xref: /linux/drivers/pmdomain/qcom/cpr.c (revision 66ab322c618cd4581917e2981ddece5db7fb52a3)
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 corner		*corners;
243 
244 	const struct cpr_desc *desc;
245 	const struct acc_desc *acc_desc;
246 	const struct cpr_fuse *cpr_fuses;
247 
248 	struct dentry *debugfs;
249 
250 	struct fuse_corner	fuse_corners[];
251 };
252 
253 static bool cpr_is_allowed(struct cpr_drv *drv)
254 {
255 	return !drv->loop_disabled;
256 }
257 
258 static void cpr_write(struct cpr_drv *drv, u32 offset, u32 value)
259 {
260 	writel_relaxed(value, drv->base + offset);
261 }
262 
263 static u32 cpr_read(struct cpr_drv *drv, u32 offset)
264 {
265 	return readl_relaxed(drv->base + offset);
266 }
267 
268 static void
269 cpr_masked_write(struct cpr_drv *drv, u32 offset, u32 mask, u32 value)
270 {
271 	u32 val;
272 
273 	val = readl_relaxed(drv->base + offset);
274 	val &= ~mask;
275 	val |= value & mask;
276 	writel_relaxed(val, drv->base + offset);
277 }
278 
279 static void cpr_irq_clr(struct cpr_drv *drv)
280 {
281 	cpr_write(drv, REG_RBIF_IRQ_CLEAR, CPR_INT_ALL);
282 }
283 
284 static void cpr_irq_clr_nack(struct cpr_drv *drv)
285 {
286 	cpr_irq_clr(drv);
287 	cpr_write(drv, REG_RBIF_CONT_NACK_CMD, 1);
288 }
289 
290 static void cpr_irq_clr_ack(struct cpr_drv *drv)
291 {
292 	cpr_irq_clr(drv);
293 	cpr_write(drv, REG_RBIF_CONT_ACK_CMD, 1);
294 }
295 
296 static void cpr_irq_set(struct cpr_drv *drv, u32 int_bits)
297 {
298 	cpr_write(drv, REG_RBIF_IRQ_EN(0), int_bits);
299 }
300 
301 static void cpr_ctl_modify(struct cpr_drv *drv, u32 mask, u32 value)
302 {
303 	cpr_masked_write(drv, REG_RBCPR_CTL, mask, value);
304 }
305 
306 static void cpr_ctl_enable(struct cpr_drv *drv, struct corner *corner)
307 {
308 	u32 val, mask;
309 	const struct cpr_desc *desc = drv->desc;
310 
311 	/* Program Consecutive Up & Down */
312 	val = desc->timer_cons_down << RBIF_TIMER_ADJ_CONS_DOWN_SHIFT;
313 	val |= desc->timer_cons_up << RBIF_TIMER_ADJ_CONS_UP_SHIFT;
314 	mask = RBIF_TIMER_ADJ_CONS_UP_MASK | RBIF_TIMER_ADJ_CONS_DOWN_MASK;
315 	cpr_masked_write(drv, REG_RBIF_TIMER_ADJUST, mask, val);
316 	cpr_masked_write(drv, REG_RBCPR_CTL,
317 			 RBCPR_CTL_SW_AUTO_CONT_NACK_DN_EN |
318 			 RBCPR_CTL_SW_AUTO_CONT_ACK_EN,
319 			 corner->save_ctl);
320 	cpr_irq_set(drv, corner->save_irq);
321 
322 	if (cpr_is_allowed(drv) && corner->max_uV > corner->min_uV)
323 		val = RBCPR_CTL_LOOP_EN;
324 	else
325 		val = 0;
326 	cpr_ctl_modify(drv, RBCPR_CTL_LOOP_EN, val);
327 }
328 
329 static void cpr_ctl_disable(struct cpr_drv *drv)
330 {
331 	cpr_irq_set(drv, 0);
332 	cpr_ctl_modify(drv, RBCPR_CTL_SW_AUTO_CONT_NACK_DN_EN |
333 		       RBCPR_CTL_SW_AUTO_CONT_ACK_EN, 0);
334 	cpr_masked_write(drv, REG_RBIF_TIMER_ADJUST,
335 			 RBIF_TIMER_ADJ_CONS_UP_MASK |
336 			 RBIF_TIMER_ADJ_CONS_DOWN_MASK, 0);
337 	cpr_irq_clr(drv);
338 	cpr_write(drv, REG_RBIF_CONT_ACK_CMD, 1);
339 	cpr_write(drv, REG_RBIF_CONT_NACK_CMD, 1);
340 	cpr_ctl_modify(drv, RBCPR_CTL_LOOP_EN, 0);
341 }
342 
343 static bool cpr_ctl_is_enabled(struct cpr_drv *drv)
344 {
345 	u32 reg_val;
346 
347 	reg_val = cpr_read(drv, REG_RBCPR_CTL);
348 	return reg_val & RBCPR_CTL_LOOP_EN;
349 }
350 
351 static bool cpr_ctl_is_busy(struct cpr_drv *drv)
352 {
353 	u32 reg_val;
354 
355 	reg_val = cpr_read(drv, REG_RBCPR_RESULT_0);
356 	return reg_val & RBCPR_RESULT0_BUSY_MASK;
357 }
358 
359 static void cpr_corner_save(struct cpr_drv *drv, struct corner *corner)
360 {
361 	corner->save_ctl = cpr_read(drv, REG_RBCPR_CTL);
362 	corner->save_irq = cpr_read(drv, REG_RBIF_IRQ_EN(0));
363 }
364 
365 static void cpr_corner_restore(struct cpr_drv *drv, struct corner *corner)
366 {
367 	u32 gcnt, ctl, irq, ro_sel, step_quot;
368 	struct fuse_corner *fuse = corner->fuse_corner;
369 	const struct cpr_desc *desc = drv->desc;
370 	int i;
371 
372 	ro_sel = fuse->ring_osc_idx;
373 	gcnt = drv->gcnt;
374 	gcnt |= fuse->quot - corner->quot_adjust;
375 
376 	/* Program the step quotient and idle clocks */
377 	step_quot = desc->idle_clocks << RBCPR_STEP_QUOT_IDLE_CLK_SHIFT;
378 	step_quot |= fuse->step_quot & RBCPR_STEP_QUOT_STEPQUOT_MASK;
379 	cpr_write(drv, REG_RBCPR_STEP_QUOT, step_quot);
380 
381 	/* Clear the target quotient value and gate count of all ROs */
382 	for (i = 0; i < CPR_NUM_RING_OSC; i++)
383 		cpr_write(drv, REG_RBCPR_GCNT_TARGET(i), 0);
384 
385 	cpr_write(drv, REG_RBCPR_GCNT_TARGET(ro_sel), gcnt);
386 	ctl = corner->save_ctl;
387 	cpr_write(drv, REG_RBCPR_CTL, ctl);
388 	irq = corner->save_irq;
389 	cpr_irq_set(drv, irq);
390 	dev_dbg(drv->dev, "gcnt = %#08x, ctl = %#08x, irq = %#08x\n", gcnt,
391 		ctl, irq);
392 }
393 
394 static void cpr_set_acc(struct regmap *tcsr, struct fuse_corner *f,
395 			struct fuse_corner *end)
396 {
397 	if (f == end)
398 		return;
399 
400 	if (f < end) {
401 		for (f += 1; f <= end; f++)
402 			regmap_multi_reg_write(tcsr, f->accs, f->num_accs);
403 	} else {
404 		for (f -= 1; f >= end; f--)
405 			regmap_multi_reg_write(tcsr, f->accs, f->num_accs);
406 	}
407 }
408 
409 static int cpr_pre_voltage(struct cpr_drv *drv,
410 			   struct fuse_corner *fuse_corner,
