/*
 * Copyright (c) 2018 Intel Corporation
 *
 * SPDX-License-Identifier: Apache-2.0
 */

#include <stdio.h>
#include <string.h>
#include <kernel_structs.h>
#include <ksched.h>
#include <cmsis_os2.h>

/* Currently the timing implementations for timeouts and osDelay
 * assume that the arguments are in Zephyr ticks, even though ARM
 * documentation and at least some of our test code assume they are
 * milliseconds.  They must match for now.
 */
BUILD_ASSERT(CONFIG_SYS_CLOCK_TICKS_PER_SEC == 1000);

extern u32_t z_tick_get_32(void);

/**
 * @brief Get RTOS Kernel Information.
 */
osStatus_t osKernelGetInfo(osVersion_t *version, char *id_buf, uint32_t id_size)
{
	u32_t ver = sys_kernel_version_get();

	if (version != NULL) {
		version->api = ver;
		version->kernel = ver;
	}

	if ((id_buf != NULL) && (version != NULL)) {
		snprintf(id_buf, id_size,
			 "Zephyr V%2"PRIu32".%2"PRIu32".%2"PRIu32,
			 SYS_KERNEL_VER_MAJOR(version->kernel),
			 SYS_KERNEL_VER_MINOR(version->kernel),
			 SYS_KERNEL_VER_PATCHLEVEL(version->kernel));
	}

	return osOK;
}

/**
 * @brief Lock the RTOS Kernel scheduler.
 */
int32_t osKernelLock(void)
{
	int temp = _current->base.sched_locked;

	if (k_is_in_isr()) {
		return osErrorISR;
	}

	k_sched_lock();

	return temp;
}

/**
 * @brief Unlock the RTOS Kernel scheduler.
 */
int32_t osKernelUnlock(void)
{
	int temp = _current->base.sched_locked;

	if (k_is_in_isr()) {
		return osErrorISR;
	}

	k_sched_unlock();

	return temp;
}

/**
 * @brief Restore the RTOS Kernel scheduler lock state.
 */
int32_t osKernelRestoreLock(int32_t lock)
{
	_current->base.sched_locked = lock;

	if (k_is_in_isr()) {
		return osErrorISR;
	}

	if (lock < 0) {
		return 1;       /* locked */
	} else {
		return 0;       /* not locked */
	}
}

/**
 * @brief Get the RTOS kernel tick count.
 */
uint32_t osKernelGetTickCount(void)
{
	return z_tick_get_32();
}

/**
 * @brief Get the RTOS kernel tick frequency.
 */
uint32_t osKernelGetTickFreq(void)
{
	return CONFIG_SYS_CLOCK_TICKS_PER_SEC;
}

/**
 * @brief Get the RTOS kernel system timer count.
 */
uint32_t osKernelGetSysTimerCount(void)
{
	return k_cycle_get_32();
}

/**
 * @brief Get the RTOS kernel system timer frequency.
 */
uint32_t osKernelGetSysTimerFreq(void)
{
	return sys_clock_hw_cycles_per_sec();
}

/**
 * @brief Wait for Timeout (Time Delay).
 */
osStatus_t osDelay(uint32_t ticks)
{
	if (k_is_in_isr()) {
		return osErrorISR;
	}

	k_sleep(__ticks_to_ms(ticks));

	return osOK;
}

/**
 * @brief Wait until specified time.
 */
osStatus_t osDelayUntil(uint32_t ticks)
{
	u32_t ticks_elapsed;

	if (k_is_in_isr()) {
		return osErrorISR;
	}

	ticks_elapsed = osKernelGetTickCount();
	k_sleep(__ticks_to_ms(ticks - ticks_elapsed));

	return osOK;
}