1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * OMAP3/4 - specific DPLL control functions
4 *
5 * Copyright (C) 2009-2010 Texas Instruments, Inc.
6 * Copyright (C) 2009-2010 Nokia Corporation
7 *
8 * Written by Paul Walmsley
9 * Testing and integration fixes by Jouni Högander
10 *
11 * 36xx support added by Vishwanath BS, Richard Woodruff, and Nishanth
12 * Menon
13 *
14 * Parts of this code are based on code written by
15 * Richard Woodruff, Tony Lindgren, Tuukka Tikkanen, Karthik Dasu
16 */
17
18 #include <linux/kernel.h>
19 #include <linux/device.h>
20 #include <linux/list.h>
21 #include <linux/errno.h>
22 #include <linux/delay.h>
23 #include <linux/clk.h>
24 #include <linux/io.h>
25 #include <linux/bitops.h>
26 #include <linux/clkdev.h>
27 #include <linux/clk/ti.h>
28
29 #include "clock.h"
30
31 /* CM_AUTOIDLE_PLL*.AUTO_* bit values */
32 #define DPLL_AUTOIDLE_DISABLE 0x0
33 #define DPLL_AUTOIDLE_LOW_POWER_STOP 0x1
34
35 #define MAX_DPLL_WAIT_TRIES 1000000
36
37 #define OMAP3XXX_EN_DPLL_LOCKED 0x7
38
39 /* Forward declarations */
40 static u32 omap3_dpll_autoidle_read(struct clk_hw_omap *clk);
41 static void omap3_dpll_deny_idle(struct clk_hw_omap *clk);
42 static void omap3_dpll_allow_idle(struct clk_hw_omap *clk);
43
44 /* Private functions */
45
46 /* _omap3_dpll_write_clken - write clken_bits arg to a DPLL's enable bits */
_omap3_dpll_write_clken(struct clk_hw_omap * clk,u8 clken_bits)47 static void _omap3_dpll_write_clken(struct clk_hw_omap *clk, u8 clken_bits)
48 {
49 const struct dpll_data *dd;
50 u32 v;
51
52 dd = clk->dpll_data;
53
54 v = ti_clk_ll_ops->clk_readl(&dd->control_reg);
55 v &= ~dd->enable_mask;
56 v |= clken_bits << __ffs(dd->enable_mask);
57 ti_clk_ll_ops->clk_writel(v, &dd->control_reg);
58 }
59
60 /* _omap3_wait_dpll_status: wait for a DPLL to enter a specific state */
_omap3_wait_dpll_status(struct clk_hw_omap * clk,u8 state)61 static int _omap3_wait_dpll_status(struct clk_hw_omap *clk, u8 state)
62 {
63 const struct dpll_data *dd;
64 int i = 0;
65 int ret = -EINVAL;
66 const char *clk_name;
67
68 dd = clk->dpll_data;
69 clk_name = clk_hw_get_name(&clk->hw);
70
71 state <<= __ffs(dd->idlest_mask);
72
73 while (((ti_clk_ll_ops->clk_readl(&dd->idlest_reg) & dd->idlest_mask)
74 != state) && i < MAX_DPLL_WAIT_TRIES) {
75 i++;
76 udelay(1);
77 }
78
79 if (i == MAX_DPLL_WAIT_TRIES) {
80 pr_err("clock: %s failed transition to '%s'\n",
81 clk_name, (state) ? "locked" : "bypassed");
82 } else {
83 pr_debug("clock: %s transition to '%s' in %d loops\n",
84 clk_name, (state) ? "locked" : "bypassed", i);
85
86 ret = 0;
87 }
88
89 return ret;
90 }
91
92 /* From 3430 TRM ES2 4.7.6.2 */
_omap3_dpll_compute_freqsel(struct clk_hw_omap * clk,u8 n)93 static u16 _omap3_dpll_compute_freqsel(struct clk_hw_omap *clk, u8 n)
94 {
95 unsigned long fint;
96 u16 f = 0;
97
98 fint = clk_hw_get_rate(clk->dpll_data->clk_ref) / n;
99
100 pr_debug("clock: fint is %lu\n", fint);
101
102 if (fint >= 750000 && fint <= 1000000)
103 f = 0x3;
104 else if (fint > 1000000 && fint <= 1250000)
105 f = 0x4;
106 else if (fint > 1250000 && fint <= 1500000)
107 f = 0x5;
108 else if (fint > 1500000 && fint <= 1750000)
109 f = 0x6;
110 else if (fint > 1750000 && fint <= 2100000)
111 f = 0x7;
112 else if (fint > 7500000 && fint <= 10000000)
113 f = 0xB;
114 else if (fint > 10000000 && fint <= 12500000)
115 f = 0xC;
116 else if (fint > 12500000 && fint <= 15000000)
117 f = 0xD;
118 else if (fint > 15000000 && fint <= 17500000)
119 f = 0xE;
120 else if (fint > 17500000 && fint <= 21000000)
121 f = 0xF;
122 else
123 pr_debug("clock: unknown freqsel setting for %d\n", n);
124
125 return f;
126 }
127
128 /*
129 * _omap3_noncore_dpll_lock - instruct a DPLL to lock and wait for readiness
130 * @clk: pointer to a DPLL struct clk
131 *
132 * Instructs a non-CORE DPLL to lock. Waits for the DPLL to report
133 * readiness before returning. Will save and restore the DPLL's
134 * autoidle state across the enable, per the CDP code. If the DPLL
135 * locked successfully, return 0; if the DPLL did not lock in the time
136 * allotted, or DPLL3 was passed in, return -EINVAL.
