xref: /linux/drivers/clk/renesas/renesas-cpg-mssr.c (revision 7f71507851fc7764b36a3221839607d3a45c2025)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Renesas Clock Pulse Generator / Module Standby and Software Reset
4  *
5  * Copyright (C) 2015 Glider bvba
6  *
7  * Based on clk-mstp.c, clk-rcar-gen2.c, and clk-rcar-gen3.c
8  *
9  * Copyright (C) 2013 Ideas On Board SPRL
10  * Copyright (C) 2015 Renesas Electronics Corp.
11  */
12 
13 #include <linux/clk.h>
14 #include <linux/clk-provider.h>
15 #include <linux/clk/renesas.h>
16 #include <linux/delay.h>
17 #include <linux/device.h>
18 #include <linux/init.h>
19 #include <linux/io.h>
20 #include <linux/iopoll.h>
21 #include <linux/mod_devicetable.h>
22 #include <linux/module.h>
23 #include <linux/of_address.h>
24 #include <linux/platform_device.h>
25 #include <linux/pm_clock.h>
26 #include <linux/pm_domain.h>
27 #include <linux/psci.h>
28 #include <linux/reset-controller.h>
29 #include <linux/slab.h>
30 
31 #include <dt-bindings/clock/renesas-cpg-mssr.h>
32 
33 #include "renesas-cpg-mssr.h"
34 #include "clk-div6.h"
35 
36 #ifdef DEBUG
37 #define WARN_DEBUG(x)	WARN_ON(x)
38 #else
39 #define WARN_DEBUG(x)	do { } while (0)
40 #endif
41 
42 /*
43  * Module Standby and Software Reset register offets.
44  *
45  * If the registers exist, these are valid for SH-Mobile, R-Mobile,
46  * R-Car Gen2, R-Car Gen3, and RZ/G1.
47  * These are NOT valid for R-Car Gen1 and RZ/A1!
48  */
49 
50 /*
51  * Module Stop Status Register offsets
52  */
53 
54 static const u16 mstpsr[] = {
55 	0x030, 0x038, 0x040, 0x048, 0x04C, 0x03C, 0x1C0, 0x1C4,
56 	0x9A0, 0x9A4, 0x9A8, 0x9AC,
57 };
58 
59 static const u16 mstpsr_for_gen4[] = {
60 	0x2E00, 0x2E04, 0x2E08, 0x2E0C, 0x2E10, 0x2E14, 0x2E18, 0x2E1C,
61 	0x2E20, 0x2E24, 0x2E28, 0x2E2C, 0x2E30, 0x2E34, 0x2E38, 0x2E3C,
62 	0x2E40, 0x2E44, 0x2E48, 0x2E4C, 0x2E50, 0x2E54, 0x2E58, 0x2E5C,
63 	0x2E60, 0x2E64, 0x2E68, 0x2E6C, 0x2E70, 0x2E74,
64 };
65 
66 /*
67  * System Module Stop Control Register offsets
68  */
69 
70 static const u16 smstpcr[] = {
71 	0x130, 0x134, 0x138, 0x13C, 0x140, 0x144, 0x148, 0x14C,
72 	0x990, 0x994, 0x998, 0x99C,
73 };
74 
75 static const u16 mstpcr_for_gen4[] = {
76 	0x2D00, 0x2D04, 0x2D08, 0x2D0C, 0x2D10, 0x2D14, 0x2D18, 0x2D1C,
77 	0x2D20, 0x2D24, 0x2D28, 0x2D2C, 0x2D30, 0x2D34, 0x2D38, 0x2D3C,
78 	0x2D40, 0x2D44, 0x2D48, 0x2D4C, 0x2D50, 0x2D54, 0x2D58, 0x2D5C,
79 	0x2D60, 0x2D64, 0x2D68, 0x2D6C, 0x2D70, 0x2D74,
80 };
81 
82 /*
83  * Standby Control Register offsets (RZ/A)
84  * Base address is FRQCR register
85  */
86 
87 static const u16 stbcr[] = {
88 	0xFFFF/*dummy*/, 0x010, 0x014, 0x410, 0x414, 0x418, 0x41C, 0x420,
89 	0x424, 0x428, 0x42C,
90 };
91 
92 /*
93  * Software Reset Register offsets
94  */
95 
96 static const u16 srcr[] = {
97 	0x0A0, 0x0A8, 0x0B0, 0x0B8, 0x0BC, 0x0C4, 0x1C8, 0x1CC,
98 	0x920, 0x924, 0x928, 0x92C,
99 };
100 
101 static const u16 srcr_for_gen4[] = {
102 	0x2C00, 0x2C04, 0x2C08, 0x2C0C, 0x2C10, 0x2C14, 0x2C18, 0x2C1C,
103 	0x2C20, 0x2C24, 0x2C28, 0x2C2C, 0x2C30, 0x2C34, 0x2C38, 0x2C3C,
104 	0x2C40, 0x2C44, 0x2C48, 0x2C4C, 0x2C50, 0x2C54, 0x2C58, 0x2C5C,
105 	0x2C60, 0x2C64, 0x2C68, 0x2C6C, 0x2C70, 0x2C74,
106 };
107 
108 /*
109  * Software Reset Clearing Register offsets
110  */
111 
112 static const u16 srstclr[] = {
113 	0x940, 0x944, 0x948, 0x94C, 0x950, 0x954, 0x958, 0x95C,
114 	0x960, 0x964, 0x968, 0x96C,
115 };
116 
117 static const u16 srstclr_for_gen4[] = {
118 	0x2C80, 0x2C84, 0x2C88, 0x2C8C, 0x2C90, 0x2C94, 0x2C98, 0x2C9C,
119 	0x2CA0, 0x2CA4, 0x2CA8, 0x2CAC, 0x2CB0, 0x2CB4, 0x2CB8, 0x2CBC,
120 	0x2CC0, 0x2CC4, 0x2CC8, 0x2CCC, 0x2CD0, 0x2CD4, 0x2CD8, 0x2CDC,
121 	0x2CE0, 0x2CE4, 0x2CE8, 0x2CEC, 0x2CF0, 0x2CF4,
122 };
123 
124 /**
125  * struct cpg_mssr_priv - Clock Pulse Generator / Module Standby
126  *                        and Software Reset Private Data
127  *
128  * @rcdev: Optional reset controller entity
129  * @dev: CPG/MSSR device
130  * @base: CPG/MSSR register block base address
131  * @reg_layout: CPG/MSSR register layout
132  * @rmw_lock: protects RMW register accesses
133  * @np: Device node in DT for this CPG/MSSR module
134  * @num_core_clks: Number of Core Clocks in clks[]
135  * @num_mod_clks: Number of Module Clocks in clks[]
136  * @last_dt_core_clk: ID of the last Core Clock exported to DT
137  * @notifiers: Notifier chain to save/restore clock state for system resume
138  * @status_regs: Pointer to status registers array
139  * @control_regs: Pointer to control registers array
140  * @reset_regs: Pointer to reset registers array
141  * @reset_clear_regs:  Pointer to reset clearing registers array
