freebsd-dev/sys/boot/i386/libi386/comconsole.c
Mike Smith 948486abe3 Initial integration of the i386 bootloader and BTX.
- Discard large amounts of BIOS-related code in favour of the more compact
   BTX vm86 interface.
 - Build the loader module as ELF, although the resulting object is a.out,
   make gensetdefs 32/64-bit sensitive and use a single copy of it.
 - Throw away installboot, as it's no longer required.
 - Use direct bcopy operations in the i386_copy module, as BTX
   maps the first 16M of memory.  Check operations against the
   detected size of actual memory.
1998-09-17 23:52:16 +00:00

104 lines
2.6 KiB
C

/*
* Copyright (c) 1998 Michael Smith (msmith@freebsd.org)
*
* 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.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``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 THE AUTHOR OR CONTRIBUTORS 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.
*
* From Id: probe_keyboard.c,v 1.13 1997/06/09 05:10:55 bde Exp
*
* $Id: comconsole.c,v 1.1.1.1 1998/08/21 03:17:41 msmith Exp $
*/
#include <stand.h>
#include <bootstrap.h>
#include <btxv86.h>
#include "libi386.h"
static void comc_probe(struct console *cp);
static int comc_init(int arg);
static void comc_putchar(int c);
static int comc_getchar(void);
static int comc_ischar(void);
struct console comconsole = {
"comconsole",
"BIOS serial port",
0,
comc_probe,
comc_init,
comc_putchar,
comc_getchar,
comc_ischar
};
#define BIOS_COMPORT 0
static void
comc_probe(struct console *cp)
{
/* XXX check the BIOS equipment list? */
cp->c_flags |= (C_PRESENTIN | C_PRESENTOUT);
}
static int
comc_init(int arg)
{
v86.ctl = V86_FLAGS;
v86.addr = 0x14;
v86.eax = 0xe3; /* 9600N81 */
v86.edx = BIOS_COMPORT; /* XXX take as arg, or use env var? */
v86int();
return(v86.efl & 1);
}
static void
comc_putchar(int c)
{
v86.ctl = 0;
v86.addr = 0x14;
v86.eax = 0x100 | c;
v86int();
}
static int
comc_getchar(void)
{
if (comc_ischar()) {
v86.ctl = 0;
v86.addr = 0x14;
v86.eax = 0x300;
v86int();
return(v86.eax);
} else {
return(-1);
}
}
static int
comc_ischar(void)
{
v86.ctl = 0;
v86.addr = 0x14;
v86.eax = 0x200;
v86int();
return(v86.eax & 0x1);
}