blob: 1703593e366ccd82452c080bc76c8ba56d6ada27 [file] [log] [blame]
Thomas Abraham91cfbd42012-01-27 15:25:00 +09001/*
2 * Exynos Generic power domain support.
3 *
4 * Copyright (c) 2012 Samsung Electronics Co., Ltd.
5 * http://www.samsung.com
6 *
7 * Implementation of Exynos specific power domain control which is used in
8 * conjunction with runtime-pm. Support for both device-tree and non-device-tree
9 * based power domain support is included.
10 *
11 * This program is free software; you can redistribute it and/or modify
12 * it under the terms of the GNU General Public License version 2 as
13 * published by the Free Software Foundation.
14*/
15
16#include <linux/io.h>
17#include <linux/err.h>
18#include <linux/slab.h>
19#include <linux/pm_domain.h>
20#include <linux/delay.h>
21#include <linux/of_address.h>
Tomasz Figa8a65d232012-11-22 00:21:17 +090022#include <linux/of_platform.h>
23#include <linux/sched.h>
Thomas Abraham91cfbd42012-01-27 15:25:00 +090024
25#include <mach/regs-pmu.h>
26#include <plat/devs.h>
27
28/*
29 * Exynos specific wrapper around the generic power domain
30 */
31struct exynos_pm_domain {
32 void __iomem *base;
33 char const *name;
34 bool is_off;
35 struct generic_pm_domain pd;
36};
37
38static int exynos_pd_power(struct generic_pm_domain *domain, bool power_on)
39{
40 struct exynos_pm_domain *pd;
41 void __iomem *base;
42 u32 timeout, pwr;
43 char *op;
44
45 pd = container_of(domain, struct exynos_pm_domain, pd);
46 base = pd->base;
47
48 pwr = power_on ? S5P_INT_LOCAL_PWR_EN : 0;
49 __raw_writel(pwr, base);
50
51 /* Wait max 1ms */
52 timeout = 10;
53
54 while ((__raw_readl(base + 0x4) & S5P_INT_LOCAL_PWR_EN) != pwr) {
55 if (!timeout) {
56 op = (power_on) ? "enable" : "disable";
57 pr_err("Power domain %s %s failed\n", domain->name, op);
58 return -ETIMEDOUT;
59 }
60 timeout--;
61 cpu_relax();
62 usleep_range(80, 100);
63 }
64 return 0;
65}
66
67static int exynos_pd_power_on(struct generic_pm_domain *domain)
68{
69 return exynos_pd_power(domain, true);
70}
71
72static int exynos_pd_power_off(struct generic_pm_domain *domain)
73{
74 return exynos_pd_power(domain, false);
75}
76
Tomasz Figa8a65d232012-11-22 00:21:17 +090077static void exynos_add_device_to_domain(struct exynos_pm_domain *pd,
78 struct device *dev)
79{
80 int ret;
81
82 dev_dbg(dev, "adding to power domain %s\n", pd->pd.name);
83
84 while (1) {
85 ret = pm_genpd_add_device(&pd->pd, dev);
86 if (ret != -EAGAIN)
87 break;
88 cond_resched();
89 }
90
91 pm_genpd_dev_need_restore(dev, true);
92}
93
94static void exynos_remove_device_from_domain(struct device *dev)
95{
96 struct generic_pm_domain *genpd = dev_to_genpd(dev);
97 int ret;
98
99 dev_dbg(dev, "removing from power domain %s\n", genpd->name);
100
101 while (1) {
102 ret = pm_genpd_remove_device(genpd, dev);
103 if (ret != -EAGAIN)
104 break;
105 cond_resched();
106 }
107}
108
109static void exynos_read_domain_from_dt(struct device *dev)
110{
111 struct platform_device *pd_pdev;
112 struct exynos_pm_domain *pd;
113 struct device_node *node;
114
115 node = of_parse_phandle(dev->of_node, "samsung,power-domain", 0);
116 if (!node)
117 return;
118 pd_pdev = of_find_device_by_node(node);
119 if (!pd_pdev)
120 return;
121 pd = platform_get_drvdata(pd_pdev);
122 exynos_add_device_to_domain(pd, dev);
123}
124
125static int exynos_pm_notifier_call(struct notifier_block *nb,
126 unsigned long event, void *data)
127{
128 struct device *dev = data;
129
130 switch (event) {
131 case BUS_NOTIFY_BIND_DRIVER:
132 if (dev->of_node)
133 exynos_read_domain_from_dt(dev);
134
135 break;
136
137 case BUS_NOTIFY_UNBOUND_DRIVER:
138 exynos_remove_device_from_domain(dev);
139
140 break;
141 }
142 return NOTIFY_DONE;
143}
144
145static struct notifier_block platform_nb = {
146 .notifier_call = exynos_pm_notifier_call,
147};
148
Tomasz Figa8eaa9e42013-06-15 09:13:25 +0900149static __init int exynos4_pm_init_power_domain(void)
Thomas Abraham91cfbd42012-01-27 15:25:00 +0900150{
Tomasz Figa8a65d232012-11-22 00:21:17 +0900151 struct platform_device *pdev;
Thomas Abraham91cfbd42012-01-27 15:25:00 +0900152 struct device_node *np;
153
154 for_each_compatible_node(np, NULL, "samsung,exynos4210-pd") {
155 struct exynos_pm_domain *pd;
Tomasz Figa2ed5f232012-11-22 00:21:08 +0900156 int on;
Thomas Abraham91cfbd42012-01-27 15:25:00 +0900157
Tomasz Figa8a65d232012-11-22 00:21:17 +0900158 pdev = of_find_device_by_node(np);
159
Thomas Abraham91cfbd42012-01-27 15:25:00 +0900160 pd = kzalloc(sizeof(*pd), GFP_KERNEL);
161 if (!pd) {
162 pr_err("%s: failed to allocate memory for domain\n",
163 __func__);
164 return -ENOMEM;
165 }
166
Tomasz Figa7add0ec2012-11-22 00:21:12 +0900167 pd->pd.name = kstrdup(np->name, GFP_KERNEL);
168 pd->name = pd->pd.name;
Thomas Abraham91cfbd42012-01-27 15:25:00 +0900169 pd->base = of_iomap(np, 0);
170 pd->pd.power_off = exynos_pd_power_off;
171 pd->pd.power_on = exynos_pd_power_on;
172 pd->pd.of_node = np;
Tomasz Figa2ed5f232012-11-22 00:21:08 +0900173
Tomasz Figa8a65d232012-11-22 00:21:17 +0900174 platform_set_drvdata(pdev, pd);
175
Tomasz Figa2ed5f232012-11-22 00:21:08 +0900176 on = __raw_readl(pd->base + 0x4) & S5P_INT_LOCAL_PWR_EN;
177
178 pm_genpd_init(&pd->pd, NULL, !on);
Thomas Abraham91cfbd42012-01-27 15:25:00 +0900179 }
Tomasz Figa8a65d232012-11-22 00:21:17 +0900180
181 bus_register_notifier(&platform_bus_type, &platform_nb);
182
Thomas Abraham91cfbd42012-01-27 15:25:00 +0900183 return 0;
184}
Thomas Abraham91cfbd42012-01-27 15:25:00 +0900185arch_initcall(exynos4_pm_init_power_domain);
186
Shawn Guobb13fab2012-04-26 10:35:40 +0800187int __init exynos_pm_late_initcall(void)
Thomas Abraham91cfbd42012-01-27 15:25:00 +0900188{
189 pm_genpd_poweroff_unused();
190 return 0;
191}