1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * PLL clock driver for TI Davinci SoCs
4 *
5 * Copyright (C) 2018 David Lechner <david@lechnology.com>
6 *
7 * Based on arch/arm/mach-davinci/clock.c
8 * Copyright (C) 2006-2007 Texas Instruments.
9 * Copyright (C) 2008-2009 Deep Root Systems, LLC
10 */
11
12 #include <linux/clk-provider.h>
13 #include <linux/clk.h>
14 #include <linux/clk/davinci.h>
15 #include <linux/delay.h>
16 #include <linux/err.h>
17 #include <linux/io.h>
18 #include <linux/kernel.h>
19 #include <linux/mfd/syscon.h>
20 #include <linux/notifier.h>
21 #include <linux/of_address.h>
22 #include <linux/of_device.h>
23 #include <linux/of.h>
24 #include <linux/platform_data/clk-davinci-pll.h>
25 #include <linux/platform_device.h>
26 #include <linux/regmap.h>
27 #include <linux/slab.h>
28 #include <linux/types.h>
29
30 #include "pll.h"
31
32 #define MAX_NAME_SIZE 20
33 #define OSCIN_CLK_NAME "oscin"
34
35 #define REVID 0x000
36 #define PLLCTL 0x100
37 #define OCSEL 0x104
38 #define PLLSECCTL 0x108
39 #define PLLM 0x110
40 #define PREDIV 0x114
41 #define PLLDIV1 0x118
42 #define PLLDIV2 0x11c
43 #define PLLDIV3 0x120
44 #define OSCDIV 0x124
45 #define POSTDIV 0x128
46 #define BPDIV 0x12c
47 #define PLLCMD 0x138
48 #define PLLSTAT 0x13c
49 #define ALNCTL 0x140
50 #define DCHANGE 0x144
51 #define CKEN 0x148
52 #define CKSTAT 0x14c
53 #define SYSTAT 0x150
54 #define PLLDIV4 0x160
55 #define PLLDIV5 0x164
56 #define PLLDIV6 0x168
57 #define PLLDIV7 0x16c
58 #define PLLDIV8 0x170
59 #define PLLDIV9 0x174
60
61 #define PLLCTL_PLLEN BIT(0)
62 #define PLLCTL_PLLPWRDN BIT(1)
63 #define PLLCTL_PLLRST BIT(3)
64 #define PLLCTL_PLLDIS BIT(4)
65 #define PLLCTL_PLLENSRC BIT(5)
66 #define PLLCTL_CLKMODE BIT(8)
67
68 /* shared by most *DIV registers */
69 #define DIV_RATIO_SHIFT 0
70 #define DIV_RATIO_WIDTH 5
71 #define DIV_ENABLE_SHIFT 15
72
73 #define PLLCMD_GOSET BIT(0)
74 #define PLLSTAT_GOSTAT BIT(0)
75
76 #define CKEN_OBSCLK_SHIFT 1
77 #define CKEN_AUXEN_SHIFT 0
78
79 /*
80 * OMAP-L138 system reference guide recommends a wait for 4 OSCIN/CLKIN
81 * cycles to ensure that the PLLC has switched to bypass mode. Delay of 1us
82 * ensures we are good for all > 4MHz OSCIN/CLKIN inputs. Typically the input
83 * is ~25MHz. Units are micro seconds.
84 */
85 #define PLL_BYPASS_TIME 1
86
87 /* From OMAP-L138 datasheet table 6-4. Units are micro seconds */
88 #define PLL_RESET_TIME 1
89
90 /*
91 * From OMAP-L138 datasheet table 6-4; assuming prediv = 1, sqrt(pllm) = 4
92 * Units are micro seconds.
