xref: /linux/drivers/clk/x86/clk-cgu.c (revision 23c48a124b469cee2eb0c75e6d22d366d1caa118)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Copyright (C) 2020 Intel Corporation.
4  * Zhu YiXin <yixin.zhu@intel.com>
5  * Rahul Tanwar <rahul.tanwar@intel.com>
6  */
7 #include <linux/clk-provider.h>
8 #include <linux/device.h>
9 #include <linux/of.h>
10 
11 #include "clk-cgu.h"
12 
13 #define GATE_HW_REG_STAT(reg)	((reg) + 0x0)
14 #define GATE_HW_REG_EN(reg)	((reg) + 0x4)
15 #define GATE_HW_REG_DIS(reg)	((reg) + 0x8)
16 #define MAX_DDIV_REG	8
17 #define MAX_DIVIDER_VAL 64
18 
19 #define to_lgm_clk_mux(_hw) container_of(_hw, struct lgm_clk_mux, hw)
20 #define to_lgm_clk_divider(_hw) container_of(_hw, struct lgm_clk_divider, hw)
21 #define to_lgm_clk_gate(_hw) container_of(_hw, struct lgm_clk_gate, hw)
22 #define to_lgm_clk_ddiv(_hw) container_of(_hw, struct lgm_clk_ddiv, hw)
23 
24 static struct clk_hw *lgm_clk_register_fixed(struct lgm_clk_provider *ctx,
25 					     const struct lgm_clk_branch *list)
26 {
27 	unsigned long flags;
28 
29 	if (list->div_flags & CLOCK_FLAG_VAL_INIT) {
30 		spin_lock_irqsave(&ctx->lock, flags);
31 		lgm_set_clk_val(ctx->membase, list->div_off, list->div_shift,
32 				list->div_width, list->div_val);
33 		spin_unlock_irqrestore(&ctx->lock, flags);
34 	}
35 
36 	return clk_hw_register_fixed_rate(NULL, list->name,
37 					  list->parent_data[0].name,
38 					  list->flags, list->mux_flags);
39 }
40 
41 static u8 lgm_clk_mux_get_parent(struct clk_hw *hw)
42 {
43 	struct lgm_clk_mux *mux = to_lgm_clk_mux(hw);
44 	unsigned long flags;
45 	u32 val;
46 
47 	spin_lock_irqsave(&mux->lock, flags);
48 	if (mux->flags & MUX_CLK_SW)
49 		val = mux->reg;
50 	else
51 		val = lgm_get_clk_val(mux->membase, mux->reg, mux->shift,
52 				      mux->width);
53 	spin_unlock_irqrestore(&mux->lock, flags);
54 	return clk_mux_val_to_index(hw, NULL, mux->flags, val);
55 }
56 
57 static int lgm_clk_mux_set_parent(struct clk_hw *hw, u8 index)
58 {
59 	struct lgm_clk_mux *mux = to_lgm_clk_mux(hw);
60 	unsigned long flags;
61 	u32 val;
62 
63 	val = clk_mux_index_to_val(NULL, mux->flags, index);
64 	spin_lock_irqsave(&mux->lock, flags);
65 	if (mux->flags & MUX_CLK_SW)
66 		mux->reg = val;
67 	else
68 		lgm_set_clk_val(mux->membase, mux->reg, mux->shift,
69 				mux->width, val);
70 	spin_unlock_irqrestore(&mux->lock, flags);
71 
72 	return 0;
73 }
74 
75 static int lgm_clk_mux_determine_rate(struct clk_hw *hw,
76 				      struct clk_rate_request *req)
77 {
78 	struct lgm_clk_mux *mux = to_lgm_clk_mux(hw);
79 
80 	return clk_mux_determine_rate_flags(hw, req, mux->flags);
81 }
82 
83 static const struct clk_ops lgm_clk_mux_ops = {
84 	.get_parent = lgm_clk_mux_get_parent,
85 	.set_parent = lgm_clk_mux_set_parent,
86 	.determine_rate = lgm_clk_mux_determine_rate,
87 };
88 
89 static struct clk_hw *
90 lgm_clk_register_mux(struct lgm_clk_provider *ctx,
91 		     const struct lgm_clk_branch *list)
92 {
93 	unsigned long flags, cflags = list->mux_flags;
94 	struct device *dev = ctx->dev;