411 			   enum voltage_change_dir dir)
412 {
413 	struct fuse_corner *prev_fuse_corner = drv->corner->fuse_corner;
414 
415 	if (drv->tcsr && dir == DOWN)
416 		cpr_set_acc(drv->tcsr, prev_fuse_corner, fuse_corner);
417 
418 	return 0;
419 }
420 
421 static int cpr_post_voltage(struct cpr_drv *drv,
422 			    struct fuse_corner *fuse_corner,
423 			    enum voltage_change_dir dir)
424 {
425 	struct fuse_corner *prev_fuse_corner = drv->corner->fuse_corner;
426 
427 	if (drv->tcsr && dir == UP)
428 		cpr_set_acc(drv->tcsr, prev_fuse_corner, fuse_corner);
429 
430 	return 0;
431 }
432 
433 static int cpr_scale_voltage(struct cpr_drv *drv, struct corner *corner,
434 			     int new_uV, enum voltage_change_dir dir)
435 {
436 	int ret;
437 	struct fuse_corner *fuse_corner = corner->fuse_corner;
438 
439 	ret = cpr_pre_voltage(drv, fuse_corner, dir);
440 	if (ret)
441 		return ret;
442 
443 	ret = regulator_set_voltage(drv->vdd_apc, new_uV, new_uV);
444 	if (ret) {
445 		dev_err_ratelimited(drv->dev, "failed to set apc voltage %d\n",
446 				    new_uV);
447 		return ret;
448 	}
449 
450 	ret = cpr_post_voltage(drv, fuse_corner, dir);
451 	if (ret)
452 		return ret;
453 
454 	return 0;
455 }
456 
457 static unsigned int cpr_get_cur_perf_state(struct cpr_drv *drv)
458 {
459 	return drv->corner ? drv->corner - drv->corners + 1 : 0;
460 }
461 
462 static int cpr_scale(struct cpr_drv *drv, enum voltage_change_dir dir)
463 {
464 	u32 val, error_steps, reg_mask;
465 	int last_uV, new_uV, step_uV, ret;
466 	struct corner *corner;
467 	const struct cpr_desc *desc = drv->desc;
468 
469 	if (dir != UP && dir != DOWN)
470 		return 0;
471 
472 	step_uV = regulator_get_linear_step(drv->vdd_apc);
473 	if (!step_uV)
474 		return -EINVAL;
475 
476 	corner = drv->corner;
477 
478 	val = cpr_read(drv, REG_RBCPR_RESULT_0);
479 
480 	error_steps = val >> RBCPR_RESULT0_ERROR_STEPS_SHIFT;
481 	error_steps &= RBCPR_RESULT0_ERROR_STEPS_MASK;
482 	last_uV = corner->last_uV;
483 
484 	if (dir == UP) {
485 		if (desc->clamp_timer_interval &&
486 		    error_steps < desc->up_threshold) {
487 			/*
488 			 * Handle the case where another measurement started
489 			 * after the interrupt was triggered due to a core
490 			 * exiting from power collapse.
491 			 */
492 			error_steps = max(desc->up_threshold,
493 					  desc->vdd_apc_step_up_limit);
494 		}
495 
496 		if (last_uV >= corner->max_uV) {
497 			cpr_irq_clr_nack(drv);
498 
499 			/* Maximize the UP threshold */
500 			reg_mask = RBCPR_CTL_UP_THRESHOLD_MASK;
501 			reg_mask <<= RBCPR_CTL_UP_THRESHOLD_SHIFT;
502 			val = reg_mask;
503 			cpr_ctl_modify(drv, reg_mask, val);
504 
505 			/* Disable UP interrupt */
506 			cpr_irq_set(drv, CPR_INT_DEFAULT & ~CPR_INT_UP);
507 
508 			return 0;
509 		}
510 
511 		if (error_steps > desc->vdd_apc_step_up_limit)
512 			error_steps = desc->vdd_apc_step_up_limit;
513 
514 		/* Calculate new voltage */
515 		new_uV = last_uV + error_steps * step_uV;
516 		new_uV = min(new_uV, corner->max_uV);
517 
518 		dev_dbg(drv->dev,
519 			"UP: -> new_uV: %d last_uV: %d perf state: %u\n",
520 			new_uV, last_uV, cpr_get_cur_perf_state(drv));
521 	} else {
522 		if (desc->clamp_timer_interval &&
523 		    error_steps < desc->down_threshold) {
524 			/*
525 			 * Handle the case where another measurement started
526 			 * after the interrupt was triggered due to a core
527 			 * exiting from power collapse.
528 			 */
529 			error_steps = max(desc->down_threshold,
530 					  desc->vdd_apc_step_down_limit);
531 		}
532 
533 		if (last_uV <= corner->min_uV) {
534 			cpr_irq_clr_nack(drv);
535 
536 			/* Enable auto nack down */
537 			reg_mask = RBCPR_CTL_SW_AUTO_CONT_NACK_DN_EN;
538 			val = RBCPR_CTL_SW_AUTO_CONT_NACK_DN_EN;
539 
540 			cpr_ctl_modify(drv, reg_mask, val);
541 
542 			/* Disable DOWN interrupt */
543 			cpr_irq_set(drv, CPR_INT_DEFAULT & ~CPR_INT_DOWN);
544 
545 			return 0;
546 		}
547 
548 		if (error_steps > desc->vdd_apc_step_down_limit)
549 			error_steps = desc->vdd_apc_step_down_limit;
550 
551 		/* Calculate new voltage */
552 		new_uV = last_uV - error_steps * step_uV;
553 		new_uV = max(new_uV, corner->min_uV);
554 
555 		dev_dbg(drv->dev,
556 			"DOWN: -> new_uV: %d last_uV: %d perf state: %u\n",
557 			new_uV, last_uV, cpr_get_cur_perf_state(drv));
558 	}
559 
560 	ret = cpr_scale_voltage(drv, corner, new_uV, dir);
561 	if (ret) {
562 		cpr_irq_clr_nack(drv);
563 		return ret;
564 	}
565 	drv->corner->last_uV = new_uV;
566 
567 	if (dir == UP) {
568 		/* Disable auto nack down */
569 		reg_mask = RBCPR_CTL_SW_AUTO_CONT_NACK_DN_EN;
570 		val = 0;
571 	} else {
572 		/* Restore default threshold for UP */
573 		reg_mask = RBCPR_CTL_UP_THRESHOLD_MASK;
574 		reg_mask <<= RBCPR_CTL_UP_THRESHOLD_SHIFT;
575 		val = desc->up_threshold;
576 		val <<= RBCPR_CTL_UP_THRESHOLD_SHIFT;
577 	}
578 
579 	cpr_ctl_modify(drv, reg_mask, val);
580 
581 	/* Re-enable default interrupts */
582 	cpr_irq_set(drv, CPR_INT_DEFAULT);
583 
584 	/* Ack */
585 	cpr_irq_clr_ack(drv);
586 
587 	return 0;
588 }
589 
590 static irqreturn_t cpr_irq_handler(int irq, void *dev)
591 {
