/*      $OpenBSD: getsecs.c,v 1.8 2023/04/13 02:19:04 jsg Exp $ */
/*      $NetBSD: getsecs.c,v 1.4 2022/08/24 14:22:35 nonaka Exp $       */

/*-
 * Copyright (c) 2005 NONAKA Kimihiro
 * All rights reserved.
 *
 * 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 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.
 */

#include <sys/param.h>

#include <libsa.h>

#include <sh/devreg.h>
#include <arch/sh/dev/scireg.h>

#include <arch/landisk/dev/rs5c313reg.h>

/**
 * RICOH RS5C313
 *
 * Web page: http://www.ricoh.co.jp/LSI/product_rtc/3wire/5c313/
 *
 * How to control RS5C313 on LANDISK
 *   see http://www.mizore.jp/wiki/index.php?LANDISK/rtc
 */

uint8_t rtc_read(uint32_t addr);

static void
rtc_init(void)
{

        SHREG_SCSPTR = SCSPTR_SPB1IO | SCSPTR_SPB1DT
                       | SCSPTR_SPB0IO | SCSPTR_SPB0DT;
        delay(1);
}

/* control RTC chip enable */
static void
rtc_ce(int onoff)
{

        if (onoff) {
                _reg_write_1(0xb0000003, (1 << 1));
        } else {
                _reg_write_1(0xb0000003, (0 << 1));
        }
        delay(1);
}

static inline void
rtc_clk(int onoff)
{

        if (onoff) {
                SHREG_SCSPTR |= SCSPTR_SPB0DT;
        } else {
                SHREG_SCSPTR &= ~SCSPTR_SPB0DT;
        }
        delay(1);
}

static void
rtc_dir(int output)
{

        if (output) {
                SHREG_SCSPTR |= SCSPTR_SPB1IO;
        } else {
                SHREG_SCSPTR &= ~SCSPTR_SPB1IO;
        }
        delay(1);
}

/* data-out */
static void
rtc_do(int onoff)
{

        if (onoff) {
                SHREG_SCSPTR |= SCSPTR_SPB1DT;
        } else {
                SHREG_SCSPTR &= ~SCSPTR_SPB1DT;
        }
        delay(1);

        rtc_clk(0);
        rtc_clk(1);
}

/* data-in */
static int
rtc_di(void)
{
        int d;

        d = (SHREG_SCSPTR & SCSPTR_SPB1DT) ? 1 : 0;

        rtc_clk(0);
        rtc_clk(1);

        return d;
}

uint8_t
rtc_read(uint32_t addr)
{
        uint8_t data;

        rtc_init();
        rtc_ce(1);

        rtc_dir(1);
        rtc_do(1);              /* Don't care */
        rtc_do(1);              /* R/#W = 1(READ) */
        rtc_do(1);              /* AD = 1 */
        rtc_do(0);              /* DT = 0 */
        rtc_do(addr & 0x8);     /* A3 */
        rtc_do(addr & 0x4);     /* A2 */
        rtc_do(addr & 0x2);     /* A1 */
        rtc_do(addr & 0x1);     /* A0 */

        rtc_dir(0);
        (void)rtc_di();
        (void)rtc_di();
        (void)rtc_di();
        (void)rtc_di();
        data = rtc_di();        /* D3 */
        data <<= 1;
        data |= rtc_di();       /* D2 */
        data <<= 1;
        data |= rtc_di();       /* D1 */
        data <<= 1;
        data |= rtc_di();       /* D0 */

        rtc_ce(0);

        return data & 0xf;
}

time_t
getsecs(void)
{
        uint32_t sec, min, hour, day;
#if 0
        uint32_t mon, year;
#endif
        time_t secs;

        sec = rtc_read(RS5C313_SEC1);
        sec += rtc_read(RS5C313_SEC10) * 10;
        min = rtc_read(RS5C313_MIN1);
        min += rtc_read(RS5C313_MIN10) * 10;
        hour = rtc_read(RS5C313_HOUR1);
        hour += rtc_read(RS5C313_HOUR10) * 10;
        day = rtc_read(RS5C313_DAY1);
        day += rtc_read(RS5C313_DAY10) * 10;
#if 0
        mon = rtc_read(RS5C313_MON1);
        mon += rtc_read(RS5C313_MON10) * 10;
        year = rtc_read(RS5C313_YEAR1);
        year += rtc_read(RS5C313_YEAR10) * 10;
#endif

        secs = sec;
        secs += min * 60;
        secs += hour * 60 * 60;
        secs += day * 60 * 60 * 24;
#if 0
        /* XXX mon, year */
#endif

#if defined(DEBUG)
        printf("getsecs: secs = %d\n", (uint32_t)secs);
#endif

        return secs;
}