1 /*
2  * OMAP SmartReflex Voltage Control
3  *
4  * Author: Thara Gopinath	<thara@ti.com>
5  *
6  * Copyright (C) 2010 Texas Instruments, Inc.
7  * Thara Gopinath <thara@ti.com>
8  *
9  * Copyright (C) 2008 Nokia Corporation
10  * Kalle Jokiniemi
11  *
12  * Copyright (C) 2007 Texas Instruments, Inc.
13  * Lesly A M <x0080970@ti.com>
14  *
15  * This program is free software; you can redistribute it and/or modify
16  * it under the terms of the GNU General Public License version 2 as
17  * published by the Free Software Foundation.
18  */
19 
20 #include <linux/module.h>
21 #include <linux/interrupt.h>
22 #include <linux/clk.h>
23 #include <linux/io.h>
24 #include <linux/debugfs.h>
25 #include <linux/delay.h>
26 #include <linux/slab.h>
27 #include <linux/pm_runtime.h>
28 
29 #include "common.h"
30 
31 #include "pm.h"
32 #include "smartreflex.h"
33 
34 #define SMARTREFLEX_NAME_LEN	16
35 #define NVALUE_NAME_LEN		40
36 #define SR_DISABLE_TIMEOUT	200
37 
38 struct omap_sr {
39 	struct list_head		node;
40 	struct platform_device		*pdev;
41 	struct omap_sr_nvalue_table	*nvalue_table;
42 	struct voltagedomain		*voltdm;
43 	struct dentry			*dbg_dir;
44 	unsigned int			irq;
45 	int				srid;
46 	int				ip_type;
47 	int				nvalue_count;
48 	bool				autocomp_active;
49 	u32				clk_length;
50 	u32				err_weight;
51 	u32				err_minlimit;
52 	u32				err_maxlimit;
53 	u32				accum_data;
54 	u32				senn_avgweight;
55 	u32				senp_avgweight;
56 	u32				senp_mod;
57 	u32				senn_mod;
58 	void __iomem			*base;
59 };
60 
61 /* sr_list contains all the instances of smartreflex module */
62 static LIST_HEAD(sr_list);
63 
64 static struct omap_sr_class_data *sr_class;
65 static struct omap_sr_pmic_data *sr_pmic_data;
66 static struct dentry		*sr_dbg_dir;
67 
sr_write_reg(struct omap_sr * sr,unsigned offset,u32 value)68 static inline void sr_write_reg(struct omap_sr *sr, unsigned offset, u32 value)
69 {
70 	__raw_writel(value, (sr->base + offset));
71 }
72 
sr_modify_reg(struct omap_sr * sr,unsigned offset,u32 mask,u32 value)73 static inline void sr_modify_reg(struct omap_sr *sr, unsigned offset, u32 mask,
74 					u32 value)
75 {
76 	u32 reg_val;
77 
78 	/*
79 	 * Smartreflex error config register is special as it contains
80 	 * certain status bits which if written a 1 into means a clear
81 	 * of those bits. So in order to make sure no accidental write of
82 	 * 1 happens to those status bits, do a clear of them in the read
83 	 * value. This mean this API doesn't rewrite values in these bits
84 	 * if they are currently set, but does allow the caller to write
85 	 * those bits.
86 	 */
87 	if (sr->ip_type == SR_TYPE_V1 && offset == ERRCONFIG_V1)
88 		mask |= ERRCONFIG_STATUS_V1_MASK;
89 	else if (sr->ip_type == SR_TYPE_V2 && offset == ERRCONFIG_V2)
90 		mask |= ERRCONFIG_VPBOUNDINTST_V2;
91 
92 	reg_val = __raw_readl(sr->base + offset);
93 	reg_val &= ~mask;
94 
95 	value &= mask;
96 
97 	reg_val |= value;
98 
99 	__raw_writel(reg_val, (sr->base + offset));
100 }
101 
sr_read_reg(struct omap_sr * sr,unsigned offset)102 static inline u32 sr_read_reg(struct omap_sr *sr, unsigned offset)
103 {
104 	return __raw_readl(sr->base + offset);
105 }
106 
_sr_lookup(struct voltagedomain * voltdm)107 static struct omap_sr *_sr_lookup(struct voltagedomain *voltdm)
108 {
109 	struct omap_sr *sr_info;
110 
111 	if (!voltdm) {
112 		pr_err("%s: Null voltage domain passed!\n", __func__);
113 		return ERR_PTR(-EINVAL);
114 	}
115 
116 	list_for_each_entry(sr_info, &sr_list, node) {
117 		if (voltdm == sr_info->voltdm)
118 			return sr_info;
119 	}
120 
121 	return ERR_PTR(-ENODATA);
122 }
123 
sr_interrupt(int irq,void * data)124 static irqreturn_t sr_interrupt(int irq, void *data)
125 {
126 	struct omap_sr *sr_info = data;
127 	u32 status = 0;
128 
129 	switch (sr_info->ip_type) {
130 	case SR_TYPE_V1:
131 		/* Read the status bits */
132 		status = sr_read_reg(sr_info, ERRCONFIG_V1);
133 
134 		/* Clear them by writing back */
135 		sr_write_reg(sr_info, ERRCONFIG_V1, status);
136 		break;
137 	case SR_TYPE_V2:
138 		/* Read the status bits */
139 		status = sr_read_reg(sr_info, IRQSTATUS);
140 
141 		/* Clear them by writing back */
142 		sr_write_reg(sr_info, IRQSTATUS, status);
143 		break;
144 	default:
145 		dev_err(&sr_info->pdev->dev, "UNKNOWN IP type %d\n",
146 			sr_info->ip_type);
147 		return IRQ_NONE;
148 	}
149 
150 	if (sr_class->notify)
151 		sr_class->notify(sr_info->voltdm, status);
152 
153 	return IRQ_HANDLED;
154 }
155 
sr_set_clk_length(struct omap_sr * sr)156 static void sr_set_clk_length(struct omap_sr *sr)
157 {
158 	struct clk *sys_ck;
159 	u32 sys_clk_speed;
160 
161 	if (cpu_is_omap34xx())
162 		sys_ck = clk_get(NULL, "sys_ck");
163 	else
164 		sys_ck = clk_get(NULL, "sys_clkin_ck");
165 
166 	if (IS_ERR(sys_ck)) {
167 		dev_err(&sr->pdev->dev, "%s: unable to get sys clk\n",
168 			__func__);
169 		return;
170 	}
171 
172 	sys_clk_speed = clk_get_rate(sys_ck);
173 	clk_put(sys_ck);
174 
175 	switch (sys_clk_speed) {
176 	case 12000000:
177 		sr->clk_length = SRCLKLENGTH_12MHZ_SYSCLK;
178 		break;
179 	case 13000000:
180 		sr->clk_length = SRCLKLENGTH_13MHZ_SYSCLK;
181 		break;
182 	case 19200000:
183 		sr->clk_length = SRCLKLENGTH_19MHZ_SYSCLK;
184 		break;
185 	case 26000000:
186 		sr->clk_length = SRCLKLENGTH_26MHZ_SYSCLK;
187 		break;
188 	case 38400000:
189 		sr->clk_length = SRCLKLENGTH_38MHZ_SYSCLK;
190 		break;
191 	default:
192 		dev_err(&sr->pdev->dev, "%s: Invalid sysclk value: %d\n",
193 			__func__, sys_clk_speed);
194 		break;
195 	}
196 }
197 
sr_set_regfields(struct omap_sr * sr)198 static void sr_set_regfields(struct omap_sr *sr)
199 {
200 	/*
201 	 * For time being these values are defined in smartreflex.h
202 	 * and populated during init. May be they can be moved to board
203 	 * file or pmic specific data structure. In that case these structure
204 	 * fields will have to be populated using the pdata or pmic structure.
