152 lines
5.3 KiB
C
152 lines
5.3 KiB
C
/****************************************************************************
|
|
* arch/arm/src/lpc43xx/lpc43_timerisr.c
|
|
*
|
|
* Copyright (C) 2012 Gregory Nutt. All rights reserved.
|
|
* Author: Gregory Nutt <gnutt@nuttx.org>
|
|
*
|
|
* Redistribution and use in source and binary forms, with or without
|
|
* modification, are permitted provided that the following conditions
|
|
* are met:
|
|
*
|
|
* 1. Redistributions of source code must retain the above copyright
|
|
* notice, this list of conditions and the following disclaimer.
|
|
* 2. Redistributions in binary form must reproduce the above copyright
|
|
* notice, this list of conditions and the following disclaimer in
|
|
* the documentation and/or other materials provided with the
|
|
* distribution.
|
|
* 3. Neither the name NuttX nor the names of its contributors may be
|
|
* used to endorse or promote products derived from this software
|
|
* without specific prior written permission.
|
|
*
|
|
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
|
|
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
|
|
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
|
|
* FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
|
|
* COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
|
|
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
|
|
* BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
|
|
* OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
|
|
* AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
|
|
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
|
|
* ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
|
|
* POSSIBILITY OF SUCH DAMAGE.
|
|
*
|
|
****************************************************************************/
|
|
|
|
/****************************************************************************
|
|
* Included Files
|
|
****************************************************************************/
|
|
|
|
#include <nuttx/config.h>
|
|
|
|
#include <stdint.h>
|
|
#include <time.h>
|
|
#include <debug.h>
|
|
|
|
#include <nuttx/arch.h>
|
|
#include <arch/board/board.h>
|
|
|
|
#include "nvic.h"
|
|
#include "clock_internal.h"
|
|
#include "up_internal.h"
|
|
#include "up_arch.h"
|
|
|
|
#include "chip.h"
|
|
|
|
/****************************************************************************
|
|
* Definitions
|
|
****************************************************************************/
|
|
|
|
/* 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).
|
|
*
|
|
* The Clock Source: Either the internal CCLK or external STCLK (P3.26) clock
|
|
* as the source in the STCTRL register. This file alwyays configures the
|
|
* timer to use CCLK as its source.
|
|
*/
|
|
|
|
#define SYSTICK_RELOAD ((LPC43_CCLK / CLK_TCK) - 1)
|
|
|
|
/* The size of the reload field is 24 bits. Verify that the reload value
|
|
* will fit in the reload register.
|
|
*/
|
|
|
|
#if SYSTICK_RELOAD > 0x00ffffff
|
|
# error SYSTICK_RELOAD exceeds the range of the RELOAD register
|
|
#endif
|
|
|
|
/****************************************************************************
|
|
* Private Types
|
|
****************************************************************************/
|
|
|
|
/****************************************************************************
|
|
* Private Function Prototypes
|
|
****************************************************************************/
|
|
|
|
/****************************************************************************
|
|
* Global Functions
|
|
****************************************************************************/
|
|
|
|
/****************************************************************************
|
|
* Function: up_timerisr
|
|
*
|
|
* Description:
|
|
* The timer ISR will perform a variety of services for various portions
|
|
* of the systems.
|
|
*
|
|
****************************************************************************/
|
|
|
|
int up_timerisr(int irq, uint32_t *regs)
|
|
{
|
|
/* Process timer interrupt */
|
|
|
|
sched_process_timer();
|
|
return 0;
|
|
}
|
|
|
|
/****************************************************************************
|
|
* Function: up_timerinit
|
|
*
|
|
* Description:
|
|
* This function is called during start-up to initialize
|
|
* the timer interrupt.
|
|
*
|
|
****************************************************************************/
|
|
|
|
void up_timerinit(void)
|
|
{
|
|
uint32_t regval;
|
|
|
|
/* Set the SysTick interrupt to the default priority */
|
|
|
|
regval = getreg32(NVIC_SYSH12_15_PRIORITY);
|
|
regval &= ~NVIC_SYSH_PRIORITY_PR15_MASK;
|
|
regval |= (LPC43M4_SYSH_PRIORITY_DEFAULT << NVIC_SYSH_PRIORITY_PR15_SHIFT);
|
|
putreg32(regval, NVIC_SYSH12_15_PRIORITY);
|
|
|
|
/* Make sure that the SYSTICK clock source is set to use the LPC43xx CCLK */
|
|
|
|
regval = getreg32(NVIC_SYSTICK_CTRL);
|
|
regval |= NVIC_SYSTICK_CTRL_CLKSOURCE;
|
|
putreg32(regval, NVIC_SYSTICK_CTRL);
|
|
|
|
/* Configure SysTick to interrupt at the requested rate */
|
|
|
|
putreg32(SYSTICK_RELOAD, NVIC_SYSTICK_RELOAD);
|
|
|
|
/* Attach the timer interrupt vector */
|
|
|
|
(void)irq_attach(LPC43_IRQ_SYSTICK, (xcpt_t)up_timerisr);
|
|
|
|
/* 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(LPC43_IRQ_SYSTICK);
|
|
}
|