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 
25 #include <linux/sched.h>
26 #include <linux/cpuidle.h>
27 
28 #include <plat/prcm.h>
29 #include <plat/irqs.h>
30 #include <plat/powerdomain.h>
31 #include <plat/clockdomain.h>
32 #include <plat/control.h>
33 #include <plat/serial.h>
34 
35 #include "pm.h"
36 
37 #ifdef CONFIG_CPU_IDLE
38 
39 #define OMAP3_MAX_STATES 7
40 #define OMAP3_STATE_C1 0 /* C1 - MPU WFI + Core active */
41 #define OMAP3_STATE_C2 1 /* C2 - MPU WFI + Core inactive */
42 #define OMAP3_STATE_C3 2 /* C3 - MPU CSWR + Core inactive */
43 #define OMAP3_STATE_C4 3 /* C4 - MPU OFF + Core iactive */
44 #define OMAP3_STATE_C5 4 /* C5 - MPU RET + Core RET */
45 #define OMAP3_STATE_C6 5 /* C6 - MPU OFF + Core RET */
46 #define OMAP3_STATE_C7 6 /* C7 - MPU OFF + Core OFF */
47 
48 struct omap3_processor_cx {
49 	u8 valid;
50 	u8 type;
51 	u32 sleep_latency;
52 	u32 wakeup_latency;
53 	u32 mpu_state;
54 	u32 core_state;
55 	u32 threshold;
56 	u32 flags;
57 };
58 
59 struct omap3_processor_cx omap3_power_states[OMAP3_MAX_STATES];
60 struct omap3_processor_cx current_cx_state;
61 struct powerdomain *mpu_pd, *core_pd;
62 
63 static int omap3_idle_bm_check(void)
64 {
65 	if (!omap3_can_sleep())
66 		return 1;
67 	return 0;
68 }
69 
70 static int _cpuidle_allow_idle(struct powerdomain *pwrdm,
71 				struct clockdomain *clkdm)
72 {
73 	omap2_clkdm_allow_idle(clkdm);
74 	return 0;
75 }
76 
77 static int _cpuidle_deny_idle(struct powerdomain *pwrdm,
78 				struct clockdomain *clkdm)
79 {
80 	omap2_clkdm_deny_idle(clkdm);
81 	return 0;
82 }
83 
84 /**
85  * omap3_enter_idle - Programs OMAP3 to enter the specified state
86  * @dev: cpuidle device
87  * @state: The target state to be programmed
88  *
89  * Called from the CPUidle framework to program the device to the
90  * specified target state selected by the governor.
91  */
92 static int omap3_enter_idle(struct cpuidle_device *dev,
93 			struct cpuidle_state *state)
94 {
95 	struct omap3_processor_cx *cx = cpuidle_get_statedata(state);
96 	struct timespec ts_preidle, ts_postidle, ts_idle;
97 	u32 mpu_state = cx->mpu_state, core_state = cx->core_state;
98 
99 	current_cx_state = *cx;
100 
101 	/* Used to keep track of the total time in idle */
102 	getnstimeofday(&ts_preidle);
103 
104 	local_irq_disable();
105 	local_fiq_disable();
106 
107 	if (!enable_off_mode) {
108 		if (mpu_state < PWRDM_POWER_RET)
109 			mpu_state = PWRDM_POWER_RET;
110 		if (core_state < PWRDM_POWER_RET)
111 			core_state = PWRDM_POWER_RET;
112 	}
113 
114 	pwrdm_set_next_pwrst(mpu_pd, mpu_state);
115 	pwrdm_set_next_pwrst(core_pd, core_state);
116 
117 	if (omap_irq_pending() || need_resched())
118 		goto return_sleep_time;
119 
120 	if (cx->type == OMAP3_STATE_C1) {
121 		pwrdm_for_each_clkdm(mpu_pd, _cpuidle_deny_idle);
122 		pwrdm_for_each_clkdm(core_pd, _cpuidle_deny_idle);
123 	}
124 
125 	/* Execute ARM wfi */
126 	omap_sram_idle();
127 
128 	if (cx->type == OMAP3_STATE_C1) {
129 		pwrdm_for_each_clkdm(mpu_pd, _cpuidle_allow_idle);
130 		pwrdm_for_each_clkdm(core_pd, _cpuidle_allow_idle);
131 	}
132 
133 return_sleep_time:
134 	getnstimeofday(&ts_postidle);
135 	ts_idle = timespec_sub(ts_postidle, ts_preidle);
136 
137 	local_irq_enable();
138 	local_fiq_enable();
139 
140 	return (u32)timespec_to_ns(&ts_idle)/1000;
141 }
142 
143 /**
144  * omap3_enter_idle_bm - Checks for any bus activity
145  * @dev: cpuidle device
146  * @state: The target state to be programmed
147  *
148  * Used for C states with CPUIDLE_FLAG_CHECK_BM flag set. This
149  * function checks for any pending activity and then programs the
150  * device to the specified or a safer state.