93 */
94 #define PLL_LOCK_TIME 20
95
96 /**
97 * struct davinci_pll_clk - Main PLL clock (aka PLLOUT)
98 * @hw: clk_hw for the pll
99 * @base: Base memory address
100 * @pllm_min: The minimum allowable PLLM[PLLM] value
101 * @pllm_max: The maximum allowable PLLM[PLLM] value
102 * @pllm_mask: Bitmask for PLLM[PLLM] value
103 */
104 struct davinci_pll_clk {
105 struct clk_hw hw;
106 void __iomem *base;
107 u32 pllm_min;
108 u32 pllm_max;
109 u32 pllm_mask;
110 };
111
112 #define to_davinci_pll_clk(_hw) \
113 container_of((_hw), struct davinci_pll_clk, hw)
114
davinci_pll_recalc_rate(struct clk_hw * hw,unsigned long parent_rate)115 static unsigned long davinci_pll_recalc_rate(struct clk_hw *hw,
116 unsigned long parent_rate)
117 {
118 struct davinci_pll_clk *pll = to_davinci_pll_clk(hw);
119 unsigned long rate = parent_rate;
120 u32 mult;
121
122 mult = readl(pll->base + PLLM) & pll->pllm_mask;
123 rate *= mult + 1;
124
125 return rate;
126 }
127
davinci_pll_determine_rate(struct clk_hw * hw,struct clk_rate_request * req)128 static int davinci_pll_determine_rate(struct clk_hw *hw,
129 struct clk_rate_request *req)
130 {
131 struct davinci_pll_clk *pll = to_davinci_pll_clk(hw);
132 struct clk_hw *parent = req->best_parent_hw;
133 unsigned long parent_rate = req->best_parent_rate;
134 unsigned long rate = req->rate;
135 unsigned long best_rate, r;
136 u32 mult;
137
138 /* there is a limited range of valid outputs (see datasheet) */
139 if (rate < req->min_rate)
140 return -EINVAL;
141
142 rate = min(rate, req->max_rate);
143 mult = rate / parent_rate;
144 best_rate = parent_rate * mult;
145
146 /* easy case when there is no PREDIV */
147 if (!(clk_hw_get_flags(hw) & CLK_SET_RATE_PARENT)) {
148 if (best_rate < req->min_rate)
149 return -EINVAL;
150
151 if (mult < pll->pllm_min || mult > pll->pllm_max)
152 return -EINVAL;
153
154 req->rate = best_rate;
155
156 return 0;
157 }
158
159 /* see if the PREDIV clock can help us */
160 best_rate = 0;
161
162 for (mult = pll->pllm_min; mult <= pll->pllm_max; mult++) {
163 parent_rate = clk_hw_round_rate(parent, rate / mult);
164 r = parent_rate * mult;
165 if (r < req->min_rate)
166 continue;
167 if (r > rate || r > req->max_rate)
168 break;
169 if (r > best_rate) {
170 best_rate = r;
171 req->rate = best_rate;
172 req->best_parent_rate = parent_rate;
173 if (best_rate == rate)
174 break;
175 }
176 }
177
178 return 0;
179 }
180
davinci_pll_set_rate(struct clk_hw * hw,unsigned long rate,unsigned long parent_rate)181 static int davinci_pll_set_rate(struct clk_hw *hw, unsigned long rate,
182 unsigned long parent_rate)
183 {
184 struct davinci_pll_clk *pll = to_davinci_pll_clk(hw);
185 u32 mult;
186
187 mult = rate / parent_rate;
188 writel(mult - 1, pll->base + PLLM);
189
190 return 0;
191 }
192
193 #ifdef CONFIG_DEBUG_FS
194 static void davinci_pll_debug_init(struct clk_hw *hw, struct dentry *dentry);
195 #else
196 #define davinci_pll_debug_init NULL
197 #endif
198
199 static const struct clk_ops davinci_pll_ops = {
200 .recalc_rate = davinci_pll_recalc_rate,
201 .determine_rate = davinci_pll_determine_rate,
202 .set_rate = davinci_pll_set_rate,
203 .debug_init = davinci_pll_debug_init,
204 };
205
206 /* PLLM works differently on DM365 */
dm365_pll_recalc_rate(struct clk_hw * hw,unsigned long parent_rate)207 static unsigned long dm365_pll_recalc_rate(struct clk_hw *hw,
208 unsigned long parent_rate)
209 {
210 struct davinci_pll_clk *pll = to_davinci_pll_clk(hw);
211 unsigned long rate = parent_rate;
212 u32 mult;
213
214 mult = readl(pll->base + PLLM) & pll->pllm_mask;
215 rate *= mult * 2;
216
217 return rate;
218 }
219
220 static const struct clk_ops dm365_pll_ops = {
221 .recalc_rate = dm365_pll_recalc_rate,
222 .debug_init = davinci_pll_debug_init,
223 };
224
225 /**
226 * davinci_pll_div_register - common *DIV clock implementation
227 * @dev: The PLL platform device or NULL
228 * @name: the clock name
229 * @parent_name: the parent clock name
230 * @reg: the *DIV register
231 * @fixed: if true, the divider is a fixed value
