/*-
 * SPDX-License-Identifier: BSD-2-Clause
 *
 * Copyright (c) 2004-2006 Marcel Moolenaar
 * 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 AUTHOR ``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 AUTHOR 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/bus.h>
#include <sys/conf.h>
#include <machine/bus.h>
#include <sys/lock.h>
#include <sys/mutex.h>
#include <sys/rman.h>
#include <sys/serial.h>

#include <dev/scc/scc_bfe.h>
#include <dev/scc/scc_bus.h>

#include <dev/ic/z8530.h>

#include "scc_if.h"

static int z8530_bfe_attach(struct scc_softc *, int);
static int z8530_bfe_iclear(struct scc_softc *, struct scc_chan *);
static int z8530_bfe_ipend(struct scc_softc *);
static int z8530_bfe_probe(struct scc_softc *);

/* Channel B is always at 0 offset. */
#define CHAN_A  (-(sc->sc_class->cl_range))
#define CHAN_B  0

static kobj_method_t z8530_methods[] = {
        KOBJMETHOD(scc_attach,  z8530_bfe_attach),
        KOBJMETHOD(scc_iclear,  z8530_bfe_iclear),
        KOBJMETHOD(scc_ipend,   z8530_bfe_ipend),
        KOBJMETHOD(scc_probe,   z8530_bfe_probe),
        KOBJMETHOD_END
};

/*
 * escc (macio) spacing.
 */
struct scc_class scc_z8530_escc_class = {
        "z8530 escc class",
        z8530_methods,
        sizeof(struct scc_softc),
        .cl_channels = 2,
        .cl_class = SCC_CLASS_Z8530,
        .cl_modes = SCC_MODE_ASYNC | SCC_MODE_BISYNC | SCC_MODE_HDLC,
        /* Negative .cl_range signifies this is channel spacing. */
        .cl_range = (CHAN_B - 16),
};

/*
 * SUN compatible channel spacing.
 */
struct scc_class scc_z8530_legacy_class = {
        "z8530 legacy class",
        z8530_methods,
        sizeof(struct scc_softc),
        .cl_channels = 2,
        .cl_class = SCC_CLASS_Z8530,
        .cl_modes = SCC_MODE_ASYNC | SCC_MODE_BISYNC | SCC_MODE_HDLC,
        /* Negative .cl_range signifies this is channel spacing. */
        .cl_range = (CHAN_B - 2),
};

/* Multiplexed I/O. */
static __inline uint8_t
scc_getmreg(struct scc_bas *bas, int ch, int reg)
{

        scc_setreg(bas, ch + REG_CTRL, reg);
        scc_barrier(bas);
        return (scc_getreg(bas, ch + REG_CTRL));
}

static int
z8530_bfe_attach(struct scc_softc *sc __unused, int reset __unused)
{

        return (0);
}

static int
z8530_bfe_iclear(struct scc_softc *sc, struct scc_chan *ch)
{
        struct scc_bas *bas;
        int c;

        bas = &sc->sc_bas;
        c = (ch->ch_nr == 1) ? CHAN_A : CHAN_B;
        mtx_lock_spin(&sc->sc_hwmtx);
        if (ch->ch_ipend & SER_INT_TXIDLE) {
                scc_setreg(bas, c + REG_CTRL, CR_RSTTXI);
                scc_barrier(bas);
        }
        if (ch->ch_ipend & SER_INT_RXREADY) {
                scc_getreg(bas, c + REG_DATA);
                scc_barrier(bas);
        }
        if (ch->ch_ipend & (SER_INT_OVERRUN|SER_INT_BREAK))
                scc_setreg(bas, c + REG_CTRL, CR_RSTERR);
        mtx_unlock_spin(&sc->sc_hwmtx);
        return (0);
}

#define SIGCHG(c, i, s, d)                              \
        if (c) {                                        \
                i |= (i & s) ? s : s | d;               \
        } else {                                        \
                i = (i & s) ? (i & ~s) | d : i;         \
        }

static int
z8530_bfe_ipend(struct scc_softc *sc)
{
        struct scc_bas *bas;
        struct scc_chan *ch[2];
        uint32_t sig;
        uint8_t bes, ip, src;

        bas = &sc->sc_bas;
        ch[0] = &sc->sc_chan[0];
        ch[1] = &sc->sc_chan[1];
        ch[0]->ch_ipend = 0;
        ch[1]->ch_ipend = 0;

        mtx_lock_spin(&sc->sc_hwmtx);
        ip = scc_getmreg(bas, CHAN_A, RR_IP);
        if (ip & IP_RIA)
                ch[0]->ch_ipend |= SER_INT_RXREADY;
        if (ip & IP_RIB)
                ch[1]->ch_ipend |= SER_INT_RXREADY;
        if (ip & IP_TIA)
                ch[0]->ch_ipend |= SER_INT_TXIDLE;
        if (ip & IP_TIB)
                ch[1]->ch_ipend |= SER_INT_TXIDLE;
        if (ip & IP_SIA) {
                bes = scc_getmreg(bas, CHAN_A, CR_RSTXSI);
                if (bes & BES_BRK)
                        ch[0]->ch_ipend |= SER_INT_BREAK;
                sig = ch[0]->ch_hwsig;
                SIGCHG(bes & BES_CTS, sig, SER_CTS, SER_DCTS);
                SIGCHG(bes & BES_DCD, sig, SER_DCD, SER_DDCD);
                SIGCHG(bes & BES_SYNC, sig, SER_DSR, SER_DDSR);
                if (sig & SER_MASK_DELTA) {
                        ch[0]->ch_hwsig = sig;
                        ch[0]->ch_ipend |= SER_INT_SIGCHG;
                }
                src = scc_getmreg(bas, CHAN_A, RR_SRC);
                if (src & SRC_OVR)
                        ch[0]->ch_ipend |= SER_INT_OVERRUN;
        }
        if (ip & IP_SIB) {
                bes = scc_getmreg(bas, CHAN_B, CR_RSTXSI);
                if (bes & BES_BRK)
                        ch[1]->ch_ipend |= SER_INT_BREAK;
                sig = ch[1]->ch_hwsig;
                SIGCHG(bes & BES_CTS, sig, SER_CTS, SER_DCTS);
                SIGCHG(bes & BES_DCD, sig, SER_DCD, SER_DDCD);
                SIGCHG(bes & BES_SYNC, sig, SER_DSR, SER_DDSR);
                if (sig & SER_MASK_DELTA) {
                        ch[1]->ch_hwsig = sig;
                        ch[1]->ch_ipend |= SER_INT_SIGCHG;
                }
                src = scc_getmreg(bas, CHAN_B, RR_SRC);
                if (src & SRC_OVR)
                        ch[1]->ch_ipend |= SER_INT_OVERRUN;
        }
        mtx_unlock_spin(&sc->sc_hwmtx);

        return (ch[0]->ch_ipend | ch[1]->ch_ipend);
}

static int
z8530_bfe_probe(struct scc_softc *sc __unused)
{

        return (0);
}