xref: /linux/drivers/pmdomain/qcom/cpr.c (revision 55d0969c451159cff86949b38c39171cab962069)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Copyright (c) 2013-2015, The Linux Foundation. All rights reserved.
4  * Copyright (c) 2019, Linaro Limited
5  */
6 
7 #include <linux/cleanup.h>
8 #include <linux/module.h>
9 #include <linux/err.h>
10 #include <linux/debugfs.h>
11 #include <linux/string.h>
12 #include <linux/kernel.h>
13 #include <linux/list.h>
14 #include <linux/init.h>
15 #include <linux/io.h>
16 #include <linux/bitops.h>
17 #include <linux/slab.h>
18 #include <linux/of.h>
19 #include <linux/platform_device.h>
20 #include <linux/pm_domain.h>
21 #include <linux/pm_opp.h>
22 #include <linux/interrupt.h>
23 #include <linux/regmap.h>
24 #include <linux/mfd/syscon.h>
25 #include <linux/regulator/consumer.h>
26 #include <linux/clk.h>
27 #include <linux/nvmem-consumer.h>
28 
29 /* Register Offsets for RB-CPR and Bit Definitions */
30 
31 /* RBCPR Version Register */
32 #define REG_RBCPR_VERSION		0
33 #define RBCPR_VER_2			0x02
34 #define FLAGS_IGNORE_1ST_IRQ_STATUS	BIT(0)
35 
36 /* RBCPR Gate Count and Target Registers */
37 #define REG_RBCPR_GCNT_TARGET(n)	(0x60 + 4 * (n))
38 
39 #define RBCPR_GCNT_TARGET_TARGET_SHIFT	0
40 #define RBCPR_GCNT_TARGET_TARGET_MASK	GENMASK(11, 0)
41 #define RBCPR_GCNT_TARGET_GCNT_SHIFT	12
42 #define RBCPR_GCNT_TARGET_GCNT_MASK	GENMASK(9, 0)
43 
44 /* RBCPR Timer Control */
45 #define REG_RBCPR_TIMER_INTERVAL	0x44
46 #define REG_RBIF_TIMER_ADJUST		0x4c
47 
48 #define RBIF_TIMER_ADJ_CONS_UP_MASK	GENMASK(3, 0)
49 #define RBIF_TIMER_ADJ_CONS_UP_SHIFT	0
50 #define RBIF_TIMER_ADJ_CONS_DOWN_MASK	GENMASK(3, 0)
51 #define RBIF_TIMER_ADJ_CONS_DOWN_SHIFT	4
52 #define RBIF_TIMER_ADJ_CLAMP_INT_MASK	GENMASK(7, 0)
53 #define RBIF_TIMER_ADJ_CLAMP_INT_SHIFT	8
54 
55 /* RBCPR Config Register */
56 #define REG_RBIF_LIMIT			0x48
57 #define RBIF_LIMIT_CEILING_MASK		GENMASK(5, 0)
58 #define RBIF_LIMIT_CEILING_SHIFT	6
59 #define RBIF_LIMIT_FLOOR_BITS		6
60 #define RBIF_LIMIT_FLOOR_MASK		GENMASK(5, 0)
61 
62 #define RBIF_LIMIT_CEILING_DEFAULT	RBIF_LIMIT_CEILING_MASK
63 #define RBIF_LIMIT_FLOOR_DEFAULT	0
64 
65 #define REG_RBIF_SW_VLEVEL		0x94
66 #define RBIF_SW_VLEVEL_DEFAULT		0x20
67 
68 #define REG_RBCPR_STEP_QUOT		0x80
69 #define RBCPR_STEP_QUOT_STEPQUOT_MASK	GENMASK(7, 0)
70 #define RBCPR_STEP_QUOT_IDLE_CLK_MASK	GENMASK(3, 0)
71 #define RBCPR_STEP_QUOT_IDLE_CLK_SHIFT	8
72 
73 /* RBCPR Control Register */
74 #define REG_RBCPR_CTL			0x90
75 
76 #define RBCPR_CTL_LOOP_EN			BIT(0)
77 #define RBCPR_CTL_TIMER_EN			BIT(3)
78 #define RBCPR_CTL_SW_AUTO_CONT_ACK_EN		BIT(5)
79 #define RBCPR_CTL_SW_AUTO_CONT_NACK_DN_EN	BIT(6)
80 #define RBCPR_CTL_COUNT_MODE			BIT(10)
81 #define RBCPR_CTL_UP_THRESHOLD_MASK	GENMASK(3, 0)
82 #define RBCPR_CTL_UP_THRESHOLD_SHIFT	24
83 #define RBCPR_CTL_DN_THRESHOLD_MASK	GENMASK(3, 0)
84 #define RBCPR_CTL_DN_THRESHOLD_SHIFT	28
85 
86 /* RBCPR Ack/Nack Response */
87 #define REG_RBIF_CONT_ACK_CMD		0x98
88 #define REG_RBIF_CONT_NACK_CMD		0x9c
89 
90 /* RBCPR Result status Register */
91 #define REG_RBCPR_RESULT_0		0xa0
92 
93 #define RBCPR_RESULT0_BUSY_SHIFT	19
94 #define RBCPR_RESULT0_BUSY_MASK		BIT(RBCPR_RESULT0_BUSY_SHIFT)
95 #define RBCPR_RESULT0_ERROR_LT0_SHIFT	18
96 #define RBCPR_RESULT0_ERROR_SHIFT	6
97 #define RBCPR_RESULT0_ERROR_MASK	GENMASK(11, 0)
98 #define RBCPR_RESULT0_ERROR_STEPS_SHIFT	2
99 #define RBCPR_RESULT0_ERROR_STEPS_MASK	GENMASK(3, 0)
100 #define RBCPR_RESULT0_STEP_UP_SHIFT	1
101 
102 /* RBCPR Interrupt Control Register */
103 #define REG_RBIF_IRQ_EN(n)		(0x100 + 4 * (n))
104 #define REG_RBIF_IRQ_CLEAR		0x110
105 #define REG_RBIF_IRQ_STATUS		0x114
106 
107 #define CPR_INT_DONE		BIT(0)
108 #define CPR_INT_MIN		BIT(1)
109 #define CPR_INT_DOWN		BIT(2)
110 #define CPR_INT_MID		BIT(3)
111 #define CPR_INT_UP		BIT(4)
112 #define CPR_INT_MAX		BIT(5)
113 #define CPR_INT_CLAMP		BIT(6)
114 #define CPR_INT_ALL	(CPR_INT_DONE | CPR_INT_MIN | CPR_INT_DOWN | \
115 			CPR_INT_MID | CPR_INT_UP | CPR_INT_MAX | CPR_INT_CLAMP)
116 #define CPR_INT_DEFAULT	(CPR_INT_UP | CPR_INT_DOWN)
117 
118 #define CPR_NUM_RING_OSC	8
119 
120 /* CPR eFuse parameters */
121 #define CPR_FUSE_TARGET_QUOT_BITS_MASK	GENMASK(11, 0)
122 
123 #define CPR_FUSE_MIN_QUOT_DIFF		50
124 
125 #define FUSE_REVISION_UNKNOWN		(-1)
126 
127 enum voltage_change_dir {
128 	NO_CHANGE,
129 	DOWN,
130 	UP,
131 };
132 
133 struct cpr_fuse {
134 	char *ring_osc;
135 	char *init_voltage;
136 	char *quotient;
137 	char *quotient_offset;
138 };
139 
140 struct fuse_corner_data {
141 	int ref_uV;
142 	int max_uV;
143 	int min_uV;
144 	int max_volt_scale;
145 	int max_quot_scale;
146 	/* fuse quot */
147 	int quot_offset;
148 	int quot_scale;
149 	int quot_adjust;
150 	/* fuse quot_offset */
151 	int quot_offset_scale;
152 	int quot_offset_adjust;
153 };
154 
155 struct cpr_fuses {
156 	int init_voltage_step;
157 	int init_voltage_width;
158 	struct fuse_corner_data *fuse_corner_data;
159 };
160 
161 struct corner_data {
162 	unsigned int fuse_corner;
163 	unsigned long freq;
164 };
165 
166 struct cpr_desc {
167 	unsigned int num_fuse_corners;
168 	int min_diff_quot;
169 	int *step_quot;
170 
171 	unsigned int		timer_delay_us;
172 	unsigned int		timer_cons_up;
173 	unsigned int		timer_cons_down;
174 	unsigned int		up_threshold;
175 	unsigned int		down_threshold;
176 	unsigned int		idle_clocks;
177 	unsigned int		gcnt_us;
178 	unsigned int		vdd_apc_step_up_limit;
179 	unsigned int		vdd_apc_step_down_limit;
180 	unsigned int		clamp_timer_interval;
181 
182 	struct cpr_fuses cpr_fuses;
183 	bool reduce_to_fuse_uV;
184 	bool reduce_to_corner_uV;
185 };
186 
187 struct acc_desc {
188 	unsigned int	enable_reg;
189 	u32		enable_mask;
190 
191 	struct reg_sequence	*config;
192 	struct reg_sequence	*settings;
193 	int			num_regs_per_fuse;
194 };
195 
196 struct cpr_acc_desc {
197 	const struct cpr_desc *cpr_desc;
198 	const struct acc_desc *acc_desc;
199 };
200 
201 struct fuse_corner {
202 	int min_uV;
203 	int max_uV;
204 	int uV;
205 	int quot;
206 	int step_quot;
207 	const struct reg_sequence *accs;
208 	int num_accs;
209 	unsigned long max_freq;
210 	u8 ring_osc_idx;
211 };
212 
213 struct corner {
214 	int min_uV;
215 	int max_uV;
216 	int uV;
217 	int last_uV;
218 	int quot_adjust;
