xref: /src/sys/arch/hp300/stand/common/clock.c

/*	$NetBSD: clock.c,v 1.11 2011/02/08 20:20:14 rmind Exp $	*/

/*
 * Copyright (c) 1988 University of Utah.
 * Copyright (c) 1982, 1990, 1993
 *	The Regents of the University of California.  All rights reserved.
 *
 * This code is derived from software contributed to Berkeley by
 * the Systems Programming Group of the University of Utah Computer
 * Science Department.
 *
 * 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.
 * 3. Neither the name of the University nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS 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 REGENTS 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: Utah $Hdr: clock.c 1.18 91/01/21$
 *
 *	@(#)clock.c	8.2 (Berkeley) 1/12/94
 */

#include <sys/param.h>

#include <net/if_ether.h>
#include <netinet/in.h>
#include <netinet/in_systm.h>

#include <hp300/stand/common/hilreg.h>

#include <lib/libsa/stand.h>
#include <lib/libsa/net.h>
#include <hp300/stand/common/samachdep.h>

#define FEBRUARY        2
#define STARTOFTIME     1970
#define SECDAY          (60L * 60L * 24L)
#define SECYR           (SECDAY * 365)

#define BBC_SET_REG     0xe0
#define BBC_WRITE_REG   0xc2
#define BBC_READ_REG    0xc3
#define NUM_BBC_REGS    12

#define leapyear(year)		((year) % 4 == 0)
#define range_test(n, l, h)	if ((n) < (l) || (n) > (h)) return 0
#define days_in_year(a)		(leapyear(a) ? 366 : 365)
#define days_in_month(a)	(month_days[(a) - 1])
#define bbc_to_decimal(a,b)	(bbc_registers[a] * 10 + bbc_registers[b])

static const int month_days[12] = {
	31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31
};

u_char bbc_registers[13];
struct hil_dev *bbcaddr = BBCADDR;

static int bbc_to_gmt(satime_t *);

satime_t
getsecs(void)
{
	static int bbcinited = 0;
	satime_t timbuf = 0;

	if (!bbc_to_gmt(&timbuf) && !bbcinited)
		printf("WARNING: bad date in battery clock\n");
	bbcinited = 1;

	/* Battery clock does not store usec's, so forget about it. */
	return timbuf;
}


static int
bbc_to_gmt(satime_t *timbuf)
{
	int i;
	u_long tmp;
	int year, month, day, hour, min, sec;

	read_bbc();

	sec = bbc_to_decimal(1, 0);
	min = bbc_to_decimal(3, 2);

	/*
	 * Hours are different for some reason. Makes no sense really.
	 */
	hour  = ((bbc_registers[5] & 0x03) * 10) + bbc_registers[4];
	day   = bbc_to_decimal(8, 7);
	month = bbc_to_decimal(10, 9);
	year  = bbc_to_decimal(12, 11) + 1900;
	if (year < STARTOFTIME)
		year += 100;

	range_test(hour, 0, 23);
	range_test(day, 1, 31);
	range_test(month, 1, 12);

	tmp = 0;

	for (i = STARTOFTIME; i < year; i++)
		tmp += days_in_year(i);
	if (leapyear(year) && month > FEBRUARY)
		tmp++;

	for (i = 1; i < month; i++)
	  	tmp += days_in_month(i);

	tmp += (day - 1);
	tmp = ((tmp * 24 + hour) * 60 + min) * 60 + sec;

	*timbuf = tmp;
	return 1;
}

void
read_bbc(void)
{
  	int i, read_okay;

	read_okay = 0;
	while (!read_okay) {
		read_okay = 1;
		for (i = 0; i <= NUM_BBC_REGS; i++)
			bbc_registers[i] = read_bbc_reg(i);
		for (i = 0; i <= NUM_BBC_REGS; i++)
			if (bbc_registers[i] != read_bbc_reg(i))
				read_okay = 0;
	}
}

u_char
read_bbc_reg(int reg)
{
	u_char data = reg;

	if (bbcaddr) {
#if 0
		send_hil_cmd(bbcaddr, BBC_SET_REG, &data, 1, NULL);
		send_hil_cmd(bbcaddr, BBC_READ_REG, NULL, 0, &data);
#else
		HILWAIT(bbcaddr);
		bbcaddr->hil_cmd = BBC_SET_REG;
		HILWAIT(bbcaddr);
		bbcaddr->hil_data = data;
		HILWAIT(bbcaddr);
		bbcaddr->hil_cmd = BBC_READ_REG;
		HILDATAWAIT(bbcaddr);
		data = bbcaddr->hil_data;
#endif
	}
	return data;
}