/* $OpenBSD: timekeeper.c,v 1.11 2022/04/06 18:59:26 naddy Exp $ */
/* $NetBSD: timekeeper.c,v 1.1 2000/01/05 08:48:56 nisimura Exp $ */

/*-
 * Copyright (c) 2000 The NetBSD Foundation, Inc.
 * All rights reserved.
 *
 * This code is derived from software contributed to The NetBSD Foundation
 * by Tohru Nishimura.
 *
 * 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 NETBSD FOUNDATION, INC. 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 FOUNDATION 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.
 */

#include <sys/param.h>
#include <sys/systm.h>
#include <sys/device.h>
#include <sys/kernel.h>
#include <sys/evcount.h>

#include <machine/autoconf.h>
#include <machine/board.h>      /* machtype value */
#include <machine/cpu.h>

#include <dev/clock_subr.h>

#include <luna88k/luna88k/clockvar.h>
#include <luna88k/dev/timekeeper.h>

#define MK_YEAR0        1970    /* year offset of MK */
#define DS_YEAR0        1990    /* year offset of DS */

struct timekeeper_softc {
        struct device sc_dev;
        void *sc_clock, *sc_nvram;
        int sc_nvramsize;
        struct evcount sc_count;
};

/*
 * BCD to decimal and decimal to BCD.
 */
#define FROMBCD(x)      (((x) >> 4) * 10 + ((x) & 0xf))
#define TOBCD(x)        (((x) / 10 * 16) + ((x) % 10))

int  clock_match(struct device *, void *, void *);
void clock_attach(struct device *, struct device *, void *);

const struct cfattach clock_ca = {
        sizeof (struct timekeeper_softc), clock_match, clock_attach
};

struct cfdriver clock_cd = {
        NULL, "clock", DV_DULL
};

void mkclock_get(struct device *, time_t, struct clock_ymdhms *);
void mkclock_set(struct device *, struct clock_ymdhms *);
void dsclock_get(struct device *, time_t, struct clock_ymdhms *);
void dsclock_set(struct device *, struct clock_ymdhms *);

const struct clockfns mkclock_clockfns = {
        NULL /* never used */, mkclock_get, mkclock_set,
};

const struct clockfns dsclock_clockfns = {
        NULL /* never used */, dsclock_get, dsclock_set,
};

int
clock_match(struct device *parent, void *match, void *aux)
{
        struct mainbus_attach_args *ma = aux;

        if (strcmp(ma->ma_name, clock_cd.cd_name))
                return 0;
        return 1;
}

extern int machtype; /* in machdep.c */

void
clock_attach(struct device *parent, struct device *self, void *aux)
{
        struct timekeeper_softc *sc = (void *)self;
        struct mainbus_attach_args *ma = aux;
        const struct clockfns *clockwork;

        switch (machtype) {
        default:
        case LUNA_88K:  /* Mostek MK48T02 */
                sc->sc_clock = (void *)(ma->ma_addr + MK_NVRAM_SPACE);
                sc->sc_nvram = (void *)ma->ma_addr;
                sc->sc_nvramsize = MK_NVRAM_SPACE;
                clockwork = &mkclock_clockfns;
                printf(": MK48T02\n");
                break;
        case LUNA_88K2: /* Dallas DS1397 */
                sc->sc_clock = (void *)ma->ma_addr;
                sc->sc_nvram = (void *)(ma->ma_addr + 50);
                sc->sc_nvramsize = 50;
                clockwork = &dsclock_clockfns;
                printf(": DS1397\n");
                break;
        }

        evcount_attach(&sc->sc_count, self->dv_xname, &ma->ma_ilvl);

        clockattach(&sc->sc_dev, clockwork, &sc->sc_count);
}

/*
 * On LUNA-88K, NVRAM contents and Timekeeper registers are mapped on the
 * most significant byte of each 32bit word. (i.e. 4-bytes stride)
 *
 * Get the time of day, based on the clock's value and/or the base value.
 */
void
mkclock_get(struct device *dev, time_t base, struct clock_ymdhms *dt)
{
        struct timekeeper_softc *sc = (void *)dev;
        volatile u_int32_t *chiptime = (void *)sc->sc_clock;
        int s;

        s = splclock();

        /* enable read (stop time) */
        chiptime[MK_CSR] |= (MK_CSR_READ << 24);

        dt->dt_sec  = FROMBCD(chiptime[MK_SEC]   >> 24);
        dt->dt_min  = FROMBCD(chiptime[MK_MIN]   >> 24);
        dt->dt_hour = FROMBCD(chiptime[MK_HOUR]  >> 24);
        dt->dt_wday = FROMBCD(chiptime[MK_DOW]   >> 24);
        dt->dt_day  = FROMBCD(chiptime[MK_DOM]   >> 24);
        dt->dt_mon  = FROMBCD(chiptime[MK_MONTH] >> 24);
        dt->dt_year = FROMBCD(chiptime[MK_YEAR]  >> 24);

        chiptime[MK_CSR] &= (~MK_CSR_READ << 24);       /* time wears on */

        /* UniOS-Mach doesn't set the correct BCD year after Y2K */
        if (dt->dt_year > 100) dt->dt_year -= (MK_YEAR0 % 100);

        dt->dt_year += MK_YEAR0;
        splx(s);
#ifdef TIMEKEEPER_DEBUG
        printf("get %02d/%02d/%02d %02d:%02d:%02d\n",
            dt->dt_year, dt->dt_mon, dt->dt_day,
            dt->dt_hour, dt->dt_min, dt->dt_sec);
#endif
}