592 	struct cpr_drv *drv = dev;
593 	const struct cpr_desc *desc = drv->desc;
594 	irqreturn_t ret = IRQ_HANDLED;
595 	u32 val;
596 
597 	mutex_lock(&drv->lock);
598 
599 	val = cpr_read(drv, REG_RBIF_IRQ_STATUS);
600 	if (drv->flags & FLAGS_IGNORE_1ST_IRQ_STATUS)
601 		val = cpr_read(drv, REG_RBIF_IRQ_STATUS);
602 
603 	dev_dbg(drv->dev, "IRQ_STATUS = %#02x\n", val);
604 
605 	if (!cpr_ctl_is_enabled(drv)) {
606 		dev_dbg(drv->dev, "CPR is disabled\n");
607 		ret = IRQ_NONE;
608 	} else if (cpr_ctl_is_busy(drv) && !desc->clamp_timer_interval) {
609 		dev_dbg(drv->dev, "CPR measurement is not ready\n");
610 	} else if (!cpr_is_allowed(drv)) {
611 		val = cpr_read(drv, REG_RBCPR_CTL);
612 		dev_err_ratelimited(drv->dev,
613 				    "Interrupt broken? RBCPR_CTL = %#02x\n",
614 				    val);
615 		ret = IRQ_NONE;
616 	} else {
617 		/*
618 		 * Following sequence of handling is as per each IRQ's
619 		 * priority
620 		 */
621 		if (val & CPR_INT_UP) {
622 			cpr_scale(drv, UP);
623 		} else if (val & CPR_INT_DOWN) {
624 			cpr_scale(drv, DOWN);
625 		} else if (val & CPR_INT_MIN) {
626 			cpr_irq_clr_nack(drv);
627 		} else if (val & CPR_INT_MAX) {
628 			cpr_irq_clr_nack(drv);
629 		} else if (val & CPR_INT_MID) {
630 			/* RBCPR_CTL_SW_AUTO_CONT_ACK_EN is enabled */
631 			dev_dbg(drv->dev, "IRQ occurred for Mid Flag\n");
632 		} else {
633 			dev_dbg(drv->dev,
634 				"IRQ occurred for unknown flag (%#08x)\n", val);
635 		}
636 
637 		/* Save register values for the corner */
638 		cpr_corner_save(drv, drv->corner);
639 	}
640 
641 	mutex_unlock(&drv->lock);
642 
643 	return ret;
644 }
645 
646 static int cpr_enable(struct cpr_drv *drv)
647 {
648 	int ret;
649 
650 	ret = regulator_enable(drv->vdd_apc);
651 	if (ret)
652 		return ret;
653 
654 	mutex_lock(&drv->lock);
655 
656 	if (cpr_is_allowed(drv) && drv->corner) {
657 		cpr_irq_clr(drv);
658 		cpr_corner_restore(drv, drv->corner);
659 		cpr_ctl_enable(drv, drv->corner);
660 	}
661 
662 	mutex_unlock(&drv->lock);
663 
664 	return 0;
665 }
666 
667 static int cpr_disable(struct cpr_drv *drv)
668 {
669 	mutex_lock(&drv->lock);
670 
671 	if (cpr_is_allowed(drv)) {
672 		cpr_ctl_disable(drv);
673 		cpr_irq_clr(drv);
674 	}
675 
676 	mutex_unlock(&drv->lock);
677 
678 	return regulator_disable(drv->vdd_apc);
679 }
680 
681 static int cpr_config(struct cpr_drv *drv)
682 {
683 	int i;
684 	u32 val, gcnt;
685 	struct corner *corner;
686 	const struct cpr_desc *desc = drv->desc;
687 
688 	/* Disable interrupt and CPR */
689 	cpr_write(drv, REG_RBIF_IRQ_EN(0), 0);
690 	cpr_write(drv, REG_RBCPR_CTL, 0);
691 
692 	/* Program the default HW ceiling, floor and vlevel */
693 	val = (RBIF_LIMIT_CEILING_DEFAULT & RBIF_LIMIT_CEILING_MASK)
694 		<< RBIF_LIMIT_CEILING_SHIFT;
695 	val |= RBIF_LIMIT_FLOOR_DEFAULT & RBIF_LIMIT_FLOOR_MASK;
696 	cpr_write(drv, REG_RBIF_LIMIT, val);
697 	cpr_write(drv, REG_RBIF_SW_VLEVEL, RBIF_SW_VLEVEL_DEFAULT);
698 
699 	/*
700 	 * Clear the target quotient value and gate count of all
701 	 * ring oscillators
702 	 */
703 	for (i = 0; i < CPR_NUM_RING_OSC; i++)
704 		cpr_write(drv, REG_RBCPR_GCNT_TARGET(i), 0);
705 
706 	/* Init and save gcnt */
707 	gcnt = (drv->ref_clk_khz * desc->gcnt_us) / 1000;
708 	gcnt = gcnt & RBCPR_GCNT_TARGET_GCNT_MASK;
709 	gcnt <<= RBCPR_GCNT_TARGET_GCNT_SHIFT;
710 	drv->gcnt = gcnt;
711 
712 	/* Program the delay count for the timer */
713 	val = (drv->ref_clk_khz * desc->timer_delay_us) / 1000;
714 	cpr_write(drv, REG_RBCPR_TIMER_INTERVAL, val);
715 	dev_dbg(drv->dev, "Timer count: %#0x (for %d us)\n", val,
716 		desc->timer_delay_us);
717 
718 	/* Program Consecutive Up & Down */
719 	val = desc->timer_cons_down << RBIF_TIMER_ADJ_CONS_DOWN_SHIFT;
720 	val |= desc->timer_cons_up << RBIF_TIMER_ADJ_CONS_UP_SHIFT;
721 	val |= desc->clamp_timer_interval << RBIF_TIMER_ADJ_CLAMP_INT_SHIFT;
722 	cpr_write(drv, REG_RBIF_TIMER_ADJUST, val);
723 
724 	/* Program the control register */
725 	val = desc->up_threshold << RBCPR_CTL_UP_THRESHOLD_SHIFT;
726 	val |= desc->down_threshold << RBCPR_CTL_DN_THRESHOLD_SHIFT;
727 	val |= RBCPR_CTL_TIMER_EN | RBCPR_CTL_COUNT_MODE;
728 	val |= RBCPR_CTL_SW_AUTO_CONT_ACK_EN;
729 	cpr_write(drv, REG_RBCPR_CTL, val);
730 
731 	for (i = 0; i < drv->num_corners; i++) {
732 		corner = &drv->corners[i];
733 		corner->save_ctl = val;
734 		corner->save_irq = CPR_INT_DEFAULT;
735 	}
736 
737 	cpr_irq_set(drv, CPR_INT_DEFAULT);
738 
739 	val = cpr_read(drv, REG_RBCPR_VERSION);
740 	if (val <= RBCPR_VER_2)
741 		drv->flags |= FLAGS_IGNORE_1ST_IRQ_STATUS;
742 
743 	return 0;
744 }
745 
746 static int cpr_set_performance_state(struct generic_pm_domain *domain,
747 				     unsigned int state)
748 {
749 	struct cpr_drv *drv = container_of(domain, struct cpr_drv, pd);
750 	struct corner *corner, *end;
751 	enum voltage_change_dir dir;
752 	int ret, new_uV;
753 
754 	guard(mutex)(&drv->lock);
755 
756 	dev_dbg(drv->dev, "%s: setting perf state: %u (prev state: %u)\n",
757 		__func__, state, cpr_get_cur_perf_state(drv));
758 
759 	/*
760 	 * Determine new corner we're going to.
761 	 * Remove one since lowest performance state is 1.