205 	 */
206 	if (cpu_is_omap34xx() || cpu_is_omap44xx()) {
207 		sr->err_weight = OMAP3430_SR_ERRWEIGHT;
208 		sr->err_maxlimit = OMAP3430_SR_ERRMAXLIMIT;
209 		sr->accum_data = OMAP3430_SR_ACCUMDATA;
210 		if (!(strcmp(sr->voltdm->name, "mpu"))) {
211 			sr->senn_avgweight = OMAP3430_SR1_SENNAVGWEIGHT;
212 			sr->senp_avgweight = OMAP3430_SR1_SENPAVGWEIGHT;
213 		} else {
214 			sr->senn_avgweight = OMAP3430_SR2_SENNAVGWEIGHT;
215 			sr->senp_avgweight = OMAP3430_SR2_SENPAVGWEIGHT;
216 		}
217 	}
218 }
219 
sr_start_vddautocomp(struct omap_sr * sr)220 static void sr_start_vddautocomp(struct omap_sr *sr)
221 {
222 	if (!sr_class || !(sr_class->enable) || !(sr_class->configure)) {
223 		dev_warn(&sr->pdev->dev,
224 			"%s: smartreflex class driver not registered\n",
225 			__func__);
226 		return;
227 	}
228 
229 	if (!sr_class->enable(sr->voltdm))
230 		sr->autocomp_active = true;
231 }
232 
sr_stop_vddautocomp(struct omap_sr * sr)233 static void sr_stop_vddautocomp(struct omap_sr *sr)
234 {
235 	if (!sr_class || !(sr_class->disable)) {
236 		dev_warn(&sr->pdev->dev,
237 			"%s: smartreflex class driver not registered\n",
238 			__func__);
239 		return;
240 	}
241 
242 	if (sr->autocomp_active) {
243 		sr_class->disable(sr->voltdm, 1);
244 		sr->autocomp_active = false;
245 	}
246 }
247 
248 /*
249  * This function handles the intializations which have to be done
250  * only when both sr device and class driver regiter has
251  * completed. This will be attempted to be called from both sr class
252  * driver register and sr device intializtion API's. Only one call
253  * will ultimately succeed.
254  *
255  * Currently this function registers interrupt handler for a particular SR
256  * if smartreflex class driver is already registered and has
257  * requested for interrupts and the SR interrupt line in present.
258  */
sr_late_init(struct omap_sr * sr_info)259 static int sr_late_init(struct omap_sr *sr_info)
260 {
261 	char *name;
262 	struct omap_sr_data *pdata = sr_info->pdev->dev.platform_data;
263 	struct resource *mem;
264 	int ret = 0;
265 
266 	if (sr_class->notify && sr_class->notify_flags && sr_info->irq) {
267 		name = kasprintf(GFP_KERNEL, "sr_%s", sr_info->voltdm->name);
268 		if (name == NULL) {
269 			ret = -ENOMEM;
270 			goto error;
271 		}
272 		ret = request_irq(sr_info->irq, sr_interrupt,
273 				0, name, sr_info);
274 		if (ret)
275 			goto error;
276 		disable_irq(sr_info->irq);
277 	}
278 
279 	if (pdata && pdata->enable_on_init)
280 		sr_start_vddautocomp(sr_info);
281 
282 	return ret;
283 
284 error:
285 	iounmap(sr_info->base);
286 	mem = platform_get_resource(sr_info->pdev, IORESOURCE_MEM, 0);
287 	release_mem_region(mem->start, resource_size(mem));
288 	list_del(&sr_info->node);
289 	dev_err(&sr_info->pdev->dev, "%s: ERROR in registering"
290 		"interrupt handler. Smartreflex will"
291 		"not function as desired\n", __func__);
292 	kfree(name);
293 	kfree(sr_info);
294 
295 	return ret;
296 }
297 
sr_v1_disable(struct omap_sr * sr)298 static void sr_v1_disable(struct omap_sr *sr)
299 {
300 	int timeout = 0;
301 	int errconf_val = ERRCONFIG_MCUACCUMINTST | ERRCONFIG_MCUVALIDINTST |
302 			ERRCONFIG_MCUBOUNDINTST;
303 
304 	/* Enable MCUDisableAcknowledge interrupt */
305 	sr_modify_reg(sr, ERRCONFIG_V1,
306 			ERRCONFIG_MCUDISACKINTEN, ERRCONFIG_MCUDISACKINTEN);
307 
308 	/* SRCONFIG - disable SR */
309 	sr_modify_reg(sr, SRCONFIG, SRCONFIG_SRENABLE, 0x0);
310 
311 	/* Disable all other SR interrupts and clear the status as needed */
312 	if (sr_read_reg(sr, ERRCONFIG_V1) & ERRCONFIG_VPBOUNDINTST_V1)
313 		errconf_val |= ERRCONFIG_VPBOUNDINTST_V1;
314 	sr_modify_reg(sr, ERRCONFIG_V1,
315 			(ERRCONFIG_MCUACCUMINTEN | ERRCONFIG_MCUVALIDINTEN |
316 			ERRCONFIG_MCUBOUNDINTEN | ERRCONFIG_VPBOUNDINTEN_V1),
317 			errconf_val);
318 
319 	/*
320 	 * Wait for SR to be disabled.
