1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Texas Instruments SoC Adaptive Body Bias(ABB) Regulator
4  *
5  * Copyright (C) 2011 Texas Instruments, Inc.
6  * Mike Turquette <mturquette@ti.com>
7  *
8  * Copyright (C) 2012-2013 Texas Instruments, Inc.
9  * Andrii Tseglytskyi <andrii.tseglytskyi@ti.com>
10  * Nishanth Menon <nm@ti.com>
11  */
12 #include <linux/clk.h>
13 #include <linux/delay.h>
14 #include <linux/err.h>
15 #include <linux/io.h>
16 #include <linux/module.h>
17 #include <linux/of.h>
18 #include <linux/platform_device.h>
19 #include <linux/regulator/driver.h>
20 #include <linux/regulator/machine.h>
21 #include <linux/regulator/of_regulator.h>
22 
23 /*
24  * ABB LDO operating states:
25  * NOMINAL_OPP:	bypasses the ABB LDO
26  * FAST_OPP:	sets ABB LDO to Forward Body-Bias
27  * SLOW_OPP:	sets ABB LDO to Reverse Body-Bias
28  */
29 #define TI_ABB_NOMINAL_OPP	0
30 #define TI_ABB_FAST_OPP		1
31 #define TI_ABB_SLOW_OPP		3
32 
33 /**
34  * struct ti_abb_info - ABB information per voltage setting
35  * @opp_sel:	one of TI_ABB macro
36  * @vset:	(optional) vset value that LDOVBB needs to be overridden with.
37  *
38  * Array of per voltage entries organized in the same order as regulator_desc's
39  * volt_table list. (selector is used to index from this array)
40  */
41 struct ti_abb_info {
42 	u32 opp_sel;
43 	u32 vset;
44 };
45 
46 /**
47  * struct ti_abb_reg - Register description for ABB block
48  * @setup_off:			setup register offset from base
49  * @control_off:		control register offset from base
50  * @sr2_wtcnt_value_mask:	setup register- sr2_wtcnt_value mask
51  * @fbb_sel_mask:		setup register- FBB sel mask
52  * @rbb_sel_mask:		setup register- RBB sel mask
53  * @sr2_en_mask:		setup register- enable mask
54  * @opp_change_mask:		control register - mask to trigger LDOVBB change
55  * @opp_sel_mask:		control register - mask for mode to operate
56  */
57 struct ti_abb_reg {
58 	u32 setup_off;
59 	u32 control_off;
60 
61 	/* Setup register fields */
62 	u32 sr2_wtcnt_value_mask;
63 	u32 fbb_sel_mask;
64 	u32 rbb_sel_mask;
65 	u32 sr2_en_mask;
66 
67 	/* Control register fields */
68 	u32 opp_change_mask;
69 	u32 opp_sel_mask;
70 };
71 
72 /**
73  * struct ti_abb - ABB instance data
74  * @rdesc:			regulator descriptor
75  * @clk:			clock(usually sysclk) supplying ABB block
76  * @base:			base address of ABB block
77  * @setup_reg:			setup register of ABB block
78  * @control_reg:		control register of ABB block
79  * @int_base:			interrupt register base address
80  * @efuse_base:			(optional) efuse base address for ABB modes
81  * @ldo_base:			(optional) LDOVBB vset override base address
82  * @regs:			pointer to struct ti_abb_reg for ABB block
83  * @txdone_mask:		mask on int_base for tranxdone interrupt
84  * @ldovbb_override_mask:	mask to ldo_base for overriding default LDO VBB
85  *				vset with value from efuse
86  * @ldovbb_vset_mask:		mask to ldo_base for providing the VSET override
87  * @info:			array to per voltage ABB configuration
88  * @current_info_idx:		current index to info
89  * @settling_time:		SoC specific settling time for LDO VBB
90  */
91 struct ti_abb {
92 	struct regulator_desc rdesc;
93 	struct clk *clk;
94 	void __iomem *base;
95 	void __iomem *setup_reg;
96 	void __iomem *control_reg;
97 	void __iomem *int_base;
98 	void __iomem *efuse_base;
99 	void __iomem *ldo_base;
100 
101 	const struct ti_abb_reg *regs;
102 	u32 txdone_mask;
103 	u32 ldovbb_override_mask;
104 	u32 ldovbb_vset_mask;
105 
106 	struct ti_abb_info *info;
107 	int current_info_idx;
108 
109 	u32 settling_time;
110 };
111 
112 /**
