/* $OpenBSD: siotty.c,v 1.25 2021/01/09 02:34:21 aoyama Exp $ */
/* $NetBSD: siotty.c,v 1.9 2002/03/17 19:40:43 atatat 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/conf.h>
#include <sys/ioctl.h>
#include <sys/malloc.h>
#include <sys/proc.h>
#include <sys/tty.h>
#include <sys/uio.h>
#include <sys/fcntl.h>
#include <dev/cons.h>

#include <machine/board.h>
#include <machine/cpu.h>

#include <luna88k/dev/sioreg.h>
#include <luna88k/dev/siovar.h>

#define TIOCM_BREAK 01000 /* non standard use */

static const u_int8_t ch0_regs[6] = {
        WR0_RSTINT,                             /* reset E/S interrupt */
        WR1_RXALLS | WR1_TXENBL,                /* Rx per char, Tx */
        0,                                      /* */
        WR3_RX8BIT | WR3_RXENBL,                /* Rx */
        WR4_BAUD96 | WR4_STOP1,                 /* Tx/Rx */
        WR5_TX8BIT | WR5_TXENBL | WR5_DTR | WR5_RTS, /* Tx */
};

static const struct speedtab siospeedtab[] = {
        { 2400, WR4_BAUD24, },
        { 4800, WR4_BAUD48, },
        { 9600, WR4_BAUD96, },
        { -1,   0, },
};

struct siotty_softc {
        struct device   sc_dev;
        struct tty      *sc_tty;
        struct sioreg   *sc_ctl;
        u_int           sc_flags;
        u_int8_t        sc_wr[6];
        void            *sc_si;         /* software interrupt handler */
        u_int           sc_hwflags;
#define SIOTTY_HW_CONSOLE       0x0001

        u_int8_t        *sc_rbuf;
        u_int8_t        *sc_rbufend;
        u_int8_t * volatile sc_rbget;
        u_int8_t * volatile sc_rbput;
        volatile u_int  sc_rbavail;

        u_int8_t        *sc_tba;
        u_int           sc_tbc;

        bool            sc_rx_ready;
        bool            sc_tx_busy;
        bool            sc_tx_done;
};

#define SIOTTY_RING_SIZE        2048
u_int siotty_rbuf_size = SIOTTY_RING_SIZE;

cdev_decl(sio);
void siostart(struct tty *);
int  sioparam(struct tty *, struct termios *);
void siottyintr(void *);
void siottysoft(void *);
void siotty_rxsoft(struct siotty_softc *, struct tty *);
void siotty_txsoft(struct siotty_softc *, struct tty *);
int  siomctl(struct siotty_softc *, int, int);

int  siotty_match(struct device *, void *, void *);
void siotty_attach(struct device *, struct device *, void *);

const struct cfattach siotty_ca = {
        sizeof(struct siotty_softc), siotty_match, siotty_attach
};

struct cfdriver siotty_cd = {
        NULL, "siotty", DV_TTY
};

int 
siotty_match(struct device *parent, void *cf, void *aux)
{
        struct sio_attach_args *args = aux;

        if (args->channel != 0) /* XXX allow tty on Ch.B XXX */
                return 0;
        return 1;
}

void 
siotty_attach(struct device *parent, struct device *self, void *aux)
{
        struct sio_softc *siosc = (void *)parent;
        struct siotty_softc *sc = (void *)self;
        struct sio_attach_args *args = aux;
        int channel;
        struct tty *tp;

        channel = args->channel;
        sc->sc_ctl = &siosc->sc_ctl[channel];
        memcpy(sc->sc_wr, ch0_regs, sizeof(ch0_regs));
        siosc->sc_intrhand[channel].ih_func = siottyintr;
        siosc->sc_intrhand[channel].ih_arg = sc;
        if (args->hwflags == 1)
                sc->sc_hwflags |= SIOTTY_HW_CONSOLE;

        if (sc->sc_hwflags & SIOTTY_HW_CONSOLE) {
                printf(" (console)");
                sc->sc_flags = TIOCFLAG_SOFTCAR;
        } else {
                setsioreg(sc->sc_ctl, WR0, WR0_CHANRST);
                setsioreg(sc->sc_ctl, WR2A, WR2_VEC86 | WR2_INTR_1);
                setsioreg(sc->sc_ctl, WR2B, 0);
                setsioreg(sc->sc_ctl, WR0, sc->sc_wr[WR0]);
                setsioreg(sc->sc_ctl, WR4, sc->sc_wr[WR4]);
                setsioreg(sc->sc_ctl, WR3, sc->sc_wr[WR3]);
                setsioreg(sc->sc_ctl, WR5, sc->sc_wr[WR5]);
                setsioreg(sc->sc_ctl, WR0, sc->sc_wr[WR0]);
        }
        setsioreg(sc->sc_ctl, WR1, sc->sc_wr[WR1]); /* now interrupt driven */

