3644d8c222
git-svn-id: https://svn.code.sf.net/p/freedos/svn/kernel/trunk@345 6ac86273-5f31-0410-b378-82cca8765d1b
355 lines
10 KiB
C
355 lines
10 KiB
C
/****************************************************************/
|
|
/* */
|
|
/* sysclk.c */
|
|
/* */
|
|
/* System Clock Driver */
|
|
/* */
|
|
/* Copyright (c) 1995 */
|
|
/* Pasquale J. Villani */
|
|
/* All Rights Reserved */
|
|
/* */
|
|
/* This file is part of DOS-C. */
|
|
/* */
|
|
/* DOS-C is free software; you can redistribute it and/or */
|
|
/* modify it under the terms of the GNU General Public License */
|
|
/* as published by the Free Software Foundation; either version */
|
|
/* 2, or (at your option) any later version. */
|
|
/* */
|
|
/* DOS-C is distributed in the hope that it will be useful, but */
|
|
/* WITHOUT ANY WARRANTY; without even the implied warranty of */
|
|
/* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See */
|
|
/* the GNU General Public License for more details. */
|
|
/* */
|
|
/* You should have received a copy of the GNU General Public */
|
|
/* License along with DOS-C; see the file COPYING. If not, */
|
|
/* write to the Free Software Foundation, 675 Mass Ave, */
|
|
/* Cambridge, MA 02139, USA. */
|
|
/****************************************************************/
|
|
|
|
#include "portab.h"
|
|
#include "globals.h"
|
|
|
|
#ifdef VERSION_STRINGS
|
|
static BYTE *RcsId =
|
|
"$Id$";
|
|
#endif
|
|
|
|
#ifdef PROTO
|
|
VOID ASMCFUNC WriteATClock(BYTE *, BYTE, BYTE, BYTE);
|
|
VOID ASMCFUNC WritePCClock(ULONG);
|
|
COUNT BcdToByte(COUNT);
|
|
COUNT BcdToWord(BYTE *, UWORD *, UWORD *, UWORD *);
|
|
COUNT ByteToBcd(COUNT);
|
|
VOID DayToBcd(BYTE *, UWORD *, UWORD *, UWORD *);
|
|
#else
|
|
VOID WriteATClock();
|
|
VOID WritePCClock();
|
|
COUNT BcdToByte();
|
|
COUNT BcdToWord();
|
|
COUNT ByteToBcd();
|
|
VOID DayToBcd();
|
|
#endif
|
|
|
|
/* */
|
|
/* WARNING - THIS DRIVER IS NON-PORTABLE!!!! */
|
|
/* */
|
|
extern UWORD days[2][13]; /* this is defined by SYSTIME.C */
|
|
|
|
static struct ClockRecord clk;
|
|
|
|
/*
|
|
static BYTE bcdDays[4];
|
|
static UWORD Month,
|
|
Day,
|
|
Year;
|
|
static BYTE bcdMinutes;
|
|
static BYTE bcdHours;
|
|
/ ** static BYTE bcdHundredths;* /
|
|
static BYTE bcdSeconds;
|
|
|
|
static ULONG Ticks;
|
|
*/
|
|
UWORD ASM DaysSinceEpoch = 0;
|
|
|
|
BOOL ASMCFUNC ReadATClock(BYTE *, BYTE *, BYTE *, BYTE *);
|
|
|
|
STATIC COUNT BcdToByte(COUNT x)
|
|
{
|
|
return ((((x) >> 4) & 0xf) * 10 + ((x) & 0xf));
|
|
}
|
|
|
|
WORD ASMCFUNC FAR clk_driver(rqptr rp)
|
|
{
|
|
COUNT c;
|
|
const UWORD *pdays;
|
|
BYTE bcd_days[4], bcd_minutes, bcd_hours, bcd_seconds;
|
|
ULONG Ticks;
|
|
UWORD Month, Day, Year;
|
|
|
|
switch (rp->r_command)
|
|
{
|
|
case C_INIT:
|
|
/* If AT clock exists, copy AT clock time to system clock */
|
|
if (!ReadATClock(bcd_days, &bcd_hours, &bcd_minutes, &bcd_seconds))
|
|
{
|
|
DaysSinceEpoch =
|
|
DaysFromYearMonthDay(100 * BcdToByte(bcd_days[3]) +
|
|
BcdToByte(bcd_days[2]),
|
|
BcdToByte(bcd_days[1]),
|
|
BcdToByte(bcd_days[0]));
|
|
|
|
/*
|
