xref: /freebsd/sys/dev/qcom_clk/qcom_clk_rcg2.c (revision 87384c51e047349fdbcf4f07fe52d900ce108040)
1 /*-
2  * Copyright (c) 2021 Adrian Chadd <adrian@FreeBSD.org>.
3  *
4  * Redistribution and use in source and binary forms, with or without
5  * modification, are permitted provided that the following conditions
6  * are met:
7  * 1. Redistributions of source code must retain the above copyright
8  *    notice, this list of conditions and the following disclaimer.
9  * 2. Redistributions in binary form must reproduce the above copyright
10  *    notice, this list of conditions and the following disclaimer in the
11  *    documentation and/or other materials provided with the distribution.
12  *
13  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
14  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
15  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
16  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
17  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
18  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
19  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
20  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
21  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
22  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
23  * SUCH DAMAGE.
24  */
25 
26 #include <sys/cdefs.h>
27 __FBSDID("$FreeBSD$");
28 
29 #include <sys/param.h>
30 #include <sys/systm.h>
31 #include <sys/bus.h>
32 #include <sys/lock.h>
33 #include <sys/mutex.h>
34 #include <sys/rman.h>
35 #include <machine/bus.h>
36 
37 #include <dev/extres/clk/clk.h>
38 #include <dev/extres/clk/clk_div.h>
39 #include <dev/extres/clk/clk_fixed.h>
40 #include <dev/extres/clk/clk_mux.h>
41 
42 #include "qcom_clk_freqtbl.h"
43 #include "qcom_clk_rcg2.h"
44 #include "qcom_clk_rcg2_reg.h"
45 
46 #include "clkdev_if.h"
47 
48 #if 0
49 #define DPRINTF(dev, msg...) device_printf(dev, msg);
50 #else
51 #define DPRINTF(dev, msg...)
52 #endif
53 
54 #define	QCOM_CLK_RCG2_CFG_OFFSET(sc)	\
55 	    ((sc)->cmd_rcgr + (sc)->cfg_offset + QCOM_CLK_RCG2_CFG_REG)
56 #define	QCOM_CLK_RCG2_CMD_REGISTER(sc)	\
57 	    ((sc)->cmd_rcgr + QCOM_CLK_RCG2_CMD_REG)
58 #define	QCOM_CLK_RCG2_M_OFFSET(sc)	\
59 	    ((sc)->cmd_rcgr + (sc)->cfg_offset + QCOM_CLK_RCG2_M_REG)
60 #define	QCOM_CLK_RCG2_N_OFFSET(sc)	\
61 	    ((sc)->cmd_rcgr + (sc)->cfg_offset + QCOM_CLK_RCG2_N_REG)
62 #define	QCOM_CLK_RCG2_D_OFFSET(sc)	\
63 	    ((sc)->cmd_rcgr + (sc)->cfg_offset + QCOM_CLK_RCG2_D_REG)
64 
65 struct qcom_clk_rcg2_sc {
66 	struct clknode *clknode;
67 	uint32_t cmd_rcgr;
68 	uint32_t hid_width;
69 	uint32_t mnd_width;
70 	int32_t safe_src_idx;
71 	uint32_t cfg_offset;
72 	int safe_pre_parent_idx;
73 	uint32_t flags;
74 	const struct qcom_clk_freq_tbl *freq_tbl;
75 };
76 
77 
78 /*
79  * Finish a clock update.
80  *
81  * This instructs the configuration to take effect.
82  */
83 static bool
84 qcom_clk_rcg2_update_config_locked(struct qcom_clk_rcg2_sc *sc)
85 {
86 	uint32_t reg, count;
87 
88 	/*
89 	 * Send "update" to the controller.
90 	 */
91 	CLKDEV_READ_4(clknode_get_device(sc->clknode),
92 	    QCOM_CLK_RCG2_CMD_REGISTER(sc), &reg);
93 	reg |= QCOM_CLK_RCG2_CMD_UPDATE;
94 	CLKDEV_WRITE_4(clknode_get_device(sc->clknode),
95 	    QCOM_CLK_RCG2_CMD_REGISTER(sc), reg);
96 	wmb();
97 
98 	/*
99 	 * Poll for completion of update.