142  * @smstpcr_saved: [].mask: Mask of SMSTPCR[] bits under our control
143  *                 [].val: Saved values of SMSTPCR[]
144  * @reserved_ids: Temporary used, reserved id list
145  * @num_reserved_ids: Temporary used, number of reserved id list
146  * @clks: Array containing all Core and Module Clocks
147  */
148 struct cpg_mssr_priv {
149 #ifdef CONFIG_RESET_CONTROLLER
150 	struct reset_controller_dev rcdev;
151 #endif
152 	struct device *dev;
153 	void __iomem *base;
154 	enum clk_reg_layout reg_layout;
155 	spinlock_t rmw_lock;
156 	struct device_node *np;
157 
158 	unsigned int num_core_clks;
159 	unsigned int num_mod_clks;
160 	unsigned int last_dt_core_clk;
161 
162 	struct raw_notifier_head notifiers;
163 	const u16 *status_regs;
164 	const u16 *control_regs;
165 	const u16 *reset_regs;
166 	const u16 *reset_clear_regs;
167 	struct {
168 		u32 mask;
169 		u32 val;
170 	} smstpcr_saved[ARRAY_SIZE(mstpsr_for_gen4)];
171 
172 	unsigned int *reserved_ids;
173 	unsigned int num_reserved_ids;
174 
175 	struct clk *clks[];
176 };
177 
178 static struct cpg_mssr_priv *cpg_mssr_priv;
179 
180 /**
181  * struct mstp_clock - MSTP gating clock
182  * @hw: handle between common and hardware-specific interfaces
183  * @index: MSTP clock number
184  * @priv: CPG/MSSR private data
185  */
186 struct mstp_clock {
187 	struct clk_hw hw;
188 	u32 index;
189 	struct cpg_mssr_priv *priv;
190 };
191 
192 #define to_mstp_clock(_hw) container_of(_hw, struct mstp_clock, hw)
193 
194 static int cpg_mstp_clock_endisable(struct clk_hw *hw, bool enable)
195 {
196 	struct mstp_clock *clock = to_mstp_clock(hw);
197 	struct cpg_mssr_priv *priv = clock->priv;
198 	unsigned int reg = clock->index / 32;
199 	unsigned int bit = clock->index % 32;
200 	struct device *dev = priv->dev;
201 	u32 bitmask = BIT(bit);
202 	unsigned long flags;
203 	u32 value;
204 	int error;
205 
206 	dev_dbg(dev, "MSTP %u%02u/%pC %s\n", reg, bit, hw->clk,
207 		enable ? "ON" : "OFF");
208 	spin_lock_irqsave(&priv->rmw_lock, flags);
209 
210 	if (priv->reg_layout == CLK_REG_LAYOUT_RZ_A) {
211 		value = readb(priv->base + priv->control_regs[reg]);
212 		if (enable)
213 			value &= ~bitmask;
214 		else
215 			value |= bitmask;
216 		writeb(value, priv->base + priv->control_regs[reg]);
217 
218 		/* dummy read to ensure write has completed */
219 		readb(priv->base + priv->control_regs[reg]);
220 		barrier_data(priv->base + priv->control_regs[reg]);
221 	} else {
222 		value = readl(priv->base + priv->control_regs[reg]);
223 		if (enable)
224 			value &= ~bitmask;
225 		else
226 			value |= bitmask;
227 		writel(value, priv->base + priv->control_regs[reg]);
228 	}
229 
230 	spin_unlock_irqrestore(&priv->rmw_lock, flags);
231 
232 	if (!enable || priv->reg_layout == CLK_REG_LAYOUT_RZ_A)
233 		return 0;
234 
235 	error = readl_poll_timeout_atomic(priv->base + priv->status_regs[reg],
236 					  value, !(value & bitmask), 0, 10);
237 	if (error)
238 		dev_err(dev, "Failed to enable SMSTP %p[%d]\n",
239 			priv->base + priv->control_regs[reg], bit);
240 
241 	return error;
242 }
243 
244 static int cpg_mstp_clock_enable(struct clk_hw *hw)
245 {
246 	return cpg_mstp_clock_endisable(hw, true);
247 }
248 
249 static void cpg_mstp_clock_disable(struct clk_hw *hw)
250 {
251 	cpg_mstp_clock_endisable(hw, false);
252 }
253 
254 static int cpg_mstp_clock_is_enabled(struct clk_hw *hw)
255 {
256 	struct mstp_clock *clock = to_mstp_clock(hw);
257 	struct cpg_mssr_priv *priv = clock->priv;
258 	u32 value;
259 
260 	if (priv->reg_layout == CLK_REG_LAYOUT_RZ_A)
261 		value = readb(priv->base + priv->control_regs[clock->index / 32]);
262 	else
263 		value = readl(priv->base + priv->status_regs[clock->index / 32]);
264 
265 	return !(value & BIT(clock->index % 32));
266 }
267 
268 static const struct clk_ops cpg_mstp_clock_ops = {
269 	.enable = cpg_mstp_clock_enable,
270 	.disable = cpg_mstp_clock_disable,
271 	.is_enabled = cpg_mstp_clock_is_enabled,
272 };
273 
274 static
275 struct clk *cpg_mssr_clk_src_twocell_get(struct of_phandle_args *clkspec,
276 					 void *data)
277 {
278 	unsigned int clkidx = clkspec->args[1];
279 	struct cpg_mssr_priv *priv = data;
280 	struct device *dev = priv->dev;
281 	unsigned int idx;
282 	const char *type;
283 	struct clk *clk;
284 	int range_check;
285 
286 	switch (clkspec->args[0]) {
287 	case CPG_CORE:
288 		type = "core";
289 		if (clkidx > priv->last_dt_core_clk) {
290 			dev_err(dev, "Invalid %s clock index %u\n", type,
291 			       clkidx);
292 			return ERR_PTR(-EINVAL);
293 		}
294 		clk = priv->clks[clkidx];
295 		break;
296 
297 	case CPG_MOD:
298 		type = "module";
