This driver boosts enumerated devfreq devices upon input, and allows for boosting specific devfreq devices on other custom events. The boost frequencies for this driver should be set so that frame drops are near-zero at the boosted frequencies and power consumption is minimized at said frequencies. The goal of this driver is to provide an interface to achieve optimal device performance by requesting boosts on key events, such as when a frame is ready to rendered to the display. Currently, support is only present for boosting the cpu-llcc-ddr-bw devfreq device, but the driver is structured in a way that makes it easy to add support for new boostable devfreq devices in the future. Signed-off-by: Sultan Alsawaf <sultan@kerneltoast.com>fourteen
Sultan Alsawaf
4 years ago
committed by
Jenna
parent
eaf4e78745
commit
beca6e300f
@ -0,0 +1,341 @@ |
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// SPDX-License-Identifier: GPL-2.0
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/*
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* Copyright (C) 2018-2021 Sultan Alsawaf <sultan@kerneltoast.com>. |
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*/ |
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#define pr_fmt(fmt) "devfreq_boost: " fmt |
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#include <linux/devfreq_boost.h> |
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#include <linux/input.h> |
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#include <linux/kthread.h> |
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#include <linux/msm_drm_notify.h> |
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#include <linux/slab.h> |
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#include <uapi/linux/sched/types.h> |
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enum { |
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SCREEN_OFF, |
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INPUT_BOOST, |
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MAX_BOOST |
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}; |
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struct boost_dev { |
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struct devfreq *df; |
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struct delayed_work input_unboost; |
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struct delayed_work max_unboost; |
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wait_queue_head_t boost_waitq; |
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atomic_long_t max_boost_expires; |
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unsigned long boost_freq; |
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unsigned long state; |
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}; |
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struct df_boost_drv { |
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struct boost_dev devices[DEVFREQ_MAX]; |
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struct notifier_block msm_drm_notif; |
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}; |
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static void devfreq_input_unboost(struct work_struct *work); |
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static void devfreq_max_unboost(struct work_struct *work); |
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#define BOOST_DEV_INIT(b, dev, freq) .devices[dev] = { \ |
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.input_unboost = \
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__DELAYED_WORK_INITIALIZER((b).devices[dev].input_unboost, \
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devfreq_input_unboost, 0), \
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.max_unboost = \
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__DELAYED_WORK_INITIALIZER((b).devices[dev].max_unboost, \
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devfreq_max_unboost, 0), \
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.boost_waitq = \
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__WAIT_QUEUE_HEAD_INITIALIZER((b).devices[dev].boost_waitq), \
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.boost_freq = freq \
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} |
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static struct df_boost_drv df_boost_drv_g __read_mostly = { |
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BOOST_DEV_INIT(df_boost_drv_g, DEVFREQ_CPU_LLCC_DDR_BW, |
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CONFIG_DEVFREQ_CPU_LLCC_DDR_BW_BOOST_FREQ) |
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}; |
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static void __devfreq_boost_kick(struct boost_dev *b) |
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{ |
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if (!READ_ONCE(b->df) || test_bit(SCREEN_OFF, &b->state)) |
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return; |
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set_bit(INPUT_BOOST, &b->state); |
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if (!mod_delayed_work(system_unbound_wq, &b->input_unboost, |
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msecs_to_jiffies(CONFIG_DEVFREQ_INPUT_BOOST_DURATION_MS))) { |
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/* Set the bit again in case we raced with the unboost worker */ |
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set_bit(INPUT_BOOST, &b->state); |
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wake_up(&b->boost_waitq); |
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} |
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} |
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void devfreq_boost_kick(enum df_device device) |
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{ |
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struct df_boost_drv *d = &df_boost_drv_g; |
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__devfreq_boost_kick(&d->devices[device]); |
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} |
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static void __devfreq_boost_kick_max(struct boost_dev *b, |
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unsigned int duration_ms) |
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{ |
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unsigned long boost_jiffies, curr_expires, new_expires; |
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if (!READ_ONCE(b->df) || test_bit(SCREEN_OFF, &b->state)) |
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return; |
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boost_jiffies = msecs_to_jiffies(duration_ms); |
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do { |
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curr_expires = atomic_long_read(&b->max_boost_expires); |
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new_expires = jiffies + boost_jiffies; |
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/* Skip this boost if there's a longer boost in effect */ |
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if (time_after(curr_expires, new_expires)) |
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return; |
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} while (atomic_long_cmpxchg(&b->max_boost_expires, curr_expires, |
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new_expires) != curr_expires); |
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set_bit(MAX_BOOST, &b->state); |
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if (!mod_delayed_work(system_unbound_wq, &b->max_unboost, |
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boost_jiffies)) { |
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/* Set the bit again in case we raced with the unboost worker */ |
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set_bit(MAX_BOOST, &b->state); |
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wake_up(&b->boost_waitq); |
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} |
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} |
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void devfreq_boost_kick_max(enum df_device device, unsigned int duration_ms) |
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{ |
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struct df_boost_drv *d = &df_boost_drv_g; |
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__devfreq_boost_kick_max(&d->devices[device], duration_ms); |
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} |
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void devfreq_register_boost_device(enum df_device device, struct devfreq *df) |
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{ |
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struct df_boost_drv *d = &df_boost_drv_g; |