137 */
_omap3_noncore_dpll_lock(struct clk_hw_omap * clk)138 static int _omap3_noncore_dpll_lock(struct clk_hw_omap *clk)
139 {
140 const struct dpll_data *dd;
141 u8 ai;
142 u8 state = 1;
143 int r = 0;
144
145 pr_debug("clock: locking DPLL %s\n", clk_hw_get_name(&clk->hw));
146
147 dd = clk->dpll_data;
148 state <<= __ffs(dd->idlest_mask);
149
150 /* Check if already locked */
151 if ((ti_clk_ll_ops->clk_readl(&dd->idlest_reg) & dd->idlest_mask) ==
152 state)
153 goto done;
154
155 ai = omap3_dpll_autoidle_read(clk);
156
157 if (ai)
158 omap3_dpll_deny_idle(clk);
159
160 _omap3_dpll_write_clken(clk, DPLL_LOCKED);
161
162 r = _omap3_wait_dpll_status(clk, 1);
163
164 if (ai)
165 omap3_dpll_allow_idle(clk);
166
167 done:
168 return r;
169 }
170
171 /*
172 * _omap3_noncore_dpll_bypass - instruct a DPLL to bypass and wait for readiness
173 * @clk: pointer to a DPLL struct clk
174 *
175 * Instructs a non-CORE DPLL to enter low-power bypass mode. In
176 * bypass mode, the DPLL's rate is set equal to its parent clock's
177 * rate. Waits for the DPLL to report readiness before returning.
178 * Will save and restore the DPLL's autoidle state across the enable,
179 * per the CDP code. If the DPLL entered bypass mode successfully,
180 * return 0; if the DPLL did not enter bypass in the time allotted, or
181 * DPLL3 was passed in, or the DPLL does not support low-power bypass,
182 * return -EINVAL.
183 */
_omap3_noncore_dpll_bypass(struct clk_hw_omap * clk)184 static int _omap3_noncore_dpll_bypass(struct clk_hw_omap *clk)
185 {
186 int r;
187 u8 ai;
188
189 if (!(clk->dpll_data->modes & (1 << DPLL_LOW_POWER_BYPASS)))
190 return -EINVAL;
191
192 pr_debug("clock: configuring DPLL %s for low-power bypass\n",
193 clk_hw_get_name(&clk->hw));
194
195 ai = omap3_dpll_autoidle_read(clk);
196
197 _omap3_dpll_write_clken(clk, DPLL_LOW_POWER_BYPASS);
198
199 r = _omap3_wait_dpll_status(clk, 0);
200
201 if (ai)
202 omap3_dpll_allow_idle(clk);
203
204 return r;
205 }
206
207 /*
208 * _omap3_noncore_dpll_stop - instruct a DPLL to stop
209 * @clk: pointer to a DPLL struct clk
210 *
211 * Instructs a non-CORE DPLL to enter low-power stop. Will save and
212 * restore the DPLL's autoidle state across the stop, per the CDP
213 * code. If DPLL3 was passed in, or the DPLL does not support
214 * low-power stop, return -EINVAL; otherwise, return 0.
215 */
_omap3_noncore_dpll_stop(struct clk_hw_omap * clk)216 static int _omap3_noncore_dpll_stop(struct clk_hw_omap *clk)
217 {
218 u8 ai;
219
220 if (!(clk->dpll_data->modes & (1 << DPLL_LOW_POWER_STOP)))
221 return -EINVAL;
222
223 pr_debug("clock: stopping DPLL %s\n", clk_hw_get_name(&clk->hw));
224
225 ai = omap3_dpll_autoidle_read(clk);
226
227 _omap3_dpll_write_clken(clk, DPLL_LOW_POWER_STOP);
228
229 if (ai)
230 omap3_dpll_allow_idle(clk);
231
232 return 0;
233 }
234
235 /**
236 * _lookup_dco - Lookup DCO used by j-type DPLL
237 * @clk: pointer to a DPLL struct clk
238 * @dco: digital control oscillator selector
239 * @m: DPLL multiplier to set
240 * @n: DPLL divider to set
241 *
242 * See 36xx TRM section 3.5.3.3.3.2 "Type B DPLL (Low-Jitter)"
243 *
244 * XXX This code is not needed for 3430/AM35xx; can it be optimized
245 * out in non-multi-OMAP builds for those chips?
246 */
_lookup_dco(struct clk_hw_omap * clk,u8 * dco,u16 m,u8 n)247 static void _lookup_dco(struct clk_hw_omap *clk, u8 *dco, u16 m, u8 n)
248 {
249 unsigned long fint, clkinp; /* watch out for overflow */
250
251 clkinp = clk_hw_get_rate(clk_hw_get_parent(&clk->hw));
252 fint = (clkinp / n) * m;
253
254 if (fint < 1000000000)
255 *dco = 2;
256 else
257 *dco = 4;
258 }
259
260 /**
261 * _lookup_sddiv - Calculate sigma delta divider for j-type DPLL
262 * @clk: pointer to a DPLL struct clk
263 * @sd_div: target sigma-delta divider
264 * @m: DPLL multiplier to set
265 * @n: DPLL divider to set
266 *
267 * See 36xx TRM section 3.5.3.3.3.2 "Type B DPLL (Low-Jitter)"
268 *
269 * XXX This code is not needed for 3430/AM35xx; can it be optimized
270 * out in non-multi-OMAP builds for those chips?
