xref: /linux/arch/arm/mach-omap2/powerdomain.c (revision 3932b9ca55b0be314a36d3e84faff3e823c081f5)
1 /*
2  * OMAP powerdomain control
3  *
4  * Copyright (C) 2007-2008, 2011 Texas Instruments, Inc.
5  * Copyright (C) 2007-2011 Nokia Corporation
6  *
7  * Written by Paul Walmsley
8  * Added OMAP4 specific support by Abhijit Pagare <abhijitpagare@ti.com>
9  * State counting code by Tero Kristo <tero.kristo@nokia.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 #undef DEBUG
16 
17 #include <linux/kernel.h>
18 #include <linux/types.h>
19 #include <linux/list.h>
20 #include <linux/errno.h>
21 #include <linux/string.h>
22 #include <linux/spinlock.h>
23 #include <trace/events/power.h>
24 
25 #include "cm2xxx_3xxx.h"
26 #include "prcm44xx.h"
27 #include "cm44xx.h"
28 #include "prm2xxx_3xxx.h"
29 #include "prm44xx.h"
30 
31 #include <asm/cpu.h>
32 
33 #include "powerdomain.h"
34 #include "clockdomain.h"
35 #include "voltage.h"
36 
37 #include "soc.h"
38 #include "pm.h"
39 
40 #define PWRDM_TRACE_STATES_FLAG	(1<<31)
41 
42 enum {
43 	PWRDM_STATE_NOW = 0,
44 	PWRDM_STATE_PREV,
45 };
46 
47 /*
48  * Types of sleep_switch used internally in omap_set_pwrdm_state()
49  * and its associated static functions
50  *
51  * XXX Better documentation is needed here
52  */
53 #define ALREADYACTIVE_SWITCH		0
54 #define FORCEWAKEUP_SWITCH		1
55 #define LOWPOWERSTATE_SWITCH		2
56 
57 /* pwrdm_list contains all registered struct powerdomains */
58 static LIST_HEAD(pwrdm_list);
59 
60 static struct pwrdm_ops *arch_pwrdm;
61 
62 /* Private functions */
63 
64 static struct powerdomain *_pwrdm_lookup(const char *name)
65 {
66 	struct powerdomain *pwrdm, *temp_pwrdm;
67 
68 	pwrdm = NULL;
69 
70 	list_for_each_entry(temp_pwrdm, &pwrdm_list, node) {
71 		if (!strcmp(name, temp_pwrdm->name)) {
72 			pwrdm = temp_pwrdm;
73 			break;
74 		}
75 	}
76 
77 	return pwrdm;
78 }
79 
80 /**
81  * _pwrdm_register - register a powerdomain
82  * @pwrdm: struct powerdomain * to register
83  *
84  * Adds a powerdomain to the internal powerdomain list.  Returns
85  * -EINVAL if given a null pointer, -EEXIST if a powerdomain is
86  * already registered by the provided name, or 0 upon success.
87  */
88 static int _pwrdm_register(struct powerdomain *pwrdm)
89 {
90 	int i;
91 	struct voltagedomain *voltdm;
92 
93 	if (!pwrdm || !pwrdm->name)
94 		return -EINVAL;
95 
96 	if (cpu_is_omap44xx() &&
97 	    pwrdm->prcm_partition == OMAP4430_INVALID_PRCM_PARTITION) {
98 		pr_err("powerdomain: %s: missing OMAP4 PRCM partition ID\n",
99 		       pwrdm->name);
100 		return -EINVAL;
101 	}
102 
103 	if (_pwrdm_lookup(pwrdm->name))
104 		return -EEXIST;
105 
106 	if (arch_pwrdm && arch_pwrdm->pwrdm_has_voltdm)
107 		if (!arch_pwrdm->pwrdm_has_voltdm())
108 			goto skip_voltdm;
109 
110 	voltdm = voltdm_lookup(pwrdm->voltdm.name);
111 	if (!voltdm) {
112 		pr_err("powerdomain: %s: voltagedomain %s does not exist\n",
113 		       pwrdm->name, pwrdm->voltdm.name);
114 		return -EINVAL;
115 	}
116 	pwrdm->voltdm.ptr = voltdm;
117 	INIT_LIST_HEAD(&pwrdm->voltdm_node);
118 	voltdm_add_pwrdm(voltdm, pwrdm);
119 skip_voltdm:
120 	spin_lock_init(&pwrdm->_lock);
121 
122 	list_add(&pwrdm->node, &pwrdm_list);
123 
124 	/* Initialize the powerdomain's state counter */
125 	for (i = 0; i < PWRDM_MAX_PWRSTS; i++)
126 		pwrdm->state_counter[i] = 0;
127 
128 	pwrdm->ret_logic_off_counter = 0;
129 	for (i = 0; i < pwrdm->banks; i++)
130 		pwrdm->ret_mem_off_counter[i] = 0;
131 
132 	if (arch_pwrdm && arch_pwrdm->pwrdm_wait_transition)
133 		arch_pwrdm->pwrdm_wait_transition(pwrdm);
134 	pwrdm->state = pwrdm_read_pwrst(pwrdm);
135 	pwrdm->state_counter[pwrdm->state] = 1;
136 
137 	pr_debug("powerdomain: registered %s\n", pwrdm->name);
138 
139 	return 0;
140 }
141 
142 static void _update_logic_membank_counters(struct powerdomain *pwrdm)
143 {
144 	int i;
145 	u8 prev_logic_pwrst, prev_mem_pwrst;
146 
147 	prev_logic_pwrst = pwrdm_read_prev_logic_pwrst(pwrdm);
148 	if ((pwrdm->pwrsts_logic_ret == PWRSTS_OFF_RET) &&
149 	    (prev_logic_pwrst == PWRDM_POWER_OFF))
150 		pwrdm->ret_logic_off_counter++;
151 
152 	for (i = 0; i < pwrdm->banks; i++) {
153 		prev_mem_pwrst = pwrdm_read_prev_mem_pwrst(pwrdm, i);
154 
155 		if ((pwrdm->pwrsts_mem_ret[i] == PWRSTS_OFF_RET) &&
156 		    (prev_mem_pwrst == PWRDM_POWER_OFF))
157 			pwrdm->ret_mem_off_counter[i]++;
158 	}
159 }
160 
161 static int _pwrdm_state_switch(struct powerdomain *pwrdm, int flag)
162 {
163 
164 	int prev, next, state, trace_state = 0;
165 
166 	if (pwrdm == NULL)
167 		return -EINVAL;
168 
169 	state = pwrdm_read_pwrst(pwrdm);
170 
171 	switch (flag) {
172 	case PWRDM_STATE_NOW:
173 		prev = pwrdm->state;
174 		break;
175 	case PWRDM_STATE_PREV:
176 		prev = pwrdm_read_prev_pwrst(pwrdm);
177 		if (pwrdm->state != prev)
178 			pwrdm->state_counter[prev]++;
179 		if (prev == PWRDM_POWER_RET)
180 			_update_logic_membank_counters(pwrdm);
181 		/*
182 		 * If the power domain did not hit the desired state,
183 		 * generate a trace event with both the desired and hit states
184 		 */
185 		next = pwrdm_read_next_pwrst(pwrdm);
186 		if (next != prev) {
187 			trace_state = (PWRDM_TRACE_STATES_FLAG |
188 				       ((next & OMAP_POWERSTATE_MASK) << 8) |
189 				       ((prev & OMAP_POWERSTATE_MASK) << 0));
190 			trace_power_domain_target(pwrdm->name, trace_state,
191 						  smp_processor_id());
192 		}
193 		break;
194 	default:
195 		return -EINVAL;
196 	}
197 
198 	if (state != prev)
199 		pwrdm->state_counter[state]++;
200 
201 	pm_dbg_update_time(pwrdm, prev);
202 
203 	pwrdm->state = state;
204 
205 	return 0;
206 }
207 
208 static int _pwrdm_pre_transition_cb(struct powerdomain *pwrdm, void *unused)
209 {
210 	pwrdm_clear_all_prev_pwrst(pwrdm);
211 	_pwrdm_state_switch(pwrdm, PWRDM_STATE_NOW);
212 	return 0;
213 }
214 
215 static int _pwrdm_post_transition_cb(struct powerdomain *pwrdm, void *unused)
216 {
217 	_pwrdm_state_switch(pwrdm, PWRDM_STATE_PREV);
218 	return 0;
219 }
220 
221 /**
222  * _pwrdm_save_clkdm_state_and_activate - prepare for power state change
223  * @pwrdm: struct powerdomain * to operate on
224  * @curr_pwrst: current power state of @pwrdm
225  * @pwrst: power state to switch to
226  * @hwsup: ptr to a bool to return whether the clkdm is hardware-supervised
227  *
228  * Determine whether the powerdomain needs to be turned on before
229  * attempting to switch power states.  Called by
230  * omap_set_pwrdm_state().  NOTE that if the powerdomain contains
231  * multiple clockdomains, this code assumes that the first clockdomain
232  * supports software-supervised wakeup mode - potentially a problem.
233  * Returns the power state switch mode currently in use (see the
234  * "Types of sleep_switch" comment above).
235  */
236 static u8 _pwrdm_save_clkdm_state_and_activate(struct powerdomain *pwrdm,
237 					       u8 curr_pwrst, u8 pwrst,
238 					       bool *hwsup)
239 {
240 	u8 sleep_switch;
241 
242 	if (curr_pwrst < PWRDM_POWER_ON) {
243 		if (curr_pwrst > pwrst &&
244 		    pwrdm->flags & PWRDM_HAS_LOWPOWERSTATECHANGE &&
245 		    arch_pwrdm->pwrdm_set_lowpwrstchange) {
246 			sleep_switch = LOWPOWERSTATE_SWITCH;
247 		} else {
248 			*hwsup = clkdm_in_hwsup(pwrdm->pwrdm_clkdms[0]);
249 			clkdm_wakeup_nolock(pwrdm->pwrdm_clkdms[0]);
250 			sleep_switch = FORCEWAKEUP_SWITCH;
251 		}
252 	} else {
253 		sleep_switch = ALREADYACTIVE_SWITCH;
254 	}
255 
256 	return sleep_switch;
257 }
258 
259 /**
260  * _pwrdm_restore_clkdm_state - restore the clkdm hwsup state after pwrst change
261  * @pwrdm: struct powerdomain * to operate on
262  * @sleep_switch: return value from _pwrdm_save_clkdm_state_and_activate()
263  * @hwsup: should @pwrdm's first clockdomain be set to hardware-supervised mode?
264  *
265  * Restore the clockdomain state perturbed by
266  * _pwrdm_save_clkdm_state_and_activate(), and call the power state
267  * bookkeeping code.  Called by omap_set_pwrdm_state().  NOTE that if
268  * the powerdomain contains multiple clockdomains, this assumes that
269  * the first associated clockdomain supports either
270  * hardware-supervised idle control in the register, or
271  * software-supervised sleep.  No return value.
272  */
273 static void _pwrdm_restore_clkdm_state(struct powerdomain *pwrdm,
274 				       u8 sleep_switch, bool hwsup)
275 {
276 	switch (sleep_switch) {
277 	case FORCEWAKEUP_SWITCH:
278 		if (hwsup)
279 			clkdm_allow_idle_nolock(pwrdm->pwrdm_clkdms[0]);
280 		else
281 			clkdm_sleep_nolock(pwrdm->pwrdm_clkdms[0]);
282 		break;
283 	case LOWPOWERSTATE_SWITCH:
284 		if (pwrdm->flags & PWRDM_HAS_LOWPOWERSTATECHANGE &&
285 		    arch_pwrdm->pwrdm_set_lowpwrstchange)
286 			arch_pwrdm->pwrdm_set_lowpwrstchange(pwrdm);
287 		pwrdm_state_switch_nolock(pwrdm);
288 		break;
289 	}
290 }
291 
292 /* Public functions */
293 
294 /**
295  * pwrdm_register_platform_funcs - register powerdomain implementation fns
296  * @po: func pointers for arch specific implementations
297  *
298  * Register the list of function pointers used to implement the
299  * powerdomain functions on different OMAP SoCs.  Should be called
300  * before any other pwrdm_register*() function.  Returns -EINVAL if
301  * @po is null, -EEXIST if platform functions have already been
302  * registered, or 0 upon success.
