/* $OpenBSD: exuart.c,v 1.13 2025/07/03 21:06:51 kettenis Exp $ */
/*
 * Copyright (c) 2005 Dale Rahn <drahn@motorola.com>
 *
 * Permission to use, copy, modify, and distribute this software for any
 * purpose with or without fee is hereby granted, provided that the above
 * copyright notice and this permission notice appear in all copies.
 *
 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 */

#include <sys/param.h>
#include <sys/ioctl.h>
#include <sys/proc.h>
#include <sys/tty.h>
#include <sys/uio.h>
#include <sys/systm.h>
#include <sys/time.h>
#include <sys/device.h>
#include <sys/syslog.h>
#include <sys/conf.h>
#include <sys/fcntl.h>
#include <sys/kernel.h>

#include <machine/bus.h>
#include <machine/fdt.h>

#include <dev/cons.h>

#ifdef DDB
#include <ddb/db_var.h>
#endif

#include <dev/fdt/exuartreg.h>

#include <dev/ofw/openfirm.h>
#include <dev/ofw/ofw_power.h>
#include <dev/ofw/fdt.h>

#define DEVUNIT(x)      (minor(x) & 0x7f)
#define DEVCUA(x)       (minor(x) & 0x80)

struct exuart_softc {
        struct device   sc_dev;
        bus_space_tag_t sc_iot;
        bus_space_handle_t sc_ioh;
        struct soft_intrhand *sc_si;
        void *sc_irq;
        struct tty      *sc_tty;
        struct timeout  sc_diag_tmo;
        struct timeout  sc_dtr_tmo;

        uint32_t        sc_rx_fifo_cnt_mask;
        uint32_t        sc_rx_fifo_full;
        uint32_t        sc_tx_fifo_full;
        int             sc_type;
#define EXUART_TYPE_EXYNOS      0
#define EXUART_TYPE_S5L         1

        int             sc_fifo;
        int             sc_overflows;
        int             sc_floods;
        int             sc_errors;
        int             sc_halt;
        u_int32_t       sc_ulcon;
        u_int32_t       sc_ucon;
        u_int32_t       sc_ufcon;
        u_int32_t       sc_umcon;
        u_int32_t       sc_uintm;
        u_int8_t        sc_hwflags;
#define COM_HW_NOIEN    0x01
#define COM_HW_FIFO     0x02
#define COM_HW_SIR      0x20
#define COM_HW_CONSOLE  0x40
        u_int8_t        sc_swflags;
#define COM_SW_SOFTCAR  0x01
#define COM_SW_CLOCAL   0x02
#define COM_SW_CRTSCTS  0x04
#define COM_SW_MDMBUF   0x08
#define COM_SW_PPS      0x10

        u_int8_t        sc_initialize;
        u_int8_t        sc_cua;
        u_int16_t       *sc_ibuf, *sc_ibufp, *sc_ibufhigh, *sc_ibufend;
#define EXUART_IBUFSIZE 128
#define EXUART_IHIGHWATER 100
        u_int16_t               sc_ibufs[2][EXUART_IBUFSIZE];
};


int      exuart_match(struct device *, void *, void *);
void     exuart_attach(struct device *, struct device *, void *);

void exuartcnprobe(struct consdev *cp);
void exuartcninit(struct consdev *cp);
int exuartcnattach(bus_space_tag_t iot, bus_addr_t iobase, int rate,
    tcflag_t cflag);
int exuartcngetc(dev_t dev);
void exuartcnputc(dev_t dev, int c);
void exuartcnpollc(dev_t dev, int on);
int  exuart_param(struct tty *tp, struct termios *t);
void exuart_start(struct tty *);
void exuart_diag(void *arg);
void exuart_raisedtr(void *arg);
void exuart_softint(void *arg);
struct exuart_softc *exuart_sc(dev_t dev);

int exuart_intr(void *);
int exuart_s5l_intr(void *);

