1/*-
2 * Copyright (c) 1998 Michael Smith <msmith@freebsd.org>
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 * notice, this list of conditions and the following disclaimer in the
12 * documentation and/or other materials provided with the distribution.
13 *
14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24 * SUCH DAMAGE.
25 */
26
27#include <sys/cdefs.h>
28__FBSDID("$FreeBSD: head/sys/boot/pc98/libpc98/time.c 119880 2003-09-08 09:11:32Z obrien $");
29
30#include <stand.h>
31#include <btxv86.h>
32#ifdef PC98
33#include <machine/cpufunc.h>
34#endif
35#include "bootstrap.h"
36#include "libi386.h"
37
38/*
39 * Return the time in seconds since the beginning of the day.
40 *
41 * If we pass midnight, don't wrap back to 0.
42 *
43 * XXX uses undocumented BCD support from libstand.
44 */
45
46time_t
47time(time_t *t)
48{
49 static time_t lasttime, now;
50 int hr, minute, sec;
51
52#ifdef PC98
53 unsigned char bios_time[6];
54#endif
55
56 v86.ctl = 0;
57#ifdef PC98
58 v86.addr = 0x1c; /* int 0x1c, function 0 */
59 v86.eax = 0x0000;
60 v86.es = VTOPSEG(bios_time);
61 v86.ebx = VTOPOFF(bios_time);
62#else
63 v86.addr = 0x1a; /* int 0x1a, function 2 */
64 v86.eax = 0x0200;
65#endif
66 v86int();
67
68#ifdef PC98
69 hr = bcd2bin(bios_time[3]);
70 minute = bcd2bin(bios_time[4]);
71 sec = bcd2bin(bios_time[5]);
72#else
73 hr = bcd2bin((v86.ecx & 0xff00) >> 8); /* hour in %ch */
74 minute = bcd2bin(v86.ecx & 0xff); /* minute in %cl */
75 sec = bcd2bin((v86.edx & 0xff00) >> 8); /* second in %dh */
76#endif
77
78 now = hr * 3600 + minute * 60 + sec;
79 if (now < lasttime)
80 now += 24 * 3600;
81 lasttime = now;
82
83 if (t != NULL)
84 *t = now;
85 return(now);
86}
87
88/*
89 * Use the BIOS Wait function to pause for (period) microseconds.
90 *
91 * Resolution of this function is variable, but typically around
92 * 1ms.
93 */
94void
95delay(int period)
96{
97#ifdef PC98
98 int i;
99 period = (period + 500) / 1000;
100 for( ; period != 0 ; period--)
101 for(i=800;i != 0; i--)
102 outb(0x5f,0); /* wait 600ns */
103#else
104 v86.ctl = 0;
105 v86.addr = 0x15; /* int 0x15, function 0x86 */
106 v86.eax = 0x8600;
107 v86.ecx = period >> 16;
108 v86.edx = period & 0xffff;
109 v86int();
110#endif
111}