/*      $OpenBSD: mk48txx.c,v 1.10 2022/10/16 01:22:39 jsg Exp $        */
/*      $NetBSD: mk48txx.c,v 1.7 2001/04/08 17:05:10 tsutsui Exp $ */
/*-
 * Copyright (c) 2000 The NetBSD Foundation, Inc.
 * All rights reserved.
 *
 * This code is derived from software contributed to The NetBSD Foundation
 * by Paul Kranenburg.
 *
 * 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.
 */

/*
 * Mostek MK48T02, MK48T08, MK48T59 time-of-day chip subroutines.
 */

#include <sys/param.h>
#include <sys/malloc.h>
#include <sys/systm.h>
#include <sys/errno.h>

#include <machine/bus.h>
#include <dev/clock_subr.h>
#include <dev/ic/mk48txxreg.h>


struct mk48txx {
        bus_space_tag_t mk_bt;          /* bus tag & handle */
        bus_space_handle_t mk_bh;       /* */
        bus_size_t      mk_nvramsz;     /* Size of NVRAM on the chip */
        bus_size_t      mk_clkoffset;   /* Offset in NVRAM to clock bits */
        u_int           mk_year0;       /* What year is represented on the system
                                           by the chip's year counter at 0 */
};

int mk48txx_gettime(todr_chip_handle_t, struct timeval *);
int mk48txx_settime(todr_chip_handle_t, struct timeval *);

int mk48txx_auto_century_adjust = 1;

struct {
        const char *name;
        bus_size_t nvramsz;
        bus_size_t clkoff;
        int flags;
#define MK48TXX_EXT_REGISTERS   1       /* Has extended register set */
} mk48txx_models[] = {
        { "mk48t02", MK48T02_CLKSZ, MK48T02_CLKOFF, 0 },
        { "mk48t08", MK48T08_CLKSZ, MK48T08_CLKOFF, 0 },
        { "mk48t18", MK48T18_CLKSZ, MK48T18_CLKOFF, 0 },
        { "mk48t59", MK48T59_CLKSZ, MK48T59_CLKOFF, MK48TXX_EXT_REGISTERS },
};

todr_chip_handle_t
mk48txx_attach(bus_space_tag_t bt, bus_space_handle_t bh, const char *model,
    int year0)
{
        todr_chip_handle_t handle;
        struct mk48txx *mk;
        bus_size_t nvramsz, clkoff;
        int sz;
        int i;

        printf(": %s", model);

        i = nitems(mk48txx_models);
        while (--i >= 0) {
                if (strcmp(model, mk48txx_models[i].name) == 0) {
                        nvramsz = mk48txx_models[i].nvramsz;
                        clkoff = mk48txx_models[i].clkoff;
                        break;
                }
        }
        if (i < 0) {
                printf(": unsupported model");
                return (NULL);
        }

        sz = ALIGN(sizeof(struct todr_chip_handle)) + sizeof(struct mk48txx);
        handle = malloc(sz, M_DEVBUF, M_NOWAIT);
        if (handle == NULL) {
                printf(": failed to allocate memory");
                return NULL;
        }
        mk = (struct mk48txx *)((u_long)handle +
                                 ALIGN(sizeof(struct todr_chip_handle)));
        handle->cookie = mk;
        handle->todr_gettime = mk48txx_gettime;
        handle->todr_settime = mk48txx_settime;
        handle->todr_setwen = NULL;
        handle->todr_quality = 0;
        mk->mk_bt = bt;
        mk->mk_bh = bh;
        mk->mk_nvramsz = nvramsz;
        mk->mk_clkoffset = clkoff;
        mk->mk_year0 = year0;

        return (handle);
}

/*
 * Get time-of-day and convert to a `struct timeval'
 * Return 0 on success; an error number otherwise.
 */
int
mk48txx_gettime(todr_chip_handle_t handle, struct timeval *tv)
{
        struct mk48txx *mk = handle->cookie;
        bus_space_tag_t bt = mk->mk_bt;
        bus_space_handle_t bh = mk->mk_bh;
        bus_size_t clkoff = mk->mk_clkoffset;
        struct clock_ymdhms dt;
        int year;
        u_int8_t csr;

        todr_wenable(handle, 1);