299 		if (priv->reg_layout == CLK_REG_LAYOUT_RZ_A) {
300 			idx = MOD_CLK_PACK_10(clkidx);
301 			range_check = 7 - (clkidx % 10);
302 		} else {
303 			idx = MOD_CLK_PACK(clkidx);
304 			range_check = 31 - (clkidx % 100);
305 		}
306 		if (range_check < 0 || idx >= priv->num_mod_clks) {
307 			dev_err(dev, "Invalid %s clock index %u\n", type,
308 				clkidx);
309 			return ERR_PTR(-EINVAL);
310 		}
311 		clk = priv->clks[priv->num_core_clks + idx];
312 		break;
313 
314 	default:
315 		dev_err(dev, "Invalid CPG clock type %u\n", clkspec->args[0]);
316 		return ERR_PTR(-EINVAL);
317 	}
318 
319 	if (IS_ERR(clk))
320 		dev_err(dev, "Cannot get %s clock %u: %ld", type, clkidx,
321 		       PTR_ERR(clk));
322 	else
323 		dev_dbg(dev, "clock (%u, %u) is %pC at %lu Hz\n",
324 			clkspec->args[0], clkspec->args[1], clk,
325 			clk_get_rate(clk));
326 	return clk;
327 }
328 
329 static void __init cpg_mssr_register_core_clk(const struct cpg_core_clk *core,
330 					      const struct cpg_mssr_info *info,
331 					      struct cpg_mssr_priv *priv)
332 {
333 	struct clk *clk = ERR_PTR(-ENOTSUPP), *parent;
334 	struct device *dev = priv->dev;
335 	unsigned int id = core->id, div = core->div;
336 	const char *parent_name;
337 
338 	WARN_DEBUG(id >= priv->num_core_clks);
339 	WARN_DEBUG(PTR_ERR(priv->clks[id]) != -ENOENT);
340 
341 	if (!core->name) {
342 		/* Skip NULLified clock */
343 		return;
344 	}
345 
346 	switch (core->type) {
347 	case CLK_TYPE_IN:
348 		clk = of_clk_get_by_name(priv->np, core->name);
349 		break;
350 
351 	case CLK_TYPE_FF:
352 	case CLK_TYPE_DIV6P1:
353 	case CLK_TYPE_DIV6_RO:
354 		WARN_DEBUG(core->parent >= priv->num_core_clks);
355 		parent = priv->clks[core->parent];
356 		if (IS_ERR(parent)) {
357 			clk = parent;
358 			goto fail;
359 		}
360 
361 		parent_name = __clk_get_name(parent);
362 
363 		if (core->type == CLK_TYPE_DIV6_RO)
364 			/* Multiply with the DIV6 register value */
365 			div *= (readl(priv->base + core->offset) & 0x3f) + 1;
366 
367 		if (core->type == CLK_TYPE_DIV6P1) {
368 			clk = cpg_div6_register(core->name, 1, &parent_name,
369 						priv->base + core->offset,
370 						&priv->notifiers);
371 		} else {
372 			clk = clk_register_fixed_factor(NULL, core->name,
373 							parent_name, 0,
374 							core->mult, div);
375 		}
376 		break;
377 
378 	case CLK_TYPE_FR:
379 		clk = clk_register_fixed_rate(NULL, core->name, NULL, 0,
380 					      core->mult);
381 		break;
382 
383 	default:
384 		if (info->cpg_clk_register)
385 			clk = info->cpg_clk_register(dev, core, info,
386 						     priv->clks, priv->base,
387 						     &priv->notifiers);
388 		else
389 			dev_err(dev, "%s has unsupported core clock type %u\n",
390 				core->name, core->type);
391 		break;
392 	}
393 
394 	if (IS_ERR_OR_NULL(clk))
395 		goto fail;
396 
397 	dev_dbg(dev, "Core clock %pC at %lu Hz\n", clk, clk_get_rate(clk));
398 	priv->clks[id] = clk;
399 	return;
400 
401 fail:
402 	dev_err(dev, "Failed to register %s clock %s: %ld\n", "core",
403 		core->name, PTR_ERR(clk));
404 }
405 
406 static void __init cpg_mssr_register_mod_clk(const struct mssr_mod_clk *mod,
407 					     const struct cpg_mssr_info *info,
408 					     struct cpg_mssr_priv *priv)
409 {
410 	struct mstp_clock *clock = NULL;
411 	struct device *dev = priv->dev;
412 	unsigned int id = mod->id;
413 	struct clk_init_data init = {};
414 	struct clk *parent, *clk;
415 	const char *parent_name;
416 	unsigned int i;
417 
418 	WARN_DEBUG(id < priv->num_core_clks);
419 	WARN_DEBUG(id >= priv->num_core_clks + priv->num_mod_clks);
420 	WARN_DEBUG(mod->parent >= priv->num_core_clks + priv->num_mod_clks);
421 	WARN_DEBUG(PTR_ERR(priv->clks[id]) != -ENOENT);
422 
423 	if (!mod->name) {
424 		/* Skip NULLified clock */
425 		return;
426 	}
427 
428 	parent = priv->clks[mod->parent];
429 	if (IS_ERR(parent)) {
430 		clk = parent;
431 		goto fail;
432 	}
433 
434 	clock = kzalloc(sizeof(*clock), GFP_KERNEL);
435 	if (!clock) {
436 		clk = ERR_PTR(-ENOMEM);
437 		goto fail;
438 	}
439 
440 	init.name = mod->name;
441 	init.ops = &cpg_mstp_clock_ops;
442 	init.flags = CLK_SET_RATE_PARENT;
443 	parent_name = __clk_get_name(parent);
444 	init.parent_names = &parent_name;
445 	init.num_parents = 1;
446 
447 	clock->index = id - priv->num_core_clks;
448 	clock->priv = priv;
449 	clock->hw.init = &init;
450 
451 	for (i = 0; i < info->num_crit_mod_clks; i++)
452 		if (id == info->crit_mod_clks[i] &&
453 		    cpg_mstp_clock_is_enabled(&clock->hw)) {
454 			dev_dbg(dev, "MSTP %s setting CLK_IS_CRITICAL\n",
455 				mod->name);
456 			init.flags |= CLK_IS_CRITICAL;
457 			break;
458 		}
459 
460 	/*
461 	 * Ignore reserved device.