|
* This is a rather tricky calculation. The number of timer ticks per
|
|
* second is not exactly 18.2, but rather 0x1800b0 / 86400 = 19663 / 1080
|
|
* (the timer interrupt updates the midnight flag when the tick count
|
|
* reaches 0x1800b0). Fortunately, 86400 * 19663 = 1698883200 < ULONG_MAX,
|
|
* so we can simply multiply the number of seconds by 19663 without
|
|
* worrying about overflow. :) -- ror4
|
|
*/
|
|
Ticks = (3600ul * BcdToByte(bcd_hours) +
|
|
60ul * BcdToByte(bcd_minutes) +
|
|
BcdToByte(bcd_seconds)) * 19663ul / 1080ul;
|
|
WritePCClock(Ticks);
|
|
}
|
|
/* rp->r_endaddr = device_end(); not needed - bart */
|
|
rp->r_nunits = 0;
|
|
return S_DONE;
|
|
|
|
case C_INPUT:
|
|
{
|
|
ULONG remainder, hs;
|
|
ReadPCClock(&Ticks);
|
|
clk.clkDays = DaysSinceEpoch;
|
|
/*
|
|
* Another tricky calculation (after the one in `main.c'). This time
|
|
* we do have a problem with overflow, because we need to extract the
|
|
* 1/100s portion too. The scaling factor is now
|
|
* (100 x 86400) / 0x1800b0 = 108000 / 19663. -- ror4
|
|
*/
|
|
hs = 0;
|
|
#if 0
|
|
if (Ticks >= 64 * 19663ul)
|
|
{
|
|
hs += 64 * 108000ul;
|
|
Ticks -= 64 * 19663ul;
|
|
}
|
|
if (Ticks >= 32 * 19663ul)
|
|
{
|
|
hs += 32 * 108000ul;
|
|
Ticks -= 32 * 19663ul;
|
|
}
|
|
if (Ticks >= 16 * 19663ul)
|
|
{
|
|
hs += 16 * 108000ul;
|
|
Ticks -= 16 * 19663ul;
|
|
}
|
|
if (Ticks >= 8 * 19663ul)
|
|
{
|
|
hs += 8 * 108000ul;
|
|
Ticks -= 8 * 19663ul;
|
|
}
|
|
if (Ticks >= 4 * 19663ul)
|
|
{
|
|
hs += 4 * 108000ul;
|
|
Ticks -= 4 * 19663ul;
|
|
}
|
|
if (Ticks >= 2 * 19663ul)
|
|
{
|
|
hs += 2 * 108000ul;
|
|
Ticks -= 2 * 19663ul;
|
|
}
|
|
if (Ticks >= 19663ul)
|
|
{
|
|
hs += 108000ul;
|
|
Ticks -= 19663ul;
|
|
}
|
|
#else
|
|
{
|
|
UWORD q1 = Ticks / 19663ul;
|
|
|
|
Ticks -= q1 * 19663ul;
|
|
hs = q1 * 108000ul;
|
|
}
|
|
|
|
#endif
|
|
/*
|
|
* Now Ticks < 19663, so Ticks * 108000 < 2123604000 < ULONG_MAX.
|
|
* *phew* -- ror4
|
|
*/
|
|
hs += Ticks * 108000ul / 19663ul;
|
|
clk.clkHours = hs / 360000ul;
|
|
remainder = hs % 360000ul;
|
|
clk.clkMinutes = remainder / 6000ul;
|
|
remainder %= 6000ul;
|
|
clk.clkSeconds = remainder / 100ul;
|
|
clk.clkHundredths = remainder % 100ul;
|
|
}
|
|
|
|
fmemcpy(rp->r_trans, &clk,
|
|
min(sizeof(struct ClockRecord), rp->r_count));
|
|
return S_DONE;
|
|
|
|
case C_OUTPUT:
|
|
rp->r_count = min(rp->r_count, sizeof(struct ClockRecord));
|
|
fmemcpy(&clk, rp->r_trans, rp->r_count);
|
|
|
|
/* Set PC Clock first */
|
|
DaysSinceEpoch = clk.clkDays;
|
|
{
|
|
ULONG hs;
|
|
hs = 360000ul * clk.clkHours +
|
|
6000ul * clk.clkMinutes +
|
|
100ul * clk.clkSeconds + clk.clkHundredths;
|
|
Ticks = 0;
|
|
#if 0
|
|
if (hs >= 64 * 108000ul)
|
|
{
|
|
Ticks += 64 * 19663ul;
|
|
hs -= 64 * 108000ul;
|
|
}
|
|
if (hs >= 32 * 108000ul)
|
|
{
|
|
Ticks += 32 * 19663ul;
|
|
hs -= 32 * 108000ul;
|
|
}
|
|
if (hs >= 16 * 108000ul)
|
|
{
|
|
Ticks += 16 * 19663ul;
|
|
hs -= 16 * 108000ul;
|
|
}
|
|
if (hs >= 8 * 108000ul)
|
|
{
|
|
Ticks += 8 * 19663ul;
|
|
hs -= 8 * 108000ul;
|
|
}
|
|
if (hs >= 4 * 108000ul)
