1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
|
/*
* linux/arch/arm/mach-omap2/cpuidle34xx.c
*
* OMAP3 CPU IDLE Routines
*
* Copyright (C) 2008 Texas Instruments, Inc.
* Rajendra Nayak <rnayak@ti.com>
*
* Copyright (C) 2007 Texas Instruments, Inc.
* Karthik Dasu <karthik-dp@ti.com>
*
* Copyright (C) 2006 Nokia Corporation
* Tony Lindgren <tony@atomide.com>
*
* Copyright (C) 2005 Texas Instruments, Inc.
* Richard Woodruff <r-woodruff2@ti.com>
*
* Based on pm.c for omap2
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*/
#include <linux/sched.h>
#include <linux/cpuidle.h>
#include <plat/prcm.h>
#include <plat/irqs.h>
#include "powerdomain.h"
#include "clockdomain.h"
#include <plat/serial.h>
#include "pm.h"
#include "control.h"
#ifdef CONFIG_CPU_IDLE
#define OMAP3_MAX_STATES 7
#define OMAP3_STATE_C1 0 /* C1 - MPU WFI + Core active */
#define OMAP3_STATE_C2 1 /* C2 - MPU WFI + Core inactive */
#define OMAP3_STATE_C3 2 /* C3 - MPU CSWR + Core inactive */
#define OMAP3_STATE_C4 3 /* C4 - MPU OFF + Core iactive */
#define OMAP3_STATE_C5 4 /* C5 - MPU RET + Core RET */
#define OMAP3_STATE_C6 5 /* C6 - MPU OFF + Core RET */
#define OMAP3_STATE_C7 6 /* C7 - MPU OFF + Core OFF */
#define OMAP3_STATE_MAX OMAP3_STATE_C7
struct omap3_processor_cx {
u8 valid;
u8 type;
u32 sleep_latency;
u32 wakeup_latency;
u32 mpu_state;
u32 core_state;
u32 threshold;
u32 flags;
};
struct omap3_processor_cx omap3_power_states[OMAP3_MAX_STATES];
struct omap3_processor_cx current_cx_state;
struct powerdomain *mpu_pd, *core_pd, *per_pd;
struct powerdomain *cam_pd;
/*
* The latencies/thresholds for various C states have
* to be configured from the respective board files.
* These are some default values (which might not provide
* the best power savings) used on boards which do not
* pass these details from the board file.
*/
static struct cpuidle_params cpuidle_params_table[] = {
/* C1 */
{1, 2, 2, 5},
/* C2 */
{1, 10, 10, 30},
/* C3 */
{1, 50, 50, 300},
/* C4 */
{1, 1500, 1800, 4000},
/* C5 */
{1, 2500, 7500, 12000},
/* C6 */
{1, 3000, 8500, 15000},
/* C7 */
{1, 10000, 30000, 300000},
};
static int omap3_idle_bm_check(void)
{
if (!omap3_can_sleep())
return 1;
return 0;
}
static int _cpuidle_allow_idle(struct powerdomain *pwrdm,
struct clockdomain *clkdm)
{
omap2_clkdm_allow_idle(clkdm);
return 0;
}
static int _cpuidle_deny_idle(struct powerdomain *pwrdm,
struct clockdomain *clkdm)
{
omap2_clkdm_deny_idle(clkdm);
return 0;
}
/**
* omap3_enter_idle - Programs OMAP3 to enter the specified state
* @dev: cpuidle device
* @state: The target state to be programmed
*
* Called from the CPUidle framework to program the device to the
* specified target state selected by the governor.
*/
static int omap3_enter_idle(struct cpuidle_device *dev,
struct cpuidle_state *state)
{
struct omap3_processor_cx *cx = cpuidle_get_statedata(state);
struct timespec ts_preidle, ts_postidle, ts_idle;
u32 mpu_state = cx->mpu_state, core_state = cx->core_state;
current_cx_state = *cx;
/* Used to keep track of the total time in idle */
getnstimeofday(&ts_preidle);
local_irq_disable();
local_fiq_disable();
pwrdm_set_next_pwrst(mpu_pd, mpu_state);
pwrdm_set_next_pwrst(core_pd, core_state);
if (omap_irq_pending() || need_resched())
goto return_sleep_time;
if (cx->type == OMAP3_STATE_C1) {
pwrdm_for_each_clkdm(mpu_pd, _cpuidle_deny_idle);
pwrdm_for_each_clkdm(core_pd, _cpuidle_deny_idle);
}
/* Execute ARM wfi */
omap_sram_idle();
if (cx->type == OMAP3_STATE_C1) {
pwrdm_for_each_clkdm(mpu_pd, _cpuidle_allow_idle);
pwrdm_for_each_clkdm(core_pd, _cpuidle_allow_idle);
}
return_sleep_time:
getnstimeofday(&ts_postidle);
ts_idle = timespec_sub(ts_postidle, ts_preidle);
local_irq_enable();
local_fiq_enable();
return ts_idle.tv_nsec / NSEC_PER_USEC + ts_idle.tv_sec * USEC_PER_SEC;
}
/**
* next_valid_state - Find next valid c-state
* @dev: cpuidle device
* @state: Currently selected c-state
*
* If the current state is valid, it is returned back to the caller.
