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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
4#include <linux/clk.h>
5#include <linux/devfreq.h>
6#include <linux/devfreq_cooling.h>
7#include <linux/platform_device.h>
8#include <linux/pm_opp.h>
9
10#include "panfrost_device.h"
11#include "panfrost_devfreq.h"
12
13static void panfrost_devfreq_update_utilization(struct panfrost_devfreq *pfdevfreq)
14{
15 ktime_t now, last;
16
17 now = ktime_get();
18 last = pfdevfreq->time_last_update;
19
20 if (pfdevfreq->busy_count > 0)
21 pfdevfreq->busy_time += ktime_sub(now, last);
22 else
23 pfdevfreq->idle_time += ktime_sub(now, last);
24
25 pfdevfreq->time_last_update = now;
26}
27
28static int panfrost_devfreq_target(struct device *dev, unsigned long *freq,
29 u32 flags)
30{
31 struct dev_pm_opp *opp;
32
33 opp = devfreq_recommended_opp(dev, freq, flags);
34 if (IS_ERR(opp))
35 return PTR_ERR(opp);
36 dev_pm_opp_put(opp);
37
38 return dev_pm_opp_set_rate(dev, *freq);
39}
40
41static void panfrost_devfreq_reset(struct panfrost_devfreq *pfdevfreq)
42{
43 pfdevfreq->busy_time = 0;
44 pfdevfreq->idle_time = 0;
45 pfdevfreq->time_last_update = ktime_get();
46}
47
48static int panfrost_devfreq_get_dev_status(struct device *dev,
49 struct devfreq_dev_status *status)
50{
51 struct panfrost_device *pfdev = dev_get_drvdata(dev);
52 struct panfrost_devfreq *pfdevfreq = &pfdev->pfdevfreq;
53 unsigned long irqflags;
54
55 status->current_frequency = clk_get_rate(pfdev->clock);
56
57 spin_lock_irqsave(&pfdevfreq->lock, irqflags);
58
59 panfrost_devfreq_update_utilization(pfdevfreq);
60
61 status->total_time = ktime_to_ns(ktime_add(pfdevfreq->busy_time,
62 pfdevfreq->idle_time));
63
64 status->busy_time = ktime_to_ns(pfdevfreq->busy_time);
65
66 panfrost_devfreq_reset(pfdevfreq);
67
68 spin_unlock_irqrestore(&pfdevfreq->lock, irqflags);
69
70 dev_dbg(pfdev->dev, "busy %lu total %lu %lu %% freq %lu MHz\n",
71 status->busy_time, status->total_time,
72 status->busy_time / (status->total_time / 100),
73 status->current_frequency / 1000 / 1000);
74
75 return 0;
76}
77
78static struct devfreq_dev_profile panfrost_devfreq_profile = {
79 .timer = DEVFREQ_TIMER_DELAYED,
80 .polling_ms = 50, /* ~3 frames */
81 .target = panfrost_devfreq_target,
82 .get_dev_status = panfrost_devfreq_get_dev_status,
83};
84
85int panfrost_devfreq_init(struct panfrost_device *pfdev)
86{
87 int ret;
88 struct dev_pm_opp *opp;
89 unsigned long cur_freq;
90 struct device *dev = &pfdev->pdev->dev;
91 struct devfreq *devfreq;
92 struct thermal_cooling_device *cooling;
93 struct panfrost_devfreq *pfdevfreq = &pfdev->pfdevfreq;
94
95 if (pfdev->comp->num_supplies > 1) {
96 /*
97 * GPUs with more than 1 supply require platform-specific handling:
98 * continue without devfreq
99 */
100 DRM_DEV_INFO(dev, "More than 1 supply is not supported yet\n");
101 return 0;
102 }
103
104 ret = devm_pm_opp_set_regulators(dev, pfdev->comp->supply_names);
105 if (ret) {
106 /* Continue if the optional regulator is missing */
107 if (ret != -ENODEV) {
108 if (ret != -EPROBE_DEFER)
109 DRM_DEV_ERROR(dev, "Couldn't set OPP regulators\n");
110 return ret;
111 }
112 }
113
114 ret = devm_pm_opp_of_add_table(dev);
115 if (ret) {
116 /* Optional, continue without devfreq */
117 if (ret == -ENODEV)
118 ret = 0;
119 return ret;
120 }
121 pfdevfreq->opp_of_table_added = true;
122
123 spin_lock_init(&pfdevfreq->lock);
124
125 panfrost_devfreq_reset(pfdevfreq);
126
127 cur_freq = clk_get_rate(pfdev->clock);
128
129 opp = devfreq_recommended_opp(dev, &cur_freq, 0);
130 if (IS_ERR(opp))
131 return PTR_ERR(opp);
132
133 panfrost_devfreq_profile.initial_freq = cur_freq;
134
135 /*
136 * Set the recommend OPP this will enable and configure the regulator
137 * if any and will avoid a switch off by regulator_late_cleanup()
138 */
139 ret = dev_pm_opp_set_opp(dev, opp);
140 if (ret) {
141 DRM_DEV_ERROR(dev, "Couldn't set recommended OPP\n");
142 return ret;
143 }
144
145 dev_pm_opp_put(opp);
146
147 /*
148 * Setup default thresholds for the simple_ondemand governor.