151  */
152 static int omap3_enter_idle_bm(struct cpuidle_device *dev,
153 			       struct cpuidle_state *state)
154 {
155 	struct cpuidle_state *new_state = state;
156 
157 	if ((state->flags & CPUIDLE_FLAG_CHECK_BM) && omap3_idle_bm_check()) {
158 		BUG_ON(!dev->safe_state);
159 		new_state = dev->safe_state;
160 	}
161 
162 	dev->last_state = new_state;
163 	return omap3_enter_idle(dev, new_state);
164 }
165 
166 DEFINE_PER_CPU(struct cpuidle_device, omap3_idle_dev);
167 
168 /* omap3_init_power_states - Initialises the OMAP3 specific C states.
169  *
170  * Below is the desciption of each C state.
171  * 	C1 . MPU WFI + Core active
172  *	C2 . MPU WFI + Core inactive
173  *	C3 . MPU CSWR + Core inactive
174  *	C4 . MPU OFF + Core inactive
175  *	C5 . MPU CSWR + Core CSWR
176  *	C6 . MPU OFF + Core CSWR
177  *	C7 . MPU OFF + Core OFF
178  */
179 void omap_init_power_states(void)
180 {
181 	/* C1 . MPU WFI + Core active */
182 	omap3_power_states[OMAP3_STATE_C1].valid = 1;
183 	omap3_power_states[OMAP3_STATE_C1].type = OMAP3_STATE_C1;
184 	omap3_power_states[OMAP3_STATE_C1].sleep_latency = 2;
185 	omap3_power_states[OMAP3_STATE_C1].wakeup_latency = 2;
186 	omap3_power_states[OMAP3_STATE_C1].threshold = 5;
187 	omap3_power_states[OMAP3_STATE_C1].mpu_state = PWRDM_POWER_ON;
188 	omap3_power_states[OMAP3_STATE_C1].core_state = PWRDM_POWER_ON;
189 	omap3_power_states[OMAP3_STATE_C1].flags = CPUIDLE_FLAG_TIME_VALID;
190 
191 	/* C2 . MPU WFI + Core inactive */
192 	omap3_power_states[OMAP3_STATE_C2].valid = 1;
193 	omap3_power_states[OMAP3_STATE_C2].type = OMAP3_STATE_C2;
194 	omap3_power_states[OMAP3_STATE_C2].sleep_latency = 10;
195 	omap3_power_states[OMAP3_STATE_C2].wakeup_latency = 10;
196 	omap3_power_states[OMAP3_STATE_C2].threshold = 30;
197 	omap3_power_states[OMAP3_STATE_C2].mpu_state = PWRDM_POWER_ON;
198 	omap3_power_states[OMAP3_STATE_C2].core_state = PWRDM_POWER_ON;
199 	omap3_power_states[OMAP3_STATE_C2].flags = CPUIDLE_FLAG_TIME_VALID;
200 
201 	/* C3 . MPU CSWR + Core inactive */
202 	omap3_power_states[OMAP3_STATE_C3].valid = 1;
203 	omap3_power_states[OMAP3_STATE_C3].type = OMAP3_STATE_C3;
204 	omap3_power_states[OMAP3_STATE_C3].sleep_latency = 50;
205 	omap3_power_states[OMAP3_STATE_C3].wakeup_latency = 50;
206 	omap3_power_states[OMAP3_STATE_C3].threshold = 300;
207 	omap3_power_states[OMAP3_STATE_C3].mpu_state = PWRDM_POWER_RET;
208 	omap3_power_states[OMAP3_STATE_C3].core_state = PWRDM_POWER_ON;
209 	omap3_power_states[OMAP3_STATE_C3].flags = CPUIDLE_FLAG_TIME_VALID |
210 				CPUIDLE_FLAG_CHECK_BM;
211 
212 	/* C4 . MPU OFF + Core inactive */
213 	omap3_power_states[OMAP3_STATE_C4].valid = 1;
214 	omap3_power_states[OMAP3_STATE_C4].type = OMAP3_STATE_C4;
215 	omap3_power_states[OMAP3_STATE_C4].sleep_latency = 1500;
216 	omap3_power_states[OMAP3_STATE_C4].wakeup_latency = 1800;
217 	omap3_power_states[OMAP3_STATE_C4].threshold = 4000;
218 	omap3_power_states[OMAP3_STATE_C4].mpu_state = PWRDM_POWER_OFF;
219 	omap3_power_states[OMAP3_STATE_C4].core_state = PWRDM_POWER_ON;
220 	omap3_power_states[OMAP3_STATE_C4].flags = CPUIDLE_FLAG_TIME_VALID |
221 				CPUIDLE_FLAG_CHECK_BM;
222 
223 	/* C5 . MPU CSWR + Core CSWR*/
224 	omap3_power_states[OMAP3_STATE_C5].valid = 1;
225 	omap3_power_states[OMAP3_STATE_C5].type = OMAP3_STATE_C5;
