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
  39         opp = devfreq_recommended_opp(dev, freq, flags);
  40         if (IS_ERR(opp))
  41                 return PTR_ERR(opp);
  42         dev_pm_opp_put(opp);
  43
  44         return dev_pm_opp_set_rate(dev, *freq);
  45 }
  46
  47 static void lima_devfreq_reset(struct lima_devfreq *devfreq)
  48 {
  49         devfreq->busy_time = 0;
  50         devfreq->idle_time = 0;
  51         devfreq->time_last_update = ktime_get();
  52 }
  53
  54 static int lima_devfreq_get_dev_status(struct device *dev,
  55                                        struct devfreq_dev_status *status)
  56 {
  57         struct lima_device *ldev = dev_get_drvdata(dev);
  58         struct lima_devfreq *devfreq = &ldev->devfreq;
  59         unsigned long irqflags;
  60
  61         status->current_frequency = clk_get_rate(ldev->clk_gpu);
  62
  63         spin_lock_irqsave(&devfreq->lock, irqflags);
  64
  65         lima_devfreq_update_utilization(devfreq);
  66
  67         status->total_time = ktime_to_ns(ktime_add(devfreq->busy_time,
  68                                                    devfreq->idle_time));
  69         status->busy_time = ktime_to_ns(devfreq->busy_time);
  70
  71         lima_devfreq_reset(devfreq);
  72
  73         spin_unlock_irqrestore(&devfreq->lock, irqflags);
  74
  75         dev_dbg(ldev->dev, "busy %lu total %lu %lu %% freq %lu MHz\n",
  76                 status->busy_time, status->total_time,
  77                 status->busy_time / (status->total_time / 100),
  78                 status->current_frequency / 1000 / 1000);
  79
  80         return 0;
  81 }
  82
  83 static struct devfreq_dev_profile lima_devfreq_profile = {
  84         .polling_ms = 50, /* ~3 frames */
  85         .target = lima_devfreq_target,
  86         .get_dev_status = lima_devfreq_get_dev_status,
  87 };
  88
  89 void lima_devfreq_fini(struct lima_device *ldev)
  90 {
  91         struct lima_devfreq *devfreq = &ldev->devfreq;
  92
  93         if (devfreq->cooling) {
  94                 devfreq_cooling_unregister(devfreq->cooling);
  95                 devfreq->cooling = NULL;
  96         }
  97
  98         if (devfreq->devfreq) {
  99                 devm_devfreq_remove_device(ldev->dev, devfreq->devfreq);
 100                 devfreq->devfreq = NULL;
 101         }
 102 }
 103
 104 int lima_devfreq_init(struct lima_device *ldev)
 105 {
 106         struct thermal_cooling_device *cooling;
 107         struct device *dev = ldev->dev;
 108         struct devfreq *devfreq;
 109         struct lima_devfreq *ldevfreq = &ldev->devfreq;
 110         struct dev_pm_opp *opp;
 111         unsigned long cur_freq;
 112         int ret;
 113
 114         if (!device_property_present(dev, "operating-points-v2"))
 115                 /* Optional, continue without devfreq */
 116                 return 0;
 117
 118         spin_lock_init(&ldevfreq->lock);
 119
 120         ret = devm_pm_opp_set_clkname(dev, "core");
 121         if (ret)
 122                 return ret;
 123
 124         ret = devm_pm_opp_set_regulators(dev, (const char *[]){ "mali" }, 1);
 125         if (ret) {
 126                 /* Continue if the optional regulator is missing */
 127                 if (ret != -ENODEV)
 128                         return ret;
 129         }
 130
 131         ret = devm_pm_opp_of_add_table(dev);
 132         if (ret)
 133                 return ret;
 134
 135         lima_devfreq_reset(ldevfreq);
 136
 137         cur_freq = clk_get_rate(ldev->clk_gpu);
 138
 139         opp = devfreq_recommended_opp(dev, &cur_freq, 0);
 140         if (IS_ERR(opp))
 141                 return PTR_ERR(opp);
 142
 143         lima_devfreq_profile.initial_freq = cur_freq;
 144         dev_pm_opp_put(opp);
 145
 146         devfreq = devm_devfreq_add_device(dev, &lima_devfreq_profile,
 147                                           DEVFREQ_GOV_SIMPLE_ONDEMAND, NULL);
 148         if (IS_ERR(devfreq)) {
 149                 dev_err(dev, "Couldn't initialize GPU devfreq\n");
 150                 return PTR_ERR(devfreq);
 151         }
 152
 153         ldevfreq->devfreq = devfreq;
 154
 155         cooling = of_devfreq_cooling_register(dev->of_node, devfreq);
 156         if (IS_ERR(cooling))
 157                 dev_info(dev, "Failed to register cooling device\n");
 158         else
 159                 ldevfreq->cooling = cooling;
 160
 161         return 0;
 162 }
 163
 164 void lima_devfreq_record_busy(struct lima_devfreq *devfreq)
 165 {
 166         unsigned long irqflags;
 167
 168         if (!devfreq->devfreq)
 169                 return;
 170
 171         spin_lock_irqsave(&devfreq->lock, irqflags);
 172
 173         lima_devfreq_update_utilization(devfreq);
 174
 175         devfreq->busy_count++;
 176
 177         spin_unlock_irqrestore(&devfreq->lock, irqflags);
 178 }
 179
 180 void lima_devfreq_record_idle(struct lima_devfreq *devfreq)
 181 {
 182         unsigned long irqflags;
 183
 184         if (!devfreq->devfreq)
 185                 return;
 186
 187         spin_lock_irqsave(&devfreq->lock, irqflags);
 188
 189         lima_devfreq_update_utilization(devfreq);
 190
 191         WARN_ON(--devfreq->busy_count < 0);
 192
 193         spin_unlock_irqrestore(&devfreq->lock, irqflags);
 194 }
 195
 196 int lima_devfreq_resume(struct lima_devfreq *devfreq)
 197 {
 198         unsigned long irqflags;
 199
 200         if (!devfreq->devfreq)
 201                 return 0;
 202
 203         spin_lock_irqsave(&devfreq->lock, irqflags);
 204
 205         lima_devfreq_reset(devfreq);
 206
 207         spin_unlock_irqrestore(&devfreq->lock, irqflags);
 208
 209         return devfreq_resume_device(devfreq->devfreq);
 210 }
 211
 212 int lima_devfreq_suspend(struct lima_devfreq *devfreq)
 213 {
 214         if (!devfreq->devfreq)
 215                 return 0;
 216
 217         return devfreq_suspend_device(devfreq->devfreq);
 218 }