        printf("\n");

        sc->sc_rbuf = malloc(siotty_rbuf_size * 2, M_DEVBUF, M_NOWAIT);
        if (sc->sc_rbuf == NULL) {
                printf("%s: unable to allocate ring buffer\n",
                    (sc->sc_dev).dv_xname);
                return;
        }
        sc->sc_rbufend = sc->sc_rbuf + (siotty_rbuf_size * 2);
        sc->sc_rbput = sc->sc_rbget = sc->sc_rbuf;
        sc->sc_rbavail = siotty_rbuf_size;

        tp = ttymalloc(0);
        tp->t_oproc = siostart;
        tp->t_param = sioparam;
        tp->t_hwiflow = NULL /* XXX siohwiflow XXX */;
        if (sc->sc_hwflags & SIOTTY_HW_CONSOLE)
                tp->t_dev = cn_tab->cn_dev;
        sc->sc_tty = tp;

        sc->sc_si = softintr_establish(IPL_SOFTTTY, siottysoft, sc);
}

/*--------------------  low level routine --------------------*/

void
siottyintr(void *arg)
{
        struct siotty_softc *sc;
        struct sioreg *sio;
        u_int8_t *put, *end;
        u_int8_t c;
        u_int16_t rr;
        int cc;

        sc = arg;
        end = sc->sc_rbufend;
        put = sc->sc_rbput;
        cc = sc->sc_rbavail;

        sio = sc->sc_ctl;
        rr = getsiocsr(sio);
        if (rr & RR_RXRDY) {
                do {
                        if (cc > 0) {
                                c = sio->sio_data;
                                put[0] = c;
                                put[1] = rr & 0xff;
                                put += 2;
                                if (put >= end)
                                        put = sc->sc_rbuf;
                                cc--;
                        }
                        if (rr & (RR_FRAMING | RR_OVERRUN | RR_PARITY))
                                sio->sio_cmd = WR0_ERRRST;

                        sc->sc_rbput = put;
                        sc->sc_rbavail = cc;
                        sc->sc_rx_ready = true;
                } while ((rr = getsiocsr(sio)) & RR_RXRDY);
        }
        if (rr & RR_TXRDY) {
                sio->sio_cmd = WR0_RSTPEND;
                if (sc->sc_tbc > 0) {
                        sio->sio_data = *sc->sc_tba;
                        sc->sc_tba++;
                        sc->sc_tbc--;
                } else {
                        if (sc->sc_tx_busy) {
                                sc->sc_tx_busy = false;
                                sc->sc_tx_done = true;
                        }
                }
        }
        softintr_schedule(sc->sc_si);
}

void
siottysoft(void *arg)
{
        struct siotty_softc *sc;
        struct tty *tp;

        sc = arg;
        tp = sc->sc_tty;

        if (sc->sc_rx_ready) {
                sc->sc_rx_ready = false;
                siotty_rxsoft(sc, tp);
        }
        if (sc->sc_tx_done) {
                sc->sc_tx_done = false;
                siotty_txsoft(sc, tp);
        }
}

void
siotty_rxsoft(struct siotty_softc *sc, struct tty *tp)
{
        uint8_t *get, *end;
        u_int cc, scc;
        unsigned int code;
        uint8_t stat;
        int s;

        end = sc->sc_rbufend;
        get = sc->sc_rbget;
        scc = cc = siotty_rbuf_size - sc->sc_rbavail;

        if (cc == siotty_rbuf_size) {
                printf("%s: rx buffer overflow\n", (sc->sc_dev).dv_xname);
        }

        while (cc > 0) {
                code = get[0];
                stat = get[1];
                if ((stat & RR_FRAMING) != 0)
                        code |= TTY_FE;
                else if ((stat & RR_PARITY) != 0)
                        code |= TTY_PE;