462 	 * see
463 	 *	cpg_mssr_reserved_init()
464 	 */
465 	for (i = 0; i < priv->num_reserved_ids; i++) {
466 		if (id == priv->reserved_ids[i]) {
467 			dev_info(dev, "Ignore Linux non-assigned mod (%s)\n", mod->name);
468 			init.flags |= CLK_IGNORE_UNUSED;
469 			break;
470 		}
471 	}
472 
473 	clk = clk_register(NULL, &clock->hw);
474 	if (IS_ERR(clk))
475 		goto fail;
476 
477 	dev_dbg(dev, "Module clock %pC at %lu Hz\n", clk, clk_get_rate(clk));
478 	priv->clks[id] = clk;
479 	priv->smstpcr_saved[clock->index / 32].mask |= BIT(clock->index % 32);
480 	return;
481 
482 fail:
483 	dev_err(dev, "Failed to register %s clock %s: %ld\n", "module",
484 		mod->name, PTR_ERR(clk));
485 	kfree(clock);
486 }
487 
488 struct cpg_mssr_clk_domain {
489 	struct generic_pm_domain genpd;
490 	unsigned int num_core_pm_clks;
491 	unsigned int core_pm_clks[];
492 };
493 
494 static struct cpg_mssr_clk_domain *cpg_mssr_clk_domain;
495 
496 static bool cpg_mssr_is_pm_clk(const struct of_phandle_args *clkspec,
497 			       struct cpg_mssr_clk_domain *pd)
498 {
499 	unsigned int i;
500 
501 	if (clkspec->np != pd->genpd.dev.of_node || clkspec->args_count != 2)
502 		return false;
503 
504 	switch (clkspec->args[0]) {
505 	case CPG_CORE:
506 		for (i = 0; i < pd->num_core_pm_clks; i++)
507 			if (clkspec->args[1] == pd->core_pm_clks[i])
508 				return true;
509 		return false;
510 
511 	case CPG_MOD:
512 		return true;
513 
514 	default:
515 		return false;
516 	}
517 }
518 
519 int cpg_mssr_attach_dev(struct generic_pm_domain *unused, struct device *dev)
520 {
521 	struct cpg_mssr_clk_domain *pd = cpg_mssr_clk_domain;
522 	struct device_node *np = dev->of_node;
523 	struct of_phandle_args clkspec;
524 	struct clk *clk;
525 	int i = 0;
526 	int error;
527 
528 	if (!pd) {
529 		dev_dbg(dev, "CPG/MSSR clock domain not yet available\n");
530 		return -EPROBE_DEFER;
531 	}
532 
533 	while (!of_parse_phandle_with_args(np, "clocks", "#clock-cells", i,
534 					   &clkspec)) {
535 		if (cpg_mssr_is_pm_clk(&clkspec, pd))
536 			goto found;
537 
538 		of_node_put(clkspec.np);
539 		i++;
540 	}
541 
542 	return 0;
543 
544 found:
545 	clk = of_clk_get_from_provider(&clkspec);
546 	of_node_put(clkspec.np);
547 
548 	if (IS_ERR(clk))
549 		return PTR_ERR(clk);
550 
551 	error = pm_clk_create(dev);
552 	if (error)
553 		goto fail_put;
554 
555 	error = pm_clk_add_clk(dev, clk);
556 	if (error)
557 		goto fail_destroy;
558 
559 	return 0;
560 
561 fail_destroy:
562 	pm_clk_destroy(dev);
563 fail_put:
564 	clk_put(clk);
565 	return error;
566 }
567 
568 void cpg_mssr_detach_dev(struct generic_pm_domain *unused, struct device *dev)
569 {
570 	if (!pm_clk_no_clocks(dev))
571 		pm_clk_destroy(dev);
572 }
573 
574 static void cpg_mssr_genpd_remove(void *data)
575 {
576 	pm_genpd_remove(data);
577 }
578 
579 static int __init cpg_mssr_add_clk_domain(struct device *dev,
580 					  const unsigned int *core_pm_clks,
581 					  unsigned int num_core_pm_clks)
582 {
583 	struct device_node *np = dev->of_node;
584 	struct generic_pm_domain *genpd;
585 	struct cpg_mssr_clk_domain *pd;
586 	size_t pm_size = num_core_pm_clks * sizeof(core_pm_clks[0]);
587 	int ret;
588 
589 	pd = devm_kzalloc(dev, sizeof(*pd) + pm_size, GFP_KERNEL);
590 	if (!pd)
591 		return -ENOMEM;
592 
593 	pd->num_core_pm_clks = num_core_pm_clks;
594 	memcpy(pd->core_pm_clks, core_pm_clks, pm_size);
595 
596 	genpd = &pd->genpd;
597 	genpd->name = np->name;
598 	genpd->flags = GENPD_FLAG_PM_CLK | GENPD_FLAG_ALWAYS_ON |
599 		       GENPD_FLAG_ACTIVE_WAKEUP;
600 	genpd->attach_dev = cpg_mssr_attach_dev;
601 	genpd->detach_dev = cpg_mssr_detach_dev;
602 	ret = pm_genpd_init(genpd, &pm_domain_always_on_gov, false);
603 	if (ret)
604 		return ret;
605 
606 	ret = devm_add_action_or_reset(dev, cpg_mssr_genpd_remove, genpd);
607 	if (ret)
608 		return ret;
609 
610 	cpg_mssr_clk_domain = pd;
611 
612 	return of_genpd_add_provider_simple(np, genpd);
613 }
