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1// SPDX-License-Identifier: GPL-2.0
2/* Copyright 2019 Collabora ltd. */
3#include <linux/devfreq.h>
4#include <linux/platform_device.h>
5#include <linux/pm_opp.h>
6#include <linux/clk.h>
7#include <linux/regulator/consumer.h>
8
9#include "panfrost_device.h"
10#include "panfrost_devfreq.h"
11#include "panfrost_features.h"
12#include "panfrost_issues.h"
13#include "panfrost_gpu.h"
14#include "panfrost_regs.h"
15
16static void panfrost_devfreq_update_utilization(struct panfrost_device *pfdev, int slot);
17
18static int panfrost_devfreq_target(struct device *dev, unsigned long *freq,
19 u32 flags)
20{
21 struct panfrost_device *pfdev = platform_get_drvdata(to_platform_device(dev));
22 struct dev_pm_opp *opp;
23 unsigned long old_clk_rate = pfdev->devfreq.cur_freq;
24 unsigned long target_volt, target_rate;
25 int err;
26
27 opp = devfreq_recommended_opp(dev, freq, flags);
28 if (IS_ERR(opp))
29 return PTR_ERR(opp);
30
31 target_rate = dev_pm_opp_get_freq(opp);
32 target_volt = dev_pm_opp_get_voltage(opp);
33 dev_pm_opp_put(opp);
34
35 if (old_clk_rate == target_rate)
36 return 0;
37
38 /*
39 * If frequency scaling from low to high, adjust voltage first.
40 * If frequency scaling from high to low, adjust frequency first.
41 */
42 if (old_clk_rate < target_rate) {
43 err = regulator_set_voltage(pfdev->regulator, target_volt,
44 target_volt);
45 if (err) {
46 dev_err(dev, "Cannot set voltage %lu uV\n",
47 target_volt);
48 return err;
49 }
50 }
51
52 err = clk_set_rate(pfdev->clock, target_rate);
53 if (err) {
54 dev_err(dev, "Cannot set frequency %lu (%d)\n", target_rate,
55 err);
56 regulator_set_voltage(pfdev->regulator, pfdev->devfreq.cur_volt,
57 pfdev->devfreq.cur_volt);
58 return err;
59 }
60
61 if (old_clk_rate > target_rate) {
62 err = regulator_set_voltage(pfdev->regulator, target_volt,
63 target_volt);
64 if (err)
65 dev_err(dev, "Cannot set voltage %lu uV\n", target_volt);
66 }
67
68 pfdev->devfreq.cur_freq = target_rate;
69 pfdev->devfreq.cur_volt = target_volt;
70
71 return 0;
72}
73
74static void panfrost_devfreq_reset(struct panfrost_device *pfdev)
75{
76 ktime_t now = ktime_get();
77 int i;
78
79 for (i = 0; i < NUM_JOB_SLOTS; i++) {
80 pfdev->devfreq.slot[i].busy_time = 0;
81 pfdev->devfreq.slot[i].idle_time = 0;
82 pfdev->devfreq.slot[i].time_last_update = now;
83 }
84}
85
86static int panfrost_devfreq_get_dev_status(struct device *dev,
87 struct devfreq_dev_status *status)
88{
89 struct panfrost_device *pfdev = platform_get_drvdata(to_platform_device(dev));
90 int i;
91
92 for (i = 0; i < NUM_JOB_SLOTS; i++) {
93 panfrost_devfreq_update_utilization(pfdev, i);
94 }
95
96 status->current_frequency = clk_get_rate(pfdev->clock);
97 status->total_time = ktime_to_ns(ktime_add(pfdev->devfreq.slot[0].busy_time,
98 pfdev->devfreq.slot[0].idle_time));
99
100 status->busy_time = 0;
101 for (i = 0; i < NUM_JOB_SLOTS; i++) {
102 status->busy_time += ktime_to_ns(pfdev->devfreq.slot[i].busy_time);
103 }
104
105 /* We're scheduling only to one core atm, so don't divide for now */
106 /* status->busy_time /= NUM_JOB_SLOTS; */
107
108 panfrost_devfreq_reset(pfdev);
109
110 dev_dbg(pfdev->dev, "busy %lu total %lu %lu %% freq %lu MHz\n", status->busy_time,
111 status->total_time,
112 status->busy_time / (status->total_time / 100),
113 status->current_frequency / 1000 / 1000);
114
115 return 0;
116}
117
118static int panfrost_devfreq_get_cur_freq(struct device *dev, unsigned long *freq)
119{
120 struct panfrost_device *pfdev = platform_get_drvdata(to_platform_device(dev));
121
122 *freq = pfdev->devfreq.cur_freq;
123
124 return 0;
125}
126
127static struct devfreq_dev_profile panfrost_devfreq_profile = {
128 .polling_ms = 50, /* ~3 frames */
