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
|
/*
* System Control and Power Interface (SCPI) based CPUFreq Interface driver
*
* It provides necessary ops to arm_big_little cpufreq driver.
*
* Copyright (C) 2015 ARM Ltd.
* Sudeep Holla <sudeep.holla@arm.com>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*
* This program is distributed "as is" WITHOUT ANY WARRANTY of any
* kind, whether express or implied; without even the implied warranty
* of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*/
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
#include <linux/cpufreq.h>
#include <linux/module.h>
#include <linux/platform_device.h>
#include <linux/pm_opp.h>
#include <linux/scpi_protocol.h>
#include <linux/types.h>
#include "arm_big_little.h"
static struct scpi_ops *scpi_ops;
static struct scpi_dvfs_info *scpi_get_dvfs_info(struct device *cpu_dev)
{
int domain = topology_physical_package_id(cpu_dev->id);
if (domain < 0)
return ERR_PTR(-EINVAL);
return scpi_ops->dvfs_get_info(domain);
}
static int scpi_opp_table_ops(struct device *cpu_dev, bool remove)
{
int idx, ret = 0;
struct scpi_opp *opp;
struct scpi_dvfs_info *info = scpi_get_dvfs_info(cpu_dev);
if (IS_ERR(info))
return PTR_ERR(info);
if (!info->opps)
return -EIO;
for (opp = info->opps, idx = 0; idx < info->count; idx++, opp++) {
if (remove)
dev_pm_opp_remove(cpu_dev, opp->freq);
else
ret = dev_pm_opp_add(cpu_dev, opp->freq,
opp->m_volt * 1000);
if (ret) {
dev_warn(cpu_dev, "failed to add opp %uHz %umV\n",
opp->freq, opp->m_volt);
while (idx-- > 0)
dev_pm_opp_remove(cpu_dev, (--opp)->freq);
return ret;
}
}
return ret;
}
static int scpi_get_transition_latency(struct device *cpu_dev)
{
struct scpi_dvfs_info *info = scpi_get_dvfs_info(cpu_dev);
if (IS_ERR(info))
return PTR_ERR(info);
return info->latency;
}
static int scpi_init_opp_table(struct device *cpu_dev)
{
return scpi_opp_table_ops(cpu_dev, false);
}
static void scpi_free_opp_table(struct device *cpu_dev)
{
scpi_opp_table_ops(cpu_dev, true);
}
static struct cpufreq_arm_bL_ops scpi_cpufreq_ops = {
.name = "scpi",
.get_transition_latency = scpi_get_transition_latency,
.init_opp_table = scpi_init_opp_table,
.free_opp_table = scpi_free_opp_table,
};
static int scpi_cpufreq_probe(struct platform_device *pdev)
{
scpi_ops = get_scpi_ops();
if (!scpi_ops)
return -EIO;
return bL_cpufreq_register(&scpi_cpufreq_ops);
}
static int scpi_cpufreq_remove(struct platform_device *pdev)
{
bL_cpufreq_unregister(&scpi_cpufreq_ops);
scpi_ops = NULL;
return 0;
}
static struct platform_driver scpi_cpufreq_platdrv = {
.driver = {
.name = "scpi-cpufreq",
.owner = THIS_MODULE,
},
.probe = scpi_cpufreq_probe,
.remove = scpi_cpufreq_remove,
};
module_platform_driver(scpi_cpufreq_platdrv);
MODULE_AUTHOR("Sudeep Holla <sudeep.holla@arm.com>");
MODULE_DESCRIPTION("ARM SCPI CPUFreq interface driver");
MODULE_LICENSE("GPL v2");
|