_gate;
565 		ddiv->shift2 = list->ex_shift;
566 		ddiv->width2 = list->ex_width;
567 		ddiv->flags = list->div_flags;
568 		ddiv->mult = 2;
569 		ddiv->div = 5;
570 		ddiv->hw.init = &init;
571 
572 		hw = &ddiv->hw;
573 		ret = devm_clk_hw_register(dev, hw);
574 		if (ret) {
575 			dev_err(dev, "register clk: %s failed!\n", list->name);
576 			return ret;
577 		}
578 		ctx->clk_data.hws[list->id] = hw;
579 	}
580 
581 	return 0;
582 }
583