On 19. 10. 30. 오전 7:00, Dmitry Osipenko wrote: > The ACTMON governor is interrupt-driven and currently hardware's polling > interval is fixed to 16ms in the driver. Devfreq supports variable polling > interval by the generic governors, let's re-use the generic interface for > changing of the polling interval. Now the polling interval can be changed > dynamically via /sys/class/devfreq/devfreq0/polling_interval. > > Signed-off-by: Dmitry Osipenko <digetx@xxxxxxxxx> > --- > drivers/devfreq/tegra30-devfreq.c | 35 ++++++++++++++++++++++++------- > 1 file changed, 28 insertions(+), 7 deletions(-) > > diff --git a/drivers/devfreq/tegra30-devfreq.c b/drivers/devfreq/tegra30-devfreq.c > index b745a973c35a..d0dd42856e5b 100644 > --- a/drivers/devfreq/tegra30-devfreq.c > +++ b/drivers/devfreq/tegra30-devfreq.c > @@ -218,7 +218,7 @@ static void tegra_devfreq_update_avg_wmark(struct tegra_devfreq *tegra, > { > u32 avg = dev->avg_count; > u32 avg_band_freq = tegra->max_freq * ACTMON_DEFAULT_AVG_BAND / KHZ; > - u32 band = avg_band_freq * ACTMON_SAMPLING_PERIOD; > + u32 band = avg_band_freq * tegra->devfreq->profile->polling_ms; > > device_writel(dev, avg + band, ACTMON_DEV_AVG_UPPER_WMARK); > > @@ -229,7 +229,7 @@ static void tegra_devfreq_update_avg_wmark(struct tegra_devfreq *tegra, > static void tegra_devfreq_update_wmark(struct tegra_devfreq *tegra, > struct tegra_devfreq_device *dev) > { > - u32 val = tegra->cur_freq * ACTMON_SAMPLING_PERIOD; > + u32 val = tegra->cur_freq * tegra->devfreq->profile->polling_ms; > > device_writel(dev, do_percent(val, dev->config->boost_up_threshold), > ACTMON_DEV_UPPER_WMARK); > @@ -308,7 +308,7 @@ static unsigned long actmon_device_target_freq(struct tegra_devfreq *tegra, > unsigned int avg_sustain_coef; > unsigned long target_freq; > > - target_freq = dev->avg_count / ACTMON_SAMPLING_PERIOD; > + target_freq = dev->avg_count / tegra->devfreq->profile->polling_ms; > avg_sustain_coef = 100 * 100 / dev->config->boost_up_threshold; > target_freq = do_percent(target_freq, avg_sustain_coef); > target_freq += dev->boost_freq; > @@ -465,7 +465,7 @@ static void tegra_actmon_configure_device(struct tegra_devfreq *tegra, > > dev->target_freq = tegra->cur_freq; > > - dev->avg_count = tegra->cur_freq * ACTMON_SAMPLING_PERIOD; > + dev->avg_count = tegra->cur_freq * tegra->devfreq->profile->polling_ms; > device_writel(dev, dev->avg_count, ACTMON_DEV_INIT_AVG); > > tegra_devfreq_update_avg_wmark(tegra, dev); > @@ -506,7 +506,11 @@ static int tegra_actmon_start(struct tegra_devfreq *tegra) > unsigned int i; > int err; > > - actmon_writel(tegra, ACTMON_SAMPLING_PERIOD - 1, > + if (!tegra->devfreq->profile->polling_ms || > + tegra->devfreq->stop_polling) I think that the access of 'devfreq->stop_polling' is not good on governor. It is possible to alter with DEVFREQ_GOV_START/STOP/SUSPEND/RESUME notification. > + return 0;> + > + actmon_writel(tegra, tegra->devfreq->profile->polling_ms - 1, > ACTMON_GLB_PERIOD_CTRL); > > /* > @@ -554,6 +558,10 @@ static int tegra_actmon_start(struct tegra_devfreq *tegra) > > static void tegra_actmon_stop(struct tegra_devfreq *tegra) > { > + if (!tegra->devfreq->profile->polling_ms || > + tegra->devfreq->stop_polling) ditto. > + return; > + > disable_irq(tegra->irq); > > cpufreq_unregister_notifier(&tegra->cpu_rate_change_nb, > @@ -623,7 +631,7 @@ static int tegra_devfreq_get_dev_status(struct device *dev, > stat->busy_time *= 100 / BUS_SATURATION_RATIO; > > /* Number of cycles in a sampling period */ > - stat->total_time = ACTMON_SAMPLING_PERIOD * cur_freq; > + stat->total_time = tegra->devfreq->profile->polling_ms * cur_freq; > > stat->busy_time = min(stat->busy_time, stat->total_time); > > @@ -631,7 +639,7 @@ static int tegra_devfreq_get_dev_status(struct device *dev, > } > > static struct devfreq_dev_profile tegra_devfreq_profile = { > - .polling_ms = 0, > + .polling_ms = ACTMON_SAMPLING_PERIOD, > .target = tegra_devfreq_target, > .get_dev_status = tegra_devfreq_get_dev_status, > }; > @@ -671,6 +679,7 @@ static int tegra_governor_event_handler(struct devfreq *devfreq, > unsigned int event, void *data) > { > struct tegra_devfreq *tegra = dev_get_drvdata(devfreq->dev.parent); > + unsigned int *new_delay = data; > int ret = 0; > > /* > @@ -690,6 +699,17 @@ static int tegra_governor_event_handler(struct devfreq *devfreq, > devfreq_monitor_stop(devfreq); > break; > > + case DEVFREQ_GOV_INTERVAL: > + if (*new_delay > 256) { Need to add the comment why the maximum delay is under 256 ms. > + ret = -EINVAL; > + break; > + } > + > + tegra_actmon_stop(tegra); > + devfreq_interval_update(devfreq, new_delay); > + ret = tegra_actmon_start(tegra); > + break; > + > case DEVFREQ_GOV_SUSPEND: > tegra_actmon_stop(tegra); > devfreq_monitor_suspend(devfreq); > @@ -709,6 +729,7 @@ static struct devfreq_governor tegra_devfreq_governor = { > .get_target_freq = tegra_governor_get_target, > .event_handler = tegra_governor_event_handler, > .immutable = true, > + .interrupt_driven = true, > }; > > static int tegra_devfreq_probe(struct platform_device *pdev) > -- Best Regards, Chanwoo Choi Samsung Electronics