zephyr/drivers/timer/mcux_os_timer.c

130 lines
3.0 KiB
C

/*
* Copyright (c) 2021 NXP
*
* SPDX-License-Identifier: Apache-2.0
*/
#define DT_DRV_COMPAT nxp_os_timer
#include <drivers/timer/system_timer.h>
#include <sys_clock.h>
#include <spinlock.h>
#include "fsl_ostimer.h"
#include "fsl_power.h"
#define CYC_PER_TICK ((uint32_t)((uint64_t)sys_clock_hw_cycles_per_sec() \
/ (uint64_t)CONFIG_SYS_CLOCK_TICKS_PER_SEC))
#define MAX_CYC INT_MAX
#define MAX_TICKS ((MAX_CYC - CYC_PER_TICK) / CYC_PER_TICK)
#define MIN_DELAY 1000
#define TICKLESS IS_ENABLED(CONFIG_TICKLESS_KERNEL)
static struct k_spinlock lock;
static uint64_t last_count;
static OSTIMER_Type *base;
static void mcux_lpc_ostick_isr(void *arg)
{
ARG_UNUSED(arg);
k_spinlock_key_t key = k_spin_lock(&lock);
uint64_t now = OSTIMER_GetCurrentTimerValue(base);
uint32_t dticks = (uint32_t)((now - last_count) / CYC_PER_TICK);
/* Clear interrupt flag by writing 1. */
base->OSEVENT_CTRL &= ~OSTIMER_OSEVENT_CTRL_OSTIMER_INTENA_MASK;
last_count += dticks * CYC_PER_TICK;
if (!TICKLESS) {
uint64_t next = last_count + CYC_PER_TICK;
if ((int64_t)(next - now) < MIN_DELAY) {
next += CYC_PER_TICK;
}
OSTIMER_SetMatchValue(base, next, NULL);
}
k_spin_unlock(&lock, key);
sys_clock_announce(IS_ENABLED(CONFIG_TICKLESS_KERNEL) ? dticks : 1);
}
int sys_clock_driver_init(const struct device *device)
{
ARG_UNUSED(device);
/* Configure event timer's ISR */
IRQ_CONNECT(DT_INST_IRQN(0), DT_INST_IRQ(0, priority),
mcux_lpc_ostick_isr, NULL, 0);
base = (OSTIMER_Type *)DT_INST_REG_ADDR(0);
EnableDeepSleepIRQ(DT_INST_IRQN(0));
/* Initialize the OS timer, setting clock configuration. */
OSTIMER_Init(base);
last_count = OSTIMER_GetCurrentTimerValue(base);
OSTIMER_SetMatchValue(base, last_count + CYC_PER_TICK, NULL);
/* Enable event timer interrupt */
irq_enable(DT_INST_IRQN(0));
return 0;
}
void sys_clock_set_timeout(int32_t ticks, bool idle)
{
ARG_UNUSED(idle);
if (!IS_ENABLED(CONFIG_TICKLESS_KERNEL)) {
/* Only for tickless kernel system */
return;
}
ticks = ticks == K_TICKS_FOREVER ? MAX_TICKS : ticks;
ticks = CLAMP(ticks - 1, 0, (int32_t)MAX_TICKS);
k_spinlock_key_t key = k_spin_lock(&lock);
uint64_t now = OSTIMER_GetCurrentTimerValue(base);
uint32_t adj, cyc = ticks * CYC_PER_TICK;
/* Round up to next tick boundary. */
adj = (uint32_t)(now - last_count) + (CYC_PER_TICK - 1);
if (cyc <= MAX_CYC - adj) {
cyc += adj;
} else {
cyc = MAX_CYC;
}
cyc = (cyc / CYC_PER_TICK) * CYC_PER_TICK;
if ((int32_t)(cyc + last_count - now) < MIN_DELAY) {
cyc += CYC_PER_TICK;
}
OSTIMER_SetMatchValue(base, cyc + last_count, NULL);
k_spin_unlock(&lock, key);
}
uint32_t sys_clock_elapsed(void)
{
if (!IS_ENABLED(CONFIG_TICKLESS_KERNEL)) {
/* Always return 0 for tickful kernel system */
return 0;
}
k_spinlock_key_t key = k_spin_lock(&lock);
uint32_t ret = ((uint32_t)OSTIMER_GetCurrentTimerValue(base) -
(uint32_t)last_count) / CYC_PER_TICK;
k_spin_unlock(&lock, key);
return ret;
}
uint32_t sys_clock_cycle_get_32(void)
{
return (uint32_t)OSTIMER_GetCurrentTimerValue(base);
}