NetBSD/sys/arch/i386/isa/ast.c

114 lines
2.3 KiB
C

/*
* Multi-port serial card interrupt demuxing support.
* Roland McGrath 3/20/94
* Charles Hannum 3/22/94
*
* $Id: ast.c,v 1.2 1994/03/23 03:01:50 mycroft Exp $
*/
#include "ast.h"
#include <sys/types.h>
#include <sys/device.h>
#include <machine/pio.h>
#include <i386/isa/isa_device.h>
int astprobe __P((struct isa_device *));
int astattach __P((struct isa_device *));
struct isa_driver astdriver = {
astprobe, astattach, "ast"
};
struct ast_softc {
struct device sc_dev;
u_short sc_iobase;
int sc_alive; /* Mask of slave units attached. */
int sc_slaves[8]; /* com device unit numbers. XXX - softc ptrs */
} ast_softc[NAST];
int
astprobe(dev)
struct isa_device *dev;
{
/*
* Do the normal com probe for the first UART and assume
* its presence means there is a multiport board there.
* XXX needs more robustness.
*/
return comprobe1(dev->id_iobase);
}
int
astattach(dev)
struct isa_device *dev;
{
struct ast_softc *sc = &ast_softc[dev->id_unit];
u_short iobase = dev->id_iobase;
unsigned int x;
/* XXX HACK */
sprintf(sc->sc_dev.dv_xname, "%s%d", astdriver.name, dev->id_unit);
sc->sc_dev.dv_unit = dev->id_unit;
sc->sc_iobase = iobase;
/*
* Enable the master interrupt.
*/
outb(iobase | 0x1f, 0x80);
x = inb(iobase | 0x1f);
/*
* My guess is this bitmask tells you how many ports are there.
* I only have a 4-port board to try (returns 0xf). --roland
*
* It's also not clear that it would be correct to rely on this, since
* there might be an interrupt pending on one of the ports, and thus
* its bit wouldn't be set. - mycroft
*/
printf("%s: 0x%x\n", sc->sc_dev.dv_xname, x);
}
void
astslave(dev)
struct isa_device *dev;
{
struct ast_softc *sc = &ast_softc[dev->id_parent->id_unit];
sc->sc_slaves[dev->id_physid] = dev->id_unit;
sc->sc_alive |= 1 << dev->id_physid;
}
int
astintr(unit)
int unit;
{
struct ast_softc *sc = &ast_softc[unit];
u_short iobase = sc->sc_iobase;
int alive = sc->sc_alive;
int bits;
bits = inb(iobase | 0x1f) & alive;
if (bits == alive)
return 0;
do {
#define TRY(n) \
if ((bits & (1 << (n))) == 0) \
comintr(sc->sc_slaves[n]); /* XXX softc ptr */
TRY(0);
TRY(1);
TRY(2);
TRY(3);
TRY(4);
TRY(5);
TRY(6);
TRY(7);
bits = inb(iobase | 0x1f) & alive;
} while (bits != alive);
return 1;
}