762 	 */
763 	corner = drv->corners + state - 1;
764 	end = &drv->corners[drv->num_corners - 1];
765 	if (corner > end || corner < drv->corners)
766 		return -EINVAL;
767 
768 	/* Determine direction */
769 	if (drv->corner > corner)
770 		dir = DOWN;
771 	else if (drv->corner < corner)
772 		dir = UP;
773 	else
774 		dir = NO_CHANGE;
775 
776 	if (cpr_is_allowed(drv))
777 		new_uV = corner->last_uV;
778 	else
779 		new_uV = corner->uV;
780 
781 	if (cpr_is_allowed(drv))
782 		cpr_ctl_disable(drv);
783 
784 	ret = cpr_scale_voltage(drv, corner, new_uV, dir);
785 	if (ret)
786 		return ret;
787 
788 	if (cpr_is_allowed(drv)) {
789 		cpr_irq_clr(drv);
790 		if (drv->corner != corner)
791 			cpr_corner_restore(drv, corner);
792 		cpr_ctl_enable(drv, corner);
793 	}
794 
795 	drv->corner = corner;
796 
797 	return 0;
798 }
799 
800 static int
801 cpr_populate_ring_osc_idx(struct cpr_drv *drv)
802 {
803 	struct fuse_corner *fuse = drv->fuse_corners;
804 	struct fuse_corner *end = fuse + drv->desc->num_fuse_corners;
805 	const struct cpr_fuse *fuses = drv->cpr_fuses;
806 	u32 data;
807 	int ret;
808 
809 	for (; fuse < end; fuse++, fuses++) {
810 		ret = nvmem_cell_read_variable_le_u32(drv->dev, fuses->ring_osc, &data);
811 		if (ret)
812 			return ret;
813 		fuse->ring_osc_idx = data;
814 	}
815 
816 	return 0;
817 }
818 
819 static int cpr_read_fuse_uV(const struct cpr_desc *desc,
820 			    const struct fuse_corner_data *fdata,
821 			    const char *init_v_efuse,
822 			    int step_volt,
823 			    struct cpr_drv *drv)
824 {
825 	int step_size_uV, steps, uV;
826 	u32 bits = 0;
827 	int ret;
828 
829 	ret = nvmem_cell_read_variable_le_u32(drv->dev, init_v_efuse, &bits);
830 	if (ret)
831 		return ret;
832 
833 	steps = bits & ~BIT(desc->cpr_fuses.init_voltage_width - 1);
834 	/* Not two's complement.. instead highest bit is sign bit */
835 	if (bits & BIT(desc->cpr_fuses.init_voltage_width - 1))
836 		steps = -steps;
837 
838 	step_size_uV = desc->cpr_fuses.init_voltage_step;
839 
840 	uV = fdata->ref_uV + steps * step_size_uV;
841 	return DIV_ROUND_UP(uV, step_volt) * step_volt;
842 }
843 
844 static int cpr_fuse_corner_init(struct cpr_drv *drv)
845 {
846 	const struct cpr_desc *desc = drv->desc;
847 	const struct cpr_fuse *fuses = drv->cpr_fuses;
848 	const struct acc_desc *acc_desc = drv->acc_desc;
849 	int i;
850 	unsigned int step_volt;
851 	struct fuse_corner_data *fdata;
852 	struct fuse_corner *fuse, *end;
853 	int uV;
854 	const struct reg_sequence *accs;
855 	int ret;
856 
857 	accs = acc_desc->settings;
858 
859 	step_volt = regulator_get_linear_step(drv->vdd_apc);
860 	if (!step_volt)
861 		return -EINVAL;
862 
863 	/* Populate fuse_corner members */
864 	fuse = drv->fuse_corners;
865 	end = &fuse[desc->num_fuse_corners - 1];
866 	fdata = desc->cpr_fuses.fuse_corner_data;
867 
868 	for (i = 0; fuse <= end; fuse++, fuses++, i++, fdata++) {
869 		/*
870 		 * Update SoC voltages: platforms might choose a different
871 		 * regulators than the one used to characterize the algorithms
872 		 * (ie, init_voltage_step).
873 		 */
874 		fdata->min_uV = roundup(fdata->min_uV, step_volt);
875 		fdata->max_uV = roundup(fdata->max_uV, step_volt);
876 
877 		/* Populate uV */
878 		uV = cpr_read_fuse_uV(desc, fdata, fuses->init_voltage,
879 				      step_volt, drv);
880 		if (uV < 0)
881 			return uV;
882 
883 		fuse->min_uV = fdata->min_uV;
884 		fuse->max_uV = fdata->max_uV;
885 		fuse->uV = clamp(uV, fuse->min_uV, fuse->max_uV);
886 
887 		if (fuse == end) {
888 			/*
889 			 * Allow the highest fuse corner's PVS voltage to
890 			 * define the ceiling voltage for that corner in order
891 			 * to support SoC's in which variable ceiling values
892 			 * are required.
893 			 */
894 			end->max_uV = max(end->max_uV, end->uV);
895 		}
896 
897 		/* Populate target quotient by scaling */
898 		ret = nvmem_cell_read_variable_le_u32(drv->dev, fuses->quotient, &fuse->quot);
899 		if (ret)
900 			return ret;
901 
902 		fuse->quot *= fdata->quot_scale;
903 		fuse->quot += fdata->quot_offset;
904 		fuse->quot += fdata->quot_adjust;
905 		fuse->step_quot = desc->step_quot[fuse->ring_osc_idx];
906 
907 		/* Populate acc settings */
908 		fuse->accs = accs;
909 		fuse->num_accs = acc_desc->num_regs_per_fuse;
910 		accs += acc_desc->num_regs_per_fuse;
911 	}
912 
913 	/*
914 	 * Restrict all fuse corner PVS voltages based upon per corner
915 	 * ceiling and floor voltages.
916 	 */
917 	for (fuse = drv->fuse_corners, i = 0; fuse <= end; fuse++, i++) {
918 		if (fuse->uV > fuse->max_uV)
919 			fuse->uV = fuse->max_uV;
920 		else if (fuse->uV < fuse->min_uV)
921 			fuse->uV = fuse->min_uV;
922 
923 		ret = regulator_is_supported_voltage(drv->vdd_apc,
924 						     fuse->min_uV,
925 						     fuse->min_uV);
926 		if (!ret) {
927 			dev_err(drv->dev,
928 				"min uV: %d (fuse corner: %d) not supported by regulator\n",
929 				fuse->min_uV, i);
930 			return -EINVAL;
931 		}
932 
933 		ret = regulator_is_supported_voltage(drv->vdd_apc,
934 						     fuse->max_uV,
935 						     fuse->max_uV);
936 		if (!ret) {
937 			dev_err(drv->dev,
938 				"max uV: %d (fuse corner: %d) not supported by regulator\n",
939 				fuse->max_uV, i);
940 			return -EINVAL;
941 		}
942 
943 		dev_dbg(drv->dev,
944 			"fuse corner %d: [%d %d %d] RO%hhu quot %d squot %d\n",
945 			i, fuse->min_uV, fuse->uV, fuse->max_uV,
946 			fuse->ring_osc_idx, fuse->quot, fuse->step_quot);
947 	}
948 
949 	return 0;
950 }
951 
952 static int cpr_calculate_scaling(const char *quot_offset,
953 				 struct cpr_drv *drv,
954 				 const struct fuse_corner_data *fdata,
955 				 const struct corner *corner)
956 {
957 	u32 quot_diff = 0;
958 	unsigned long freq_diff;
959 	int scaling;
960 	const struct fuse_corner *fuse, *prev_fuse;
961 	int ret;
962 
963 	fuse = corner->fuse_corner;
964 	prev_fuse = fuse - 1;
965 
966 	if (quot_offset) {
967 		ret = nvmem_cell_read_variable_le_u32(drv->dev, quot_offset, &quot_diff);
968 		if (ret)
969 			return ret;
970 
971 		quot_diff *= fdata->quot_offset_scale;
972 		quot_diff += fdata->quot_offset_adjust;
973 	} else {
974 		quot_diff = fuse->quot - prev_fuse->quot;
975 	}
976 
977 	freq_diff = fuse->max_freq - prev_fuse->max_freq;
978 	freq_diff /= 1000000; /* Convert to MHz */
979 	scaling = 1000 * quot_diff / freq_diff;
980 	return min(scaling, fdata->max_quot_scale);
981 }
982 
983 static int cpr_interpolate(const struct corner *corner, int step_volt,
984 			   const struct fuse_corner_data *fdata)
985 {
986 	unsigned long f_high, f_low, f_diff;
987 	int uV_high, uV_low, uV;
988 	u64 temp, temp_limit;
989 	const struct fuse_corner *fuse, *prev_fuse;
990 
991 	fuse = corner->fuse_corner;
992 	prev_fuse = fuse - 1;
993 
994 	f_high = fuse->max_freq;
995 	f_low = prev_fuse->max_freq;
996 	uV_high = fuse->uV;
997 	uV_low = prev_fuse->uV;
998 	f_diff = fuse->max_freq - corner->freq;
999 
1000 	/*
1001 	 * Don't interpolate in the wrong direction. This could happen
1002 	 * if the adjusted fuse voltage overlaps with the previous fuse's
1003 	 * adjusted voltage.
