Merge branch 'restart-cleanup' into restart
[linux-2.6-block.git] / arch / arm / mach-omap2 / cpuidle34xx.c
CommitLineData
99e6a4d2
RN
1/*
2 * linux/arch/arm/mach-omap2/cpuidle34xx.c
3 *
4 * OMAP3 CPU IDLE Routines
5 *
6 * Copyright (C) 2008 Texas Instruments, Inc.
7 * Rajendra Nayak <rnayak@ti.com>
8 *
9 * Copyright (C) 2007 Texas Instruments, Inc.
10 * Karthik Dasu <karthik-dp@ti.com>
11 *
12 * Copyright (C) 2006 Nokia Corporation
13 * Tony Lindgren <tony@atomide.com>
14 *
15 * Copyright (C) 2005 Texas Instruments, Inc.
16 * Richard Woodruff <r-woodruff2@ti.com>
17 *
18 * Based on pm.c for omap2
19 *
20 * This program is free software; you can redistribute it and/or modify
21 * it under the terms of the GNU General Public License version 2 as
22 * published by the Free Software Foundation.
23 */
24
cf22854c 25#include <linux/sched.h>
99e6a4d2 26#include <linux/cpuidle.h>
5698eb4e 27#include <linux/export.h>
99e6a4d2
RN
28
29#include <plat/prcm.h>
20b01669 30#include <plat/irqs.h>
72e06d08 31#include "powerdomain.h"
1540f214 32#include "clockdomain.h"
0f724ed9 33#include <plat/serial.h>
99e6a4d2 34
c98e2230 35#include "pm.h"
4814ced5 36#include "control.h"
c98e2230 37
99e6a4d2
RN
38#ifdef CONFIG_CPU_IDLE
39
bb4de3df
KH
40/*
41 * The latencies/thresholds for various C states have
42 * to be configured from the respective board files.
43 * These are some default values (which might not provide
44 * the best power savings) used on boards which do not
45 * pass these details from the board file.
46 */
47static struct cpuidle_params cpuidle_params_table[] = {
48 /* C1 */
866ba0ef 49 {2 + 2, 5, 1},
bb4de3df 50 /* C2 */
866ba0ef 51 {10 + 10, 30, 1},
bb4de3df 52 /* C3 */
866ba0ef 53 {50 + 50, 300, 1},
bb4de3df 54 /* C4 */
866ba0ef 55 {1500 + 1800, 4000, 1},
bb4de3df 56 /* C5 */
866ba0ef 57 {2500 + 7500, 12000, 1},
bb4de3df 58 /* C6 */
866ba0ef 59 {3000 + 8500, 15000, 1},
bb4de3df 60 /* C7 */
866ba0ef 61 {10000 + 30000, 300000, 1},
bb4de3df 62};
badc303a
JP
63#define OMAP3_NUM_STATES ARRAY_SIZE(cpuidle_params_table)
64
65/* Mach specific information to be recorded in the C-state driver_data */
66struct omap3_idle_statedata {
67 u32 mpu_state;
68 u32 core_state;
69 u8 valid;
70};
71struct omap3_idle_statedata omap3_idle_data[OMAP3_NUM_STATES];
72
73struct powerdomain *mpu_pd, *core_pd, *per_pd, *cam_pd;
bb4de3df 74
06d8f065
PDS
75static int _cpuidle_allow_idle(struct powerdomain *pwrdm,
76 struct clockdomain *clkdm)
77{
5cd1937b 78 clkdm_allow_idle(clkdm);
06d8f065
PDS
79 return 0;
80}
81
82static int _cpuidle_deny_idle(struct powerdomain *pwrdm,
83 struct clockdomain *clkdm)
84{
5cd1937b 85 clkdm_deny_idle(clkdm);
06d8f065
PDS
86 return 0;
87}
88
99e6a4d2
RN
89/**
90 * omap3_enter_idle - Programs OMAP3 to enter the specified state
91 * @dev: cpuidle device
46bcfad7 92 * @drv: cpuidle driver
e978aa7d 93 * @index: the index of state to be entered
99e6a4d2
RN
94 *
95 * Called from the CPUidle framework to program the device to the
96 * specified target state selected by the governor.
