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
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
|
/*
* Copyright (c) 2006-2022, RT-Thread Development Team
*
* SPDX-License-Identifier: Apache-2.0
*
* Change Logs:
* Date Author Notes
* 2022-11-21 GuEe-GUI first version
*/
#include <rthw.h>
#include <rtthread.h>
#include <rtdevice.h>
#define DBG_TAG "dvfs.governor.ondemand"
#define DBG_LVL DBG_INFO
#include <rtdbg.h>
/* Default parameters (Linux-like) */
#define ONDEMAND_DEFAULT_SAMPLING_RATE_MS 1000
#define ONDEMAND_DEFAULT_UP_THRESHOLD 80
#define ONDEMAND_DEFAULT_DOWN_DIFFERENTIAL 20
#define ONDEMAND_DEFAULT_IGNORE_NICE RT_FALSE
#define ONDEMAND_DEFAULT_POWERSAVE_BIAS 0
struct governor_ondemand_data
{
struct rt_work monitor_work;
rt_bool_t running;
};
static rt_bool_t governor_ondemand_active(struct rt_dvfs_scaling *dvfs)
{
struct governor_ondemand_data *data;
if (!dvfs || !dvfs->gov ||
dvfs->gov->type != RT_DVFS_GOVERNOR_TYPE_ONDEMAND)
{
return RT_FALSE;
}
data = dvfs->gov_data;
return data && data->running;
}
static void governor_ondemand_monitor(struct rt_work *work, void *work_data)
{
struct rt_dvfs_scaling *dvfs = (struct rt_dvfs_scaling *)work_data;
struct governor_ondemand_data *data;
struct rt_dvfs_opp *opp;
rt_ubase_t target_freq;
rt_uint32_t load;
if (!governor_ondemand_active(dvfs))
{
return;
}
data = dvfs->gov_data;
/* Update CPU load statistics */
rt_dvfs_load_update(dvfs);
load = rt_dvfs_cpu_load_get(&dvfs->cpu_load);
/* Determine target frequency based on load */
if (load >= dvfs->gov_params.up_threshold)
{
/* High load: jump to max frequency */
target_freq = dvfs->max_freq;
LOG_D("%s: load=%u%% >= threshold=%u%%, set max freq",
rt_dm_dev_get_name(dvfs->dev), load,
dvfs->gov_params.up_threshold);
}
else if (load < dvfs->gov_params.down_differential)
{
/* Low load: find appropriate frequency */
rt_ubase_t freq_target = (dvfs->cur_freq * load) / 100;
/* Apply powersave bias if configured */
if (dvfs->gov_params.powersave_bias > 0)
{
freq_target = freq_target * (100 - dvfs->gov_params.powersave_bias) / 100;
}
/* Find floor OPP (next lower or equal frequency) */
opp = rt_dvfs_scaling_find_floor_opp(dvfs, freq_target);
if (opp && opp->available)
{
target_freq = opp->freq;
}
else
{
target_freq = dvfs->min_freq;
}
LOG_D("%s: load=%u%% < diff=%u%%, target=%lu Hz",
rt_dm_dev_get_name(dvfs->dev), load,
dvfs->gov_params.down_differential, target_freq);
}
else
{
/* Medium load: keep current frequency */
target_freq = dvfs->cur_freq;
}
/* Set target frequency if different */
if (target_freq != dvfs->cur_freq && governor_ondemand_active(dvfs))
{
rt_err_t err = rt_dvfs_scaling_set_frequency(dvfs, target_freq);
if (err)
{
LOG_W("%s: set frequency %lu failed: %s",
rt_dm_dev_get_name(dvfs->dev), target_freq, rt_strerror(err));
}
}
/* Reschedule monitoring work */
if (governor_ondemand_active(dvfs))
{
rt_work_submit(&data->monitor_work,
rt_tick_from_millisecond(dvfs->gov_params.sampling_rate_ms));
}
}
static rt_err_t governor_ondemand_start(struct rt_dvfs_scaling *dvfs)
{
struct governor_ondemand_data *data;
if (!dvfs)
{
return -RT_EINVAL;
}
/* Initialize default parameters if not set */
if (dvfs->gov_params.sampling_rate_ms == 0)
{
dvfs->gov_params.sampling_rate_ms = ONDEMAND_DEFAULT_SAMPLING_RATE_MS;
}
if (dvfs->gov_params.up_threshold == 0)
{
dvfs->gov_params.up_threshold = ONDEMAND_DEFAULT_UP_THRESHOLD;
}
if (dvfs->gov_params.down_differential == 0)
{
dvfs->gov_params.down_differential = ONDEMAND_DEFAULT_DOWN_DIFFERENTIAL;
