xref: /linux/drivers/clk/renesas/renesas-cpg-mssr.c (revision 78c3925c048c752334873f56c3a3d1c9d53e0416)
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 /*
44  * Module Standby and Software Reset register offets.
45  *
46  * If the registers exist, these are valid for SH-Mobile, R-Mobile,
47  * R-Car Gen2, R-Car Gen3, and RZ/G1.
48  * These are NOT valid for R-Car Gen1 and RZ/A1!
49  */
50 
51 /*
52  * Module Stop Status Register offsets
53  */
54 
55 static const u16 mstpsr[] = {
56 	0x030, 0x038, 0x040, 0x048, 0x04C, 0x03C, 0x1C0, 0x1C4,
57 	0x9A0, 0x9A4, 0x9A8, 0x9AC,
58 };
59 
60 static const u16 mstpsr_for_gen4[] = {
61 	0x2E00, 0x2E04, 0x2E08, 0x2E0C, 0x2E10, 0x2E14, 0x2E18, 0x2E1C,
62 	0x2E20, 0x2E24, 0x2E28, 0x2E2C, 0x2E30, 0x2E34, 0x2E38, 0x2E3C,
63 	0x2E40, 0x2E44, 0x2E48, 0x2E4C, 0x2E50, 0x2E54, 0x2E58, 0x2E5C,
64 	0x2E60, 0x2E64, 0x2E68, 0x2E6C, 0x2E70, 0x2E74,
65 };
66 
67 /*
68  * System Module Stop Control Register offsets
69  */
70 
71 static const u16 smstpcr[] = {
72 	0x130, 0x134, 0x138, 0x13C, 0x140, 0x144, 0x148, 0x14C,
73 	0x990, 0x994, 0x998, 0x99C,
74 };
75 
76 static const u16 mstpcr_for_gen4[] = {
77 	0x2D00, 0x2D04, 0x2D08, 0x2D0C, 0x2D10, 0x2D14, 0x2D18, 0x2D1C,
78 	0x2D20, 0x2D24, 0x2D28, 0x2D2C, 0x2D30, 0x2D34, 0x2D38, 0x2D3C,
79 	0x2D40, 0x2D44, 0x2D48, 0x2D4C, 0x2D50, 0x2D54, 0x2D58, 0x2D5C,
80 	0x2D60, 0x2D64, 0x2D68, 0x2D6C, 0x2D70, 0x2D74,
81 };
82 
83 /*
84  * Standby Control Register offsets (RZ/A)
85  * Base address is FRQCR register
86  */
87 
88 static const u16 stbcr[] = {
89 	0xFFFF/*dummy*/, 0x010, 0x014, 0x410, 0x414, 0x418, 0x41C, 0x420,
90 	0x424, 0x428, 0x42C,
91 };
92 
93 /*
94  * Software Reset Register offsets
95  */
96 
97 static const u16 srcr[] = {
98 	0x0A0, 0x0A8, 0x0B0, 0x0B8, 0x0BC, 0x0C4, 0x1C8, 0x1CC,
99 	0x920, 0x924, 0x928, 0x92C,
100 };
101 
102 static const u16 srcr_for_gen4[] = {
103 	0x2C00, 0x2C04, 0x2C08, 0x2C0C, 0x2C10, 0x2C14, 0x2C18, 0x2C1C,
104 	0x2C20, 0x2C24, 0x2C28, 0x2C2C, 0x2C30, 0x2C34, 0x2C38, 0x2C3C,
105 	0x2C40, 0x2C44, 0x2C48, 0x2C4C, 0x2C50, 0x2C54, 0x2C58, 0x2C5C,
106 	0x2C60, 0x2C64, 0x2C68, 0x2C6C, 0x2C70, 0x2C74,
107 };
108 
109 /*
110  * Software Reset Clearing Register offsets
111  */
112 
113 static const u16 srstclr[] = {
114 	0x940, 0x944, 0x948, 0x94C, 0x950, 0x954, 0x958, 0x95C,
115 	0x960, 0x964, 0x968, 0x96C,
116 };
117 
118 static const u16 srstclr_for_gen4[] = {
119 	0x2C80, 0x2C84, 0x2C88, 0x2C8C, 0x2C90, 0x2C94, 0x2C98, 0x2C9C,
120 	0x2CA0, 0x2CA4, 0x2CA8, 0x2CAC, 0x2CB0, 0x2CB4, 0x2CB8, 0x2CBC,
121 	0x2CC0, 0x2CC4, 0x2CC8, 0x2CCC, 0x2CD0, 0x2CD4, 0x2CD8, 0x2CDC,
122 	0x2CE0, 0x2CE4, 0x2CE8, 0x2CEC, 0x2CF0, 0x2CF4,
123 };
124 
125 /**
126  * struct cpg_mssr_priv - Clock Pulse Generator / Module Standby
127  *                        and Software Reset Private Data
128  *
129  * @rcdev: Optional reset controller entity
130  * @dev: CPG/MSSR device
131  * @base: CPG/MSSR register block base address
132  * @reg_layout: CPG/MSSR register layout
133  * @rmw_lock: protects RMW register accesses
134  * @np: Device node in DT for this CPG/MSSR module
135  * @num_core_clks: Number of Core Clocks in clks[]
136  * @num_mod_clks: Number of Module Clocks in clks[]
137  * @last_dt_core_clk: ID of the last Core Clock exported to DT
138  * @notifiers: Notifier chain to save/restore clock state for system resume
139  * @status_regs: Pointer to status registers array
140  * @control_regs: Pointer to control registers array
141  * @reset_regs: Pointer to reset registers array
142  * @reset_clear_regs:  Pointer to reset clearing registers array
143  * @smstpcr_saved: [].mask: Mask of SMSTPCR[] bits under our control
144  *                 [].val: Saved values of SMSTPCR[]
145  * @reserved_ids: Temporary used, reserved id list
146  * @num_reserved_ids: Temporary used, number of reserved id list
147  * @clks: Array containing all Core and Module Clocks
148  */
149 struct cpg_mssr_priv {
150 #ifdef CONFIG_RESET_CONTROLLER
151 	struct reset_controller_dev rcdev;
152 #endif
153 	struct device *dev;
154 	void __iomem *base;
155 	enum clk_reg_layout reg_layout;
156 	spinlock_t rmw_lock;
157 	struct device_node *np;
158 
159 	unsigned int num_core_clks;
160 	unsigned int num_mod_clks;
161 	unsigned int last_dt_core_clk;
162 
163 	struct raw_notifier_head notifiers;