219 	u32 save_ctl;
220 	u32 save_irq;
221 	unsigned long freq;
222 	struct fuse_corner *fuse_corner;
223 };
224 
225 struct cpr_drv {
226 	unsigned int		num_corners;
227 	unsigned int		ref_clk_khz;
228 
229 	struct generic_pm_domain pd;
230 	struct device		*dev;
231 	struct device		*attached_cpu_dev;
232 	struct mutex		lock;
233 	void __iomem		*base;
234 	struct corner		*corner;
235 	struct regulator	*vdd_apc;
236 	struct clk		*cpu_clk;
237 	struct regmap		*tcsr;
238 	bool			loop_disabled;
239 	u32			gcnt;
240 	unsigned long		flags;
241 
242 	struct fuse_corner	*fuse_corners;
243 	struct corner		*corners;
244 
245 	const struct cpr_desc *desc;
246 	const struct acc_desc *acc_desc;
247 	const struct cpr_fuse *cpr_fuses;
248 
249 	struct dentry *debugfs;
250 };
251 
252 static bool cpr_is_allowed(struct cpr_drv *drv)
253 {
254 	return !drv->loop_disabled;
255 }
256 
257 static void cpr_write(struct cpr_drv *drv, u32 offset, u32 value)
258 {
259 	writel_relaxed(value, drv->base + offset);
260 }
261 
262 static u32 cpr_read(struct cpr_drv *drv, u32 offset)
263 {
264 	return readl_relaxed(drv->base + offset);
265 }
266 
267 static void
268 cpr_masked_write(struct cpr_drv *drv, u32 offset, u32 mask, u32 value)
269 {
270 	u32 val;
271 
272 	val = readl_relaxed(drv->base + offset);
273 	val &= ~mask;
274 	val |= value & mask;
275 	writel_relaxed(val, drv->base + offset);
276 }
277 
278 static void cpr_irq_clr(struct cpr_drv *drv)
279 {
280 	cpr_write(drv, REG_RBIF_IRQ_CLEAR, CPR_INT_ALL);
281 }
282 
283 static void cpr_irq_clr_nack(struct cpr_drv *drv)
284 {
285 	cpr_irq_clr(drv);
286 	cpr_write(drv, REG_RBIF_CONT_NACK_CMD, 1);
287 }
288 
289 static void cpr_irq_clr_ack(struct cpr_drv *drv)
290 {
291 	cpr_irq_clr(drv);
292 	cpr_write(drv, REG_RBIF_CONT_ACK_CMD, 1);
293 }
294 
295 static void cpr_irq_set(struct cpr_drv *drv, u32 int_bits)
296 {
297 	cpr_write(drv, REG_RBIF_IRQ_EN(0), int_bits);
298 }
299 
300 static void cpr_ctl_modify(struct cpr_drv *drv, u32 mask, u32 value)
301 {
302 	cpr_masked_write(drv, REG_RBCPR_CTL, mask, value);
303 }
304 
305 static void cpr_ctl_enable(struct cpr_drv *drv, struct corner *corner)
306 {
307 	u32 val, mask;
308 	const struct cpr_desc *desc = drv->desc;
309 
310 	/* Program Consecutive Up & Down */
311 	val = desc->timer_cons_down << RBIF_TIMER_ADJ_CONS_DOWN_SHIFT;
312 	val |= desc->timer_cons_up << RBIF_TIMER_ADJ_CONS_UP_SHIFT;
313 	mask = RBIF_TIMER_ADJ_CONS_UP_MASK | RBIF_TIMER_ADJ_CONS_DOWN_MASK;
314 	cpr_masked_write(drv, REG_RBIF_TIMER_ADJUST, mask, val);
315 	cpr_masked_write(drv, REG_RBCPR_CTL,
316 			 RBCPR_CTL_SW_AUTO_CONT_NACK_DN_EN |
317 			 RBCPR_CTL_SW_AUTO_CONT_ACK_EN,
318 			 corner->save_ctl);
319 	cpr_irq_set(drv, corner->save_irq);
320 
321 	if (cpr_is_allowed(drv) && corner->max_uV > corner->min_uV)
322 		val = RBCPR_CTL_LOOP_EN;
323 	else
324 		val = 0;
325 	cpr_ctl_modify(drv, RBCPR_CTL_LOOP_EN, val);
326 }
327 
328 static void cpr_ctl_disable(struct cpr_drv *drv)
329 {
330 	cpr_irq_set(drv, 0);
331 	cpr_ctl_modify(drv, RBCPR_CTL_SW_AUTO_CONT_NACK_DN_EN |
332 		       RBCPR_CTL_SW_AUTO_CONT_ACK_EN, 0);
333 	cpr_masked_write(drv, REG_RBIF_TIMER_ADJUST,
334 			 RBIF_TIMER_ADJ_CONS_UP_MASK |
335 			 RBIF_TIMER_ADJ_CONS_DOWN_MASK, 0);
336 	cpr_irq_clr(drv);
337 	cpr_write(drv, REG_RBIF_CONT_ACK_CMD, 1);
338 	cpr_write(drv, REG_RBIF_CONT_NACK_CMD, 1);
339 	cpr_ctl_modify(drv, RBCPR_CTL_LOOP_EN, 0);
340 }
341 
342 static bool cpr_ctl_is_enabled(struct cpr_drv *drv)
343 {
344 	u32 reg_val;
345 
346 	reg_val = cpr_read(drv, REG_RBCPR_CTL);
347 	return reg_val & RBCPR_CTL_LOOP_EN;
348 }
349 
350 static bool cpr_ctl_is_busy(struct cpr_drv *drv)
351 {
352 	u32 reg_val;
353 
354 	reg_val = cpr_read(drv, REG_RBCPR_RESULT_0);
355 	return reg_val & RBCPR_RESULT0_BUSY_MASK;
356 }
357 
358 static void cpr_corner_save(struct cpr_drv *drv, struct corner *corner)
359 {
360 	corner->save_ctl = cpr_read(drv, REG_RBCPR_CTL);
361 	corner->save_irq = cpr_read(drv, REG_RBIF_IRQ_EN(0));
362 }
363 
364 static void cpr_corner_restore(struct cpr_drv *drv, struct corner *corner)
365 {
366 	u32 gcnt, ctl, irq, ro_sel, step_quot;
367 	struct fuse_corner *fuse = corner->fuse_corner;
368 	const struct cpr_desc *desc = drv->desc;
369 	int i;
370 
371 	ro_sel = fuse->ring_osc_idx;
372 	gcnt = drv->gcnt;
373 	gcnt |= fuse->quot - corner->quot_adjust;
374 
375 	/* Program the step quotient and idle clocks */
376 	step_quot = desc->idle_clocks << RBCPR_STEP_QUOT_IDLE_CLK_SHIFT;
377 	step_quot |= fuse->step_quot & RBCPR_STEP_QUOT_STEPQUOT_MASK;
378 	cpr_write(drv, REG_RBCPR_STEP_QUOT, step_quot);
379 
380 	/* Clear the target quotient value and gate count of all ROs */
381 	for (i = 0; i < CPR_NUM_RING_OSC; i++)
382 		cpr_write(drv, REG_RBCPR_GCNT_TARGET(i), 0);
383 
384 	cpr_write(drv, REG_RBCPR_GCNT_TARGET(ro_sel), gcnt);
385 	ctl = corner->save_ctl;
386 	cpr_write(drv, REG_RBCPR_CTL, ctl);
387 	irq = corner->save_irq;
388 	cpr_irq_set(drv, irq);
389 	dev_dbg(drv->dev, "gcnt = %#08x, ctl = %#08x, irq = %#08x\n", gcnt,
390 		ctl, irq);
391 }
392 
393 static void cpr_set_acc(struct regmap *tcsr, struct fuse_corner *f,
394 			struct fuse_corner *end)
395 {
396 	if (f == end)
397 		return;
398 
399 	if (f < end) {
400 		for (f += 1; f <= end; f++)
401 			regmap_multi_reg_write(tcsr, f->accs, f->num_accs);
402 	} else {
403 		for (f -= 1; f >= end; f--)
404 			regmap_multi_reg_write(tcsr, f->accs, f->num_accs);
405 	}
406 }
407 
408 static int cpr_pre_voltage(struct cpr_drv *drv,
409 			   struct fuse_corner *fuse_corner,
410 			   enum voltage_change_dir dir)
411 {
412 	struct fuse_corner *prev_fuse_corner = drv->corner->fuse_corner;
413 
414 	if (drv->tcsr && dir == DOWN)
415 		cpr_set_acc(drv->tcsr, prev_fuse_corner, fuse_corner);
416 
417 	return 0;
418 }
419 
420 static int cpr_post_voltage(struct cpr_drv *drv,
421 			    struct fuse_corner *fuse_corner,
422 			    enum voltage_change_dir dir)
423 {
424 	struct fuse_corner *prev_fuse_corner = drv->corner->fuse_corner;
425 
426 	if (drv->tcsr && dir == UP)
427 		cpr_set_acc(drv->tcsr, prev_fuse_corner, fuse_corner);
428 
429 	return 0;
430 }
431 
432 static int cpr_scale_voltage(struct cpr_drv *drv, struct corner *corner,
433 			     int new_uV, enum voltage_change_dir dir)
434 {
435 	int ret;