113  * ti_abb_rmw() - handy wrapper to set specific register bits
114  * @mask:	mask for register field
115  * @value:	value shifted to mask location and written
116  * @reg:	register address
117  *
118  * Return: final register value (may be unused)
119  */
ti_abb_rmw(u32 mask,u32 value,void __iomem * reg)120 static inline u32 ti_abb_rmw(u32 mask, u32 value, void __iomem *reg)
121 {
122 	u32 val;
123 
124 	val = readl(reg);
125 	val &= ~mask;
126 	val |= (value << __ffs(mask)) & mask;
127 	writel(val, reg);
128 
129 	return val;
130 }
131 
132 /**
133  * ti_abb_check_txdone() - handy wrapper to check ABB tranxdone status
134  * @abb:	pointer to the abb instance
135  *
136  * Return: true or false
137  */
ti_abb_check_txdone(const struct ti_abb * abb)138 static inline bool ti_abb_check_txdone(const struct ti_abb *abb)
139 {
140 	return !!(readl(abb->int_base) & abb->txdone_mask);
141 }
142 
143 /**
144  * ti_abb_clear_txdone() - handy wrapper to clear ABB tranxdone status
145  * @abb:	pointer to the abb instance
146  */
ti_abb_clear_txdone(const struct ti_abb * abb)147 static inline void ti_abb_clear_txdone(const struct ti_abb *abb)
148 {
149 	writel(abb->txdone_mask, abb->int_base);
150 };
151 
152 /**
153  * ti_abb_wait_txdone() - waits for ABB tranxdone event
154  * @dev:	device
155  * @abb:	pointer to the abb instance
156  *
157  * Return: 0 on success or -ETIMEDOUT if the event is not cleared on time.
158  */
ti_abb_wait_txdone(struct device * dev,struct ti_abb * abb)159 static int ti_abb_wait_txdone(struct device *dev, struct ti_abb *abb)
160 {
161 	int timeout = 0;
162 	bool status;
163 
164 	while (timeout++ <= abb->settling_time) {
165 		status = ti_abb_check_txdone(abb);
166 		if (status)
167 			return 0;
168 
169 		udelay(1);
170 	}
171 
172 	dev_warn_ratelimited(dev, "%s:TRANXDONE timeout(%duS) int=0x%08x\n",
173 			     __func__, timeout, readl(abb->int_base));
174 	return -ETIMEDOUT;
175 }
176 
177 /**
178  * ti_abb_clear_all_txdone() - clears ABB tranxdone event
179  * @dev:	device
180  * @abb:	pointer to the abb instance
181  *
182  * Return: 0 on success or -ETIMEDOUT if the event is not cleared on time.
183  */
ti_abb_clear_all_txdone(struct device * dev,const struct ti_abb * abb)184 static int ti_abb_clear_all_txdone(struct device *dev, const struct ti_abb *abb)
185 {
186 	int timeout = 0;
187 	bool status;
188 
189 	while (timeout++ <= abb->settling_time) {
190 		ti_abb_clear_txdone(abb);
191 
192 		status = ti_abb_check_txdone(abb);
193 		if (!status)
194 			return 0;
195 
196 		udelay(1);
197 	}
198 
199 	dev_warn_ratelimited(dev, "%s:TRANXDONE timeout(%duS) int=0x%08x\n",
200 			     __func__, timeout, readl(abb->int_base));
201 	return -ETIMEDOUT;
202 }
203 
204 /**
205  * ti_abb_program_ldovbb() - program LDOVBB register for override value
206  * @dev:	device
207  * @abb:	pointer to the abb instance
208  * @info:	ABB info to program
209  */
ti_abb_program_ldovbb(struct device * dev,const struct ti_abb * abb,struct ti_abb_info * info)210 static void ti_abb_program_ldovbb(struct device *dev, const struct ti_abb *abb,
211 				  struct ti_abb_info *info)
212 {
213 	u32 val;
214 
215 	val = readl(abb->ldo_base);
216 	/* clear up previous values */
217 	val &= ~(abb->ldovbb_override_mask | abb->ldovbb_vset_mask);
218 
219 	switch (info->opp_sel) {
220 	case TI_ABB_SLOW_OPP:
221 	case TI_ABB_FAST_OPP:
222 		val |= abb->ldovbb_override_mask;
223 		val |= info->vset << __ffs(abb->ldovbb_vset_mask);
224 		break;
225 	}
226 
227 	writel(val, abb->ldo_base);
228 }
229 
230 /**
231  * ti_abb_set_opp() - Setup ABB and LDO VBB for required bias
232  * @rdev:	regulator device