|
|
{
|
|
Ticks += 4 * 19663ul;
|
|
hs -= 4 * 108000ul;
|
|
}
|
|
if (hs >= 2 * 108000ul)
|
|
{
|
|
Ticks += 2 * 19663ul;
|
|
hs -= 2 * 108000ul;
|
|
}
|
|
if (hs >= 108000ul)
|
|
{
|
|
Ticks += 19663ul;
|
|
hs -= 108000ul;
|
|
}
|
|
#else
|
|
{
|
|
UWORD q1 = hs / 108000ul;
|
|
|
|
hs -= q1 * 108000ul;
|
|
Ticks = q1 * 19663ul;
|
|
}
|
|
|
|
#endif
|
|
Ticks += hs * 19663ul / 108000ul;
|
|
}
|
|
WritePCClock(Ticks);
|
|
|
|
/* Now set AT clock */
|
|
/* Fix year by looping through each year, subtracting */
|
|
/* the appropriate number of days for that year. */
|
|
for (Year = 1980, c = clk.clkDays;;)
|
|
{
|
|
pdays = is_leap_year_monthdays(Year);
|
|
if (c >= pdays[12])
|
|
{
|
|
++Year;
|
|
c -= pdays[12];
|
|
}
|
|
else
|
|
break;
|
|
}
|
|
|
|
/* c contains the days left and count the number of */
|
|
/* days for that year. Use this to index the table. */
|
|
for (Month = 1; Month < 13; ++Month)
|
|
{
|
|
if (pdays[Month] > c)
|
|
{
|
|
Day = c - pdays[Month - 1] + 1;
|
|
break;
|
|
}
|
|
}
|
|
|
|
DayToBcd((BYTE *) bcd_days, &Month, &Day, &Year);
|
|
bcd_minutes = ByteToBcd(clk.clkMinutes);
|
|
bcd_hours = ByteToBcd(clk.clkHours);
|
|
bcd_seconds = ByteToBcd(clk.clkSeconds);
|
|
WriteATClock(bcd_days, bcd_hours, bcd_minutes, bcd_seconds);
|
|
return S_DONE;
|
|
|
|
case C_OFLUSH:
|
|
case C_IFLUSH:
|
|
return S_DONE;
|
|
|
|
case C_OUB:
|
|
case C_NDREAD:
|
|
case C_OSTAT:
|
|
case C_ISTAT:
|
|
default:
|
|
return failure(E_FAILURE); /* general failure */
|
|
}
|
|
}
|
|
|
|
COUNT ByteToBcd(COUNT x)
|
|
{
|
|
return ((x / 10) << 4) | (x % 10);
|
|
}
|
|
|
|
VOID DayToBcd(BYTE * x, UWORD * mon, UWORD * day, UWORD * yr)
|
|
{
|
|
x[1] = ByteToBcd(*mon);
|
|
x[0] = ByteToBcd(*day);
|
|
x[3] = ByteToBcd(*yr / 100);
|
|
x[2] = ByteToBcd(*yr % 100);
|
|
}
|
|
|
|
/*
|
|
* Log: sysclk.c,v - for newer entries do "cvs log sysclk.c"
|
|
*
|
|
* Revision 1.3 2000/03/09 06:07:11 kernel
|
|
* 2017f updates by James Tabor
|
|
*
|
|
* Revision 1.2 1999/04/12 03:21:17 jprice
|
|
* more ror4 patches. Changes for multi-block IO
|
|
*
|
|
* Revision 1.1.1.1 1999/03/29 15:41:33 jprice
|
|
* New version without IPL.SYS
|
|
*
|
|
* Revision 1.5 1999/02/08 05:55:58 jprice
|
|
* Added Pat's 1937 kernel patches
|
|
*
|
|
* Revision 1.4 1999/02/04 03:14:07 jprice
|
|
* Formating. Added comments.
|
|
*
|
|
* Revision 1.3 1999/02/01 01:48:41 jprice
|
|
* Clean up; Now you can use hex numbers in config.sys. added config.sys screen function to change screen mode (28 or 43/50 lines)
|
|
*
|
|
* Revision 1.2 1999/01/22 04:13:27 jprice
|
|
* Formating
|
|
*
|
|
* Revision 1.1.1.1 1999/01/20 05:51:01 jprice
|
|
* Imported sources
|
|
*
|
|
*
|
|
* Rev 1.4 04 Jan 1998 23:15:16 patv
|
|
* Changed Log for strip utility
|
|
*
|
|
* Rev 1.3 29 May 1996 21:03:48 patv
|
|
* bug fixes for v0.91a
|
|
*
|
|
* Rev 1.2 19 Feb 1996 3:21:34 patv
|
|
* Added NLS, int2f and config.sys processing
|
|
*
|
|
* Rev 1.1 01 Sep 1995 17:54:18 patv
|
|
* First GPL release.
|
|
*
|
|
* Rev 1.0 02 Jul 1995 8:32:30 patv
|
|
* Initial revision.
|
|
*/
|