436 	struct fuse_corner *fuse_corner = corner->fuse_corner;
437 
438 	ret = cpr_pre_voltage(drv, fuse_corner, dir);
439 	if (ret)
440 		return ret;
441 
442 	ret = regulator_set_voltage(drv->vdd_apc, new_uV, new_uV);
443 	if (ret) {
444 		dev_err_ratelimited(drv->dev, "failed to set apc voltage %d\n",
445 				    new_uV);
446 		return ret;
447 	}
448 
449 	ret = cpr_post_voltage(drv, fuse_corner, dir);
450 	if (ret)
451 		return ret;
452 
453 	return 0;
454 }
455 
456 static unsigned int cpr_get_cur_perf_state(struct cpr_drv *drv)
457 {
458 	return drv->corner ? drv->corner - drv->corners + 1 : 0;
459 }
460 
461 static int cpr_scale(struct cpr_drv *drv, enum voltage_change_dir dir)
462 {
463 	u32 val, error_steps, reg_mask;
464 	int last_uV, new_uV, step_uV, ret;
465 	struct corner *corner;
466 	const struct cpr_desc *desc = drv->desc;
467 
468 	if (dir != UP && dir != DOWN)
469 		return 0;
470 
471 	step_uV = regulator_get_linear_step(drv->vdd_apc);
472 	if (!step_uV)
473 		return -EINVAL;
474 
475 	corner = drv->corner;
476 
477 	val = cpr_read(drv, REG_RBCPR_RESULT_0);
478 
479 	error_steps = val >> RBCPR_RESULT0_ERROR_STEPS_SHIFT;
480 	error_steps &= RBCPR_RESULT0_ERROR_STEPS_MASK;
481 	last_uV = corner->last_uV;
482 
483 	if (dir == UP) {
484 		if (desc->clamp_timer_interval &&
485 		    error_steps < desc->up_threshold) {
486 			/*
487 			 * Handle the case where another measurement started
488 			 * after the interrupt was triggered due to a core
489 			 * exiting from power collapse.
490 			 */
491 			error_steps = max(desc->up_threshold,
492 					  desc->vdd_apc_step_up_limit);
493 		}
494 
495 		if (last_uV >= corner->max_uV) {
496 			cpr_irq_clr_nack(drv);
497 
498 			/* Maximize the UP threshold */
499 			reg_mask = RBCPR_CTL_UP_THRESHOLD_MASK;
500 			reg_mask <<= RBCPR_CTL_UP_THRESHOLD_SHIFT;
501 			val = reg_mask;
502 			cpr_ctl_modify(drv, reg_mask, val);
503 
504 			/* Disable UP interrupt */
505 			cpr_irq_set(drv, CPR_INT_DEFAULT & ~CPR_INT_UP);
506 
507 			return 0;
508 		}
509 
510 		if (error_steps > desc->vdd_apc_step_up_limit)
511 			error_steps = desc->vdd_apc_step_up_limit;
512 
513 		/* Calculate new voltage */
514 		new_uV = last_uV + error_steps * step_uV;
515 		new_uV = min(new_uV, corner->max_uV);
516 
517 		dev_dbg(drv->dev,
518 			"UP: -> new_uV: %d last_uV: %d perf state: %u\n",
519 			new_uV, last_uV, cpr_get_cur_perf_state(drv));
520 	} else {
521 		if (desc->clamp_timer_interval &&
522 		    error_steps < desc->down_threshold) {
523 			/*
524 			 * Handle the case where another measurement started
525 			 * after the interrupt was triggered due to a core
526 			 * exiting from power collapse.
527 			 */
528 			error_steps = max(desc->down_threshold,
529 					  desc->vdd_apc_step_down_limit);
530 		}
531 
532 		if (last_uV <= corner->min_uV) {
533 			cpr_irq_clr_nack(drv);
534 
535 			/* Enable auto nack down */
536 			reg_mask = RBCPR_CTL_SW_AUTO_CONT_NACK_DN_EN;
537 			val = RBCPR_CTL_SW_AUTO_CONT_NACK_DN_EN;
538 
539 			cpr_ctl_modify(drv, reg_mask, val);
540 
541 			/* Disable DOWN interrupt */
542 			cpr_irq_set(drv, CPR_INT_DEFAULT & ~CPR_INT_DOWN);
543 
544 			return 0;
545 		}
546 
547 		if (error_steps > desc->vdd_apc_step_down_limit)
548 			error_steps = desc->vdd_apc_step_down_limit;
549 
550 		/* Calculate new voltage */
551 		new_uV = last_uV - error_steps * step_uV;
552 		new_uV = max(new_uV, corner->min_uV);
553 
554 		dev_dbg(drv->dev,
555 			"DOWN: -> new_uV: %d last_uV: %d perf state: %u\n",
556 			new_uV, last_uV, cpr_get_cur_perf_state(drv));
557 	}
558 
559 	ret = cpr_scale_voltage(drv, corner, new_uV, dir);
560 	if (ret) {
561 		cpr_irq_clr_nack(drv);
562 		return ret;
563 	}
564 	drv->corner->last_uV = new_uV;
565 
566 	if (dir == UP) {
567 		/* Disable auto nack down */
568 		reg_mask = RBCPR_CTL_SW_AUTO_CONT_NACK_DN_EN;
569 		val = 0;
570 	} else {
571 		/* Restore default threshold for UP */
572 		reg_mask = RBCPR_CTL_UP_THRESHOLD_MASK;
573 		reg_mask <<= RBCPR_CTL_UP_THRESHOLD_SHIFT;
574 		val = desc->up_threshold;
575 		val <<= RBCPR_CTL_UP_THRESHOLD_SHIFT;
576 	}
577 
578 	cpr_ctl_modify(drv, reg_mask, val);
579 
580 	/* Re-enable default interrupts */
581 	cpr_irq_set(drv, CPR_INT_DEFAULT);
582 
583 	/* Ack */
584 	cpr_irq_clr_ack(drv);
585 
586 	return 0;
587 }
588 
589 static irqreturn_t cpr_irq_handler(int irq, void *dev)
590 {
591 	struct cpr_drv *drv = dev;
592 	const struct cpr_desc *desc = drv->desc;
593 	irqreturn_t ret = IRQ_HANDLED;
594 	u32 val;
595 
596 	mutex_lock(&drv->lock);
597 
598 	val = cpr_read(drv, REG_RBIF_IRQ_STATUS);
599 	if (drv->flags & FLAGS_IGNORE_1ST_IRQ_STATUS)
600 		val = cpr_read(drv, REG_RBIF_IRQ_STATUS);
601 
602 	dev_dbg(drv->dev, "IRQ_STATUS = %#02x\n", val);
603 
604 	if (!cpr_ctl_is_enabled(drv)) {
605 		dev_dbg(drv->dev, "CPR is disabled\n");
606 		ret = IRQ_NONE;
607 	} else if (cpr_ctl_is_busy(drv) && !desc->clamp_timer_interval) {
608 		dev_dbg(drv->dev, "CPR measurement is not ready\n");
609 	} else if (!cpr_is_allowed(drv)) {
610 		val = cpr_read(drv, REG_RBCPR_CTL);
611 		dev_err_ratelimited(drv->dev,
612 				    "Interrupt broken? RBCPR_CTL = %#02x\n",
613 				    val);
614 		ret = IRQ_NONE;
615 	} else {
616 		/*
617 		 * Following sequence of handling is as per each IRQ's
618 		 * priority
619 		 */
620 		if (val & CPR_INT_UP) {
621 			cpr_scale(drv, UP);
622 		} else if (val & CPR_INT_DOWN) {
623 			cpr_scale(drv, DOWN);
624 		} else if (val & CPR_INT_MIN) {
625 			cpr_irq_clr_nack(drv);
626 		} else if (val & CPR_INT_MAX) {
627 			cpr_irq_clr_nack(drv);
628 		} else if (val & CPR_INT_MID) {
629 			/* RBCPR_CTL_SW_AUTO_CONT_ACK_EN is enabled */
630 			dev_dbg(drv->dev, "IRQ occurred for Mid Flag\n");
631 		} else {
632 			dev_dbg(drv->dev,
633 				"IRQ occurred for unknown flag (%#08x)\n", val);
634 		}
635 
636 		/* Save register values for the corner */
637 		cpr_corner_save(drv, drv->corner);
638 	}
639 
640 	mutex_unlock(&drv->lock);
641 
642 	return ret;
643 }
644 
645 static int cpr_enable(struct cpr_drv *drv)
646 {
647 	int ret;
648 
649 	ret = regulator_enable(drv->vdd_apc);
650 	if (ret)
651 		return ret;
652 
653 	mutex_lock(&drv->lock);
654 
655 	if (cpr_is_allowed(drv) && drv->corner) {
656 		cpr_irq_clr(drv);
657 		cpr_corner_restore(drv, drv->corner);
