freebsd-dev/sys/boot/i386/libi386/vidconsole.c
Mike Smith c2f9d95de5 This is the new unified bootstrap, sometimes known previously as the
'three-stage' bootstrap.
There are a number of caveats with the code in its current state:
 - The i386 bootstrap only supports booting from a floppy.
 - The kernel and kld do not yet know how to deal with the extended
   information and module summary passed in.
 - PnP-based autodetection and demand loading of modules is not implemented.
 - i386 ELF kernel loading is not ready yet.
 - The i386 bootstrap is loaded via an ugly blockmap.

On the alpha, both net- and disk-booting (SRM console machines only) is
supported.  No blockmaps are used by this code.

Obtained from:	Parts from the NetBSD/i386 standalone bootstrap.
1998-08-21 03:17:42 +00:00

200 lines
5.1 KiB
C

/*
* Copyright (c) 1998 Michael Smith (msmith@freebsd.org)
* Copyright (c) 1997 Kazutaka YOKOTA (yokota@zodiac.mech.utsunomiya-u.ac.jp)
* 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.
*
* 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
*
* $Id$
*/
#include <stand.h>
#include <machine/cpufunc.h>
#include "bootstrap.h"
/* in vidconsole.S */
extern void vidputc(int c);
extern int kbdgetc(void);
extern int kbdiskey(void);
static int probe_keyboard(void);
static void vidc_probe(struct console *cp);
static int vidc_init(int arg);
static int vidc_in(void);
struct console vidconsole = {
"vidconsole",
"internal video/keyboard",
0,
vidc_probe,
vidc_init,
vidputc,
vidc_in,
kbdiskey
};
static void
vidc_probe(struct console *cp)
{
/* look for a keyboard */
#if 0
if (probe_keyboard()) {
#else
if (1) {
#endif
cp->c_flags |= C_PRESENTIN;
}
/* XXX for now, always assume we can do BIOS screen output */
cp->c_flags |= C_PRESENTOUT;
}
static int
vidc_init(int arg)
{
return(0); /* XXX reinit? */
}
static int
vidc_in(void)
{
if (kbdiskey()) {
return(kbdgetc());
} else {
return(-1);
}
}
#define PROBE_MAXRETRY 5
#define PROBE_MAXWAIT 400
#define IO_DUMMY 0x84
#define IO_KBD 0x060 /* 8042 Keyboard */
/* selected defines from kbdio.h */
#define KBD_STATUS_PORT 4 /* status port, read */
#define KBD_DATA_PORT 0 /* data port, read/write
* also used as keyboard command
* and mouse command port
*/
#define KBDC_ECHO 0x00ee
#define KBDS_ANY_BUFFER_FULL 0x0001
#define KBDS_INPUT_BUFFER_FULL 0x0002
#define KBD_ECHO 0x00ee
/* 7 microsec delay necessary for some keyboard controllers */
static void
delay7(void)
{
/*
* I know this is broken, but no timer is avaiable yet at this stage...
* See also comments in `delay1ms()'.
*/
inb(IO_DUMMY); inb(IO_DUMMY);
inb(IO_DUMMY); inb(IO_DUMMY);
inb(IO_DUMMY); inb(IO_DUMMY);
}
/*
* This routine uses an inb to an unused port, the time to execute that
* inb is approximately 1.25uS. This value is pretty constant across
* all CPU's and all buses, with the exception of some PCI implentations
* that do not forward this I/O adress to the ISA bus as they know it
* is not a valid ISA bus address, those machines execute this inb in
* 60 nS :-(.
*
*/
static void
delay1ms(void)
{
int i = 800;
while (--i >= 0)
(void)inb(0x84);
}
/*
* We use the presence/absence of a keyboard to determine whether the internal
* console can be used for input.
*
* Perform a simple test on the keyboard; issue the ECHO command and see
* if the right answer is returned. We don't do anything as drastic as
* full keyboard reset; it will be too troublesome and take too much time.
*/
static int
probe_keyboard(void)
{
int retry = PROBE_MAXRETRY;
int wait;
int i;
while (--retry >= 0) {
/* flush any noise */
while (inb(IO_KBD + KBD_STATUS_PORT) & KBDS_ANY_BUFFER_FULL) {
delay7();
inb(IO_KBD + KBD_DATA_PORT);
delay1ms();
}
/* wait until the controller can accept a command */
for (wait = PROBE_MAXWAIT; wait > 0; --wait) {
if (((i = inb(IO_KBD + KBD_STATUS_PORT))
& (KBDS_INPUT_BUFFER_FULL | KBDS_ANY_BUFFER_FULL)) == 0)
break;
if (i & KBDS_ANY_BUFFER_FULL) {
delay7();
inb(IO_KBD + KBD_DATA_PORT);
}
delay1ms();
}
if (wait <= 0)
continue;
/* send the ECHO command */
outb(IO_KBD + KBD_DATA_PORT, KBDC_ECHO);
/* wait for a response */
for (wait = PROBE_MAXWAIT; wait > 0; --wait) {
if (inb(IO_KBD + KBD_STATUS_PORT) & KBDS_ANY_BUFFER_FULL)
break;
delay1ms();
}
if (wait <= 0)
continue;
delay7();
i = inb(IO_KBD + KBD_DATA_PORT);
#ifdef PROBE_KBD_BEBUG
printf("probe_keyboard: got 0x%x.\n", i);
#endif
if (i == KBD_ECHO) {
/* got the right answer */
return (0);
}
}
return (1);
}