233  * @abb:	pointer to the abb instance
234  * @info:	ABB info to program
235  *
236  * Return: 0 on success or appropriate error value when fails
237  */
ti_abb_set_opp(struct regulator_dev * rdev,struct ti_abb * abb,struct ti_abb_info * info)238 static int ti_abb_set_opp(struct regulator_dev *rdev, struct ti_abb *abb,
239 			  struct ti_abb_info *info)
240 {
241 	const struct ti_abb_reg *regs = abb->regs;
242 	struct device *dev = &rdev->dev;
243 	int ret;
244 
245 	ret = ti_abb_clear_all_txdone(dev, abb);
246 	if (ret)
247 		goto out;
248 
249 	ti_abb_rmw(regs->fbb_sel_mask | regs->rbb_sel_mask, 0, abb->setup_reg);
250 
251 	switch (info->opp_sel) {
252 	case TI_ABB_SLOW_OPP:
253 		ti_abb_rmw(regs->rbb_sel_mask, 1, abb->setup_reg);
254 		break;
255 	case TI_ABB_FAST_OPP:
256 		ti_abb_rmw(regs->fbb_sel_mask, 1, abb->setup_reg);
257 		break;
258 	}
259 
260 	/* program next state of ABB ldo */
261 	ti_abb_rmw(regs->opp_sel_mask, info->opp_sel, abb->control_reg);
262 
263 	/*
264 	 * program LDO VBB vset override if needed for !bypass mode
265 	 * XXX: Do not switch sequence - for !bypass, LDO override reset *must*
266 	 * be performed *before* switch to bias mode else VBB glitches.
267 	 */
268 	if (abb->ldo_base && info->opp_sel != TI_ABB_NOMINAL_OPP)
269 		ti_abb_program_ldovbb(dev, abb, info);
270 
271 	/* Initiate ABB ldo change */
272 	ti_abb_rmw(regs->opp_change_mask, 1, abb->control_reg);
273 
274 	/* Wait for ABB LDO to complete transition to new Bias setting */
275 	ret = ti_abb_wait_txdone(dev, abb);
276 	if (ret)
277 		goto out;
278 
279 	ret = ti_abb_clear_all_txdone(dev, abb);
280 	if (ret)
281 		goto out;
282 
283 	/*
284 	 * Reset LDO VBB vset override bypass mode
285 	 * XXX: Do not switch sequence - for bypass, LDO override reset *must*
286 	 * be performed *after* switch to bypass else VBB glitches.
287 	 */
288 	if (abb->ldo_base && info->opp_sel == TI_ABB_NOMINAL_OPP)
289 		ti_abb_program_ldovbb(dev, abb, info);
290 
291 out:
292 	return ret;
293 }
294 
295 /**
296  * ti_abb_set_voltage_sel() - regulator accessor function to set ABB LDO
297  * @rdev:	regulator device
298  * @sel:	selector to index into required ABB LDO settings (maps to
299  *		regulator descriptor's volt_table)
300  *
301  * Return: 0 on success or appropriate error value when fails
302  */
ti_abb_set_voltage_sel(struct regulator_dev * rdev,unsigned int sel)303 static int ti_abb_set_voltage_sel(struct regulator_dev *rdev, unsigned int sel)
304 {
305 	const struct regulator_desc *desc = rdev->desc;
306 	struct ti_abb *abb = rdev_get_drvdata(rdev);
307 	struct device *dev = &rdev->dev;
308 	struct ti_abb_info *info, *oinfo;
309 	int ret = 0;
310 
311 	if (!abb) {
312 		dev_err_ratelimited(dev, "%s: No regulator drvdata\n",
313 				    __func__);
314 		return -ENODEV;
315 	}
316 
317 	if (!desc->n_voltages || !abb->info) {
318 		dev_err_ratelimited(dev,
319 				    "%s: No valid voltage table entries?\n",
320 				    __func__);
321 		return -EINVAL;
322 	}
323 
324 	if (sel >= desc->n_voltages) {
325 		dev_err(dev, "%s: sel idx(%d) >= n_voltages(%d)\n", __func__,
326 			sel, desc->n_voltages);
327 		return -EINVAL;
328 	}
329 
330 	/* If we are in the same index as we were, nothing to do here! */
331 	if (sel == abb->current_info_idx) {
332 		dev_dbg(dev, "%s: Already at sel=%d\n", __func__, sel);
333 		return ret;
334 	}
335 
336 	info = &abb->info[sel];
337 	/*
338 	 * When Linux kernel is starting up, we aren't sure of the
339 	 * Bias configuration that bootloader has configured.
340 	 * So, we get to know the actual setting the first time
341 	 * we are asked to transition.