321 	 * wait until ERRCONFIG.MCUDISACKINTST = 1. Typical latency is 1us.
322 	 */
323 	omap_test_timeout((sr_read_reg(sr, ERRCONFIG_V1) &
324 			ERRCONFIG_MCUDISACKINTST), SR_DISABLE_TIMEOUT,
325 			timeout);
326 
327 	if (timeout >= SR_DISABLE_TIMEOUT)
328 		dev_warn(&sr->pdev->dev, "%s: Smartreflex disable timedout\n",
329 			__func__);
330 
331 	/* Disable MCUDisableAcknowledge interrupt & clear pending interrupt */
332 	sr_modify_reg(sr, ERRCONFIG_V1, ERRCONFIG_MCUDISACKINTEN,
333 			ERRCONFIG_MCUDISACKINTST);
334 }
335 
sr_v2_disable(struct omap_sr * sr)336 static void sr_v2_disable(struct omap_sr *sr)
337 {
338 	int timeout = 0;
339 
340 	/* Enable MCUDisableAcknowledge interrupt */
341 	sr_write_reg(sr, IRQENABLE_SET, IRQENABLE_MCUDISABLEACKINT);
342 
343 	/* SRCONFIG - disable SR */
344 	sr_modify_reg(sr, SRCONFIG, SRCONFIG_SRENABLE, 0x0);
345 
346 	/*
347 	 * Disable all other SR interrupts and clear the status
348 	 * write to status register ONLY on need basis - only if status
349 	 * is set.
350 	 */
351 	if (sr_read_reg(sr, ERRCONFIG_V2) & ERRCONFIG_VPBOUNDINTST_V2)
352 		sr_modify_reg(sr, ERRCONFIG_V2, ERRCONFIG_VPBOUNDINTEN_V2,
353 			ERRCONFIG_VPBOUNDINTST_V2);
354 	else
355 		sr_modify_reg(sr, ERRCONFIG_V2, ERRCONFIG_VPBOUNDINTEN_V2,
356 				0x0);
357 	sr_write_reg(sr, IRQENABLE_CLR, (IRQENABLE_MCUACCUMINT |
358 			IRQENABLE_MCUVALIDINT |
359 			IRQENABLE_MCUBOUNDSINT));
360 	sr_write_reg(sr, IRQSTATUS, (IRQSTATUS_MCUACCUMINT |
361 			IRQSTATUS_MCVALIDINT |
362 			IRQSTATUS_MCBOUNDSINT));
363 
364 	/*
365 	 * Wait for SR to be disabled.
366 	 * wait until IRQSTATUS.MCUDISACKINTST = 1. Typical latency is 1us.
367 	 */
368 	omap_test_timeout((sr_read_reg(sr, IRQSTATUS) &
369 			IRQSTATUS_MCUDISABLEACKINT), SR_DISABLE_TIMEOUT,
370 			timeout);
371 
372 	if (timeout >= SR_DISABLE_TIMEOUT)
373 		dev_warn(&sr->pdev->dev, "%s: Smartreflex disable timedout\n",
374 			__func__);
375 
376 	/* Disable MCUDisableAcknowledge interrupt & clear pending interrupt */
377 	sr_write_reg(sr, IRQENABLE_CLR, IRQENABLE_MCUDISABLEACKINT);
378 	sr_write_reg(sr, IRQSTATUS, IRQSTATUS_MCUDISABLEACKINT);
379 }
380 
sr_retrieve_nvalue(struct omap_sr * sr,u32 efuse_offs)381 static u32 sr_retrieve_nvalue(struct omap_sr *sr, u32 efuse_offs)
382 {
383 	int i;
384 
385 	if (!sr->nvalue_table) {
386 		dev_warn(&sr->pdev->dev, "%s: Missing ntarget value table\n",
387 			__func__);
388 		return 0;
389 	}
390 
391 	for (i = 0; i < sr->nvalue_count; i++) {
392 		if (sr->nvalue_table[i].efuse_offs == efuse_offs)
393 			return sr->nvalue_table[i].nvalue;
394 	}
395 
396 	return 0;
397 }
398 
399 /* Public Functions */
400 
401 /**
402  * sr_configure_errgen() - Configures the smrtreflex to perform AVS using the
403  *			 error generator module.
404  * @voltdm:	VDD pointer to which the SR module to be configured belongs to.
405  *
406  * This API is to be called from the smartreflex class driver to
407  * configure the error generator module inside the smartreflex module.
408  * SR settings if using the ERROR module inside Smartreflex.
409  * SR CLASS 3 by default uses only the ERROR module where as
410  * SR CLASS 2 can choose between ERROR module and MINMAXAVG
411  * module. Returns 0 on success and error value in case of failure.
