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Linux kernel mirror (for testing)
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linux
1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * Copyright (C) 2013 Red Hat
4 * Author: Rob Clark <robdclark@gmail.com>
5 */
6
7#include "msm_gpu.h"
8#include "msm_gpu_trace.h"
9
10#include <linux/devfreq.h>
11#include <linux/devfreq_cooling.h>
12
13/*
14 * Power Management:
15 */
16
17static int msm_devfreq_target(struct device *dev, unsigned long *freq,
18 u32 flags)
19{
20 struct msm_gpu *gpu = dev_to_gpu(dev);
21 struct dev_pm_opp *opp;
22
23 opp = devfreq_recommended_opp(dev, freq, flags);
24
25 /*
26 * If the GPU is idle, devfreq is not aware, so just ignore
27 * it's requests
28 */
29 if (gpu->devfreq.idle_freq) {
30 gpu->devfreq.idle_freq = *freq;
31 return 0;
32 }
33
34 if (IS_ERR(opp))
35 return PTR_ERR(opp);
36
37 trace_msm_gpu_freq_change(dev_pm_opp_get_freq(opp));
38
39 if (gpu->funcs->gpu_set_freq)
40 gpu->funcs->gpu_set_freq(gpu, opp);
41 else
42 clk_set_rate(gpu->core_clk, *freq);
43
44 dev_pm_opp_put(opp);
45
46 return 0;
47}
48
49static unsigned long get_freq(struct msm_gpu *gpu)
50{
51 if (gpu->devfreq.idle_freq)
52 return gpu->devfreq.idle_freq;
53
54 if (gpu->funcs->gpu_get_freq)
55 return gpu->funcs->gpu_get_freq(gpu);
56
57 return clk_get_rate(gpu->core_clk);
58}
59
60static int msm_devfreq_get_dev_status(struct device *dev,
61 struct devfreq_dev_status *status)
62{
63 struct msm_gpu *gpu = dev_to_gpu(dev);
64 ktime_t time;
65
66 status->current_frequency = get_freq(gpu);
67 status->busy_time = gpu->funcs->gpu_busy(gpu);
68
69 time = ktime_get();
70 status->total_time = ktime_us_delta(time, gpu->devfreq.time);
71 gpu->devfreq.time = time;
72
73 return 0;
74}
75
76static int msm_devfreq_get_cur_freq(struct device *dev, unsigned long *freq)
77{
78 *freq = get_freq(dev_to_gpu(dev));
79
80 return 0;
81}
82
83static struct devfreq_dev_profile msm_devfreq_profile = {
84 .timer = DEVFREQ_TIMER_DELAYED,
85 .polling_ms = 50,
86 .target = msm_devfreq_target,
87 .get_dev_status = msm_devfreq_get_dev_status,
88 .get_cur_freq = msm_devfreq_get_cur_freq,
89};
90
91void msm_devfreq_init(struct msm_gpu *gpu)
92{
93 /* We need target support to do devfreq */
94 if (!gpu->funcs->gpu_busy)
95 return;
96
97 msm_devfreq_profile.initial_freq = gpu->fast_rate;
98
99 /*
100 * Don't set the freq_table or max_state and let devfreq build the table
101 * from OPP
102 * After a deferred probe, these may have be left to non-zero values,
103 * so set them back to zero before creating the devfreq device
104 */
105 msm_devfreq_profile.freq_table = NULL;
106 msm_devfreq_profile.max_state = 0;
107
108 gpu->devfreq.devfreq = devm_devfreq_add_device(&gpu->pdev->dev,
109 &msm_devfreq_profile, DEVFREQ_GOV_SIMPLE_ONDEMAND,
110 NULL);
111
112 if (IS_ERR(gpu->devfreq.devfreq)) {
113 DRM_DEV_ERROR(&gpu->pdev->dev, "Couldn't initialize GPU devfreq\n");
114 gpu->devfreq.devfreq = NULL;
115 return;
116 }
117
118 devfreq_suspend_device(gpu->devfreq.devfreq);
119
120 gpu->cooling = of_devfreq_cooling_register(gpu->pdev->dev.of_node,
121 gpu->devfreq.devfreq);
122 if (IS_ERR(gpu->cooling)) {
123 DRM_DEV_ERROR(&gpu->pdev->dev,
124 "Couldn't register GPU cooling device\n");
125 gpu->cooling = NULL;
126 }
127}
128
129void msm_devfreq_cleanup(struct msm_gpu *gpu)
130{
131 devfreq_cooling_unregister(gpu->cooling);
132}
133
134void msm_devfreq_resume(struct msm_gpu *gpu)
135{
136 gpu->devfreq.busy_cycles = 0;
137 gpu->devfreq.time = ktime_get();
138
139 devfreq_resume_device(gpu->devfreq.devfreq);
140}
141
142void msm_devfreq_suspend(struct msm_gpu *gpu)
143{
144 devfreq_suspend_device(gpu->devfreq.devfreq);
145}
146
147void msm_devfreq_active(struct msm_gpu *gpu)
148{
149 struct msm_gpu_devfreq *df = &gpu->devfreq;
150 struct devfreq_dev_status status;
151 unsigned int idle_time;
152 unsigned long target_freq = df->idle_freq;
153
154 /*
155 * Hold devfreq lock to synchronize with get_dev_status()/
156 * target() callbacks
157 */
158 mutex_lock(&df->devfreq->lock);
159
160 idle_time = ktime_to_ms(ktime_sub(ktime_get(), df->idle_time));
161
162 /*
163 * If we've been idle for a significant fraction of a polling
164 * interval, then we won't meet the threshold of busyness for
165 * the governor to ramp up the freq.. so give some boost
166 */
167 if (idle_time > msm_devfreq_profile.polling_ms/2) {
168 target_freq *= 2;
169 }
170
171 df->idle_freq = 0;
172
173 msm_devfreq_target(&gpu->pdev->dev, &target_freq, 0);
174
175 /*
176 * Reset the polling interval so we aren't inconsistent
177 * about freq vs busy/total cycles
178 */
179 msm_devfreq_get_dev_status(&gpu->pdev->dev, &status);
180
181 mutex_unlock(&df->devfreq->lock);
182}
183
184void msm_devfreq_idle(struct msm_gpu *gpu)
185{
186 struct msm_gpu_devfreq *df = &gpu->devfreq;
187 unsigned long idle_freq, target_freq = 0;
188
189 /*
190 * Hold devfreq lock to synchronize with get_dev_status()/
191 * target() callbacks
192 */
193 mutex_lock(&df->devfreq->lock);
194
195 idle_freq = get_freq(gpu);
196
197 msm_devfreq_target(&gpu->pdev->dev, &target_freq, 0);
198
199 df->idle_time = ktime_get();
200 df->idle_freq = idle_freq;
201
202 mutex_unlock(&df->devfreq->lock);
203}