                (*linesw[tp->t_line].l_rint)(code, tp);
                get += 2;
                if (get >= end)
                        get = sc->sc_rbuf;
                cc--;
        }

        if (cc != scc) {
                s = spltty();
                sc->sc_rbget = get;
                sc->sc_rbavail += scc - cc;
                splx(s);
        }
}

void
siotty_txsoft(struct siotty_softc *sc, struct tty *tp)
{

        tp->t_state &= ~TS_BUSY;
        if ((tp->t_state & TS_FLUSH) != 0)
                tp->t_state &= ~TS_FLUSH;
        else
                ndflush(&tp->t_outq, (int)(sc->sc_tba - tp->t_outq.c_cf));
        (*linesw[tp->t_line].l_start)(tp);
}

void
siostart(struct tty *tp)
{
        struct siotty_softc *sc = siotty_cd.cd_devs[minor(tp->t_dev)];
        int s;
        u_int8_t *tba;
        int tbc;
 
        s = spltty();
        if (tp->t_state & (TS_BUSY|TS_TIMEOUT|TS_TTSTOP))
                goto out;
        ttwakeupwr(tp);
        if (tp->t_outq.c_cc == 0)
                goto out;

        tp->t_state |= TS_BUSY;

        tba = tp->t_outq.c_cf;
        tbc = ndqb(&tp->t_outq, 0);

        sc->sc_tba = tba;
        sc->sc_tbc = tbc;
        sc->sc_tx_busy = true;

        sc->sc_ctl->sio_data = *sc->sc_tba;
        sc->sc_tba++;
        sc->sc_tbc--;
out:
        splx(s);
}

int
siostop(struct tty *tp, int flag)
{
        int s;

        s = spltty();
        if (TS_BUSY == (tp->t_state & (TS_BUSY|TS_TTSTOP))) {
                /*
                 * Device is transmitting; must stop it.
                 */
                tp->t_state |= TS_FLUSH;
        }
        splx(s);
        return (0);
}

int
sioparam(struct tty *tp, struct termios *t)
{
        struct siotty_softc *sc = siotty_cd.cd_devs[minor(tp->t_dev)];
        int wr4, s;

        if (t->c_ispeed && t->c_ispeed != t->c_ospeed)
                return EINVAL;
        wr4 = ttspeedtab(t->c_ospeed, siospeedtab);
        if (wr4 < 0)
                return EINVAL;

        if (sc->sc_flags & TIOCFLAG_SOFTCAR) {
                t->c_cflag |= CLOCAL;
                t->c_cflag &= ~HUPCL;
        }
        if (sc->sc_flags & TIOCFLAG_CLOCAL)
                t->c_cflag |= CLOCAL;

        /*
         * If there were no changes, don't do anything.  This avoids dropping
         * input and improves performance when all we did was frob things like
         * VMIN and VTIME.
         */
        if (tp->t_ospeed == t->c_ospeed && tp->t_cflag == t->c_cflag)
                return 0;

        tp->t_ispeed = t->c_ispeed;
        tp->t_ospeed = t->c_ospeed;
        tp->t_cflag = t->c_cflag;

        sc->sc_wr[WR3] &= 0x3f;
        sc->sc_wr[WR5] &= 0x9f;
        switch (tp->t_cflag & CSIZE) {
        case CS7:
                sc->sc_wr[WR3] |= WR3_RX7BIT; sc->sc_wr[WR5] |= WR5_TX7BIT;
                break;
        case CS8:
                sc->sc_wr[WR3] |= WR3_RX8BIT; sc->sc_wr[WR5] |= WR5_TX8BIT;
                break;
        }
        if (tp->t_cflag & PARENB) {
                wr4 |= WR4_PARENAB;
                if ((tp->t_cflag & PARODD) == 0)
                        wr4 |= WR4_EPARITY;
        }
        wr4 |= (tp->t_cflag & CSTOPB) ? WR4_STOP2 : WR4_STOP1;  
        sc->sc_wr[WR4] = wr4;

        s = spltty();
        setsioreg(sc->sc_ctl, WR4, sc->sc_wr[WR4]);
        setsioreg(sc->sc_ctl, WR3, sc->sc_wr[WR3]);
        setsioreg(sc->sc_ctl, WR5, sc->sc_wr[WR5]);
        splx(s);

        return 0;
}

int
siomctl(struct siotty_softc *sc, int control, int op)
{
        int val, s, wr5, rr;