1004 	 */
1005 	if (f_high <= f_low || uV_high <= uV_low || f_high <= corner->freq)
1006 		return corner->uV;
1007 
1008 	temp = f_diff * (uV_high - uV_low);
1009 	temp = div64_ul(temp, f_high - f_low);
1010 
1011 	/*
1012 	 * max_volt_scale has units of uV/MHz while freq values
1013 	 * have units of Hz.  Divide by 1000000 to convert to.
1014 	 */
1015 	temp_limit = f_diff * fdata->max_volt_scale;
1016 	do_div(temp_limit, 1000000);
1017 
1018 	uV = uV_high - min(temp, temp_limit);
1019 	return roundup(uV, step_volt);
1020 }
1021 
1022 static unsigned int cpr_get_fuse_corner(struct dev_pm_opp *opp)
1023 {
1024 	struct device_node *np;
1025 	unsigned int fuse_corner = 0;
1026 
1027 	np = dev_pm_opp_get_of_node(opp);
1028 	if (of_property_read_u32(np, "qcom,opp-fuse-level", &fuse_corner))
1029 		pr_err("%s: missing 'qcom,opp-fuse-level' property\n",
1030 		       __func__);
1031 
1032 	of_node_put(np);
1033 
1034 	return fuse_corner;
1035 }
1036 
1037 static unsigned long cpr_get_opp_hz_for_req(struct dev_pm_opp *ref,
1038 					    struct device *cpu_dev)
1039 {
1040 	struct device_node *ref_np __free(device_node) = NULL;
1041 	struct device_node *desc_np __free(device_node) =
1042 		dev_pm_opp_of_get_opp_desc_node(cpu_dev);
1043 
1044 	if (!desc_np)
1045 		return 0;
1046 
1047 	ref_np = dev_pm_opp_get_of_node(ref);
1048 	if (!ref_np)
1049 		return 0;
1050 
1051 	for_each_available_child_of_node_scoped(desc_np, child_np) {
1052 		struct device_node *child_req_np __free(device_node) =
1053 			of_parse_phandle(child_np, "required-opps", 0);
1054 
1055 		if (child_req_np == ref_np) {
1056 			u64 rate = 0;
1057 
1058 			of_property_read_u64(child_np, "opp-hz", &rate);
1059 			return (unsigned long) rate;
1060 		}
1061 	}
1062 
1063 	return 0;
1064 }
1065 
1066 static int cpr_corner_init(struct cpr_drv *drv)
1067 {
1068 	const struct cpr_desc *desc = drv->desc;
1069 	const struct cpr_fuse *fuses = drv->cpr_fuses;
1070 	int i, level, scaling = 0;
1071 	unsigned int fnum, fc;
1072 	const char *quot_offset;
1073 	struct fuse_corner *fuse, *prev_fuse;
1074 	struct corner *corner, *end;
1075 	struct corner_data *cdata;
1076 	const struct fuse_corner_data *fdata;
1077 	bool apply_scaling;
1078 	unsigned long freq_diff, freq_diff_mhz;
1079 	unsigned long freq;
1080 	int step_volt = regulator_get_linear_step(drv->vdd_apc);
1081 	struct dev_pm_opp *opp;
1082 
1083 	if (!step_volt)
1084 		return -EINVAL;
1085 
1086 	corner = drv->corners;
1087 	end = &corner[drv->num_corners - 1];
1088 
1089 	cdata = devm_kcalloc(drv->dev, drv->num_corners,
1090 			     sizeof(struct corner_data),
1091 			     GFP_KERNEL);
1092 	if (!cdata)
1093 		return -ENOMEM;
1094 
1095 	/*
1096 	 * Store maximum frequency for each fuse corner based on the frequency
1097 	 * plan
1098 	 */
1099 	for (level = 1; level <= drv->num_corners; level++) {
1100 		opp = dev_pm_opp_find_level_exact(&drv->pd.dev, level);
1101 		if (IS_ERR(opp))
1102 			return -EINVAL;
1103 		fc = cpr_get_fuse_corner(opp);
1104 		if (!fc) {
1105 			dev_pm_opp_put(opp);
1106 			return -EINVAL;
1107 		}
1108 		fnum = fc - 1;
1109 		freq = cpr_get_opp_hz_for_req(opp, drv->attached_cpu_dev);
1110 		if (!freq) {
1111 			dev_pm_opp_put(opp);
1112 			return -EINVAL;
1113 		}
1114 		cdata[level - 1].fuse_corner = fnum;
1115 		cdata[level - 1].freq = freq;
1116 
1117 		fuse = &drv->fuse_corners[fnum];
1118 		dev_dbg(drv->dev, "freq: %lu level: %u fuse level: %u\n",
1119 			freq, dev_pm_opp_get_level(opp) - 1, fnum);
1120 		if (freq > fuse->max_freq)
1121 			fuse->max_freq = freq;
1122 		dev_pm_opp_put(opp);
1123 	}
1124 
1125 	/*
1126 	 * Get the quotient adjustment scaling factor, according to:
1127 	 *
1128 	 * scaling = min(1000 * (QUOT(corner_N) - QUOT(corner_N-1))
1129 	 *		/ (freq(corner_N) - freq(corner_N-1)), max_factor)
1130 	 *
1131 	 * QUOT(corner_N):	quotient read from fuse for fuse corner N
1132 	 * QUOT(corner_N-1):	quotient read from fuse for fuse corner (N - 1)
1133 	 * freq(corner_N):	max frequency in MHz supported by fuse corner N
1134 	 * freq(corner_N-1):	max frequency in MHz supported by fuse corner
1135 	 *			 (N - 1)
1136 	 *
1137 	 * Then walk through the corners mapped to each fuse corner
1138 	 * and calculate the quotient adjustment for each one using the
1139 	 * following formula:
1140 	 *
1141 	 * quot_adjust = (freq_max - freq_corner) * scaling / 1000
1142 	 *
1143 	 * freq_max: max frequency in MHz supported by the fuse corner
1144 	 * freq_corner: frequency in MHz corresponding to the corner
1145 	 * scaling: calculated from above equation
1146 	 *
1147 	 *
1148 	 *     +                           +
1149 	 *     |                         v |
1150 	 *   q |           f c           o |           f c
1151 	 *   u |         c               l |         c
1152 	 *   o |       f                 t |       f
1153 	 *   t |     c                   a |     c
1154 	 *     | c f                     g | c f
1155 	 *     |                         e |
1156 	 *     +---------------            +----------------
1157 	 *       0 1 2 3 4 5 6               0 1 2 3 4 5 6
1158 	 *          corner                      corner
1159 	 *
1160 	 *    c = corner