271 */
_lookup_sddiv(struct clk_hw_omap * clk,u8 * sd_div,u16 m,u8 n)272 static void _lookup_sddiv(struct clk_hw_omap *clk, u8 *sd_div, u16 m, u8 n)
273 {
274 unsigned long clkinp, sd; /* watch out for overflow */
275 int mod1, mod2;
276
277 clkinp = clk_hw_get_rate(clk_hw_get_parent(&clk->hw));
278
279 /*
280 * target sigma-delta to near 250MHz
281 * sd = ceil[(m/(n+1)) * (clkinp_MHz / 250)]
282 */
283 clkinp /= 100000; /* shift from MHz to 10*Hz for 38.4 and 19.2 */
284 mod1 = (clkinp * m) % (250 * n);
285 sd = (clkinp * m) / (250 * n);
286 mod2 = sd % 10;
287 sd /= 10;
288
289 if (mod1 || mod2)
290 sd++;
291 *sd_div = sd;
292 }
293
294 /*
295 * _omap3_noncore_dpll_program - set non-core DPLL M,N values directly
296 * @clk: struct clk * of DPLL to set
297 * @freqsel: FREQSEL value to set
298 *
299 * Program the DPLL with the last M, N values calculated, and wait for
300 * the DPLL to lock. Returns -EINVAL upon error, or 0 upon success.
301 */
omap3_noncore_dpll_program(struct clk_hw_omap * clk,u16 freqsel)302 static int omap3_noncore_dpll_program(struct clk_hw_omap *clk, u16 freqsel)
303 {
304 struct dpll_data *dd = clk->dpll_data;
305 u8 dco, sd_div, ai = 0;
306 u32 v;
307 bool errata_i810;
308
309 /* 3430 ES2 TRM: 4.7.6.9 DPLL Programming Sequence */
310 _omap3_noncore_dpll_bypass(clk);
311
312 /*
313 * Set jitter correction. Jitter correction applicable for OMAP343X
314 * only since freqsel field is no longer present on other devices.
315 */
316 if (ti_clk_get_features()->flags & TI_CLK_DPLL_HAS_FREQSEL) {
317 v = ti_clk_ll_ops->clk_readl(&dd->control_reg);
318 v &= ~dd->freqsel_mask;
319 v |= freqsel << __ffs(dd->freqsel_mask);
320 ti_clk_ll_ops->clk_writel(v, &dd->control_reg);
321 }
322
323 /* Set DPLL multiplier, divider */
324 v = ti_clk_ll_ops->clk_readl(&dd->mult_div1_reg);
325
326 /* Handle Duty Cycle Correction */
327 if (dd->dcc_mask) {
328 if (dd->last_rounded_rate >= dd->dcc_rate)
329 v |= dd->dcc_mask; /* Enable DCC */
330 else
331 v &= ~dd->dcc_mask; /* Disable DCC */
332 }
333
334 v &= ~(dd->mult_mask | dd->div1_mask);
335 v |= dd->last_rounded_m << __ffs(dd->mult_mask);
336 v |= (dd->last_rounded_n - 1) << __ffs(dd->div1_mask);
337
338 /* Configure dco and sd_div for dplls that have these fields */
339 if (dd->dco_mask) {
340 _lookup_dco(clk, &dco, dd->last_rounded_m, dd->last_rounded_n);
341 v &= ~(dd->dco_mask);
342 v |= dco << __ffs(dd->dco_mask);
343 }
344 if (dd->sddiv_mask) {
345 _lookup_sddiv(clk, &sd_div, dd->last_rounded_m,
346 dd->last_rounded_n);
347 v &= ~(dd->sddiv_mask);
348 v |= sd_div << __ffs(dd->sddiv_mask);
349 }
350
351 /*
352 * Errata i810 - DPLL controller can get stuck while transitioning
353 * to a power saving state. Software must ensure the DPLL can not
354 * transition to a low power state while changing M/N values.
355 * Easiest way to accomplish this is to prevent DPLL autoidle
356 * before doing the M/N re-program.
