ARM: OMAP4: PM: Keep static dep between MPUSS-EMIF and MPUSS-L3/L4 and DUCATI-L3
[linux-2.6.git] / arch / arm / mach-omap2 / pm44xx.c
1 /*
2  * OMAP4 Power Management Routines
3  *
4  * Copyright (C) 2010 Texas Instruments, Inc.
5  * Rajendra Nayak <rnayak@ti.com>
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/pm.h>
13 #include <linux/suspend.h>
14 #include <linux/module.h>
15 #include <linux/list.h>
16 #include <linux/err.h>
17 #include <linux/slab.h>
18
19 #include "common.h"
20 #include "powerdomain.h"
21
22 struct power_state {
23         struct powerdomain *pwrdm;
24         u32 next_state;
25 #ifdef CONFIG_SUSPEND
26         u32 saved_state;
27 #endif
28         struct list_head node;
29 };
30
31 static LIST_HEAD(pwrst_list);
32
33 #ifdef CONFIG_SUSPEND
34 static int omap4_pm_suspend(void)
35 {
36         do_wfi();
37         return 0;
38 }
39
40 static int omap4_pm_enter(suspend_state_t suspend_state)
41 {
42         int ret = 0;
43
44         switch (suspend_state) {
45         case PM_SUSPEND_STANDBY:
46         case PM_SUSPEND_MEM:
47                 ret = omap4_pm_suspend();
48                 break;
49         default:
50                 ret = -EINVAL;
51         }
52
53         return ret;
54 }
55
56 static int omap4_pm_begin(suspend_state_t state)
57 {
58         disable_hlt();
59         return 0;
60 }
61
62 static void omap4_pm_end(void)
63 {
64         enable_hlt();
65         return;
66 }
67
68 static const struct platform_suspend_ops omap_pm_ops = {
69         .begin          = omap4_pm_begin,
70         .end            = omap4_pm_end,
71         .enter          = omap4_pm_enter,
72         .valid          = suspend_valid_only_mem,
73 };
74 #endif /* CONFIG_SUSPEND */
75
76 static int __init pwrdms_setup(struct powerdomain *pwrdm, void *unused)
77 {
78         struct power_state *pwrst;
79
80         if (!pwrdm->pwrsts)
81                 return 0;
82
83         pwrst = kmalloc(sizeof(struct power_state), GFP_ATOMIC);
84         if (!pwrst)
85                 return -ENOMEM;
86         pwrst->pwrdm = pwrdm;
87         pwrst->next_state = PWRDM_POWER_ON;
88         list_add(&pwrst->node, &pwrst_list);
89
90         return pwrdm_set_next_pwrst(pwrst->pwrdm, pwrst->next_state);
91 }
92
93 /**
94  * omap4_pm_init - Init routine for OMAP4 PM
95  *
96  * Initializes all powerdomain and clockdomain target states
97  * and all PRCM settings.
98  */
99 static int __init omap4_pm_init(void)
100 {
101         int ret;
102         struct clockdomain *emif_clkdm, *mpuss_clkdm, *l3_1_clkdm;
103         struct clockdomain *ducati_clkdm, *l3_2_clkdm, *l4_per_clkdm;
104
105         if (!cpu_is_omap44xx())
106                 return -ENODEV;
107
108         pr_err("Power Management for TI OMAP4.\n");
109
110         ret = pwrdm_for_each(pwrdms_setup, NULL);
111         if (ret) {
112                 pr_err("Failed to setup powerdomains\n");
113                 goto err2;
114         }
115
116         /*
117          * The dynamic dependency between MPUSS -> MEMIF and
118          * MPUSS -> L4_PER/L3_* and DUCATI -> L3_* doesn't work as
119          * expected. The hardware recommendation is to enable static
120          * dependencies for these to avoid system lock ups or random crashes.
121          */
122         mpuss_clkdm = clkdm_lookup("mpuss_clkdm");
123         emif_clkdm = clkdm_lookup("l3_emif_clkdm");
124         l3_1_clkdm = clkdm_lookup("l3_1_clkdm");
125         l3_2_clkdm = clkdm_lookup("l3_2_clkdm");
126         l4_per_clkdm = clkdm_lookup("l4_per_clkdm");
127         ducati_clkdm = clkdm_lookup("ducati_clkdm");
128         if ((!mpuss_clkdm) || (!emif_clkdm) || (!l3_1_clkdm) ||
129                 (!l3_2_clkdm) || (!ducati_clkdm) || (!l4_per_clkdm))
130                 goto err2;
131
132         ret = clkdm_add_wkdep(mpuss_clkdm, emif_clkdm);
133         ret |= clkdm_add_wkdep(mpuss_clkdm, l3_1_clkdm);
134         ret |= clkdm_add_wkdep(mpuss_clkdm, l3_2_clkdm);
135         ret |= clkdm_add_wkdep(mpuss_clkdm, l4_per_clkdm);
136         ret |= clkdm_add_wkdep(ducati_clkdm, l3_1_clkdm);
137         ret |= clkdm_add_wkdep(ducati_clkdm, l3_2_clkdm);
138         if (ret) {
139                 pr_err("Failed to add MPUSS -> L3/EMIF/L4PER, DUCATI -> L3 "
140                                 "wakeup dependency\n");
141                 goto err2;
142         }
143
144 #ifdef CONFIG_SUSPEND
145         suspend_set_ops(&omap_pm_ops);
146 #endif /* CONFIG_SUSPEND */
147
148 err2:
149         return ret;
150 }
151 late_initcall(omap4_pm_init);