95 	u8 shift = list->mux_shift;
96 	u8 width = list->mux_width;
97 	struct clk_init_data init = {};
98 	struct lgm_clk_mux *mux;
99 	u32 reg = list->mux_off;
100 	struct clk_hw *hw;
101 	int ret;
102 
103 	mux = devm_kzalloc(dev, sizeof(*mux), GFP_KERNEL);
104 	if (!mux)
105 		return ERR_PTR(-ENOMEM);
106 
107 	init.name = list->name;
108 	init.ops = &lgm_clk_mux_ops;
109 	init.flags = list->flags;
110 	init.parent_data = list->parent_data;
111 	init.num_parents = list->num_parents;
112 
113 	mux->membase = ctx->membase;
114 	mux->lock = ctx->lock;
115 	mux->reg = reg;
116 	mux->shift = shift;
117 	mux->width = width;
118 	mux->flags = cflags;
119 	mux->hw.init = &init;
120 
121 	hw = &mux->hw;
122 	ret = devm_clk_hw_register(dev, hw);
123 	if (ret)
124 		return ERR_PTR(ret);
125 
126 	if (cflags & CLOCK_FLAG_VAL_INIT) {
127 		spin_lock_irqsave(&mux->lock, flags);
128 		lgm_set_clk_val(mux->membase, reg, shift, width, list->mux_val);
129 		spin_unlock_irqrestore(&mux->lock, flags);
130 	}
131 
132 	return hw;
133 }
134 
135 static unsigned long
136 lgm_clk_divider_recalc_rate(struct clk_hw *hw, unsigned long parent_rate)
137 {
138 	struct lgm_clk_divider *divider = to_lgm_clk_divider(hw);
139 	unsigned long flags;
140 	unsigned int val;
141 
142 	spin_lock_irqsave(&divider->lock, flags);
143 	val = lgm_get_clk_val(divider->membase, divider->reg,
144 			      divider->shift, divider->width);
145 	spin_unlock_irqrestore(&divider->lock, flags);
146 
147 	return divider_recalc_rate(hw, parent_rate, val, divider->table,
148 				   divider->flags, divider->width);
149 }
150 
151 static long
152 lgm_clk_divider_round_rate(struct clk_hw *hw, unsigned long rate,
153 			   unsigned long *prate)
154 {
155 	struct lgm_clk_divider *divider = to_lgm_clk_divider(hw);
156 
157 	return divider_round_rate(hw, rate, prate, divider->table,
158 				  divider->width, divider->flags);
159 }
160 
161 static int
162 lgm_clk_divider_set_rate(struct clk_hw *hw, unsigned long rate,
163 			 unsigned long prate)
164 {
165 	struct lgm_clk_divider *divider = to_lgm_clk_divider(hw);
166 	unsigned long flags;
167 	int value;
168 
169 	value = divider_get_val(rate, prate, divider->table,
170 				divider->width, divider->flags);
171 	if (value < 0)
172 		return value;
173 
174 	spin_lock_irqsave(&divider->lock, flags);
175 	lgm_set_clk_val(divider->membase, divider->reg,
176 			divider->shift, divider->width, value);
177 	spin_unlock_irqrestore(&divider->lock, flags);
178 
179 	return 0;
180 }
181 
182 static int lgm_clk_divider_enable_disable(struct clk_hw *hw, int enable)
183 {
184 	struct lgm_clk_divider *div = to_lgm_clk_divider(hw);
185 	unsigned long flags;
186 
187 	spin_lock_irqsave(&div->lock, flags);
188 	lgm_set_clk_val(div->membase, div->reg, div->shift_gate,
189 			div->width_gate, enable);
190 	spin_unlock_irqrestore(&div->lock, flags);
191 	return 0;
192 }
193 
194 static int lgm_clk_divider_enable(struct clk_hw *hw)
195 {
196 	return lgm_clk_divider_enable_disable(hw, 1);
197 }
198 