1161 	 *    f = fuse corner
1162 	 *
1163 	 */
1164 	for (apply_scaling = false, i = 0; corner <= end; corner++, i++) {
1165 		fnum = cdata[i].fuse_corner;
1166 		fdata = &desc->cpr_fuses.fuse_corner_data[fnum];
1167 		quot_offset = fuses[fnum].quotient_offset;
1168 		fuse = &drv->fuse_corners[fnum];
1169 		if (fnum)
1170 			prev_fuse = &drv->fuse_corners[fnum - 1];
1171 		else
1172 			prev_fuse = NULL;
1173 
1174 		corner->fuse_corner = fuse;
1175 		corner->freq = cdata[i].freq;
1176 		corner->uV = fuse->uV;
1177 
1178 		if (prev_fuse && cdata[i - 1].freq == prev_fuse->max_freq) {
1179 			scaling = cpr_calculate_scaling(quot_offset, drv,
1180 							fdata, corner);
1181 			if (scaling < 0)
1182 				return scaling;
1183 
1184 			apply_scaling = true;
1185 		} else if (corner->freq == fuse->max_freq) {
1186 			/* This is a fuse corner; don't scale anything */
1187 			apply_scaling = false;
1188 		}
1189 
1190 		if (apply_scaling) {
1191 			freq_diff = fuse->max_freq - corner->freq;
1192 			freq_diff_mhz = freq_diff / 1000000;
1193 			corner->quot_adjust = scaling * freq_diff_mhz / 1000;
1194 
1195 			corner->uV = cpr_interpolate(corner, step_volt, fdata);
1196 		}
1197 
1198 		corner->max_uV = fuse->max_uV;
1199 		corner->min_uV = fuse->min_uV;
1200 		corner->uV = clamp(corner->uV, corner->min_uV, corner->max_uV);
1201 		corner->last_uV = corner->uV;
1202 
1203 		/* Reduce the ceiling voltage if needed */
1204 		if (desc->reduce_to_corner_uV && corner->uV < corner->max_uV)
1205 			corner->max_uV = corner->uV;
1206 		else if (desc->reduce_to_fuse_uV && fuse->uV < corner->max_uV)
1207 			corner->max_uV = max(corner->min_uV, fuse->uV);
1208 
1209 		dev_dbg(drv->dev, "corner %d: [%d %d %d] quot %d\n", i,
1210 			corner->min_uV, corner->uV, corner->max_uV,
1211 			fuse->quot - corner->quot_adjust);
1212 	}
1213 
1214 	return 0;
1215 }
1216 
1217 static const struct cpr_fuse *cpr_get_fuses(struct cpr_drv *drv)
1218 {
1219 	const struct cpr_desc *desc = drv->desc;
1220 	struct cpr_fuse *fuses;
1221 	int i;
1222 
1223 	fuses = devm_kcalloc(drv->dev, desc->num_fuse_corners,
1224 			     sizeof(struct cpr_fuse),
1225 			     GFP_KERNEL);
1226 	if (!fuses)
1227 		return ERR_PTR(-ENOMEM);
1228 
1229 	for (i = 0; i < desc->num_fuse_corners; i++) {
1230 		char tbuf[32];
1231 
1232 		snprintf(tbuf, 32, "cpr_ring_osc%d", i + 1);
1233 		fuses[i].ring_osc = devm_kstrdup(drv->dev, tbuf, GFP_KERNEL);
1234 		if (!fuses[i].ring_osc)
1235 			return ERR_PTR(-ENOMEM);
1236 
1237 		snprintf(tbuf, 32, "cpr_init_voltage%d", i + 1);
1238 		fuses[i].init_voltage = devm_kstrdup(drv->dev, tbuf,
1239 						     GFP_KERNEL);
1240 		if (!fuses[i].init_voltage)
1241 			return ERR_PTR(-ENOMEM);
1242 
1243 		snprintf(tbuf, 32, "cpr_quotient%d", i + 1);
1244 		fuses[i].quotient = devm_kstrdup(drv->dev, tbuf, GFP_KERNEL);
1245 		if (!fuses[i].quotient)
1246 			return ERR_PTR(-ENOMEM);
1247 
1248 		snprintf(tbuf, 32, "cpr_quotient_offset%d", i + 1);
1249 		fuses[i].quotient_offset = devm_kstrdup(drv->dev, tbuf,
1250 							GFP_KERNEL);
1251 		if (!fuses[i].quotient_offset)
1252 			return ERR_PTR(-ENOMEM);
1253 	}
1254 
1255 	return fuses;
1256 }
1257 
1258 static void cpr_set_loop_allowed(struct cpr_drv *drv)
1259 {
1260 	drv->loop_disabled = false;
1261 }
1262 
1263 static int cpr_init_parameters(struct cpr_drv *drv)
1264 {
1265 	const struct cpr_desc *desc = drv->desc;
1266 	struct clk *clk;
1267 
1268 	clk = clk_get(drv->dev, "ref");
1269 	if (IS_ERR(clk))
1270 		return PTR_ERR(clk);
1271 
1272 	drv->ref_clk_khz = clk_get_rate(clk) / 1000;
1273 	clk_put(clk);
1274 
1275 	if (desc->timer_cons_up > RBIF_TIMER_ADJ_CONS_UP_MASK ||
1276 	    desc->timer_cons_down > RBIF_TIMER_ADJ_CONS_DOWN_MASK ||
1277 	    desc->up_threshold > RBCPR_CTL_UP_THRESHOLD_MASK ||
1278 	    desc->down_threshold > RBCPR_CTL_DN_THRESHOLD_MASK ||
1279 	    desc->idle_clocks > RBCPR_STEP_QUOT_IDLE_CLK_MASK ||
1280 	    desc->clamp_timer_interval > RBIF_TIMER_ADJ_CLAMP_INT_MASK)
1281 		return -EINVAL;
1282 
1283 	dev_dbg(drv->dev, "up threshold = %u, down threshold = %u\n",
1284 		desc->up_threshold, desc->down_threshold);
1285 
1286 	return 0;
1287 }
1288 
1289 static int cpr_find_initial_corner(struct cpr_drv *drv)
1290 {
1291 	unsigned long rate;
1292 	const struct corner *end;
1293 	struct corner *iter;
1294 	unsigned int i = 0;
1295 
1296 	if (!drv->cpu_clk) {
1297 		dev_err(drv->dev, "cannot get rate from NULL clk\n");
1298 		return -EINVAL;
1299 	}
1300 
1301 	end = &drv->corners[drv->num_corners - 1];
1302 	rate = clk_get_rate(drv->cpu_clk);
1303 
1304 	/*
1305 	 * Some bootloaders set a CPU clock frequency that is not defined
1306 	 * in the OPP table. When running at an unlisted frequency,
1307 	 * cpufreq_online() will change to the OPP which has the lowest
1308 	 * frequency, at or above the unlisted frequency.
1309 	 * Since cpufreq_online() always "rounds up" in the case of an
1310 	 * unlisted frequency, this function always "rounds down" in case
1311 	 * of an unlisted frequency. That way, when cpufreq_online()
1312 	 * triggers the first ever call to cpr_set_performance_state(),
1313 	 * it will correctly determine the direction as UP.