614 
615 #ifdef CONFIG_RESET_CONTROLLER
616 
617 #define rcdev_to_priv(x)	container_of(x, struct cpg_mssr_priv, rcdev)
618 
619 static int cpg_mssr_reset(struct reset_controller_dev *rcdev,
620 			  unsigned long id)
621 {
622 	struct cpg_mssr_priv *priv = rcdev_to_priv(rcdev);
623 	unsigned int reg = id / 32;
624 	unsigned int bit = id % 32;
625 	u32 bitmask = BIT(bit);
626 
627 	dev_dbg(priv->dev, "reset %u%02u\n", reg, bit);
628 
629 	/* Reset module */
630 	writel(bitmask, priv->base + priv->reset_regs[reg]);
631 
632 	/* Wait for at least one cycle of the RCLK clock (@ ca. 32 kHz) */
633 	udelay(35);
634 
635 	/* Release module from reset state */
636 	writel(bitmask, priv->base + priv->reset_clear_regs[reg]);
637 
638 	return 0;
639 }
640 
641 static int cpg_mssr_assert(struct reset_controller_dev *rcdev, unsigned long id)
642 {
643 	struct cpg_mssr_priv *priv = rcdev_to_priv(rcdev);
644 	unsigned int reg = id / 32;
645 	unsigned int bit = id % 32;
646 	u32 bitmask = BIT(bit);
647 
648 	dev_dbg(priv->dev, "assert %u%02u\n", reg, bit);
649 
650 	writel(bitmask, priv->base + priv->reset_regs[reg]);
651 	return 0;
652 }
653 
654 static int cpg_mssr_deassert(struct reset_controller_dev *rcdev,
655 			     unsigned long id)
656 {
657 	struct cpg_mssr_priv *priv = rcdev_to_priv(rcdev);
658 	unsigned int reg = id / 32;
659 	unsigned int bit = id % 32;
660 	u32 bitmask = BIT(bit);
661 
662 	dev_dbg(priv->dev, "deassert %u%02u\n", reg, bit);
663 
664 	writel(bitmask, priv->base + priv->reset_clear_regs[reg]);
665 	return 0;
666 }
667 
668 static int cpg_mssr_status(struct reset_controller_dev *rcdev,
669 			   unsigned long id)
670 {
671 	struct cpg_mssr_priv *priv = rcdev_to_priv(rcdev);
672 	unsigned int reg = id / 32;
673 	unsigned int bit = id % 32;
674 	u32 bitmask = BIT(bit);
675 
676 	return !!(readl(priv->base + priv->reset_regs[reg]) & bitmask);
677 }
678 
679 static const struct reset_control_ops cpg_mssr_reset_ops = {
680 	.reset = cpg_mssr_reset,
681 	.assert = cpg_mssr_assert,
682 	.deassert = cpg_mssr_deassert,
683 	.status = cpg_mssr_status,
684 };
685 
686 static int cpg_mssr_reset_xlate(struct reset_controller_dev *rcdev,
687 				const struct of_phandle_args *reset_spec)
688 {
689 	struct cpg_mssr_priv *priv = rcdev_to_priv(rcdev);
690 	unsigned int unpacked = reset_spec->args[0];
691 	unsigned int idx = MOD_CLK_PACK(unpacked);
692 
693 	if (unpacked % 100 > 31 || idx >= rcdev->nr_resets) {
694 		dev_err(priv->dev, "Invalid reset index %u\n", unpacked);
695 		return -EINVAL;
696 	}
697 
698 	return idx;
699 }
700 
701 static int cpg_mssr_reset_controller_register(struct cpg_mssr_priv *priv)
702 {
703 	priv->rcdev.ops = &cpg_mssr_reset_ops;
704 	priv->rcdev.of_node = priv->dev->of_node;
705 	priv->rcdev.of_reset_n_cells = 1;
706 	priv->rcdev.of_xlate = cpg_mssr_reset_xlate;
707 	priv->rcdev.nr_resets = priv->num_mod_clks;
708 	return devm_reset_controller_register(priv->dev, &priv->rcdev);
709 }
710 
711 #else /* !CONFIG_RESET_CONTROLLER */
712 static inline int cpg_mssr_reset_controller_register(struct cpg_mssr_priv *priv)
713 {
714 	return 0;
715 }
716 #endif /* !CONFIG_RESET_CONTROLLER */
717 
718 static const struct of_device_id cpg_mssr_match[] = {
719 #ifdef CONFIG_CLK_R7S9210
720 	{
721 		.compatible = "renesas,r7s9210-cpg-mssr",
722 		.data = &r7s9210_cpg_mssr_info,
723 	},
724 #endif
725 #ifdef CONFIG_CLK_R8A7742
726 	{
727 		.compatible = "renesas,r8a7742-cpg-mssr",
728 		.data = &r8a7742_cpg_mssr_info,
729 	},
730 #endif
731 #ifdef CONFIG_CLK_R8A7743
732 	{
733 		.compatible = "renesas,r8a7743-cpg-mssr",
734 		.data = &r8a7743_cpg_mssr_info,
735 	},
736 	/* RZ/G1N is (almost) identical to RZ/G1M w.r.t. clocks. */
737 	{
738 		.compatible = "renesas,r8a7744-cpg-mssr",
739 		.data = &r8a7743_cpg_mssr_info,
740 	},
741 #endif
742 #ifdef CONFIG_CLK_R8A7745
743 	{
744 		.compatible = "renesas,r8a7745-cpg-mssr",
745 		.data = &r8a7745_cpg_mssr_info,
746 	},
