NetBSD/sys/arch/pc532/stand/scn.c

104 lines
2.9 KiB
C

/* $NetBSD: scn.c,v 1.3 1995/08/29 21:55:49 phil Exp $ */
/*-
* Copyright (c) 1994 Philip L. Budne.
* All rights reserved.
*
* 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. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by Philip L. Budne.
* 4. The name of Philip L. Budne may not be used to endorse or promote
* products derived from this software without specific prior written
* permission.
*
* THIS SOFTWARE IS PROVIDED BY PHILIP BUDNE ``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 PHILIP BUDNE 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.
*/
/*
* scn.c -- scn2681/2692/68881 standalone console driver
* Phil Budne, May 10, 1994
*
*/
#ifdef SCNCONSOLE
#include <sys/types.h>
#include <dev/cons.h>
#define DUART 0x28000000
/* registers */
#define SCN_STAT 1
#define SCN_DATA 3
/* status bits */
#define STAT_RXRDY 0x01
#define STAT_TXRDY 0x04
#ifndef SCNCNUNIT
#define SCNCNUNIT 0
#endif
unsigned char * volatile scncnaddr = (unsigned char *) DUART + 8 * SCNCNUNIT;
scnprobe(cp)
struct consdev *cp;
{
/* the only game in town */
cp->cn_pri = CN_NORMAL; /* XXX remote? */
}
scninit(cp)
struct consdev *cp;
{
/* leave things they way the PROM set them */
}
scngetchar(cp)
struct consdev *cp;
{
register unsigned char * volatile scn = scncnaddr;
if ((scn[SCN_STAT] & STAT_RXRDY) == 0)
return(0);
return scn[SCN_DATA];
}
scnputchar(cp, c)
struct consdev *cp;
register int c;
{
register unsigned char * volatile scn = scncnaddr;
register int timo;
short stat;
/* wait a reasonable time for the transmitter to come ready */
timo = 50000;
while (((stat = scn[SCN_STAT]) & STAT_TXRDY) == 0 && --timo)
;
scn[SCN_DATA] = c;
#if 0
/* wait for this transmission to complete */
timo = 1000000;
while (((stat = scn[SCN_STAT]) & STAT_TXRDY) == 0 && --timo)
;
#endif
}
#endif