97 */
98static int omap3_enter_idle(struct cpuidle_device *dev,
46bcfad7 99 struct cpuidle_driver *drv,
e978aa7d 100 int index)
99e6a4d2 101{
e978aa7d 102 struct omap3_idle_statedata *cx =
4202735e 103 cpuidle_get_statedata(&dev->states_usage[index]);
99e6a4d2 104 struct timespec ts_preidle, ts_postidle, ts_idle;
c98e2230 105 u32 mpu_state = cx->mpu_state, core_state = cx->core_state;
e978aa7d 106 int idle_time;
99e6a4d2 107
99e6a4d2
RN
108 /* Used to keep track of the total time in idle */
109 getnstimeofday(&ts_preidle);
110
111 local_irq_disable();
112 local_fiq_disable();
113
7139178e
JH
114 pwrdm_set_next_pwrst(mpu_pd, mpu_state);
115 pwrdm_set_next_pwrst(core_pd, core_state);
20b01669 116
cf22854c 117 if (omap_irq_pending() || need_resched())
20b01669 118 goto return_sleep_time;
99e6a4d2 119
badc303a 120 /* Deny idle for C1 */
e978aa7d 121 if (index == 0) {
06d8f065
PDS
122 pwrdm_for_each_clkdm(mpu_pd, _cpuidle_deny_idle);
123 pwrdm_for_each_clkdm(core_pd, _cpuidle_deny_idle);
124 }
125
99e6a4d2
RN
126 /* Execute ARM wfi */
127 omap_sram_idle();
128
badc303a 129 /* Re-allow idle for C1 */
e978aa7d 130 if (index == 0) {
06d8f065
PDS
131 pwrdm_for_each_clkdm(mpu_pd, _cpuidle_allow_idle);
132 pwrdm_for_each_clkdm(core_pd, _cpuidle_allow_idle);
133 }
134
20b01669 135return_sleep_time:
99e6a4d2
RN
136 getnstimeofday(&ts_postidle);
137 ts_idle = timespec_sub(ts_postidle, ts_preidle);
138
139 local_irq_enable();
140 local_fiq_enable();
141
e978aa7d
DD
142 idle_time = ts_idle.tv_nsec / NSEC_PER_USEC + ts_idle.tv_sec * \
143 USEC_PER_SEC;
144
145 /* Update cpuidle counters */
146 dev->last_residency = idle_time;
147
148 return index;
99e6a4d2
RN
149}
150
6af83b38 151/**
04908918 152 * next_valid_state - Find next valid C-state
6af83b38 153 * @dev: cpuidle device
46bcfad7 154 * @drv: cpuidle driver
e978aa7d 155 * @index: Index of currently selected c-state
6af83b38 156 *
e978aa7d
DD
157 * If the state corresponding to index is valid, index is returned back
158 * to the caller. Else, this function searches for a lower c-state which is
159 * still valid (as defined in omap3_power_states[]) and returns its index.
04908918
JP
160 *
161 * A state is valid if the 'valid' field is enabled and
162 * if it satisfies the enable_off_mode condition.
6af83b38 163 */
e978aa7d 164static int next_valid_state(struct cpuidle_device *dev,
46bcfad7 165 struct cpuidle_driver *drv,
e978aa7d 166 int index)
6af83b38 167{
4202735e 168 struct cpuidle_state_usage *curr_usage = &dev->states_usage[index];
46bcfad7 169 struct cpuidle_state *curr = &drv->states[index];
4202735e 170 struct omap3_idle_statedata *cx = cpuidle_get_statedata(curr_usage);
04908918
JP
171 u32 mpu_deepest_state = PWRDM_POWER_RET;
172 u32 core_deepest_state = PWRDM_POWER_RET;
e978aa7d 173 int next_index = -1;
04908918
JP
174
175 if (enable_off_mode) {
176 mpu_deepest_state = PWRDM_POWER_OFF;
177 /*
178 * Erratum i583: valable for ES rev < Es1.2 on 3630.