412  */
sr_configure_errgen(struct voltagedomain * voltdm)413 int sr_configure_errgen(struct voltagedomain *voltdm)
414 {
415 	u32 sr_config, sr_errconfig, errconfig_offs;
416 	u32 vpboundint_en, vpboundint_st;
417 	u32 senp_en = 0, senn_en = 0;
418 	u8 senp_shift, senn_shift;
419 	struct omap_sr *sr = _sr_lookup(voltdm);
420 
421 	if (IS_ERR(sr)) {
422 		pr_warning("%s: omap_sr struct for sr_%s not found\n",
423 			__func__, voltdm->name);
424 		return PTR_ERR(sr);
425 	}
426 
427 	if (!sr->clk_length)
428 		sr_set_clk_length(sr);
429 
430 	senp_en = sr->senp_mod;
431 	senn_en = sr->senn_mod;
432 
433 	sr_config = (sr->clk_length << SRCONFIG_SRCLKLENGTH_SHIFT) |
434 		SRCONFIG_SENENABLE | SRCONFIG_ERRGEN_EN;
435 
436 	switch (sr->ip_type) {
437 	case SR_TYPE_V1:
438 		sr_config |= SRCONFIG_DELAYCTRL;
439 		senn_shift = SRCONFIG_SENNENABLE_V1_SHIFT;
440 		senp_shift = SRCONFIG_SENPENABLE_V1_SHIFT;
441 		errconfig_offs = ERRCONFIG_V1;
442 		vpboundint_en = ERRCONFIG_VPBOUNDINTEN_V1;
443 		vpboundint_st = ERRCONFIG_VPBOUNDINTST_V1;
444 		break;
445 	case SR_TYPE_V2:
446 		senn_shift = SRCONFIG_SENNENABLE_V2_SHIFT;
447 		senp_shift = SRCONFIG_SENPENABLE_V2_SHIFT;
448 		errconfig_offs = ERRCONFIG_V2;
449 		vpboundint_en = ERRCONFIG_VPBOUNDINTEN_V2;
450 		vpboundint_st = ERRCONFIG_VPBOUNDINTST_V2;
451 		break;
452 	default:
453 		dev_err(&sr->pdev->dev, "%s: Trying to Configure smartreflex"
454 			"module without specifying the ip\n", __func__);
455 		return -EINVAL;
456 	}
457 
458 	sr_config |= ((senn_en << senn_shift) | (senp_en << senp_shift));
459 	sr_write_reg(sr, SRCONFIG, sr_config);
460 	sr_errconfig = (sr->err_weight << ERRCONFIG_ERRWEIGHT_SHIFT) |
461 		(sr->err_maxlimit << ERRCONFIG_ERRMAXLIMIT_SHIFT) |
462 		(sr->err_minlimit <<  ERRCONFIG_ERRMINLIMIT_SHIFT);
463 	sr_modify_reg(sr, errconfig_offs, (SR_ERRWEIGHT_MASK |
464 		SR_ERRMAXLIMIT_MASK | SR_ERRMINLIMIT_MASK),
465 		sr_errconfig);
466 
467 	/* Enabling the interrupts if the ERROR module is used */
468 	sr_modify_reg(sr, errconfig_offs, (vpboundint_en | vpboundint_st),
469 		      vpboundint_en);
470 
471 	return 0;
472 }
473 
474 /**
475  * sr_disable_errgen() - Disables SmartReflex AVS module's errgen component
476  * @voltdm:	VDD pointer to which the SR module to be configured belongs to.
477  *
478  * This API is to be called from the smartreflex class driver to
479  * disable the error generator module inside the smartreflex module.
480  *
481  * Returns 0 on success and error value in case of failure.
482  */
sr_disable_errgen(struct voltagedomain * voltdm)483 int sr_disable_errgen(struct voltagedomain *voltdm)
484 {
485 	u32 errconfig_offs;
486 	u32 vpboundint_en, vpboundint_st;
487 	struct omap_sr *sr = _sr_lookup(voltdm);
488 
489 	if (IS_ERR(sr)) {
490 		pr_warning("%s: omap_sr struct for sr_%s not found\n",
491 			__func__, voltdm->name);
492 		return PTR_ERR(sr);
493 	}
494 
495 	switch (sr->ip_type) {
496 	case SR_TYPE_V1:
497 		errconfig_offs = ERRCONFIG_V1;
498 		vpboundint_en = ERRCONFIG_VPBOUNDINTEN_V1;
499 		vpboundint_st = ERRCONFIG_VPBOUNDINTST_V1;
500 		break;
501 	case SR_TYPE_V2:
502 		errconfig_offs = ERRCONFIG_V2;
503 		vpboundint_en = ERRCONFIG_VPBOUNDINTEN_V2;
504 		vpboundint_st = ERRCONFIG_VPBOUNDINTST_V2;
505 		break;
506 	default:
507 		dev_err(&sr->pdev->dev, "%s: Trying to Configure smartreflex"
508 			"module without specifying the ip\n", __func__);
509 		return -EINVAL;
510 	}
511 
512 	/* Disable the interrupts of ERROR module */
513 	sr_modify_reg(sr, errconfig_offs, vpboundint_en | vpboundint_st, 0);
514 
515 	/* Disable the Sensor and errorgen */
516 	sr_modify_reg(sr, SRCONFIG, SRCONFIG_SENENABLE | SRCONFIG_ERRGEN_EN, 0);
517 
518 	return 0;
519 }
520 
521 /**
522  * sr_configure_minmax() - Configures the smrtreflex to perform AVS using the
523  *			 minmaxavg module.
524  * @voltdm:	VDD pointer to which the SR module to be configured belongs to.
525  *
526  * This API is to be called from the smartreflex class driver to
527  * configure the minmaxavg module inside the smartreflex module.
528  * SR settings if using the ERROR module inside Smartreflex.
529  * SR CLASS 3 by default uses only the ERROR module where as
530  * SR CLASS 2 can choose between ERROR module and MINMAXAVG
531  * module. Returns 0 on success and error value in case of failure.