199 static void lgm_clk_divider_disable(struct clk_hw *hw)
200 {
201 	lgm_clk_divider_enable_disable(hw, 0);
202 }
203 
204 static const struct clk_ops lgm_clk_divider_ops = {
205 	.recalc_rate = lgm_clk_divider_recalc_rate,
206 	.round_rate = lgm_clk_divider_round_rate,
207 	.set_rate = lgm_clk_divider_set_rate,
208 	.enable = lgm_clk_divider_enable,
209 	.disable = lgm_clk_divider_disable,
210 };
211 
212 static struct clk_hw *
213 lgm_clk_register_divider(struct lgm_clk_provider *ctx,
214 			 const struct lgm_clk_branch *list)
215 {
216 	unsigned long flags, cflags = list->div_flags;
217 	struct device *dev = ctx->dev;
218 	struct lgm_clk_divider *div;
219 	struct clk_init_data init = {};
220 	u8 shift = list->div_shift;
221 	u8 width = list->div_width;
222 	u8 shift_gate = list->div_shift_gate;
223 	u8 width_gate = list->div_width_gate;
224 	u32 reg = list->div_off;
225 	struct clk_hw *hw;
226 	int ret;
227 
228 	div = devm_kzalloc(dev, sizeof(*div), GFP_KERNEL);
229 	if (!div)
230 		return ERR_PTR(-ENOMEM);
231 
232 	init.name = list->name;
233 	init.ops = &lgm_clk_divider_ops;
234 	init.flags = list->flags;
235 	init.parent_data = list->parent_data;
236 	init.num_parents = 1;
237 
238 	div->membase = ctx->membase;
239 	div->lock = ctx->lock;
240 	div->reg = reg;
241 	div->shift = shift;
242 	div->width = width;
243 	div->shift_gate	= shift_gate;
244 	div->width_gate	= width_gate;
245 	div->flags = cflags;
246 	div->table = list->div_table;
247 	div->hw.init = &init;
248 
249 	hw = &div->hw;
250 	ret = devm_clk_hw_register(dev, hw);
251 	if (ret)
252 		return ERR_PTR(ret);
253 
254 	if (cflags & CLOCK_FLAG_VAL_INIT) {
255 		spin_lock_irqsave(&div->lock, flags);
256 		lgm_set_clk_val(div->membase, reg, shift, width, list->div_val);
257 		spin_unlock_irqrestore(&div->lock, flags);
258 	}
259 
260 	return hw;
261 }
262 
263 static struct clk_hw *
264 lgm_clk_register_fixed_factor(struct lgm_clk_provider *ctx,
265 			      const struct lgm_clk_branch *list)
266 {
267 	unsigned long flags;
268 	struct clk_hw *hw;
269 
270 	hw = clk_hw_register_fixed_factor(ctx->dev, list->name,
271 					  list->parent_data[0].name, list->flags,
272 					  list->mult, list->div);
273 	if (IS_ERR(hw))
274 		return ERR_CAST(hw);
275 
276 	if (list->div_flags & CLOCK_FLAG_VAL_INIT) {
277 		spin_lock_irqsave(&ctx->lock, flags);
278 		lgm_set_clk_val(ctx->membase, list->div_off, list->div_shift,
279 				list->div_width, list->div_val);
280 		spin_unlock_irqrestore(&ctx->lock, flags);
281 	}
282 
283 	return hw;
284 }
285 
286 static int lgm_clk_gate_enable(struct clk_hw *hw)
287 {
288 	struct lgm_clk_gate *gate = to_lgm_clk_gate(hw);
289 	unsigned long flags;
290 	unsigned int reg;
291 
292 	spin_lock_irqsave(&gate->lock, flags);
293 	reg = GATE_HW_REG_EN(gate->reg);
294 	lgm_set_clk_val(gate->membase, reg, gate->shift, 1, 1);
295 	spin_unlock_irqrestore(&gate->lock, flags);
296 
297 	return 0;
298 }
299 
300 static void lgm_clk_gate_disable(struct clk_hw *hw)
301 {
302 	struct lgm_clk_gate *gate = to_lgm_clk_gate(hw);