        val = 0;
        if (control & TIOCM_BREAK)
                val |= WR5_BREAK;
        if (control & TIOCM_DTR)
                val |= WR5_DTR;
        if (control & TIOCM_RTS)
                val |= WR5_RTS;
        s = spltty();
        wr5 = sc->sc_wr[WR5];
        switch (op) {
        case DMSET:
                wr5 &= ~(WR5_BREAK|WR5_DTR|WR5_RTS);
                /* FALLTHROUGH */
        case DMBIS:
                wr5 |= val;
                break;
        case DMBIC:
                wr5 &= ~val;
                break;
        case DMGET:
                val = 0;
                rr = getsiocsr(sc->sc_ctl);
                if (wr5 & WR5_DTR)
                        val |= TIOCM_DTR;
                if (wr5 & WR5_RTS)
                        val |= TIOCM_RTS;
                if (rr & RR_CTS)
                        val |= TIOCM_CTS;
                if (rr & RR_DCD)
                        val |= TIOCM_CD;
                goto done;
        }
        sc->sc_wr[WR5] = wr5;
        setsioreg(sc->sc_ctl, WR5, wr5);
        val = 0;
done:
        splx(s);
        return val;
}

/*--------------------  cdevsw[] interface --------------------*/

int
sioopen(dev_t dev, int flag, int mode, struct proc *p)
{
        struct siotty_softc *sc;
        struct tty *tp;
        int s;

        if ((sc = siotty_cd.cd_devs[minor(dev)]) == NULL)
                return ENXIO;

        tp = sc->sc_tty;

        if ((tp->t_state & TS_ISOPEN) && (tp->t_state & TS_XCLUDE)
            && suser(p) != 0)
                return EBUSY;

        if ((tp->t_state & TS_ISOPEN) == 0) {
                struct termios t;

                tp->t_dev = dev;
                t.c_ispeed = t.c_ospeed = TTYDEF_SPEED;
                t.c_cflag = TTYDEF_CFLAG;
                tp->t_ospeed = 0; /* force register update */
                (void)sioparam(tp, &t);
                tp->t_iflag = TTYDEF_IFLAG;
                tp->t_oflag = TTYDEF_OFLAG;
                tp->t_lflag = TTYDEF_LFLAG;
                ttychars(tp);
                ttsetwater(tp);
                /* raise RTS and DTR here; but, DTR lead is not wired */
                /* then check DCD condition; but, DCD lead is not wired */
#if 0
                if ((sc->sc_flags & TIOCFLAG_SOFTCAR)
                    || (tp->t_cflag & MDMBUF)
                    || (getsiocsr(sc->sc_ctl) & RR_DCD))
                        tp->t_state |= TS_CARR_ON;
                else
                        tp->t_state &= ~TS_CARR_ON;
#else
                tp->t_state |= TS_CARR_ON; /* assume detected all the time */
#endif
                s = spltty();
                sc->sc_rbput = sc->sc_rbget = sc->sc_rbuf;
                sc->sc_rbavail = siotty_rbuf_size;
                splx(s);
        }

        return (*linesw[tp->t_line].l_open)(dev, tp, p);
}
 
int
sioclose(dev_t dev, int flag, int mode, struct proc *p)
{
        struct siotty_softc *sc = siotty_cd.cd_devs[minor(dev)];
        struct tty *tp = sc->sc_tty;
        int s;

        (*linesw[tp->t_line].l_close)(tp, flag, p);

        s = spltty();
        siomctl(sc, TIOCM_BREAK, DMBIC);
#if 0 /* because unable to feed DTR signal */
        if ((tp->t_cflag & HUPCL)
            || tp->t_wopen || (tp->t_state & TS_ISOPEN) == 0) {
                siomctl(sc, TIOCM_DTR, DMBIC);
                /* Yield CPU time to others for 1 second, then ... */
                siomctl(sc, TIOCM_DTR, DMBIS);
        }
#endif
        splx(s);
        return ttyclose(tp);
}
 
int
sioread(dev_t dev, struct uio *uio, int flag)
{
        struct siotty_softc *sc = siotty_cd.cd_devs[minor(dev)];
        struct tty *tp = sc->sc_tty;
 
        return (*linesw[tp->t_line].l_read)(tp, uio, flag);
}
 
int
siowrite(dev_t dev, struct uio *uio, int flag)
{
        struct siotty_softc *sc = siotty_cd.cd_devs[minor(dev)];
        struct tty *tp = sc->sc_tty;
 
        return (*linesw[tp->t_line].l_write)(tp, uio, flag);
}

int
sioioctl(dev_t dev, u_long cmd, caddr_t data, int flag, struct proc *p)
{
        struct siotty_softc *sc = siotty_cd.cd_devs[minor(dev)];
        struct tty *tp = sc->sc_tty;
        int error;

        error = (*linesw[tp->t_line].l_ioctl)(tp, cmd, data, flag, p);
        if (error >= 0)
                return error;

        error = ttioctl(tp, cmd, data, flag, p);
        if (error >= 0)
                return error;