357 */
358 errata_i810 = ti_clk_get_features()->flags & TI_CLK_ERRATA_I810;
359
360 if (errata_i810) {
361 ai = omap3_dpll_autoidle_read(clk);
362 if (ai) {
363 omap3_dpll_deny_idle(clk);
364
365 /* OCP barrier */
366 omap3_dpll_autoidle_read(clk);
367 }
368 }
369
370 ti_clk_ll_ops->clk_writel(v, &dd->mult_div1_reg);
371
372 /* Set 4X multiplier and low-power mode */
373 if (dd->m4xen_mask || dd->lpmode_mask) {
374 v = ti_clk_ll_ops->clk_readl(&dd->control_reg);
375
376 if (dd->m4xen_mask) {
377 if (dd->last_rounded_m4xen)
378 v |= dd->m4xen_mask;
379 else
380 v &= ~dd->m4xen_mask;
381 }
382
383 if (dd->lpmode_mask) {
384 if (dd->last_rounded_lpmode)
385 v |= dd->lpmode_mask;
386 else
387 v &= ~dd->lpmode_mask;
388 }
389
390 ti_clk_ll_ops->clk_writel(v, &dd->control_reg);
391 }
392
393 /* We let the clock framework set the other output dividers later */
394
395 /* REVISIT: Set ramp-up delay? */
396
397 _omap3_noncore_dpll_lock(clk);
398
399 if (errata_i810 && ai)
400 omap3_dpll_allow_idle(clk);
401
402 return 0;
403 }
404
405 /* Public functions */
406
407 /**
408 * omap3_dpll_recalc - recalculate DPLL rate
409 * @clk: DPLL struct clk
410 *
411 * Recalculate and propagate the DPLL rate.
412 */
omap3_dpll_recalc(struct clk_hw * hw,unsigned long parent_rate)413 unsigned long omap3_dpll_recalc(struct clk_hw *hw, unsigned long parent_rate)
414 {
415 struct clk_hw_omap *clk = to_clk_hw_omap(hw);
416
417 return omap2_get_dpll_rate(clk);
418 }
419
420 /* Non-CORE DPLL (e.g., DPLLs that do not control SDRC) clock functions */
421
422 /**
423 * omap3_noncore_dpll_enable - instruct a DPLL to enter bypass or lock mode
424 * @clk: pointer to a DPLL struct clk
425 *
426 * Instructs a non-CORE DPLL to enable, e.g., to enter bypass or lock.
427 * The choice of modes depends on the DPLL's programmed rate: if it is
428 * the same as the DPLL's parent clock, it will enter bypass;
429 * otherwise, it will enter lock. This code will wait for the DPLL to
430 * indicate readiness before returning, unless the DPLL takes too long
431 * to enter the target state. Intended to be used as the struct clk's
432 * enable function. If DPLL3 was passed in, or the DPLL does not
433 * support low-power stop, or if the DPLL took too long to enter
434 * bypass or lock, return -EINVAL; otherwise, return 0.
435 */
omap3_noncore_dpll_enable(struct clk_hw * hw)436 int omap3_noncore_dpll_enable(struct clk_hw *hw)
437 {
438 struct clk_hw_omap *clk = to_clk_hw_omap(hw);
439 int r;
440 struct dpll_data *dd;
441 struct clk_hw *parent;
442
443 dd = clk->dpll_data;
444 if (!dd)
445 return -EINVAL;
446
447 if (clk->clkdm) {
448 r = ti_clk_ll_ops->clkdm_clk_enable(clk->clkdm, hw->clk);
449 if (r) {
450 WARN(1,
451 "%s: could not enable %s's clockdomain %s: %d\n",
452 __func__, clk_hw_get_name(hw),
453 clk->clkdm_name, r);
454 return r;
455 }
456 }
457
458 parent = clk_hw_get_parent(hw);
459
460 if (clk_hw_get_rate(hw) == clk_hw_get_rate(dd->clk_bypass)) {
461 WARN_ON(parent != dd->clk_bypass);
462 r = _omap3_noncore_dpll_bypass(clk);
463 } else {
464 WARN_ON(parent != dd->clk_ref);
465 r = _omap3_noncore_dpll_lock(clk);
466 }
467
468 return r;
469 }
470
471 /**
472 * omap3_noncore_dpll_disable - instruct a DPLL to enter low-power stop
473 * @clk: pointer to a DPLL struct clk
474 *
475 * Instructs a non-CORE DPLL to enter low-power stop. This function is
476 * intended for use in struct clkops. No return value.
477 */
omap3_noncore_dpll_disable(struct clk_hw * hw)478 void omap3_noncore_dpll_disable(struct clk_hw *hw)
479 {
480 struct clk_hw_omap *clk = to_clk_hw_omap(hw);
481
482 _omap3_noncore_dpll_stop(clk);
483 if (clk->clkdm)
484 ti_clk_ll_ops->clkdm_clk_disable(clk->clkdm, hw->clk);
485 }
486
487 /* Non-CORE DPLL rate set code */
488
489 /**
490 * omap3_noncore_dpll_determine_rate - determine rate for a DPLL
491 * @hw: pointer to the clock to determine rate for
492 * @req: target rate request
493 *
494 * Determines which DPLL mode to use for reaching a desired target rate.
495 * Checks whether the DPLL shall be in bypass or locked mode, and if
496 * locked, calculates the M,N values for the DPLL via round-rate.
497 * Returns a 0 on success, negative error value in failure.
