drivers/gpu/drm/msm/msm_gpu_devfreq.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * Copyright (C) 2013 Red Hat
   4  * Author: Rob Clark <[email protected]>
   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 #include <linux/units.h>
  13
  14 /*
  15  * Power Management:
  16  */
  17
  18 static int msm_devfreq_target(struct device *dev, unsigned long *freq,
  19                 u32 flags)
  20 {
  21         struct msm_gpu *gpu = dev_to_gpu(dev);
  22         struct dev_pm_opp *opp;
  23
  24         /*
  25          * Note that devfreq_recommended_opp() can modify the freq
  26          * to something that actually is in the opp table:
  27          */
  28         opp = devfreq_recommended_opp(dev, freq, flags);
  29         if (IS_ERR(opp))
  30                 return PTR_ERR(opp);
  31
  32         trace_msm_gpu_freq_change(dev_pm_opp_get_freq(opp));
  33
  34         if (gpu->funcs->gpu_set_freq)
  35                 gpu->funcs->gpu_set_freq(gpu, opp);
  36         else
  37                 clk_set_rate(gpu->core_clk, *freq);
  38
  39         dev_pm_opp_put(opp);
  40
  41         return 0;
  42 }
  43
  44 static unsigned long get_freq(struct msm_gpu *gpu)
  45 {
  46         if (gpu->funcs->gpu_get_freq)
  47                 return gpu->funcs->gpu_get_freq(gpu);
  48
  49         return clk_get_rate(gpu->core_clk);
  50 }
  51
  52 static int msm_devfreq_get_dev_status(struct device *dev,
  53                 struct devfreq_dev_status *status)
  54 {
  55         struct msm_gpu *gpu = dev_to_gpu(dev);
  56         ktime_t time;
  57
  58         status->current_frequency = get_freq(gpu);
  59         status->busy_time = gpu->funcs->gpu_busy(gpu);
  60
  61         time = ktime_get();
  62         status->total_time = ktime_us_delta(time, gpu->devfreq.time);
  63         gpu->devfreq.time = time;
  64
  65         return 0;
  66 }
  67
  68 static int msm_devfreq_get_cur_freq(struct device *dev, unsigned long *freq)
  69 {
  70         *freq = get_freq(dev_to_gpu(dev));
  71
  72         return 0;
  73 }
  74
  75 static struct devfreq_dev_profile msm_devfreq_profile = {
  76         .timer = DEVFREQ_TIMER_DELAYED,
  77         .polling_ms = 50,
  78         .target = msm_devfreq_target,
  79         .get_dev_status = msm_devfreq_get_dev_status,
  80         .get_cur_freq = msm_devfreq_get_cur_freq,
  81 };
  82
  83 static void msm_devfreq_boost_work(struct kthread_work *work);
  84 static void msm_devfreq_idle_work(struct kthread_work *work);
  85
  86 void msm_devfreq_init(struct msm_gpu *gpu)
  87 {
  88         struct msm_gpu_devfreq *df = &gpu->devfreq;
  89
  90         /* We need target support to do devfreq */
  91         if (!gpu->funcs->gpu_busy)
  92                 return;
  93
  94         dev_pm_qos_add_request(&gpu->pdev->dev, &df->idle_freq,
  95                                DEV_PM_QOS_MAX_FREQUENCY,
  96                                PM_QOS_MAX_FREQUENCY_DEFAULT_VALUE);
  97         dev_pm_qos_add_request(&gpu->pdev->dev, &df->boost_freq,
  98                                DEV_PM_QOS_MIN_FREQUENCY, 0);
  99
 100         msm_devfreq_profile.initial_freq = gpu->fast_rate;
 101
 102         /*
 103          * Don't set the freq_table or max_state and let devfreq build the table
 104          * from OPP
 105          * After a deferred probe, these may have be left to non-zero values,
 106          * so set them back to zero before creating the devfreq device
 107          */
 108         msm_devfreq_profile.freq_table = NULL;
 109         msm_devfreq_profile.max_state = 0;
 110
 111         df->devfreq = devm_devfreq_add_device(&gpu->pdev->dev,
 112                         &msm_devfreq_profile, DEVFREQ_GOV_SIMPLE_ONDEMAND,
 113                         NULL);
 114
 115         if (IS_ERR(df->devfreq)) {
 116                 DRM_DEV_ERROR(&gpu->pdev->dev, "Couldn't initialize GPU devfreq\n");
 117                 df->devfreq = NULL;
 118                 return;
 119         }
 120
 121         devfreq_suspend_device(df->devfreq);
 122
 123         gpu->cooling = of_devfreq_cooling_register(gpu->pdev->dev.of_node, df->devfreq);
 124         if (IS_ERR(gpu->cooling)) {