164 	const u16 *status_regs;
165 	const u16 *control_regs;
166 	const u16 *reset_regs;
167 	const u16 *reset_clear_regs;
168 	struct {
169 		u32 mask;
170 		u32 val;
171 	} smstpcr_saved[ARRAY_SIZE(mstpsr_for_gen4)];
172 
173 	unsigned int *reserved_ids;
174 	unsigned int num_reserved_ids;
175 
176 	struct clk *clks[];
177 };
178 
179 static struct cpg_mssr_priv *cpg_mssr_priv;
180 
181 /**
182  * struct mstp_clock - MSTP gating clock
183  * @hw: handle between common and hardware-specific interfaces
184  * @index: MSTP clock number
185  * @priv: CPG/MSSR private data
186  */
187 struct mstp_clock {
188 	struct clk_hw hw;
189 	u32 index;
190 	struct cpg_mssr_priv *priv;
191 };
192 
193 #define to_mstp_clock(_hw) container_of(_hw, struct mstp_clock, hw)
194 
195 static int cpg_mstp_clock_endisable(struct clk_hw *hw, bool enable)
196 {
197 	struct mstp_clock *clock = to_mstp_clock(hw);
198 	struct cpg_mssr_priv *priv = clock->priv;
199 	unsigned int reg = clock->index / 32;
200 	unsigned int bit = clock->index % 32;
201 	struct device *dev = priv->dev;
202 	u32 bitmask = BIT(bit);
203 	unsigned long flags;
204 	u32 value;
205 	int error;
206 
207 	dev_dbg(dev, "MSTP %u%02u/%pC %s\n", reg, bit, hw->clk,
208 		enable ? "ON" : "OFF");
209 	spin_lock_irqsave(&priv->rmw_lock, flags);
210 
211 	if (priv->reg_layout == CLK_REG_LAYOUT_RZ_A) {
212 		value = readb(priv->base + priv->control_regs[reg]);
213 		if (enable)
214 			value &= ~bitmask;
215 		else
216 			value |= bitmask;
217 		writeb(value, priv->base + priv->control_regs[reg]);
218 
219 		/* dummy read to ensure write has completed */
220 		readb(priv->base + priv->control_regs[reg]);
221 		barrier_data(priv->base + priv->control_regs[reg]);
222 	} else {
223 		value = readl(priv->base + priv->control_regs[reg]);
224 		if (enable)
225 			value &= ~bitmask;
226 		else
227 			value |= bitmask;
228 		writel(value, priv->base + priv->control_regs[reg]);
229 	}
230 
231 	spin_unlock_irqrestore(&priv->rmw_lock, flags);
232 
233 	if (!enable || priv->reg_layout == CLK_REG_LAYOUT_RZ_A)
234 		return 0;
235 
236 	error = readl_poll_timeout_atomic(priv->base + priv->status_regs[reg],
237 					  value, !(value & bitmask), 0, 10);
238 	if (error)
239 		dev_err(dev, "Failed to enable SMSTP %p[%d]\n",
240 			priv->base + priv->control_regs[reg], bit);
241 
242 	return error;
243 }
244 
245 static int cpg_mstp_clock_enable(struct clk_hw *hw)
246 {
247 	return cpg_mstp_clock_endisable(hw, true);
248 }
249 
250 static void cpg_mstp_clock_disable(struct clk_hw *hw)
251 {
252 	cpg_mstp_clock_endisable(hw, false);
253 }
254 
255 static int cpg_mstp_clock_is_enabled(struct clk_hw *hw)
256 {
257 	struct mstp_clock *clock = to_mstp_clock(hw);
258 	struct cpg_mssr_priv *priv = clock->priv;
259 	u32 value;
260 
261 	if (priv->reg_layout == CLK_REG_LAYOUT_RZ_A)
262 		value = readb(priv->base + priv->control_regs[clock->index / 32]);
263 	else
264 		value = readl(priv->base + priv->status_regs[clock->index / 32]);
265 
266 	return !(value & BIT(clock->index % 32));
267 }
268 
269 static const struct clk_ops cpg_mstp_clock_ops = {
270 	.enable = cpg_mstp_clock_enable,
271 	.disable = cpg_mstp_clock_disable,
272 	.is_enabled = cpg_mstp_clock_is_enabled,
273 };
274 
275 static
276 struct clk *cpg_mssr_clk_src_twocell_get(struct of_phandle_args *clkspec,
277 					 void *data)
278 {
279 	unsigned int clkidx = clkspec->args[1];
280 	struct cpg_mssr_priv *priv = data;
281 	struct device *dev = priv->dev;
282 	unsigned int idx;
283 	const char *type;
284 	struct clk *clk;
285 	int range_check;
286 
287 	switch (clkspec->args[0]) {
288 	case CPG_CORE:
289 		type = "core";
290 		if (clkidx > priv->last_dt_core_clk) {
291 			dev_err(dev, "Invalid %s clock index %u\n", type,
292 			       clkidx);
293 			return ERR_PTR(-EINVAL);
294 		}
295 		clk = priv->clks[clkidx];
296 		break;
297 
298 	case CPG_MOD:
299 		type = "module";
300 		if (priv->reg_layout == CLK_REG_LAYOUT_RZ_A) {
301 			idx = MOD_CLK_PACK_10(clkidx);
302 			range_check = 7 - (clkidx % 10);
303 		} else {
304 			idx = MOD_CLK_PACK(clkidx);
305 			range_check = 31 - (clkidx % 100);
306 		}
307 		if (range_check < 0 || idx >= priv->num_mod_clks) {
308 			dev_err(dev, "Invalid %s clock index %u\n", type,
309 				clkidx);
