interrupt.c

RT-Thread是发展中的下一代微内核嵌入式实时操作系统

/*
 * File      : interrupt.c
 * This file is part of RT-Thread RTOS
 * COPYRIGHT (C) 2006, RT-Thread Development Team
 *
 * The license and distribution terms for this file may be
 * found in the file LICENSE in this distribution or at
 * http://openlab.rt-thread.com/license/LICENSE
 *
 * Change Logs:
 * Date           Author       Notes
 * 2006-09-02     Vai          Nintendo DS version
 */

#include <rtthread.h>
#include "nds.h"

#define MAX_HANDLERS	22

/*
 * Enable IRQs
 */
#define irq_enable()                    \
	({                                  \
		unsigned long temp;             \
	__asm__ __volatile__(               \
	"mrs	%0, cpsr\n"                 \
    "bic	%0, %0, #128\n"             \
    "msr	cpsr_c, %0"                 \
	: "=r" (temp)                       \
	:                                   \
	: "memory", "cc");                  \
	})

/*
 * Disable IRQs
 */
#define irq_disable()                   \
	({                                  \
		unsigned long temp;             \
	__asm__ __volatile__(               \
	"mrs	%0, cpsr\n"                 \
    "orr	%0, %0, #128\n"             \
    "msr	cpsr_c, %0"                 \
	: "=r" (temp)                       \
	:                                   \
	: "memory", "cc");                  \
	})

extern rt_uint32_t rt_interrupt_nest;

/* exception and interrupt handler table */
rt_isr_handler_t isr_table[MAX_HANDLERS];
rt_uint32_t rt_interrupt_from_thread, rt_interrupt_to_thread;
rt_uint32_t rt_thread_switch_interrput_flag;

/**
 * @addtogroup nds
 */
/*@{*/

void rt_hw_interrupt_handle(int vector)
{
	rt_kprintf("Unhandled interrupt %d occured!!!\n", vector);
}

void rt_hw_interrupt_init()
{
    register int i;

        /* ACK all interrupt */
    *((volatile unsigned long *) NDS_IE) = 0;

    /* init exceptions table */
    for(i=0; i<MAX_HANDLERS; i++)
    {
        isr_table[i] = rt_hw_interrupt_handle;
    }

    /* init interrupt nest, and context in thread sp */
    rt_interrupt_nest = 0;
    rt_interrupt_from_thread = 0;
    rt_interrupt_to_thread = 0;
    rt_thread_switch_interrput_flag = 0;
}

void rt_hw_interrupt_mask(int vector)
{
    *((volatile unsigned long *) NDS_IE) &= ~(0x1 << vector);
}

void rt_hw_interrupt_umask(int vector)
{
    if (INTGLOBAL == vector)
    {
        *((volatile unsigned long *) NDS_IME) = 0x0001;
        irq_enable();
    }
    
    *((volatile unsigned long *) NDS_IE) |= (0x1 << vector);
}

void rt_hw_interrupt_install(int vector, rt_isr_handler_t new_handler, rt_isr_handler_t *old_handler)
{
	if(vector < MAX_HANDLERS)
	{
		if (old_handler != RT_NULL) *old_handler = isr_table[vector];
		if (new_handler != RT_NULL) isr_table[vector] = new_handler;
	}
}

void rt_hw_interrupt_umaskall (void)
{
    /* global interrupt enable bit */
    *((volatile unsigned long *) NDS_IME) = 0x0001;
    
    irq_enable();

    return;
}

/*@}*/