342 	 */
343 	if (abb->current_info_idx == -EINVAL)
344 		goto just_set_abb;
345 
346 	/* If data is exactly the same, then just update index, no change */
347 	oinfo = &abb->info[abb->current_info_idx];
348 	if (!memcmp(info, oinfo, sizeof(*info))) {
349 		dev_dbg(dev, "%s: Same data new idx=%d, old idx=%d\n", __func__,
350 			sel, abb->current_info_idx);
351 		goto out;
352 	}
353 
354 just_set_abb:
355 	ret = ti_abb_set_opp(rdev, abb, info);
356 
357 out:
358 	if (!ret)
359 		abb->current_info_idx = sel;
360 	else
361 		dev_err_ratelimited(dev,
362 				    "%s: Volt[%d] idx[%d] mode[%d] Fail(%d)\n",
363 				    __func__, desc->volt_table[sel], sel,
364 				    info->opp_sel, ret);
365 	return ret;
366 }
367 
368 /**
369  * ti_abb_get_voltage_sel() - Regulator accessor to get current ABB LDO setting
370  * @rdev:	regulator device
371  *
372  * Return: 0 on success or appropriate error value when fails
373  */
ti_abb_get_voltage_sel(struct regulator_dev * rdev)374 static int ti_abb_get_voltage_sel(struct regulator_dev *rdev)
375 {
376 	const struct regulator_desc *desc = rdev->desc;
377 	struct ti_abb *abb = rdev_get_drvdata(rdev);
378 	struct device *dev = &rdev->dev;
379 
380 	if (!abb) {
381 		dev_err_ratelimited(dev, "%s: No regulator drvdata\n",
382 				    __func__);
383 		return -ENODEV;
384 	}
385 
386 	if (!desc->n_voltages || !abb->info) {
387 		dev_err_ratelimited(dev,
388 				    "%s: No valid voltage table entries?\n",
389 				    __func__);
390 		return -EINVAL;
391 	}
392 
393 	if (abb->current_info_idx >= (int)desc->n_voltages) {
394 		dev_err(dev, "%s: Corrupted data? idx(%d) >= n_voltages(%d)\n",
395 			__func__, abb->current_info_idx, desc->n_voltages);
396 		return -EINVAL;
397 	}
398 
399 	return abb->current_info_idx;
400 }
401 
402 /**
403  * ti_abb_init_timings() - setup ABB clock timing for the current platform
404  * @dev:	device
405  * @abb:	pointer to the abb instance
406  *
407  * Return: 0 if timing is updated, else returns error result.
408  */
ti_abb_init_timings(struct device * dev,struct ti_abb * abb)409 static int ti_abb_init_timings(struct device *dev, struct ti_abb *abb)
410 {
411 	u32 clock_cycles;
412 	u32 clk_rate, sr2_wt_cnt_val, cycle_rate;
413 	const struct ti_abb_reg *regs = abb->regs;
414 	int ret;
415 	char *pname = "ti,settling-time";
416 
417 	/* read device tree properties */
418 	ret = of_property_read_u32(dev->of_node, pname, &abb->settling_time);
419 	if (ret) {
420 		dev_err(dev, "Unable to get property '%s'(%d)\n", pname, ret);
421 		return ret;
422 	}
423 
424 	/* ABB LDO cannot be settle in 0 time */
425 	if (!abb->settling_time) {
426 		dev_err(dev, "Invalid property:'%s' set as 0!\n", pname);
427 		return -EINVAL;
428 	}
429 
430 	pname = "ti,clock-cycles";
431 	ret = of_property_read_u32(dev->of_node, pname, &clock_cycles);
432 	if (ret) {
433 		dev_err(dev, "Unable to get property '%s'(%d)\n", pname, ret);
434 		return ret;
435 	}
436 	/* ABB LDO cannot be settle in 0 clock cycles */
437 	if (!clock_cycles) {
438 		dev_err(dev, "Invalid property:'%s' set as 0!\n", pname);
439 		return -EINVAL;
440 	}
441 
442 	abb->clk = devm_clk_get(dev, NULL);
443 	if (IS_ERR(abb->clk)) {
444 		ret = PTR_ERR(abb->clk);
445 		dev_err(dev, "%s: Unable to get clk(%d)\n", __func__, ret);
446 		return ret;
447 	}
448 
449 	/*
450 	 * SR2_WTCNT_VALUE is the settling time for the ABB ldo after a
451 	 * transition and must be programmed with the correct time at boot.
452 	 * The value programmed into the register is the number of SYS_CLK
453 	 * clock cycles that match a given wall time profiled for the ldo.