179 * CORE OFF mode is not supported in a stable form, restrict
180 * instead the CORE state to RET.
181 */
182 if (!IS_PM34XX_ERRATUM(PM_SDRC_WAKEUP_ERRATUM_i583))
183 core_deepest_state = PWRDM_POWER_OFF;
184 }
6af83b38
SP
185
186 /* Check if current state is valid */
04908918
JP
187 if ((cx->valid) &&
188 (cx->mpu_state >= mpu_deepest_state) &&
189 (cx->core_state >= core_deepest_state)) {
e978aa7d 190 return index;
6af83b38 191 } else {
badc303a 192 int idx = OMAP3_NUM_STATES - 1;
6af83b38 193
c6cd91de 194 /* Reach the current state starting at highest C-state */
badc303a 195 for (; idx >= 0; idx--) {
46bcfad7 196 if (&drv->states[idx] == curr) {
e978aa7d 197 next_index = idx;
6af83b38
SP
198 break;
199 }
200 }
201
c6cd91de 202 /* Should never hit this condition */
e978aa7d 203 WARN_ON(next_index == -1);
6af83b38
SP
204
205 /*
206 * Drop to next valid state.
207 * Start search from the next (lower) state.
208 */
209 idx--;
badc303a 210 for (; idx >= 0; idx--) {
4202735e 211 cx = cpuidle_get_statedata(&dev->states_usage[idx]);
04908918
JP
212 if ((cx->valid) &&
213 (cx->mpu_state >= mpu_deepest_state) &&
214 (cx->core_state >= core_deepest_state)) {
e978aa7d 215 next_index = idx;
6af83b38
SP
216 break;
217 }
218 }
219 /*
badc303a 220 * C1 is always valid.
e978aa7d
DD
221 * So, no need to check for 'next_index == -1' outside
222 * this loop.
6af83b38
SP
223 */
224 }
225
e978aa7d 226 return next_index;
6af83b38
SP
227}
228
99e6a4d2
RN
229/**
230 * omap3_enter_idle_bm - Checks for any bus activity
231 * @dev: cpuidle device
46bcfad7 232 * @drv: cpuidle driver
e978aa7d 233 * @index: array index of target state to be programmed
99e6a4d2 234 *
badc303a
JP
235 * This function checks for any pending activity and then programs
236 * the device to the specified or a safer state.
99e6a4d2
RN
237 */
238static int omap3_enter_idle_bm(struct cpuidle_device *dev,
46bcfad7 239 struct cpuidle_driver *drv,
e978aa7d 240 int index)
99e6a4d2 241{
e978aa7d 242 int new_state_idx;
c6cd91de 243 u32 core_next_state, per_next_state = 0, per_saved_state = 0, cam_state;
badc303a 244 struct omap3_idle_statedata *cx;
e7410cf7 245 int ret;
0f724ed9 246
c6cd91de 247 if (!omap3_can_sleep()) {
46bcfad7 248 new_state_idx = drv->safe_state_index;
e7410cf7
KH
249 goto select_state;
250 }
251
e7410cf7
KH
252 /*
253 * Prevent idle completely if CAM is active.
254 * CAM does not have wakeup capability in OMAP3.
255 */
256 cam_state = pwrdm_read_pwrst(cam_pd);
257 if (cam_state == PWRDM_POWER_ON) {
46bcfad7 258 new_state_idx = drv->safe_state_index;
e7410cf7
KH
259 goto select_state;
260 }
261
c6cd91de
JP
262 /*
263 * FIXME: we currently manage device-specific idle states
264 * for PER and CORE in combination with CPU-specific
265 * idle states. This is wrong, and device-specific
266 * idle management needs to be separated out into
267 * its own code.
268 */
269
e7410cf7
KH
270 /*
271 * Prevent PER off if CORE is not in retention or off as this
272 * would disable PER wakeups completely.