1314 	 */
1315 	for (iter = drv->corners; iter <= end; iter++) {
1316 		if (iter->freq > rate)
1317 			break;
1318 		i++;
1319 		if (iter->freq == rate) {
1320 			drv->corner = iter;
1321 			break;
1322 		}
1323 		if (iter->freq < rate)
1324 			drv->corner = iter;
1325 	}
1326 
1327 	if (!drv->corner) {
1328 		dev_err(drv->dev, "boot up corner not found\n");
1329 		return -EINVAL;
1330 	}
1331 
1332 	dev_dbg(drv->dev, "boot up perf state: %u\n", i);
1333 
1334 	return 0;
1335 }
1336 
1337 static const struct cpr_desc qcs404_cpr_desc = {
1338 	.num_fuse_corners = 3,
1339 	.min_diff_quot = CPR_FUSE_MIN_QUOT_DIFF,
1340 	.step_quot = (int []){ 25, 25, 25, },
1341 	.timer_delay_us = 5000,
1342 	.timer_cons_up = 0,
1343 	.timer_cons_down = 2,
1344 	.up_threshold = 1,
1345 	.down_threshold = 3,
1346 	.idle_clocks = 15,
1347 	.gcnt_us = 1,
1348 	.vdd_apc_step_up_limit = 1,
1349 	.vdd_apc_step_down_limit = 1,
1350 	.cpr_fuses = {
1351 		.init_voltage_step = 8000,
1352 		.init_voltage_width = 6,
1353 		.fuse_corner_data = (struct fuse_corner_data[]){
1354 			/* fuse corner 0 */
1355 			{
1356 				.ref_uV = 1224000,
1357 				.max_uV = 1224000,
1358 				.min_uV = 1048000,
1359 				.max_volt_scale = 0,
1360 				.max_quot_scale = 0,
1361 				.quot_offset = 0,
1362 				.quot_scale = 1,
1363 				.quot_adjust = 0,
1364 				.quot_offset_scale = 5,
1365 				.quot_offset_adjust = 0,
1366 			},
1367 			/* fuse corner 1 */
1368 			{
1369 				.ref_uV = 1288000,
1370 				.max_uV = 1288000,
1371 				.min_uV = 1048000,
1372 				.max_volt_scale = 2000,
1373 				.max_quot_scale = 1400,
1374 				.quot_offset = 0,
1375 				.quot_scale = 1,
1376 				.quot_adjust = -20,
1377 				.quot_offset_scale = 5,
1378 				.quot_offset_adjust = 0,
1379 			},
1380 			/* fuse corner 2 */
1381 			{
1382 				.ref_uV = 1352000,
1383 				.max_uV = 1384000,
1384 				.min_uV = 1088000,
1385 				.max_volt_scale = 2000,
1386 				.max_quot_scale = 1400,
1387 				.quot_offset = 0,
1388 				.quot_scale = 1,
1389 				.quot_adjust = 0,
1390 				.quot_offset_scale = 5,
1391 				.quot_offset_adjust = 0,
1392 			},
1393 		},
1394 	},
1395 };
1396 
1397 static const struct acc_desc qcs404_acc_desc = {
1398 	.settings = (struct reg_sequence[]){
1399 		{ 0xb120, 0x1041040 },
1400 		{ 0xb124, 0x41 },
1401 		{ 0xb120, 0x0 },
1402 		{ 0xb124, 0x0 },
1403 		{ 0xb120, 0x0 },
1404 		{ 0xb124, 0x0 },
1405 	},
1406 	.config = (struct reg_sequence[]){
1407 		{ 0xb138, 0xff },
1408 		{ 0xb130, 0x5555 },
1409 	},
1410 	.num_regs_per_fuse = 2,
1411 };
1412 
1413 static const struct cpr_acc_desc qcs404_cpr_acc_desc = {
1414 	.cpr_desc = &qcs404_cpr_desc,
1415 	.acc_desc = &qcs404_acc_desc,
1416 };
1417 
1418 static int cpr_power_off(struct generic_pm_domain *domain)
1419 {
1420 	struct cpr_drv *drv = container_of(domain, struct cpr_drv, pd);
1421 
1422 	return cpr_disable(drv);
1423 }
1424 
1425 static int cpr_power_on(struct generic_pm_domain *domain)
1426 {
1427 	struct cpr_drv *drv = container_of(domain, struct cpr_drv, pd);
1428 
1429 	return cpr_enable(drv);
1430 }
1431 
1432 static int cpr_pd_attach_dev(struct generic_pm_domain *domain,
1433 			     struct device *dev)
1434 {
1435 	struct cpr_drv *drv = container_of(domain, struct cpr_drv, pd);
1436 	const struct acc_desc *acc_desc = drv->acc_desc;
1437 	int ret;
1438 
1439 	guard(mutex)(&drv->lock);
1440 
1441 	dev_dbg(drv->dev, "attach callback for: %s\n", dev_name(dev));
1442 
1443 	/*
1444 	 * This driver only supports scaling voltage for a CPU cluster
1445 	 * where all CPUs in the cluster share a single regulator.
1446 	 * Therefore, save the struct device pointer only for the first
1447 	 * CPU device that gets attached. There is no need to do any
1448 	 * additional initialization when further CPUs get attached.
1449 	 */
1450 	if (drv->attached_cpu_dev)
1451 		return 0;
1452 
1453 	/*
1454 	 * cpr_scale_voltage() requires the direction (if we are changing
1455 	 * to a higher or lower OPP). The first time
1456 	 * cpr_set_performance_state() is called, there is no previous
1457 	 * performance state defined. Therefore, we call
1458 	 * cpr_find_initial_corner() that gets the CPU clock frequency
1459 	 * set by the bootloader, so that we can determine the direction
1460 	 * the first time cpr_set_performance_state() is called.
1461 	 */
1462 	drv->cpu_clk = devm_clk_get(dev, NULL);
1463 	if (IS_ERR(drv->cpu_clk))
1464 		return dev_err_probe(drv->dev, PTR_ERR(drv->cpu_clk),
1465 				     "could not get cpu clk\n");
1466 
1467 	drv->attached_cpu_dev = dev;
1468 
1469 	dev_dbg(drv->dev, "using cpu clk from: %s\n",
1470 		dev_name(drv->attached_cpu_dev));
1471 
1472 	/*
1473 	 * Everything related to (virtual) corners has to be initialized
1474 	 * here, when attaching to the power domain, since we need to know
1475 	 * the maximum frequency for each fuse corner, and this is only
1476 	 * available after the cpufreq driver has attached to us.
1477 	 * The reason for this is that we need to know the highest
1478 	 * frequency associated with each fuse corner.
1479 	 */
1480 	ret = dev_pm_opp_get_opp_count(&drv->pd.dev);
1481 	if (ret < 0) {
1482 		dev_err(drv->dev, "could not get OPP count\n");
1483 		return ret;
1484 	}
1485 	drv->num_corners = ret;
1486 
1487 	if (drv->num_corners < 2) {
1488 		dev_err(drv->dev, "need at least 2 OPPs to use CPR\n");
1489 		return -EINVAL;
1490 	}
1491 
1492 	drv->corners = devm_kcalloc(drv->dev, drv->num_corners,
1493 				    sizeof(*drv->corners),
1494 				    GFP_KERNEL);
1495 	if (!drv->corners)
1496 		return -ENOMEM;
1497 
1498 	ret = cpr_corner_init(drv);
1499 	if (ret)
1500 		return ret;
1501 
1502 	cpr_set_loop_allowed(drv);
1503 
1504 	ret = cpr_init_parameters(drv);
1505 	if (ret)
1506 		return ret;
1507 
1508 	/* Configure CPR HW but keep it disabled */
1509 	ret = cpr_config(drv);
1510 	if (ret)
1511 		return ret;
1512 
1513 	ret = cpr_find_initial_corner(drv);
1514 	if (ret)
1515 		return ret;
1516 
1517 	if (acc_desc->config)
1518 		regmap_multi_reg_write(drv->tcsr, acc_desc->config,
1519 				       acc_desc->num_regs_per_fuse);
1520 
1521 	/* Enable ACC if required */