100 	 */
101 	for (count = 0; count < 1000; count++) {
102 		CLKDEV_READ_4(clknode_get_device(sc->clknode),
103 		    QCOM_CLK_RCG2_CMD_REGISTER(sc), &reg);
104 		if ((reg & QCOM_CLK_RCG2_CMD_UPDATE) == 0) {
105 			return (true);
106 		}
107 		DELAY(10);
108 		rmb();
109 	}
110 
111 	CLKDEV_READ_4(clknode_get_device(sc->clknode),
112 	    QCOM_CLK_RCG2_CMD_REGISTER(sc), &reg);
113 	DPRINTF(clknode_get_device(sc->clknode), "%s: failed; reg=0x%08x\n",
114 	    __func__, reg);
115 	return (false);
116 }
117 
118 /*
119  * Calculate the output frequency given an input frequency and the m/n:d
120  * configuration.
121  */
122 static uint64_t
123 qcom_clk_rcg2_calc_rate(uint64_t rate, uint32_t mode, uint32_t m, uint32_t n,
124     uint32_t hid_div)
125 {
126 	if (hid_div != 0) {
127 		rate = rate * 2;
128 		rate = rate / (hid_div + 1);
129 	}
130 
131 	/* Note: assume n is not 0 here; bad things happen if it is */
132 
133 	if (mode != 0) {
134 		rate = (rate * m) / n;
135 	}
136 
137 	return (rate);
138 }
139 
140 /*
141  * The inverse of calc_rate() - calculate the required input frequency
142  * given the desired output freqency and m/n:d configuration.
143  */
144 static uint64_t
145 qcom_clk_rcg2_calc_input_freq(uint64_t freq, uint32_t m, uint32_t n,
146     uint32_t hid_div)
147 {
148 	if (hid_div != 0) {
149 		freq = freq / 2;
150 		freq = freq * (hid_div + 1);
151 	}
152 
153 	if (n != 0) {
154 		freq = (freq * n) / m;
155 	}
156 
157 	return (freq);
158 }
159 
160 static int
161 qcom_clk_rcg2_recalc(struct clknode *clk, uint64_t *freq)
162 {
163 	struct qcom_clk_rcg2_sc *sc;
164 	uint32_t cfg, m = 0, n = 0, hid_div = 0;
165 	uint32_t mode = 0, mask;
166 
167 	sc = clknode_get_softc(clk);
168 
169 	/* Read the MODE, CFG, M and N parameters */
170 	CLKDEV_DEVICE_LOCK(clknode_get_device(sc->clknode));
171 	CLKDEV_READ_4(clknode_get_device(sc->clknode),
172 	    QCOM_CLK_RCG2_CFG_OFFSET(sc),
173 	    &cfg);
174 	if (sc->mnd_width != 0) {
175 		mask = (1U << sc->mnd_width) - 1;
176 		CLKDEV_READ_4(clknode_get_device(sc->clknode),
177 		    QCOM_CLK_RCG2_M_OFFSET(sc), &m);
178 		CLKDEV_READ_4(clknode_get_device(sc->clknode),
179 		    QCOM_CLK_RCG2_N_OFFSET(sc), &n);
180 		m = m & mask;
181 		n = ~ n;
182 		n = n & mask;
183 		n = n + m;
184 		mode = (cfg & QCOM_CLK_RCG2_CFG_MODE_MASK)
185 		    >> QCOM_CLK_RCG2_CFG_MODE_SHIFT;
186 	}
187 	CLKDEV_DEVICE_UNLOCK(clknode_get_device(sc->clknode));
188 
189 	/* Fetch the divisor */
190 	mask = (1U << sc->hid_width) - 1;
191 	hid_div = (cfg >> QCOM_CLK_RCG2_CFG_SRC_DIV_SHIFT) & mask;
192 
193 	/* Calculate the rate based on the parent rate and config */
194 	*freq = qcom_clk_rcg2_calc_rate(*freq, mode, m, n, hid_div);
195 
196 	return (0);
197 }
198 
199 /*
200  * configure the mn:d divisor, pre-divisor, and parent.
