^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1) // SPDX-License-Identifier: GPL-2.0
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 2) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 3) * This file contains functions which manage high resolution tick
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 4) * related events.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 5) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 6) * Copyright(C) 2005-2006, Thomas Gleixner <tglx@linutronix.de>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 7) * Copyright(C) 2005-2007, Red Hat, Inc., Ingo Molnar
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 8) * Copyright(C) 2006-2007, Timesys Corp., Thomas Gleixner
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 9) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 10) #include <linux/cpu.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 11) #include <linux/err.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 12) #include <linux/hrtimer.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 13) #include <linux/interrupt.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 14) #include <linux/percpu.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 15) #include <linux/profile.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 16) #include <linux/sched.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 17)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 18) #include "tick-internal.h"
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 19)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 20) /**
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 21) * tick_program_event
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 22) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 23) int tick_program_event(ktime_t expires, int force)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 24) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 25) struct clock_event_device *dev = __this_cpu_read(tick_cpu_device.evtdev);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 26)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 27) if (unlikely(expires == KTIME_MAX)) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 28) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 29) * We don't need the clock event device any more, stop it.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 30) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 31) clockevents_switch_state(dev, CLOCK_EVT_STATE_ONESHOT_STOPPED);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 32) dev->next_event = KTIME_MAX;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 33) return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 34) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 35)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 36) if (unlikely(clockevent_state_oneshot_stopped(dev))) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 37) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 38) * We need the clock event again, configure it in ONESHOT mode
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 39) * before using it.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 40) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 41) clockevents_switch_state(dev, CLOCK_EVT_STATE_ONESHOT);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 42) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 43)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 44) return clockevents_program_event(dev, expires, force);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 45) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 46)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 47) /**
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 48) * tick_resume_onshot - resume oneshot mode
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 49) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 50) void tick_resume_oneshot(void)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 51) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 52) struct clock_event_device *dev = __this_cpu_read(tick_cpu_device.evtdev);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 53)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 54) clockevents_switch_state(dev, CLOCK_EVT_STATE_ONESHOT);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 55) clockevents_program_event(dev, ktime_get(), true);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 56) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 57)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 58) /**
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 59) * tick_setup_oneshot - setup the event device for oneshot mode (hres or nohz)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 60) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 61) void tick_setup_oneshot(struct clock_event_device *newdev,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 62) void (*handler)(struct clock_event_device *),
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 63) ktime_t next_event)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 64) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 65) newdev->event_handler = handler;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 66) clockevents_switch_state(newdev, CLOCK_EVT_STATE_ONESHOT);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 67) clockevents_program_event(newdev, next_event, true);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 68) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 69)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 70) /**
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 71) * tick_switch_to_oneshot - switch to oneshot mode
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 72) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 73) int tick_switch_to_oneshot(void (*handler)(struct clock_event_device *))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 74) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 75) struct tick_device *td = this_cpu_ptr(&tick_cpu_device);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 76) struct clock_event_device *dev = td->evtdev;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 77)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 78) if (!dev || !(dev->features & CLOCK_EVT_FEAT_ONESHOT) ||
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 79) !tick_device_is_functional(dev)) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 80)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 81) pr_info("Clockevents: could not switch to one-shot mode:");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 82) if (!dev) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 83) pr_cont(" no tick device\n");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 84) } else {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 85) if (!tick_device_is_functional(dev))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 86) pr_cont(" %s is not functional.\n", dev->name);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 87) else
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 88) pr_cont(" %s does not support one-shot mode.\n",
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 89) dev->name);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 90) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 91) return -EINVAL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 92) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 93)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 94) td->mode = TICKDEV_MODE_ONESHOT;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 95) dev->event_handler = handler;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 96) clockevents_switch_state(dev, CLOCK_EVT_STATE_ONESHOT);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 97) tick_broadcast_switch_to_oneshot();
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 98) return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 99) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 100)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 101) /**
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 102) * tick_check_oneshot_mode - check whether the system is in oneshot mode
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 103) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 104) * returns 1 when either nohz or highres are enabled. otherwise 0.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 105) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 106) int tick_oneshot_mode_active(void)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 107) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 108) unsigned long flags;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 109) int ret;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 110)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 111) local_irq_save(flags);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 112) ret = __this_cpu_read(tick_cpu_device.mode) == TICKDEV_MODE_ONESHOT;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 113) local_irq_restore(flags);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 114)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 115) return ret;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 116) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 117)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 118) #ifdef CONFIG_HIGH_RES_TIMERS
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 119) /**
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 120) * tick_init_highres - switch to high resolution mode
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 121) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 122) * Called with interrupts disabled.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 123) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 124) int tick_init_highres(void)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 125) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 126) return tick_switch_to_oneshot(hrtimer_interrupt);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 127) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 128) #endif
Orange Pi5 kernel
Deprecated Linux kernel 5.10.110 for OrangePi 5/5B/5+ boards
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