498 */
omap3_noncore_dpll_determine_rate(struct clk_hw * hw,struct clk_rate_request * req)499 int omap3_noncore_dpll_determine_rate(struct clk_hw *hw,
500 struct clk_rate_request *req)
501 {
502 struct clk_hw_omap *clk = to_clk_hw_omap(hw);
503 struct dpll_data *dd;
504
505 if (!req->rate)
506 return -EINVAL;
507
508 dd = clk->dpll_data;
509 if (!dd)
510 return -EINVAL;
511
512 if (clk_hw_get_rate(dd->clk_bypass) == req->rate &&
513 (dd->modes & (1 << DPLL_LOW_POWER_BYPASS))) {
514 req->best_parent_hw = dd->clk_bypass;
515 } else {
516 req->rate = omap2_dpll_round_rate(hw, req->rate,
517 &req->best_parent_rate);
518 req->best_parent_hw = dd->clk_ref;
519 }
520
521 req->best_parent_rate = req->rate;
522
523 return 0;
524 }
525
526 /**
527 * omap3_noncore_dpll_set_parent - set parent for a DPLL clock
528 * @hw: pointer to the clock to set parent for
529 * @index: parent index to select
530 *
531 * Sets parent for a DPLL clock. This sets the DPLL into bypass or
532 * locked mode. Returns 0 with success, negative error value otherwise.
533 */
omap3_noncore_dpll_set_parent(struct clk_hw * hw,u8 index)534 int omap3_noncore_dpll_set_parent(struct clk_hw *hw, u8 index)
535 {
536 struct clk_hw_omap *clk = to_clk_hw_omap(hw);
537 int ret;
538
539 if (!hw)
540 return -EINVAL;
541
542 if (index)
543 ret = _omap3_noncore_dpll_bypass(clk);
544 else
545 ret = _omap3_noncore_dpll_lock(clk);
546
547 return ret;
548 }
549
550 /**
551 * omap3_noncore_dpll_set_rate - set rate for a DPLL clock
552 * @hw: pointer to the clock to set parent for
553 * @rate: target rate for the clock
554 * @parent_rate: rate of the parent clock
555 *
556 * Sets rate for a DPLL clock. First checks if the clock parent is
557 * reference clock (in bypass mode, the rate of the clock can't be
558 * changed) and proceeds with the rate change operation. Returns 0
559 * with success, negative error value otherwise.
560 */
omap3_noncore_dpll_set_rate(struct clk_hw * hw,unsigned long rate,unsigned long parent_rate)561 int omap3_noncore_dpll_set_rate(struct clk_hw *hw, unsigned long rate,
562 unsigned long parent_rate)
563 {
564 struct clk_hw_omap *clk = to_clk_hw_omap(hw);
565 struct dpll_data *dd;
566 u16 freqsel = 0;
567 int ret;
568
569 if (!hw || !rate)
570 return -EINVAL;
571
572 dd = clk->dpll_data;
573 if (!dd)
574 return -EINVAL;
575
576 if (clk_hw_get_parent(hw) != dd->clk_ref)
577 return -EINVAL;
578
579 if (dd->last_rounded_rate == 0)
580 return -EINVAL;
581
582 /* Freqsel is available only on OMAP343X devices */
583 if (ti_clk_get_features()->flags & TI_CLK_DPLL_HAS_FREQSEL) {
584 freqsel = _omap3_dpll_compute_freqsel(clk, dd->last_rounded_n);
585 WARN_ON(!freqsel);
586 }
587
588 pr_debug("%s: %s: set rate: locking rate to %lu.\n", __func__,
589 clk_hw_get_name(hw), rate);
590
591 ret = omap3_noncore_dpll_program(clk, freqsel);
592
593 return ret;
594 }
595
596 /**
597 * omap3_noncore_dpll_set_rate_and_parent - set rate and parent for a DPLL clock
598 * @hw: pointer to the clock to set rate and parent for
599 * @rate: target rate for the DPLL
600 * @parent_rate: clock rate of the DPLL parent
601 * @index: new parent index for the DPLL, 0 - reference, 1 - bypass
602 *
603 * Sets rate and parent for a DPLL clock. If new parent is the bypass
604 * clock, only selects the parent. Otherwise proceeds with a rate
605 * change, as this will effectively also change the parent as the
606 * DPLL is put into locked mode. Returns 0 with success, negative error
607 * value otherwise.
608 */
omap3_noncore_dpll_set_rate_and_parent(struct clk_hw * hw,unsigned long rate,unsigned long parent_rate,u8 index)609 int omap3_noncore_dpll_set_rate_and_parent(struct clk_hw *hw,
610 unsigned long rate,
611 unsigned long parent_rate,
612 u8 index)
613 {
614 int ret;
615
616 if (!hw || !rate)
617 return -EINVAL;
618
619 /*
620 * clk-ref at index[0], in which case we only need to set rate,
621 * the parent will be changed automatically with the lock sequence.
622 * With clk-bypass case we only need to change parent.
623 */
624 if (index)
625 ret = omap3_noncore_dpll_set_parent(hw, index);
626 else
627 ret = omap3_noncore_dpll_set_rate(hw, rate, parent_rate);
628
629 return ret;
630 }
631
632 /* DPLL autoidle read/set code */
633
634 /**
635 * omap3_dpll_autoidle_read - read a DPLL's autoidle bits
636 * @clk: struct clk * of the DPLL to read
637 *
638 * Return the DPLL's autoidle bits, shifted down to bit 0. Returns
639 * -EINVAL if passed a null pointer or if the struct clk does not
640 * appear to refer to a DPLL.