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struct boost_dev *b; |
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df->is_boost_device = true; |
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b = &d->devices[device]; |
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WRITE_ONCE(b->df, df); |
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} |
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static void devfreq_input_unboost(struct work_struct *work) |
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{ |
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struct boost_dev *b = container_of(to_delayed_work(work), typeof(*b), |
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input_unboost); |
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clear_bit(INPUT_BOOST, &b->state); |
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wake_up(&b->boost_waitq); |
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} |
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static void devfreq_max_unboost(struct work_struct *work) |
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{ |
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struct boost_dev *b = container_of(to_delayed_work(work), typeof(*b), |
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max_unboost); |
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clear_bit(MAX_BOOST, &b->state); |
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wake_up(&b->boost_waitq); |
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} |
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static void devfreq_update_boosts(struct boost_dev *b, unsigned long state) |
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{ |
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struct devfreq *df = b->df; |
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mutex_lock(&df->lock); |
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if (state & BIT(SCREEN_OFF)) { |
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df->min_freq = df->profile->freq_table[0]; |
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df->max_boost = false; |
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} else { |
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df->min_freq = state & BIT(INPUT_BOOST) ? |
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min(b->boost_freq, df->max_freq) : |
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df->profile->freq_table[0]; |
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df->max_boost = state & BIT(MAX_BOOST); |
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} |
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update_devfreq(df); |
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mutex_unlock(&df->lock); |
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} |
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static int devfreq_boost_thread(void *data) |
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{ |
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static const struct sched_param sched_max_rt_prio = { |
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.sched_priority = MAX_RT_PRIO - 1 |
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}; |
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struct boost_dev *b = data; |
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unsigned long old_state = 0; |
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sched_setscheduler_nocheck(current, SCHED_FIFO, &sched_max_rt_prio); |
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while (1) { |
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bool should_stop = false; |
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unsigned long curr_state; |
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wait_event_interruptible(b->boost_waitq, |
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(curr_state = READ_ONCE(b->state)) != old_state || |
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(should_stop = kthread_should_stop())); |
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if (should_stop) |
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break; |
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if (old_state != curr_state) { |
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devfreq_update_boosts(b, curr_state); |
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old_state = curr_state; |
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} |
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} |
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return 0; |
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} |
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static int msm_drm_notifier_cb(struct notifier_block *nb, |
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unsigned long action, void *data) |
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{ |
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struct df_boost_drv *d = container_of(nb, typeof(*d), msm_drm_notif); |
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int i, *blank = ((struct msm_drm_notifier *)data)->data; |
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/* Parse DRM blank events as soon as they occur */ |
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if (action != MSM_DRM_EARLY_EVENT_BLANK) |
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return NOTIFY_OK; |
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/* Boost when the screen turns on and unboost when it turns off */ |
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for (i = 0; i < DEVFREQ_MAX; i++) { |
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struct boost_dev *b = &d->devices[i]; |
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if (*blank == MSM_DRM_BLANK_UNBLANK) { |
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clear_bit(SCREEN_OFF, &b->state); |
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__devfreq_boost_kick_max(b, |
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CONFIG_DEVFREQ_WAKE_BOOST_DURATION_MS); |
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} else { |
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set_bit(SCREEN_OFF, &b->state); |
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wake_up(&b->boost_waitq); |
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} |
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} |
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return NOTIFY_OK; |
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} |
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static void devfreq_boost_input_event(struct input_handle *handle, |
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unsigned int type, unsigned int code, |
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int value) |
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{ |
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struct df_boost_drv *d = handle->handler->private; |
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int i; |
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for (i = 0; i < DEVFREQ_MAX; i++) |
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__devfreq_boost_kick(&d->devices[i]); |
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} |
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static int devfreq_boost_input_connect(struct input_handler *handler, |
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struct input_dev *dev, |
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const struct input_device_id *id) |
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{ |
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struct input_handle *handle; |
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int ret; |
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handle = kzalloc(sizeof(*handle), GFP_KERNEL); |
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if (!handle) |
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return -ENOMEM; |
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handle->dev = dev; |
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handle->handler = handler; |
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handle->name = "devfreq_boost_handle"; |
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ret = input_register_handle(handle); |
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if (ret) |
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goto free_handle; |
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ret = input_open_device(handle); |
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if (ret) |
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goto unregister_handle; |
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return 0; |
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unregister_handle: |
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input_unregister_handle(handle); |