310 			return ERR_PTR(-EINVAL);
311 		}
312 		clk = priv->clks[priv->num_core_clks + idx];
313 		break;
314 
315 	default:
316 		dev_err(dev, "Invalid CPG clock type %u\n", clkspec->args[0]);
317 		return ERR_PTR(-EINVAL);
318 	}
319 
320 	if (IS_ERR(clk))
321 		dev_err(dev, "Cannot get %s clock %u: %ld", type, clkidx,
322 		       PTR_ERR(clk));
323 	else
324 		dev_dbg(dev, "clock (%u, %u) is %pC at %lu Hz\n",
325 			clkspec->args[0], clkspec->args[1], clk,
326 			clk_get_rate(clk));
327 	return clk;
328 }
329 
330 static void __init cpg_mssr_register_core_clk(const struct cpg_core_clk *core,
331 					      const struct cpg_mssr_info *info,
332 					      struct cpg_mssr_priv *priv)
333 {
334 	struct clk *clk = ERR_PTR(-ENOTSUPP), *parent;
335 	struct device *dev = priv->dev;
336 	unsigned int id = core->id, div = core->div;
337 	const char *parent_name;
338 
339 	WARN_DEBUG(id >= priv->num_core_clks);
340 	WARN_DEBUG(PTR_ERR(priv->clks[id]) != -ENOENT);
341 
342 	if (!core->name) {
343 		/* Skip NULLified clock */
344 		return;
345 	}
346 
347 	switch (core->type) {
348 	case CLK_TYPE_IN:
349 		clk = of_clk_get_by_name(priv->np, core->name);
350 		break;
351 
352 	case CLK_TYPE_FF:
353 	case CLK_TYPE_DIV6P1:
354 	case CLK_TYPE_DIV6_RO:
355 		WARN_DEBUG(core->parent >= priv->num_core_clks);
356 		parent = priv->clks[core->parent];
357 		if (IS_ERR(parent)) {
358 			clk = parent;
359 			goto fail;
360 		}
361 
362 		parent_name = __clk_get_name(parent);
363 
364 		if (core->type == CLK_TYPE_DIV6_RO)
365 			/* Multiply with the DIV6 register value */
366 			div *= (readl(priv->base + core->offset) & 0x3f) + 1;
367 
368 		if (core->type == CLK_TYPE_DIV6P1) {
369 			clk = cpg_div6_register(core->name, 1, &parent_name,
370 						priv->base + core->offset,
371 						&priv->notifiers);
372 		} else {
373 			clk = clk_register_fixed_factor(NULL, core->name,
374 							parent_name, 0,
375 							core->mult, div);
376 		}
377 		break;
378 
379 	case CLK_TYPE_FR:
380 		clk = clk_register_fixed_rate(NULL, core->name, NULL, 0,
381 					      core->mult);
382 		break;
383 
384 	default:
385 		if (info->cpg_clk_register)
386 			clk = info->cpg_clk_register(dev, core, info,
387 						     priv->clks, priv->base,
388 						     &priv->notifiers);
389 		else
390 			dev_err(dev, "%s has unsupported core clock type %u\n",
391 				core->name, core->type);
392 		break;
393 	}
394 
395 	if (IS_ERR_OR_NULL(clk))
396 		goto fail;
397 
398 	dev_dbg(dev, "Core clock %pC at %lu Hz\n", clk, clk_get_rate(clk));
399 	priv->clks[id] = clk;
400 	return;
401 
402 fail:
403 	dev_err(dev, "Failed to register %s clock %s: %ld\n", "core",
404 		core->name, PTR_ERR(clk));
405 }
406 
407 static void __init cpg_mssr_register_mod_clk(const struct mssr_mod_clk *mod,
408 					     const struct cpg_mssr_info *info,
409 					     struct cpg_mssr_priv *priv)
410 {
411 	struct mstp_clock *clock = NULL;
412 	struct device *dev = priv->dev;
413 	unsigned int id = mod->id;
414 	struct clk_init_data init = {};
415 	struct clk *parent, *clk;
416 	const char *parent_name;
417 	unsigned int i;
418 
419 	WARN_DEBUG(id < priv->num_core_clks);
420 	WARN_DEBUG(id >= priv->num_core_clks + priv->num_mod_clks);
421 	WARN_DEBUG(mod->parent >= priv->num_core_clks + priv->num_mod_clks);
422 	WARN_DEBUG(PTR_ERR(priv->clks[id]) != -ENOENT);
423 
424 	if (!mod->name) {
425 		/* Skip NULLified clock */
426 		return;
427 	}
428 
429 	parent = priv->clks[mod->parent];
430 	if (IS_ERR(parent)) {
431 		clk = parent;
432 		goto fail;
433 	}
434 
435 	clock = kzalloc(sizeof(*clock), GFP_KERNEL);
436 	if (!clock) {
437 		clk = ERR_PTR(-ENOMEM);
438 		goto fail;
439 	}
440 
441 	init.name = mod->name;
442 	init.ops = &cpg_mstp_clock_ops;
443 	init.flags = CLK_SET_RATE_PARENT;
444 	parent_name = __clk_get_name(parent);
445 	init.parent_names = &parent_name;
446 	init.num_parents = 1;
447 
448 	clock->index = id - priv->num_core_clks;
449 	clock->priv = priv;
450 	clock->hw.init = &init;
451 
452 	for (i = 0; i < info->num_crit_mod_clks; i++)
453 		if (id == info->crit_mod_clks[i] &&
454 		    cpg_mstp_clock_is_enabled(&clock->hw)) {
455 			dev_dbg(dev, "MSTP %s setting CLK_IS_CRITICAL\n",
456 				mod->name);
457 			init.flags |= CLK_IS_CRITICAL;
458 			break;
459 		}
460 
461 	/*
462 	 * Ignore reserved device.
