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