201  */
202 static void
203 qcom_clk_rcg2_set_config_locked(struct qcom_clk_rcg2_sc *sc,
204     const struct qcom_clk_freq_tbl *f, int parent_idx)
205 {
206 	uint32_t mask, reg;
207 
208 	/* If we have MN:D, then update it */
209 	if (sc->mnd_width != 0 && f->n != 0) {
210 		mask = (1U << sc->mnd_width) - 1;
211 
212 		CLKDEV_READ_4(clknode_get_device(sc->clknode),
213 		    QCOM_CLK_RCG2_M_OFFSET(sc), &reg);
214 		reg &= ~mask;
215 		reg |= (f->m & mask);
216 		CLKDEV_WRITE_4(clknode_get_device(sc->clknode),
217 		    QCOM_CLK_RCG2_M_OFFSET(sc), reg);
218 
219 		CLKDEV_READ_4(clknode_get_device(sc->clknode),
220 		    QCOM_CLK_RCG2_N_OFFSET(sc), &reg);
221 		reg &= ~mask;
222 		reg |= ((~(f->n - f->m)) & mask);
223 		CLKDEV_WRITE_4(clknode_get_device(sc->clknode),
224 		    QCOM_CLK_RCG2_N_OFFSET(sc), reg);
225 
226 		CLKDEV_READ_4(clknode_get_device(sc->clknode),
227 		    QCOM_CLK_RCG2_D_OFFSET(sc), &reg);
228 		reg &= ~mask;
229 		reg |= ((~f->n) & mask);
230 		CLKDEV_WRITE_4(clknode_get_device(sc->clknode),
231 		    QCOM_CLK_RCG2_D_OFFSET(sc), reg);
232 	}
233 
234 	mask = (1U << sc->hid_width) - 1;
235 	/*
236 	 * Mask out register fields we're going to modify along with
237 	 * the pre-divisor.
238 	 */
239 	mask |= QCOM_CLK_RCG2_CFG_SRC_SEL_MASK
240 	    | QCOM_CLK_RCG2_CFG_MODE_MASK
241 	    | QCOM_CLK_RCG2_CFG_HW_CLK_CTRL_MASK;
242 
243 	CLKDEV_READ_4(clknode_get_device(sc->clknode),
244 	    QCOM_CLK_RCG2_CFG_OFFSET(sc), &reg);
245 	reg &= ~mask;
246 
247 	/* Configure pre-divisor */
248 	reg = reg | ((f->pre_div) << QCOM_CLK_RCG2_CFG_SRC_DIV_SHIFT);
249 
250 	/* Configure parent clock */
251 	reg = reg | (((parent_idx << QCOM_CLK_RCG2_CFG_SRC_SEL_SHIFT)
252 	    & QCOM_CLK_RCG2_CFG_SRC_SEL_MASK));
253 
254 	/* Configure dual-edge if needed */
255 	if (sc->mnd_width != 0 && f->n != 0 && (f->m != f->n))
256 		reg |= QCOM_CLK_RCG2_CFG_MODE_DUAL_EDGE;
257 
258 	CLKDEV_WRITE_4(clknode_get_device(sc->clknode),
259 	    QCOM_CLK_RCG2_CFG_OFFSET(sc), reg);
260 }
261 
262 static int
263 qcom_clk_rcg2_init(struct clknode *clk, device_t dev)
264 {
265 	struct qcom_clk_rcg2_sc *sc;
266 	uint32_t reg;
267 	uint32_t idx;
268 	bool enabled __unused;
269 
270 	sc = clknode_get_softc(clk);
271 
272 	/*
273 	 * Read the mux setting to set the right parent.
274 	 * Whilst here, read the config to get whether we're enabled
275 	 * or not.