232 * @flags: bitmap of CLK_* flags from clock-provider.h
233 */
davinci_pll_div_register(struct device * dev,const char * name,const char * parent_name,void __iomem * reg,bool fixed,u32 flags)234 static struct clk *davinci_pll_div_register(struct device *dev,
235 const char *name,
236 const char *parent_name,
237 void __iomem *reg,
238 bool fixed, u32 flags)
239 {
240 const char * const *parent_names = parent_name ? &parent_name : NULL;
241 int num_parents = parent_name ? 1 : 0;
242 const struct clk_ops *divider_ops = &clk_divider_ops;
243 struct clk_gate *gate;
244 struct clk_divider *divider;
245 struct clk *clk;
246 int ret;
247
248 gate = kzalloc(sizeof(*gate), GFP_KERNEL);
249 if (!gate)
250 return ERR_PTR(-ENOMEM);
251
252 gate->reg = reg;
253 gate->bit_idx = DIV_ENABLE_SHIFT;
254
255 divider = kzalloc(sizeof(*divider), GFP_KERNEL);
256 if (!divider) {
257 ret = -ENOMEM;
258 goto err_free_gate;
259 }
260
261 divider->reg = reg;
262 divider->shift = DIV_RATIO_SHIFT;
263 divider->width = DIV_RATIO_WIDTH;
264
265 if (fixed) {
266 divider->flags |= CLK_DIVIDER_READ_ONLY;
267 divider_ops = &clk_divider_ro_ops;
268 }
269
270 clk = clk_register_composite(dev, name, parent_names, num_parents,
271 NULL, NULL, ÷r->hw, divider_ops,
272 &gate->hw, &clk_gate_ops, flags);
273 if (IS_ERR(clk)) {
274 ret = PTR_ERR(clk);
275 goto err_free_divider;
276 }
277
278 return clk;
279
280 err_free_divider:
281 kfree(divider);
282 err_free_gate:
283 kfree(gate);
284
285 return ERR_PTR(ret);
286 }
287
288 struct davinci_pllen_clk {
289 struct clk_hw hw;
290 void __iomem *base;
291 };
292
293 #define to_davinci_pllen_clk(_hw) \
294 container_of((_hw), struct davinci_pllen_clk, hw)
295
296 static const struct clk_ops davinci_pllen_ops = {
297 /* this clocks just uses the clock notification feature */
298 };
299
300 /*
301 * The PLL has to be switched into bypass mode while we are chaning the rate,
302 * so we do that on the PLLEN clock since it is the end of the line. This will
303 * switch to bypass before any of the parent clocks (PREDIV, PLL, POSTDIV) are
304 * changed and will switch back to the PLL after the changes have been made.
305 */
davinci_pllen_rate_change(struct notifier_block * nb,unsigned long flags,void * data)306 static int davinci_pllen_rate_change(struct notifier_block *nb,
307 unsigned long flags, void *data)
308 {
309 struct clk_notifier_data *cnd = data;
310 struct clk_hw *hw = __clk_get_hw(cnd->clk);
311 struct davinci_pllen_clk *pll = to_davinci_pllen_clk(hw);
312 u32 ctrl;
313
314 ctrl = readl(pll->base + PLLCTL);
315
316 if (flags == PRE_RATE_CHANGE) {
317 /* Switch the PLL to bypass mode */
318 ctrl &= ~(PLLCTL_PLLENSRC | PLLCTL_PLLEN);
319 writel(ctrl, pll->base + PLLCTL);
320
321 udelay(PLL_BYPASS_TIME);
322
323 /* Reset and enable PLL */
324 ctrl &= ~(PLLCTL_PLLRST | PLLCTL_PLLDIS);
325 writel(ctrl, pll->base + PLLCTL);
326 } else {
327 udelay(PLL_RESET_TIME);
328
329 /* Bring PLL out of reset */
330 ctrl |= PLLCTL_PLLRST;
331 writel(ctrl, pll->base + PLLCTL);
332
333 udelay(PLL_LOCK_TIME);
334
335 /* Remove PLL from bypass mode */
336 ctrl |= PLLCTL_PLLEN;
337 writel(ctrl, pll->base + PLLCTL);
338 }
339
340 return NOTIFY_OK;
341 }
342
343 static struct notifier_block davinci_pllen_notifier = {
344 .notifier_call = davinci_pllen_rate_change,
345 };
346
347 /**
348 * davinci_pll_clk_register - Register a PLL clock
349 * @dev: The PLL platform device or NULL
350 * @info: The device-specific clock info
351 * @parent_name: The parent clock name
352 * @base: The PLL's memory region
353 * @cfgchip: CFGCHIP syscon regmap for info->unlock_reg or NULL
354 *
355 * This creates a series of clocks that represent the PLL.
356 *
357 * OSCIN > [PREDIV >] PLL > [POSTDIV >] PLLEN
358 *
359 * - OSCIN is the parent clock (on secondary PLL, may come from primary PLL)
360 * - PREDIV and POSTDIV are optional (depends on the PLL controller)
361 * - PLL is the PLL output (aka PLLOUT)
362 * - PLLEN is the bypass multiplexer
363 *
364 * Returns: The PLLOUT clock or a negative error code.