303 	unsigned long flags;
304 	unsigned int reg;
305 
306 	spin_lock_irqsave(&gate->lock, flags);
307 	reg = GATE_HW_REG_DIS(gate->reg);
308 	lgm_set_clk_val(gate->membase, reg, gate->shift, 1, 1);
309 	spin_unlock_irqrestore(&gate->lock, flags);
310 }
311 
312 static int lgm_clk_gate_is_enabled(struct clk_hw *hw)
313 {
314 	struct lgm_clk_gate *gate = to_lgm_clk_gate(hw);
315 	unsigned int reg, ret;
316 	unsigned long flags;
317 
318 	spin_lock_irqsave(&gate->lock, flags);
319 	reg = GATE_HW_REG_STAT(gate->reg);
320 	ret = lgm_get_clk_val(gate->membase, reg, gate->shift, 1);
321 	spin_unlock_irqrestore(&gate->lock, flags);
322 
323 	return ret;
324 }
325 
326 static const struct clk_ops lgm_clk_gate_ops = {
327 	.enable = lgm_clk_gate_enable,
328 	.disable = lgm_clk_gate_disable,
329 	.is_enabled = lgm_clk_gate_is_enabled,
330 };
331 
332 static struct clk_hw *
333 lgm_clk_register_gate(struct lgm_clk_provider *ctx,
334 		      const struct lgm_clk_branch *list)
335 {
336 	unsigned long flags, cflags = list->gate_flags;
337 	const char *pname = list->parent_data[0].name;
338 	struct device *dev = ctx->dev;
339 	u8 shift = list->gate_shift;
340 	struct clk_init_data init = {};
341 	struct lgm_clk_gate *gate;
342 	u32 reg = list->gate_off;
343 	struct clk_hw *hw;
344 	int ret;
345 
346 	gate = devm_kzalloc(dev, sizeof(*gate), GFP_KERNEL);
347 	if (!gate)
348 		return ERR_PTR(-ENOMEM);
349 
350 	init.name = list->name;
351 	init.ops = &lgm_clk_gate_ops;
352 	init.flags = list->flags;
353 	init.parent_names = pname ? &pname : NULL;
354 	init.num_parents = pname ? 1 : 0;
355 
356 	gate->membase = ctx->membase;
357 	gate->lock = ctx->lock;
358 	gate->reg = reg;
359 	gate->shift = shift;
360 	gate->flags = cflags;
361 	gate->hw.init = &init;
362 
363 	hw = &gate->hw;
364 	ret = devm_clk_hw_register(dev, hw);
365 	if (ret)
366 		return ERR_PTR(ret);
367 
368 	if (cflags & CLOCK_FLAG_VAL_INIT) {
369 		spin_lock_irqsave(&gate->lock, flags);
370 		lgm_set_clk_val(gate->membase, reg, shift, 1, list->gate_val);
371 		spin_unlock_irqrestore(&gate->lock, flags);
372 	}
373 
374 	return hw;
375 }
376 
377 int lgm_clk_register_branches(struct lgm_clk_provider *ctx,
378 			      const struct lgm_clk_branch *list,
379 			      unsigned int nr_clk)
380 {
381 	struct clk_hw *hw;
382 	unsigned int idx;
383 
384 	for (idx = 0; idx < nr_clk; idx++, list++) {
385 		switch (list->type) {
386 		case CLK_TYPE_FIXED:
387 			hw = lgm_clk_register_fixed(ctx, list);
388 			break;
389 		case CLK_TYPE_MUX:
390 			hw = lgm_clk_register_mux(ctx, list);
391 			break;
392 		case CLK_TYPE_DIVIDER:
393 			hw = lgm_clk_register_divider(ctx, list);
394 			break;
395 		case CLK_TYPE_FIXED_FACTOR:
396 			hw = lgm_clk_register_fixed_factor(ctx, list);
397 			break;
398 		case CLK_TYPE_GATE:
399 			hw = lgm_clk_register_gate(ctx, list);
400 			break;
401 		default:
402 			dev_err(ctx->dev, "invalid clk type\n");
403 			return -EINVAL;
404 		}
405 
406 		if (IS_ERR(hw)) {
407 			dev_err(ctx->dev,
