/**
 * Copyright (c) 2015 Runtime Inc.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 * 
 *   http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

#include <assert.h>
#include <os/os.h>
#include <hal/hal_os_tick.h>

/*
 * XXX implement tickless mode.
 */
void
os_tick_idle(os_time_t ticks)
{
    OS_ASSERT_CRITICAL();
    __DSB();
    __WFI();
}

void
os_tick_init(uint32_t os_ticks_per_sec, int prio)
{
    uint32_t reload_val;

    reload_val = ((uint64_t)SystemCoreClock / os_ticks_per_sec) - 1;

    /* Set the system time ticker up */
    SysTick->LOAD = reload_val;
    SysTick->VAL = 0;
    SysTick->CTRL = 0x0007;

    /* Set the system tick priority */
    NVIC_SetPriority(SysTick_IRQn, prio);
}
