/* functions for the 8259 pic. test */

#include <std.h>
#include "mult.h"


/* external variables */

int int0(),int1(),int2(),int3(),int4(),int5(),int6(),int7();

char inted = 0;		/* 1 if int occured */
char intnum = 0;	/* interrupt number left here after int occurs */
char level = 'y';	/* level or edge triggered */
char addint = 's';	/* address interval */
char single =  'y';	/* single or multiple */
char icw4 = 'y';	/* icw4 needed */
char fulnst = 'n';	/* fully nested mode */
char buffed = 'y';	/* buffered or sp/en mode */
char ms = 'm';		/* master/slave */
char aeoi = 'n';	/* automatic end of interrupt */

unsigned char jtable[128] = 0;	/* jump table */
unsigned char *addr = 0;	/* 32 byte boundry address */

inttest()

{
	error = inttest;	/* setup error for loop */
	disab();		/* disable interrupts */
	jumploc();		/* setup the jump table */

	icw4 = 'y';		/* to send icw4 */
	buffed = 'y';		/* to enable buffered mode */

	intint();		/* initialize interrupt chip */
	intset();		/* setup all interrupts to occur */
	intwait();		/* wait for all interrupts and check isr */
}

eoi()		/* end of int */

{
	out(TBASE+4,0x20);
}

intint()	/* initialize interrupter */

{
	int icw1,icw2,ocw1;

	out(TBASE+7,0x08);	/* select group and allow int to occur */
	icw1 = (unsigned)(addr) & 0xe0;	/* mask off 5 lsbs */

	if(icw4 == 'y')		/* is icw4 needed */
		icw1 |= 1;	/* set bit 0 high */

	if(single == 'y')	/* is this the only pic */
		icw1 |= 2;	/* set bit 1 high */

	if(addint == 's')	/* short or long interval */
		icw1 |= 4;	/* set bit 2 high */

	if(level == 'y')	/* level triggered */
		icw1 |= 8;	/* set bit 3 high */

	icw1 |= 0x10;		/* set bit 4 high for icw1 */

	icw2 = (unsigned)(addr) >> 8;	/* set up icw2 */

	out(TBASE+4,icw1);	/* issue first icw */
	out(TBASE+5,icw2);	/* issue second icw */

	if(icw4 == 'y')		/* send icw4 if needed */
	 	nicw4();

	ocw1 = 0xff;		/* mask off all interrupts */
	out(TBASE+5,ocw1);	/* issue first ocw */
}


nicw4()		/* output icw4 to pic. */

{
	int ic4;

	ic4 = 0;		/* clear icw4 */

	if(aeoi == 'y')		/* if automatic end of int then */
		ic4 |= 2;	/* set bit 1 high */
	if(buffed == 'y')	/* if in buffered mode */
	{
		ic4 |= 8;	/* set bit 3 high if so (mult/io won't work */
				/* if it isn't buffered) */
 		if(ms == 'm')	/* if master set bit 2 high */
			ic4 |= 4;
	}

	if(fulnst == 'y')	/* is it fully nested mode */
		ic4 |= 0x10;	/* set bit 4 high */

	out(TBASE+5,ic4);	/* output icw4 to pic */

}


jumploc()	/* locate the 32 byte boundry in the array jtable */

{
	int i;
	int routine[8];
	unsigned char *rout;

	routine[0] = int0;	/* load int0 addr in routine[0] */

	routine[1] = int1;	/* load int1 addr in routine[1] */

	routine[2] = int2;	/* load int2 addr in routine[2] */

	routine[3] = int3;	/* load int3 addr in routine[3] */

	routine[4] = int4;	/* load int4 addr in routine[4] */

	routine[5] = int5;	/* load int5 addr in routine[5] */

	routine[6] = int6;	/* load int6 addr in routine[6] */

	routine[7] = int7;	/* load int7 addr in routine[7] */

	addr = (unsigned)(jtable) & 0x3f;	/* check for 32 byte bound */
	if(addr == 0x20)
		addr = jtable;
	else
	 	addr = ((unsigned)(jtable) & ~0x1f) + 0x20; /* force it */

	for( i = 0 ; i < 8 ; ++i)
	{
		rout = addr +(i * 4);
		*rout = 0xc3;	/* jump machine code */
		*(rout+1) = routine[i] & 0xff;	/* low addr of jump */
		*(rout+2) = routine[i] >> 8;	/* high addr of jump */
	}

}

intwait()		/* loops in wait for int 10000 times */

{
	int a,i,j;

	out(TBASE+5,0);		/* allow all interrupts to occur */
	eoi();		/* send an end of interrupt to clear the pic */

	putcnw('\n');	/* for spacing on the first int */

	for( j = 0 ; j < 8 ; ++j)
	{
		inted = 0;	/* reset interrupted flag */

		enab();		/* enable interrupts */

		for( i=0; i < 10000; ++i)
		{
			if(inted == 1)
				break;
		}
	

		disab();	/* disable interrupts */

		if(inted == 0)
		{
			puts("test was not interrupted during int #");	
			putdec(j);
			putc('\n');
			terflg();
		}


		else if((a = girs()) == 0xff)	/* get the in service reg */
		{
			puts("their was no int in service during int #");
			putdec(j);
			putc('\n');
			terflg();
		}

		else if(a != intnum)
		{
			puts("failed the interrupt test the in ");
			puts("service register had ");
			putdec(a);
			puts("\nwhen the int level was ");
			putdec(intnum);
			putc('\n');
			terflg();
		}

		else
		{
			puts("interrupt level #");
			putdec(j);
			puts(" occured\n");
		}

		setmask();	/* calculate the new mask */
		eoi();		/* send end of int */

	}
	if(erflg == 0 && verflg == 0)
		puts("passes interrupt test!\n");
}

setmask()	/* setup int mask for next lower priority */

{
	int a;

	a = in(TBASE+5);	/* input int mask */
	a = a * 2 + 1;		/* multiply by two and add 1 */
	out(TBASE+5,a);		/* output new mask */
}

girs()		/* get the isr data */

{
	int a,b,c,i;
	out(TBASE+4,0x0b);	/* send out ocw3 */
	a = in(TBASE+4);	/* input isr */

	c = 0xff;		/* will still be this if no isr */
	for(i=0; i<8 ; ++i)
	{
		b = (a >> i) & 1;	/* b equals one bit in a */
		if(b == 1)
		{
			c = i;		/* c equals the bit # */
			break;
		}

	}
	return(c);	/* return the int # */
}
		

intset()	/* setup all interrupts to occur */

{
	int i;

	threint = 'y';		/* set interrupts on thre all groups */

	base = TBASE;		/* set base to test board */
	for(i=1; i<4; ++i)
	{
		group = i;	/* set group to i */
		groupsel();	/* select the group */

		setint();	/* set up ace to interrupt on thre */
	}

	out(TBASE+7,08);	/* allow interrupts to occur */
 
	out(SBASE+7,0x20);	/* select group 0 with printer ports enabled */
	out(SBASE+1,0xbf);	/* set bit 5 of port 1 low */
	out(SBASE,0x1f);	/* set the 3 msb of port 0 low */
	/* the clock should always be interrupting */
}