}
if (dvfs->gov_params.ignore_nice_load == 0)
{
dvfs->gov_params.ignore_nice_load = ONDEMAND_DEFAULT_IGNORE_NICE;
}
if (dvfs->gov_params.powersave_bias == 0)
{
dvfs->gov_params.powersave_bias = ONDEMAND_DEFAULT_POWERSAVE_BIAS;
}
/* Allocate governor data */
data = rt_calloc(1, sizeof(*data));
if (!data)
{
LOG_E("%s: no memory for ondemand data", rt_dm_dev_get_name(dvfs->dev));
return -RT_ENOMEM;
}
dvfs->gov_data = data;
data->running = RT_TRUE;
/* Initialize CPU load */
dvfs->cpu_load.last_update = rt_tick_get();
dvfs->cpu_load.total_tick = 0;
dvfs->cpu_load.idle_tick = 0;
dvfs->cpu_load.load_percentage = 0;
/* Initialize monitoring work */
rt_work_init(&data->monitor_work, governor_ondemand_monitor, dvfs);
/* Submit first monitoring work */
rt_work_submit(&data->monitor_work,
rt_tick_from_millisecond(dvfs->gov_params.sampling_rate_ms));
LOG_D("%s: ondemand governor started (sampling=%ums, up_threshold=%u%%, down_diff=%u%%)",
rt_dm_dev_get_name(dvfs->dev),
dvfs->gov_params.sampling_rate_ms,
dvfs->gov_params.up_threshold,
dvfs->gov_params.down_differential);
return RT_EOK;
}
static rt_err_t governor_ondemand_stop(struct rt_dvfs_scaling *dvfs)
{
struct governor_ondemand_data *data;
if (!dvfs || !dvfs->gov)
{
return -RT_EINVAL;
}
data = dvfs->gov_data;
if (data)
{
data->running = RT_FALSE;
rt_work_cancel(&data->monitor_work);
/* Wait for work to complete */
rt_thread_mdelay(10);
rt_free(data);
dvfs->gov_data = RT_NULL;
}
LOG_D("%s: ondemand governor stopped", rt_dm_dev_get_name(dvfs->dev));
return RT_EOK;
}
static rt_err_t governor_ondemand_suspend(struct rt_dvfs_scaling *dvfs)
{
struct governor_ondemand_data *data;
if (!dvfs || !dvfs->gov)
{
return -RT_EINVAL;
}
/* Stop monitoring */
data = dvfs->gov_data;
if (data)
{
data->running = RT_FALSE;
rt_work_cancel(&data->monitor_work);
}
return RT_EOK;
}
static rt_err_t governor_ondemand_resume(struct rt_dvfs_scaling *dvfs)
{
struct governor_ondemand_data *data;
if (!dvfs || !dvfs->gov)
{
return -RT_EINVAL;
}
/* Resume monitoring */
data = dvfs->gov_data;
if (data)
{
/* Reset CPU load statistics */
dvfs->cpu_load.last_update = rt_tick_get();
dvfs->cpu_load.total_tick = 0;
dvfs->cpu_load.idle_tick = 0;
data->running = RT_TRUE;
rt_work_submit(&data->monitor_work,
rt_tick_from_millisecond(dvfs->gov_params.sampling_rate_ms));
}
return RT_EOK;
}
static rt_err_t governor_ondemand_set_interval(struct rt_dvfs_scaling *dvfs, rt_uint32_t interval_ms)
{
if (!dvfs)
{
return -RT_EINVAL;
}
/* Minimum sampling interval: 10ms */
if (interval_ms < 10)
{
interval_ms = 10;
}
dvfs->gov_params.sampling_rate_ms = interval_ms;
LOG_D("%s: ondemand sampling interval set to %ums",
rt_dm_dev_get_name(dvfs->dev), interval_ms);
return RT_EOK;
}
static rt_err_t governor_ondemand_set_frequency(struct rt_dvfs_scaling *dvfs, rt_ubase_t *out_freq)
{
if (!dvfs || !out_freq)
{
return -RT_EINVAL;
}
/* Ondemand sets frequency based on load, not requested frequency */
/* Return current frequency */
*out_freq = dvfs->cur_freq;
return RT_EOK;
}
static struct rt_dvfs_governor governor_ondemand =
{
.name = "ondemand",
.type = RT_DVFS_GOVERNOR_TYPE_ONDEMAND,
.start = governor_ondemand_start,
.stop = governor_ondemand_stop,
.suspend = governor_ondemand_suspend,
.resume = governor_ondemand_resume,
.set_interval = governor_ondemand_set_interval,
.set_frequency = governor_ondemand_set_frequency,
};
static int governor_ondemand_init(void)
{
rt_dvfs_governor_register(&governor_ondemand);
return 0;
}
INIT_CORE_EXPORT(governor_ondemand_init);
|