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free_handle: |
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kfree(handle); |
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return ret; |
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} |
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static void devfreq_boost_input_disconnect(struct input_handle *handle) |
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{ |
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input_close_device(handle); |
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input_unregister_handle(handle); |
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kfree(handle); |
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} |
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static const struct input_device_id devfreq_boost_ids[] = { |
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/* Multi-touch touchscreen */ |
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{ |
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.flags = INPUT_DEVICE_ID_MATCH_EVBIT | |
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INPUT_DEVICE_ID_MATCH_ABSBIT, |
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.evbit = { BIT_MASK(EV_ABS) }, |
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.absbit = { [BIT_WORD(ABS_MT_POSITION_X)] = |
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BIT_MASK(ABS_MT_POSITION_X) | |
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BIT_MASK(ABS_MT_POSITION_Y) } |
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}, |
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/* Touchpad */ |
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{ |
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.flags = INPUT_DEVICE_ID_MATCH_KEYBIT | |
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INPUT_DEVICE_ID_MATCH_ABSBIT, |
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.keybit = { [BIT_WORD(BTN_TOUCH)] = BIT_MASK(BTN_TOUCH) }, |
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.absbit = { [BIT_WORD(ABS_X)] = |
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BIT_MASK(ABS_X) | BIT_MASK(ABS_Y) } |
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}, |
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/* Keypad */ |
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{ |
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.flags = INPUT_DEVICE_ID_MATCH_EVBIT, |
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.evbit = { BIT_MASK(EV_KEY) } |
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}, |
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{ } |
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}; |
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static struct input_handler devfreq_boost_input_handler = { |
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.event = devfreq_boost_input_event, |
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.connect = devfreq_boost_input_connect, |
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.disconnect = devfreq_boost_input_disconnect, |
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.name = "devfreq_boost_handler", |
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.id_table = devfreq_boost_ids |
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}; |
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static int __init devfreq_boost_init(void) |
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{ |
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struct df_boost_drv *d = &df_boost_drv_g; |
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struct task_struct *thread[DEVFREQ_MAX]; |
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int i, ret; |
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for (i = 0; i < DEVFREQ_MAX; i++) { |
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struct boost_dev *b = &d->devices[i]; |
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thread[i] = kthread_run(devfreq_boost_thread, b, |
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"devfreq_boostd/%d", i); |
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if (IS_ERR(thread[i])) { |
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ret = PTR_ERR(thread[i]); |
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pr_err("Failed to create kthread, err: %d\n", ret); |
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goto stop_kthreads; |
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} |
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} |
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devfreq_boost_input_handler.private = d; |
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ret = input_register_handler(&devfreq_boost_input_handler); |
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if (ret) { |
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pr_err("Failed to register input handler, err: %d\n", ret); |
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goto stop_kthreads; |
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} |
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d->msm_drm_notif.notifier_call = msm_drm_notifier_cb; |
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d->msm_drm_notif.priority = INT_MAX; |
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ret = msm_drm_register_client(&d->msm_drm_notif); |
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if (ret) { |
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pr_err("Failed to register msm_drm notifier, err: %d\n", ret); |
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goto unregister_handler; |
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} |
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return 0; |
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unregister_handler: |
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input_unregister_handler(&devfreq_boost_input_handler); |
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stop_kthreads: |
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while (i--) |
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kthread_stop(thread[i]); |
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return ret; |
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} |
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late_initcall(devfreq_boost_init); |
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@ -0,0 +1,34 @@ |
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/* SPDX-License-Identifier: GPL-2.0 */ |
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/*
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* Copyright (C) 2018-2021 Sultan Alsawaf <sultan@kerneltoast.com>. |
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*/ |
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#ifndef _DEVFREQ_BOOST_H_ |
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#define _DEVFREQ_BOOST_H_ |
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#include <linux/devfreq.h> |
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enum df_device { |
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DEVFREQ_CPU_LLCC_DDR_BW, |
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DEVFREQ_MAX |
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}; |
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#ifdef CONFIG_DEVFREQ_BOOST |
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void devfreq_boost_kick(enum df_device device); |
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void devfreq_boost_kick_max(enum df_device device, unsigned int duration_ms); |
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void devfreq_register_boost_device(enum df_device device, struct devfreq *df); |
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#else |
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static inline |
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void devfreq_boost_kick(enum df_device device) |
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{ |
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} |
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static inline |
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void devfreq_boost_kick_max(enum df_device device, unsigned int duration_ms) |
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{ |
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} |
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static inline |
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void devfreq_register_boost_device(enum df_device device, struct devfreq *df) |
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{ |
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} |
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#endif |
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#endif /* _DEVFREQ_BOOST_H_ */ |
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