303  */
304 int pwrdm_register_platform_funcs(struct pwrdm_ops *po)
305 {
306 	if (!po)
307 		return -EINVAL;
308 
309 	if (arch_pwrdm)
310 		return -EEXIST;
311 
312 	arch_pwrdm = po;
313 
314 	return 0;
315 }
316 
317 /**
318  * pwrdm_register_pwrdms - register SoC powerdomains
319  * @ps: pointer to an array of struct powerdomain to register
320  *
321  * Register the powerdomains available on a particular OMAP SoC.  Must
322  * be called after pwrdm_register_platform_funcs().  May be called
323  * multiple times.  Returns -EACCES if called before
324  * pwrdm_register_platform_funcs(); -EINVAL if the argument @ps is
325  * null; or 0 upon success.
326  */
327 int pwrdm_register_pwrdms(struct powerdomain **ps)
328 {
329 	struct powerdomain **p = NULL;
330 
331 	if (!arch_pwrdm)
332 		return -EEXIST;
333 
334 	if (!ps)
335 		return -EINVAL;
336 
337 	for (p = ps; *p; p++)
338 		_pwrdm_register(*p);
339 
340 	return 0;
341 }
342 
343 /**
344  * pwrdm_complete_init - set up the powerdomain layer
345  *
346  * Do whatever is necessary to initialize registered powerdomains and
347  * powerdomain code.  Currently, this programs the next power state
348  * for each powerdomain to ON.  This prevents powerdomains from
349  * unexpectedly losing context or entering high wakeup latency modes
350  * with non-power-management-enabled kernels.  Must be called after
351  * pwrdm_register_pwrdms().  Returns -EACCES if called before
352  * pwrdm_register_pwrdms(), or 0 upon success.
353  */
354 int pwrdm_complete_init(void)
355 {
356 	struct powerdomain *temp_p;
357 
358 	if (list_empty(&pwrdm_list))
359 		return -EACCES;
360 
361 	list_for_each_entry(temp_p, &pwrdm_list, node)
362 		pwrdm_set_next_pwrst(temp_p, PWRDM_POWER_ON);
363 
364 	return 0;
365 }
366 
367 /**
368  * pwrdm_lock - acquire a Linux spinlock on a powerdomain
369  * @pwrdm: struct powerdomain * to lock
370  *
371  * Acquire the powerdomain spinlock on @pwrdm.  No return value.
372  */
373 void pwrdm_lock(struct powerdomain *pwrdm)
374 	__acquires(&pwrdm->_lock)
375 {
376 	spin_lock_irqsave(&pwrdm->_lock, pwrdm->_lock_flags);
377 }
378 
379 /**
380  * pwrdm_unlock - release a Linux spinlock on a powerdomain
381  * @pwrdm: struct powerdomain * to unlock
382  *
383  * Release the powerdomain spinlock on @pwrdm.  No return value.
384  */
385 void pwrdm_unlock(struct powerdomain *pwrdm)
386 	__releases(&pwrdm->_lock)
387 {
388 	spin_unlock_irqrestore(&pwrdm->_lock, pwrdm->_lock_flags);
389 }
390 
391 /**
392  * pwrdm_lookup - look up a powerdomain by name, return a pointer
393  * @name: name of powerdomain
394  *
395  * Find a registered powerdomain by its name @name.  Returns a pointer
396  * to the struct powerdomain if found, or NULL otherwise.
397  */
398 struct powerdomain *pwrdm_lookup(const char *name)
399 {
400 	struct powerdomain *pwrdm;
401 
402 	if (!name)
403 		return NULL;
404 
405 	pwrdm = _pwrdm_lookup(name);
406 
407 	return pwrdm;
408 }
409 
410 /**
411  * pwrdm_for_each - call function on each registered clockdomain
412  * @fn: callback function *
413  *
414  * Call the supplied function @fn for each registered powerdomain.
415  * The callback function @fn can return anything but 0 to bail out
416  * early from the iterator.  Returns the last return value of the
417  * callback function, which should be 0 for success or anything else
418  * to indicate failure; or -EINVAL if the function pointer is null.
419  */
420 int pwrdm_for_each(int (*fn)(struct powerdomain *pwrdm, void *user),
421 		   void *user)
422 {
423 	struct powerdomain *temp_pwrdm;
424 	int ret = 0;
425 
426 	if (!fn)
427 		return -EINVAL;
428 
429 	list_for_each_entry(temp_pwrdm, &pwrdm_list, node) {
430 		ret = (*fn)(temp_pwrdm, user);
431 		if (ret)
432 			break;
433 	}
434 
435 	return ret;
436 }
437 
438 /**
439  * pwrdm_add_clkdm - add a clockdomain to a powerdomain
440  * @pwrdm: struct powerdomain * to add the clockdomain to
441  * @clkdm: struct clockdomain * to associate with a powerdomain
442  *
443  * Associate the clockdomain @clkdm with a powerdomain @pwrdm.  This
444  * enables the use of pwrdm_for_each_clkdm().  Returns -EINVAL if
445  * presented with invalid pointers; -ENOMEM if memory could not be allocated;
446  * or 0 upon success.