365 */
davinci_pll_clk_register(struct device * dev,const struct davinci_pll_clk_info * info,const char * parent_name,void __iomem * base,struct regmap * cfgchip)366 struct clk *davinci_pll_clk_register(struct device *dev,
367 const struct davinci_pll_clk_info *info,
368 const char *parent_name,
369 void __iomem *base,
370 struct regmap *cfgchip)
371 {
372 char prediv_name[MAX_NAME_SIZE];
373 char pllout_name[MAX_NAME_SIZE];
374 char postdiv_name[MAX_NAME_SIZE];
375 char pllen_name[MAX_NAME_SIZE];
376 struct clk_init_data init;
377 struct davinci_pll_clk *pllout;
378 struct davinci_pllen_clk *pllen;
379 struct clk *oscin_clk = NULL;
380 struct clk *prediv_clk = NULL;
381 struct clk *pllout_clk;
382 struct clk *postdiv_clk = NULL;
383 struct clk *pllen_clk;
384 int ret;
385
386 if (info->flags & PLL_HAS_CLKMODE) {
387 /*
388 * If a PLL has PLLCTL[CLKMODE], then it is the primary PLL.
389 * We register a clock named "oscin" that serves as the internal
390 * "input clock" domain shared by both PLLs (if there are 2)
391 * and will be the parent clock to the AUXCLK, SYSCLKBP and
392 * OBSCLK domains. NB: The various TRMs use "OSCIN" to mean
393 * a number of different things. In this driver we use it to
394 * mean the signal after the PLLCTL[CLKMODE] switch.
395 */
396 oscin_clk = clk_register_fixed_factor(dev, OSCIN_CLK_NAME,
397 parent_name, 0, 1, 1);
398 if (IS_ERR(oscin_clk))
399 return oscin_clk;
400
401 parent_name = OSCIN_CLK_NAME;
402 }
403
404 if (info->flags & PLL_HAS_PREDIV) {
405 bool fixed = info->flags & PLL_PREDIV_FIXED_DIV;
406 u32 flags = 0;
407
408 snprintf(prediv_name, MAX_NAME_SIZE, "%s_prediv", info->name);
409
410 if (info->flags & PLL_PREDIV_ALWAYS_ENABLED)
411 flags |= CLK_IS_CRITICAL;
412
413 /* Some? DM355 chips don't correctly report the PREDIV value */
414 if (info->flags & PLL_PREDIV_FIXED8)
415 prediv_clk = clk_register_fixed_factor(dev, prediv_name,
416 parent_name, flags, 1, 8);
417 else
418 prediv_clk = davinci_pll_div_register(dev, prediv_name,
419 parent_name, base + PREDIV, fixed, flags);
420 if (IS_ERR(prediv_clk)) {
421 ret = PTR_ERR(prediv_clk);
422 goto err_unregister_oscin;
423 }
424
425 parent_name = prediv_name;
426 }
427
428 /* Unlock writing to PLL registers */
429 if (info->unlock_reg) {
430 if (IS_ERR_OR_NULL(cfgchip))
431 dev_warn(dev, "Failed to get CFGCHIP (%ld)\n",
432 PTR_ERR(cfgchip));
433 else
434 regmap_write_bits(cfgchip, info->unlock_reg,
435 info->unlock_mask, 0);
436 }
437
438 pllout = kzalloc(sizeof(*pllout), GFP_KERNEL);
439 if (!pllout) {
440 ret = -ENOMEM;
441 goto err_unregister_prediv;
442 }
443
444 snprintf(pllout_name, MAX_NAME_SIZE, "%s_pllout", info->name);
445
446 init.name = pllout_name;
447 if (info->flags & PLL_PLLM_2X)
448 init.ops = &dm365_pll_ops;
449 else
450 init.ops = &davinci_pll_ops;
451 init.parent_names = &parent_name;
452 init.num_parents = 1;
453 init.flags = 0;
454
455 if (info->flags & PLL_HAS_PREDIV)
456 init.flags |= CLK_SET_RATE_PARENT;
457
458 pllout->hw.init = &init;
459 pllout->base = base;
460 pllout->pllm_mask = info->pllm_mask;
461 pllout->pllm_min = info->pllm_min;
462 pllout->pllm_max = info->pllm_max;
463
464 pllout_clk = clk_register(dev, &pllout->hw);
465 if (IS_ERR(pllout_clk)) {
466 ret = PTR_ERR(pllout_clk);
467 goto err_free_pllout;
468 }
469
470 clk_hw_set_rate_range(&pllout->hw, info->pllout_min_rate,
471 info->pllout_max_rate);
472
473 parent_name = pllout_name;
474
475 if (info->flags & PLL_HAS_POSTDIV) {
476 bool fixed = info->flags & PLL_POSTDIV_FIXED_DIV;
477 u32 flags = CLK_SET_RATE_PARENT;
478
