// SPDX-License-Identifier: GPL-2.0 /* Copyright 2019 Collabora ltd. */ #include <linux/clk.h> #include <linux/devfreq.h> #include <linux/devfreq_cooling.h> #include <linux/platform_device.h> #include <linux/pm_opp.h> #include "panfrost_device.h" #include "panfrost_devfreq.h" static void panfrost_devfreq_update_utilization(struct panfrost_devfreq *pfdevfreq) { ktime_t now, last; now = ktime_get(); last = pfdevfreq->time_last_update; if (pfdevfreq->busy_count > 0) pfdevfreq->busy_time += ktime_sub(now, last); else pfdevfreq->idle_time += ktime_sub(now, last); pfdevfreq->time_last_update = now; } static int panfrost_devfreq_target(struct device *dev, unsigned long *freq, u32 flags) { struct dev_pm_opp *opp; opp = devfreq_recommended_opp(dev, freq, flags); if (IS_ERR(opp)) return PTR_ERR(opp); dev_pm_opp_put(opp); return dev_pm_opp_set_rate(dev, *freq); } static void panfrost_devfreq_reset(struct panfrost_devfreq *pfdevfreq) { pfdevfreq->busy_time = 0; pfdevfreq->idle_time = 0; pfdevfreq->time_last_update = ktime_get(); } static int panfrost_devfreq_get_dev_status(struct device *dev, struct devfreq_dev_status *status) { struct panfrost_device *pfdev = dev_get_drvdata(dev); struct panfrost_devfreq *pfdevfreq = &pfdev->pfdevfreq; unsigned long irqflags; status->current_frequency = clk_get_rate(pfdev->clock); spin_lock_irqsave(&pfdevfreq->lock, irqflags); panfrost_devfreq_update_utilization(pfdevfreq); status->total_time = ktime_to_ns(ktime_add(pfdevfreq->busy_time, pfdevfreq->idle_time)); status->busy_time = ktime_to_ns(pfdevfreq->busy_time); panfrost_devfreq_reset(pfdevfreq); spin_unlock_irqrestore(&pfdevfreq->lock, irqflags); dev_dbg(pfdev->dev, "busy %lu total %lu %lu %% freq %lu MHz\n", status->busy_time, status->total_time, status->busy_time / (status->total_time / 100), status->current_frequency / 1000 / 1000); return 0; } static struct devfreq_dev_profile panfrost_devfreq_profile = { .timer = DEVFREQ_TIMER_DELAYED, .polling_ms = 50, /* ~3 frames */ .target = panfrost_devfreq_target, .get_dev_status = panfrost_devfreq_get_dev_status, }; int panfrost_devfreq_init(struct panfrost_device *pfdev) { int ret; struct dev_pm_opp *opp; unsigned long cur_freq; struct device *dev = &pfdev->pdev->dev; struct devfreq *devfreq; struct thermal_cooling_device *cooling; struct panfrost_devfreq *pfdevfreq = &pfdev->pfdevfreq; ret = devm_pm_opp_set_regulators(dev, pfdev->comp->supply_names, pfdev->comp->num_supplies); if (ret) { /* Continue if the optional regulator is missing */ if (ret != -ENODEV) { DRM_DEV_ERROR(dev, "Couldn't set OPP regulators\n"); return ret; } } ret = devm_pm_opp_of_add_table(dev); if (ret) { /* Optional, continue without devfreq */ if (ret == -ENODEV) ret = 0; return ret; } pfdevfreq->opp_of_table_added = true; spin_lock_init(&pfdevfreq->lock); panfrost_devfreq_reset(pfdevfreq); cur_freq = clk_get_rate(pfdev->clock); opp = devfreq_recommended_opp(dev, &cur_freq, 0); if (IS_ERR(opp)) return PTR_ERR(opp); panfrost_devfreq_profile.initial_freq = cur_freq; dev_pm_opp_put(opp); /* * Setup default thresholds for the simple_ondemand governor. * The values are chosen based on experiments. */ pfdevfreq->gov_data.upthreshold = 45; pfdevfreq->gov_data.downdifferential = 5; devfreq = devm_devfreq_add_device(dev, &panfrost_devfreq_profile, DEVFREQ_GOV_SIMPLE_ONDEMAND, &pfdevfreq->gov_data); if (IS_ERR(devfreq)) { DRM_DEV_ERROR(dev, "Couldn't initialize GPU devfreq\n"); return PTR_ERR(devfreq); } pfdevfreq->devfreq = devfreq; cooling = devfreq_cooling_em_register(devfreq, NULL); if (IS_ERR(cooling)) DRM_DEV_INFO(dev, "Failed to register cooling device\n"); else pfdevfreq->cooling = cooling; return 0; } void panfrost_devfreq_fini(struct panfrost_device *pfdev) { struct panfrost_devfreq *pfdevfreq = &pfdev->pfdevfreq; if (pfdevfreq->cooling) { devfreq_cooling_unregister(pfdevfreq->cooling); pfdevfreq->cooling = NULL; } } void panfrost_devfreq_resume(struct panfrost_device *pfdev) { struct panfrost_devfreq *pfdevfreq = &pfdev->pfdevfreq; if (!pfdevfreq->devfreq) return; panfrost_devfreq_reset(pfdevfreq); devfreq_resume_device(pfdevfreq->devfreq); } void panfrost_devfreq_suspend(struct panfrost_device *pfdev) { struct panfrost_devfreq *pfdevfreq = &pfdev->pfdevfreq; if (!pfdevfreq->devfreq) return; devfreq_suspend_device(pfdevfreq->devfreq); } void panfrost_devfreq_record_busy(struct panfrost_devfreq *pfdevfreq) { unsigned long irqflags; if (!pfdevfreq->devfreq) return; spin_lock_irqsave(&pfdevfreq->lock, irqflags); panfrost_devfreq_update_utilization(pfdevfreq); pfdevfreq->busy_count++; spin_unlock_irqrestore(&pfdevfreq->lock, irqflags); } void panfrost_devfreq_record_idle(struct panfrost_devfreq *pfdevfreq) { unsigned long irqflags; if (!pfdevfreq->devfreq) return; spin_lock_irqsave(&pfdevfreq->lock, irqflags); panfrost_devfreq_update_utilization(pfdevfreq); WARN_ON(--pfdevfreq->busy_count < 0); spin_unlock_irqrestore(&pfdevfreq->lock, irqflags); }