641 */
omap3_dpll_autoidle_read(struct clk_hw_omap * clk)642 static u32 omap3_dpll_autoidle_read(struct clk_hw_omap *clk)
643 {
644 const struct dpll_data *dd;
645 u32 v;
646
647 if (!clk || !clk->dpll_data)
648 return -EINVAL;
649
650 dd = clk->dpll_data;
651
652 if (!dd->autoidle_mask)
653 return -EINVAL;
654
655 v = ti_clk_ll_ops->clk_readl(&dd->autoidle_reg);
656 v &= dd->autoidle_mask;
657 v >>= __ffs(dd->autoidle_mask);
658
659 return v;
660 }
661
662 /**
663 * omap3_dpll_allow_idle - enable DPLL autoidle bits
664 * @clk: struct clk * of the DPLL to operate on
665 *
666 * Enable DPLL automatic idle control. This automatic idle mode
667 * switching takes effect only when the DPLL is locked, at least on
668 * OMAP3430. The DPLL will enter low-power stop when its downstream
669 * clocks are gated. No return value.
670 */
omap3_dpll_allow_idle(struct clk_hw_omap * clk)671 static void omap3_dpll_allow_idle(struct clk_hw_omap *clk)
672 {
673 const struct dpll_data *dd;
674 u32 v;
675
676 if (!clk || !clk->dpll_data)
677 return;
678
679 dd = clk->dpll_data;
680
681 if (!dd->autoidle_mask)
682 return;
683
684 /*
685 * REVISIT: CORE DPLL can optionally enter low-power bypass
686 * by writing 0x5 instead of 0x1. Add some mechanism to
687 * optionally enter this mode.
688 */
689 v = ti_clk_ll_ops->clk_readl(&dd->autoidle_reg);
690 v &= ~dd->autoidle_mask;
691 v |= DPLL_AUTOIDLE_LOW_POWER_STOP << __ffs(dd->autoidle_mask);
692 ti_clk_ll_ops->clk_writel(v, &dd->autoidle_reg);
693 }
694
695 /**
696 * omap3_dpll_deny_idle - prevent DPLL from automatically idling
697 * @clk: struct clk * of the DPLL to operate on
698 *
699 * Disable DPLL automatic idle control. No return value.
700 */
omap3_dpll_deny_idle(struct clk_hw_omap * clk)701 static void omap3_dpll_deny_idle(struct clk_hw_omap *clk)
702 {
703 const struct dpll_data *dd;
704 u32 v;
705
706 if (!clk || !clk->dpll_data)
707 return;
708
709 dd = clk->dpll_data;
710
711 if (!dd->autoidle_mask)
712 return;
713
714 v = ti_clk_ll_ops->clk_readl(&dd->autoidle_reg);
715 v &= ~dd->autoidle_mask;
716 v |= DPLL_AUTOIDLE_DISABLE << __ffs(dd->autoidle_mask);
717 ti_clk_ll_ops->clk_writel(v, &dd->autoidle_reg);
718 }
719
720 /* Clock control for DPLL outputs */
721
722 /* Find the parent DPLL for the given clkoutx2 clock */
omap3_find_clkoutx2_dpll(struct clk_hw * hw)723 static struct clk_hw_omap *omap3_find_clkoutx2_dpll(struct clk_hw *hw)
724 {
725 struct clk_hw_omap *pclk = NULL;
726
727 /* Walk up the parents of clk, looking for a DPLL */
728 do {
729 do {
730 hw = clk_hw_get_parent(hw);
731 } while (hw && (!omap2_clk_is_hw_omap(hw)));
732 if (!hw)
733 break;
734 pclk = to_clk_hw_omap(hw);
735 } while (pclk && !pclk->dpll_data);
736
737 /* clk does not have a DPLL as a parent? error in the clock data */
738 if (!pclk) {
739 WARN_ON(1);
740 return NULL;
741 }
742
743 return pclk;
744 }
745
746 /**
747 * omap3_clkoutx2_recalc - recalculate DPLL X2 output virtual clock rate
748 * @clk: DPLL output struct clk
749 *
750 * Using parent clock DPLL data, look up DPLL state. If locked, set our
751 * rate to the dpll_clk * 2; otherwise, just use dpll_clk.
752 */
omap3_clkoutx2_recalc(struct clk_hw * hw,unsigned long parent_rate)753 unsigned long omap3_clkoutx2_recalc(struct clk_hw *hw,
754 unsigned long parent_rate)
755 {
756 const struct dpll_data *dd;
757 unsigned long rate;
758 u32 v;
759 struct clk_hw_omap *pclk = NULL;
760
761 if (!parent_rate)
762 return 0;
763
764 pclk = omap3_find_clkoutx2_dpll(hw);
765
766 if (!pclk)
767 return 0;
768
769 dd = pclk->dpll_data;
770
771 WARN_ON(!dd->enable_mask);
772
773 v = ti_clk_ll_ops->clk_readl(&dd->control_reg) & dd->enable_mask;
774 v >>= __ffs(dd->enable_mask);
775 if ((v != OMAP3XXX_EN_DPLL_LOCKED) || (dd->flags & DPLL_J_TYPE))
776 rate = parent_rate;
777 else
778 rate = parent_rate * 2;
779 return rate;
780 }
781
782 /**
783 * omap3_core_dpll_save_context - Save the m and n values of the divider
784 * @hw: pointer struct clk_hw
785 *
786 * Before the dpll registers are lost save the last rounded rate m and n
787 * and the enable mask.
