1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
|
/*
* drivers/cpuidle/cpuidle-denver.c
*
* Copyright (C) 2013 NVIDIA Corporation. All rights reserved.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; version 2 of the License.
*
* This program is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
* more details.
*
* You should have received a copy of the GNU General Public License along
* with this program; if not, write to the Free Software Foundation, Inc.,
* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
*
*/
#include <linux/kernel.h>
#include <linux/cpuidle.h>
#include <linux/slab.h>
#include <linux/module.h>
#include <linux/of_platform.h>
void tegra_pd_in_idle(bool enable) {}
static int pmstate_map[CPUIDLE_STATE_MAX] = { -1 };
static int denver_enter_c_state(
struct cpuidle_device *dev,
struct cpuidle_driver *drv,
int index)
{
uintptr_t pmstate = pmstate_map[index];
BUG_ON(pmstate < 0);
asm volatile("msr actlr_el1, %0\n" : : "r" (pmstate));
asm volatile("wfi\n");
local_irq_enable();
return 0;
}
static struct cpuidle_driver denver_idle_driver = {
.name = "denver_idle",
.owner = THIS_MODULE,
};
static int __init denver_power_states_init(void)
{
struct device_node *of_states;
struct device_node *child;
struct cpuidle_state *state;
const char *name;
u32 state_count = 0;
u32 prop;
of_states = of_find_node_by_name(NULL, "denver_power_states");
if (!of_states)
return -ENODEV;
for_each_child_of_node(of_states, child) {
state = &denver_idle_driver.states[state_count];
if (of_property_read_string(child, "state-name", &name))
continue;
snprintf(state->name, CPUIDLE_NAME_LEN, child->name);
snprintf(state->desc, CPUIDLE_DESC_LEN, name);
if (of_property_read_u32(child, "latency", &prop) == 0)
state->exit_latency = prop;
if (of_property_read_u32(
child, "residency", &prop) == 0) {
state->flags = CPUIDLE_FLAG_TIME_VALID;
state->target_residency = prop;
}
if (of_property_read_u32(child, "power", &prop) != 0)
state->exit_latency = prop;
state->enter = denver_enter_c_state;
/* Map index to the actual LP state */
if (of_property_read_u32(child, "pmstate", &prop) != 0)
continue;
pmstate_map[state_count] = prop;
state_count++;
}
denver_idle_driver.state_count = state_count;
return cpuidle_register_driver(&denver_idle_driver);
}
static int __init denver_cpuidle_devices_init(void)
{
struct device_node *cpu = NULL;
struct device_node *of_states;
struct cpuidle_device *dev;
u64 cpu_reg;
for_each_node_by_type(cpu, "cpu") {
if (!of_device_is_compatible(cpu, "nvidia,denver"))
continue;
of_states = of_parse_phandle(cpu, "power-states", 0);
if (!of_states || !of_device_is_compatible(
of_states, "nvidia,denver"))
continue;
dev = kzalloc(sizeof(*dev), GFP_KERNEL);
if (!dev)
return -ENOMEM;
BUG_ON(of_property_read_u64(cpu, "reg", &cpu_reg));
dev->cpu = (unsigned long)cpu_reg;
dev->state_count = denver_idle_driver.state_count;
if (cpuidle_register_device(dev)) {
pr_err("%s: failed to register idle device\n",
cpu->full_name);
kfree(dev);
return -EIO;
}
}
return 0;
}
static int __init denver_cpuidle_init(void)
{
int e;
e = denver_power_states_init();
if (e) {
pr_err("%s: failed to init cpuidle power states.\n", __func__);
return e;
}
e = denver_cpuidle_devices_init();
if (e) {
pr_err("%s: failed to init cpuidle devices.\n", __func__);
return e;
}
return 0;
}
device_initcall(denver_cpuidle_init);
|