454 	 * This value depends on:
455 	 * settling time of ldo in micro-seconds (varies per OMAP family)
456 	 * # of clock cycles per SYS_CLK period (varies per OMAP family)
457 	 * the SYS_CLK frequency in MHz (varies per board)
458 	 * The formula is:
459 	 *
460 	 *                      ldo settling time (in micro-seconds)
461 	 * SR2_WTCNT_VALUE = ------------------------------------------
462 	 *                   (# system clock cycles) * (sys_clk period)
463 	 *
464 	 * Put another way:
465 	 *
466 	 * SR2_WTCNT_VALUE = settling time / (# SYS_CLK cycles / SYS_CLK rate))
467 	 *
468 	 * To avoid dividing by zero multiply both "# clock cycles" and
469 	 * "settling time" by 10 such that the final result is the one we want.
470 	 */
471 
472 	/* Convert SYS_CLK rate to MHz & prevent divide by zero */
473 	clk_rate = DIV_ROUND_CLOSEST(clk_get_rate(abb->clk), 1000000);
474 
475 	/* Calculate cycle rate */
476 	cycle_rate = DIV_ROUND_CLOSEST(clock_cycles * 10, clk_rate);
477 
478 	/* Calculate SR2_WTCNT_VALUE */
479 	sr2_wt_cnt_val = DIV_ROUND_CLOSEST(abb->settling_time * 10, cycle_rate);
480 
481 	dev_dbg(dev, "%s: Clk_rate=%ld, sr2_cnt=0x%08x\n", __func__,
482 		clk_get_rate(abb->clk), sr2_wt_cnt_val);
483 
484 	ti_abb_rmw(regs->sr2_wtcnt_value_mask, sr2_wt_cnt_val, abb->setup_reg);
485 
486 	return 0;
487 }
488 
489 /**
490  * ti_abb_init_table() - Initialize ABB table from device tree
491  * @dev:	device
492  * @abb:	pointer to the abb instance
493  * @rinit_data:	regulator initdata
494  *
495  * Return: 0 on success or appropriate error value when fails
496  */
ti_abb_init_table(struct device * dev,struct ti_abb * abb,struct regulator_init_data * rinit_data)497 static int ti_abb_init_table(struct device *dev, struct ti_abb *abb,
498 			     struct regulator_init_data *rinit_data)
499 {
500 	struct ti_abb_info *info;
501 	const u32 num_values = 6;
502 	char *pname = "ti,abb_info";
503 	u32 i;
504 	unsigned int *volt_table;
505 	int num_entries, min_uV = INT_MAX, max_uV = 0;
506 	struct regulation_constraints *c = &rinit_data->constraints;
507 
508 	/*
509 	 * Each abb_info is a set of n-tuple, where n is num_values, consisting
510 	 * of voltage and a set of detection logic for ABB information for that
511 	 * voltage to apply.
512 	 */
513 	num_entries = of_property_count_u32_elems(dev->of_node, pname);
514 	if (num_entries < 0) {
515 		dev_err(dev, "No '%s' property?\n", pname);
516 		return num_entries;
517 	}
518 
519 	if (!num_entries || (num_entries % num_values)) {
520 		dev_err(dev, "All '%s' list entries need %d vals\n", pname,
521 			num_values);
522 		return -EINVAL;
523 	}
524 	num_entries /= num_values;
525 
526 	info = devm_kcalloc(dev, num_entries, sizeof(*info), GFP_KERNEL);
527 	if (!info)
528 		return -ENOMEM;
529 
530 	abb->info = info;
531 
532 	volt_table = devm_kcalloc(dev, num_entries, sizeof(unsigned int),
533 				  GFP_KERNEL);
534 	if (!volt_table)
535 		return -ENOMEM;
536 
537 	abb->rdesc.n_voltages = num_entries;
538 	abb->rdesc.volt_table = volt_table;
539 	/* We do not know where the OPP voltage is at the moment */
540 	abb->current_info_idx = -EINVAL;
541 
542 	for (i = 0; i < num_entries; i++, info++, volt_table++) {
543 		u32 efuse_offset, rbb_mask, fbb_mask, vset_mask;
544 		u32 efuse_val;
545 
546 		/* NOTE: num_values should equal to entries picked up here */
547 		of_property_read_u32_index(dev->of_node, pname, i * num_values,
548 					   volt_table);
549 		of_property_read_u32_index(dev->of_node, pname,
550 					   i * num_values + 1, &info->opp_sel);
551 		of_property_read_u32_index(dev->of_node, pname,
552 					   i * num_values + 2, &efuse_offset);
553 		of_property_read_u32_index(dev->of_node, pname,
554 					   i * num_values + 3, &rbb_mask);
555 		of_property_read_u32_index(dev->of_node, pname,
556 					   i * num_values + 4, &fbb_mask);
557 		of_property_read_u32_index(dev->of_node, pname,
558 					   i * num_values + 5, &vset_mask);
