xref: /openbmc/linux/arch/arm/mach-omap2/pm.c (revision baa7eb025ab14f3cba2e35c0a8648f9c9f01d24f)
1 /*
2  * pm.c - Common OMAP2+ power management-related code
3  *
4  * Copyright (C) 2010 Texas Instruments, Inc.
5  * Copyright (C) 2010 Nokia Corporation
6  *
7  * This program is free software; you can redistribute it and/or modify
8  * it under the terms of the GNU General Public License version 2 as
9  * published by the Free Software Foundation.
10  */
11 
12 #include <linux/kernel.h>
13 #include <linux/init.h>
14 #include <linux/io.h>
15 #include <linux/err.h>
16 
17 #include <plat/omap-pm.h>
18 #include <plat/omap_device.h>
19 #include <plat/common.h>
20 
21 #include <plat/powerdomain.h>
22 #include <plat/clockdomain.h>
23 
24 static struct omap_device_pm_latency *pm_lats;
25 
26 static struct device *mpu_dev;
27 static struct device *iva_dev;
28 static struct device *l3_dev;
29 static struct device *dsp_dev;
30 
31 struct device *omap2_get_mpuss_device(void)
32 {
33 	WARN_ON_ONCE(!mpu_dev);
34 	return mpu_dev;
35 }
36 
37 struct device *omap2_get_iva_device(void)
38 {
39 	WARN_ON_ONCE(!iva_dev);
40 	return iva_dev;
41 }
42 
43 struct device *omap2_get_l3_device(void)
44 {
45 	WARN_ON_ONCE(!l3_dev);
46 	return l3_dev;
47 }
48 
49 struct device *omap4_get_dsp_device(void)
50 {
51 	WARN_ON_ONCE(!dsp_dev);
52 	return dsp_dev;
53 }
54 EXPORT_SYMBOL(omap4_get_dsp_device);
55 
56 /* static int _init_omap_device(struct omap_hwmod *oh, void *user) */
57 static int _init_omap_device(char *name, struct device **new_dev)
58 {
59 	struct omap_hwmod *oh;
60 	struct omap_device *od;
61 
62 	oh = omap_hwmod_lookup(name);
63 	if (WARN(!oh, "%s: could not find omap_hwmod for %s\n",
64 		 __func__, name))
65 		return -ENODEV;
66 
67 	od = omap_device_build(oh->name, 0, oh, NULL, 0, pm_lats, 0, false);
68 	if (WARN(IS_ERR(od), "%s: could not build omap_device for %s\n",
69 		 __func__, name))
70 		return -ENODEV;
71 
72 	*new_dev = &od->pdev.dev;
73 
74 	return 0;
75 }
76 
77 /*
78  * Build omap_devices for processors and bus.
79  */
80 static void omap2_init_processor_devices(void)
81 {
82 	_init_omap_device("mpu", &mpu_dev);
83 	_init_omap_device("iva", &iva_dev);
84 	if (cpu_is_omap44xx()) {
85 		_init_omap_device("l3_main_1", &l3_dev);
86 		_init_omap_device("dsp", &dsp_dev);
87 	} else {
88 		_init_omap_device("l3_main", &l3_dev);
89 	}
90 }
91 
92 /*
93  * This sets pwrdm state (other than mpu & core. Currently only ON &
94  * RET are supported. Function is assuming that clkdm doesn't have
95  * hw_sup mode enabled.
96  */
97 int omap_set_pwrdm_state(struct powerdomain *pwrdm, u32 state)
98 {
99 	u32 cur_state;
100 	int sleep_switch = 0;
101 	int ret = 0;
102 
103 	if (pwrdm == NULL || IS_ERR(pwrdm))
104 		return -EINVAL;
105 
106 	while (!(pwrdm->pwrsts & (1 << state))) {
107 		if (state == PWRDM_POWER_OFF)
108 			return ret;
109 		state--;
110 	}
111 
112 	cur_state = pwrdm_read_next_pwrst(pwrdm);
113 	if (cur_state == state)
114 		return ret;
115 
116 	if (pwrdm_read_pwrst(pwrdm) < PWRDM_POWER_ON) {
117 		omap2_clkdm_wakeup(pwrdm->pwrdm_clkdms[0]);
118 		sleep_switch = 1;
119 		pwrdm_wait_transition(pwrdm);
120 	}
121 
122 	ret = pwrdm_set_next_pwrst(pwrdm, state);
123 	if (ret) {
124 		printk(KERN_ERR "Unable to set state of powerdomain: %s\n",
125 		       pwrdm->name);
126 		goto err;
127 	}
128 
129 	if (sleep_switch) {
130 		omap2_clkdm_allow_idle(pwrdm->pwrdm_clkdms[0]);
131 		pwrdm_wait_transition(pwrdm);
132 		pwrdm_state_switch(pwrdm);
133 	}
134 
135 err:
136 	return ret;
137 }
138 
139 static int __init omap2_common_pm_init(void)
140 {
141 	omap2_init_processor_devices();
142 	omap_pm_if_init();
143 
144 	return 0;
145 }
146 device_initcall(omap2_common_pm_init);
147 
148