658 		cpr_ctl_enable(drv, drv->corner);
659 	}
660 
661 	mutex_unlock(&drv->lock);
662 
663 	return 0;
664 }
665 
666 static int cpr_disable(struct cpr_drv *drv)
667 {
668 	mutex_lock(&drv->lock);
669 
670 	if (cpr_is_allowed(drv)) {
671 		cpr_ctl_disable(drv);
672 		cpr_irq_clr(drv);
673 	}
674 
675 	mutex_unlock(&drv->lock);
676 
677 	return regulator_disable(drv->vdd_apc);
678 }
679 
680 static int cpr_config(struct cpr_drv *drv)
681 {
682 	int i;
683 	u32 val, gcnt;
684 	struct corner *corner;
685 	const struct cpr_desc *desc = drv->desc;
686 
687 	/* Disable interrupt and CPR */
688 	cpr_write(drv, REG_RBIF_IRQ_EN(0), 0);
689 	cpr_write(drv, REG_RBCPR_CTL, 0);
690 
691 	/* Program the default HW ceiling, floor and vlevel */
692 	val = (RBIF_LIMIT_CEILING_DEFAULT & RBIF_LIMIT_CEILING_MASK)
693 		<< RBIF_LIMIT_CEILING_SHIFT;
694 	val |= RBIF_LIMIT_FLOOR_DEFAULT & RBIF_LIMIT_FLOOR_MASK;
695 	cpr_write(drv, REG_RBIF_LIMIT, val);
696 	cpr_write(drv, REG_RBIF_SW_VLEVEL, RBIF_SW_VLEVEL_DEFAULT);
697 
698 	/*
699 	 * Clear the target quotient value and gate count of all
700 	 * ring oscillators
701 	 */
702 	for (i = 0; i < CPR_NUM_RING_OSC; i++)
703 		cpr_write(drv, REG_RBCPR_GCNT_TARGET(i), 0);
704 
705 	/* Init and save gcnt */
706 	gcnt = (drv->ref_clk_khz * desc->gcnt_us) / 1000;
707 	gcnt = gcnt & RBCPR_GCNT_TARGET_GCNT_MASK;
708 	gcnt <<= RBCPR_GCNT_TARGET_GCNT_SHIFT;
709 	drv->gcnt = gcnt;
710 
711 	/* Program the delay count for the timer */
712 	val = (drv->ref_clk_khz * desc->timer_delay_us) / 1000;
713 	cpr_write(drv, REG_RBCPR_TIMER_INTERVAL, val);
714 	dev_dbg(drv->dev, "Timer count: %#0x (for %d us)\n", val,
715 		desc->timer_delay_us);
716 
717 	/* Program Consecutive Up & Down */
718 	val = desc->timer_cons_down << RBIF_TIMER_ADJ_CONS_DOWN_SHIFT;
719 	val |= desc->timer_cons_up << RBIF_TIMER_ADJ_CONS_UP_SHIFT;
720 	val |= desc->clamp_timer_interval << RBIF_TIMER_ADJ_CLAMP_INT_SHIFT;
721 	cpr_write(drv, REG_RBIF_TIMER_ADJUST, val);
722 
723 	/* Program the control register */
724 	val = desc->up_threshold << RBCPR_CTL_UP_THRESHOLD_SHIFT;
725 	val |= desc->down_threshold << RBCPR_CTL_DN_THRESHOLD_SHIFT;
726 	val |= RBCPR_CTL_TIMER_EN | RBCPR_CTL_COUNT_MODE;
727 	val |= RBCPR_CTL_SW_AUTO_CONT_ACK_EN;
728 	cpr_write(drv, REG_RBCPR_CTL, val);
729 
730 	for (i = 0; i < drv->num_corners; i++) {
731 		corner = &drv->corners[i];
732 		corner->save_ctl = val;
733 		corner->save_irq = CPR_INT_DEFAULT;
734 	}
735 
736 	cpr_irq_set(drv, CPR_INT_DEFAULT);
737 
738 	val = cpr_read(drv, REG_RBCPR_VERSION);
739 	if (val <= RBCPR_VER_2)
740 		drv->flags |= FLAGS_IGNORE_1ST_IRQ_STATUS;
741 
742 	return 0;
743 }
744 
745 static int cpr_set_performance_state(struct generic_pm_domain *domain,
746 				     unsigned int state)
747 {
748 	struct cpr_drv *drv = container_of(domain, struct cpr_drv, pd);
749 	struct corner *corner, *end;
750 	enum voltage_change_dir dir;
751 	int ret, new_uV;
752 
753 	guard(mutex)(&drv->lock);
754 
755 	dev_dbg(drv->dev, "%s: setting perf state: %u (prev state: %u)\n",
756 		__func__, state, cpr_get_cur_perf_state(drv));
757 
758 	/*
759 	 * Determine new corner we're going to.
760 	 * Remove one since lowest performance state is 1.
761 	 */
762 	corner = drv->corners + state - 1;
763 	end = &drv->corners[drv->num_corners - 1];
764 	if (corner > end || corner < drv->corners)
765 		return -EINVAL;
766 
767 	/* Determine direction */
768 	if (drv->corner > corner)
769 		dir = DOWN;
770 	else if (drv->corner < corner)
771 		dir = UP;
772 	else
773 		dir = NO_CHANGE;
774 
775 	if (cpr_is_allowed(drv))
776 		new_uV = corner->last_uV;
777 	else
778 		new_uV = corner->uV;
779 
780 	if (cpr_is_allowed(drv))
781 		cpr_ctl_disable(drv);
782 
783 	ret = cpr_scale_voltage(drv, corner, new_uV, dir);
784 	if (ret)
785 		return ret;
786 
787 	if (cpr_is_allowed(drv)) {
788 		cpr_irq_clr(drv);
789 		if (drv->corner != corner)
790 			cpr_corner_restore(drv, corner);
791 		cpr_ctl_enable(drv, corner);
792 	}
793 
794 	drv->corner = corner;
795 
796 	return 0;
797 }
798 
799 static int
800 cpr_populate_ring_osc_idx(struct cpr_drv *drv)
801 {
802 	struct fuse_corner *fuse = drv->fuse_corners;
803 	struct fuse_corner *end = fuse + drv->desc->num_fuse_corners;
804 	const struct cpr_fuse *fuses = drv->cpr_fuses;
805 	u32 data;
806 	int ret;
807 
808 	for (; fuse < end; fuse++, fuses++) {
809 		ret = nvmem_cell_read_variable_le_u32(drv->dev, fuses->ring_osc, &data);
810 		if (ret)
811 			return ret;
812 		fuse->ring_osc_idx = data;
813 	}
814 
815 	return 0;
816 }
817 
818 static int cpr_read_fuse_uV(const struct cpr_desc *desc,
819 			    const struct fuse_corner_data *fdata,
820 			    const char *init_v_efuse,
821 			    int step_volt,
822 			    struct cpr_drv *drv)
823 {
824 	int step_size_uV, steps, uV;
825 	u32 bits = 0;
826 	int ret;
827 
828 	ret = nvmem_cell_read_variable_le_u32(drv->dev, init_v_efuse, &bits);
829 	if (ret)
830 		return ret;
831 
832 	steps = bits & ~BIT(desc->cpr_fuses.init_voltage_width - 1);
833 	/* Not two's complement.. instead highest bit is sign bit */
834 	if (bits & BIT(desc->cpr_fuses.init_voltage_width - 1))
835 		steps = -steps;
836 
837 	step_size_uV = desc->cpr_fuses.init_voltage_step;
838 
839 	uV = fdata->ref_uV + steps * step_size_uV;
840 	return DIV_ROUND_UP(uV, step_volt) * step_volt;
841 }
842 
843 static int cpr_fuse_corner_init(struct cpr_drv *drv)
844 {
845 	const struct cpr_desc *desc = drv->desc;
846 	const struct cpr_fuse *fuses = drv->cpr_fuses;
847 	const struct acc_desc *acc_desc = drv->acc_desc;
848 	int i;
849 	unsigned int step_volt;
850 	struct fuse_corner_data *fdata;
851 	struct fuse_corner *fuse, *end;
852 	int uV;
853 	const struct reg_sequence *accs;
854 	int ret;
855 
856 	accs = acc_desc->settings;
857 
858 	step_volt = regulator_get_linear_step(drv->vdd_apc);
859 	if (!step_volt)
860 		return -EINVAL;
861 
862 	/* Populate fuse_corner members */
863 	fuse = drv->fuse_corners;
864 	end = &fuse[desc->num_fuse_corners - 1];
865 	fdata = desc->cpr_fuses.fuse_corner_data;
866 
867 	for (i = 0; fuse <= end; fuse++, fuses++, i++, fdata++) {
868 		/*
869 		 * Update SoC voltages: platforms might choose a different
870 		 * regulators than the one used to characterize the algorithms
871 		 * (ie, init_voltage_step).