532  */
sr_configure_minmax(struct voltagedomain * voltdm)533 int sr_configure_minmax(struct voltagedomain *voltdm)
534 {
535 	u32 sr_config, sr_avgwt;
536 	u32 senp_en = 0, senn_en = 0;
537 	u8 senp_shift, senn_shift;
538 	struct omap_sr *sr = _sr_lookup(voltdm);
539 
540 	if (IS_ERR(sr)) {
541 		pr_warning("%s: omap_sr struct for sr_%s not found\n",
542 			__func__, voltdm->name);
543 		return PTR_ERR(sr);
544 	}
545 
546 	if (!sr->clk_length)
547 		sr_set_clk_length(sr);
548 
549 	senp_en = sr->senp_mod;
550 	senn_en = sr->senn_mod;
551 
552 	sr_config = (sr->clk_length << SRCONFIG_SRCLKLENGTH_SHIFT) |
553 		SRCONFIG_SENENABLE |
554 		(sr->accum_data << SRCONFIG_ACCUMDATA_SHIFT);
555 
556 	switch (sr->ip_type) {
557 	case SR_TYPE_V1:
558 		sr_config |= SRCONFIG_DELAYCTRL;
559 		senn_shift = SRCONFIG_SENNENABLE_V1_SHIFT;
560 		senp_shift = SRCONFIG_SENPENABLE_V1_SHIFT;
561 		break;
562 	case SR_TYPE_V2:
563 		senn_shift = SRCONFIG_SENNENABLE_V2_SHIFT;
564 		senp_shift = SRCONFIG_SENPENABLE_V2_SHIFT;
565 		break;
566 	default:
567 		dev_err(&sr->pdev->dev, "%s: Trying to Configure smartreflex"
568 			"module without specifying the ip\n", __func__);
569 		return -EINVAL;
570 	}
571 
572 	sr_config |= ((senn_en << senn_shift) | (senp_en << senp_shift));
573 	sr_write_reg(sr, SRCONFIG, sr_config);
574 	sr_avgwt = (sr->senp_avgweight << AVGWEIGHT_SENPAVGWEIGHT_SHIFT) |
575 		(sr->senn_avgweight << AVGWEIGHT_SENNAVGWEIGHT_SHIFT);
576 	sr_write_reg(sr, AVGWEIGHT, sr_avgwt);
577 
578 	/*
579 	 * Enabling the interrupts if MINMAXAVG module is used.
580 	 * TODO: check if all the interrupts are mandatory
581 	 */
582 	switch (sr->ip_type) {
583 	case SR_TYPE_V1:
584 		sr_modify_reg(sr, ERRCONFIG_V1,
585 			(ERRCONFIG_MCUACCUMINTEN | ERRCONFIG_MCUVALIDINTEN |
586 			ERRCONFIG_MCUBOUNDINTEN),
587 			(ERRCONFIG_MCUACCUMINTEN | ERRCONFIG_MCUACCUMINTST |
588 			 ERRCONFIG_MCUVALIDINTEN | ERRCONFIG_MCUVALIDINTST |
589 			 ERRCONFIG_MCUBOUNDINTEN | ERRCONFIG_MCUBOUNDINTST));
590 		break;
591 	case SR_TYPE_V2:
592 		sr_write_reg(sr, IRQSTATUS,
593 			IRQSTATUS_MCUACCUMINT | IRQSTATUS_MCVALIDINT |
594 			IRQSTATUS_MCBOUNDSINT | IRQSTATUS_MCUDISABLEACKINT);
595 		sr_write_reg(sr, IRQENABLE_SET,
596 			IRQENABLE_MCUACCUMINT | IRQENABLE_MCUVALIDINT |
597 			IRQENABLE_MCUBOUNDSINT | IRQENABLE_MCUDISABLEACKINT);
598 		break;
599 	default:
600 		dev_err(&sr->pdev->dev, "%s: Trying to Configure smartreflex"
601 			"module without specifying the ip\n", __func__);
602 		return -EINVAL;
603 	}
604 
605 	return 0;
606 }
607 
608 /**
609  * sr_enable() - Enables the smartreflex module.
610  * @voltdm:	VDD pointer to which the SR module to be configured belongs to.
611  * @volt:	The voltage at which the Voltage domain associated with
612  *		the smartreflex module is operating at.
613  *		This is required only to program the correct Ntarget value.
614  *
615  * This API is to be called from the smartreflex class driver to
616  * enable a smartreflex module. Returns 0 on success. Returns error
617  * value if the voltage passed is wrong or if ntarget value is wrong.
618  */
sr_enable(struct voltagedomain * voltdm,unsigned long volt)619 int sr_enable(struct voltagedomain *voltdm, unsigned long volt)
620 {
621 	struct omap_volt_data *volt_data;
622 	struct omap_sr *sr = _sr_lookup(voltdm);
623 	u32 nvalue_reciprocal;
624 	int ret;
625 
626 	if (IS_ERR(sr)) {
627 		pr_warning("%s: omap_sr struct for sr_%s not found\n",
628 			__func__, voltdm->name);
629 		return PTR_ERR(sr);
630 	}
631 
632 	volt_data = omap_voltage_get_voltdata(sr->voltdm, volt);
633 
634 	if (IS_ERR(volt_data)) {
635 		dev_warn(&sr->pdev->dev, "%s: Unable to get voltage table"
636 			"for nominal voltage %ld\n", __func__, volt);
637 		return PTR_ERR(volt_data);
638 	}
639 
640 	nvalue_reciprocal = sr_retrieve_nvalue(sr, volt_data->sr_efuse_offs);
641 
642 	if (!nvalue_reciprocal) {
643 		dev_warn(&sr->pdev->dev, "%s: NVALUE = 0 at voltage %ld\n",
644 			__func__, volt);
645 		return -ENODATA;
646 	}
647 
648 	/* errminlimit is opp dependent and hence linked to voltage */
649 	sr->err_minlimit = volt_data->sr_errminlimit;
650 
651 	pm_runtime_get_sync(&sr->pdev->dev);
652 
653 	/* Check if SR is already enabled. If yes do nothing */
654 	if (sr_read_reg(sr, SRCONFIG) & SRCONFIG_SRENABLE)
655 		return 0;
656 
657 	/* Configure SR */
658 	ret = sr_class->configure(voltdm);
659 	if (ret)
660 		return ret;
661 
662 	sr_write_reg(sr, NVALUERECIPROCAL, nvalue_reciprocal);
663 
664 	/* SRCONFIG - enable SR */
665 	sr_modify_reg(sr, SRCONFIG, SRCONFIG_SRENABLE, SRCONFIG_SRENABLE);
666 	return 0;
667 }
668 
669 /**
670  * sr_disable() - Disables the smartreflex module.
671  * @voltdm:	VDD pointer to which the SR module to be configured belongs to.
672  *
673  * This API is to be called from the smartreflex class driver to
674  * disable a smartreflex module.
675  */
sr_disable(struct voltagedomain * voltdm)676 void sr_disable(struct voltagedomain *voltdm)
677 {
678 	struct omap_sr *sr = _sr_lookup(voltdm);
679 
680 	if (IS_ERR(sr)) {
681 		pr_warning("%s: omap_sr struct for sr_%s not found\n",
682 			__func__, voltdm->name);
683 		return;
684 	}
685 
686 	/* Check if SR clocks are already disabled. If yes do nothing */
687 	if (pm_runtime_suspended(&sr->pdev->dev))
688 		return;
689 
690 	/*
691 	 * Disable SR if only it is indeed enabled. Else just
692 	 * disable the clocks.
