gbasys

diff src/intr.c @ 0:875ef6085efc

gbasys mercurial repository
author John Tsiombikas <nuclear@member.fsf.org>
date Sun, 04 Mar 2012 04:04:25 +0200
parents
children 72c6429ae953 047c61960005
line diff
     1.1 --- /dev/null	Thu Jan 01 00:00:00 1970 +0000
     1.2 +++ b/src/intr.c	Sun Mar 04 04:04:25 2012 +0200
     1.3 @@ -0,0 +1,70 @@
     1.4 +/*
     1.5 +Copyright 2004 John Tsiombikas <nuclear@siggraph.org>
     1.6 +
     1.7 +This file is part of libgba, a library for GameBoy Advance development.
     1.8 +
     1.9 +This program is free software; you can redistribute it and/or modify
    1.10 +it under the terms of the GNU General Public License as published by
    1.11 +the Free Software Foundation; either version 2 of the License, or
    1.12 +(at your option) any later version.
    1.13 +
    1.14 +This program is distributed in the hope that it will be useful,
    1.15 +but WITHOUT ANY WARRANTY; without even the implied warranty of
    1.16 +MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    1.17 +GNU General Public License for more details.
    1.18 +
    1.19 +You should have received a copy of the GNU General Public License
    1.20 +along with this program; if not, write to the Free Software
    1.21 +Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
    1.22 +*/
    1.23 +
    1.24 +#include "intr.h"
    1.25 +#include "error.h"
    1.26 +
    1.27 +#include "gfx.h"
    1.28 +
    1.29 +unsigned short *reg_int_master = (unsigned short*)0x04000208;
    1.30 +unsigned short *reg_int_mask = (unsigned short*)0x04000200;
    1.31 +static volatile unsigned short *reg_int = (unsigned short*)0x04000202;
    1.32 +
    1.33 +#define MAX_INTR	14
    1.34 +static void (*intr_table[MAX_INTR])(void);
    1.35 +
    1.36 +static void unexpected_intr(void) {
    1.37 +	panic("unexpected interrupt");
    1.38 +}
    1.39 +
    1.40 +static void intr_handler(void) {
    1.41 +	int i;
    1.42 +	unsigned short irq;
    1.43 +	char buf[20];
    1.44 +	
    1.45 +	clr_int();
    1.46 +
    1.47 +	irq = *reg_int & 0x3fff;
    1.48 +
    1.49 +	for(i=0; i<MAX_INTR; i++) {
    1.50 +		unsigned short irq_bit = (1 << i);
    1.51 +		if((irq & irq_bit) && intr_table[i]) {
    1.52 +			intr_table[i]();
    1.53 +		}
    1.54 +	}
    1.55 +
    1.56 +	*reg_int = irq;
    1.57 +
    1.58 +	set_int();
    1.59 +}
    1.60 +
    1.61 +void intr_init(void) {
    1.62 +	int i;
    1.63 +	unsigned long *ptr = (unsigned long*)0x3007ffc;
    1.64 +	*ptr = (unsigned long)intr_handler;
    1.65 +
    1.66 +	for(i=0; i<MAX_INTR; i++) {
    1.67 +		interrupt(i, unexpected_intr);
    1.68 +	}
    1.69 +}
    1.70 +
    1.71 +void interrupt(int intr, void (*handler)(void)) {
    1.72 +	intr_table[intr] = handler;
    1.73 +}