        /* enable read (stop time) */
        csr = bus_space_read_1(bt, bh, clkoff + MK48TXX_ICSR);
        csr |= MK48TXX_CSR_READ;
        bus_space_write_1(bt, bh, clkoff + MK48TXX_ICSR, csr);

        dt.dt_sec = FROMBCD(bus_space_read_1(bt, bh, clkoff + MK48TXX_ISEC));
        dt.dt_min = FROMBCD(bus_space_read_1(bt, bh, clkoff + MK48TXX_IMIN));
        dt.dt_hour = FROMBCD(bus_space_read_1(bt, bh, clkoff + MK48TXX_IHOUR));
        dt.dt_day = FROMBCD(bus_space_read_1(bt, bh, clkoff + MK48TXX_IDAY));
        dt.dt_wday = FROMBCD(bus_space_read_1(bt, bh, clkoff + MK48TXX_IWDAY));
        dt.dt_mon = FROMBCD(bus_space_read_1(bt, bh, clkoff + MK48TXX_IMON));
        year = FROMBCD(bus_space_read_1(bt, bh, clkoff + MK48TXX_IYEAR));

        year += mk->mk_year0;
        if (year < POSIX_BASE_YEAR && mk48txx_auto_century_adjust != 0 &&
            mk->mk_year0 >= POSIX_BASE_YEAR)
                year += 100;

        dt.dt_year = year;

        /* time wears on */
        csr = bus_space_read_1(bt, bh, clkoff + MK48TXX_ICSR);
        csr &= ~MK48TXX_CSR_READ;
        bus_space_write_1(bt, bh, clkoff + MK48TXX_ICSR, csr);
        todr_wenable(handle, 0);

        /* simple sanity checks */
        if (dt.dt_mon > 12 || dt.dt_day > 31 ||
            dt.dt_hour >= 24 || dt.dt_min >= 60 || dt.dt_sec >= 60)
                return (1);

        tv->tv_sec = clock_ymdhms_to_secs(&dt);
        tv->tv_usec = 0;
        return (0);
}

/*
 * Set the time-of-day clock based on the value of the `struct timeval' arg.
 * Return 0 on success; an error number otherwise.
 */
int
mk48txx_settime(todr_chip_handle_t handle, struct timeval *tv)
{
        struct mk48txx *mk = handle->cookie;
        bus_space_tag_t bt = mk->mk_bt;
        bus_space_handle_t bh = mk->mk_bh;
        bus_size_t clkoff = mk->mk_clkoffset;
        struct clock_ymdhms dt;
        u_int8_t csr;
        int year;

        /* Note: we ignore `tv_usec' */
        clock_secs_to_ymdhms(tv->tv_sec, &dt);

        year = dt.dt_year - mk->mk_year0;
        if (year > 99 && mk48txx_auto_century_adjust != 0)
                year -= 100;

        todr_wenable(handle, 1);
        /* enable write */
        csr = bus_space_read_1(bt, bh, clkoff + MK48TXX_ICSR);
        csr |= MK48TXX_CSR_WRITE;
        bus_space_write_1(bt, bh, clkoff + MK48TXX_ICSR, csr);

        bus_space_write_1(bt, bh, clkoff + MK48TXX_ISEC, TOBCD(dt.dt_sec));
        bus_space_write_1(bt, bh, clkoff + MK48TXX_IMIN, TOBCD(dt.dt_min));
        bus_space_write_1(bt, bh, clkoff + MK48TXX_IHOUR, TOBCD(dt.dt_hour));
        bus_space_write_1(bt, bh, clkoff + MK48TXX_IWDAY, TOBCD(dt.dt_wday));
        bus_space_write_1(bt, bh, clkoff + MK48TXX_IDAY, TOBCD(dt.dt_day));
        bus_space_write_1(bt, bh, clkoff + MK48TXX_IMON, TOBCD(dt.dt_mon));
        bus_space_write_1(bt, bh, clkoff + MK48TXX_IYEAR, TOBCD(year));

        /* load them up */
        csr = bus_space_read_1(bt, bh, clkoff + MK48TXX_ICSR);
        csr &= ~MK48TXX_CSR_WRITE;
        bus_space_write_1(bt, bh, clkoff + MK48TXX_ICSR, csr);
        todr_wenable(handle, 0);
        return (0);
}

int
mk48txx_get_nvram_size(todr_chip_handle_t handle, bus_size_t *vp)
{
        struct mk48txx *mk = handle->cookie;
        *vp = mk->mk_nvramsz;
        return (0);
}