693 	 */
694 	if (sr_read_reg(sr, SRCONFIG) & SRCONFIG_SRENABLE) {
695 		switch (sr->ip_type) {
696 		case SR_TYPE_V1:
697 			sr_v1_disable(sr);
698 			break;
699 		case SR_TYPE_V2:
700 			sr_v2_disable(sr);
701 			break;
702 		default:
703 			dev_err(&sr->pdev->dev, "UNKNOWN IP type %d\n",
704 				sr->ip_type);
705 		}
706 	}
707 
708 	pm_runtime_put_sync_suspend(&sr->pdev->dev);
709 }
710 
711 /**
712  * sr_register_class() - API to register a smartreflex class parameters.
713  * @class_data:	The structure containing various sr class specific data.
714  *
715  * This API is to be called by the smartreflex class driver to register itself
716  * with the smartreflex driver during init. Returns 0 on success else the
717  * error value.
718  */
sr_register_class(struct omap_sr_class_data * class_data)719 int sr_register_class(struct omap_sr_class_data *class_data)
720 {
721 	struct omap_sr *sr_info;
722 
723 	if (!class_data) {
724 		pr_warning("%s:, Smartreflex class data passed is NULL\n",
725 			__func__);
726 		return -EINVAL;
727 	}
728 
729 	if (sr_class) {
730 		pr_warning("%s: Smartreflex class driver already registered\n",
731 			__func__);
732 		return -EBUSY;
733 	}
734 
735 	sr_class = class_data;
736 
737 	/*
738 	 * Call into late init to do intializations that require
739 	 * both sr driver and sr class driver to be initiallized.
740 	 */
741 	list_for_each_entry(sr_info, &sr_list, node)
742 		sr_late_init(sr_info);
743 
744 	return 0;
745 }
746 
747 /**
748  * omap_sr_enable() -  API to enable SR clocks and to call into the
749  *			registered smartreflex class enable API.
750  * @voltdm:	VDD pointer to which the SR module to be configured belongs to.
751  *
752  * This API is to be called from the kernel in order to enable
753  * a particular smartreflex module. This API will do the initial
754  * configurations to turn on the smartreflex module and in turn call
755  * into the registered smartreflex class enable API.
756  */
omap_sr_enable(struct voltagedomain * voltdm)757 void omap_sr_enable(struct voltagedomain *voltdm)
758 {
759 	struct omap_sr *sr = _sr_lookup(voltdm);
760 
761 	if (IS_ERR(sr)) {
762 		pr_warning("%s: omap_sr struct for sr_%s not found\n",
763 			__func__, voltdm->name);
764 		return;
765 	}
766 
767 	if (!sr->autocomp_active)
768 		return;
769 
770 	if (!sr_class || !(sr_class->enable) || !(sr_class->configure)) {
771 		dev_warn(&sr->pdev->dev, "%s: smartreflex class driver not"
772 			"registered\n", __func__);
773 		return;
774 	}
775 
776 	sr_class->enable(voltdm);
777 }
778 
779 /**
780  * omap_sr_disable() - API to disable SR without resetting the voltage
781  *			processor voltage
782  * @voltdm:	VDD pointer to which the SR module to be configured belongs to.
783  *
784  * This API is to be called from the kernel in order to disable
785  * a particular smartreflex module. This API will in turn call
786  * into the registered smartreflex class disable API. This API will tell
787  * the smartreflex class disable not to reset the VP voltage after
788  * disabling smartreflex.
789  */
omap_sr_disable(struct voltagedomain * voltdm)790 void omap_sr_disable(struct voltagedomain *voltdm)
791 {
792 	struct omap_sr *sr = _sr_lookup(voltdm);
793 
794 	if (IS_ERR(sr)) {
795 		pr_warning("%s: omap_sr struct for sr_%s not found\n",
796 			__func__, voltdm->name);
797 		return;
798 	}
799 
800 	if (!sr->autocomp_active)
801 		return;
802 
803 	if (!sr_class || !(sr_class->disable)) {
804 		dev_warn(&sr->pdev->dev, "%s: smartreflex class driver not"
805 			"registered\n", __func__);
806 		return;
807 	}
808 
809 	sr_class->disable(voltdm, 0);
810 }
811 
812 /**
813  * omap_sr_disable_reset_volt() - API to disable SR and reset the
814  *				voltage processor voltage
815  * @voltdm:	VDD pointer to which the SR module to be configured belongs to.
816  *
817  * This API is to be called from the kernel in order to disable
818  * a particular smartreflex module. This API will in turn call
819  * into the registered smartreflex class disable API. This API will tell
820  * the smartreflex class disable to reset the VP voltage after
821  * disabling smartreflex.
822  */
omap_sr_disable_reset_volt(struct voltagedomain * voltdm)823 void omap_sr_disable_reset_volt(struct voltagedomain *voltdm)
824 {
825 	struct omap_sr *sr = _sr_lookup(voltdm);
826 
827 	if (IS_ERR(sr)) {
828 		pr_warning("%s: omap_sr struct for sr_%s not found\n",
829 			__func__, voltdm->name);
830 		return;
831 	}
832 
833 	if (!sr->autocomp_active)
834 		return;
835 
836 	if (!sr_class || !(sr_class->disable)) {
837 		dev_warn(&sr->pdev->dev, "%s: smartreflex class driver not"
838 			"registered\n", __func__);
839 		return;
840 	}
841 
842 	sr_class->disable(voltdm, 1);
843 }
844 
845 /**
846  * omap_sr_register_pmic() - API to register pmic specific info.
847  * @pmic_data:	The structure containing pmic specific data.
848  *
849  * This API is to be called from the PMIC specific code to register with
850  * smartreflex driver pmic specific info. Currently the only info required
851  * is the smartreflex init on the PMIC side.