408 				"register clk: %s, type: %u failed!\n",
409 				list->name, list->type);
410 			return -EIO;
411 		}
412 		ctx->clk_data.hws[list->id] = hw;
413 	}
414 
415 	return 0;
416 }
417 
418 static unsigned long
419 lgm_clk_ddiv_recalc_rate(struct clk_hw *hw, unsigned long parent_rate)
420 {
421 	struct lgm_clk_ddiv *ddiv = to_lgm_clk_ddiv(hw);
422 	unsigned int div0, div1, exdiv;
423 	u64 prate;
424 
425 	div0 = lgm_get_clk_val(ddiv->membase, ddiv->reg,
426 			       ddiv->shift0, ddiv->width0) + 1;
427 	div1 = lgm_get_clk_val(ddiv->membase, ddiv->reg,
428 			       ddiv->shift1, ddiv->width1) + 1;
429 	exdiv = lgm_get_clk_val(ddiv->membase, ddiv->reg,
430 				ddiv->shift2, ddiv->width2);
431 	prate = (u64)parent_rate;
432 	do_div(prate, div0);
433 	do_div(prate, div1);
434 
435 	if (exdiv) {
436 		do_div(prate, ddiv->div);
437 		prate *= ddiv->mult;
438 	}
439 
440 	return prate;
441 }
442 
443 static int lgm_clk_ddiv_enable(struct clk_hw *hw)
444 {
445 	struct lgm_clk_ddiv *ddiv = to_lgm_clk_ddiv(hw);
446 	unsigned long flags;
447 
448 	spin_lock_irqsave(&ddiv->lock, flags);
449 	lgm_set_clk_val(ddiv->membase, ddiv->reg, ddiv->shift_gate,
450 			ddiv->width_gate, 1);
451 	spin_unlock_irqrestore(&ddiv->lock, flags);
452 	return 0;
453 }
454 
455 static void lgm_clk_ddiv_disable(struct clk_hw *hw)
456 {
457 	struct lgm_clk_ddiv *ddiv = to_lgm_clk_ddiv(hw);
458 	unsigned long flags;
459 
460 	spin_lock_irqsave(&ddiv->lock, flags);
461 	lgm_set_clk_val(ddiv->membase, ddiv->reg, ddiv->shift_gate,
462 			ddiv->width_gate, 0);
463 	spin_unlock_irqrestore(&ddiv->lock, flags);
464 }
465 
466 static int
467 lgm_clk_get_ddiv_val(u32 div, u32 *ddiv1, u32 *ddiv2)
468 {
469 	u32 idx, temp;
470 
471 	*ddiv1 = 1;
472 	*ddiv2 = 1;
473 
474 	if (div > MAX_DIVIDER_VAL)
475 		div = MAX_DIVIDER_VAL;
476 
477 	if (div > 1) {
478 		for (idx = 2; idx <= MAX_DDIV_REG; idx++) {
479 			temp = DIV_ROUND_UP_ULL((u64)div, idx);
480 			if (div % idx == 0 && temp <= MAX_DDIV_REG)
481 				break;
482 		}
483 
484 		if (idx > MAX_DDIV_REG)
485 			return -EINVAL;
486 
487 		*ddiv1 = temp;
488 		*ddiv2 = idx;
489 	}
490 
491 	return 0;
492 }
493 
494 static int
495 lgm_clk_ddiv_set_rate(struct clk_hw *hw, unsigned long rate,
496 		      unsigned long prate)
497 {
498 	struct lgm_clk_ddiv *ddiv = to_lgm_clk_ddiv(hw);
499 	u32 div, ddiv1, ddiv2;
500 	unsigned long flags;
501 
502 	div = DIV_ROUND_CLOSEST_ULL((u64)prate, rate);
503 
504 	spin_lock_irqsave(&ddiv->lock, flags);
505 	if (lgm_get_clk_val(ddiv->membase, ddiv->reg, ddiv->shift2, 1)) {
506 		div = DIV_ROUND_CLOSEST_ULL((u64)div, 5);
507 		div = div * 2;
508 	}
509 
510 	if (div <= 0) {
511 		spin_unlock_irqrestore(&ddiv->lock, flags);
512 		return -EINVAL;
513 	}
514 
515 	if (lgm_clk_get_ddiv_val(div, &ddiv1, &ddiv2)) {
516 		spin_unlock_irqrestore(&ddiv->lock, flags);
517 		return -EINVAL;
518 	}
519 
520 	lgm_set_clk_val(ddiv->membase, ddiv->reg, ddiv->shift0, ddiv->width0,
521 			ddiv1 - 1);
522 
523 	lgm_set_clk_val(ddiv->membase, ddiv->reg,  ddiv->shift1, ddiv->width1,