463 	 * see
464 	 *	cpg_mssr_reserved_init()
465 	 */
466 	for (i = 0; i < priv->num_reserved_ids; i++) {
467 		if (id == priv->reserved_ids[i]) {
468 			dev_info(dev, "Ignore Linux non-assigned mod (%s)\n", mod->name);
469 			init.flags |= CLK_IGNORE_UNUSED;
470 			break;
471 		}
472 	}
473 
474 	clk = clk_register(NULL, &clock->hw);
475 	if (IS_ERR(clk))
476 		goto fail;
477 
478 	dev_dbg(dev, "Module clock %pC at %lu Hz\n", clk, clk_get_rate(clk));
479 	priv->clks[id] = clk;
480 	priv->smstpcr_saved[clock->index / 32].mask |= BIT(clock->index % 32);
481 	return;
482 
483 fail:
484 	dev_err(dev, "Failed to register %s clock %s: %ld\n", "module",
485 		mod->name, PTR_ERR(clk));
486 	kfree(clock);
487 }
488 
489 struct cpg_mssr_clk_domain {
490 	struct generic_pm_domain genpd;
491 	unsigned int num_core_pm_clks;
492 	unsigned int core_pm_clks[];
493 };
494 
495 static struct cpg_mssr_clk_domain *cpg_mssr_clk_domain;
496 
497 static bool cpg_mssr_is_pm_clk(const struct of_phandle_args *clkspec,
498 			       struct cpg_mssr_clk_domain *pd)
499 {
500 	unsigned int i;
501 
502 	if (clkspec->np != pd->genpd.dev.of_node || clkspec->args_count != 2)
503 		return false;
504 
505 	switch (clkspec->args[0]) {
506 	case CPG_CORE:
507 		for (i = 0; i < pd->num_core_pm_clks; i++)
508 			if (clkspec->args[1] == pd->core_pm_clks[i])
509 				return true;
510 		return false;
511 
512 	case CPG_MOD:
513 		return true;
514 
515 	default:
516 		return false;
517 	}
518 }
519 
520 int cpg_mssr_attach_dev(struct generic_pm_domain *unused, struct device *dev)
521 {
522 	struct cpg_mssr_clk_domain *pd = cpg_mssr_clk_domain;
523 	struct device_node *np = dev->of_node;
524 	struct of_phandle_args clkspec;
525 	struct clk *clk;
526 	int i = 0;
527 	int error;
528 
529 	if (!pd) {
530 		dev_dbg(dev, "CPG/MSSR clock domain not yet available\n");
531 		return -EPROBE_DEFER;
532 	}
533 
534 	while (!of_parse_phandle_with_args(np, "clocks", "#clock-cells", i,
535 					   &clkspec)) {
536 		if (cpg_mssr_is_pm_clk(&clkspec, pd))
537 			goto found;
538 
539 		of_node_put(clkspec.np);
540 		i++;
541 	}
542 
543 	return 0;
544 
545 found:
546 	clk = of_clk_get_from_provider(&clkspec);
547 	of_node_put(clkspec.np);
548 
549 	if (IS_ERR(clk))
550 		return PTR_ERR(clk);
551 
552 	error = pm_clk_create(dev);
553 	if (error)
554 		goto fail_put;
555 
556 	error = pm_clk_add_clk(dev, clk);
557 	if (error)
558 		goto fail_destroy;
559 
560 	return 0;
561 
562 fail_destroy:
563 	pm_clk_destroy(dev);
564 fail_put:
565 	clk_put(clk);
566 	return error;
567 }
568 
569 void cpg_mssr_detach_dev(struct generic_pm_domain *unused, struct device *dev)
570 {
571 	if (!pm_clk_no_clocks(dev))
572 		pm_clk_destroy(dev);
573 }
574 
575 static void cpg_mssr_genpd_remove(void *data)
576 {
577 	pm_genpd_remove(data);
578 }
579 
580 static int __init cpg_mssr_add_clk_domain(struct device *dev,
581 					  const unsigned int *core_pm_clks,
582 					  unsigned int num_core_pm_clks)
583 {
584 	struct device_node *np = dev->of_node;
585 	struct generic_pm_domain *genpd;
586 	struct cpg_mssr_clk_domain *pd;
587 	size_t pm_size = num_core_pm_clks * sizeof(core_pm_clks[0]);
588 	int ret;
589 
590 	pd = devm_kzalloc(dev, sizeof(*pd) + pm_size, GFP_KERNEL);
591 	if (!pd)
592 		return -ENOMEM;
593 
594 	pd->num_core_pm_clks = num_core_pm_clks;
595 	memcpy(pd->core_pm_clks, core_pm_clks, pm_size);
596 
597 	genpd = &pd->genpd;
598 	genpd->name = np->name;
599 	genpd->flags = GENPD_FLAG_PM_CLK | GENPD_FLAG_ALWAYS_ON |
600 		       GENPD_FLAG_ACTIVE_WAKEUP;
601 	genpd->attach_dev = cpg_mssr_attach_dev;
602 	genpd->detach_dev = cpg_mssr_detach_dev;
603 	ret = pm_genpd_init(genpd, &pm_domain_always_on_gov, false);
604 	if (ret)
605 		return ret;
606 
607 	ret = devm_add_action_or_reset(dev, cpg_mssr_genpd_remove, genpd);
608 	if (ret)
609 		return ret;
610 
611 	cpg_mssr_clk_domain = pd;
612 
613 	return of_genpd_add_provider_simple(np, genpd);
614 }