788 */
omap3_core_dpll_save_context(struct clk_hw * hw)789 int omap3_core_dpll_save_context(struct clk_hw *hw)
790 {
791 struct clk_hw_omap *clk = to_clk_hw_omap(hw);
792 struct dpll_data *dd;
793 u32 v;
794
795 dd = clk->dpll_data;
796
797 v = ti_clk_ll_ops->clk_readl(&dd->control_reg);
798 clk->context = (v & dd->enable_mask) >> __ffs(dd->enable_mask);
799
800 if (clk->context == DPLL_LOCKED) {
801 v = ti_clk_ll_ops->clk_readl(&dd->mult_div1_reg);
802 dd->last_rounded_m = (v & dd->mult_mask) >>
803 __ffs(dd->mult_mask);
804 dd->last_rounded_n = ((v & dd->div1_mask) >>
805 __ffs(dd->div1_mask)) + 1;
806 }
807
808 return 0;
809 }
810
811 /**
812 * omap3_core_dpll_restore_context - restore the m and n values of the divider
813 * @hw: pointer struct clk_hw
814 *
815 * Restore the last rounded rate m and n
816 * and the enable mask.
817 */
omap3_core_dpll_restore_context(struct clk_hw * hw)818 void omap3_core_dpll_restore_context(struct clk_hw *hw)
819 {
820 struct clk_hw_omap *clk = to_clk_hw_omap(hw);
821 const struct dpll_data *dd;
822 u32 v;
823
824 dd = clk->dpll_data;
825
826 if (clk->context == DPLL_LOCKED) {
827 _omap3_dpll_write_clken(clk, 0x4);
828 _omap3_wait_dpll_status(clk, 0);
829
830 v = ti_clk_ll_ops->clk_readl(&dd->mult_div1_reg);
831 v &= ~(dd->mult_mask | dd->div1_mask);
832 v |= dd->last_rounded_m << __ffs(dd->mult_mask);
833 v |= (dd->last_rounded_n - 1) << __ffs(dd->div1_mask);
834 ti_clk_ll_ops->clk_writel(v, &dd->mult_div1_reg);
835
836 _omap3_dpll_write_clken(clk, DPLL_LOCKED);
837 _omap3_wait_dpll_status(clk, 1);
838 } else {
839 _omap3_dpll_write_clken(clk, clk->context);
840 }
841 }
842
843 /**
844 * omap3_non_core_dpll_save_context - Save the m and n values of the divider
845 * @hw: pointer struct clk_hw
846 *
847 * Before the dpll registers are lost save the last rounded rate m and n
848 * and the enable mask.
849 */
omap3_noncore_dpll_save_context(struct clk_hw * hw)850 int omap3_noncore_dpll_save_context(struct clk_hw *hw)
851 {
852 struct clk_hw_omap *clk = to_clk_hw_omap(hw);
853 struct dpll_data *dd;
854 u32 v;
855
856 dd = clk->dpll_data;
857
858 v = ti_clk_ll_ops->clk_readl(&dd->control_reg);
859 clk->context = (v & dd->enable_mask) >> __ffs(dd->enable_mask);
860
861 if (clk->context == DPLL_LOCKED) {
862 v = ti_clk_ll_ops->clk_readl(&dd->mult_div1_reg);
863 dd->last_rounded_m = (v & dd->mult_mask) >>
864 __ffs(dd->mult_mask);
865 dd->last_rounded_n = ((v & dd->div1_mask) >>
866 __ffs(dd->div1_mask)) + 1;
867 }
868
869 return 0;
870 }
871
872 /**
873 * omap3_core_dpll_restore_context - restore the m and n values of the divider
874 * @hw: pointer struct clk_hw
875 *
876 * Restore the last rounded rate m and n
877 * and the enable mask.
878 */
omap3_noncore_dpll_restore_context(struct clk_hw * hw)879 void omap3_noncore_dpll_restore_context(struct clk_hw *hw)
880 {
881 struct clk_hw_omap *clk = to_clk_hw_omap(hw);
882 const struct dpll_data *dd;
883 u32 ctrl, mult_div1;
884
885 dd = clk->dpll_data;
886
887 ctrl = ti_clk_ll_ops->clk_readl(&dd->control_reg);
888 mult_div1 = ti_clk_ll_ops->clk_readl(&dd->mult_div1_reg);
889
890 if (clk->context == ((ctrl & dd->enable_mask) >>
891 __ffs(dd->enable_mask)) &&
892 dd->last_rounded_m == ((mult_div1 & dd->mult_mask) >>
893 __ffs(dd->mult_mask)) &&
894 dd->last_rounded_n == ((mult_div1 & dd->div1_mask) >>
895 __ffs(dd->div1_mask)) + 1) {
896 /* nothing to be done */
897 return;
898 }
899
900 if (clk->context == DPLL_LOCKED)
901 omap3_noncore_dpll_program(clk, 0);
902 else
903 _omap3_dpll_write_clken(clk, clk->context);
904 }
905
906 /* OMAP3/4 non-CORE DPLL clkops */
907 const struct clk_hw_omap_ops clkhwops_omap3_dpll = {
908 .allow_idle = omap3_dpll_allow_idle,
909 .deny_idle = omap3_dpll_deny_idle,
910 };
911
912 /**
913 * omap3_dpll4_set_rate - set rate for omap3 per-dpll
914 * @hw: clock to change
915 * @rate: target rate for clock
916 * @parent_rate: rate of the parent clock
917 *
918 * Check if the current SoC supports the per-dpll reprogram operation
919 * or not, and then do the rate change if supported. Returns -EINVAL
920 * if not supported, 0 for success, and potential error codes from the
921 * clock rate change.