447  */
448 int pwrdm_add_clkdm(struct powerdomain *pwrdm, struct clockdomain *clkdm)
449 {
450 	int i;
451 	int ret = -EINVAL;
452 
453 	if (!pwrdm || !clkdm)
454 		return -EINVAL;
455 
456 	pr_debug("powerdomain: %s: associating clockdomain %s\n",
457 		 pwrdm->name, clkdm->name);
458 
459 	for (i = 0; i < PWRDM_MAX_CLKDMS; i++) {
460 		if (!pwrdm->pwrdm_clkdms[i])
461 			break;
462 #ifdef DEBUG
463 		if (pwrdm->pwrdm_clkdms[i] == clkdm) {
464 			ret = -EINVAL;
465 			goto pac_exit;
466 		}
467 #endif
468 	}
469 
470 	if (i == PWRDM_MAX_CLKDMS) {
471 		pr_debug("powerdomain: %s: increase PWRDM_MAX_CLKDMS for clkdm %s\n",
472 			 pwrdm->name, clkdm->name);
473 		WARN_ON(1);
474 		ret = -ENOMEM;
475 		goto pac_exit;
476 	}
477 
478 	pwrdm->pwrdm_clkdms[i] = clkdm;
479 
480 	ret = 0;
481 
482 pac_exit:
483 	return ret;
484 }
485 
486 /**
487  * pwrdm_del_clkdm - remove a clockdomain from a powerdomain
488  * @pwrdm: struct powerdomain * to add the clockdomain to
489  * @clkdm: struct clockdomain * to associate with a powerdomain
490  *
491  * Dissociate the clockdomain @clkdm from the powerdomain
492  * @pwrdm. Returns -EINVAL if presented with invalid pointers; -ENOENT
493  * if @clkdm was not associated with the powerdomain, or 0 upon
494  * success.
495  */
496 int pwrdm_del_clkdm(struct powerdomain *pwrdm, struct clockdomain *clkdm)
497 {
498 	int ret = -EINVAL;
499 	int i;
500 
501 	if (!pwrdm || !clkdm)
502 		return -EINVAL;
503 
504 	pr_debug("powerdomain: %s: dissociating clockdomain %s\n",
505 		 pwrdm->name, clkdm->name);
506 
507 	for (i = 0; i < PWRDM_MAX_CLKDMS; i++)
508 		if (pwrdm->pwrdm_clkdms[i] == clkdm)
509 			break;
510 
511 	if (i == PWRDM_MAX_CLKDMS) {
512 		pr_debug("powerdomain: %s: clkdm %s not associated?!\n",
513 			 pwrdm->name, clkdm->name);
514 		ret = -ENOENT;
515 		goto pdc_exit;
516 	}
517 
518 	pwrdm->pwrdm_clkdms[i] = NULL;
519 
520 	ret = 0;
521 
522 pdc_exit:
523 	return ret;
524 }
525 
526 /**
527  * pwrdm_for_each_clkdm - call function on each clkdm in a pwrdm
528  * @pwrdm: struct powerdomain * to iterate over
529  * @fn: callback function *
530  *
531  * Call the supplied function @fn for each clockdomain in the powerdomain
532  * @pwrdm.  The callback function can return anything but 0 to bail
533  * out early from the iterator.  Returns -EINVAL if presented with
534  * invalid pointers; or passes along the last return value of the
535  * callback function, which should be 0 for success or anything else
536  * to indicate failure.
537  */
538 int pwrdm_for_each_clkdm(struct powerdomain *pwrdm,
539 			 int (*fn)(struct powerdomain *pwrdm,
540 				   struct clockdomain *clkdm))
541 {
542 	int ret = 0;
543 	int i;
544 
545 	if (!fn)
546 		return -EINVAL;
547 
548 	for (i = 0; i < PWRDM_MAX_CLKDMS && !ret; i++)
549 		ret = (*fn)(pwrdm, pwrdm->pwrdm_clkdms[i]);
550 
551 	return ret;
552 }
553 
554 /**
555  * pwrdm_get_voltdm - return a ptr to the voltdm that this pwrdm resides in
556  * @pwrdm: struct powerdomain *
557  *
558  * Return a pointer to the struct voltageomain that the specified powerdomain
559  * @pwrdm exists in.
560  */
561 struct voltagedomain *pwrdm_get_voltdm(struct powerdomain *pwrdm)
562 {
563 	return pwrdm->voltdm.ptr;
564 }
565 
566 /**
567  * pwrdm_get_mem_bank_count - get number of memory banks in this powerdomain
568  * @pwrdm: struct powerdomain *
569  *
570  * Return the number of controllable memory banks in powerdomain @pwrdm,
571  * starting with 1.  Returns -EINVAL if the powerdomain pointer is null.
572  */
573 int pwrdm_get_mem_bank_count(struct powerdomain *pwrdm)
574 {
575 	if (!pwrdm)
576 		return -EINVAL;
577 
578 	return pwrdm->banks;
579 }
580 
581 /**
582  * pwrdm_set_next_pwrst - set next powerdomain power state
583  * @pwrdm: struct powerdomain * to set
584  * @pwrst: one of the PWRDM_POWER_* macros
585  *
586  * Set the powerdomain @pwrdm's next power state to @pwrst.  The powerdomain
587  * may not enter this state immediately if the preconditions for this state
588  * have not been satisfied.  Returns -EINVAL if the powerdomain pointer is
589  * null or if the power state is invalid for the powerdomin, or returns 0
590  * upon success.
591  */
592 int pwrdm_set_next_pwrst(struct powerdomain *pwrdm, u8 pwrst)
593 {
594 	int ret = -EINVAL;
595 
596 	if (!pwrdm)
597 		return -EINVAL;
598 
599 	if (!(pwrdm->pwrsts & (1 << pwrst)))
600 		return -EINVAL;
601 
602 	pr_debug("powerdomain: %s: setting next powerstate to %0x\n",
603 		 pwrdm->name, pwrst);
604 
605 	if (arch_pwrdm && arch_pwrdm->pwrdm_set_next_pwrst) {
606 		/* Trace the pwrdm desired target state */
607 		trace_power_domain_target(pwrdm->name, pwrst,
608 					  smp_processor_id());
609 		/* Program the pwrdm desired target state */
610 		ret = arch_pwrdm->pwrdm_set_next_pwrst(pwrdm, pwrst);
611 	}
612 
613 	return ret;
614 }
615 
616 /**
617  * pwrdm_read_next_pwrst - get next powerdomain power state
618  * @pwrdm: struct powerdomain * to get power state
619  *
620  * Return the powerdomain @pwrdm's next power state.  Returns -EINVAL
621  * if the powerdomain pointer is null or returns the next power state
622  * upon success.