747 #endif
748 #ifdef CONFIG_CLK_R8A77470
749 	{
750 		.compatible = "renesas,r8a77470-cpg-mssr",
751 		.data = &r8a77470_cpg_mssr_info,
752 	},
753 #endif
754 #ifdef CONFIG_CLK_R8A774A1
755 	{
756 		.compatible = "renesas,r8a774a1-cpg-mssr",
757 		.data = &r8a774a1_cpg_mssr_info,
758 	},
759 #endif
760 #ifdef CONFIG_CLK_R8A774B1
761 	{
762 		.compatible = "renesas,r8a774b1-cpg-mssr",
763 		.data = &r8a774b1_cpg_mssr_info,
764 	},
765 #endif
766 #ifdef CONFIG_CLK_R8A774C0
767 	{
768 		.compatible = "renesas,r8a774c0-cpg-mssr",
769 		.data = &r8a774c0_cpg_mssr_info,
770 	},
771 #endif
772 #ifdef CONFIG_CLK_R8A774E1
773 	{
774 		.compatible = "renesas,r8a774e1-cpg-mssr",
775 		.data = &r8a774e1_cpg_mssr_info,
776 	},
777 #endif
778 #ifdef CONFIG_CLK_R8A7790
779 	{
780 		.compatible = "renesas,r8a7790-cpg-mssr",
781 		.data = &r8a7790_cpg_mssr_info,
782 	},
783 #endif
784 #ifdef CONFIG_CLK_R8A7791
785 	{
786 		.compatible = "renesas,r8a7791-cpg-mssr",
787 		.data = &r8a7791_cpg_mssr_info,
788 	},
789 	/* R-Car M2-N is (almost) identical to R-Car M2-W w.r.t. clocks. */
790 	{
791 		.compatible = "renesas,r8a7793-cpg-mssr",
792 		.data = &r8a7791_cpg_mssr_info,
793 	},
794 #endif
795 #ifdef CONFIG_CLK_R8A7792
796 	{
797 		.compatible = "renesas,r8a7792-cpg-mssr",
798 		.data = &r8a7792_cpg_mssr_info,
799 	},
800 #endif
801 #ifdef CONFIG_CLK_R8A7794
802 	{
803 		.compatible = "renesas,r8a7794-cpg-mssr",
804 		.data = &r8a7794_cpg_mssr_info,
805 	},
806 #endif
807 #ifdef CONFIG_CLK_R8A7795
808 	{
809 		.compatible = "renesas,r8a7795-cpg-mssr",
810 		.data = &r8a7795_cpg_mssr_info,
811 	},
812 #endif
813 #ifdef CONFIG_CLK_R8A77960
814 	{
815 		.compatible = "renesas,r8a7796-cpg-mssr",
816 		.data = &r8a7796_cpg_mssr_info,
817 	},
818 #endif
819 #ifdef CONFIG_CLK_R8A77961
820 	{
821 		.compatible = "renesas,r8a77961-cpg-mssr",
822 		.data = &r8a7796_cpg_mssr_info,
823 	},
824 #endif
825 #ifdef CONFIG_CLK_R8A77965
826 	{
827 		.compatible = "renesas,r8a77965-cpg-mssr",
828 		.data = &r8a77965_cpg_mssr_info,
829 	},
830 #endif
831 #ifdef CONFIG_CLK_R8A77970
832 	{
833 		.compatible = "renesas,r8a77970-cpg-mssr",
834 		.data = &r8a77970_cpg_mssr_info,
835 	},
836 #endif
837 #ifdef CONFIG_CLK_R8A77980
838 	{
839 		.compatible = "renesas,r8a77980-cpg-mssr",
840 		.data = &r8a77980_cpg_mssr_info,
841 	},
842 #endif
843 #ifdef CONFIG_CLK_R8A77990
844 	{
845 		.compatible = "renesas,r8a77990-cpg-mssr",
846 		.data = &r8a77990_cpg_mssr_info,
847 	},
848 #endif
849 #ifdef CONFIG_CLK_R8A77995
850 	{
851 		.compatible = "renesas,r8a77995-cpg-mssr",
852 		.data = &r8a77995_cpg_mssr_info,
853 	},
854 #endif
855 #ifdef CONFIG_CLK_R8A779A0
856 	{
857 		.compatible = "renesas,r8a779a0-cpg-mssr",
858 		.data = &r8a779a0_cpg_mssr_info,
859 	},
860 #endif
861 #ifdef CONFIG_CLK_R8A779F0
862 	{
863 		.compatible = "renesas,r8a779f0-cpg-mssr",
864 		.data = &r8a779f0_cpg_mssr_info,
865 	},
866 #endif
867 #ifdef CONFIG_CLK_R8A779G0
868 	{
869 		.compatible = "renesas,r8a779g0-cpg-mssr",
870 		.data = &r8a779g0_cpg_mssr_info,
871 	},
872 #endif
873 #ifdef CONFIG_CLK_R8A779H0
874 	{
875 		.compatible = "renesas,r8a779h0-cpg-mssr",
876 		.data = &r8a779h0_cpg_mssr_info,
877 	},
878 #endif
879 	{ /* sentinel */ }
880 };
881 
882 static void cpg_mssr_del_clk_provider(void *data)
883 {
884 	of_clk_del_provider(data);
885 }
886 
887 #if defined(CONFIG_PM_SLEEP) && defined(CONFIG_ARM_PSCI_FW)
888 static int cpg_mssr_suspend_noirq(struct device *dev)
889 {
890 	struct cpg_mssr_priv *priv = dev_get_drvdata(dev);
891 	unsigned int reg;
892 
893 	/* This is the best we can do to check for the presence of PSCI */
894 	if (!psci_ops.cpu_suspend)
895 		return 0;
896 
897 	/* Save module registers with bits under our control */
898 	for (reg = 0; reg < ARRAY_SIZE(priv->smstpcr_saved); reg++) {
899 		if (priv->smstpcr_saved[reg].mask)
900 			priv->smstpcr_saved[reg].val =
901 				priv->reg_layout == CLK_REG_LAYOUT_RZ_A ?