276 	 */
277 	CLKDEV_DEVICE_LOCK(clknode_get_device(sc->clknode));
278 	/* check if rcg2 root clock is enabled */
279 	CLKDEV_READ_4(clknode_get_device(sc->clknode),
280 	    QCOM_CLK_RCG2_CMD_REGISTER(sc), &reg);
281 	if (reg & QCOM_CLK_RCG2_CMD_ROOT_OFF)
282 		enabled = false;
283 	else
284 		enabled = true;
285 
286 	/* mux settings */
287 	CLKDEV_READ_4(clknode_get_device(sc->clknode),
288 	    QCOM_CLK_RCG2_CFG_OFFSET(sc), &reg);
289 	CLKDEV_DEVICE_UNLOCK(clknode_get_device(sc->clknode));
290 
291 	idx = (reg & QCOM_CLK_RCG2_CFG_SRC_SEL_MASK)
292 	    >> QCOM_CLK_RCG2_CFG_SRC_SEL_SHIFT;
293 	DPRINTF(clknode_get_device(sc->clknode),
294 	    "%s: mux index %u, enabled=%d\n",
295 	    __func__, idx, enabled);
296 	clknode_init_parent_idx(clk, idx);
297 
298 	/*
299 	 * If we could be sure our parent clocks existed here in the tree,
300 	 * we could calculate our current frequency by fetching the parent
301 	 * frequency and then do our divider math.  Unfortunately that
302 	 * currently isn't the case.
303 	 */
304 
305 	return(0);
306 }
307 
308 static int
309 qcom_clk_rcg2_set_gate(struct clknode *clk, bool enable)
310 {
311 
312 	/*
313 	 * For now this isn't supported; there's some support for
314 	 * "shared" rcg2 nodes in the Qualcomm/upstream Linux trees but
315 	 * it's not currently needed for the supported platforms.
316 	 */
317 	return (0);
318 }
319 
320 /*
321  * Program the parent index.
322  *
323  * This doesn't do the update.  It also must be called with the device
324  * lock held.
325  */
326 static void
327 qcom_clk_rcg2_set_parent_index_locked(struct qcom_clk_rcg2_sc *sc,
328     uint32_t index)
329 {
330 	uint32_t reg;
331 
332 	CLKDEV_READ_4(clknode_get_device(sc->clknode),
333 	    QCOM_CLK_RCG2_CFG_OFFSET(sc), &reg);
334 	reg = reg & ~QCOM_CLK_RCG2_CFG_SRC_SEL_MASK;
335 	reg = reg | (((index << QCOM_CLK_RCG2_CFG_SRC_SEL_SHIFT)
336 	    & QCOM_CLK_RCG2_CFG_SRC_SEL_MASK));
337 	CLKDEV_WRITE_4(clknode_get_device(sc->clknode),
338 	    QCOM_CLK_RCG2_CFG_OFFSET(sc),
339 	    reg);
340 }
341 
342 /*
343  * Set frequency
344  *
345  * fin - the parent frequency, if exists
346  * fout - starts as the requested frequency, ends with the configured
347  *        or dry-run frequency
348  * Flags - CLK_SET_DRYRUN, CLK_SET_ROUND_UP, CLK_SET_ROUND_DOWN
349  * retval - 0, ERANGE
350  */
351 static int
352 qcom_clk_rcg2_set_freq(struct clknode *clk, uint64_t fin, uint64_t *fout,
353     int flags, int *stop)
354 {
355 	struct qcom_clk_rcg2_sc *sc;
356 	const struct qcom_clk_freq_tbl *f;
357 	const char **parent_names;
358 	uint64_t p_freq, p_clk_freq;
359 	int parent_cnt;
360 	struct clknode *p_clk;
361 	int i;
362 
363 	sc = clknode_get_softc(clk);
364 
365 	/*
366 	 * Find a suitable frequency in the frequency table.
367 	 *
368 	 * TODO: should pay attention to ROUND_UP / ROUND_DOWN and add
369 	 * a freqtbl method to handle both accordingly.
370 	 */
371 	f = qcom_clk_freq_tbl_lookup(sc->freq_tbl, *fout);
372 	if (f == NULL) {
373 		device_printf(clknode_get_device(sc->clknode),
374 		    "%s: no suitable freqtbl entry found for freq %llu\n",
375 		    __func__,
376 		    *fout);
377 		return (ERANGE);
378 	}
379 
380 	/*
381 	 * Find the parent index for the given parent clock.
382 	 * Abort if we can't actually find it.