623  */
624 int pwrdm_read_next_pwrst(struct powerdomain *pwrdm)
625 {
626 	int ret = -EINVAL;
627 
628 	if (!pwrdm)
629 		return -EINVAL;
630 
631 	if (arch_pwrdm && arch_pwrdm->pwrdm_read_next_pwrst)
632 		ret = arch_pwrdm->pwrdm_read_next_pwrst(pwrdm);
633 
634 	return ret;
635 }
636 
637 /**
638  * pwrdm_read_pwrst - get current powerdomain power state
639  * @pwrdm: struct powerdomain * to get power state
640  *
641  * Return the powerdomain @pwrdm's current power state.	Returns -EINVAL
642  * if the powerdomain pointer is null or returns the current power state
643  * upon success. Note that if the power domain only supports the ON state
644  * then just return ON as the current state.
645  */
646 int pwrdm_read_pwrst(struct powerdomain *pwrdm)
647 {
648 	int ret = -EINVAL;
649 
650 	if (!pwrdm)
651 		return -EINVAL;
652 
653 	if (pwrdm->pwrsts == PWRSTS_ON)
654 		return PWRDM_POWER_ON;
655 
656 	if (arch_pwrdm && arch_pwrdm->pwrdm_read_pwrst)
657 		ret = arch_pwrdm->pwrdm_read_pwrst(pwrdm);
658 
659 	return ret;
660 }
661 
662 /**
663  * pwrdm_read_prev_pwrst - get previous powerdomain power state
664  * @pwrdm: struct powerdomain * to get previous power state
665  *
666  * Return the powerdomain @pwrdm's previous power state.  Returns -EINVAL
667  * if the powerdomain pointer is null or returns the previous power state
668  * upon success.
669  */
670 int pwrdm_read_prev_pwrst(struct powerdomain *pwrdm)
671 {
672 	int ret = -EINVAL;
673 
674 	if (!pwrdm)
675 		return -EINVAL;
676 
677 	if (arch_pwrdm && arch_pwrdm->pwrdm_read_prev_pwrst)
678 		ret = arch_pwrdm->pwrdm_read_prev_pwrst(pwrdm);
679 
680 	return ret;
681 }
682 
683 /**
684  * pwrdm_set_logic_retst - set powerdomain logic power state upon retention
685  * @pwrdm: struct powerdomain * to set
686  * @pwrst: one of the PWRDM_POWER_* macros
687  *
688  * Set the next power state @pwrst that the logic portion of the
689  * powerdomain @pwrdm will enter when the powerdomain enters retention.
690  * This will be either RETENTION or OFF, if supported.  Returns
691  * -EINVAL if the powerdomain pointer is null or the target power
692  * state is not not supported, or returns 0 upon success.
693  */
694 int pwrdm_set_logic_retst(struct powerdomain *pwrdm, u8 pwrst)
695 {
696 	int ret = -EINVAL;
697 
698 	if (!pwrdm)
699 		return -EINVAL;
700 
701 	if (!(pwrdm->pwrsts_logic_ret & (1 << pwrst)))
702 		return -EINVAL;
703 
704 	pr_debug("powerdomain: %s: setting next logic powerstate to %0x\n",
705 		 pwrdm->name, pwrst);
706 
707 	if (arch_pwrdm && arch_pwrdm->pwrdm_set_logic_retst)
708 		ret = arch_pwrdm->pwrdm_set_logic_retst(pwrdm, pwrst);
709 
710 	return ret;
711 }
712 
713 /**
714  * pwrdm_set_mem_onst - set memory power state while powerdomain ON
715  * @pwrdm: struct powerdomain * to set
716  * @bank: memory bank number to set (0-3)
717  * @pwrst: one of the PWRDM_POWER_* macros
718  *
719  * Set the next power state @pwrst that memory bank @bank of the
720  * powerdomain @pwrdm will enter when the powerdomain enters the ON
721  * state.  @bank will be a number from 0 to 3, and represents different
722  * types of memory, depending on the powerdomain.  Returns -EINVAL if
723  * the powerdomain pointer is null or the target power state is not
724  * not supported for this memory bank, -EEXIST if the target memory
725  * bank does not exist or is not controllable, or returns 0 upon
726  * success.
727  */
728 int pwrdm_set_mem_onst(struct powerdomain *pwrdm, u8 bank, u8 pwrst)
729 {
730 	int ret = -EINVAL;
731 
732 	if (!pwrdm)
733 		return -EINVAL;
734 
735 	if (pwrdm->banks < (bank + 1))
736 		return -EEXIST;
737 
738 	if (!(pwrdm->pwrsts_mem_on[bank] & (1 << pwrst)))
739 		return -EINVAL;
740 
741 	pr_debug("powerdomain: %s: setting next memory powerstate for bank %0x while pwrdm-ON to %0x\n",
742 		 pwrdm->name, bank, pwrst);
743 
744 	if (arch_pwrdm && arch_pwrdm->pwrdm_set_mem_onst)
745 		ret = arch_pwrdm->pwrdm_set_mem_onst(pwrdm, bank, pwrst);
746 
747 	return ret;
748 }
749 
750 /**
751  * pwrdm_set_mem_retst - set memory power state while powerdomain in RET
752  * @pwrdm: struct powerdomain * to set
753  * @bank: memory bank number to set (0-3)
754  * @pwrst: one of the PWRDM_POWER_* macros
755  *
756  * Set the next power state @pwrst that memory bank @bank of the
757  * powerdomain @pwrdm will enter when the powerdomain enters the
758  * RETENTION state.  Bank will be a number from 0 to 3, and represents
759  * different types of memory, depending on the powerdomain.  @pwrst
760  * will be either RETENTION or OFF, if supported.  Returns -EINVAL if
761  * the powerdomain pointer is null or the target power state is not
762  * not supported for this memory bank, -EEXIST if the target memory
763  * bank does not exist or is not controllable, or returns 0 upon
764  * success.