615 
616 #ifdef CONFIG_RESET_CONTROLLER
617 
618 #define rcdev_to_priv(x)	container_of(x, struct cpg_mssr_priv, rcdev)
619 
620 static int cpg_mssr_reset(struct reset_controller_dev *rcdev,
621 			  unsigned long id)
622 {
623 	struct cpg_mssr_priv *priv = rcdev_to_priv(rcdev);
624 	unsigned int reg = id / 32;
625 	unsigned int bit = id % 32;
626 	u32 bitmask = BIT(bit);
627 
628 	dev_dbg(priv->dev, "reset %u%02u\n", reg, bit);
629 
630 	/* Reset module */
631 	writel(bitmask, priv->base + priv->reset_regs[reg]);
632 
633 	/* Wait for at least one cycle of the RCLK clock (@ ca. 32 kHz) */
634 	udelay(35);
635 
636 	/* Release module from reset state */
637 	writel(bitmask, priv->base + priv->reset_clear_regs[reg]);
638 
639 	return 0;
640 }
641 
642 static int cpg_mssr_assert(struct reset_controller_dev *rcdev, unsigned long id)
643 {
644 	struct cpg_mssr_priv *priv = rcdev_to_priv(rcdev);
645 	unsigned int reg = id / 32;
646 	unsigned int bit = id % 32;
647 	u32 bitmask = BIT(bit);
648 
649 	dev_dbg(priv->dev, "assert %u%02u\n", reg, bit);
650 
651 	writel(bitmask, priv->base + priv->reset_regs[reg]);
652 	return 0;
653 }
654 
655 static int cpg_mssr_deassert(struct reset_controller_dev *rcdev,
656 			     unsigned long id)
657 {
658 	struct cpg_mssr_priv *priv = rcdev_to_priv(rcdev);
659 	unsigned int reg = id / 32;
660 	unsigned int bit = id % 32;
661 	u32 bitmask = BIT(bit);
662 
663 	dev_dbg(priv->dev, "deassert %u%02u\n", reg, bit);
664 
665 	writel(bitmask, priv->base + priv->reset_clear_regs[reg]);
666 	return 0;
667 }
668 
669 static int cpg_mssr_status(struct reset_controller_dev *rcdev,
670 			   unsigned long id)
671 {
672 	struct cpg_mssr_priv *priv = rcdev_to_priv(rcdev);
673 	unsigned int reg = id / 32;
674 	unsigned int bit = id % 32;
675 	u32 bitmask = BIT(bit);
676 
677 	return !!(readl(priv->base + priv->reset_regs[reg]) & bitmask);
678 }
679 
680 static const struct reset_control_ops cpg_mssr_reset_ops = {
681 	.reset = cpg_mssr_reset,
682 	.assert = cpg_mssr_assert,
683 	.deassert = cpg_mssr_deassert,
684 	.status = cpg_mssr_status,
685 };
686 
687 static int cpg_mssr_reset_xlate(struct reset_controller_dev *rcdev,
688 				const struct of_phandle_args *reset_spec)
689 {
690 	struct cpg_mssr_priv *priv = rcdev_to_priv(rcdev);
691 	unsigned int unpacked = reset_spec->args[0];
692 	unsigned int idx = MOD_CLK_PACK(unpacked);
693 
694 	if (unpacked % 100 > 31 || idx >= rcdev->nr_resets) {
695 		dev_err(priv->dev, "Invalid reset index %u\n", unpacked);
696 		return -EINVAL;
697 	}
698 
699 	return idx;
700 }
701 
702 static int cpg_mssr_reset_controller_register(struct cpg_mssr_priv *priv)
703 {
704 	priv->rcdev.ops = &cpg_mssr_reset_ops;
705 	priv->rcdev.of_node = priv->dev->of_node;
706 	priv->rcdev.of_reset_n_cells = 1;
707 	priv->rcdev.of_xlate = cpg_mssr_reset_xlate;
708 	priv->rcdev.nr_resets = priv->num_mod_clks;
709 	return devm_reset_controller_register(priv->dev, &priv->rcdev);
710 }
711 
712 #else /* !CONFIG_RESET_CONTROLLER */
713 static inline int cpg_mssr_reset_controller_register(struct cpg_mssr_priv *priv)
714 {
715 	return 0;
716 }
717 #endif /* !CONFIG_RESET_CONTROLLER */
718 
719 
720 static const struct of_device_id cpg_mssr_match[] = {
721 #ifdef CONFIG_CLK_R7S9210
722 	{
723 		.compatible = "renesas,r7s9210-cpg-mssr",
724 		.data = &r7s9210_cpg_mssr_info,
725 	},
726 #endif
727 #ifdef CONFIG_CLK_R8A7742
728 	{
729 		.compatible = "renesas,r8a7742-cpg-mssr",
730 		.data = &r8a7742_cpg_mssr_info,
731 	},
732 #endif
733 #ifdef CONFIG_CLK_R8A7743
734 	{
735 		.compatible = "renesas,r8a7743-cpg-mssr",
736 		.data = &r8a7743_cpg_mssr_info,
737 	},
738 	/* RZ/G1N is (almost) identical to RZ/G1M w.r.t. clocks. */
739 	{
740 		.compatible = "renesas,r8a7744-cpg-mssr",
741 		.data = &r8a7743_cpg_mssr_info,
742 	},
743 #endif
744 #ifdef CONFIG_CLK_R8A7745
745 	{
746 		.compatible = "renesas,r8a7745-cpg-mssr",
747 		.data = &r8a7745_cpg_mssr_info,
748 	},