922 */
omap3_dpll4_set_rate(struct clk_hw * hw,unsigned long rate,unsigned long parent_rate)923 int omap3_dpll4_set_rate(struct clk_hw *hw, unsigned long rate,
924 unsigned long parent_rate)
925 {
926 /*
927 * According to the 12-5 CDP code from TI, "Limitation 2.5"
928 * on 3430ES1 prevents us from changing DPLL multipliers or dividers
929 * on DPLL4.
930 */
931 if (ti_clk_get_features()->flags & TI_CLK_DPLL4_DENY_REPROGRAM) {
932 pr_err("clock: DPLL4 cannot change rate due to silicon 'Limitation 2.5' on 3430ES1.\n");
933 return -EINVAL;
934 }
935
936 return omap3_noncore_dpll_set_rate(hw, rate, parent_rate);
937 }
938
939 /**
940 * omap3_dpll4_set_rate_and_parent - set rate and parent for omap3 per-dpll
941 * @hw: clock to change
942 * @rate: target rate for clock
943 * @parent_rate: rate of the parent clock
944 * @index: parent index, 0 - reference clock, 1 - bypass clock
945 *
946 * Check if the current SoC support the per-dpll reprogram operation
947 * or not, and then do the rate + parent change if supported. Returns
948 * -EINVAL if not supported, 0 for success, and potential error codes
949 * from the clock rate change.
950 */
omap3_dpll4_set_rate_and_parent(struct clk_hw * hw,unsigned long rate,unsigned long parent_rate,u8 index)951 int omap3_dpll4_set_rate_and_parent(struct clk_hw *hw, unsigned long rate,
952 unsigned long parent_rate, u8 index)
953 {
954 if (ti_clk_get_features()->flags & TI_CLK_DPLL4_DENY_REPROGRAM) {
955 pr_err("clock: DPLL4 cannot change rate due to silicon 'Limitation 2.5' on 3430ES1.\n");
956 return -EINVAL;
957 }
958
959 return omap3_noncore_dpll_set_rate_and_parent(hw, rate, parent_rate,
960 index);
961 }
962
963 /* Apply DM3730 errata sprz319 advisory 2.1. */
omap3_dpll5_apply_errata(struct clk_hw * hw,unsigned long parent_rate)964 static bool omap3_dpll5_apply_errata(struct clk_hw *hw,
965 unsigned long parent_rate)
966 {
967 struct omap3_dpll5_settings {
968 unsigned int rate, m, n;
969 };
970
971 static const struct omap3_dpll5_settings precomputed[] = {
972 /*
973 * From DM3730 errata advisory 2.1, table 35 and 36.
974 * The N value is increased by 1 compared to the tables as the
975 * errata lists register values while last_rounded_field is the
976 * real divider value.
977 */
978 { 12000000, 80, 0 + 1 },
979 { 13000000, 443, 5 + 1 },
980 { 19200000, 50, 0 + 1 },
981 { 26000000, 443, 11 + 1 },
982 { 38400000, 25, 0 + 1 }
983 };
984
985 const struct omap3_dpll5_settings *d;
986 struct clk_hw_omap *clk = to_clk_hw_omap(hw);
987 struct dpll_data *dd;
988 unsigned int i;
989
990 for (i = 0; i < ARRAY_SIZE(precomputed); ++i) {
991 if (parent_rate == precomputed[i].rate)
992 break;
993 }
994
995 if (i == ARRAY_SIZE(precomputed))
996 return false;
997
998 d = &precomputed[i];
999
1000 /* Update the M, N and rounded rate values and program the DPLL. */
1001 dd = clk->dpll_data;
1002 dd->last_rounded_m = d->m;
1003 dd->last_rounded_n = d->n;
1004 dd->last_rounded_rate = div_u64((u64)parent_rate * d->m, d->n);
1005 omap3_noncore_dpll_program(clk, 0);
1006
1007 return true;
1008 }
1009
1010 /**
1011 * omap3_dpll5_set_rate - set rate for omap3 dpll5
1012 * @hw: clock to change
1013 * @rate: target rate for clock
1014 * @parent_rate: rate of the parent clock
1015 *
1016 * Set rate for the DPLL5 clock. Apply the sprz319 advisory 2.1 on OMAP36xx if
1017 * the DPLL is used for USB host (detected through the requested rate).
1018 */
omap3_dpll5_set_rate(struct clk_hw * hw,unsigned long rate,unsigned long parent_rate)1019 int omap3_dpll5_set_rate(struct clk_hw *hw, unsigned long rate,
1020 unsigned long parent_rate)
1021 {
1022 if (rate == OMAP3_DPLL5_FREQ_FOR_USBHOST * 8) {
1023 if (omap3_dpll5_apply_errata(hw, parent_rate))
1024 return 0;
1025 }
1026
1027 return omap3_noncore_dpll_set_rate(hw, rate, parent_rate);
1028 }
1029