852  */
omap_sr_register_pmic(struct omap_sr_pmic_data * pmic_data)853 void omap_sr_register_pmic(struct omap_sr_pmic_data *pmic_data)
854 {
855 	if (!pmic_data) {
856 		pr_warning("%s: Trying to register NULL PMIC data structure"
857 			"with smartreflex\n", __func__);
858 		return;
859 	}
860 
861 	sr_pmic_data = pmic_data;
862 }
863 
864 /* PM Debug FS entries to enable and disable smartreflex. */
omap_sr_autocomp_show(void * data,u64 * val)865 static int omap_sr_autocomp_show(void *data, u64 *val)
866 {
867 	struct omap_sr *sr_info = data;
868 
869 	if (!sr_info) {
870 		pr_warning("%s: omap_sr struct not found\n", __func__);
871 		return -EINVAL;
872 	}
873 
874 	*val = sr_info->autocomp_active;
875 
876 	return 0;
877 }
878 
omap_sr_autocomp_store(void * data,u64 val)879 static int omap_sr_autocomp_store(void *data, u64 val)
880 {
881 	struct omap_sr *sr_info = data;
882 
883 	if (!sr_info) {
884 		pr_warning("%s: omap_sr struct not found\n", __func__);
885 		return -EINVAL;
886 	}
887 
888 	/* Sanity check */
889 	if (val > 1) {
890 		pr_warning("%s: Invalid argument %lld\n", __func__, val);
891 		return -EINVAL;
892 	}
893 
894 	/* control enable/disable only if there is a delta in value */
895 	if (sr_info->autocomp_active != val) {
896 		if (!val)
897 			sr_stop_vddautocomp(sr_info);
898 		else
899 			sr_start_vddautocomp(sr_info);
900 	}
901 
902 	return 0;
903 }
904 
905 DEFINE_SIMPLE_ATTRIBUTE(pm_sr_fops, omap_sr_autocomp_show,
906 			omap_sr_autocomp_store, "%llu\n");
907 
omap_sr_probe(struct platform_device * pdev)908 static int __init omap_sr_probe(struct platform_device *pdev)
909 {
910 	struct omap_sr *sr_info;
911 	struct omap_sr_data *pdata = pdev->dev.platform_data;
912 	struct resource *mem, *irq;
913 	struct dentry *nvalue_dir;
914 	struct omap_volt_data *volt_data;
915 	int i, ret = 0;
916 	char *name;
917 
918 	sr_info = kzalloc(sizeof(struct omap_sr), GFP_KERNEL);
919 	if (!sr_info) {
920 		dev_err(&pdev->dev, "%s: unable to allocate sr_info\n",
921 			__func__);
922 		return -ENOMEM;
923 	}
924 
925 	platform_set_drvdata(pdev, sr_info);
926 
927 	if (!pdata) {
928 		dev_err(&pdev->dev, "%s: platform data missing\n", __func__);
929 		ret = -EINVAL;
930 		goto err_free_devinfo;
931 	}
932 
933 	mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
934 	if (!mem) {
935 		dev_err(&pdev->dev, "%s: no mem resource\n", __func__);
936 		ret = -ENODEV;
937 		goto err_free_devinfo;
938 	}
939 
940 	mem = request_mem_region(mem->start, resource_size(mem),
941 					dev_name(&pdev->dev));
942 	if (!mem) {
943 		dev_err(&pdev->dev, "%s: no mem region\n", __func__);
944 		ret = -EBUSY;
945 		goto err_free_devinfo;
946 	}
947 
948 	irq = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
949 
950 	pm_runtime_enable(&pdev->dev);
951 	pm_runtime_irq_safe(&pdev->dev);
952 
953 	sr_info->pdev = pdev;
954 	sr_info->srid = pdev->id;
955 	sr_info->voltdm = pdata->voltdm;
956 	sr_info->nvalue_table = pdata->nvalue_table;
957 	sr_info->nvalue_count = pdata->nvalue_count;
958 	sr_info->senn_mod = pdata->senn_mod;
959 	sr_info->senp_mod = pdata->senp_mod;
960 	sr_info->autocomp_active = false;
961 	sr_info->ip_type = pdata->ip_type;
962 	sr_info->base = ioremap(mem->start, resource_size(mem));
963 	if (!sr_info->base) {
964 		dev_err(&pdev->dev, "%s: ioremap fail\n", __func__);
965 		ret = -ENOMEM;
966 		goto err_release_region;
967 	}
968 
969 	if (irq)
970 		sr_info->irq = irq->start;
971 
972 	sr_set_clk_length(sr_info);
973 	sr_set_regfields(sr_info);
974 
975 	list_add(&sr_info->node, &sr_list);
976 
977 	/*
978 	 * Call into late init to do intializations that require
979 	 * both sr driver and sr class driver to be initiallized.