559 
560 		dev_dbg(dev,
561 			"[%d]v=%d ABB=%d ef=0x%x rbb=0x%x fbb=0x%x vset=0x%x\n",
562 			i, *volt_table, info->opp_sel, efuse_offset, rbb_mask,
563 			fbb_mask, vset_mask);
564 
565 		/* Find min/max for voltage set */
566 		if (min_uV > *volt_table)
567 			min_uV = *volt_table;
568 		if (max_uV < *volt_table)
569 			max_uV = *volt_table;
570 
571 		if (!abb->efuse_base) {
572 			/* Ignore invalid data, but warn to help cleanup */
573 			if (efuse_offset || rbb_mask || fbb_mask || vset_mask)
574 				dev_err(dev, "prop '%s': v=%d,bad efuse/mask\n",
575 					pname, *volt_table);
576 			goto check_abb;
577 		}
578 
579 		efuse_val = readl(abb->efuse_base + efuse_offset);
580 
581 		/* Use ABB recommendation from Efuse */
582 		if (efuse_val & rbb_mask)
583 			info->opp_sel = TI_ABB_SLOW_OPP;
584 		else if (efuse_val & fbb_mask)
585 			info->opp_sel = TI_ABB_FAST_OPP;
586 		else if (rbb_mask || fbb_mask)
587 			info->opp_sel = TI_ABB_NOMINAL_OPP;
588 
589 		dev_dbg(dev,
590 			"[%d]v=%d efusev=0x%x final ABB=%d\n",
591 			i, *volt_table, efuse_val, info->opp_sel);
592 
593 		/* Use recommended Vset bits from Efuse */
594 		if (!abb->ldo_base) {
595 			if (vset_mask)
596 				dev_err(dev, "prop'%s':v=%d vst=%x LDO base?\n",
597 					pname, *volt_table, vset_mask);
598 			continue;
599 		}
600 		info->vset = (efuse_val & vset_mask) >> __ffs(vset_mask);
601 		dev_dbg(dev, "[%d]v=%d vset=%x\n", i, *volt_table, info->vset);
602 check_abb:
603 		switch (info->opp_sel) {
604 		case TI_ABB_NOMINAL_OPP:
605 		case TI_ABB_FAST_OPP:
606 		case TI_ABB_SLOW_OPP:
607 			/* Valid values */
608 			break;
609 		default:
610 			dev_err(dev, "%s:[%d]v=%d, ABB=%d is invalid! Abort!\n",
611 				__func__, i, *volt_table, info->opp_sel);
612 			return -EINVAL;
613 		}
614 	}
615 
616 	/* Setup the min/max voltage constraints from the supported list */
617 	c->min_uV = min_uV;
618 	c->max_uV = max_uV;
619 
620 	return 0;
621 }
622 
623 static const struct regulator_ops ti_abb_reg_ops = {
624 	.list_voltage = regulator_list_voltage_table,
625 
626 	.set_voltage_sel = ti_abb_set_voltage_sel,
627 	.get_voltage_sel = ti_abb_get_voltage_sel,
628 };
629 
630 /* Default ABB block offsets, IF this changes in future, create new one */
631 static const struct ti_abb_reg abb_regs_v1 = {
632 	/* WARNING: registers are wrongly documented in TRM */
633 	.setup_off		= 0x04,
634 	.control_off		= 0x00,
635 
636 	.sr2_wtcnt_value_mask	= (0xff << 8),
637 	.fbb_sel_mask		= (0x01 << 2),
638 	.rbb_sel_mask		= (0x01 << 1),
639 	.sr2_en_mask		= (0x01 << 0),
640 
641 	.opp_change_mask	= (0x01 << 2),
642 	.opp_sel_mask		= (0x03 << 0),
643 };
644 
645 static const struct ti_abb_reg abb_regs_v2 = {
646 	.setup_off		= 0x00,
647 	.control_off		= 0x04,
648 
649 	.sr2_wtcnt_value_mask	= (0xff << 8),
650 	.fbb_sel_mask		= (0x01 << 2),
651 	.rbb_sel_mask		= (0x01 << 1),
652 	.sr2_en_mask		= (0x01 << 0),
653 
654 	.opp_change_mask	= (0x01 << 2),
655 	.opp_sel_mask		= (0x03 << 0),
656 };
657 
658 static const struct ti_abb_reg abb_regs_generic = {
659 	.sr2_wtcnt_value_mask	= (0xff << 8),
660 	.fbb_sel_mask		= (0x01 << 2),
661 	.rbb_sel_mask		= (0x01 << 1),
662 	.sr2_en_mask		= (0x01 << 0),
663 
664 	.opp_change_mask	= (0x01 << 2),
665 	.opp_sel_mask		= (0x03 << 0),
666 };
667 
668 static const struct of_device_id ti_abb_of_match[] = {
669 	{.compatible = "ti,abb-v1", .data = &abb_regs_v1},
670 	{.compatible = "ti,abb-v2", .data = &abb_regs_v2},
671 	{.compatible = "ti,abb-v3", .data = &abb_regs_generic},
672 	{ },
673 };
674 
675 MODULE_DEVICE_TABLE(of, ti_abb_of_match);
676 
677 /**
678  * ti_abb_probe() - Initialize an ABB ldo instance
679  * @pdev: ABB platform device
680  *
681  * Initializes an individual ABB LDO for required Body-Bias. ABB is used to
682  * additional bias supply to SoC modules for power savings or mandatory stability
683  * configuration at certain Operating Performance Points(OPPs).