749 #endif
750 #ifdef CONFIG_CLK_R8A77470
751 	{
752 		.compatible = "renesas,r8a77470-cpg-mssr",
753 		.data = &r8a77470_cpg_mssr_info,
754 	},
755 #endif
756 #ifdef CONFIG_CLK_R8A774A1
757 	{
758 		.compatible = "renesas,r8a774a1-cpg-mssr",
759 		.data = &r8a774a1_cpg_mssr_info,
760 	},
761 #endif
762 #ifdef CONFIG_CLK_R8A774B1
763 	{
764 		.compatible = "renesas,r8a774b1-cpg-mssr",
765 		.data = &r8a774b1_cpg_mssr_info,
766 	},
767 #endif
768 #ifdef CONFIG_CLK_R8A774C0
769 	{
770 		.compatible = "renesas,r8a774c0-cpg-mssr",
771 		.data = &r8a774c0_cpg_mssr_info,
772 	},
773 #endif
774 #ifdef CONFIG_CLK_R8A774E1
775 	{
776 		.compatible = "renesas,r8a774e1-cpg-mssr",
777 		.data = &r8a774e1_cpg_mssr_info,
778 	},
779 #endif
780 #ifdef CONFIG_CLK_R8A7790
781 	{
782 		.compatible = "renesas,r8a7790-cpg-mssr",
783 		.data = &r8a7790_cpg_mssr_info,
784 	},
785 #endif
786 #ifdef CONFIG_CLK_R8A7791
787 	{
788 		.compatible = "renesas,r8a7791-cpg-mssr",
789 		.data = &r8a7791_cpg_mssr_info,
790 	},
791 	/* R-Car M2-N is (almost) identical to R-Car M2-W w.r.t. clocks. */
792 	{
793 		.compatible = "renesas,r8a7793-cpg-mssr",
794 		.data = &r8a7791_cpg_mssr_info,
795 	},
796 #endif
797 #ifdef CONFIG_CLK_R8A7792
798 	{
799 		.compatible = "renesas,r8a7792-cpg-mssr",
800 		.data = &r8a7792_cpg_mssr_info,
801 	},
802 #endif
803 #ifdef CONFIG_CLK_R8A7794
804 	{
805 		.compatible = "renesas,r8a7794-cpg-mssr",
806 		.data = &r8a7794_cpg_mssr_info,
807 	},
808 #endif
809 #ifdef CONFIG_CLK_R8A7795
810 	{
811 		.compatible = "renesas,r8a7795-cpg-mssr",
812 		.data = &r8a7795_cpg_mssr_info,
813 	},
814 #endif
815 #ifdef CONFIG_CLK_R8A77960
816 	{
817 		.compatible = "renesas,r8a7796-cpg-mssr",
818 		.data = &r8a7796_cpg_mssr_info,
819 	},
820 #endif
821 #ifdef CONFIG_CLK_R8A77961
822 	{
823 		.compatible = "renesas,r8a77961-cpg-mssr",
824 		.data = &r8a7796_cpg_mssr_info,
825 	},
826 #endif
827 #ifdef CONFIG_CLK_R8A77965
828 	{
829 		.compatible = "renesas,r8a77965-cpg-mssr",
830 		.data = &r8a77965_cpg_mssr_info,
831 	},
832 #endif
833 #ifdef CONFIG_CLK_R8A77970
834 	{
835 		.compatible = "renesas,r8a77970-cpg-mssr",
836 		.data = &r8a77970_cpg_mssr_info,
837 	},
838 #endif
839 #ifdef CONFIG_CLK_R8A77980
840 	{
841 		.compatible = "renesas,r8a77980-cpg-mssr",
842 		.data = &r8a77980_cpg_mssr_info,
843 	},
844 #endif
845 #ifdef CONFIG_CLK_R8A77990
846 	{
847 		.compatible = "renesas,r8a77990-cpg-mssr",
848 		.data = &r8a77990_cpg_mssr_info,
849 	},
850 #endif
851 #ifdef CONFIG_CLK_R8A77995
852 	{
853 		.compatible = "renesas,r8a77995-cpg-mssr",
854 		.data = &r8a77995_cpg_mssr_info,
855 	},
856 #endif
857 #ifdef CONFIG_CLK_R8A779A0
858 	{
859 		.compatible = "renesas,r8a779a0-cpg-mssr",
860 		.data = &r8a779a0_cpg_mssr_info,
861 	},
862 #endif
863 #ifdef CONFIG_CLK_R8A779F0
864 	{
865 		.compatible = "renesas,r8a779f0-cpg-mssr",
866 		.data = &r8a779f0_cpg_mssr_info,
867 	},
868 #endif
869 #ifdef CONFIG_CLK_R8A779G0
870 	{
871 		.compatible = "renesas,r8a779g0-cpg-mssr",
872 		.data = &r8a779g0_cpg_mssr_info,
873 	},
874 #endif
875 #ifdef CONFIG_CLK_R8A779H0
876 	{
877 		.compatible = "renesas,r8a779h0-cpg-mssr",
878 		.data = &r8a779h0_cpg_mssr_info,
879 	},
880 #endif
881 	{ /* sentinel */ }
882 };
883 
884 static void cpg_mssr_del_clk_provider(void *data)
885 {
886 	of_clk_del_provider(data);
887 }
888 
889 #if defined(CONFIG_PM_SLEEP) && defined(CONFIG_ARM_PSCI_FW)
890 static int cpg_mssr_suspend_noirq(struct device *dev)
891 {
892 	struct cpg_mssr_priv *priv = dev_get_drvdata(dev);
893 	unsigned int reg;
894 
895 	/* This is the best we can do to check for the presence of PSCI */
896 	if (!psci_ops.cpu_suspend)
897 		return 0;
898 
899 	/* Save module registers with bits under our control */
900 	for (reg = 0; reg < ARRAY_SIZE(priv->smstpcr_saved); reg++) {
901 		if (priv->smstpcr_saved[reg].mask)
902 			priv->smstpcr_saved[reg].val =
903 				priv->reg_layout == CLK_REG_LAYOUT_RZ_A ?