479 snprintf(postdiv_name, MAX_NAME_SIZE, "%s_postdiv", info->name);
480
481 if (info->flags & PLL_POSTDIV_ALWAYS_ENABLED)
482 flags |= CLK_IS_CRITICAL;
483
484 postdiv_clk = davinci_pll_div_register(dev, postdiv_name,
485 parent_name, base + POSTDIV, fixed, flags);
486 if (IS_ERR(postdiv_clk)) {
487 ret = PTR_ERR(postdiv_clk);
488 goto err_unregister_pllout;
489 }
490
491 parent_name = postdiv_name;
492 }
493
494 pllen = kzalloc(sizeof(*pllen), GFP_KERNEL);
495 if (!pllen) {
496 ret = -ENOMEM;
497 goto err_unregister_postdiv;
498 }
499
500 snprintf(pllen_name, MAX_NAME_SIZE, "%s_pllen", info->name);
501
502 init.name = pllen_name;
503 init.ops = &davinci_pllen_ops;
504 init.parent_names = &parent_name;
505 init.num_parents = 1;
506 init.flags = CLK_SET_RATE_PARENT;
507
508 pllen->hw.init = &init;
509 pllen->base = base;
510
511 pllen_clk = clk_register(dev, &pllen->hw);
512 if (IS_ERR(pllen_clk)) {
513 ret = PTR_ERR(pllen_clk);
514 goto err_free_pllen;
515 }
516
517 clk_notifier_register(pllen_clk, &davinci_pllen_notifier);
518
519 return pllout_clk;
520
521 err_free_pllen:
522 kfree(pllen);
523 err_unregister_postdiv:
524 clk_unregister(postdiv_clk);
525 err_unregister_pllout:
526 clk_unregister(pllout_clk);
527 err_free_pllout:
528 kfree(pllout);
529 err_unregister_prediv:
530 clk_unregister(prediv_clk);
531 err_unregister_oscin:
532 clk_unregister(oscin_clk);
533
534 return ERR_PTR(ret);
535 }
536
537 /**
538 * davinci_pll_auxclk_register - Register bypass clock (AUXCLK)
539 * @dev: The PLL platform device or NULL
540 * @name: The clock name
541 * @base: The PLL memory region
542 */
davinci_pll_auxclk_register(struct device * dev,const char * name,void __iomem * base)543 struct clk *davinci_pll_auxclk_register(struct device *dev,
544 const char *name,
545 void __iomem *base)
546 {
547 return clk_register_gate(dev, name, OSCIN_CLK_NAME, 0, base + CKEN,
548 CKEN_AUXEN_SHIFT, 0, NULL);
549 }
550
551 /**
552 * davinci_pll_sysclkbp_clk_register - Register bypass divider clock (SYSCLKBP)
553 * @dev: The PLL platform device or NULL
554 * @name: The clock name
555 * @base: The PLL memory region
556 */
davinci_pll_sysclkbp_clk_register(struct device * dev,const char * name,void __iomem * base)557 struct clk *davinci_pll_sysclkbp_clk_register(struct device *dev,
558 const char *name,
559 void __iomem *base)
560 {
561 return clk_register_divider(dev, name, OSCIN_CLK_NAME, 0, base + BPDIV,
562 DIV_RATIO_SHIFT, DIV_RATIO_WIDTH,
563 CLK_DIVIDER_READ_ONLY, NULL);
564 }
565
566 /**
567 * davinci_pll_obsclk_register - Register oscillator divider clock (OBSCLK)
568 * @dev: The PLL platform device or NULL
569 * @info: The clock info
570 * @base: The PLL memory region
571 */
572 struct clk *
davinci_pll_obsclk_register(struct device * dev,const struct davinci_pll_obsclk_info * info,void __iomem * base)573 davinci_pll_obsclk_register(struct device *dev,
574 const struct davinci_pll_obsclk_info *info,
575 void __iomem *base)
576 {
577 struct clk_mux *mux;
578 struct clk_gate *gate;
579 struct clk_divider *divider;
580 struct clk *clk;
581 u32 oscdiv;
582 int ret;
583
584 mux = kzalloc(sizeof(*mux), GFP_KERNEL);
585 if (!mux)
586 return ERR_PTR(-ENOMEM);
587
588 mux->reg = base + OCSEL;
589 mux->table = info->table;
590 mux->mask = info->ocsrc_mask;
591
592 gate = kzalloc(sizeof(*gate), GFP_KERNEL);
593 if (!gate) {
594 ret = -ENOMEM;
595 goto err_free_mux;
596 }
597
598 gate->reg = base + CKEN;
599 gate->bit_idx = CKEN_OBSCLK_SHIFT;
600
601 divider = kzalloc(sizeof(*divider), GFP_KERNEL);
602 if (!divider) {
603 ret = -ENOMEM;
604 goto err_free_gate;
605 }
606
607 divider->reg = base + OSCDIV;