383 	 *
384 	 * XXX TODO: this should be a clk API call!
385 	 */
386 	parent_cnt = clknode_get_parents_num(clk);
387 	parent_names = clknode_get_parent_names(clk);
388 	for (i = 0; i < parent_cnt; i++) {
389 		if (parent_names[i] == NULL)
390 			continue;
391 		if (strcmp(parent_names[i], f->parent) == 0)
392 			break;
393 	}
394 	if (i >= parent_cnt) {
395 		device_printf(clknode_get_device(sc->clknode),
396 		    "%s: couldn't find suitable parent?\n",
397 		    __func__);
398 		return (ENXIO);
399 	}
400 
401 	/*
402 	 * If we aren't setting the parent clock, then we need
403 	 * to just program the new parent clock in and update.
404 	 * (or for DRYRUN just skip that and return the new
405 	 * frequency.)
406 	 */
407 	if ((sc->flags & QCOM_CLK_RCG2_FLAGS_SET_RATE_PARENT) == 0) {
408 		if (flags & CLK_SET_DRYRUN) {
409 			*fout = f->freq;
410 			return (0);
411 		}
412 
413 		if (sc->safe_pre_parent_idx > -1) {
414 			DPRINTF(clknode_get_device(sc->clknode),
415 			    "%s: setting to safe parent idx %d\n",
416 			    __func__,
417 			    sc->safe_pre_parent_idx);
418 			CLKDEV_DEVICE_LOCK(clknode_get_device(sc->clknode));
419 			qcom_clk_rcg2_set_parent_index_locked(sc,
420 			    sc->safe_pre_parent_idx);
421 			DPRINTF(clknode_get_device(sc->clknode),
422 			    "%s: safe parent: updating config\n", __func__);
423 			if (! qcom_clk_rcg2_update_config_locked(sc)) {
424 				CLKDEV_DEVICE_UNLOCK(clknode_get_device(sc->clknode));
425 				DPRINTF(clknode_get_device(sc->clknode),
426 				    "%s: error updating config\n",
427 				    __func__);
428 				return (ENXIO);
429 			}
430 			CLKDEV_DEVICE_UNLOCK(clknode_get_device(sc->clknode));
431 			DPRINTF(clknode_get_device(sc->clknode),
432 			    "%s: safe parent: done\n", __func__);
433 			clknode_set_parent_by_idx(sc->clknode,
434 			    sc->safe_pre_parent_idx);
435 		}
436 		/* Program parent index, then schedule update */
437 		CLKDEV_DEVICE_LOCK(clknode_get_device(sc->clknode));
438 		qcom_clk_rcg2_set_parent_index_locked(sc, i);
439 		if (! qcom_clk_rcg2_update_config_locked(sc)) {
440 			CLKDEV_DEVICE_UNLOCK(clknode_get_device(sc->clknode));
441 			device_printf(clknode_get_device(sc->clknode),
442 			    "%s: couldn't program in parent idx %u!\n",
443 			    __func__, i);
444 			return (ENXIO);
445 		}
446 		CLKDEV_DEVICE_UNLOCK(clknode_get_device(sc->clknode));
447 		clknode_set_parent_by_idx(sc->clknode, i);
448 		*fout = f->freq;
449 		return (0);
450 	}
451 
452 	/*
453 	 * If we /are/ setting the parent clock, then we need
454 	 * to determine what frequency we need the parent to
455 	 * be, and then reconfigure the parent to the new
456 	 * frequency, and then change our parent.
457 	 *
458 	 * (Again, if we're doing DRYRUN, just skip that
459 	 * and return the new frequency.)
460 	 */
461 	p_clk = clknode_find_by_name(f->parent);
462 	if (p_clk == NULL) {
463 		device_printf(clknode_get_device(sc->clknode),
464 		    "%s: couldn't find parent clk (%s)\n",
465 		    __func__, f->parent);
466 		return (ENXIO);
467 	}
468 
469 	/*
470 	 * Calculate required frequency from said parent clock to
471 	 * meet the needs of our target clock.