765  */
766 int pwrdm_set_mem_retst(struct powerdomain *pwrdm, u8 bank, u8 pwrst)
767 {
768 	int ret = -EINVAL;
769 
770 	if (!pwrdm)
771 		return -EINVAL;
772 
773 	if (pwrdm->banks < (bank + 1))
774 		return -EEXIST;
775 
776 	if (!(pwrdm->pwrsts_mem_ret[bank] & (1 << pwrst)))
777 		return -EINVAL;
778 
779 	pr_debug("powerdomain: %s: setting next memory powerstate for bank %0x while pwrdm-RET to %0x\n",
780 		 pwrdm->name, bank, pwrst);
781 
782 	if (arch_pwrdm && arch_pwrdm->pwrdm_set_mem_retst)
783 		ret = arch_pwrdm->pwrdm_set_mem_retst(pwrdm, bank, pwrst);
784 
785 	return ret;
786 }
787 
788 /**
789  * pwrdm_read_logic_pwrst - get current powerdomain logic retention power state
790  * @pwrdm: struct powerdomain * to get current logic retention power state
791  *
792  * Return the power state that the logic portion of powerdomain @pwrdm
793  * will enter when the powerdomain enters retention.  Returns -EINVAL
794  * if the powerdomain pointer is null or returns the logic retention
795  * power state upon success.
796  */
797 int pwrdm_read_logic_pwrst(struct powerdomain *pwrdm)
798 {
799 	int ret = -EINVAL;
800 
801 	if (!pwrdm)
802 		return -EINVAL;
803 
804 	if (arch_pwrdm && arch_pwrdm->pwrdm_read_logic_pwrst)
805 		ret = arch_pwrdm->pwrdm_read_logic_pwrst(pwrdm);
806 
807 	return ret;
808 }
809 
810 /**
811  * pwrdm_read_prev_logic_pwrst - get previous powerdomain logic power state
812  * @pwrdm: struct powerdomain * to get previous logic power state
813  *
814  * Return the powerdomain @pwrdm's previous logic power state.  Returns
815  * -EINVAL if the powerdomain pointer is null or returns the previous
816  * logic power state upon success.
817  */
818 int pwrdm_read_prev_logic_pwrst(struct powerdomain *pwrdm)
819 {
820 	int ret = -EINVAL;
821 
822 	if (!pwrdm)
823 		return -EINVAL;
824 
825 	if (arch_pwrdm && arch_pwrdm->pwrdm_read_prev_logic_pwrst)
826 		ret = arch_pwrdm->pwrdm_read_prev_logic_pwrst(pwrdm);
827 
828 	return ret;
829 }
830 
831 /**
832  * pwrdm_read_logic_retst - get next powerdomain logic power state
833  * @pwrdm: struct powerdomain * to get next logic power state
834  *
835  * Return the powerdomain pwrdm's logic power state.  Returns -EINVAL
836  * if the powerdomain pointer is null or returns the next logic
837  * power state upon success.
838  */
839 int pwrdm_read_logic_retst(struct powerdomain *pwrdm)
840 {
841 	int ret = -EINVAL;
842 
843 	if (!pwrdm)
844 		return -EINVAL;
845 
846 	if (arch_pwrdm && arch_pwrdm->pwrdm_read_logic_retst)
847 		ret = arch_pwrdm->pwrdm_read_logic_retst(pwrdm);
848 
849 	return ret;
850 }
851 
852 /**
853  * pwrdm_read_mem_pwrst - get current memory bank power state
854  * @pwrdm: struct powerdomain * to get current memory bank power state
855  * @bank: memory bank number (0-3)
856  *
857  * Return the powerdomain @pwrdm's current memory power state for bank
858  * @bank.  Returns -EINVAL if the powerdomain pointer is null, -EEXIST if
859  * the target memory bank does not exist or is not controllable, or
860  * returns the current memory power state upon success.
861  */
862 int pwrdm_read_mem_pwrst(struct powerdomain *pwrdm, u8 bank)
863 {
864 	int ret = -EINVAL;
865 
866 	if (!pwrdm)
867 		return ret;
868 
869 	if (pwrdm->banks < (bank + 1))
870 		return ret;
871 
872 	if (pwrdm->flags & PWRDM_HAS_MPU_QUIRK)
873 		bank = 1;
874 
875 	if (arch_pwrdm && arch_pwrdm->pwrdm_read_mem_pwrst)
876 		ret = arch_pwrdm->pwrdm_read_mem_pwrst(pwrdm, bank);
877 
878 	return ret;
879 }
880 
881 /**
882  * pwrdm_read_prev_mem_pwrst - get previous memory bank power state
883  * @pwrdm: struct powerdomain * to get previous memory bank power state
884  * @bank: memory bank number (0-3)
885  *
886  * Return the powerdomain @pwrdm's previous memory power state for
887  * bank @bank.  Returns -EINVAL if the powerdomain pointer is null,
888  * -EEXIST if the target memory bank does not exist or is not
889  * controllable, or returns the previous memory power state upon
890  * success.
891  */
892 int pwrdm_read_prev_mem_pwrst(struct powerdomain *pwrdm, u8 bank)
893 {
894 	int ret = -EINVAL;
895 
896 	if (!pwrdm)
897 		return ret;
898 
899 	if (pwrdm->banks < (bank + 1))
900 		return ret;
901 
902 	if (pwrdm->flags & PWRDM_HAS_MPU_QUIRK)
903 		bank = 1;
904 
905 	if (arch_pwrdm && arch_pwrdm->pwrdm_read_prev_mem_pwrst)
906 		ret = arch_pwrdm->pwrdm_read_prev_mem_pwrst(pwrdm, bank);
907 
908 	return ret;
909 }
910 
911 /**
912  * pwrdm_read_mem_retst - get next memory bank power state
913  * @pwrdm: struct powerdomain * to get mext memory bank power state
914  * @bank: memory bank number (0-3)
915  *
916  * Return the powerdomain pwrdm's next memory power state for bank
917  * x.  Returns -EINVAL if the powerdomain pointer is null, -EEXIST if
918  * the target memory bank does not exist or is not controllable, or
919  * returns the next memory power state upon success.