608 divider->shift = DIV_RATIO_SHIFT;
609 divider->width = DIV_RATIO_WIDTH;
610
611 /* make sure divider is enabled just in case bootloader disabled it */
612 oscdiv = readl(base + OSCDIV);
613 oscdiv |= BIT(DIV_ENABLE_SHIFT);
614 writel(oscdiv, base + OSCDIV);
615
616 clk = clk_register_composite(dev, info->name, info->parent_names,
617 info->num_parents,
618 &mux->hw, &clk_mux_ops,
619 ÷r->hw, &clk_divider_ops,
620 &gate->hw, &clk_gate_ops, 0);
621
622 if (IS_ERR(clk)) {
623 ret = PTR_ERR(clk);
624 goto err_free_divider;
625 }
626
627 return clk;
628
629 err_free_divider:
630 kfree(divider);
631 err_free_gate:
632 kfree(gate);
633 err_free_mux:
634 kfree(mux);
635
636 return ERR_PTR(ret);
637 }
638
639 /* The PLL SYSCLKn clocks have a mechanism for synchronizing rate changes. */
davinci_pll_sysclk_rate_change(struct notifier_block * nb,unsigned long flags,void * data)640 static int davinci_pll_sysclk_rate_change(struct notifier_block *nb,
641 unsigned long flags, void *data)
642 {
643 struct clk_notifier_data *cnd = data;
644 struct clk_hw *hw = __clk_get_hw(clk_get_parent(cnd->clk));
645 struct davinci_pllen_clk *pll = to_davinci_pllen_clk(hw);
646 u32 pllcmd, pllstat;
647
648 switch (flags) {
649 case POST_RATE_CHANGE:
650 /* apply the changes */
651 pllcmd = readl(pll->base + PLLCMD);
652 pllcmd |= PLLCMD_GOSET;
653 writel(pllcmd, pll->base + PLLCMD);
654 fallthrough;
655 case PRE_RATE_CHANGE:
656 /* Wait until for outstanding changes to take effect */
657 do {
658 pllstat = readl(pll->base + PLLSTAT);
659 } while (pllstat & PLLSTAT_GOSTAT);
660 break;
661 }
662
663 return NOTIFY_OK;
664 }
665
666 static struct notifier_block davinci_pll_sysclk_notifier = {
667 .notifier_call = davinci_pll_sysclk_rate_change,
668 };
669
670 /**
671 * davinci_pll_sysclk_register - Register divider clocks (SYSCLKn)
672 * @dev: The PLL platform device or NULL
673 * @info: The clock info
674 * @base: The PLL memory region
675 */
676 struct clk *
davinci_pll_sysclk_register(struct device * dev,const struct davinci_pll_sysclk_info * info,void __iomem * base)677 davinci_pll_sysclk_register(struct device *dev,
678 const struct davinci_pll_sysclk_info *info,
679 void __iomem *base)
680 {
681 const struct clk_ops *divider_ops = &clk_divider_ops;
682 struct clk_gate *gate;
683 struct clk_divider *divider;
684 struct clk *clk;
685 u32 reg;
686 u32 flags = 0;
687 int ret;
688
689 /* PLLDIVn registers are not entirely consecutive */
690 if (info->id < 4)
691 reg = PLLDIV1 + 4 * (info->id - 1);
692 else
693 reg = PLLDIV4 + 4 * (info->id - 4);
694
695 gate = kzalloc(sizeof(*gate), GFP_KERNEL);
696 if (!gate)
697 return ERR_PTR(-ENOMEM);
698
699 gate->reg = base + reg;
700 gate->bit_idx = DIV_ENABLE_SHIFT;
701
702 divider = kzalloc(sizeof(*divider), GFP_KERNEL);
703 if (!divider) {
704 ret = -ENOMEM;
705 goto err_free_gate;
706 }
707
708 divider->reg = base + reg;
709 divider->shift = DIV_RATIO_SHIFT;
710 divider->width = info->ratio_width;
711 divider->flags = 0;
712
713 if (info->flags & SYSCLK_FIXED_DIV) {
714 divider->flags |= CLK_DIVIDER_READ_ONLY;
715 divider_ops = &clk_divider_ro_ops;
716 }
717
718 /* Only the ARM clock can change the parent PLL rate */
719 if (info->flags & SYSCLK_ARM_RATE)
720 flags |= CLK_SET_RATE_PARENT;
721
722 if (info->flags & SYSCLK_ALWAYS_ENABLED)
723 flags |= CLK_IS_CRITICAL;
724
725 clk = clk_register_composite(dev, info->name, &info->parent_name, 1,
726 NULL, NULL, ÷r->hw, divider_ops,
727 &gate->hw, &clk_gate_ops, flags);
728 if (IS_ERR(clk)) {
729 ret = PTR_ERR(clk);
730 goto err_free_divider;
731 }
732