872 		 */
873 		fdata->min_uV = roundup(fdata->min_uV, step_volt);
874 		fdata->max_uV = roundup(fdata->max_uV, step_volt);
875 
876 		/* Populate uV */
877 		uV = cpr_read_fuse_uV(desc, fdata, fuses->init_voltage,
878 				      step_volt, drv);
879 		if (uV < 0)
880 			return uV;
881 
882 		fuse->min_uV = fdata->min_uV;
883 		fuse->max_uV = fdata->max_uV;
884 		fuse->uV = clamp(uV, fuse->min_uV, fuse->max_uV);
885 
886 		if (fuse == end) {
887 			/*
888 			 * Allow the highest fuse corner's PVS voltage to
889 			 * define the ceiling voltage for that corner in order
890 			 * to support SoC's in which variable ceiling values
891 			 * are required.
892 			 */
893 			end->max_uV = max(end->max_uV, end->uV);
894 		}
895 
896 		/* Populate target quotient by scaling */
897 		ret = nvmem_cell_read_variable_le_u32(drv->dev, fuses->quotient, &fuse->quot);
898 		if (ret)
899 			return ret;
900 
901 		fuse->quot *= fdata->quot_scale;
902 		fuse->quot += fdata->quot_offset;
903 		fuse->quot += fdata->quot_adjust;
904 		fuse->step_quot = desc->step_quot[fuse->ring_osc_idx];
905 
906 		/* Populate acc settings */
907 		fuse->accs = accs;
908 		fuse->num_accs = acc_desc->num_regs_per_fuse;
909 		accs += acc_desc->num_regs_per_fuse;
910 	}
911 
912 	/*
913 	 * Restrict all fuse corner PVS voltages based upon per corner
914 	 * ceiling and floor voltages.
915 	 */
916 	for (fuse = drv->fuse_corners, i = 0; fuse <= end; fuse++, i++) {
917 		if (fuse->uV > fuse->max_uV)
918 			fuse->uV = fuse->max_uV;
919 		else if (fuse->uV < fuse->min_uV)
920 			fuse->uV = fuse->min_uV;
921 
922 		ret = regulator_is_supported_voltage(drv->vdd_apc,
923 						     fuse->min_uV,
924 						     fuse->min_uV);
925 		if (!ret) {
926 			dev_err(drv->dev,
927 				"min uV: %d (fuse corner: %d) not supported by regulator\n",
928 				fuse->min_uV, i);
929 			return -EINVAL;
930 		}
931 
932 		ret = regulator_is_supported_voltage(drv->vdd_apc,
933 						     fuse->max_uV,
934 						     fuse->max_uV);
935 		if (!ret) {
936 			dev_err(drv->dev,
937 				"max uV: %d (fuse corner: %d) not supported by regulator\n",
938 				fuse->max_uV, i);
939 			return -EINVAL;
940 		}
941 
942 		dev_dbg(drv->dev,
943 			"fuse corner %d: [%d %d %d] RO%hhu quot %d squot %d\n",
944 			i, fuse->min_uV, fuse->uV, fuse->max_uV,
945 			fuse->ring_osc_idx, fuse->quot, fuse->step_quot);
946 	}
947 
948 	return 0;
949 }
950 
951 static int cpr_calculate_scaling(const char *quot_offset,
952 				 struct cpr_drv *drv,
953 				 const struct fuse_corner_data *fdata,
954 				 const struct corner *corner)
955 {
956 	u32 quot_diff = 0;
957 	unsigned long freq_diff;
958 	int scaling;
959 	const struct fuse_corner *fuse, *prev_fuse;
960 	int ret;
961 
962 	fuse = corner->fuse_corner;
963 	prev_fuse = fuse - 1;
964 
965 	if (quot_offset) {
966 		ret = nvmem_cell_read_variable_le_u32(drv->dev, quot_offset, &quot_diff);
967 		if (ret)
968 			return ret;
969 
970 		quot_diff *= fdata->quot_offset_scale;
971 		quot_diff += fdata->quot_offset_adjust;
972 	} else {
973 		quot_diff = fuse->quot - prev_fuse->quot;
974 	}
975 
976 	freq_diff = fuse->max_freq - prev_fuse->max_freq;
977 	freq_diff /= 1000000; /* Convert to MHz */
978 	scaling = 1000 * quot_diff / freq_diff;
979 	return min(scaling, fdata->max_quot_scale);
980 }
981 
982 static int cpr_interpolate(const struct corner *corner, int step_volt,
983 			   const struct fuse_corner_data *fdata)
984 {
985 	unsigned long f_high, f_low, f_diff;
986 	int uV_high, uV_low, uV;
987 	u64 temp, temp_limit;
988 	const struct fuse_corner *fuse, *prev_fuse;
989 
990 	fuse = corner->fuse_corner;
991 	prev_fuse = fuse - 1;
992 
993 	f_high = fuse->max_freq;
994 	f_low = prev_fuse->max_freq;
995 	uV_high = fuse->uV;
996 	uV_low = prev_fuse->uV;
997 	f_diff = fuse->max_freq - corner->freq;
998 
999 	/*
1000 	 * Don't interpolate in the wrong direction. This could happen
1001 	 * if the adjusted fuse voltage overlaps with the previous fuse's
1002 	 * adjusted voltage.
1003 	 */
1004 	if (f_high <= f_low || uV_high <= uV_low || f_high <= corner->freq)
1005 		return corner->uV;
1006 
1007 	temp = f_diff * (uV_high - uV_low);
1008 	temp = div64_ul(temp, f_high - f_low);
1009 
1010 	/*
1011 	 * max_volt_scale has units of uV/MHz while freq values
1012 	 * have units of Hz.  Divide by 1000000 to convert to.
1013 	 */
1014 	temp_limit = f_diff * fdata->max_volt_scale;
1015 	do_div(temp_limit, 1000000);
1016 
1017 	uV = uV_high - min(temp, temp_limit);
1018 	return roundup(uV, step_volt);
1019 }
1020 
1021 static unsigned int cpr_get_fuse_corner(struct dev_pm_opp *opp)
1022 {
1023 	struct device_node *np;
1024 	unsigned int fuse_corner = 0;
1025 
1026 	np = dev_pm_opp_get_of_node(opp);
1027 	if (of_property_read_u32(np, "qcom,opp-fuse-level", &fuse_corner))
1028 		pr_err("%s: missing 'qcom,opp-fuse-level' property\n",
1029 		       __func__);
1030 
1031 	of_node_put(np);
1032 
1033 	return fuse_corner;
1034 }
1035 
1036 static unsigned long cpr_get_opp_hz_for_req(struct dev_pm_opp *ref,
1037 					    struct device *cpu_dev)
1038 {
1039 	struct device_node *ref_np __free(device_node) = NULL;
1040 	struct device_node *desc_np __free(device_node) =
1041 		dev_pm_opp_of_get_opp_desc_node(cpu_dev);
1042 
1043 	if (!desc_np)
1044 		return 0;
1045 
1046 	ref_np = dev_pm_opp_get_of_node(ref);
1047 	if (!ref_np)
1048 		return 0;
1049 
1050 	for_each_available_child_of_node_scoped(desc_np, child_np) {
1051 		struct device_node *child_req_np __free(device_node) =
1052 			of_parse_phandle(child_np, "required-opps", 0);
1053 
1054 		if (child_req_np == ref_np) {
1055 			u64 rate = 0;
1056 
1057 			of_property_read_u64(child_np, "opp-hz", &rate);
1058 			return (unsigned long) rate;
1059 		}
1060 	}
1061 
1062 	return 0;
1063 }
1064 
1065 static int cpr_corner_init(struct cpr_drv *drv)
1066 {
1067 	const struct cpr_desc *desc = drv->desc;
1068 	const struct cpr_fuse *fuses = drv->cpr_fuses;
1069 	int i, level, scaling = 0;
1070 	unsigned int fnum, fc;
1071 	const char *quot_offset;
1072 	struct fuse_corner *fuse, *prev_fuse;
1073 	struct corner *corner, *end;
1074 	struct corner_data *cdata;
1075 	const struct fuse_corner_data *fdata;
1076 	bool apply_scaling;
1077 	unsigned long freq_diff, freq_diff_mhz;
1078 	unsigned long freq;
1079 	int step_volt = regulator_get_linear_step(drv->vdd_apc);
1080 	struct dev_pm_opp *opp;
1081 
1082 	if (!step_volt)
1083 		return -EINVAL;
1084 
1085 	corner = drv->corners;
1086 	end = &corner[drv->num_corners - 1];
1087 
1088 	cdata = devm_kcalloc(drv->dev, drv->num_corners,
1089 			     sizeof(struct corner_data),
1090 			     GFP_KERNEL);
1091 	if (!cdata)
1092 		return -ENOMEM;
1093 
1094 	/*
1095 	 * Store maximum frequency for each fuse corner based on the frequency
1096 	 * plan
1097 	 */
1098 	for (level = 1; level <= drv->num_corners; level++) {
1099 		opp = dev_pm_opp_find_level_exact(&drv->pd.dev, level);
1100 		if (IS_ERR(opp))
1101 			return -EINVAL;
1102 		fc = cpr_get_fuse_corner(opp);
1103 		if (!fc) {