273 */
4202735e 274 cx = cpuidle_get_statedata(&dev->states_usage[index]);
c6cd91de 275 core_next_state = cx->core_state;
e7410cf7
KH
276 per_next_state = per_saved_state = pwrdm_read_next_pwrst(per_pd);
277 if ((per_next_state == PWRDM_POWER_OFF) &&
65707fb3 278 (core_next_state > PWRDM_POWER_RET))
e7410cf7 279 per_next_state = PWRDM_POWER_RET;
0f724ed9 280
e7410cf7
KH
281 /* Are we changing PER target state? */
282 if (per_next_state != per_saved_state)
283 pwrdm_set_next_pwrst(per_pd, per_next_state);
284
46bcfad7 285 new_state_idx = next_valid_state(dev, drv, index);
c6cd91de 286
e7410cf7 287select_state:
46bcfad7 288 ret = omap3_enter_idle(dev, drv, new_state_idx);
e7410cf7
KH
289
290 /* Restore original PER state if it was modified */
291 if (per_next_state != per_saved_state)
292 pwrdm_set_next_pwrst(per_pd, per_saved_state);
293
294 return ret;
99e6a4d2
RN
295}
296
297DEFINE_PER_CPU(struct cpuidle_device, omap3_idle_dev);
298
bb4de3df
KH
299void omap3_pm_init_cpuidle(struct cpuidle_params *cpuidle_board_params)
300{
301 int i;
302
303 if (!cpuidle_board_params)
304 return;
305
badc303a
JP
306 for (i = 0; i < OMAP3_NUM_STATES; i++) {
307 cpuidle_params_table[i].valid = cpuidle_board_params[i].valid;
866ba0ef
JP
308 cpuidle_params_table[i].exit_latency =
309 cpuidle_board_params[i].exit_latency;
310 cpuidle_params_table[i].target_residency =
311 cpuidle_board_params[i].target_residency;
bb4de3df
KH
312 }
313 return;
314}
315
99e6a4d2
RN
316struct cpuidle_driver omap3_idle_driver = {
317 .name = "omap3_idle",
318 .owner = THIS_MODULE,
319};
320
46bcfad7
DD
321/* Helper to fill the C-state common data*/
322static inline void _fill_cstate(struct cpuidle_driver *drv,
badc303a
JP
323 int idx, const char *descr)
324{
46bcfad7 325 struct cpuidle_state *state = &drv->states[idx];
badc303a
JP
326
327 state->exit_latency = cpuidle_params_table[idx].exit_latency;
328 state->target_residency = cpuidle_params_table[idx].target_residency;
329 state->flags = CPUIDLE_FLAG_TIME_VALID;
330 state->enter = omap3_enter_idle_bm;
badc303a
JP
331 sprintf(state->name, "C%d", idx + 1);
332 strncpy(state->desc, descr, CPUIDLE_DESC_LEN);
46bcfad7
DD
333
334}
335
336/* Helper to register the driver_data */
337static inline struct omap3_idle_statedata *_fill_cstate_usage(
338 struct cpuidle_device *dev,
339 int idx)
340{
341 struct omap3_idle_statedata *cx = &omap3_idle_data[idx];
342 struct cpuidle_state_usage *state_usage = &dev->states_usage[idx];
343
344 cx->valid = cpuidle_params_table[idx].valid;
4202735e 345 cpuidle_set_statedata(state_usage, cx);
badc303a
JP
346
347 return cx;
348}
349
99e6a4d2
RN
350/**
351 * omap3_idle_init - Init routine for OMAP3 idle
352 *
badc303a 353 * Registers the OMAP3 specific cpuidle driver to the cpuidle
99e6a4d2
RN
354 * framework with the valid set of states.