684  *
685  * Return: 0 on success or appropriate error value when fails
686  */
ti_abb_probe(struct platform_device * pdev)687 static int ti_abb_probe(struct platform_device *pdev)
688 {
689 	struct device *dev = &pdev->dev;
690 	struct resource *res;
691 	struct ti_abb *abb;
692 	struct regulator_init_data *initdata = NULL;
693 	struct regulator_dev *rdev = NULL;
694 	struct regulator_desc *desc;
695 	struct regulation_constraints *c;
696 	struct regulator_config config = { };
697 	char *pname;
698 	int ret = 0;
699 
700 	abb = devm_kzalloc(dev, sizeof(struct ti_abb), GFP_KERNEL);
701 	if (!abb)
702 		return -ENOMEM;
703 
704 	abb->regs = device_get_match_data(dev);
705 	if (!abb->regs) {
706 		dev_err(dev, "%s: Bad data in match\n", __func__);
707 		return -EINVAL;
708 	}
709 
710 	/* Map ABB resources */
711 	if (abb->regs->setup_off || abb->regs->control_off) {
712 		abb->base = devm_platform_ioremap_resource_byname(pdev, "base-address");
713 		if (IS_ERR(abb->base))
714 			return PTR_ERR(abb->base);
715 
716 		abb->setup_reg = abb->base + abb->regs->setup_off;
717 		abb->control_reg = abb->base + abb->regs->control_off;
718 
719 	} else {
720 		abb->control_reg = devm_platform_ioremap_resource_byname(pdev, "control-address");
721 		if (IS_ERR(abb->control_reg))
722 			return PTR_ERR(abb->control_reg);
723 
724 		abb->setup_reg = devm_platform_ioremap_resource_byname(pdev, "setup-address");
725 		if (IS_ERR(abb->setup_reg))
726 			return PTR_ERR(abb->setup_reg);
727 	}
728 
729 	pname = "int-address";
730 	res = platform_get_resource_byname(pdev, IORESOURCE_MEM, pname);
731 	if (!res) {
732 		dev_err(dev, "Missing '%s' IO resource\n", pname);
733 		return -ENODEV;
734 	}
735 	/*
736 	 * The MPU interrupt status register (PRM_IRQSTATUS_MPU) is
737 	 * shared between regulator-abb-{ivahd,dspeve,gpu} driver
738 	 * instances. Therefore use devm_ioremap() rather than
739 	 * devm_platform_ioremap_resource_byname() to avoid busy
740 	 * resource region conflicts.
