summaryrefslogtreecommitdiff
path: root/drivers/gpu/drm/panfrost/panfrost_devfreq.c
blob: 413987038fbfccb954ccef97fc884bbc9f95298e (plain)
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
// SPDX-License-Identifier: GPL-2.0
/* Copyright 2019 Collabora ltd. */
#include <linux/devfreq.h>
#include <linux/devfreq_cooling.h>
#include <linux/platform_device.h>
#include <linux/pm_opp.h>
#include <linux/clk.h>
#include <linux/regulator/consumer.h>

#include "panfrost_device.h"
#include "panfrost_devfreq.h"
#include "panfrost_features.h"
#include "panfrost_issues.h"
#include "panfrost_gpu.h"
#include "panfrost_regs.h"

static void panfrost_devfreq_update_utilization(struct panfrost_device *pfdev);

static int panfrost_devfreq_target(struct device *dev, unsigned long *freq,
				   u32 flags)
{
	struct dev_pm_opp *opp;
	int err;

	opp = devfreq_recommended_opp(dev, freq, flags);
	if (IS_ERR(opp))
		return PTR_ERR(opp);
	dev_pm_opp_put(opp);

	err = dev_pm_opp_set_rate(dev, *freq);
	if (err)
		return err;

	return 0;
}

static void panfrost_devfreq_reset(struct panfrost_device *pfdev)
{
	pfdev->devfreq.busy_time = 0;
	pfdev->devfreq.idle_time = 0;
	pfdev->devfreq.time_last_update = ktime_get();
}

static int panfrost_devfreq_get_dev_status(struct device *dev,
					   struct devfreq_dev_status *status)
{
	struct panfrost_device *pfdev = dev_get_drvdata(dev);

	panfrost_devfreq_update_utilization(pfdev);

	status->current_frequency = clk_get_rate(pfdev->clock);
	status->total_time = ktime_to_ns(ktime_add(pfdev->devfreq.busy_time,
						   pfdev->devfreq.idle_time));

	status->busy_time = ktime_to_ns(pfdev->devfreq.busy_time);

	panfrost_devfreq_reset(pfdev);

	dev_dbg(pfdev->dev, "busy %lu total %lu %lu %% freq %lu MHz\n", status->busy_time,
		status->total_time,
		status->busy_time / (status->total_time / 100),
		status->current_frequency / 1000 / 1000);

	return 0;
}

static struct devfreq_dev_profile panfrost_devfreq_profile = {
	.polling_ms = 50, /* ~3 frames */
	.target = panfrost_devfreq_target,
	.get_dev_status = panfrost_devfreq_get_dev_status,
};

int panfrost_devfreq_init(struct panfrost_device *pfdev)
{
	int ret;
	struct dev_pm_opp *opp;
	unsigned long cur_freq;
	struct device *dev = &pfdev->pdev->dev;
	struct devfreq *devfreq;
	struct thermal_cooling_device *cooling;

	ret = dev_pm_opp_of_add_table(dev);
	if (ret == -ENODEV) /* Optional, continue without devfreq */
		return 0;
	else if (ret)
		return ret;

	panfrost_devfreq_reset(pfdev);

	cur_freq = clk_get_rate(pfdev->clock);

	opp = devfreq_recommended_opp(dev, &cur_freq, 0);
	if (IS_ERR(opp))
		return PTR_ERR(opp);

	panfrost_devfreq_profile.initial_freq = cur_freq;
	dev_pm_opp_put(opp);

	devfreq = devm_devfreq_add_device(dev, &panfrost_devfreq_profile,
					  DEVFREQ_GOV_SIMPLE_ONDEMAND, NULL);
	if (IS_ERR(devfreq)) {
		DRM_DEV_ERROR(dev, "Couldn't initialize GPU devfreq\n");
		dev_pm_opp_of_remove_table(dev);
		return PTR_ERR(devfreq);
	}
	pfdev->devfreq.devfreq = devfreq;

	cooling = of_devfreq_cooling_register(dev->of_node, devfreq);
	if (IS_ERR(cooling))
		DRM_DEV_INFO(dev, "Failed to register cooling device\n");
	else
		pfdev->devfreq.cooling = cooling;

	return 0;
}

void panfrost_devfreq_fini(struct panfrost_device *pfdev)
{
	if (pfdev->devfreq.cooling)
		devfreq_cooling_unregister(pfdev->devfreq.cooling);
	dev_pm_opp_of_remove_table(&pfdev->pdev->dev);
}

void panfrost_devfreq_resume(struct panfrost_device *pfdev)
{
	if (!pfdev->devfreq.devfreq)
		return;

	panfrost_devfreq_reset(pfdev);

	devfreq_resume_device(pfdev->devfreq.devfreq);
}

void panfrost_devfreq_suspend(struct panfrost_device *pfdev)
{
	if (!pfdev->devfreq.devfreq)
		return;

	devfreq_suspend_device(pfdev->devfreq.devfreq);
}

static void panfrost_devfreq_update_utilization(struct panfrost_device *pfdev)
{
	ktime_t now;
	ktime_t last;

	if (!pfdev->devfreq.devfreq)
		return;

	now = ktime_get();
	last = pfdev->devfreq.time_last_update;

	if (atomic_read(&pfdev->devfreq.busy_count) > 0)
		pfdev->devfreq.busy_time += ktime_sub(now, last);
	else
		pfdev->devfreq.idle_time += ktime_sub(now, last);

	pfdev->devfreq.time_last_update = now;
}

void panfrost_devfreq_record_busy(struct panfrost_device *pfdev)
{
	panfrost_devfreq_update_utilization(pfdev);
	atomic_inc(&pfdev->devfreq.busy_count);
}

void panfrost_devfreq_record_idle(struct panfrost_device *pfdev)
{
	int count;

	panfrost_devfreq_update_utilization(pfdev);
	count = atomic_dec_if_positive(&pfdev->devfreq.busy_count);
	WARN_ON(count < 0);
}