| /* |
| * Licensed to the Apache Software Foundation (ASF) under one |
| * or more contributor license agreements. See the NOTICE file |
| * distributed with this work for additional information |
| * regarding copyright ownership. The ASF licenses this file |
| * to you 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 <stdio.h> |
| #include "os/mynewt.h" |
| #include <hal/hal_os_tick.h> |
| |
| #include "mcu/cmsis_nvic.h" |
| |
| #include "fsl_pit.h" |
| |
| static void nxp_pit0_timer_handler(void) |
| { |
| uint32_t sr; |
| |
| OS_ENTER_CRITICAL(sr); |
| |
| /* Clear interrupt flag.*/ |
| PIT_ClearStatusFlags(PIT, kPIT_Chnl_0, PIT_TFLG_TIF_MASK); |
| os_time_advance(1); |
| |
| OS_EXIT_CRITICAL(sr); |
| } |
| |
| 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) |
| { |
| pit_config_t pitConfig; |
| uint32_t sr; |
| |
| uint32_t ticks_per_ostick = 1000000U / os_ticks_per_sec; /* 1000/s */ |
| |
| PIT_GetDefaultConfig(&pitConfig); |
| pitConfig.enableRunInDebug = true; |
| PIT_Init(PIT, &pitConfig); |
| |
| /* Clear interrupt flag.*/ |
| PIT_ClearStatusFlags(PIT, kPIT_Chnl_0, PIT_TFLG_TIF_MASK); |
| |
| /* Set timer period for channel 0 */ |
| PIT_SetTimerPeriod(PIT, kPIT_Chnl_0, USEC_TO_COUNT(ticks_per_ostick, CLOCK_GetFreq(kCLOCK_BusClk))); |
| |
| /* Enable timer interrupts for channel 0 */ |
| PIT_EnableInterrupts(PIT, kPIT_Chnl_0, kPIT_TimerInterruptEnable); |
| |
| /* disable interrupts */ |
| OS_ENTER_CRITICAL(sr); |
| |
| /* Set isr in vector table and enable interrupt */ |
| NVIC_SetPriority(PIT0_IRQn, prio); |
| NVIC_SetVector(PIT0_IRQn, (uint32_t)nxp_pit0_timer_handler); |
| /* Enable at the NVIC */ |
| EnableIRQ(PIT0_IRQn); |
| |
| /* Start channel 0 */ |
| PIT_StartTimer(PIT, kPIT_Chnl_0); |
| |
| OS_EXIT_CRITICAL(sr); |
| } |