        /* the last resort for TIOC ioctl traversing */
        switch (cmd) {
        case TIOCSBRK: /* Set the hardware into BREAK condition */
                siomctl(sc, TIOCM_BREAK, DMBIS);
                break;
        case TIOCCBRK: /* Clear the hardware BREAK condition */
                siomctl(sc, TIOCM_BREAK, DMBIC);
                break;
        case TIOCSDTR: /* Assert DTR signal */
                siomctl(sc, TIOCM_DTR|TIOCM_RTS, DMBIS);
                break;
        case TIOCCDTR: /* Clear DTR signal */
                siomctl(sc, TIOCM_DTR|TIOCM_RTS, DMBIC);
                break;
        case TIOCMSET: /* Set modem state replacing current one */
                siomctl(sc, *(int *)data, DMSET);
                break;
        case TIOCMGET: /* Return current modem state */
                *(int *)data = siomctl(sc, 0, DMGET);
                break;
        case TIOCMBIS: /* Set individual bits of modem state */
                siomctl(sc, *(int *)data, DMBIS);
                break;
        case TIOCMBIC: /* Clear individual bits of modem state */
                siomctl(sc, *(int *)data, DMBIC);
                break;
        case TIOCSFLAGS: /* Instruct how serial port behaves */
                error = suser(p);
                if (error != 0)
                        return EPERM;
                sc->sc_flags = *(int *)data;
                break;
        case TIOCGFLAGS: /* Return current serial port state */
                *(int *)data = sc->sc_flags;
                break;
        default:
                return ENOTTY;
        }
        return 0;
}

/* ARSGUSED */
struct tty *
siotty(dev_t dev)
{
        struct siotty_softc *sc = siotty_cd.cd_devs[minor(dev)];
 
        return sc->sc_tty;
}

/*--------------------  miscellaneous routines --------------------*/

/* EXPORT */ void
setsioreg(struct sioreg *sio, int regno, int val)
{
        if (regno != 0)
                sio->sio_cmd = regno;   /* DELAY(); */
        sio->sio_cmd = val;             /* DELAY(); */
}

/* EXPORT */ int
getsiocsr(struct sioreg *sio)
{
        int val;

        val = sio->sio_stat << 8;       /* DELAY(); */
        sio->sio_cmd = 1;               /* DELAY(); */
        val |= sio->sio_stat;           /* DELAY(); */
        return val;
}

/*---------------------  console interface ----------------------*/

void syscnattach(int);
int  syscngetc(dev_t);
void syscnputc(dev_t, int);

struct consdev syscons = {
        NULL,
        NULL,
        syscngetc,
        syscnputc,
        nullcnpollc,
        NULL,
        NODEV,
        CN_HIGHPRI,
};

/* EXPORT */ void
syscnattach(int channel)
{
/*
 * Channel A is immediately initialized with 9600N1 right after cold
 * boot/reset/poweron.  ROM monitor emits one line message on CH.A.
 */
        struct sioreg *sio;
        sio = (struct sioreg *)OBIO_SIO + channel;

        syscons.cn_dev = makedev(12, channel);
        cn_tab = &syscons;

        setsioreg(sio, WR0, WR0_CHANRST);
        setsioreg(sio, WR2A, WR2_VEC86 | WR2_INTR_1);
        setsioreg(sio, WR2B, 0);
        setsioreg(sio, WR0, ch0_regs[WR0]);
        setsioreg(sio, WR4, ch0_regs[WR4]);
        setsioreg(sio, WR3, ch0_regs[WR3]);
        setsioreg(sio, WR5, ch0_regs[WR5]);
        setsioreg(sio, WR0, ch0_regs[WR0]);
}

/* EXPORT */ int
syscngetc(dev_t dev)
{
        struct sioreg *sio;
        int s, c;

        sio = (struct sioreg *)OBIO_SIO + ((int)dev & 0x1);
        s = splhigh();
        while ((getsiocsr(sio) & RR_RXRDY) == 0)
                ;
        c = sio->sio_data;
        splx(s);

        return c;
}

/* EXPORT */ void
syscnputc(dev_t dev, int c)
{
        struct sioreg *sio;
        int s;

        sio = (struct sioreg *)OBIO_SIO + ((int)dev & 0x1);
        s = splhigh();
        while ((getsiocsr(sio) & RR_TXRDY) == 0)
                ;
        sio->sio_cmd = WR0_RSTPEND;
        sio->sio_data = c;
        splx(s);
}