920  */
921 int pwrdm_read_mem_retst(struct powerdomain *pwrdm, u8 bank)
922 {
923 	int ret = -EINVAL;
924 
925 	if (!pwrdm)
926 		return ret;
927 
928 	if (pwrdm->banks < (bank + 1))
929 		return ret;
930 
931 	if (arch_pwrdm && arch_pwrdm->pwrdm_read_mem_retst)
932 		ret = arch_pwrdm->pwrdm_read_mem_retst(pwrdm, bank);
933 
934 	return ret;
935 }
936 
937 /**
938  * pwrdm_clear_all_prev_pwrst - clear previous powerstate register for a pwrdm
939  * @pwrdm: struct powerdomain * to clear
940  *
941  * Clear the powerdomain's previous power state register @pwrdm.
942  * Clears the entire register, including logic and memory bank
943  * previous power states.  Returns -EINVAL if the powerdomain pointer
944  * is null, or returns 0 upon success.
945  */
946 int pwrdm_clear_all_prev_pwrst(struct powerdomain *pwrdm)
947 {
948 	int ret = -EINVAL;
949 
950 	if (!pwrdm)
951 		return ret;
952 
953 	/*
954 	 * XXX should get the powerdomain's current state here;
955 	 * warn & fail if it is not ON.
956 	 */
957 
958 	pr_debug("powerdomain: %s: clearing previous power state reg\n",
959 		 pwrdm->name);
960 
961 	if (arch_pwrdm && arch_pwrdm->pwrdm_clear_all_prev_pwrst)
962 		ret = arch_pwrdm->pwrdm_clear_all_prev_pwrst(pwrdm);
963 
964 	return ret;
965 }
966 
967 /**
968  * pwrdm_enable_hdwr_sar - enable automatic hardware SAR for a pwrdm
969  * @pwrdm: struct powerdomain *
970  *
971  * Enable automatic context save-and-restore upon power state change
972  * for some devices in the powerdomain @pwrdm.  Warning: this only
973  * affects a subset of devices in a powerdomain; check the TRM
974  * closely.  Returns -EINVAL if the powerdomain pointer is null or if
975  * the powerdomain does not support automatic save-and-restore, or
976  * returns 0 upon success.
977  */
978 int pwrdm_enable_hdwr_sar(struct powerdomain *pwrdm)
979 {
980 	int ret = -EINVAL;
981 
982 	if (!pwrdm)
983 		return ret;
984 
985 	if (!(pwrdm->flags & PWRDM_HAS_HDWR_SAR))
986 		return ret;
987 
988 	pr_debug("powerdomain: %s: setting SAVEANDRESTORE bit\n", pwrdm->name);
989 
990 	if (arch_pwrdm && arch_pwrdm->pwrdm_enable_hdwr_sar)
991 		ret = arch_pwrdm->pwrdm_enable_hdwr_sar(pwrdm);
992 
993 	return ret;
994 }
995 
996 /**
997  * pwrdm_disable_hdwr_sar - disable automatic hardware SAR for a pwrdm
998  * @pwrdm: struct powerdomain *
999  *
1000  * Disable automatic context save-and-restore upon power state change
1001  * for some devices in the powerdomain @pwrdm.  Warning: this only
1002  * affects a subset of devices in a powerdomain; check the TRM
1003  * closely.  Returns -EINVAL if the powerdomain pointer is null or if
1004  * the powerdomain does not support automatic save-and-restore, or
1005  * returns 0 upon success.
1006  */
1007 int pwrdm_disable_hdwr_sar(struct powerdomain *pwrdm)
1008 {
1009 	int ret = -EINVAL;
1010 
1011 	if (!pwrdm)
1012 		return ret;
1013 
1014 	if (!(pwrdm->flags & PWRDM_HAS_HDWR_SAR))
1015 		return ret;
1016 
1017 	pr_debug("powerdomain: %s: clearing SAVEANDRESTORE bit\n", pwrdm->name);
1018 
1019 	if (arch_pwrdm && arch_pwrdm->pwrdm_disable_hdwr_sar)
1020 		ret = arch_pwrdm->pwrdm_disable_hdwr_sar(pwrdm);
1021 
1022 	return ret;
1023 }
1024 
1025 /**
1026  * pwrdm_has_hdwr_sar - test whether powerdomain supports hardware SAR
1027  * @pwrdm: struct powerdomain *
1028  *
1029  * Returns 1 if powerdomain @pwrdm supports hardware save-and-restore
1030  * for some devices, or 0 if it does not.
1031  */
1032 bool pwrdm_has_hdwr_sar(struct powerdomain *pwrdm)
1033 {
1034 	return (pwrdm && pwrdm->flags & PWRDM_HAS_HDWR_SAR) ? 1 : 0;
1035 }
1036 
1037 int pwrdm_state_switch_nolock(struct powerdomain *pwrdm)
1038 {
1039 	int ret;
1040 
1041 	if (!pwrdm || !arch_pwrdm)
1042 		return -EINVAL;
1043 
1044 	ret = arch_pwrdm->pwrdm_wait_transition(pwrdm);
1045 	if (!ret)
1046 		ret = _pwrdm_state_switch(pwrdm, PWRDM_STATE_NOW);
1047 
1048 	return ret;
1049 }
1050 
1051 int __deprecated pwrdm_state_switch(struct powerdomain *pwrdm)
1052 {
1053 	int ret;
1054 
1055 	pwrdm_lock(pwrdm);
1056 	ret = pwrdm_state_switch_nolock(pwrdm);
1057 	pwrdm_unlock(pwrdm);
1058 
1059 	return ret;
1060 }
1061 
1062 int pwrdm_pre_transition(struct powerdomain *pwrdm)
1063 {
1064 	if (pwrdm)
1065 		_pwrdm_pre_transition_cb(pwrdm, NULL);
1066 	else
1067 		pwrdm_for_each(_pwrdm_pre_transition_cb, NULL);
1068 
1069 	return 0;
1070 }
1071 
1072 int pwrdm_post_transition(struct powerdomain *pwrdm)
1073 {
1074 	if (pwrdm)
1075 		_pwrdm_post_transition_cb(pwrdm, NULL);
1076 	else
1077 		pwrdm_for_each(_pwrdm_post_transition_cb, NULL);
1078 
1079 	return 0;
1080 }
1081 
1082 /**
1083  * omap_set_pwrdm_state - change a powerdomain's current power state
1084  * @pwrdm: struct powerdomain * to change the power state of
1085  * @pwrst: power state to change to
1086  *
1087  * Change the current hardware power state of the powerdomain
1088  * represented by @pwrdm to the power state represented by @pwrst.