/* XXX - we imitate 'com' serial ports and take over their entry points */
/* XXX: These belong elsewhere */
cdev_decl(com);
cdev_decl(exuart);

struct cfdriver exuart_cd = {
        NULL, "exuart", DV_TTY
};

const struct cfattach exuart_ca = {
        sizeof(struct exuart_softc), exuart_match, exuart_attach
};

bus_space_tag_t exuartconsiot;
bus_space_handle_t exuartconsioh;
bus_addr_t      exuartconsaddr;
tcflag_t        exuartconscflag = TTYDEF_CFLAG;
int             exuartdefaultrate = B115200;

uint32_t        exuart_rx_fifo_cnt_mask;
uint32_t        exuart_rx_fifo_full;
uint32_t        exuart_tx_fifo_full;

struct cdevsw exuartdev =
        cdev_tty_init(3/*XXX NEXUART */ ,exuart);               /* 12: serial port */

void
exuart_init_cons(void)
{
        struct fdt_reg reg;
        void *node, *root;

        if ((node = fdt_find_cons("apple,s5l-uart")) == NULL &&
            (node = fdt_find_cons("samsung,exynos4210-uart")) == NULL)
                return;

        /* dtb uses serial2, qemu uses serial0 */
        root = fdt_find_node("/");
        if (root == NULL)
                panic("%s: could not get fdt root node", __func__);
        if (fdt_is_compatible(root, "samsung,universal_c210")) {
                if ((node = fdt_find_node("/serial@13800000")) == NULL) {
                        return;
                }
                stdout_node = OF_finddevice("/serial@13800000");
        }

        if (fdt_get_reg(node, 0, &reg))
                return;

        if (fdt_is_compatible(node, "apple,s5l-uart")) {
                exuart_rx_fifo_cnt_mask = EXUART_S5L_UFSTAT_RX_FIFO_CNT_MASK;
                exuart_rx_fifo_full = EXUART_S5L_UFSTAT_RX_FIFO_FULL;
                exuart_tx_fifo_full = EXUART_S5L_UFSTAT_TX_FIFO_FULL;
        } else {
                exuart_rx_fifo_cnt_mask = EXUART_UFSTAT_RX_FIFO_CNT_MASK;
                exuart_rx_fifo_full = EXUART_UFSTAT_RX_FIFO_FULL;
                exuart_tx_fifo_full = EXUART_UFSTAT_TX_FIFO_FULL;
        }

        exuartcnattach(fdt_cons_bs_tag, reg.addr, B115200, TTYDEF_CFLAG);
}

int
exuart_match(struct device *parent, void *self, void *aux)
{
        struct fdt_attach_args *faa = aux;

        return (OF_is_compatible(faa->fa_node, "apple,s5l-uart") ||
            OF_is_compatible(faa->fa_node, "samsung,exynos4210-uart"));
}

void
exuart_attach(struct device *parent, struct device *self, void *aux)
{
        struct exuart_softc *sc = (struct exuart_softc *) self;
        struct fdt_attach_args *faa = aux;
        int maj;

        if (faa->fa_nreg < 1)
                return;

        sc->sc_iot = faa->fa_iot;
        if (bus_space_map(sc->sc_iot, faa->fa_reg[0].addr, faa->fa_reg[0].size,
            0, &sc->sc_ioh))
                panic("%s: bus_space_map failed!", __func__);

        if (stdout_node == faa->fa_node) {
                /* Locate the major number. */
                for (maj = 0; maj < nchrdev; maj++)
                        if (cdevsw[maj].d_open == exuartopen)
                                break;
                cn_tab->cn_dev = makedev(maj, sc->sc_dev.dv_unit);

                printf(": console");
                SET(sc->sc_hwflags, COM_HW_CONSOLE);
        }

        printf("\n");

        power_domain_enable(faa->fa_node);

        if (OF_is_compatible(faa->fa_node, "apple,s5l-uart")) {
                sc->sc_type = EXUART_TYPE_S5L;
                sc->sc_rx_fifo_cnt_mask = EXUART_S5L_UFSTAT_RX_FIFO_CNT_MASK;
                sc->sc_rx_fifo_full = EXUART_S5L_UFSTAT_RX_FIFO_FULL;
                sc->sc_tx_fifo_full = EXUART_S5L_UFSTAT_TX_FIFO_FULL;