 125                 DRM_DEV_ERROR(&gpu->pdev->dev,
 126                                 "Couldn't register GPU cooling device\n");
 127                 gpu->cooling = NULL;
 128         }
 129
 130         msm_hrtimer_work_init(&df->boost_work, gpu->worker, msm_devfreq_boost_work,
 131                               CLOCK_MONOTONIC, HRTIMER_MODE_REL);
 132         msm_hrtimer_work_init(&df->idle_work, gpu->worker, msm_devfreq_idle_work,
 133                               CLOCK_MONOTONIC, HRTIMER_MODE_REL);
 134 }
 135
 136 void msm_devfreq_cleanup(struct msm_gpu *gpu)
 137 {
 138         struct msm_gpu_devfreq *df = &gpu->devfreq;
 139
 140         devfreq_cooling_unregister(gpu->cooling);
 141         dev_pm_qos_remove_request(&df->boost_freq);
 142         dev_pm_qos_remove_request(&df->idle_freq);
 143 }
 144
 145 void msm_devfreq_resume(struct msm_gpu *gpu)
 146 {
 147         gpu->devfreq.busy_cycles = 0;
 148         gpu->devfreq.time = ktime_get();
 149
 150         devfreq_resume_device(gpu->devfreq.devfreq);
 151 }
 152
 153 void msm_devfreq_suspend(struct msm_gpu *gpu)
 154 {
 155         devfreq_suspend_device(gpu->devfreq.devfreq);
 156 }
 157
 158 static void msm_devfreq_boost_work(struct kthread_work *work)
 159 {
 160         struct msm_gpu_devfreq *df = container_of(work,
 161                         struct msm_gpu_devfreq, boost_work.work);
 162
 163         dev_pm_qos_update_request(&df->boost_freq, 0);
 164 }
 165
 166 void msm_devfreq_boost(struct msm_gpu *gpu, unsigned factor)
 167 {
 168         struct msm_gpu_devfreq *df = &gpu->devfreq;
 169         uint64_t freq;
 170
 171         freq = get_freq(gpu);
 172         freq *= factor;
 173
 174         /*
 175          * A nice little trap is that PM QoS operates in terms of KHz,
 176          * while devfreq operates in terms of Hz:
 177          */
 178         do_div(freq, HZ_PER_KHZ);
 179
 180         dev_pm_qos_update_request(&df->boost_freq, freq);
 181
 182         msm_hrtimer_queue_work(&df->boost_work,
 183                                ms_to_ktime(msm_devfreq_profile.polling_ms),
 184                                HRTIMER_MODE_REL);
 185 }
 186
 187 void msm_devfreq_active(struct msm_gpu *gpu)
 188 {
 189         struct msm_gpu_devfreq *df = &gpu->devfreq;
 190         struct devfreq_dev_status status;
 191         unsigned int idle_time;
 192
 193         if (!df->devfreq)
 194                 return;
 195
 196         /*
 197          * Cancel any pending transition to idle frequency:
 198          */
 199         hrtimer_cancel(&df->idle_work.timer);
 200
 201         idle_time = ktime_to_ms(ktime_sub(ktime_get(), df->idle_time));
 202
 203         /*
 204          * If we've been idle for a significant fraction of a polling
 205          * interval, then we won't meet the threshold of busyness for
 206          * the governor to ramp up the freq.. so give some boost
 207          */
 208         if (idle_time > msm_devfreq_profile.polling_ms) {
 209                 msm_devfreq_boost(gpu, 2);
 210         }
 211
 212         dev_pm_qos_update_request(&df->idle_freq,
 213                                   PM_QOS_MAX_FREQUENCY_DEFAULT_VALUE);
 214
 215         /*
 216          * Reset the polling interval so we aren't inconsistent
 217          * about freq vs busy/total cycles
 218          */
 219         msm_devfreq_get_dev_status(&gpu->pdev->dev, &status);
 220 }
 221
 222
 223 static void msm_devfreq_idle_work(struct kthread_work *work)
 224 {
 225         struct msm_gpu_devfreq *df = container_of(work,
 226                         struct msm_gpu_devfreq, idle_work.work);
 227         struct msm_gpu *gpu = container_of(df, struct msm_gpu, devfreq);
 228
 229         df->idle_time = ktime_get();
 230
 231         if (gpu->clamp_to_idle)
 232                 dev_pm_qos_update_request(&df->idle_freq, 0);
 233 }
 234
 235 void msm_devfreq_idle(struct msm_gpu *gpu)
 236 {
 237         struct msm_gpu_devfreq *df = &gpu->devfreq;
 238
 239         if (!df->devfreq)
 240                 return;
 241
 242         msm_hrtimer_queue_work(&df->idle_work, ms_to_ktime(1),
 243                                HRTIMER_MODE_REL);
 244 }