904 				readb(priv->base + priv->control_regs[reg]) :
905 				readl(priv->base + priv->control_regs[reg]);
906 	}
907 
908 	/* Save core clocks */
909 	raw_notifier_call_chain(&priv->notifiers, PM_EVENT_SUSPEND, NULL);
910 
911 	return 0;
912 }
913 
914 static int cpg_mssr_resume_noirq(struct device *dev)
915 {
916 	struct cpg_mssr_priv *priv = dev_get_drvdata(dev);
917 	unsigned int reg;
918 	u32 mask, oldval, newval;
919 	int error;
920 
921 	/* This is the best we can do to check for the presence of PSCI */
922 	if (!psci_ops.cpu_suspend)
923 		return 0;
924 
925 	/* Restore core clocks */
926 	raw_notifier_call_chain(&priv->notifiers, PM_EVENT_RESUME, NULL);
927 
928 	/* Restore module clocks */
929 	for (reg = 0; reg < ARRAY_SIZE(priv->smstpcr_saved); reg++) {
930 		mask = priv->smstpcr_saved[reg].mask;
931 		if (!mask)
932 			continue;
933 
934 		if (priv->reg_layout == CLK_REG_LAYOUT_RZ_A)
935 			oldval = readb(priv->base + priv->control_regs[reg]);
936 		else
937 			oldval = readl(priv->base + priv->control_regs[reg]);
938 		newval = oldval & ~mask;
939 		newval |= priv->smstpcr_saved[reg].val & mask;
940 		if (newval == oldval)
941 			continue;
942 
943 		if (priv->reg_layout == CLK_REG_LAYOUT_RZ_A) {
944 			writeb(newval, priv->base + priv->control_regs[reg]);
945 			/* dummy read to ensure write has completed */
946 			readb(priv->base + priv->control_regs[reg]);
947 			barrier_data(priv->base + priv->control_regs[reg]);
948 			continue;
949 		} else
950 			writel(newval, priv->base + priv->control_regs[reg]);
951 
952 		/* Wait until enabled clocks are really enabled */
953 		mask &= ~priv->smstpcr_saved[reg].val;
954 		if (!mask)
955 			continue;
956 
957 		error = readl_poll_timeout_atomic(priv->base + priv->status_regs[reg],
958 						oldval, !(oldval & mask), 0, 10);
959 		if (error)
960 			dev_warn(dev, "Failed to enable SMSTP%u[0x%x]\n", reg,
961 				 oldval & mask);
962 	}
963 
964 	return 0;
965 }
966 
967 static const struct dev_pm_ops cpg_mssr_pm = {
968 	SET_NOIRQ_SYSTEM_SLEEP_PM_OPS(cpg_mssr_suspend_noirq,
969 				      cpg_mssr_resume_noirq)
970 };
971 #define DEV_PM_OPS	&cpg_mssr_pm
972 #else
973 #define DEV_PM_OPS	NULL
974 #endif /* CONFIG_PM_SLEEP && CONFIG_ARM_PSCI_FW */
975 
976 static void __init cpg_mssr_reserved_exit(struct cpg_mssr_priv *priv)
977 {
978 	kfree(priv->reserved_ids);
979 }
980 
981 static int __init cpg_mssr_reserved_init(struct cpg_mssr_priv *priv,
982 					 const struct cpg_mssr_info *info)
983 {
984 	struct device_node *soc = of_find_node_by_path("/soc");
985 	struct device_node *node;
986 	uint32_t args[MAX_PHANDLE_ARGS];
987 	unsigned int *ids = NULL;
988 	unsigned int num = 0;
989 
990 	/*
991 	 * Because clk_disable_unused() will disable all unused clocks, the device which is assigned
992 	 * to a non-Linux system will be disabled when Linux is booted.
993 	 *
994 	 * To avoid such situation, renesas-cpg-mssr assumes the device which has
995 	 * status = "reserved" is assigned to a non-Linux system, and adds CLK_IGNORE_UNUSED flag
996 	 * to its CPG_MOD clocks.
997 	 * see also
998 	 *	cpg_mssr_register_mod_clk()
999 	 *
1000 	 *	scif5: serial@e6f30000 {
1001 	 *		...
1002 	 * =>		clocks = <&cpg CPG_MOD 202>,
1003 	 *			 <&cpg CPG_CORE R8A7795_CLK_S3D1>,
1004 	 *			 <&scif_clk>;
1005 	 *			 ...
1006 	 *		 status = "reserved";
1007 	 *	};
1008 	 */
1009 	for_each_reserved_child_of_node(soc, node) {
1010 		struct of_phandle_iterator it;
1011 		int rc;
1012 
1013 		of_for_each_phandle(&it, rc, node, "clocks", "#clock-cells", -1) {
1014 			int idx;
1015 
1016 			if (it.node != priv->np)
1017 				continue;
1018 
1019 			if (of_phandle_iterator_args(&it, args, MAX_PHANDLE_ARGS) != 2)
1020 				continue;
1021 
1022 			if (args[0] != CPG_MOD)
1023 				continue;
1024 
1025 			ids = krealloc_array(ids, (num + 1), sizeof(*ids), GFP_KERNEL);
1026 			if (!ids) {
1027 				of_node_put(it.node);
1028 				return -ENOMEM;
1029 			}
1030 
1031 			if (priv->reg_layout == CLK_REG_LAYOUT_RZ_A)
1032 				idx = MOD_CLK_PACK_10(args[1]);	/* for DEF_MOD_STB() */
1033 			else
1034 				idx = MOD_CLK_PACK(args[1]);	/* for DEF_MOD() */
1035 
1036 			ids[num] = info->num_total_core_clks + idx;
1037 
1038 			num++;
1039 		}
1040 	}
1041 
1042 	priv->num_reserved_ids	= num;
1043 	priv->reserved_ids	= ids;
1044 
1045 	return 0;
1046 }
1047 
1048 static int __init cpg_mssr_common_init(struct device *dev,
1049 				       struct device_node *np,
1050 				       const struct cpg_mssr_info *info)
1051 {
1052 	struct cpg_mssr_priv *priv;
1053 	unsigned int nclks, i;
1054 	int error;
1055 
1056 	if (info->init) {