1104 			dev_pm_opp_put(opp);
1105 			return -EINVAL;
1106 		}
1107 		fnum = fc - 1;
1108 		freq = cpr_get_opp_hz_for_req(opp, drv->attached_cpu_dev);
1109 		if (!freq) {
1110 			dev_pm_opp_put(opp);
1111 			return -EINVAL;
1112 		}
1113 		cdata[level - 1].fuse_corner = fnum;
1114 		cdata[level - 1].freq = freq;
1115 
1116 		fuse = &drv->fuse_corners[fnum];
1117 		dev_dbg(drv->dev, "freq: %lu level: %u fuse level: %u\n",
1118 			freq, dev_pm_opp_get_level(opp) - 1, fnum);
1119 		if (freq > fuse->max_freq)
1120 			fuse->max_freq = freq;
1121 		dev_pm_opp_put(opp);
1122 	}
1123 
1124 	/*
1125 	 * Get the quotient adjustment scaling factor, according to:
1126 	 *
1127 	 * scaling = min(1000 * (QUOT(corner_N) - QUOT(corner_N-1))
1128 	 *		/ (freq(corner_N) - freq(corner_N-1)), max_factor)
1129 	 *
1130 	 * QUOT(corner_N):	quotient read from fuse for fuse corner N
1131 	 * QUOT(corner_N-1):	quotient read from fuse for fuse corner (N - 1)
1132 	 * freq(corner_N):	max frequency in MHz supported by fuse corner N
1133 	 * freq(corner_N-1):	max frequency in MHz supported by fuse corner
1134 	 *			 (N - 1)
1135 	 *
1136 	 * Then walk through the corners mapped to each fuse corner
1137 	 * and calculate the quotient adjustment for each one using the
1138 	 * following formula:
1139 	 *
1140 	 * quot_adjust = (freq_max - freq_corner) * scaling / 1000
1141 	 *
1142 	 * freq_max: max frequency in MHz supported by the fuse corner
1143 	 * freq_corner: frequency in MHz corresponding to the corner
1144 	 * scaling: calculated from above equation
1145 	 *
1146 	 *
1147 	 *     +                           +
1148 	 *     |                         v |
1149 	 *   q |           f c           o |           f c
1150 	 *   u |         c               l |         c
1151 	 *   o |       f                 t |       f
1152 	 *   t |     c                   a |     c
1153 	 *     | c f                     g | c f
1154 	 *     |                         e |
1155 	 *     +---------------            +----------------
1156 	 *       0 1 2 3 4 5 6               0 1 2 3 4 5 6
1157 	 *          corner                      corner
1158 	 *
1159 	 *    c = corner
1160 	 *    f = fuse corner
1161 	 *
1162 	 */
1163 	for (apply_scaling = false, i = 0; corner <= end; corner++, i++) {
1164 		fnum = cdata[i].fuse_corner;
1165 		fdata = &desc->cpr_fuses.fuse_corner_data[fnum];
1166 		quot_offset = fuses[fnum].quotient_offset;
1167 		fuse = &drv->fuse_corners[fnum];
1168 		if (fnum)
1169 			prev_fuse = &drv->fuse_corners[fnum - 1];
1170 		else
1171 			prev_fuse = NULL;
1172 
1173 		corner->fuse_corner = fuse;
1174 		corner->freq = cdata[i].freq;
1175 		corner->uV = fuse->uV;
1176 
1177 		if (prev_fuse && cdata[i - 1].freq == prev_fuse->max_freq) {
1178 			scaling = cpr_calculate_scaling(quot_offset, drv,
1179 							fdata, corner);
1180 			if (scaling < 0)
1181 				return scaling;
1182 
1183 			apply_scaling = true;
1184 		} else if (corner->freq == fuse->max_freq) {
1185 			/* This is a fuse corner; don't scale anything */
1186 			apply_scaling = false;
1187 		}
1188 
1189 		if (apply_scaling) {
1190 			freq_diff = fuse->max_freq - corner->freq;
1191 			freq_diff_mhz = freq_diff / 1000000;
1192 			corner->quot_adjust = scaling * freq_diff_mhz / 1000;
1193 
1194 			corner->uV = cpr_interpolate(corner, step_volt, fdata);
1195 		}
1196 
1197 		corner->max_uV = fuse->max_uV;
1198 		corner->min_uV = fuse->min_uV;
1199 		corner->uV = clamp(corner->uV, corner->min_uV, corner->max_uV);
1200 		corner->last_uV = corner->uV;
1201 
1202 		/* Reduce the ceiling voltage if needed */
1203 		if (desc->reduce_to_corner_uV && corner->uV < corner->max_uV)
1204 			corner->max_uV = corner->uV;
1205 		else if (desc->reduce_to_fuse_uV && fuse->uV < corner->max_uV)
1206 			corner->max_uV = max(corner->min_uV, fuse->uV);
1207 
1208 		dev_dbg(drv->dev, "corner %d: [%d %d %d] quot %d\n", i,
1209 			corner->min_uV, corner->uV, corner->max_uV,
1210 			fuse->quot - corner->quot_adjust);
1211 	}
1212 
1213 	return 0;
1214 }
1215 
1216 static const struct cpr_fuse *cpr_get_fuses(struct cpr_drv *drv)
1217 {
1218 	const struct cpr_desc *desc = drv->desc;
1219 	struct cpr_fuse *fuses;
1220 	int i;
1221 
1222 	fuses = devm_kcalloc(drv->dev, desc->num_fuse_corners,
1223 			     sizeof(struct cpr_fuse),
1224 			     GFP_KERNEL);
1225 	if (!fuses)
1226 		return ERR_PTR(-ENOMEM);
1227 
1228 	for (i = 0; i < desc->num_fuse_corners; i++) {
1229 		char tbuf[32];
1230 
1231 		snprintf(tbuf, 32, "cpr_ring_osc%d", i + 1);
1232 		fuses[i].ring_osc = devm_kstrdup(drv->dev, tbuf, GFP_KERNEL);
1233 		if (!fuses[i].ring_osc)
1234 			return ERR_PTR(-ENOMEM);
1235 
1236 		snprintf(tbuf, 32, "cpr_init_voltage%d", i + 1);
1237 		fuses[i].init_voltage = devm_kstrdup(drv->dev, tbuf,
1238 						     GFP_KERNEL);
1239 		if (!fuses[i].init_voltage)
1240 			return ERR_PTR(-ENOMEM);
1241 
1242 		snprintf(tbuf, 32, "cpr_quotient%d", i + 1);
1243 		fuses[i].quotient = devm_kstrdup(drv->dev, tbuf, GFP_KERNEL);
1244 		if (!fuses[i].quotient)
1245 			return ERR_PTR(-ENOMEM);
1246 
1247 		snprintf(tbuf, 32, "cpr_quotient_offset%d", i + 1);
1248 		fuses[i].quotient_offset = devm_kstrdup(drv->dev, tbuf,
1249 							GFP_KERNEL);
1250 		if (!fuses[i].quotient_offset)
1251 			return ERR_PTR(-ENOMEM);
1252 	}
1253 
1254 	return fuses;
1255 }
1256 
1257 static void cpr_set_loop_allowed(struct cpr_drv *drv)
1258 {
1259 	drv->loop_disabled = false;
1260 }
1261 
1262 static int cpr_init_parameters(struct cpr_drv *drv)
1263 {
1264 	const struct cpr_desc *desc = drv->desc;
1265 	struct clk *clk;
1266 
1267 	clk = clk_get(drv->dev, "ref");
1268 	if (IS_ERR(clk))
1269 		return PTR_ERR(clk);
1270 
1271 	drv->ref_clk_khz = clk_get_rate(clk) / 1000;
1272 	clk_put(clk);
1273 
1274 	if (desc->timer_cons_up > RBIF_TIMER_ADJ_CONS_UP_MASK ||
1275 	    desc->timer_cons_down > RBIF_TIMER_ADJ_CONS_DOWN_MASK ||
1276 	    desc->up_threshold > RBCPR_CTL_UP_THRESHOLD_MASK ||
1277 	    desc->down_threshold > RBCPR_CTL_DN_THRESHOLD_MASK ||
1278 	    desc->idle_clocks > RBCPR_STEP_QUOT_IDLE_CLK_MASK ||
1279 	    desc->clamp_timer_interval > RBIF_TIMER_ADJ_CLAMP_INT_MASK)
1280 		return -EINVAL;
1281 
1282 	dev_dbg(drv->dev, "up threshold = %u, down threshold = %u\n",
1283 		desc->up_threshold, desc->down_threshold);
1284 
1285 	return 0;
1286 }
1287 
1288 static int cpr_find_initial_corner(struct cpr_drv *drv)
1289 {
1290 	unsigned long rate;
1291 	const struct corner *end;
1292 	struct corner *iter;
1293 	unsigned int i = 0;
1294 
1295 	if (!drv->cpu_clk) {
1296 		dev_err(drv->dev, "cannot get rate from NULL clk\n");
1297 		return -EINVAL;
1298 	}
1299 
1300 	end = &drv->corners[drv->num_corners - 1];
1301 	rate = clk_get_rate(drv->cpu_clk);
1302 
1303 	/*
1304 	 * Some bootloaders set a CPU clock frequency that is not defined
1305 	 * in the OPP table. When running at an unlisted frequency,
1306 	 * cpufreq_online() will change to the OPP which has the lowest
1307 	 * frequency, at or above the unlisted frequency.