524 			ddiv2 - 1);
525 	spin_unlock_irqrestore(&ddiv->lock, flags);
526 
527 	return 0;
528 }
529 
530 static long
531 lgm_clk_ddiv_round_rate(struct clk_hw *hw, unsigned long rate,
532 			unsigned long *prate)
533 {
534 	struct lgm_clk_ddiv *ddiv = to_lgm_clk_ddiv(hw);
535 	u32 div, ddiv1, ddiv2;
536 	unsigned long flags;
537 	u64 rate64;
538 
539 	div = DIV_ROUND_CLOSEST_ULL((u64)*prate, rate);
540 
541 	/* if predivide bit is enabled, modify div by factor of 2.5 */
542 	spin_lock_irqsave(&ddiv->lock, flags);
543 	if (lgm_get_clk_val(ddiv->membase, ddiv->reg, ddiv->shift2, 1)) {
544 		div = div * 2;
545 		div = DIV_ROUND_CLOSEST_ULL((u64)div, 5);
546 	}
547 	spin_unlock_irqrestore(&ddiv->lock, flags);
548 
549 	if (div <= 0)
550 		return *prate;
551 
552 	if (lgm_clk_get_ddiv_val(div, &ddiv1, &ddiv2) != 0)
553 		if (lgm_clk_get_ddiv_val(div + 1, &ddiv1, &ddiv2) != 0)
554 			return -EINVAL;
555 
556 	rate64 = *prate;
557 	do_div(rate64, ddiv1);
558 	do_div(rate64, ddiv2);
559 
560 	/* if predivide bit is enabled, modify rounded rate by factor of 2.5 */
561 	spin_lock_irqsave(&ddiv->lock, flags);
562 	if (lgm_get_clk_val(ddiv->membase, ddiv->reg, ddiv->shift2, 1)) {
563 		rate64 = rate64 * 2;
564 		rate64 = DIV_ROUND_CLOSEST_ULL(rate64, 5);
565 	}
566 	spin_unlock_irqrestore(&ddiv->lock, flags);
567 
568 	return rate64;
569 }
570 
571 static const struct clk_ops lgm_clk_ddiv_ops = {
572 	.recalc_rate = lgm_clk_ddiv_recalc_rate,
573 	.enable	= lgm_clk_ddiv_enable,
574 	.disable = lgm_clk_ddiv_disable,
575 	.set_rate = lgm_clk_ddiv_set_rate,
576 	.round_rate = lgm_clk_ddiv_round_rate,
577 };
578 
579 int lgm_clk_register_ddiv(struct lgm_clk_provider *ctx,
580 			  const struct lgm_clk_ddiv_data *list,
581 			  unsigned int nr_clk)
582 {
583 	struct device *dev = ctx->dev;
584 	struct clk_hw *hw;
585 	unsigned int idx;
586 	int ret;
587 
588 	for (idx = 0; idx < nr_clk; idx++, list++) {
589 		struct clk_init_data init = {};
590 		struct lgm_clk_ddiv *ddiv;
591 
592 		ddiv = devm_kzalloc(dev, sizeof(*ddiv), GFP_KERNEL);
593 		if (!ddiv)
594 			return -ENOMEM;
595 
596 		init.name = list->name;
597 		init.ops = &lgm_clk_ddiv_ops;
598 		init.flags = list->flags;
599 		init.parent_data = list->parent_data;
600 		init.num_parents = 1;
601 
602 		ddiv->membase = ctx->membase;
603 		ddiv->lock = ctx->lock;
604 		ddiv->reg = list->reg;
605 		ddiv->shift0 = list->shift0;
606 		ddiv->width0 = list->width0;
607 		ddiv->shift1 = list->shift1;
608 		ddiv->width1 = list->width1;
609 		ddiv->shift_gate = list->shift_gate;
610 		ddiv->width_gate = list->width_gate;
611 		ddiv->shift2 = list->ex_shift;
612 		ddiv->width2 = list->ex_width;
613 		ddiv->flags = list->div_flags;
614 		ddiv->mult = 2;
615 		ddiv->div = 5;
616 		ddiv->hw.init = &init;
617 
618 		hw = &ddiv->hw;
619 		ret = devm_clk_hw_register(dev, hw);
620 		if (ret) {
621 			dev_err(dev, "register clk: %s failed!\n", list->name);
622 			return ret;
623 		}
624 		ctx->clk_data.hws[list->id] = hw;
625 	}
626 
627 	return 0;
628 }
629