5113f6f70
 김현기
kernel add
|
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
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
|
/*
* CPPC (Collaborative Processor Performance Control) driver for
* interfacing with the CPUfreq layer and governors. See
* cppc_acpi.c for CPPC specific methods.
*
* (C) Copyright 2014, 2015 Linaro Ltd.
* Author: Ashwin Chaugule <ashwin.chaugule@linaro.org>
*
* 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.
*/
#define pr_fmt(fmt) "CPPC Cpufreq:" fmt
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/delay.h>
#include <linux/cpu.h>
#include <linux/cpufreq.h>
#include <linux/vmalloc.h>
#include <acpi/cppc_acpi.h>
/*
* These structs contain information parsed from per CPU
* ACPI _CPC structures.
* e.g. For each CPU the highest, lowest supported
* performance capabilities, desired performance level
* requested etc.
*/
static struct cpudata **all_cpu_data;
static int cppc_cpufreq_set_target(struct cpufreq_policy *policy,
unsigned int target_freq,
unsigned int relation)
{
struct cpudata *cpu;
struct cpufreq_freqs freqs;
int ret = 0;
cpu = all_cpu_data[policy->cpu];
cpu->perf_ctrls.desired_perf = target_freq;
freqs.old = policy->cur;
freqs.new = target_freq;
cpufreq_freq_transition_begin(policy, &freqs);
ret = cppc_set_perf(cpu->cpu, &cpu->perf_ctrls);
cpufreq_freq_transition_end(policy, &freqs, ret != 0);
if (ret)
pr_debug("Failed to set target on CPU:%d. ret:%d
",
cpu->cpu, ret);
return ret;
}
static int cppc_verify_policy(struct cpufreq_policy *policy)
{
cpufreq_verify_within_cpu_limits(policy);
return 0;
}
static void cppc_cpufreq_stop_cpu(struct cpufreq_policy *policy)
{
int cpu_num = policy->cpu;
struct cpudata *cpu = all_cpu_data[cpu_num];
int ret;
cpu->perf_ctrls.desired_perf = cpu->perf_caps.lowest_perf;
ret = cppc_set_perf(cpu_num, &cpu->perf_ctrls);
if (ret)
pr_debug("Err setting perf value:%d on CPU:%d. ret:%d
",
cpu->perf_caps.lowest_perf, cpu_num, ret);
}
static int cppc_cpufreq_cpu_init(struct cpufreq_policy *policy)
{
struct cpudata *cpu;
unsigned int cpu_num = policy->cpu;
int ret = 0;
cpu = all_cpu_data[policy->cpu];
cpu->cpu = cpu_num;
ret = cppc_get_perf_caps(policy->cpu, &cpu->perf_caps);
if (ret) {
pr_debug("Err reading CPU%d perf capabilities. ret:%d
",
cpu_num, ret);
return ret;
}
policy->min = cpu->perf_caps.lowest_perf;
policy->max = cpu->perf_caps.highest_perf;
policy->cpuinfo.min_freq = policy->min;
policy->cpuinfo.max_freq = policy->max;
policy->shared_type = cpu->shared_type;
if (policy->shared_type == CPUFREQ_SHARED_TYPE_ANY)
cpumask_copy(policy->cpus, cpu->shared_cpu_map);
else if (policy->shared_type == CPUFREQ_SHARED_TYPE_ALL) {
/* Support only SW_ANY for now. */
pr_debug("Unsupported CPU co-ord type
");
return -EFAULT;
}
cpumask_set_cpu(policy->cpu, policy->cpus);
cpu->cur_policy = policy;
/* Set policy->cur to max now. The governors will adjust later. */
policy->cur = cpu->perf_ctrls.desired_perf = cpu->perf_caps.highest_perf;
ret = cppc_set_perf(cpu_num, &cpu->perf_ctrls);
if (ret)
pr_debug("Err setting perf value:%d on CPU:%d. ret:%d
",
cpu->perf_caps.highest_perf, cpu_num, ret);
return ret;
}
static struct cpufreq_driver cppc_cpufreq_driver = {
.flags = CPUFREQ_CONST_LOOPS,
.verify = cppc_verify_policy,
.target = cppc_cpufreq_set_target,
.init = cppc_cpufreq_cpu_init,
.stop_cpu = cppc_cpufreq_stop_cpu,
.name = "cppc_cpufreq",
};
static int __init cppc_cpufreq_init(void)
{
int i, ret = 0;
struct cpudata *cpu;
if (acpi_disabled)
return -ENODEV;
all_cpu_data = kzalloc(sizeof(void *) * num_possible_cpus(), GFP_KERNEL);
if (!all_cpu_data)
return -ENOMEM;
for_each_possible_cpu(i) {
all_cpu_data[i] = kzalloc(sizeof(struct cpudata), GFP_KERNEL);
if (!all_cpu_data[i])
goto out;
cpu = all_cpu_data[i];
if (!zalloc_cpumask_var(&cpu->shared_cpu_map, GFP_KERNEL))
goto out;
}
ret = acpi_get_psd_map(all_cpu_data);
if (ret) {
pr_debug("Error parsing PSD data. Aborting cpufreq registration.
");
goto out;
}
ret = cpufreq_register_driver(&cppc_cpufreq_driver);
if (ret)
goto out;
return ret;
out:
for_each_possible_cpu(i)
kfree(all_cpu_data[i]);
kfree(all_cpu_data);
return -ENODEV;
}
late_initcall(cppc_cpufreq_init);
|