1057 		error = info->init(dev);
1058 		if (error)
1059 			return error;
1060 	}
1061 
1062 	nclks = info->num_total_core_clks + info->num_hw_mod_clks;
1063 	priv = kzalloc(struct_size(priv, clks, nclks), GFP_KERNEL);
1064 	if (!priv)
1065 		return -ENOMEM;
1066 
1067 	priv->np = np;
1068 	priv->dev = dev;
1069 	spin_lock_init(&priv->rmw_lock);
1070 
1071 	priv->base = of_iomap(np, 0);
1072 	if (!priv->base) {
1073 		error = -ENOMEM;
1074 		goto out_err;
1075 	}
1076 
1077 	priv->num_core_clks = info->num_total_core_clks;
1078 	priv->num_mod_clks = info->num_hw_mod_clks;
1079 	priv->last_dt_core_clk = info->last_dt_core_clk;
1080 	RAW_INIT_NOTIFIER_HEAD(&priv->notifiers);
1081 	priv->reg_layout = info->reg_layout;
1082 	if (priv->reg_layout == CLK_REG_LAYOUT_RCAR_GEN2_AND_GEN3) {
1083 		priv->status_regs = mstpsr;
1084 		priv->control_regs = smstpcr;
1085 		priv->reset_regs = srcr;
1086 		priv->reset_clear_regs = srstclr;
1087 	} else if (priv->reg_layout == CLK_REG_LAYOUT_RZ_A) {
1088 		priv->control_regs = stbcr;
1089 	} else if (priv->reg_layout == CLK_REG_LAYOUT_RCAR_GEN4) {
1090 		priv->status_regs = mstpsr_for_gen4;
1091 		priv->control_regs = mstpcr_for_gen4;
1092 		priv->reset_regs = srcr_for_gen4;
1093 		priv->reset_clear_regs = srstclr_for_gen4;
1094 	} else {
1095 		error = -EINVAL;
1096 		goto out_err;
1097 	}
1098 
1099 	for (i = 0; i < nclks; i++)
1100 		priv->clks[i] = ERR_PTR(-ENOENT);
1101 
1102 	error = cpg_mssr_reserved_init(priv, info);
1103 	if (error)
1104 		goto out_err;
1105 
1106 	error = of_clk_add_provider(np, cpg_mssr_clk_src_twocell_get, priv);
1107 	if (error)
1108 		goto reserve_err;
1109 
1110 	cpg_mssr_priv = priv;
1111 
1112 	return 0;
1113 
1114 reserve_err:
1115 	cpg_mssr_reserved_exit(priv);
1116 out_err:
1117 	if (priv->base)
1118 		iounmap(priv->base);
1119 	kfree(priv);
1120 
1121 	return error;
1122 }
1123 
1124 void __init cpg_mssr_early_init(struct device_node *np,
1125 				const struct cpg_mssr_info *info)
1126 {
1127 	int error;
1128 	int i;
1129 
1130 	error = cpg_mssr_common_init(NULL, np, info);
1131 	if (error)
1132 		return;
1133 
1134 	for (i = 0; i < info->num_early_core_clks; i++)
1135 		cpg_mssr_register_core_clk(&info->early_core_clks[i], info,
1136 					   cpg_mssr_priv);
1137 
1138 	for (i = 0; i < info->num_early_mod_clks; i++)
1139 		cpg_mssr_register_mod_clk(&info->early_mod_clks[i], info,
1140 					  cpg_mssr_priv);
1141 
1142 }
1143 
1144 static int __init cpg_mssr_probe(struct platform_device *pdev)
1145 {
1146 	struct device *dev = &pdev->dev;
1147 	struct device_node *np = dev->of_node;
1148 	const struct cpg_mssr_info *info;
1149 	struct cpg_mssr_priv *priv;
1150 	unsigned int i;
1151 	int error;
1152 
1153 	info = of_device_get_match_data(dev);
1154 
1155 	if (!cpg_mssr_priv) {
1156 		error = cpg_mssr_common_init(dev, dev->of_node, info);
1157 		if (error)
1158 			return error;
1159 	}
1160 
1161 	priv = cpg_mssr_priv;
1162 	priv->dev = dev;
1163 	dev_set_drvdata(dev, priv);
1164 
1165 	for (i = 0; i < info->num_core_clks; i++)
1166 		cpg_mssr_register_core_clk(&info->core_clks[i], info, priv);
1167 
1168 	for (i = 0; i < info->num_mod_clks; i++)
1169 		cpg_mssr_register_mod_clk(&info->mod_clks[i], info, priv);
1170 
1171 	error = devm_add_action_or_reset(dev,
1172 					 cpg_mssr_del_clk_provider,
1173 					 np);
1174 	if (error)
1175 		goto reserve_exit;
1176 
1177 	error = cpg_mssr_add_clk_domain(dev, info->core_pm_clks,
1178 					info->num_core_pm_clks);
1179 	if (error)
1180 		goto reserve_exit;
1181 
1182 	/* Reset Controller not supported for Standby Control SoCs */
1183 	if (priv->reg_layout == CLK_REG_LAYOUT_RZ_A)
1184 		goto reserve_exit;
1185 
1186 	error = cpg_mssr_reset_controller_register(priv);
1187 
1188 reserve_exit:
1189 	cpg_mssr_reserved_exit(priv);
1190 
1191 	return error;
1192 }
1193 
1194 static struct platform_driver cpg_mssr_driver = {
1195 	.driver		= {
1196 		.name	= "renesas-cpg-mssr",
1197 		.of_match_table = cpg_mssr_match,
1198 		.pm = DEV_PM_OPS,
1199 	},
1200 };
1201 
1202 static int __init cpg_mssr_init(void)
1203 {
1204 	return platform_driver_probe(&cpg_mssr_driver, cpg_mssr_probe);
1205 }
1206 
1207 subsys_initcall(cpg_mssr_init);
1208 
1209 void __init mssr_mod_nullify(struct mssr_mod_clk *mod_clks,
1210 			     unsigned int num_mod_clks,
1211 			     const unsigned int *clks, unsigned int n)
1212 {
1213 	unsigned int i, j;
1214 
1215 	for (i = 0, j = 0; i < num_mod_clks && j < n; i++)
1216 		if (mod_clks[i].id == clks[j]) {
1217 			mod_clks[i].name = NULL;
1218 			j++;
1219 		}
1220 }
1221 
1222 MODULE_DESCRIPTION("Renesas CPG/MSSR Driver");
1223