472 	 */
473 	p_freq = qcom_clk_rcg2_calc_input_freq(f->freq, f->m, f->n,
474 	    f->pre_div);
475 	DPRINTF(clknode_get_device(sc->clknode),
476 	    "%s: request %llu, parent %s freq %llu, parent freq %llu\n",
477 	    __func__,
478 	    *fout,
479 	    f->parent,
480 	    f->freq,
481 	    p_freq);
482 
483 	/*
484 	 * To ensure glitch-free operation on some clocks, set it to
485 	 * a safe parent before programming our divisor and the parent
486 	 * clock configuration.  Then once it's done, flip the parent
487 	 * to the new parent.
488 	 *
489 	 * If we're doing a dry-run then we don't need to re-parent the
490 	 * clock just yet!
491 	 */
492 	if (((flags & CLK_SET_DRYRUN) == 0) &&
493 	    (sc->safe_pre_parent_idx > -1)) {
494 		DPRINTF(clknode_get_device(sc->clknode),
495 		    "%s: setting to safe parent idx %d\n",
496 		    __func__,
497 		    sc->safe_pre_parent_idx);
498 		CLKDEV_DEVICE_LOCK(clknode_get_device(sc->clknode));
499 		qcom_clk_rcg2_set_parent_index_locked(sc,
500 		    sc->safe_pre_parent_idx);
501 		DPRINTF(clknode_get_device(sc->clknode),
502 		    "%s: safe parent: updating config\n", __func__);
503 		if (! qcom_clk_rcg2_update_config_locked(sc)) {
504 			CLKDEV_DEVICE_UNLOCK(clknode_get_device(sc->clknode));
505 			DPRINTF(clknode_get_device(sc->clknode),
506 			    "%s: error updating config\n",
507 			    __func__);
508 			return (ENXIO);
509 		}
510 		CLKDEV_DEVICE_UNLOCK(clknode_get_device(sc->clknode));
511 		DPRINTF(clknode_get_device(sc->clknode),
512 		    "%s: safe parent: done\n", __func__);
513 		clknode_set_parent_by_idx(sc->clknode,
514 		    sc->safe_pre_parent_idx);
515 	}
516 
517 	/*
518 	 * Set the parent frequency before we change our mux and divisor
519 	 * configuration.
520 	 */
521 	if (clknode_get_freq(p_clk, &p_clk_freq) != 0) {
522 		device_printf(clknode_get_device(sc->clknode),
523 		    "%s: couldn't get freq for parent clock %s\n",
524 		    __func__,
525 		    f->parent);
526 		return (ENXIO);
527 	}
528 	if (p_clk_freq != p_freq) {
529 		uint64_t n_freq;
530 		int rv;
531 
532 		/*
533 		 * If we're doing a dryrun then call test_freq() not set_freq().
534 		 * That way we get the frequency back that we would be set to.
535 		 *
536 		 * If we're not doing a dry run then set the frequency, then
537 		 * call get_freq to get what it was set to.
538 		 */
539 		if (flags & CLK_SET_DRYRUN) {
540 			n_freq = p_freq;
541 			rv = clknode_test_freq(p_clk, n_freq, flags, 0,
542 			    &p_freq);
543 		} else {
544 			rv = clknode_set_freq(p_clk, p_freq, flags, 0);
545 		}
546 
547 		if (rv != 0) {
548 			device_printf(clknode_get_device(sc->clknode),
549 			    "%s: couldn't set parent clock %s frequency to "
550 			    "%llu\n",
551 			    __func__,
552 			    f->parent,
553 			    p_freq);
554 			return (ENXIO);
555 		}
556 
557 		/* Frequency was set, fetch what it was set to */
558 		if ((flags & CLK_SET_DRYRUN) == 0) {
559 			rv = clknode_get_freq(p_clk, &p_freq);
560 			if (rv != 0) {
561 				device_printf(clknode_get_device(sc->clknode),
562 				    "%s: couldn't get parent frequency",
563 				    __func__);
564 				return (ENXIO);
565 			}
566 		}
567 	}
568 
569 	DPRINTF(clknode_get_device(sc->clknode),
570 	    "%s: requsted freq=%llu, target freq=%llu,"
571 	    " parent choice=%s, parent_freq=%llu\n",
572 	    __func__,
573 	    *fout,
574 	    f->freq,
575 	    f->parent,
576 	    p_freq);
577 
578 	/*
579 	 * Set the parent node, the parent programming and the divisor
580 	 * config.  Because they're done together, we don't go via
581 	 * a mux method on this node.