902 				readb(priv->base + priv->control_regs[reg]) :
903 				readl(priv->base + priv->control_regs[reg]);
904 	}
905 
906 	/* Save core clocks */
907 	raw_notifier_call_chain(&priv->notifiers, PM_EVENT_SUSPEND, NULL);
908 
909 	return 0;
910 }
911 
912 static int cpg_mssr_resume_noirq(struct device *dev)
913 {
914 	struct cpg_mssr_priv *priv = dev_get_drvdata(dev);
915 	unsigned int reg;
916 	u32 mask, oldval, newval;
917 	int error;
918 
919 	/* This is the best we can do to check for the presence of PSCI */
920 	if (!psci_ops.cpu_suspend)
921 		return 0;
922 
923 	/* Restore core clocks */
924 	raw_notifier_call_chain(&priv->notifiers, PM_EVENT_RESUME, NULL);
925 
926 	/* Restore module clocks */
927 	for (reg = 0; reg < ARRAY_SIZE(priv->smstpcr_saved); reg++) {
928 		mask = priv->smstpcr_saved[reg].mask;
929 		if (!mask)
930 			continue;
931 
932 		if (priv->reg_layout == CLK_REG_LAYOUT_RZ_A)
933 			oldval = readb(priv->base + priv->control_regs[reg]);
934 		else
935 			oldval = readl(priv->base + priv->control_regs[reg]);
936 		newval = oldval & ~mask;
937 		newval |= priv->smstpcr_saved[reg].val & mask;
938 		if (newval == oldval)
939 			continue;
940 
941 		if (priv->reg_layout == CLK_REG_LAYOUT_RZ_A) {
942 			writeb(newval, priv->base + priv->control_regs[reg]);
943 			/* dummy read to ensure write has completed */
944 			readb(priv->base + priv->control_regs[reg]);
945 			barrier_data(priv->base + priv->control_regs[reg]);
946 			continue;
947 		} else
948 			writel(newval, priv->base + priv->control_regs[reg]);
949 
950 		/* Wait until enabled clocks are really enabled */
951 		mask &= ~priv->smstpcr_saved[reg].val;
952 		if (!mask)
953 			continue;
954 
955 		error = readl_poll_timeout_atomic(priv->base + priv->status_regs[reg],
956 						oldval, !(oldval & mask), 0, 10);
957 		if (error)
958 			dev_warn(dev, "Failed to enable SMSTP%u[0x%x]\n", reg,
959 				 oldval & mask);
960 	}
961 
962 	return 0;
963 }
964 
965 static const struct dev_pm_ops cpg_mssr_pm = {
966 	SET_NOIRQ_SYSTEM_SLEEP_PM_OPS(cpg_mssr_suspend_noirq,
967 				      cpg_mssr_resume_noirq)
968 };
969 #define DEV_PM_OPS	&cpg_mssr_pm
970 #else
971 #define DEV_PM_OPS	NULL
972 #endif /* CONFIG_PM_SLEEP && CONFIG_ARM_PSCI_FW */
973 
974 static void __init cpg_mssr_reserved_exit(struct cpg_mssr_priv *priv)
975 {
976 	kfree(priv->reserved_ids);
977 }
978 
979 static int __init cpg_mssr_reserved_init(struct cpg_mssr_priv *priv,
980 					 const struct cpg_mssr_info *info)
981 {
982 	struct device_node *soc = of_find_node_by_path("/soc");
983 	struct device_node *node;
984 	uint32_t args[MAX_PHANDLE_ARGS];
985 	unsigned int *ids = NULL;
986 	unsigned int num = 0;
987 
988 	/*
989 	 * Because clk_disable_unused() will disable all unused clocks, the device which is assigned
990 	 * to a non-Linux system will be disabled when Linux is booted.
991 	 *
992 	 * To avoid such situation, renesas-cpg-mssr assumes the device which has
993 	 * status = "reserved" is assigned to a non-Linux system, and adds CLK_IGNORE_UNUSED flag
994 	 * to its CPG_MOD clocks.
995 	 * see also
996 	 *	cpg_mssr_register_mod_clk()
997 	 *
998 	 *	scif5: serial@e6f30000 {
999 	 *		...
1000 	 * =>		clocks = <&cpg CPG_MOD 202>,
1001 	 *			 <&cpg CPG_CORE R8A7795_CLK_S3D1>,
1002 	 *			 <&scif_clk>;
1003 	 *			 ...
1004 	 *		 status = "reserved";
1005 	 *	};
1006 	 */
1007 	for_each_reserved_child_of_node(soc, node) {
1008 		struct of_phandle_iterator it;
1009 		int rc;
1010 
1011 		of_for_each_phandle(&it, rc, node, "clocks", "#clock-cells", -1) {
1012 			int idx;
1013 
1014 			if (it.node != priv->np)
1015 				continue;
1016 
1017 			if (of_phandle_iterator_args(&it, args, MAX_PHANDLE_ARGS) != 2)
1018 				continue;
1019 
1020 			if (args[0] != CPG_MOD)
1021 				continue;
1022 
1023 			ids = krealloc_array(ids, (num + 1), sizeof(*ids), GFP_KERNEL);
1024 			if (!ids) {
1025 				of_node_put(it.node);
1026 				return -ENOMEM;
1027 			}
1028 
1029 			if (priv->reg_layout == CLK_REG_LAYOUT_RZ_A)
1030 				idx = MOD_CLK_PACK_10(args[1]);	/* for DEF_MOD_STB() */
1031 			else
1032 				idx = MOD_CLK_PACK(args[1]);	/* for DEF_MOD() */
1033 
1034 			ids[num] = info->num_total_core_clks + idx;
1035 
1036 			num++;
1037 		}
1038 	}
1039 
1040 	priv->num_reserved_ids	= num;
1041 	priv->reserved_ids	= ids;
1042 
1043 	return 0;
1044 }
1045 
1046 static int __init cpg_mssr_common_init(struct device *dev,
1047 				       struct device_node *np,
1048 				       const struct cpg_mssr_info *info)
1049 {
1050 	struct cpg_mssr_priv *priv;
1051 	unsigned int nclks, i;
1052 	int error;
1053 
1054 	if (info->init) {