1308 	 * Since cpufreq_online() always "rounds up" in the case of an
1309 	 * unlisted frequency, this function always "rounds down" in case
1310 	 * of an unlisted frequency. That way, when cpufreq_online()
1311 	 * triggers the first ever call to cpr_set_performance_state(),
1312 	 * it will correctly determine the direction as UP.
1313 	 */
1314 	for (iter = drv->corners; iter <= end; iter++) {
1315 		if (iter->freq > rate)
1316 			break;
1317 		i++;
1318 		if (iter->freq == rate) {
1319 			drv->corner = iter;
1320 			break;
1321 		}
1322 		if (iter->freq < rate)
1323 			drv->corner = iter;
1324 	}
1325 
1326 	if (!drv->corner) {
1327 		dev_err(drv->dev, "boot up corner not found\n");
1328 		return -EINVAL;
1329 	}
1330 
1331 	dev_dbg(drv->dev, "boot up perf state: %u\n", i);
1332 
1333 	return 0;
1334 }
1335 
1336 static const struct cpr_desc qcs404_cpr_desc = {
1337 	.num_fuse_corners = 3,
1338 	.min_diff_quot = CPR_FUSE_MIN_QUOT_DIFF,
1339 	.step_quot = (int []){ 25, 25, 25, },
1340 	.timer_delay_us = 5000,
1341 	.timer_cons_up = 0,
1342 	.timer_cons_down = 2,
1343 	.up_threshold = 1,
1344 	.down_threshold = 3,
1345 	.idle_clocks = 15,
1346 	.gcnt_us = 1,
1347 	.vdd_apc_step_up_limit = 1,
1348 	.vdd_apc_step_down_limit = 1,
1349 	.cpr_fuses = {
1350 		.init_voltage_step = 8000,
1351 		.init_voltage_width = 6,
1352 		.fuse_corner_data = (struct fuse_corner_data[]){
1353 			/* fuse corner 0 */
1354 			{
1355 				.ref_uV = 1224000,
1356 				.max_uV = 1224000,
1357 				.min_uV = 1048000,
1358 				.max_volt_scale = 0,
1359 				.max_quot_scale = 0,
1360 				.quot_offset = 0,
1361 				.quot_scale = 1,
1362 				.quot_adjust = 0,
1363 				.quot_offset_scale = 5,
1364 				.quot_offset_adjust = 0,
1365 			},
1366 			/* fuse corner 1 */
1367 			{
1368 				.ref_uV = 1288000,
1369 				.max_uV = 1288000,
1370 				.min_uV = 1048000,
1371 				.max_volt_scale = 2000,
1372 				.max_quot_scale = 1400,
1373 				.quot_offset = 0,
1374 				.quot_scale = 1,
1375 				.quot_adjust = -20,
1376 				.quot_offset_scale = 5,
1377 				.quot_offset_adjust = 0,
1378 			},
1379 			/* fuse corner 2 */
1380 			{
1381 				.ref_uV = 1352000,
1382 				.max_uV = 1384000,
1383 				.min_uV = 1088000,
1384 				.max_volt_scale = 2000,
1385 				.max_quot_scale = 1400,
1386 				.quot_offset = 0,
1387 				.quot_scale = 1,
1388 				.quot_adjust = 0,
1389 				.quot_offset_scale = 5,
1390 				.quot_offset_adjust = 0,
1391 			},
1392 		},
1393 	},
1394 };
1395 
1396 static const struct acc_desc qcs404_acc_desc = {
1397 	.settings = (struct reg_sequence[]){
1398 		{ 0xb120, 0x1041040 },
1399 		{ 0xb124, 0x41 },
1400 		{ 0xb120, 0x0 },
1401 		{ 0xb124, 0x0 },
1402 		{ 0xb120, 0x0 },
1403 		{ 0xb124, 0x0 },
1404 	},
1405 	.config = (struct reg_sequence[]){
1406 		{ 0xb138, 0xff },
1407 		{ 0xb130, 0x5555 },
1408 	},
1409 	.num_regs_per_fuse = 2,
1410 };
1411 
1412 static const struct cpr_acc_desc qcs404_cpr_acc_desc = {
1413 	.cpr_desc = &qcs404_cpr_desc,
1414 	.acc_desc = &qcs404_acc_desc,
1415 };
1416 
1417 static int cpr_power_off(struct generic_pm_domain *domain)
1418 {
1419 	struct cpr_drv *drv = container_of(domain, struct cpr_drv, pd);
1420 
1421 	return cpr_disable(drv);
1422 }
1423 
1424 static int cpr_power_on(struct generic_pm_domain *domain)
1425 {
1426 	struct cpr_drv *drv = container_of(domain, struct cpr_drv, pd);
1427 
1428 	return cpr_enable(drv);
1429 }
1430 
1431 static int cpr_pd_attach_dev(struct generic_pm_domain *domain,
1432 			     struct device *dev)
1433 {
1434 	struct cpr_drv *drv = container_of(domain, struct cpr_drv, pd);
1435 	const struct acc_desc *acc_desc = drv->acc_desc;
1436 	int ret;
1437 
1438 	guard(mutex)(&drv->lock);
1439 
1440 	dev_dbg(drv->dev, "attach callback for: %s\n", dev_name(dev));
1441 
1442 	/*
1443 	 * This driver only supports scaling voltage for a CPU cluster
1444 	 * where all CPUs in the cluster share a single regulator.
1445 	 * Therefore, save the struct device pointer only for the first
1446 	 * CPU device that gets attached. There is no need to do any
1447 	 * additional initialization when further CPUs get attached.
1448 	 */
1449 	if (drv->attached_cpu_dev)
1450 		return 0;
1451 
1452 	/*
1453 	 * cpr_scale_voltage() requires the direction (if we are changing
1454 	 * to a higher or lower OPP). The first time
1455 	 * cpr_set_performance_state() is called, there is no previous
1456 	 * performance state defined. Therefore, we call
1457 	 * cpr_find_initial_corner() that gets the CPU clock frequency
1458 	 * set by the bootloader, so that we can determine the direction
1459 	 * the first time cpr_set_performance_state() is called.
1460 	 */
1461 	drv->cpu_clk = devm_clk_get(dev, NULL);
1462 	if (IS_ERR(drv->cpu_clk))
1463 		return dev_err_probe(drv->dev, PTR_ERR(drv->cpu_clk),
1464 				     "could not get cpu clk\n");
1465 
1466 	drv->attached_cpu_dev = dev;
1467 
1468 	dev_dbg(drv->dev, "using cpu clk from: %s\n",
1469 		dev_name(drv->attached_cpu_dev));
1470 
1471 	/*
1472 	 * Everything related to (virtual) corners has to be initialized
1473 	 * here, when attaching to the power domain, since we need to know
1474 	 * the maximum frequency for each fuse corner, and this is only
1475 	 * available after the cpufreq driver has attached to us.
1476 	 * The reason for this is that we need to know the highest
1477 	 * frequency associated with each fuse corner.