1522 	if (acc_desc->enable_mask)
1523 		regmap_update_bits(drv->tcsr, acc_desc->enable_reg,
1524 				   acc_desc->enable_mask,
1525 				   acc_desc->enable_mask);
1526 
1527 	dev_info(drv->dev, "driver initialized with %u OPPs\n",
1528 		 drv->num_corners);
1529 
1530 	return 0;
1531 }
1532 
1533 static int cpr_debug_info_show(struct seq_file *s, void *unused)
1534 {
1535 	u32 gcnt, ro_sel, ctl, irq_status, reg, error_steps;
1536 	u32 step_dn, step_up, error, error_lt0, busy;
1537 	struct cpr_drv *drv = s->private;
1538 	struct fuse_corner *fuse_corner;
1539 	struct corner *corner;
1540 
1541 	corner = drv->corner;
1542 	fuse_corner = corner->fuse_corner;
1543 
1544 	seq_printf(s, "corner, current_volt = %d uV\n",
1545 		       corner->last_uV);
1546 
1547 	ro_sel = fuse_corner->ring_osc_idx;
1548 	gcnt = cpr_read(drv, REG_RBCPR_GCNT_TARGET(ro_sel));
1549 	seq_printf(s, "rbcpr_gcnt_target (%u) = %#02X\n", ro_sel, gcnt);
1550 
1551 	ctl = cpr_read(drv, REG_RBCPR_CTL);
1552 	seq_printf(s, "rbcpr_ctl = %#02X\n", ctl);
1553 
1554 	irq_status = cpr_read(drv, REG_RBIF_IRQ_STATUS);
1555 	seq_printf(s, "rbcpr_irq_status = %#02X\n", irq_status);
1556 
1557 	reg = cpr_read(drv, REG_RBCPR_RESULT_0);
1558 	seq_printf(s, "rbcpr_result_0 = %#02X\n", reg);
1559 
1560 	step_dn = reg & 0x01;
1561 	step_up = (reg >> RBCPR_RESULT0_STEP_UP_SHIFT) & 0x01;
1562 	seq_printf(s, "  [step_dn = %u", step_dn);
1563 
1564 	seq_printf(s, ", step_up = %u", step_up);
1565 
1566 	error_steps = (reg >> RBCPR_RESULT0_ERROR_STEPS_SHIFT)
1567 				& RBCPR_RESULT0_ERROR_STEPS_MASK;
1568 	seq_printf(s, ", error_steps = %u", error_steps);
1569 
1570 	error = (reg >> RBCPR_RESULT0_ERROR_SHIFT) & RBCPR_RESULT0_ERROR_MASK;
1571 	seq_printf(s, ", error = %u", error);
1572 
1573 	error_lt0 = (reg >> RBCPR_RESULT0_ERROR_LT0_SHIFT) & 0x01;
1574 	seq_printf(s, ", error_lt_0 = %u", error_lt0);
1575 
1576 	busy = (reg >> RBCPR_RESULT0_BUSY_SHIFT) & 0x01;
1577 	seq_printf(s, ", busy = %u]\n", busy);
1578 
1579 	return 0;
1580 }
1581 DEFINE_SHOW_ATTRIBUTE(cpr_debug_info);
1582 
1583 static void cpr_debugfs_init(struct cpr_drv *drv)
1584 {
1585 	drv->debugfs = debugfs_create_dir("qcom_cpr", NULL);
1586 
1587 	debugfs_create_file("debug_info", 0444, drv->debugfs,
1588 			    drv, &cpr_debug_info_fops);
1589 }
1590 
1591 static int cpr_probe(struct platform_device *pdev)
1592 {
1593 	struct device *dev = &pdev->dev;
1594 	struct cpr_drv *drv;
1595 	int irq, ret;
1596 	const struct cpr_acc_desc *data;
1597 	struct device_node *np;
1598 	u32 cpr_rev = FUSE_REVISION_UNKNOWN;
1599 
1600 	data = of_device_get_match_data(dev);
1601 	if (!data || !data->cpr_desc || !data->acc_desc)
1602 		return -EINVAL;
1603 
1604 	drv = devm_kzalloc(dev,
1605 			struct_size(drv, fuse_corners, data->cpr_desc->num_fuse_corners),
1606 			GFP_KERNEL);
1607 	if (!drv)
1608 		return -ENOMEM;
1609 	drv->dev = dev;
1610 	drv->desc = data->cpr_desc;
1611 	drv->acc_desc = data->acc_desc;
1612 
1613 	np = of_parse_phandle(dev->of_node, "acc-syscon", 0);
1614 	if (!np)
1615 		return -ENODEV;
1616 
1617 	drv->tcsr = syscon_node_to_regmap(np);
1618 	of_node_put(np);
1619 	if (IS_ERR(drv->tcsr))
1620 		return PTR_ERR(drv->tcsr);
1621 
1622 	drv->base = devm_platform_ioremap_resource(pdev, 0);
1623 	if (IS_ERR(drv->base))
1624 		return PTR_ERR(drv->base);
1625 
1626 	irq = platform_get_irq(pdev, 0);
1627 	if (irq < 0)
1628 		return -EINVAL;
1629 
1630 	drv->vdd_apc = devm_regulator_get(dev, "vdd-apc");
1631 	if (IS_ERR(drv->vdd_apc))
1632 		return PTR_ERR(drv->vdd_apc);
1633 
1634 	/*
1635 	 * Initialize fuse corners, since it simply depends
1636 	 * on data in efuses.
1637 	 * Everything related to (virtual) corners has to be
1638 	 * initialized after attaching to the power domain,
1639 	 * since it depends on the CPU's OPP table.
1640 	 */
1641 	ret = nvmem_cell_read_variable_le_u32(dev, "cpr_fuse_revision", &cpr_rev);
1642 	if (ret)
1643 		return ret;
1644 
1645 	drv->cpr_fuses = cpr_get_fuses(drv);
1646 	if (IS_ERR(drv->cpr_fuses))
1647 		return PTR_ERR(drv->cpr_fuses);
1648 
1649 	ret = cpr_populate_ring_osc_idx(drv);
1650 	if (ret)
1651 		return ret;
1652 
1653 	ret = cpr_fuse_corner_init(drv);
1654 	if (ret)
1655 		return ret;
1656 
1657 	mutex_init(&drv->lock);
1658 
1659 	ret = devm_request_threaded_irq(dev, irq, NULL,
1660 					cpr_irq_handler,
1661 					IRQF_ONESHOT | IRQF_TRIGGER_RISING,
1662 					"cpr", drv);
1663 	if (ret)
1664 		return ret;
1665 
1666 	drv->pd.name = devm_kstrdup_const(dev, dev->of_node->full_name,
1667 					  GFP_KERNEL);
1668 	if (!drv->pd.name)
1669 		return -EINVAL;
1670 
1671 	drv->pd.power_off = cpr_power_off;
1672 	drv->pd.power_on = cpr_power_on;
1673 	drv->pd.set_performance_state = cpr_set_performance_state;
1674 	drv->pd.attach_dev = cpr_pd_attach_dev;
1675 
1676 	ret = pm_genpd_init(&drv->pd, NULL, true);
1677 	if (ret)
1678 		return ret;
1679 
1680 	ret = of_genpd_add_provider_simple(dev->of_node, &drv->pd);
1681 	if (ret)
1682 		goto err_remove_genpd;
1683 
1684 	platform_set_drvdata(pdev, drv);
1685 	cpr_debugfs_init(drv);
1686 
1687 	return 0;
1688 
1689 err_remove_genpd:
1690 	pm_genpd_remove(&drv->pd);
1691 	return ret;
1692 }
1693 
1694 static void cpr_remove(struct platform_device *pdev)
1695 {
1696 	struct cpr_drv *drv = platform_get_drvdata(pdev);
1697 
1698 	if (cpr_is_allowed(drv)) {
1699 		cpr_ctl_disable(drv);
1700 		cpr_irq_set(drv, 0);
1701 	}
1702 
1703 	of_genpd_del_provider(pdev->dev.of_node);
1704 	pm_genpd_remove(&drv->pd);
1705 
1706 	debugfs_remove_recursive(drv->debugfs);
1707 }
1708 
1709 static const struct of_device_id cpr_match_table[] = {
1710 	{ .compatible = "qcom,qcs404-cpr", .data = &qcs404_cpr_acc_desc },
1711 	{ }
1712 };
1713 MODULE_DEVICE_TABLE(of, cpr_match_table);
1714 
1715 static struct platform_driver cpr_driver = {
1716 	.probe		= cpr_probe,
1717 	.remove		= cpr_remove,
1718 	.driver		= {
1719 		.name	= "qcom-cpr",
1720 		.of_match_table = cpr_match_table,
1721 	},
1722 };
1723 module_platform_driver(cpr_driver);
1724 
1725 MODULE_DESCRIPTION("Core Power Reduction (CPR) driver");
1726 MODULE_LICENSE("GPL v2");
1727