1089  * Returns -EINVAL if @pwrdm is null or invalid or if the
1090  * powerdomain's current power state could not be read, or returns 0
1091  * upon success or if @pwrdm does not support @pwrst or any
1092  * lower-power state.  XXX Should not return 0 if the @pwrdm does not
1093  * support @pwrst or any lower-power state: this should be an error.
1094  */
1095 int omap_set_pwrdm_state(struct powerdomain *pwrdm, u8 pwrst)
1096 {
1097 	u8 next_pwrst, sleep_switch;
1098 	int curr_pwrst;
1099 	int ret = 0;
1100 	bool hwsup = false;
1101 
1102 	if (!pwrdm || IS_ERR(pwrdm))
1103 		return -EINVAL;
1104 
1105 	while (!(pwrdm->pwrsts & (1 << pwrst))) {
1106 		if (pwrst == PWRDM_POWER_OFF)
1107 			return ret;
1108 		pwrst--;
1109 	}
1110 
1111 	pwrdm_lock(pwrdm);
1112 
1113 	curr_pwrst = pwrdm_read_pwrst(pwrdm);
1114 	if (curr_pwrst < 0) {
1115 		ret = -EINVAL;
1116 		goto osps_out;
1117 	}
1118 
1119 	next_pwrst = pwrdm_read_next_pwrst(pwrdm);
1120 	if (curr_pwrst == pwrst && next_pwrst == pwrst)
1121 		goto osps_out;
1122 
1123 	sleep_switch = _pwrdm_save_clkdm_state_and_activate(pwrdm, curr_pwrst,
1124 							    pwrst, &hwsup);
1125 
1126 	ret = pwrdm_set_next_pwrst(pwrdm, pwrst);
1127 	if (ret)
1128 		pr_err("%s: unable to set power state of powerdomain: %s\n",
1129 		       __func__, pwrdm->name);
1130 
1131 	_pwrdm_restore_clkdm_state(pwrdm, sleep_switch, hwsup);
1132 
1133 osps_out:
1134 	pwrdm_unlock(pwrdm);
1135 
1136 	return ret;
1137 }
1138 
1139 /**
1140  * pwrdm_get_context_loss_count - get powerdomain's context loss count
1141  * @pwrdm: struct powerdomain * to wait for
1142  *
1143  * Context loss count is the sum of powerdomain off-mode counter, the
1144  * logic off counter and the per-bank memory off counter.  Returns negative
1145  * (and WARNs) upon error, otherwise, returns the context loss count.
1146  */
1147 int pwrdm_get_context_loss_count(struct powerdomain *pwrdm)
1148 {
1149 	int i, count;
1150 
1151 	if (!pwrdm) {
1152 		WARN(1, "powerdomain: %s: pwrdm is null\n", __func__);
1153 		return -ENODEV;
1154 	}
1155 
1156 	count = pwrdm->state_counter[PWRDM_POWER_OFF];
1157 	count += pwrdm->ret_logic_off_counter;
1158 
1159 	for (i = 0; i < pwrdm->banks; i++)
1160 		count += pwrdm->ret_mem_off_counter[i];
1161 
1162 	/*
1163 	 * Context loss count has to be a non-negative value. Clear the sign
1164 	 * bit to get a value range from 0 to INT_MAX.
1165 	 */
1166 	count &= INT_MAX;
1167 
1168 	pr_debug("powerdomain: %s: context loss count = %d\n",
1169 		 pwrdm->name, count);
1170 
1171 	return count;
1172 }
1173 
1174 /**
1175  * pwrdm_can_ever_lose_context - can this powerdomain ever lose context?
1176  * @pwrdm: struct powerdomain *
1177  *
1178  * Given a struct powerdomain * @pwrdm, returns 1 if the powerdomain
1179  * can lose either memory or logic context or if @pwrdm is invalid, or
1180  * returns 0 otherwise.  This function is not concerned with how the
1181  * powerdomain registers are programmed (i.e., to go off or not); it's
1182  * concerned with whether it's ever possible for this powerdomain to
1183  * go off while some other part of the chip is active.  This function
1184  * assumes that every powerdomain can go to either ON or INACTIVE.
1185  */
1186 bool pwrdm_can_ever_lose_context(struct powerdomain *pwrdm)
1187 {
1188 	int i;
1189 
1190 	if (!pwrdm) {
1191 		pr_debug("powerdomain: %s: invalid powerdomain pointer\n",
1192 			 __func__);
1193 		return 1;
1194 	}
1195 
1196 	if (pwrdm->pwrsts & PWRSTS_OFF)
1197 		return 1;
1198 
1199 	if (pwrdm->pwrsts & PWRSTS_RET) {
1200 		if (pwrdm->pwrsts_logic_ret & PWRSTS_OFF)
1201 			return 1;
1202 
1203 		for (i = 0; i < pwrdm->banks; i++)
1204 			if (pwrdm->pwrsts_mem_ret[i] & PWRSTS_OFF)
1205 				return 1;
1206 	}
1207 
1208 	for (i = 0; i < pwrdm->banks; i++)
1209 		if (pwrdm->pwrsts_mem_on[i] & PWRSTS_OFF)
1210 			return 1;
1211 
1212 	return 0;
1213 }
1214