149 * The values are chosen based on experiments.
150 */
151 pfdevfreq->gov_data.upthreshold = 45;
152 pfdevfreq->gov_data.downdifferential = 5;
153
154 devfreq = devm_devfreq_add_device(dev, &panfrost_devfreq_profile,
155 DEVFREQ_GOV_SIMPLE_ONDEMAND,
156 &pfdevfreq->gov_data);
157 if (IS_ERR(devfreq)) {
158 DRM_DEV_ERROR(dev, "Couldn't initialize GPU devfreq\n");
159 return PTR_ERR(devfreq);
160 }
161 pfdevfreq->devfreq = devfreq;
162
163 cooling = devfreq_cooling_em_register(devfreq, NULL);
164 if (IS_ERR(cooling))
165 DRM_DEV_INFO(dev, "Failed to register cooling device\n");
166 else
167 pfdevfreq->cooling = cooling;
168
169 return 0;
170}
171
172void panfrost_devfreq_fini(struct panfrost_device *pfdev)
173{
174 struct panfrost_devfreq *pfdevfreq = &pfdev->pfdevfreq;
175
176 if (pfdevfreq->cooling) {
177 devfreq_cooling_unregister(pfdevfreq->cooling);
178 pfdevfreq->cooling = NULL;
179 }
180}
181
182void panfrost_devfreq_resume(struct panfrost_device *pfdev)
183{
184 struct panfrost_devfreq *pfdevfreq = &pfdev->pfdevfreq;
185
186 if (!pfdevfreq->devfreq)
187 return;
188
189 panfrost_devfreq_reset(pfdevfreq);
190
191 devfreq_resume_device(pfdevfreq->devfreq);
192}
193
194void panfrost_devfreq_suspend(struct panfrost_device *pfdev)
195{
196 struct panfrost_devfreq *pfdevfreq = &pfdev->pfdevfreq;
197
198 if (!pfdevfreq->devfreq)
199 return;
200
201 devfreq_suspend_device(pfdevfreq->devfreq);
202}
203
204void panfrost_devfreq_record_busy(struct panfrost_devfreq *pfdevfreq)
205{
206 unsigned long irqflags;
207
208 if (!pfdevfreq->devfreq)
209 return;
210
211 spin_lock_irqsave(&pfdevfreq->lock, irqflags);
212
213 panfrost_devfreq_update_utilization(pfdevfreq);
214
215 pfdevfreq->busy_count++;
216
217 spin_unlock_irqrestore(&pfdevfreq->lock, irqflags);
218}
219
220void panfrost_devfreq_record_idle(struct panfrost_devfreq *pfdevfreq)
221{
222 unsigned long irqflags;
223
224 if (!pfdevfreq->devfreq)
225 return;
226
227 spin_lock_irqsave(&pfdevfreq->lock, irqflags);
228
229 panfrost_devfreq_update_utilization(pfdevfreq);
230
231 WARN_ON(--pfdevfreq->busy_count < 0);
232
233 spin_unlock_irqrestore(&pfdevfreq->lock, irqflags);
234}