1999-12-29 09:54:46 +00:00
|
|
|
/*-
|
|
|
|
* Copyright (c) 1998 Michael Smith <msmith@freebsd.org>
|
|
|
|
* 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.
|
1998-09-17 23:52:16 +00:00
|
|
|
*/
|
|
|
|
|
2003-08-25 23:28:32 +00:00
|
|
|
#include <sys/cdefs.h>
|
|
|
|
__FBSDID("$FreeBSD$");
|
|
|
|
|
1998-09-17 23:52:16 +00:00
|
|
|
#include <stand.h>
|
|
|
|
#include <btxv86.h>
|
2000-08-03 09:14:02 +00:00
|
|
|
#include "bootstrap.h"
|
|
|
|
#include "libi386.h"
|
1998-09-17 23:52:16 +00:00
|
|
|
|
2008-06-16 17:04:04 +00:00
|
|
|
static int bios_seconds(void);
|
|
|
|
|
1998-09-17 23:52:16 +00:00
|
|
|
/*
|
2008-06-16 17:04:04 +00:00
|
|
|
* Return the BIOS time-of-day value.
|
1998-09-17 23:52:16 +00:00
|
|
|
*
|
|
|
|
* XXX uses undocumented BCD support from libstand.
|
|
|
|
*/
|
2008-06-16 17:04:04 +00:00
|
|
|
static int
|
|
|
|
bios_seconds(void)
|
1998-09-17 23:52:16 +00:00
|
|
|
{
|
2000-08-03 09:14:02 +00:00
|
|
|
int hr, minute, sec;
|
1998-09-17 23:52:16 +00:00
|
|
|
|
|
|
|
v86.ctl = 0;
|
|
|
|
v86.addr = 0x1a; /* int 0x1a, function 2 */
|
|
|
|
v86.eax = 0x0200;
|
|
|
|
v86int();
|
|
|
|
|
|
|
|
hr = bcd2bin((v86.ecx & 0xff00) >> 8); /* hour in %ch */
|
2000-08-03 09:14:02 +00:00
|
|
|
minute = bcd2bin(v86.ecx & 0xff); /* minute in %cl */
|
1998-09-17 23:52:16 +00:00
|
|
|
sec = bcd2bin((v86.edx & 0xff00) >> 8); /* second in %dh */
|
|
|
|
|
2008-06-16 17:04:04 +00:00
|
|
|
return (hr * 3600 + minute * 60 + sec);
|
|
|
|
}
|
|
|
|
|
|
|
|
/*
|
|
|
|
* Return the time in seconds since the beginning of the day.
|
|
|
|
*
|
|
|
|
* Some BIOSes (notably qemu) don't correctly read the RTC
|
|
|
|
* registers in an atomic way, sometimes returning bogus values.
|
|
|
|
* Therefore we "debounce" the reading by accepting it only when
|
|
|
|
* we got two identical values in succession.
|
|
|
|
*
|
|
|
|
* If we pass midnight, don't wrap back to 0.
|
|
|
|
*/
|
|
|
|
time_t
|
|
|
|
time(time_t *t)
|
|
|
|
{
|
|
|
|
static time_t lasttime;
|
|
|
|
time_t now, check;
|
|
|
|
int try;
|
|
|
|
|
|
|
|
try = 0;
|
|
|
|
check = bios_seconds();
|
|
|
|
do {
|
|
|
|
now = check;
|
|
|
|
check = bios_seconds();
|
|
|
|
} while (now != check && ++try < 1000);
|
|
|
|
|
1998-09-17 23:52:16 +00:00
|
|
|
if (now < lasttime)
|
|
|
|
now += 24 * 3600;
|
|
|
|
lasttime = now;
|
|
|
|
|
|
|
|
if (t != NULL)
|
|
|
|
*t = now;
|
|
|
|
return(now);
|
|
|
|
}
|
|
|
|
|
|
|
|
/*
|
|
|
|
* Use the BIOS Wait function to pause for (period) microseconds.
|
|
|
|
*
|
|
|
|
* Resolution of this function is variable, but typically around
|
|
|
|
* 1ms.
|
|
|
|
*/
|
|
|
|
void
|
|
|
|
delay(int period)
|
|
|
|
{
|
|
|
|
v86.ctl = 0;
|
1998-10-11 09:53:30 +00:00
|
|
|
v86.addr = 0x15; /* int 0x15, function 0x86 */
|
1998-09-17 23:52:16 +00:00
|
|
|
v86.eax = 0x8600;
|
|
|
|
v86.ecx = period >> 16;
|
|
|
|
v86.edx = period & 0xffff;
|
|
|
|
v86int();
|
|
|
|
}
|