733 clk_notifier_register(clk, &davinci_pll_sysclk_notifier);
734
735 return clk;
736
737 err_free_divider:
738 kfree(divider);
739 err_free_gate:
740 kfree(gate);
741
742 return ERR_PTR(ret);
743 }
744
of_davinci_pll_init(struct device * dev,struct device_node * node,const struct davinci_pll_clk_info * info,const struct davinci_pll_obsclk_info * obsclk_info,const struct davinci_pll_sysclk_info ** div_info,u8 max_sysclk_id,void __iomem * base,struct regmap * cfgchip)745 int of_davinci_pll_init(struct device *dev, struct device_node *node,
746 const struct davinci_pll_clk_info *info,
747 const struct davinci_pll_obsclk_info *obsclk_info,
748 const struct davinci_pll_sysclk_info **div_info,
749 u8 max_sysclk_id,
750 void __iomem *base,
751 struct regmap *cfgchip)
752 {
753 struct device_node *child;
754 const char *parent_name;
755 struct clk *clk;
756
757 if (info->flags & PLL_HAS_CLKMODE)
758 parent_name = of_clk_get_parent_name(node, 0);
759 else
760 parent_name = OSCIN_CLK_NAME;
761
762 clk = davinci_pll_clk_register(dev, info, parent_name, base, cfgchip);
763 if (IS_ERR(clk)) {
764 dev_err(dev, "failed to register %s\n", info->name);
765 return PTR_ERR(clk);
766 }
767
768 child = of_get_child_by_name(node, "pllout");
769 if (of_device_is_available(child))
770 of_clk_add_provider(child, of_clk_src_simple_get, clk);
771 of_node_put(child);
772
773 child = of_get_child_by_name(node, "sysclk");
774 if (of_device_is_available(child)) {
775 struct clk_onecell_data *clk_data;
776 struct clk **clks;
777 int n_clks = max_sysclk_id + 1;
778 int i;
779
780 clk_data = kzalloc(sizeof(*clk_data), GFP_KERNEL);
781 if (!clk_data) {
782 of_node_put(child);
783 return -ENOMEM;
784 }
785
786 clks = kmalloc_array(n_clks, sizeof(*clks), GFP_KERNEL);
787 if (!clks) {
788 kfree(clk_data);
789 of_node_put(child);
790 return -ENOMEM;
791 }
792
793 clk_data->clks = clks;
794 clk_data->clk_num = n_clks;
795
796 for (i = 0; i < n_clks; i++)
797 clks[i] = ERR_PTR(-ENOENT);
798
799 for (; *div_info; div_info++) {
800 clk = davinci_pll_sysclk_register(dev, *div_info, base);
801 if (IS_ERR(clk))
802 dev_warn(dev, "failed to register %s (%ld)\n",
803 (*div_info)->name, PTR_ERR(clk));
804 else
805 clks[(*div_info)->id] = clk;
806 }
807 of_clk_add_provider(child, of_clk_src_onecell_get, clk_data);
808 }
809 of_node_put(child);
810
811 child = of_get_child_by_name(node, "auxclk");
812 if (of_device_is_available(child)) {
813 char child_name[MAX_NAME_SIZE];
814
815 snprintf(child_name, MAX_NAME_SIZE, "%s_auxclk", info->name);
816
817 clk = davinci_pll_auxclk_register(dev, child_name, base);
818 if (IS_ERR(clk))
819 dev_warn(dev, "failed to register %s (%ld)\n",
820 child_name, PTR_ERR(clk));
821 else
822 of_clk_add_provider(child, of_clk_src_simple_get, clk);
823 }
824 of_node_put(child);
825
826 child = of_get_child_by_name(node, "obsclk");
827 if (of_device_is_available(child)) {
828 if (obsclk_info)
829 clk = davinci_pll_obsclk_register(dev, obsclk_info, base);
830 else
831 clk = ERR_PTR(-EINVAL);
832
833 if (IS_ERR(clk))
834 dev_warn(dev, "failed to register obsclk (%ld)\n",
835 PTR_ERR(clk));
836 else
837 of_clk_add_provider(child, of_clk_src_simple_get, clk);
838 }
839 of_node_put(child);
840
841 return 0;
842 }
843
davinci_pll_get_pdata(struct device * dev)844 static struct davinci_pll_platform_data *davinci_pll_get_pdata(struct device *dev)
845 {
846 struct davinci_pll_platform_data *pdata = dev_get_platdata(dev);
847
848 /*
849 * Platform data is optional, so allocate a new struct if one was not
850 * provided. For device tree, this will always be the case.
