drivers/gpu/drm/lima/lima_devfreq.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * Copyright 2020 Martin Blumenstingl <[email protected]>
   4  *
   5  * Based on panfrost_devfreq.c:
   6  *   Copyright 2019 Collabora ltd.
   7  */
   8 #include <linux/clk.h>
   9 #include <linux/devfreq.h>
  10 #include <linux/devfreq_cooling.h>
  11 #include <linux/device.h>
  12 #include <linux/platform_device.h>
  13 #include <linux/pm_opp.h>
  14 #include <linux/property.h>
  15
  16 #include "lima_device.h"
  17 #include "lima_devfreq.h"
  18
  19 static void lima_devfreq_update_utilization(struct lima_devfreq *devfreq)
  20 {
  21         ktime_t now, last;
  22
  23         now = ktime_get();
  24         last = devfreq->time_last_update;
  25
  26         if (devfreq->busy_count > 0)
  27                 devfreq->busy_time += ktime_sub(now, last);
  28         else
  29                 devfreq->idle_time += ktime_sub(now, last);
  30
  31         devfreq->time_last_update = now;
  32 }
  33
  34 static int lima_devfreq_target(struct device *dev, unsigned long *freq,
  35                                u32 flags)
  36 {
  37         struct dev_pm_opp *opp;
  38         int err;
  39
  40         opp = devfreq_recommended_opp(dev, freq, flags);
  41         if (IS_ERR(opp))
  42                 return PTR_ERR(opp);
  43         dev_pm_opp_put(opp);
  44
  45         err = dev_pm_opp_set_rate(dev, *freq);
  46         if (err)
  47                 return err;
  48
  49         return 0;
  50 }
  51
  52 static void lima_devfreq_reset(struct lima_devfreq *devfreq)
  53 {
  54         devfreq->busy_time = 0;
  55         devfreq->idle_time = 0;
  56         devfreq->time_last_update = ktime_get();
  57 }
  58
  59 static int lima_devfreq_get_dev_status(struct device *dev,
  60                                        struct devfreq_dev_status *status)
  61 {
  62         struct lima_device *ldev = dev_get_drvdata(dev);
  63         struct lima_devfreq *devfreq = &ldev->devfreq;
  64         unsigned long irqflags;
  65
  66         status->current_frequency = clk_get_rate(ldev->clk_gpu);
  67
  68         spin_lock_irqsave(&devfreq->lock, irqflags);
  69
  70         lima_devfreq_update_utilization(devfreq);
  71
  72         status->total_time = ktime_to_ns(ktime_add(devfreq->busy_time,
  73                                                    devfreq->idle_time));
  74         status->busy_time = ktime_to_ns(devfreq->busy_time);
  75
  76         lima_devfreq_reset(devfreq);
  77
  78         spin_unlock_irqrestore(&devfreq->lock, irqflags);
  79
  80         dev_dbg(ldev->dev, "busy %lu total %lu %lu %% freq %lu MHz\n",
  81                 status->busy_time, status->total_time,
  82                 status->busy_time / (status->total_time / 100),
  83                 status->current_frequency / 1000 / 1000);
  84
  85         return 0;
  86 }
  87
  88 static struct devfreq_dev_profile lima_devfreq_profile = {
  89         .polling_ms = 50, /* ~3 frames */
  90         .target = lima_devfreq_target,
  91         .get_dev_status = lima_devfreq_get_dev_status,
  92 };
  93
  94 void lima_devfreq_fini(struct lima_device *ldev)
  95 {
  96         struct lima_devfreq *devfreq = &ldev->devfreq;
  97
  98         if (devfreq->cooling) {
  99                 devfreq_cooling_unregister(devfreq->cooling);
 100                 devfreq->cooling = NULL;
 101         }
 102
 103         if (devfreq->devfreq) {
 104                 devm_devfreq_remove_device(ldev->dev, devfreq->devfreq);
 105                 devfreq->devfreq = NULL;
 106         }
 107
 108         if (devfreq->opp_of_table_added) {
 109                 dev_pm_opp_of_remove_table(ldev->dev);
 110                 devfreq->opp_of_table_added = false;
 111         }
 112
 113         dev_pm_opp_put_regulators(devfreq->regulators_opp_table);
 114         dev_pm_opp_put_clkname(devfreq->clkname_opp_table);
 115         devfreq->regulators_opp_table = NULL;
 116         devfreq->clkname_opp_table = NULL;
 117 }
 118
 119 int lima_devfreq_init(struct lima_device *ldev)
 120 {
 121         struct thermal_cooling_device *cooling;