129 .target = panfrost_devfreq_target,
130 .get_dev_status = panfrost_devfreq_get_dev_status,
131 .get_cur_freq = panfrost_devfreq_get_cur_freq,
132};
133
134int panfrost_devfreq_init(struct panfrost_device *pfdev)
135{
136 int ret;
137 struct dev_pm_opp *opp;
138
139 ret = dev_pm_opp_of_add_table(&pfdev->pdev->dev);
140 if (ret == -ENODEV) /* Optional, continue without devfreq */
141 return 0;
142 else if (ret)
143 return ret;
144
145 panfrost_devfreq_reset(pfdev);
146
147 pfdev->devfreq.cur_freq = clk_get_rate(pfdev->clock);
148
149 opp = devfreq_recommended_opp(&pfdev->pdev->dev, &pfdev->devfreq.cur_freq, 0);
150 if (IS_ERR(opp))
151 return PTR_ERR(opp);
152
153 panfrost_devfreq_profile.initial_freq = pfdev->devfreq.cur_freq;
154 dev_pm_opp_put(opp);
155
156 pfdev->devfreq.devfreq = devm_devfreq_add_device(&pfdev->pdev->dev,
157 &panfrost_devfreq_profile, DEVFREQ_GOV_SIMPLE_ONDEMAND,
158 NULL);
159 if (IS_ERR(pfdev->devfreq.devfreq)) {
160 DRM_DEV_ERROR(&pfdev->pdev->dev, "Couldn't initialize GPU devfreq\n");
161 ret = PTR_ERR(pfdev->devfreq.devfreq);
162 pfdev->devfreq.devfreq = NULL;
163 dev_pm_opp_of_remove_table(&pfdev->pdev->dev);
164 return ret;
165 }
166
167 return 0;
168}
169
170void panfrost_devfreq_fini(struct panfrost_device *pfdev)
171{
172 dev_pm_opp_of_remove_table(&pfdev->pdev->dev);
173}
174
175void panfrost_devfreq_resume(struct panfrost_device *pfdev)
176{
177 int i;
178
179 if (!pfdev->devfreq.devfreq)
180 return;
181
182 panfrost_devfreq_reset(pfdev);
183 for (i = 0; i < NUM_JOB_SLOTS; i++)
184 pfdev->devfreq.slot[i].busy = false;
185
186 devfreq_resume_device(pfdev->devfreq.devfreq);
187}
188
189void panfrost_devfreq_suspend(struct panfrost_device *pfdev)
190{
191 if (!pfdev->devfreq.devfreq)
192 return;
193
194 devfreq_suspend_device(pfdev->devfreq.devfreq);
195}
196
197static void panfrost_devfreq_update_utilization(struct panfrost_device *pfdev, int slot)
198{
199 struct panfrost_devfreq_slot *devfreq_slot = &pfdev->devfreq.slot[slot];
200 ktime_t now;
201 ktime_t last;
202
203 if (!pfdev->devfreq.devfreq)
204 return;
205
206 now = ktime_get();
207 last = pfdev->devfreq.slot[slot].time_last_update;
208
209 /* If we last recorded a transition to busy, we have been idle since */
210 if (devfreq_slot->busy)
211 pfdev->devfreq.slot[slot].busy_time += ktime_sub(now, last);
212 else
213 pfdev->devfreq.slot[slot].idle_time += ktime_sub(now, last);
214
215 pfdev->devfreq.slot[slot].time_last_update = now;
216}
217
218/* The job scheduler is expected to call this at every transition busy <-> idle */
219void panfrost_devfreq_record_transition(struct panfrost_device *pfdev, int slot)
220{
221 struct panfrost_devfreq_slot *devfreq_slot = &pfdev->devfreq.slot[slot];
222
223 panfrost_devfreq_update_utilization(pfdev, slot);
224 devfreq_slot->busy = !devfreq_slot->busy;
225}
1// SPDX-License-Identifier: GPL-2.0
2/* Copyright 2019 Collabora ltd. */
3#include <linux/devfreq.h>
4#include <linux/devfreq_cooling.h>
5#include <linux/platform_device.h>
6#include <linux/pm_opp.h>
7#include <linux/clk.h>
8#include <linux/regulator/consumer.h>
9
10#include "panfrost_device.h"
11#include "panfrost_devfreq.h"
12#include "panfrost_features.h"
13#include "panfrost_issues.h"
14#include "panfrost_gpu.h"
15#include "panfrost_regs.h"
16
17static void panfrost_devfreq_update_utilization(struct panfrost_device *pfdev);
18
19static int panfrost_devfreq_target(struct device *dev, unsigned long *freq,
20 u32 flags)
21{
22 struct dev_pm_opp *opp;
23 int err;
24
25 opp = devfreq_recommended_opp(dev, freq, flags);
26 if (IS_ERR(opp))
27 return PTR_ERR(opp);
28 dev_pm_opp_put(opp);
29
30 err = dev_pm_opp_set_rate(dev, *freq);
31 if (err)
32 return err;
33
34 return 0;
35}
36