355 */
0343371e 356int __init omap3_idle_init(void)
99e6a4d2 357{
99e6a4d2 358 struct cpuidle_device *dev;
46bcfad7 359 struct cpuidle_driver *drv = &omap3_idle_driver;
badc303a 360 struct omap3_idle_statedata *cx;
99e6a4d2
RN
361
362 mpu_pd = pwrdm_lookup("mpu_pwrdm");
20b01669 363 core_pd = pwrdm_lookup("core_pwrdm");
e7410cf7
KH
364 per_pd = pwrdm_lookup("per_pwrdm");
365 cam_pd = pwrdm_lookup("cam_pwrdm");
99e6a4d2 366
46bcfad7
DD
367
368 drv->safe_state_index = -1;
99e6a4d2
RN
369 dev = &per_cpu(omap3_idle_dev, smp_processor_id());
370
badc303a 371 /* C1 . MPU WFI + Core active */
46bcfad7
DD
372 _fill_cstate(drv, 0, "MPU ON + CORE ON");
373 (&drv->states[0])->enter = omap3_enter_idle;
374 drv->safe_state_index = 0;
375 cx = _fill_cstate_usage(dev, 0);
badc303a
JP
376 cx->valid = 1; /* C1 is always valid */
377 cx->mpu_state = PWRDM_POWER_ON;
378 cx->core_state = PWRDM_POWER_ON;
379
380 /* C2 . MPU WFI + Core inactive */
46bcfad7
DD
381 _fill_cstate(drv, 1, "MPU ON + CORE ON");
382 cx = _fill_cstate_usage(dev, 1);
badc303a
JP
383 cx->mpu_state = PWRDM_POWER_ON;
384 cx->core_state = PWRDM_POWER_ON;
385
386 /* C3 . MPU CSWR + Core inactive */
46bcfad7
DD
387 _fill_cstate(drv, 2, "MPU RET + CORE ON");
388 cx = _fill_cstate_usage(dev, 2);
badc303a
JP
389 cx->mpu_state = PWRDM_POWER_RET;
390 cx->core_state = PWRDM_POWER_ON;
391
392 /* C4 . MPU OFF + Core inactive */
46bcfad7
DD
393 _fill_cstate(drv, 3, "MPU OFF + CORE ON");
394 cx = _fill_cstate_usage(dev, 3);
badc303a
JP
395 cx->mpu_state = PWRDM_POWER_OFF;
396 cx->core_state = PWRDM_POWER_ON;
397
398 /* C5 . MPU RET + Core RET */
46bcfad7
DD
399 _fill_cstate(drv, 4, "MPU RET + CORE RET");
400 cx = _fill_cstate_usage(dev, 4);
badc303a
JP
401 cx->mpu_state = PWRDM_POWER_RET;
402 cx->core_state = PWRDM_POWER_RET;
99e6a4d2 403
badc303a 404 /* C6 . MPU OFF + Core RET */
46bcfad7
DD
405 _fill_cstate(drv, 5, "MPU OFF + CORE RET");
406 cx = _fill_cstate_usage(dev, 5);
badc303a
JP
407 cx->mpu_state = PWRDM_POWER_OFF;
408 cx->core_state = PWRDM_POWER_RET;
409
410 /* C7 . MPU OFF + Core OFF */
46bcfad7
DD
411 _fill_cstate(drv, 6, "MPU OFF + CORE OFF");
412 cx = _fill_cstate_usage(dev, 6);
badc303a
JP
413 /*
414 * Erratum i583: implementation for ES rev < Es1.2 on 3630. We cannot
415 * enable OFF mode in a stable form for previous revisions.
416 * We disable C7 state as a result.
417 */
418 if (IS_PM34XX_ERRATUM(PM_SDRC_WAKEUP_ERRATUM_i583)) {
419 cx->valid = 0;
420 pr_warn("%s: core off state C7 disabled due to i583\n",
421 __func__);
422 }
423 cx->mpu_state = PWRDM_POWER_OFF;
424 cx->core_state = PWRDM_POWER_OFF;
99e6a4d2 425
46bcfad7
DD
426 drv->state_count = OMAP3_NUM_STATES;
427 cpuidle_register_driver(&omap3_idle_driver);
428
badc303a 429 dev->state_count = OMAP3_NUM_STATES;
99e6a4d2
RN
430 if (cpuidle_register_device(dev)) {
431 printk(KERN_ERR "%s: CPUidle register device failed\n",
432 __func__);
433 return -EIO;
434 }
435
436 return 0;
437}
0343371e
KJ
438#else
439int __init omap3_idle_init(void)
440{
441 return 0;
442}
99e6a4d2 443#endif /* CONFIG_CPU_IDLE */