 122         struct device *dev = ldev->dev;
 123         struct opp_table *opp_table;
 124         struct devfreq *devfreq;
 125         struct lima_devfreq *ldevfreq = &ldev->devfreq;
 126         struct dev_pm_opp *opp;
 127         unsigned long cur_freq;
 128         int ret;
 129
 130         if (!device_property_present(dev, "operating-points-v2"))
 131                 /* Optional, continue without devfreq */
 132                 return 0;
 133
 134         spin_lock_init(&ldevfreq->lock);
 135
 136         opp_table = dev_pm_opp_set_clkname(dev, "core");
 137         if (IS_ERR(opp_table)) {
 138                 ret = PTR_ERR(opp_table);
 139                 goto err_fini;
 140         }
 141
 142         ldevfreq->clkname_opp_table = opp_table;
 143
 144         opp_table = dev_pm_opp_set_regulators(dev,
 145                                               (const char *[]){ "mali" },
 146                                               1);
 147         if (IS_ERR(opp_table)) {
 148                 ret = PTR_ERR(opp_table);
 149
 150                 /* Continue if the optional regulator is missing */
 151                 if (ret != -ENODEV)
 152                         goto err_fini;
 153         } else {
 154                 ldevfreq->regulators_opp_table = opp_table;
 155         }
 156
 157         ret = dev_pm_opp_of_add_table(dev);
 158         if (ret)
 159                 goto err_fini;
 160         ldevfreq->opp_of_table_added = true;
 161
 162         lima_devfreq_reset(ldevfreq);
 163
 164         cur_freq = clk_get_rate(ldev->clk_gpu);
 165
 166         opp = devfreq_recommended_opp(dev, &cur_freq, 0);
 167         if (IS_ERR(opp)) {
 168                 ret = PTR_ERR(opp);
 169                 goto err_fini;
 170         }
 171
 172         lima_devfreq_profile.initial_freq = cur_freq;
 173         dev_pm_opp_put(opp);
 174
 175         devfreq = devm_devfreq_add_device(dev, &lima_devfreq_profile,
 176                                           DEVFREQ_GOV_SIMPLE_ONDEMAND, NULL);
 177         if (IS_ERR(devfreq)) {
 178                 dev_err(dev, "Couldn't initialize GPU devfreq\n");
 179                 ret = PTR_ERR(devfreq);
 180                 goto err_fini;
 181         }
 182
 183         ldevfreq->devfreq = devfreq;
 184
 185         cooling = of_devfreq_cooling_register(dev->of_node, devfreq);
 186         if (IS_ERR(cooling))
 187                 dev_info(dev, "Failed to register cooling device\n");
 188         else
 189                 ldevfreq->cooling = cooling;
 190
 191         return 0;
 192
 193 err_fini:
 194         lima_devfreq_fini(ldev);
 195         return ret;
 196 }
 197
 198 void lima_devfreq_record_busy(struct lima_devfreq *devfreq)
 199 {
 200         unsigned long irqflags;
 201
 202         if (!devfreq->devfreq)
 203                 return;
 204
 205         spin_lock_irqsave(&devfreq->lock, irqflags);
 206
 207         lima_devfreq_update_utilization(devfreq);
 208
 209         devfreq->busy_count++;
 210
 211         spin_unlock_irqrestore(&devfreq->lock, irqflags);
 212 }
 213
 214 void lima_devfreq_record_idle(struct lima_devfreq *devfreq)
 215 {
 216         unsigned long irqflags;
 217
 218         if (!devfreq->devfreq)
 219                 return;
 220
 221         spin_lock_irqsave(&devfreq->lock, irqflags);
 222
 223         lima_devfreq_update_utilization(devfreq);
 224
 225         WARN_ON(--devfreq->busy_count < 0);
 226
 227         spin_unlock_irqrestore(&devfreq->lock, irqflags);
 228 }
 229
 230 int lima_devfreq_resume(struct lima_devfreq *devfreq)
 231 {
 232         unsigned long irqflags;
 233
 234         if (!devfreq->devfreq)
 235                 return 0;
 236
 237         spin_lock_irqsave(&devfreq->lock, irqflags);
 238
 239         lima_devfreq_reset(devfreq);
 240
 241         spin_unlock_irqrestore(&devfreq->lock, irqflags);
 242
 243         return devfreq_resume_device(devfreq->devfreq);
 244 }
 245
 246 int lima_devfreq_suspend(struct lima_devfreq *devfreq)
 247 {
 248         if (!devfreq->devfreq)
 249                 return 0;
 250
 251         return devfreq_suspend_device(devfreq->devfreq);
 252 }