* Else, this function searches for a lower c-state which is still
* valid (as defined in omap3_power_states[]).
*/
static struct cpuidle_state *next_valid_state(struct cpuidle_device *dev,
struct cpuidle_state *curr)
{
struct cpuidle_state *next = NULL;
struct omap3_processor_cx *cx;
cx = (struct omap3_processor_cx *)cpuidle_get_statedata(curr);
/* Check if current state is valid */
if (cx->valid) {
return curr;
} else {
u8 idx = OMAP3_STATE_MAX;
/*
* Reach the current state starting at highest C-state
*/
for (; idx >= OMAP3_STATE_C1; idx--) {
if (&dev->states[idx] == curr) {
next = &dev->states[idx];
break;
}
}
/*
* Should never hit this condition.
*/
WARN_ON(next == NULL);
/*
* Drop to next valid state.
* Start search from the next (lower) state.
*/
idx--;
for (; idx >= OMAP3_STATE_C1; idx--) {
struct omap3_processor_cx *cx;
cx = cpuidle_get_statedata(&dev->states[idx]);
if (cx->valid) {
next = &dev->states[idx];
break;
}
}
/*
* C1 and C2 are always valid.
* So, no need to check for 'next==NULL' outside this loop.
*/
}
return next;
}
/**
* omap3_enter_idle_bm - Checks for any bus activity
* @dev: cpuidle device
* @state: The target state to be programmed
*
* Used for C states with CPUIDLE_FLAG_CHECK_BM flag set. This
* function checks for any pending activity and then programs the
* device to the specified or a safer state.
*/
static int omap3_enter_idle_bm(struct cpuidle_device *dev,
struct cpuidle_state *state)
{
struct cpuidle_state *new_state = next_valid_state(dev, state);
u32 core_next_state, per_next_state = 0, per_saved_state = 0;
u32 cam_state;
struct omap3_processor_cx *cx;
int ret;
if ((state->flags & CPUIDLE_FLAG_CHECK_BM) && omap3_idle_bm_check()) {
BUG_ON(!dev->safe_state);
new_state = dev->safe_state;
goto select_state;
}
cx = cpuidle_get_statedata(state);
core_next_state = cx->core_state;
/*
* FIXME: we currently manage device-specific idle states
* for PER and CORE in combination with CPU-specific
* idle states. This is wrong, and device-specific
* idle managment needs to be separated out into
* its own code.
*/
/*
* Prevent idle completely if CAM is active.
* CAM does not have wakeup capability in OMAP3.
*/
cam_state = pwrdm_read_pwrst(cam_pd);
if (cam_state == PWRDM_POWER_ON) {
new_state = dev->safe_state;
goto select_state;
}
/*
* Prevent PER off if CORE is not in retention or off as this
* would disable PER wakeups completely.
*/
per_next_state = per_saved_state = pwrdm_read_next_pwrst(per_pd);
if ((per_next_state == PWRDM_POWER_OFF) &&
(core_next_state > PWRDM_POWER_RET))
per_next_state = PWRDM_POWER_RET;
/* Are we changing PER target state? */
if (per_next_state != per_saved_state)
pwrdm_set_next_pwrst(per_pd, per_next_state);
select_state:
dev->last_state = new_state;
ret = omap3_enter_idle(dev, new_state);
/* Restore original PER state if it was modified */
if (per_next_state != per_saved_state)
pwrdm_set_next_pwrst(per_pd, per_saved_state);
return ret;
}
DEFINE_PER_CPU(struct cpuidle_device, omap3_idle_dev);
/**
* omap3_cpuidle_update_states() - Update the cpuidle states
* @mpu_deepest_state: Enable states upto and including this for mpu domain
* @core_deepest_state: Enable states upto and including this for core domain
*
* This goes through the list of states available and enables and disables the
* validity of C states based on deepest state that can be achieved for the
* variable domain
*/
void omap3_cpuidle_update_states(u32 mpu_deepest_state, u32 core_deepest_state)
{
int i;
for (i = OMAP3_STATE_C1; i < OMAP3_MAX_STATES; i++) {
struct omap3_processor_cx *cx = &omap3_power_states[i];
if ((cx->mpu_state >= mpu_deepest_state) &&
(cx->core_state >= core_deepest_state)) {
cx->valid = 1;
} else
|