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         dev_pm_opp_of_remove_table(ldev->dev);
 104
 105         if (devfreq->regulators_opp_table) {
 106                 dev_pm_opp_put_regulators(devfreq->regulators_opp_table);
 107                 devfreq->regulators_opp_table = NULL;
 108         }
 109
 110         if (devfreq->clkname_opp_table) {
 111                 dev_pm_opp_put_clkname(devfreq->clkname_opp_table);
 112                 devfreq->clkname_opp_table = NULL;
 113         }
 114 }
 115
 116 int lima_devfreq_init(struct lima_device *ldev)
 117 {
 118         struct thermal_cooling_device *cooling;
 119         struct device *dev = ldev->dev;
 120         struct opp_table *opp_table;
 121         struct devfreq *devfreq;
 122         struct lima_devfreq *ldevfreq = &ldev->devfreq;
 123         struct dev_pm_opp *opp;
 124         unsigned long cur_freq;
 125         int ret;
 126
 127         if (!device_property_present(dev, "operating-points-v2"))
 128                 /* Optional, continue without devfreq */
 129                 return 0;
 130
 131         spin_lock_init(&ldevfreq->lock);
 132
 133         opp_table = dev_pm_opp_set_clkname(dev, "core");
 134         if (IS_ERR(opp_table)) {
 135                 ret = PTR_ERR(opp_table);
 136                 goto err_fini;
 137         }
 138
 139         ldevfreq->clkname_opp_table = opp_table;
 140
 141         opp_table = dev_pm_opp_set_regulators(dev,
 142                                               (const char *[]){ "mali" },
 143                                               1);
 144         if (IS_ERR(opp_table)) {
 145                 ret = PTR_ERR(opp_table);
 146
 147                 /* Continue if the optional regulator is missing */
 148                 if (ret != -ENODEV)
 149                         goto err_fini;
 150         } else {
 151                 ldevfreq->regulators_opp_table = opp_table;
 152         }
 153
 154         ret = dev_pm_opp_of_add_table(dev);
 155         if (ret)
 156                 goto err_fini;
 157
 158         lima_devfreq_reset(ldevfreq);
 159
 160         cur_freq = clk_get_rate(ldev->clk_gpu);
 161
 162         opp = devfreq_recommended_opp(dev, &cur_freq, 0);
 163         if (IS_ERR(opp)) {
 164                 ret = PTR_ERR(opp);
 165                 goto err_fini;
 166         }
 167
 168         lima_devfreq_profile.initial_freq = cur_freq;
 169         dev_pm_opp_put(opp);
 170
 171         devfreq = devm_devfreq_add_device(dev, &lima_devfreq_profile,
 172                                           DEVFREQ_GOV_SIMPLE_ONDEMAND, NULL);
 173         if (IS_ERR(devfreq)) {
 174                 dev_err(dev, "Couldn't initialize GPU devfreq\n");
 175                 ret = PTR_ERR(devfreq);
 176                 goto err_fini;
 177         }
 178
 179         ldevfreq->devfreq = devfreq;
 180
 181         cooling = of_devfreq_cooling_register(dev->of_node, devfreq);
 182         if (IS_ERR(cooling))
 183                 dev_info(dev, "Failed to register cooling device\n");
 184         else
 185                 ldevfreq->cooling = cooling;
 186
 187         return 0;
 188
 189 err_fini:
 190         lima_devfreq_fini(ldev);
 191         return ret;
 192 }
 193
 194 void lima_devfreq_record_busy(struct lima_devfreq *devfreq)
 195 {
 196         unsigned long irqflags;
 197
 198         if (!devfreq->devfreq)
 199                 return;
 200
 201         spin_lock_irqsave(&devfreq->lock, irqflags);
 202
 203         lima_devfreq_update_utilization(devfreq);
 204
 205         devfreq->busy_count++;
 206
 207         spin_unlock_irqrestore(&devfreq->lock, irqflags);
 208 }
 209
 210 void lima_devfreq_record_idle(struct lima_devfreq *devfreq)
 211 {
 212         unsigned long irqflags;
 213
 214         if (!devfreq->devfreq)
 215                 return;
 216
 217         spin_lock_irqsave(&devfreq->lock, irqflags);
 218
 219         lima_devfreq_update_utilization(devfreq);
 220
 221         WARN_ON(--devfreq->busy_count < 0);
 222
 223         spin_unlock_irqrestore(&devfreq->lock, irqflags);
 224 }
 225
 226 int lima_devfreq_resume(struct lima_devfreq *devfreq)
 227 {
 228         unsigned long irqflags;
 229
 230         if (!devfreq->devfreq)
 231                 return 0;
 232
 233         spin_lock_irqsave(&devfreq->lock, irqflags);
 234
 235         lima_devfreq_reset(devfreq);
 236
 237         spin_unlock_irqrestore(&devfreq->lock, irqflags);
 238
 239         return devfreq_resume_device(devfreq->devfreq);
 240 }
 241
 242 int lima_devfreq_suspend(struct lima_devfreq *devfreq)
 243 {
 244         if (!devfreq->devfreq)
 245                 return 0;
 246
 247         return devfreq_suspend_device(devfreq->devfreq);
 248 }