                /* Mask and clear interrupts. */
                sc->sc_ucon = bus_space_read_4(sc->sc_iot, sc->sc_ioh,
                    EXUART_UCON);
                CLR(sc->sc_ucon, EXUART_S5L_UCON_RX_TIMEOUT);
                CLR(sc->sc_ucon, EXUART_S5L_UCON_RXTHRESH);
                CLR(sc->sc_ucon, EXUART_S5L_UCON_TXTHRESH);
                bus_space_write_4(sc->sc_iot, sc->sc_ioh, EXUART_UCON,
                    sc->sc_ucon);
                bus_space_write_4(sc->sc_iot, sc->sc_ioh, EXUART_UTRSTAT,
                    EXUART_S5L_UTRSTAT_RX_TIMEOUT |
                    EXUART_S5L_UTRSTAT_RXTHRESH |
                    EXUART_S5L_UTRSTAT_TXTHRESH);

                sc->sc_ucon = bus_space_read_4(sc->sc_iot, sc->sc_ioh,
                    EXUART_UCON);
                SET(sc->sc_ucon, EXUART_UCON_RX_TIMEOUT);
                bus_space_write_4(sc->sc_iot, sc->sc_ioh, EXUART_UCON,
                    sc->sc_ucon);

                sc->sc_irq = fdt_intr_establish(faa->fa_node, IPL_TTY,
                    exuart_s5l_intr, sc, sc->sc_dev.dv_xname);
        } else {
                sc->sc_type = EXUART_TYPE_EXYNOS;
                sc->sc_rx_fifo_cnt_mask = EXUART_UFSTAT_RX_FIFO_CNT_MASK;
                sc->sc_rx_fifo_full = EXUART_UFSTAT_RX_FIFO_FULL;
                sc->sc_tx_fifo_full = EXUART_UFSTAT_TX_FIFO_FULL;

                /* Mask and clear interrupts. */
                bus_space_write_4(sc->sc_iot, sc->sc_ioh, EXUART_UINTM,
                    EXUART_UINTM_RXD | EXUART_UINTM_ERROR |
                    EXUART_UINTM_TXD | EXUART_UINTM_MODEM);
                bus_space_write_4(sc->sc_iot, sc->sc_ioh, EXUART_UINTP,
                    EXUART_UINTP_RXD | EXUART_UINTP_ERROR |
                    EXUART_UINTP_TXD | EXUART_UINTP_MODEM);

                sc->sc_ucon = bus_space_read_4(sc->sc_iot, sc->sc_ioh,
                    EXUART_UCON);
                CLR(sc->sc_ucon, EXUART_UCON_RX_TIMEOUT_EMPTY_FIFO);
                SET(sc->sc_ucon, EXUART_UCON_RX_INT_TYPE_LEVEL);
                SET(sc->sc_ucon, EXUART_UCON_RX_TIMEOUT);
                bus_space_write_4(sc->sc_iot, sc->sc_ioh, EXUART_UCON,
                    sc->sc_ucon);

                sc->sc_irq = fdt_intr_establish(faa->fa_node, IPL_TTY,
                    exuart_intr, sc, sc->sc_dev.dv_xname);
        }

        timeout_set(&sc->sc_diag_tmo, exuart_diag, sc);
        timeout_set(&sc->sc_dtr_tmo, exuart_raisedtr, sc);
        sc->sc_si = softintr_establish(IPL_TTY, exuart_softint, sc);

        if(sc->sc_si == NULL)
                panic("%s: can't establish soft interrupt.",
                    sc->sc_dev.dv_xname);
}

void
exuart_rx_intr(struct exuart_softc *sc)
{
        bus_space_tag_t iot = sc->sc_iot;
        bus_space_handle_t ioh = sc->sc_ioh;
        u_int16_t *p;
        u_int16_t c;

        p = sc->sc_ibufp;

        while (bus_space_read_4(iot, ioh, EXUART_UFSTAT) &
            (sc->sc_rx_fifo_cnt_mask | sc->sc_rx_fifo_full)) {
                c = bus_space_read_4(iot, ioh, EXUART_URXH);
                if (p >= sc->sc_ibufend) {
                        sc->sc_floods++;
                        if (sc->sc_errors++ == 0)
                                timeout_add_sec(&sc->sc_diag_tmo, 60);
                } else {
                        *p++ = c;
#if 0
                        if (p == sc->sc_ibufhigh &&
                            ISSET(tp->t_cflag, CRTSCTS)) {
                                /* XXX */
                        }
#endif
                }
        }

        sc->sc_ibufp = p;

        softintr_schedule(sc->sc_si);
}

void
exuart_tx_intr(struct exuart_softc *sc)
{
        struct tty *tp = sc->sc_tty;