226 	omap3_power_states[OMAP3_STATE_C5].sleep_latency = 2500;
227 	omap3_power_states[OMAP3_STATE_C5].wakeup_latency = 7500;
228 	omap3_power_states[OMAP3_STATE_C5].threshold = 12000;
229 	omap3_power_states[OMAP3_STATE_C5].mpu_state = PWRDM_POWER_RET;
230 	omap3_power_states[OMAP3_STATE_C5].core_state = PWRDM_POWER_RET;
231 	omap3_power_states[OMAP3_STATE_C5].flags = CPUIDLE_FLAG_TIME_VALID |
232 				CPUIDLE_FLAG_CHECK_BM;
233 
234 	/* C6 . MPU OFF + Core CSWR */
235 	omap3_power_states[OMAP3_STATE_C6].valid = 1;
236 	omap3_power_states[OMAP3_STATE_C6].type = OMAP3_STATE_C6;
237 	omap3_power_states[OMAP3_STATE_C6].sleep_latency = 3000;
238 	omap3_power_states[OMAP3_STATE_C6].wakeup_latency = 8500;
239 	omap3_power_states[OMAP3_STATE_C6].threshold = 15000;
240 	omap3_power_states[OMAP3_STATE_C6].mpu_state = PWRDM_POWER_OFF;
241 	omap3_power_states[OMAP3_STATE_C6].core_state = PWRDM_POWER_RET;
242 	omap3_power_states[OMAP3_STATE_C6].flags = CPUIDLE_FLAG_TIME_VALID |
243 				CPUIDLE_FLAG_CHECK_BM;
244 
245 	/* C7 . MPU OFF + Core OFF */
246 	omap3_power_states[OMAP3_STATE_C7].valid = 1;
247 	omap3_power_states[OMAP3_STATE_C7].type = OMAP3_STATE_C7;
248 	omap3_power_states[OMAP3_STATE_C7].sleep_latency = 10000;
249 	omap3_power_states[OMAP3_STATE_C7].wakeup_latency = 30000;
250 	omap3_power_states[OMAP3_STATE_C7].threshold = 300000;
251 	omap3_power_states[OMAP3_STATE_C7].mpu_state = PWRDM_POWER_OFF;
252 	omap3_power_states[OMAP3_STATE_C7].core_state = PWRDM_POWER_OFF;
253 	omap3_power_states[OMAP3_STATE_C7].flags = CPUIDLE_FLAG_TIME_VALID |
254 				CPUIDLE_FLAG_CHECK_BM;
255 }
256 
257 struct cpuidle_driver omap3_idle_driver = {
258 	.name = 	"omap3_idle",
259 	.owner = 	THIS_MODULE,
260 };
261 
262 /**
263  * omap3_idle_init - Init routine for OMAP3 idle
264  *
265  * Registers the OMAP3 specific cpuidle driver with the cpuidle
266  * framework with the valid set of states.
267  */
268 int __init omap3_idle_init(void)
269 {
270 	int i, count = 0;
271 	struct omap3_processor_cx *cx;
272 	struct cpuidle_state *state;
273 	struct cpuidle_device *dev;
274 
275 	mpu_pd = pwrdm_lookup("mpu_pwrdm");
276 	core_pd = pwrdm_lookup("core_pwrdm");
277 
278 	omap_init_power_states();
279 	cpuidle_register_driver(&omap3_idle_driver);
280 
281 	dev = &per_cpu(omap3_idle_dev, smp_processor_id());
282 
283 	for (i = OMAP3_STATE_C1; i < OMAP3_MAX_STATES; i++) {
284 		cx = &omap3_power_states[i];
285 		state = &dev->states[count];
286 
287 		if (!cx->valid)
288 			continue;
289 		cpuidle_set_statedata(state, cx);
290 		state->exit_latency = cx->sleep_latency + cx->wakeup_latency;
291 		state->target_residency = cx->threshold;
292 		state->flags = cx->flags;
293 		state->enter = (state->flags & CPUIDLE_FLAG_CHECK_BM) ?
294 			omap3_enter_idle_bm : omap3_enter_idle;
295 		if (cx->type == OMAP3_STATE_C1)
296 			dev->safe_state = state;
297 		sprintf(state->name, "C%d", count+1);
298 		count++;
299 	}
300 
301 	if (!count)
302 		return -EINVAL;
303 	dev->state_count = count;
304 
305 	if (cpuidle_register_device(dev)) {
306 		printk(KERN_ERR "%s: CPUidle register device failed\n",
307 		       __func__);
308 		return -EIO;
309 	}
310 
311 	return 0;
312 }
313 #else
314 int __init omap3_idle_init(void)
315 {
316 	return 0;
317 }
318 #endif /* CONFIG_CPU_IDLE */
319