/*
 * Reset the TODR based on the time value.
 */
void
mkclock_set(struct device *dev, struct clock_ymdhms *dt)
{
        struct timekeeper_softc *sc = (void *)dev;
        volatile u_int32_t *chiptime = (void *)sc->sc_clock;
        volatile u_int32_t *stamp = (void *)(sc->sc_nvram + (4 * 0x10));
        int s;

        s = splclock();
        chiptime[MK_CSR]  |= (MK_CSR_WRITE << 24);      /* enable write */

        chiptime[MK_SEC]   = TOBCD(dt->dt_sec)  << 24;
        chiptime[MK_MIN]   = TOBCD(dt->dt_min)  << 24;
        chiptime[MK_HOUR]  = TOBCD(dt->dt_hour) << 24;
        chiptime[MK_DOW]   = TOBCD(dt->dt_wday) << 24;
        chiptime[MK_DOM]   = TOBCD(dt->dt_day)  << 24;
        chiptime[MK_MONTH] = TOBCD(dt->dt_mon)  << 24;
        /* XXX: We don't consider UniOS-Mach Y2K problem */
        chiptime[MK_YEAR]  = TOBCD(dt->dt_year - MK_YEAR0) << 24;

        chiptime[MK_CSR]  &= (~MK_CSR_WRITE << 24);     /* load them up */
        splx(s);
#ifdef TIMEKEEPER_DEBUG
        printf("set %02d/%02d/%02d %02d:%02d:%02d\n",
            dt->dt_year, dt->dt_mon, dt->dt_day,
            dt->dt_hour, dt->dt_min, dt->dt_sec);
#endif

        /* Write a stamp at NVRAM address 0x10-0x13 */
        stamp[0] = 'R' << 24; stamp[1] = 'T' << 24;
        stamp[2] = 'C' << 24; stamp[3] = '\0' << 24;
}

#define _DS_GET(off, data) \
        do { *chiptime = (off); (data) = (*chipdata); } while (0)
#define _DS_SET(off, data) \
        do { *chiptime = (off); *chipdata = (u_int8_t)(data); } while (0)
#define _DS_GET_BCD(off, data) \
        do { \
                u_int8_t c; \
                *chiptime = (off); \
                c = *chipdata; (data) = FROMBCD(c); \
        } while (0)
#define _DS_SET_BCD(off, data) \
        do { \
                *chiptime = (off); \
                *chipdata = TOBCD((u_int8_t)(data)); \
        } while (0)

/*
 * Get the time of day, based on the clock's value and/or the base value.
 */
void
dsclock_get(struct device *dev, time_t base, struct clock_ymdhms *dt)
{
        struct timekeeper_softc *sc = (void *)dev;
        volatile u_int8_t *chiptime = (void *)sc->sc_clock;
        volatile u_int8_t *chipdata = (void *)(sc->sc_clock + 1);
        int s;
        u_int8_t c;

        s = splclock();

        /* specify 24hr and BCD mode */
        _DS_GET(DS_REGB, c);
        c |= DS_REGB_24HR;
        c &= ~DS_REGB_BINARY;
        _DS_SET(DS_REGB, c);

        /* update in progress; spin loop */
        for (;;) {
                *chiptime = DS_REGA;
                if ((*chipdata & DS_REGA_UIP) == 0)
                        break;
        }

        _DS_GET_BCD(DS_SEC,   dt->dt_sec);
        _DS_GET_BCD(DS_MIN,   dt->dt_min);
        _DS_GET_BCD(DS_HOUR,  dt->dt_hour);
        _DS_GET_BCD(DS_DOW,   dt->dt_wday);
        _DS_GET_BCD(DS_DOM,   dt->dt_day);
        _DS_GET_BCD(DS_MONTH, dt->dt_mon);
        _DS_GET_BCD(DS_YEAR,  dt->dt_year);

        /* UniOS-Mach doesn't set the correct BCD year after Y2K */
        if (dt->dt_year > 100) dt->dt_year -= (DS_YEAR0 % 100);

        dt->dt_year += DS_YEAR0;
        splx(s);

#ifdef TIMEKEEPER_DEBUG
        printf("get %02d/%02d/%02d %02d:%02d:%02d\n",
            dt->dt_year, dt->dt_mon, dt->dt_day,
            dt->dt_hour, dt->dt_min, dt->dt_sec);
#endif
}

/*
 * Reset the TODR based on the time value.
 */
void
dsclock_set(struct device *dev, struct clock_ymdhms *dt)
{
        struct timekeeper_softc *sc = (void *)dev;
        volatile u_int8_t *chiptime = (void *)sc->sc_clock;
        volatile u_int8_t *chipdata = (void *)(sc->sc_clock + 1);
        int s;
        u_int8_t c;

        s = splclock();
        
        /* enable write */
        _DS_GET(DS_REGB, c);
        c |= DS_REGB_SET;
        _DS_SET(DS_REGB, c);

        _DS_SET_BCD(DS_SEC,   dt->dt_sec);
        _DS_SET_BCD(DS_MIN,   dt->dt_min);
        _DS_SET_BCD(DS_HOUR,  dt->dt_hour);
        _DS_SET_BCD(DS_DOW,   dt->dt_wday);
        _DS_SET_BCD(DS_DOM,   dt->dt_day);
        _DS_SET_BCD(DS_MONTH, dt->dt_mon);
        /* XXX: We don't consider UniOS-Mach Y2K problem */
        _DS_SET_BCD(DS_YEAR,  dt->dt_year - DS_YEAR0);

        _DS_GET(DS_REGB, c);
        c &= ~DS_REGB_SET;
        _DS_SET(DS_REGB, c);

        splx(s);

#ifdef TIMEKEEPER_DEBUG
        printf("set %02d/%02d/%02d %02d:%02d:%02d\n",
            dt->dt_year, dt->dt_mon, dt->dt_day,
            dt->dt_hour, dt->dt_min, dt->dt_sec);
#endif
}