        if (ISSET(tp->t_state, TS_BUSY)) {
                CLR(tp->t_state, TS_BUSY | TS_FLUSH);
                if (sc->sc_halt > 0)
                        wakeup(&tp->t_outq);
                (*linesw[tp->t_line].l_start)(tp);
        }
}

int
exuart_intr(void *arg)
{
        struct exuart_softc *sc = arg;
        bus_space_tag_t iot = sc->sc_iot;
        bus_space_handle_t ioh = sc->sc_ioh;
        u_int32_t uintp;

        uintp = bus_space_read_4(iot, ioh, EXUART_UINTP);
        if (uintp == 0)
                return (0);

        if (sc->sc_tty == NULL)
                return (0);

        if (ISSET(uintp, EXUART_UINTP_RXD)) {
                exuart_rx_intr(sc);
                bus_space_write_4(iot, ioh, EXUART_UINTP, EXUART_UINTP_RXD);
        }

        if (ISSET(uintp, EXUART_UINTP_TXD)) {
                exuart_tx_intr(sc);
                bus_space_write_4(iot, ioh, EXUART_UINTP, EXUART_UINTP_TXD);
        }

#if 0
        if(!ISSET(bus_space_read_2(iot, ioh, EXUART_USR2), EXUART_SR2_RDR))
                return 0;

        p = sc->sc_ibufp;

        while(ISSET(bus_space_read_2(iot, ioh, EXUART_USR2), EXUART_SR2_RDR)) {
                c = bus_space_read_4(iot, ioh, EXUART_URXH);
                if (p >= sc->sc_ibufend) {
                        sc->sc_floods++;
                        if (sc->sc_errors++ == 0)
                                timeout_add_sec(&sc->sc_diag_tmo, 60);
                } else {
                        *p++ = c;
                        if (p == sc->sc_ibufhigh && ISSET(tp->t_cflag, CRTSCTS))
                                /* XXX */
                                //CLR(sc->sc_ucr3, EXUART_CR3_DSR);
                                //bus_space_write_2(iot, ioh, EXUART_UCR3,
                                //    sc->sc_ucr3);

                }
                /* XXX - msr stuff ? */
        }
        sc->sc_ibufp = p;

        softintr_schedule(sc->sc_si);
#endif

        return 1;
}

int
exuart_s5l_intr(void *arg)
{
        struct exuart_softc *sc = arg;
        bus_space_tag_t iot = sc->sc_iot;
        bus_space_handle_t ioh = sc->sc_ioh;
        u_int32_t utrstat, uerstat;

        utrstat = bus_space_read_4(iot, ioh, EXUART_UTRSTAT);
        uerstat = bus_space_read_4(iot, ioh, EXUART_UERSTAT);

        if (sc->sc_tty == NULL)
                return (0);

#ifdef DDB
        if (uerstat & EXUART_UERSTAT_BREAK) {
                if (ISSET(sc->sc_hwflags, COM_HW_CONSOLE)) {
                        if (db_console)
                                db_enter();
                }
        }
#endif

        if (utrstat & (EXUART_S5L_UTRSTAT_RXTHRESH |
            EXUART_S5L_UTRSTAT_RX_TIMEOUT))
                exuart_rx_intr(sc);

        if (utrstat & EXUART_S5L_UTRSTAT_TXTHRESH)
                exuart_tx_intr(sc);

        bus_space_write_4(iot, ioh, EXUART_UTRSTAT, utrstat);

        return 1;
}

int
exuart_param(struct tty *tp, struct termios *t)
{
        struct exuart_softc *sc = exuart_cd.cd_devs[DEVUNIT(tp->t_dev)];
        bus_space_tag_t iot = sc->sc_iot;
        bus_space_handle_t ioh = sc->sc_ioh;
        int ospeed = t->c_ospeed;
        int error;
        tcflag_t oldcflag;


        if (t->c_ospeed < 0 || (t->c_ispeed && t->c_ispeed != t->c_ospeed))
                return EINVAL;

        switch (ISSET(t->c_cflag, CSIZE)) {
        case CS5:
                CLR(sc->sc_ulcon, EXUART_ULCON_WORD_MASK);
                SET(sc->sc_ulcon, EXUART_ULCON_WORD_FIVE);
                break;
        case CS6:
                CLR(sc->sc_ulcon, EXUART_ULCON_WORD_MASK);
                SET(sc->sc_ulcon, EXUART_ULCON_WORD_SIX);
                break;
        case CS7:
                CLR(sc->sc_ulcon, EXUART_ULCON_WORD_MASK);
                SET(sc->sc_ulcon, EXUART_ULCON_WORD_SEVEN);
                break;
        case CS8:
                CLR(sc->sc_ulcon, EXUART_ULCON_WORD_MASK);
                SET(sc->sc_ulcon, EXUART_ULCON_WORD_EIGHT);
                break;
        }

