* Copyright (c) 1988 University of Utah.

/* $NetBSD: clock.c,v 1.15 2025/05/17 17:27:21 tsutsui 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 <hp300/dev/frodoreg.h> /* for APCI offsets */
#include <hp300/dev/intioreg.h> /* for frodo offsets */
#include <dev/ic/mc146818reg.h>
#include <dev/clock_subr.h>

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

#define FEBRUARY 2

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

#ifdef BBC_SLOW_GETSECS
#define NSKIP_READ_BBC 100
#endif

#define range_test(n, l, h) if ((n) < (l) || (n) > (h)) return false
#define bbc_to_decimal(a,b) (bbc_registers[a] * 10 + bbc_registers[b])

static uint8_t bbc_registers[13];
static struct hil_dev *bbcaddr = BBCADDR;

static volatile uint8_t *mcclock =
(volatile uint8_t *)(INTIOBASE + FRODO_BASE + FRODO_CALENDAR);

static bool clock_to_gmt(satime_t *);

static void read_bbc(void);
static uint8_t read_bbc_reg(int);
static uint8_t mc_read(u_int);

satime_t
getsecs(void)
{
static bool clockinited = false;
satime_t timbuf = 0;

if (!clock_to_gmt(&timbuf) && !clockinited)
printf("WARNING: bad date in battery clock\n");
clockinited = true;

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

static bool
clock_to_gmt(satime_t *timbuf)
{
int i;
satime_t tmp;
int year, month, day, hour, min, sec;
#ifdef BBC_SLOW_GETSECS
static satime_t tim_prev = 0;
#endif

if (machineid == HP_425 && mmuid == MMUID_425_E) {
/* 425e uses mcclock on the frodo utility chip */
while ((mc_read(MC_REGA) & MC_REGA_UIP) != 0)
continue;
sec = mc_read(MC_SEC);
min = mc_read(MC_MIN);
hour = mc_read(MC_HOUR);
day = mc_read(MC_DOM);
month = mc_read(MC_MONTH);
year = mc_read(MC_YEAR) + 1900;
} else {
#ifdef BBC_SLOW_GETSECS
/*
* XXX:
* The read_bbc() function against HIL seems extremely slow.
* It was being called on every timeout check via getsecs()
* so it significantly slowed down loading a kernel via NFS.
*
* In most cases (e.g., in common/if_le.c and libsa/net.c),
* timeout checks are performed using getsecs() in busy loops
* without any actual waiting. In such cases, it's not
* necessary to read the precise time from the RTC on
* every call.
*/
static int nskip = NSKIP_READ_BBC;

if (tim_prev != 0 && nskip-- > 0) {
*timbuf = tim_prev;
return true;
}
nskip = NSKIP_READ_BBC;
#endif

/* Use the traditional HIL bbc for all other models */
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 < POSIX_BASE_YEAR)
year += 100;

#ifdef CLOCK_DEBUG
printf("clock todr: %u/%u/%u %u:%u:%u\n",
year, month, day, hour, min, sec);
#endif

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

tmp = 0;

for (i = POSIX_BASE_YEAR; i < year; i++)
tmp += days_per_year(i);
if (is_leap_year(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;

#ifdef BBC_SLOW_GETSECS
tim_prev = tmp;
#endif
*timbuf = tmp;
return true;
}

static void
read_bbc(void)
{
int i;
bool read_okay;

read_okay = false;
while (!read_okay) {
read_okay = true;
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 = false;
}
}

static uint8_t
read_bbc_reg(int reg)
{
uint8_t data = reg;

if (bbcaddr != NULL) {
#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;
}

uint8_t
mc_read(u_int reg)
{
uint8_t datum;

mcclock[0] = (uint8_t)reg;
datum = mcclock[1 << 2]; /* frodo chip has 4 byte stride */

return datum;
}