980 	 */
981 	if (sr_class) {
982 		ret = sr_late_init(sr_info);
983 		if (ret) {
984 			pr_warning("%s: Error in SR late init\n", __func__);
985 			goto err_iounmap;
986 		}
987 	}
988 
989 	dev_info(&pdev->dev, "%s: SmartReflex driver initialized\n", __func__);
990 	if (!sr_dbg_dir) {
991 		sr_dbg_dir = debugfs_create_dir("smartreflex", NULL);
992 		if (IS_ERR_OR_NULL(sr_dbg_dir)) {
993 			ret = PTR_ERR(sr_dbg_dir);
994 			pr_err("%s:sr debugfs dir creation failed(%d)\n",
995 				__func__, ret);
996 			goto err_iounmap;
997 		}
998 	}
999 
1000 	name = kasprintf(GFP_KERNEL, "sr_%s", sr_info->voltdm->name);
1001 	if (!name) {
1002 		dev_err(&pdev->dev, "%s: Unable to alloc debugfs name\n",
1003 			__func__);
1004 		ret = -ENOMEM;
1005 		goto err_iounmap;
1006 	}
1007 	sr_info->dbg_dir = debugfs_create_dir(name, sr_dbg_dir);
1008 	kfree(name);
1009 	if (IS_ERR_OR_NULL(sr_info->dbg_dir)) {
1010 		dev_err(&pdev->dev, "%s: Unable to create debugfs directory\n",
1011 			__func__);
1012 		ret = PTR_ERR(sr_info->dbg_dir);
1013 		goto err_iounmap;
1014 	}
1015 
1016 	(void) debugfs_create_file("autocomp", S_IRUGO | S_IWUSR,
1017 			sr_info->dbg_dir, (void *)sr_info, &pm_sr_fops);
1018 	(void) debugfs_create_x32("errweight", S_IRUGO, sr_info->dbg_dir,
1019 			&sr_info->err_weight);
1020 	(void) debugfs_create_x32("errmaxlimit", S_IRUGO, sr_info->dbg_dir,
1021 			&sr_info->err_maxlimit);
1022 	(void) debugfs_create_x32("errminlimit", S_IRUGO, sr_info->dbg_dir,
1023 			&sr_info->err_minlimit);
1024 
1025 	nvalue_dir = debugfs_create_dir("nvalue", sr_info->dbg_dir);
1026 	if (IS_ERR_OR_NULL(nvalue_dir)) {
1027 		dev_err(&pdev->dev, "%s: Unable to create debugfs directory"
1028 			"for n-values\n", __func__);
1029 		ret = PTR_ERR(nvalue_dir);
1030 		goto err_debugfs;
1031 	}
1032 
1033 	omap_voltage_get_volttable(sr_info->voltdm, &volt_data);
1034 	if (!volt_data) {
1035 		dev_warn(&pdev->dev, "%s: No Voltage table for the"
1036 			" corresponding vdd vdd_%s. Cannot create debugfs"
1037 			"entries for n-values\n",
1038 			__func__, sr_info->voltdm->name);
1039 		ret = -ENODATA;
1040 		goto err_debugfs;
1041 	}
1042 
1043 	for (i = 0; i < sr_info->nvalue_count; i++) {
1044 		char name[NVALUE_NAME_LEN + 1];
1045 
1046 		snprintf(name, sizeof(name), "volt_%d",
1047 			 volt_data[i].volt_nominal);
1048 		(void) debugfs_create_x32(name, S_IRUGO | S_IWUSR, nvalue_dir,
1049 				&(sr_info->nvalue_table[i].nvalue));
1050 	}
1051 
1052 	return ret;
1053 
1054 err_debugfs:
1055 	debugfs_remove_recursive(sr_info->dbg_dir);
1056 err_iounmap:
1057 	list_del(&sr_info->node);
1058 	iounmap(sr_info->base);
1059 err_release_region:
1060 	release_mem_region(mem->start, resource_size(mem));
1061 err_free_devinfo:
1062 	kfree(sr_info);
1063 
1064 	return ret;
1065 }
1066 
omap_sr_remove(struct platform_device * pdev)1067 static int __devexit omap_sr_remove(struct platform_device *pdev)
1068 {
1069 	struct omap_sr_data *pdata = pdev->dev.platform_data;
1070 	struct omap_sr *sr_info;
1071 	struct resource *mem;
1072 
1073 	if (!pdata) {
1074 		dev_err(&pdev->dev, "%s: platform data missing\n", __func__);
1075 		return -EINVAL;
1076 	}
1077 
1078 	sr_info = _sr_lookup(pdata->voltdm);
1079 	if (IS_ERR(sr_info)) {
1080 		dev_warn(&pdev->dev, "%s: omap_sr struct not found\n",
1081 			__func__);
1082 		return PTR_ERR(sr_info);
1083 	}
1084 
1085 	if (sr_info->autocomp_active)
1086 		sr_stop_vddautocomp(sr_info);
1087 	if (sr_info->dbg_dir)
1088 		debugfs_remove_recursive(sr_info->dbg_dir);
1089 
1090 	list_del(&sr_info->node);
1091 	iounmap(sr_info->base);
1092 	kfree(sr_info);
1093 	mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1094 	release_mem_region(mem->start, resource_size(mem));
1095 
1096 	return 0;
1097 }
1098 
omap_sr_shutdown(struct platform_device * pdev)1099 static void __devexit omap_sr_shutdown(struct platform_device *pdev)
1100 {
1101 	struct omap_sr_data *pdata = pdev->dev.platform_data;
1102 	struct omap_sr *sr_info;
1103 
1104 	if (!pdata) {
1105 		dev_err(&pdev->dev, "%s: platform data missing\n", __func__);
1106 		return;
1107 	}
1108 
1109 	sr_info = _sr_lookup(pdata->voltdm);
1110 	if (IS_ERR(sr_info)) {
1111 		dev_warn(&pdev->dev, "%s: omap_sr struct not found\n",
1112 			__func__);
1113 		return;
1114 	}
1115 
1116 	if (sr_info->autocomp_active)
1117 		sr_stop_vddautocomp(sr_info);
1118 
1119 	return;
1120 }
1121 
1122 static struct platform_driver smartreflex_driver = {
1123 	.remove         = __devexit_p(omap_sr_remove),
1124 	.shutdown	= __devexit_p(omap_sr_shutdown),
1125 	.driver		= {
1126 		.name	= "smartreflex",
1127 	},
1128 };
1129 
sr_init(void)1130 static int __init sr_init(void)
1131 {
1132 	int ret = 0;
1133 
1134 	/*
1135 	 * sr_init is a late init. If by then a pmic specific API is not
1136 	 * registered either there is no need for anything to be done on
1137 	 * the PMIC side or somebody has forgotten to register a PMIC
1138 	 * handler. Warn for the second condition.
1139 	 */
1140 	if (sr_pmic_data && sr_pmic_data->sr_pmic_init)
1141 		sr_pmic_data->sr_pmic_init();
1142 	else
1143 		pr_warning("%s: No PMIC hook to init smartreflex\n", __func__);
1144 
1145 	ret = platform_driver_probe(&smartreflex_driver, omap_sr_probe);
1146 	if (ret) {
1147 		pr_err("%s: platform driver register failed for SR\n",
1148 			__func__);
1149 		return ret;
1150 	}
1151 
1152 	return 0;
1153 }
1154 late_initcall(sr_init);
1155 
sr_exit(void)1156 static void __exit sr_exit(void)
1157 {
1158 	platform_driver_unregister(&smartreflex_driver);
1159 }
1160 module_exit(sr_exit);
1161 
1162 MODULE_DESCRIPTION("OMAP Smartreflex Driver");
1163 MODULE_LICENSE("GPL");
1164 MODULE_ALIAS("platform:" DRIVER_NAME);
1165 MODULE_AUTHOR("Texas Instruments Inc");
1166