741 	 */
742 	abb->int_base = devm_ioremap(dev, res->start,
743 					     resource_size(res));
744 	if (!abb->int_base) {
745 		dev_err(dev, "Unable to map '%s'\n", pname);
746 		return -ENOMEM;
747 	}
748 
749 	/* Map Optional resources */
750 	pname = "efuse-address";
751 	res = platform_get_resource_byname(pdev, IORESOURCE_MEM, pname);
752 	if (!res) {
753 		dev_dbg(dev, "Missing '%s' IO resource\n", pname);
754 		ret = -ENODEV;
755 		goto skip_opt;
756 	}
757 
758 	/*
759 	 * We may have shared efuse register offsets which are read-only
760 	 * between domains
761 	 */
762 	abb->efuse_base = devm_ioremap(dev, res->start,
763 					       resource_size(res));
764 	if (!abb->efuse_base) {
765 		dev_err(dev, "Unable to map '%s'\n", pname);
766 		return -ENOMEM;
767 	}
768 
769 	pname = "ldo-address";
770 	res = platform_get_resource_byname(pdev, IORESOURCE_MEM, pname);
771 	if (!res) {
772 		dev_dbg(dev, "Missing '%s' IO resource\n", pname);
773 		ret = -ENODEV;
774 		goto skip_opt;
775 	}
776 	abb->ldo_base = devm_ioremap_resource(dev, res);
777 	if (IS_ERR(abb->ldo_base))
778 		return PTR_ERR(abb->ldo_base);
779 
780 	/* IF ldo_base is set, the following are mandatory */
781 	pname = "ti,ldovbb-override-mask";
782 	ret =
783 	    of_property_read_u32(pdev->dev.of_node, pname,
784 				 &abb->ldovbb_override_mask);
785 	if (ret) {
786 		dev_err(dev, "Missing '%s' (%d)\n", pname, ret);
787 		return ret;
788 	}
789 	if (!abb->ldovbb_override_mask) {
790 		dev_err(dev, "Invalid property:'%s' set as 0!\n", pname);
791 		return -EINVAL;
792 	}
793 
794 	pname = "ti,ldovbb-vset-mask";
795 	ret =
796 	    of_property_read_u32(pdev->dev.of_node, pname,
797 				 &abb->ldovbb_vset_mask);
798 	if (ret) {
799 		dev_err(dev, "Missing '%s' (%d)\n", pname, ret);
800 		return ret;
801 	}
802 	if (!abb->ldovbb_vset_mask) {
803 		dev_err(dev, "Invalid property:'%s' set as 0!\n", pname);
804 		return -EINVAL;
805 	}
806 
807 skip_opt:
808 	pname = "ti,tranxdone-status-mask";
809 	ret =
810 	    of_property_read_u32(pdev->dev.of_node, pname,
811 				 &abb->txdone_mask);
812 	if (ret) {
813 		dev_err(dev, "Missing '%s' (%d)\n", pname, ret);
814 		return ret;
815 	}
816 	if (!abb->txdone_mask) {
817 		dev_err(dev, "Invalid property:'%s' set as 0!\n", pname);
818 		return -EINVAL;
819 	}
820 
821 	initdata = of_get_regulator_init_data(dev, pdev->dev.of_node,
822 					      &abb->rdesc);
823 	if (!initdata) {
824 		dev_err(dev, "%s: Unable to alloc regulator init data\n",
825 			__func__);
826 		return -ENOMEM;
827 	}
828 
829 	/* init ABB opp_sel table */
830 	ret = ti_abb_init_table(dev, abb, initdata);
831 	if (ret)
832 		return ret;
833 
834 	/* init ABB timing */
835 	ret = ti_abb_init_timings(dev, abb);
836 	if (ret)
837 		return ret;
838 
839 	desc = &abb->rdesc;
840 	desc->name = dev_name(dev);
841 	desc->owner = THIS_MODULE;
842 	desc->type = REGULATOR_VOLTAGE;
843 	desc->ops = &ti_abb_reg_ops;
844 
845 	c = &initdata->constraints;
846 	if (desc->n_voltages > 1)
847 		c->valid_ops_mask |= REGULATOR_CHANGE_VOLTAGE;
848 	c->always_on = true;
849 
850 	config.dev = dev;
851 	config.init_data = initdata;
852 	config.driver_data = abb;
853 	config.of_node = pdev->dev.of_node;
854 
855 	rdev = devm_regulator_register(dev, desc, &config);
856 	if (IS_ERR(rdev)) {
857 		ret = PTR_ERR(rdev);
858 		dev_err(dev, "%s: failed to register regulator(%d)\n",
859 			__func__, ret);
860 		return ret;
861 	}
862 	platform_set_drvdata(pdev, rdev);
863 
864 	/* Enable the ldo if not already done by bootloader */
865 	ti_abb_rmw(abb->regs->sr2_en_mask, 1, abb->setup_reg);
866 
867 	return 0;
868 }
869 
870 MODULE_ALIAS("platform:ti_abb");
871 
872 static struct platform_driver ti_abb_driver = {
873 	.probe = ti_abb_probe,
874 	.driver = {
875 		   .name = "ti_abb",
876 		   .probe_type = PROBE_PREFER_ASYNCHRONOUS,
877 		   .of_match_table = ti_abb_of_match,
878 		   },
879 };
880 module_platform_driver(ti_abb_driver);
881 
882 MODULE_DESCRIPTION("Texas Instruments ABB LDO regulator driver");
883 MODULE_AUTHOR("Texas Instruments Inc.");
884 MODULE_LICENSE("GPL v2");
885