1478 	 */
1479 	ret = dev_pm_opp_get_opp_count(&drv->pd.dev);
1480 	if (ret < 0) {
1481 		dev_err(drv->dev, "could not get OPP count\n");
1482 		return ret;
1483 	}
1484 	drv->num_corners = ret;
1485 
1486 	if (drv->num_corners < 2) {
1487 		dev_err(drv->dev, "need at least 2 OPPs to use CPR\n");
1488 		return -EINVAL;
1489 	}
1490 
1491 	drv->corners = devm_kcalloc(drv->dev, drv->num_corners,
1492 				    sizeof(*drv->corners),
1493 				    GFP_KERNEL);
1494 	if (!drv->corners)
1495 		return -ENOMEM;
1496 
1497 	ret = cpr_corner_init(drv);
1498 	if (ret)
1499 		return ret;
1500 
1501 	cpr_set_loop_allowed(drv);
1502 
1503 	ret = cpr_init_parameters(drv);
1504 	if (ret)
1505 		return ret;
1506 
1507 	/* Configure CPR HW but keep it disabled */
1508 	ret = cpr_config(drv);
1509 	if (ret)
1510 		return ret;
1511 
1512 	ret = cpr_find_initial_corner(drv);
1513 	if (ret)
1514 		return ret;
1515 
1516 	if (acc_desc->config)
1517 		regmap_multi_reg_write(drv->tcsr, acc_desc->config,
1518 				       acc_desc->num_regs_per_fuse);
1519 
1520 	/* Enable ACC if required */
1521 	if (acc_desc->enable_mask)
1522 		regmap_update_bits(drv->tcsr, acc_desc->enable_reg,
1523 				   acc_desc->enable_mask,
1524 				   acc_desc->enable_mask);
1525 
1526 	dev_info(drv->dev, "driver initialized with %u OPPs\n",
1527 		 drv->num_corners);
1528 
1529 	return 0;
1530 }
1531 
1532 static int cpr_debug_info_show(struct seq_file *s, void *unused)
1533 {
1534 	u32 gcnt, ro_sel, ctl, irq_status, reg, error_steps;
1535 	u32 step_dn, step_up, error, error_lt0, busy;
1536 	struct cpr_drv *drv = s->private;
1537 	struct fuse_corner *fuse_corner;
1538 	struct corner *corner;
1539 
1540 	corner = drv->corner;
1541 	fuse_corner = corner->fuse_corner;
1542 
1543 	seq_printf(s, "corner, current_volt = %d uV\n",
1544 		       corner->last_uV);
1545 
1546 	ro_sel = fuse_corner->ring_osc_idx;
1547 	gcnt = cpr_read(drv, REG_RBCPR_GCNT_TARGET(ro_sel));
1548 	seq_printf(s, "rbcpr_gcnt_target (%u) = %#02X\n", ro_sel, gcnt);
1549 
1550 	ctl = cpr_read(drv, REG_RBCPR_CTL);
1551 	seq_printf(s, "rbcpr_ctl = %#02X\n", ctl);
1552 
1553 	irq_status = cpr_read(drv, REG_RBIF_IRQ_STATUS);
1554 	seq_printf(s, "rbcpr_irq_status = %#02X\n", irq_status);
1555 
1556 	reg = cpr_read(drv, REG_RBCPR_RESULT_0);
1557 	seq_printf(s, "rbcpr_result_0 = %#02X\n", reg);
1558 
1559 	step_dn = reg & 0x01;
1560 	step_up = (reg >> RBCPR_RESULT0_STEP_UP_SHIFT) & 0x01;
1561 	seq_printf(s, "  [step_dn = %u", step_dn);
1562 
1563 	seq_printf(s, ", step_up = %u", step_up);
1564 
1565 	error_steps = (reg >> RBCPR_RESULT0_ERROR_STEPS_SHIFT)
1566 				& RBCPR_RESULT0_ERROR_STEPS_MASK;
1567 	seq_printf(s, ", error_steps = %u", error_steps);
1568 
1569 	error = (reg >> RBCPR_RESULT0_ERROR_SHIFT) & RBCPR_RESULT0_ERROR_MASK;
1570 	seq_printf(s, ", error = %u", error);
1571 
1572 	error_lt0 = (reg >> RBCPR_RESULT0_ERROR_LT0_SHIFT) & 0x01;
1573 	seq_printf(s, ", error_lt_0 = %u", error_lt0);
1574 
1575 	busy = (reg >> RBCPR_RESULT0_BUSY_SHIFT) & 0x01;
1576 	seq_printf(s, ", busy = %u]\n", busy);
1577 
1578 	return 0;
1579 }
1580 DEFINE_SHOW_ATTRIBUTE(cpr_debug_info);
1581 
1582 static void cpr_debugfs_init(struct cpr_drv *drv)
1583 {
1584 	drv->debugfs = debugfs_create_dir("qcom_cpr", NULL);
1585 
1586 	debugfs_create_file("debug_info", 0444, drv->debugfs,
1587 			    drv, &cpr_debug_info_fops);
1588 }
1589 
1590 static int cpr_probe(struct platform_device *pdev)
1591 {
1592 	struct device *dev = &pdev->dev;
1593 	struct cpr_drv *drv;
1594 	int irq, ret;
1595 	const struct cpr_acc_desc *data;
1596 	struct device_node *np;
1597 	u32 cpr_rev = FUSE_REVISION_UNKNOWN;
1598 
1599 	data = of_device_get_match_data(dev);
1600 	if (!data || !data->cpr_desc || !data->acc_desc)
1601 		return -EINVAL;
1602 
1603 	drv = devm_kzalloc(dev, sizeof(*drv), GFP_KERNEL);
1604 	if (!drv)
1605 		return -ENOMEM;
1606 	drv->dev = dev;
1607 	drv->desc = data->cpr_desc;
1608 	drv->acc_desc = data->acc_desc;
1609 
1610 	drv->fuse_corners = devm_kcalloc(dev, drv->desc->num_fuse_corners,
1611 					 sizeof(*drv->fuse_corners),
1612 					 GFP_KERNEL);
1613 	if (!drv->fuse_corners)
1614 		return -ENOMEM;
1615 
1616 	np = of_parse_phandle(dev->of_node, "acc-syscon", 0);
1617 	if (!np)
1618 		return -ENODEV;
1619 
1620 	drv->tcsr = syscon_node_to_regmap(np);
1621 	of_node_put(np);
1622 	if (IS_ERR(drv->tcsr))
1623 		return PTR_ERR(drv->tcsr);
1624 
1625 	drv->base = devm_platform_ioremap_resource(pdev, 0);
1626 	if (IS_ERR(drv->base))
1627 		return PTR_ERR(drv->base);
1628 
1629 	irq = platform_get_irq(pdev, 0);
1630 	if (irq < 0)
1631 		return -EINVAL;
1632 
1633 	drv->vdd_apc = devm_regulator_get(dev, "vdd-apc");
1634 	if (IS_ERR(drv->vdd_apc))
1635 		return PTR_ERR(drv->vdd_apc);
1636 
1637 	/*
1638 	 * Initialize fuse corners, since it simply depends
1639 	 * on data in efuses.
1640 	 * Everything related to (virtual) corners has to be
1641 	 * initialized after attaching to the power domain,
1642 	 * since it depends on the CPU's OPP table.
1643 	 */
1644 	ret = nvmem_cell_read_variable_le_u32(dev, "cpr_fuse_revision", &cpr_rev);
1645 	if (ret)
1646 		return ret;
1647 
1648 	drv->cpr_fuses = cpr_get_fuses(drv);
1649 	if (IS_ERR(drv->cpr_fuses))
1650 		return PTR_ERR(drv->cpr_fuses);
1651 
1652 	ret = cpr_populate_ring_osc_idx(drv);
1653 	if (ret)
1654 		return ret;
1655 
1656 	ret = cpr_fuse_corner_init(drv);
1657 	if (ret)
1658 		return ret;
1659 
1660 	mutex_init(&drv->lock);
1661 
1662 	ret = devm_request_threaded_irq(dev, irq, NULL,
1663 					cpr_irq_handler,
1664 					IRQF_ONESHOT | IRQF_TRIGGER_RISING,
1665 					"cpr", drv);
1666 	if (ret)
1667 		return ret;
1668 
1669 	drv->pd.name = devm_kstrdup_const(dev, dev->of_node->full_name,
1670 					  GFP_KERNEL);
1671 	if (!drv->pd.name)
1672 		return -EINVAL;
1673 
1674 	drv->pd.power_off = cpr_power_off;
1675 	drv->pd.power_on = cpr_power_on;
1676 	drv->pd.set_performance_state = cpr_set_performance_state;
1677 	drv->pd.attach_dev = cpr_pd_attach_dev;
1678 
1679 	ret = pm_genpd_init(&drv->pd, NULL, true);
1680 	if (ret)
1681 		return ret;
1682 
1683 	ret = of_genpd_add_provider_simple(dev->of_node, &drv->pd);
1684 	if (ret)
1685 		goto err_remove_genpd;
1686 
1687 	platform_set_drvdata(pdev, drv);
1688 	cpr_debugfs_init(drv);
1689 
1690 	return 0;
1691 
1692 err_remove_genpd:
1693 	pm_genpd_remove(&drv->pd);
1694 	return ret;
1695 }
1696 
1697 static void cpr_remove(struct platform_device *pdev)
1698 {
1699 	struct cpr_drv *drv = platform_get_drvdata(pdev);
1700 
1701 	if (cpr_is_allowed(drv)) {
1702 		cpr_ctl_disable(drv);
1703 		cpr_irq_set(drv, 0);
1704 	}
1705 
1706 	of_genpd_del_provider(pdev->dev.of_node);
1707 	pm_genpd_remove(&drv->pd);
1708 
1709 	debugfs_remove_recursive(drv->debugfs);
1710 }
1711 
1712 static const struct of_device_id cpr_match_table[] = {
1713 	{ .compatible = "qcom,qcs404-cpr", .data = &qcs404_cpr_acc_desc },
1714 	{ }
1715 };
1716 MODULE_DEVICE_TABLE(of, cpr_match_table);
1717 
1718 static struct platform_driver cpr_driver = {
1719 	.probe		= cpr_probe,
1720 	.remove_new	= cpr_remove,
1721 	.driver		= {
1722 		.name	= "qcom-cpr",
1723 		.of_match_table = cpr_match_table,
1724 	},
1725 };
1726 module_platform_driver(cpr_driver);
1727 
1728 MODULE_DESCRIPTION("Core Power Reduction (CPR) driver");
1729 MODULE_LICENSE("GPL v2");
1730