1055 		error = info->init(dev);
1056 		if (error)
1057 			return error;
1058 	}
1059 
1060 	nclks = info->num_total_core_clks + info->num_hw_mod_clks;
1061 	priv = kzalloc(struct_size(priv, clks, nclks), GFP_KERNEL);
1062 	if (!priv)
1063 		return -ENOMEM;
1064 
1065 	priv->np = np;
1066 	priv->dev = dev;
1067 	spin_lock_init(&priv->rmw_lock);
1068 
1069 	priv->base = of_iomap(np, 0);
1070 	if (!priv->base) {
1071 		error = -ENOMEM;
1072 		goto out_err;
1073 	}
1074 
1075 	priv->num_core_clks = info->num_total_core_clks;
1076 	priv->num_mod_clks = info->num_hw_mod_clks;
1077 	priv->last_dt_core_clk = info->last_dt_core_clk;
1078 	RAW_INIT_NOTIFIER_HEAD(&priv->notifiers);
1079 	priv->reg_layout = info->reg_layout;
1080 	if (priv->reg_layout == CLK_REG_LAYOUT_RCAR_GEN2_AND_GEN3) {
1081 		priv->status_regs = mstpsr;
1082 		priv->control_regs = smstpcr;
1083 		priv->reset_regs = srcr;
1084 		priv->reset_clear_regs = srstclr;
1085 	} else if (priv->reg_layout == CLK_REG_LAYOUT_RZ_A) {
1086 		priv->control_regs = stbcr;
1087 	} else if (priv->reg_layout == CLK_REG_LAYOUT_RCAR_GEN4) {
1088 		priv->status_regs = mstpsr_for_gen4;
1089 		priv->control_regs = mstpcr_for_gen4;
1090 		priv->reset_regs = srcr_for_gen4;
1091 		priv->reset_clear_regs = srstclr_for_gen4;
1092 	} else {
1093 		error = -EINVAL;
1094 		goto out_err;
1095 	}
1096 
1097 	for (i = 0; i < nclks; i++)
1098 		priv->clks[i] = ERR_PTR(-ENOENT);
1099 
1100 	error = cpg_mssr_reserved_init(priv, info);
1101 	if (error)
1102 		goto out_err;
1103 
1104 	error = of_clk_add_provider(np, cpg_mssr_clk_src_twocell_get, priv);
1105 	if (error)
1106 		goto reserve_err;
1107 
1108 	cpg_mssr_priv = priv;
1109 
1110 	return 0;
1111 
1112 reserve_err:
1113 	cpg_mssr_reserved_exit(priv);
1114 out_err:
1115 	if (priv->base)
1116 		iounmap(priv->base);
1117 	kfree(priv);
1118 
1119 	return error;
1120 }
1121 
1122 void __init cpg_mssr_early_init(struct device_node *np,
1123 				const struct cpg_mssr_info *info)
1124 {
1125 	int error;
1126 	int i;
1127 
1128 	error = cpg_mssr_common_init(NULL, np, info);
1129 	if (error)
1130 		return;
1131 
1132 	for (i = 0; i < info->num_early_core_clks; i++)
1133 		cpg_mssr_register_core_clk(&info->early_core_clks[i], info,
1134 					   cpg_mssr_priv);
1135 
1136 	for (i = 0; i < info->num_early_mod_clks; i++)
1137 		cpg_mssr_register_mod_clk(&info->early_mod_clks[i], info,
1138 					  cpg_mssr_priv);
1139 
1140 }
1141 
1142 static int __init cpg_mssr_probe(struct platform_device *pdev)
1143 {
1144 	struct device *dev = &pdev->dev;
1145 	struct device_node *np = dev->of_node;
1146 	const struct cpg_mssr_info *info;
1147 	struct cpg_mssr_priv *priv;
1148 	unsigned int i;
1149 	int error;
1150 
1151 	info = of_device_get_match_data(dev);
1152 
1153 	if (!cpg_mssr_priv) {
1154 		error = cpg_mssr_common_init(dev, dev->of_node, info);
1155 		if (error)
1156 			return error;
1157 	}
1158 
1159 	priv = cpg_mssr_priv;
1160 	priv->dev = dev;
1161 	dev_set_drvdata(dev, priv);
1162 
1163 	for (i = 0; i < info->num_core_clks; i++)
1164 		cpg_mssr_register_core_clk(&info->core_clks[i], info, priv);
1165 
1166 	for (i = 0; i < info->num_mod_clks; i++)
1167 		cpg_mssr_register_mod_clk(&info->mod_clks[i], info, priv);
1168 
1169 	error = devm_add_action_or_reset(dev,
1170 					 cpg_mssr_del_clk_provider,
1171 					 np);
1172 	if (error)
1173 		goto reserve_exit;
1174 
1175 	error = cpg_mssr_add_clk_domain(dev, info->core_pm_clks,
1176 					info->num_core_pm_clks);
1177 	if (error)
1178 		goto reserve_exit;
1179 
1180 	/* Reset Controller not supported for Standby Control SoCs */
1181 	if (priv->reg_layout == CLK_REG_LAYOUT_RZ_A)
1182 		goto reserve_exit;
1183 
1184 	error = cpg_mssr_reset_controller_register(priv);
1185 
1186 reserve_exit:
1187 	cpg_mssr_reserved_exit(priv);
1188 
1189 	return error;
1190 }
1191 
1192 static struct platform_driver cpg_mssr_driver = {
1193 	.driver		= {
1194 		.name	= "renesas-cpg-mssr",
1195 		.of_match_table = cpg_mssr_match,
1196 		.pm = DEV_PM_OPS,
1197 	},
1198 };
1199 
1200 static int __init cpg_mssr_init(void)
1201 {
1202 	return platform_driver_probe(&cpg_mssr_driver, cpg_mssr_probe);
1203 }
1204 
1205 subsys_initcall(cpg_mssr_init);
1206 
1207 void __init mssr_mod_nullify(struct mssr_mod_clk *mod_clks,
1208 			     unsigned int num_mod_clks,
1209 			     const unsigned int *clks, unsigned int n)
1210 {
1211 	unsigned int i, j;
1212 
1213 	for (i = 0, j = 0; i < num_mod_clks && j < n; i++)
1214 		if (mod_clks[i].id == clks[j]) {
1215 			mod_clks[i].name = NULL;
1216 			j++;
1217 		}
1218 }
1219 
1220 MODULE_DESCRIPTION("Renesas CPG/MSSR Driver");
1221