851 */
852 if (!pdata)
853 pdata = devm_kzalloc(dev, sizeof(*pdata), GFP_KERNEL);
854 if (!pdata)
855 return NULL;
856
857 /* for device tree, we need to fill in the struct */
858 if (dev->of_node)
859 pdata->cfgchip =
860 syscon_regmap_lookup_by_compatible("ti,da830-cfgchip");
861
862 return pdata;
863 }
864
865 /* needed in early boot for clocksource/clockevent */
866 #ifdef CONFIG_ARCH_DAVINCI_DA850
867 CLK_OF_DECLARE(da850_pll0, "ti,da850-pll0", of_da850_pll0_init);
868 #endif
869
870 static const struct of_device_id davinci_pll_of_match[] = {
871 #ifdef CONFIG_ARCH_DAVINCI_DA850
872 { .compatible = "ti,da850-pll1", .data = of_da850_pll1_init },
873 #endif
874 { }
875 };
876
877 static const struct platform_device_id davinci_pll_id_table[] = {
878 #ifdef CONFIG_ARCH_DAVINCI_DA830
879 { .name = "da830-pll", .driver_data = (kernel_ulong_t)da830_pll_init },
880 #endif
881 #ifdef CONFIG_ARCH_DAVINCI_DA850
882 { .name = "da850-pll0", .driver_data = (kernel_ulong_t)da850_pll0_init },
883 { .name = "da850-pll1", .driver_data = (kernel_ulong_t)da850_pll1_init },
884 #endif
885 { }
886 };
887
888 typedef int (*davinci_pll_init)(struct device *dev, void __iomem *base,
889 struct regmap *cfgchip);
890
davinci_pll_probe(struct platform_device * pdev)891 static int davinci_pll_probe(struct platform_device *pdev)
892 {
893 struct device *dev = &pdev->dev;
894 struct davinci_pll_platform_data *pdata;
895 const struct of_device_id *of_id;
896 davinci_pll_init pll_init = NULL;
897 void __iomem *base;
898
899 of_id = of_match_device(davinci_pll_of_match, dev);
900 if (of_id)
901 pll_init = of_id->data;
902 else if (pdev->id_entry)
903 pll_init = (void *)pdev->id_entry->driver_data;
904
905 if (!pll_init) {
906 dev_err(dev, "unable to find driver data\n");
907 return -EINVAL;
908 }
909
910 pdata = davinci_pll_get_pdata(dev);
911 if (!pdata) {
912 dev_err(dev, "missing platform data\n");
913 return -EINVAL;
914 }
915
916 base = devm_platform_ioremap_resource(pdev, 0);
917 if (IS_ERR(base))
918 return PTR_ERR(base);
919
920 return pll_init(dev, base, pdata->cfgchip);
921 }
922
923 static struct platform_driver davinci_pll_driver = {
924 .probe = davinci_pll_probe,
925 .driver = {
926 .name = "davinci-pll-clk",
927 .of_match_table = davinci_pll_of_match,
928 },
929 .id_table = davinci_pll_id_table,
930 };
931
davinci_pll_driver_init(void)932 static int __init davinci_pll_driver_init(void)
933 {
934 return platform_driver_register(&davinci_pll_driver);
935 }
936
937 /* has to be postcore_initcall because PSC devices depend on PLL parent clocks */
938 postcore_initcall(davinci_pll_driver_init);
939
940 #ifdef CONFIG_DEBUG_FS
941 #include <linux/debugfs.h>
942
943 #define DEBUG_REG(n) \
944 { \
945 .name = #n, \
946 .offset = n, \
947 }
948
949 static const struct debugfs_reg32 davinci_pll_regs[] = {
950 DEBUG_REG(REVID),
951 DEBUG_REG(PLLCTL),
952 DEBUG_REG(OCSEL),
953 DEBUG_REG(PLLSECCTL),
954 DEBUG_REG(PLLM),
955 DEBUG_REG(PREDIV),
956 DEBUG_REG(PLLDIV1),
957 DEBUG_REG(PLLDIV2),
958 DEBUG_REG(PLLDIV3),
959 DEBUG_REG(OSCDIV),
960 DEBUG_REG(POSTDIV),
961 DEBUG_REG(BPDIV),
962 DEBUG_REG(PLLCMD),
963 DEBUG_REG(PLLSTAT),
964 DEBUG_REG(ALNCTL),
965 DEBUG_REG(DCHANGE),
966 DEBUG_REG(CKEN),
967 DEBUG_REG(CKSTAT),
968 DEBUG_REG(SYSTAT),
969 DEBUG_REG(PLLDIV4),
970 DEBUG_REG(PLLDIV5),
971 DEBUG_REG(PLLDIV6),
972 DEBUG_REG(PLLDIV7),
973 DEBUG_REG(PLLDIV8),
974 DEBUG_REG(PLLDIV9),
975 };
976
davinci_pll_debug_init(struct clk_hw * hw,struct dentry * dentry)977 static void davinci_pll_debug_init(struct clk_hw *hw, struct dentry *dentry)
978 {
979 struct davinci_pll_clk *pll = to_davinci_pll_clk(hw);
980 struct debugfs_regset32 *regset;
981
982 regset = kzalloc(sizeof(*regset), GFP_KERNEL);
983 if (!regset)
984 return;
985
986 regset->regs = davinci_pll_regs;
987 regset->nregs = ARRAY_SIZE(davinci_pll_regs);
988 regset->base = pll->base;
989
990 debugfs_create_regset32("registers", 0400, dentry, regset);
991 }
992 #endif
993