nuttx/arch/arm/src/s32k3xx/s32k3xx_timerisr.c
Jari van Ewijk dd1096695d Add initial support for NXP S32K3 MCU family
Co-authored-by: Peter van der Perk <peter.vanderperk@nxp.com>
2022-07-25 23:47:05 +08:00

134 lines
4.3 KiB
C

/****************************************************************************
* arch/arm/src/s32k3xx/s32k3xx_timerisr.c
*
* 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.
*
****************************************************************************/
/* Copyright 2022 NXP */
/****************************************************************************
* Included Files
****************************************************************************/
#include <nuttx/config.h>
#include <stdint.h>
#include <time.h>
#include <assert.h>
#include <debug.h>
#include <nuttx/arch.h>
#include <arch/board/board.h>
#include "nvic.h"
#include "arm_internal.h"
#include "clock/clock.h"
#include "s32k3xx_clockconfig.h"
/****************************************************************************
* Pre-processor Definitions
****************************************************************************/
/* The SysTick clock input (Fsystick) is determined by the CLKSOURCE file of
* the SysTick CSR register: The CLKSOURCE field in SysTick Control and
* Status register selects either the core clock (when CLKSOURCE = 1) or a
* divide-by-16 of the core clock (when CLKSOURCE = 0).
*
* The desired timer interrupt frequency is provided by the definition
* CLK_TCK (see include/time.h). CLK_TCK defines the desired number of
* system clock ticks per second. That value is a user configurable setting
* that defaults to 100 (100 ticks per second = 10 MS interval).
*
* reload = (Fsystick / CLK_TICK) - 1
*/
#define SYSTICK_RELOAD(coreclk) (((coreclk) / CLK_TCK) - 1)
/****************************************************************************
* Private Functions
****************************************************************************/
/****************************************************************************
* Function: s32k3xx_timerisr
*
* Description:
* The timer ISR will perform a variety of services for various portions
* of the systems.
*
****************************************************************************/
static int s32k3xx_timerisr(int irq, uint32_t *regs, void *arg)
{
/* Process timer interrupt */
nxsched_process_timer();
return 0;
}
/****************************************************************************
* Public Functions
****************************************************************************/
/****************************************************************************
* Function: up_timer_initialize
*
* Description:
* This function is called during start-up to initialize
* the timer interrupt.
*
****************************************************************************/
void up_timer_initialize(void)
{
uint32_t coreclk;
uint32_t reload;
/* Make sure that the SYSTICK clock source is set to use the SysTick
* function clock (CLKSOURCE==1).
*/
putreg32(NVIC_SYSTICK_CTRL_CLKSOURCE, NVIC_SYSTICK_CTRL);
/* Get the reload value */
coreclk = s32k3xx_get_coreclk();
reload = SYSTICK_RELOAD(coreclk);
/* The size of the reload field is 24 bits. */
DEBUGASSERT(reload <= 0x00ffffff);
/* Configure SysTick to interrupt at the requested rate */
putreg32(reload, NVIC_SYSTICK_RELOAD);
putreg32(0, NVIC_SYSTICK_CURRENT);
/* Attach the timer interrupt vector */
irq_attach(S32K3XX_IRQ_SYSTICK, (xcpt_t)s32k3xx_timerisr, NULL);
/* Enable SysTick interrupts */
putreg32((NVIC_SYSTICK_CTRL_CLKSOURCE | NVIC_SYSTICK_CTRL_TICKINT |
NVIC_SYSTICK_CTRL_ENABLE), NVIC_SYSTICK_CTRL);
/* And enable the timer interrupt */
up_enable_irq(S32K3XX_IRQ_SYSTICK);
}