37static void panfrost_devfreq_reset(struct panfrost_device *pfdev)
38{
39 pfdev->devfreq.busy_time = 0;
40 pfdev->devfreq.idle_time = 0;
41 pfdev->devfreq.time_last_update = ktime_get();
42}
43
44static int panfrost_devfreq_get_dev_status(struct device *dev,
45 struct devfreq_dev_status *status)
46{
47 struct panfrost_device *pfdev = dev_get_drvdata(dev);
48
49 panfrost_devfreq_update_utilization(pfdev);
50
51 status->current_frequency = clk_get_rate(pfdev->clock);
52 status->total_time = ktime_to_ns(ktime_add(pfdev->devfreq.busy_time,
53 pfdev->devfreq.idle_time));
54
55 status->busy_time = ktime_to_ns(pfdev->devfreq.busy_time);
56
57 panfrost_devfreq_reset(pfdev);
58
59 dev_dbg(pfdev->dev, "busy %lu total %lu %lu %% freq %lu MHz\n", status->busy_time,
60 status->total_time,
61 status->busy_time / (status->total_time / 100),
62 status->current_frequency / 1000 / 1000);
63
64 return 0;
65}
66
67static struct devfreq_dev_profile panfrost_devfreq_profile = {
68 .polling_ms = 50, /* ~3 frames */
69 .target = panfrost_devfreq_target,
70 .get_dev_status = panfrost_devfreq_get_dev_status,
71};
72
73int panfrost_devfreq_init(struct panfrost_device *pfdev)
74{
75 int ret;
76 struct dev_pm_opp *opp;
77 unsigned long cur_freq;
78 struct device *dev = &pfdev->pdev->dev;
79 struct devfreq *devfreq;
80 struct thermal_cooling_device *cooling;
81
82 ret = dev_pm_opp_of_add_table(dev);
83 if (ret == -ENODEV) /* Optional, continue without devfreq */
84 return 0;
85 else if (ret)
86 return ret;
87
88 panfrost_devfreq_reset(pfdev);
89
90 cur_freq = clk_get_rate(pfdev->clock);
91
92 opp = devfreq_recommended_opp(dev, &cur_freq, 0);
93 if (IS_ERR(opp))
94 return PTR_ERR(opp);
95
96 panfrost_devfreq_profile.initial_freq = cur_freq;
97 dev_pm_opp_put(opp);
98
99 devfreq = devm_devfreq_add_device(dev, &panfrost_devfreq_profile,
100 DEVFREQ_GOV_SIMPLE_ONDEMAND, NULL);
101 if (IS_ERR(devfreq)) {
102 DRM_DEV_ERROR(dev, "Couldn't initialize GPU devfreq\n");
103 dev_pm_opp_of_remove_table(dev);
104 return PTR_ERR(devfreq);
105 }
106 pfdev->devfreq.devfreq = devfreq;
107
108 cooling = of_devfreq_cooling_register(dev->of_node, devfreq);
109 if (IS_ERR(cooling))
110 DRM_DEV_INFO(dev, "Failed to register cooling device\n");
111 else
112 pfdev->devfreq.cooling = cooling;
113
114 return 0;
115}
116
117void panfrost_devfreq_fini(struct panfrost_device *pfdev)
118{
119 if (pfdev->devfreq.cooling)
120 devfreq_cooling_unregister(pfdev->devfreq.cooling);
121 dev_pm_opp_of_remove_table(&pfdev->pdev->dev);
122}
123
124void panfrost_devfreq_resume(struct panfrost_device *pfdev)
125{
126 if (!pfdev->devfreq.devfreq)
127 return;
128
129 panfrost_devfreq_reset(pfdev);
130
131 devfreq_resume_device(pfdev->devfreq.devfreq);
132}
133
134void panfrost_devfreq_suspend(struct panfrost_device *pfdev)
135{
136 if (!pfdev->devfreq.devfreq)
137 return;
138
139 devfreq_suspend_device(pfdev->devfreq.devfreq);
140}
141
142static void panfrost_devfreq_update_utilization(struct panfrost_device *pfdev)
143{
144 ktime_t now;
145 ktime_t last;
146
147 if (!pfdev->devfreq.devfreq)
148 return;
149
150 now = ktime_get();
151 last = pfdev->devfreq.time_last_update;
152
153 if (atomic_read(&pfdev->devfreq.busy_count) > 0)
154 pfdev->devfreq.busy_time += ktime_sub(now, last);
155 else
156 pfdev->devfreq.idle_time += ktime_sub(now, last);
157
158 pfdev->devfreq.time_last_update = now;
159}
160
161void panfrost_devfreq_record_busy(struct panfrost_device *pfdev)
162{
163 panfrost_devfreq_update_utilization(pfdev);
164 atomic_inc(&pfdev->devfreq.busy_count);
165}
166
167void panfrost_devfreq_record_idle(struct panfrost_device *pfdev)
168{
169 int count;
170
171 panfrost_devfreq_update_utilization(pfdev);
172 count = atomic_dec_if_positive(&pfdev->devfreq.busy_count);
173 WARN_ON(count < 0);
174}