582 	 */
583 
584 	/*
585 	 * Program the divisor and parent.
586 	 */
587 	if ((flags & CLK_SET_DRYRUN) == 0) {
588 		CLKDEV_DEVICE_LOCK(clknode_get_device(sc->clknode));
589 		qcom_clk_rcg2_set_config_locked(sc, f, i);
590 		if (! qcom_clk_rcg2_update_config_locked(sc)) {
591 			CLKDEV_DEVICE_UNLOCK(clknode_get_device(sc->clknode));
592 			device_printf(clknode_get_device(sc->clknode),
593 			    "%s: couldn't program in divisor, help!\n",
594 			    __func__);
595 			return (ENXIO);
596 		}
597 		CLKDEV_DEVICE_UNLOCK(clknode_get_device(sc->clknode));
598 		clknode_set_parent_by_idx(sc->clknode, i);
599 	}
600 
601 	/*
602 	 * p_freq is now the frequency that the parent /is/ set to.
603 	 * (Or would be set to for a dry run.)
604 	 *
605 	 * Calculate what the eventual frequency would be, we'll want
606 	 * this to return when we're done - and again, if it's a dryrun,
607 	 * don't set anything up.  This doesn't rely on the register
608 	 * contents.
609 	 */
610 	*fout = qcom_clk_rcg2_calc_rate(p_freq, (f->n == 0 ? 0 : 1),
611 	    f->m, f->n, f->pre_div);
612 
613 	return (0);
614 }
615 
616 static clknode_method_t qcom_clk_rcg2_methods[] = {
617 	/* Device interface */
618 	CLKNODEMETHOD(clknode_init,		qcom_clk_rcg2_init),
619 	CLKNODEMETHOD(clknode_recalc_freq,	qcom_clk_rcg2_recalc),
620 	CLKNODEMETHOD(clknode_set_gate,		qcom_clk_rcg2_set_gate),
621 	CLKNODEMETHOD(clknode_set_freq,		qcom_clk_rcg2_set_freq),
622 	CLKNODEMETHOD_END
623 };
624 
625 DEFINE_CLASS_1(qcom_clk_fepll, qcom_clk_rcg2_class, qcom_clk_rcg2_methods,
626    sizeof(struct qcom_clk_rcg2_sc), clknode_class);
627 
628 int
629 qcom_clk_rcg2_register(struct clkdom *clkdom,
630     struct qcom_clk_rcg2_def *clkdef)
631 {
632 	struct clknode *clk;
633 	struct qcom_clk_rcg2_sc *sc;
634 
635 	/*
636 	 * Right now the rcg2 code isn't supporting turning off the clock
637 	 * or limiting it to the lowest parent clock.  But, do set the
638 	 * flags appropriately.
639 	 */
640 	if (clkdef->flags & QCOM_CLK_RCG2_FLAGS_CRITICAL)
641 		clkdef->clkdef.flags |= CLK_NODE_CANNOT_STOP;
642 
643 	clk = clknode_create(clkdom, &qcom_clk_rcg2_class, &clkdef->clkdef);
644 	if (clk == NULL)
645 		return (1);
646 
647 	sc = clknode_get_softc(clk);
648 	sc->clknode = clk;
649 
650 	sc->cmd_rcgr = clkdef->cmd_rcgr;
651 	sc->hid_width = clkdef->hid_width;
652 	sc->mnd_width = clkdef->mnd_width;
653 	sc->safe_src_idx = clkdef->safe_src_idx;
654 	sc->safe_pre_parent_idx = clkdef->safe_pre_parent_idx;
655 	sc->cfg_offset = clkdef->cfg_offset;
656 	sc->flags = clkdef->flags;
657 	sc->freq_tbl = clkdef->freq_tbl;
658 
659 	clknode_register(clkdom, clk);
660 
661 	return (0);
662 }
663