        CLR(sc->sc_ulcon, EXUART_ULCON_PARITY_MASK);
        if (ISSET(t->c_cflag, PARENB)) {
                if (ISSET(t->c_cflag, PARODD))
                        SET(sc->sc_ulcon, EXUART_ULCON_PARITY_ODD);
                else
                        SET(sc->sc_ulcon, EXUART_ULCON_PARITY_EVEN);
        }

        if (ISSET(t->c_cflag, CSTOPB))
                SET(sc->sc_ulcon, EXUART_ULCON_STOP_TWO);
        else
                CLR(sc->sc_ulcon, EXUART_ULCON_STOP_ONE);

        bus_space_write_4(iot, ioh, EXUART_ULCON, sc->sc_ulcon);

        if (ospeed == 0) {
                /* lower dtr */
        }

        if (ospeed != 0) {
                while (ISSET(tp->t_state, TS_BUSY)) {
                        ++sc->sc_halt;
                        error = ttysleep(tp, &tp->t_outq,
                            TTOPRI | PCATCH, "exuartprm");
                        --sc->sc_halt;
                        if (error) {
                                exuart_start(tp);
                                return (error);
                        }
                }
                /* set speed */
        }

        /* setup fifo */

        /* When not using CRTSCTS, RTS follows DTR. */
        /* sc->sc_dtr = MCR_DTR; */


        /* and copy to tty */
        tp->t_ispeed = t->c_ispeed;
        tp->t_ospeed = t->c_ospeed;
        oldcflag = tp->t_cflag;
        tp->t_cflag = t->c_cflag;

        /*
         * If DCD is off and MDMBUF is changed, ask the tty layer if we should
         * stop the device.
         */
         /* XXX */

        exuart_start(tp);

        return 0;
}

void
exuart_start(struct tty *tp)
{
        struct exuart_softc *sc = exuart_cd.cd_devs[DEVUNIT(tp->t_dev)];
        bus_space_tag_t iot = sc->sc_iot;
        bus_space_handle_t ioh = sc->sc_ioh;
        int s;

        s = spltty();
        if (ISSET(tp->t_state, TS_BUSY))
                goto out;
        if (ISSET(tp->t_state, TS_TIMEOUT | TS_TTSTOP) || sc->sc_halt > 0)
                goto stopped;
#ifdef DAMNFUCKSHIT
        /* clear to send (IE the RTS pin on this shit) is not directly \
         * readable - skip check for now
         */
        if (ISSET(tp->t_cflag, CRTSCTS) && !ISSET(sc->sc_msr, EXUART_CTS))
                goto stopped;
#endif
        ttwakeupwr(tp);
        if (tp->t_outq.c_cc == 0)
                goto stopped;
        SET(tp->t_state, TS_BUSY);

        {
                u_char buffer[16];
                int i, n;

                n = q_to_b(&tp->t_outq, buffer, sizeof buffer);
                for (i = 0; i < n; i++)
                        bus_space_write_4(iot, ioh, EXUART_UTXH, buffer[i]);
                bzero(buffer, n);
        }

        if (sc->sc_type == EXUART_TYPE_S5L) {
                if (!ISSET(sc->sc_ucon, EXUART_S5L_UCON_TXTHRESH)) {
                        SET(sc->sc_ucon, EXUART_S5L_UCON_TXTHRESH);
                        bus_space_write_4(iot, ioh, EXUART_UCON, sc->sc_ucon);
                }
        } else {
                if (ISSET(sc->sc_uintm, EXUART_UINTM_TXD)) {
                        CLR(sc->sc_uintm, EXUART_UINTM_TXD);
                        bus_space_write_4(iot, ioh, EXUART_UINTM, sc->sc_uintm);
                }
        }

out:
        splx(s);
        return;
stopped:
        if (sc->sc_type == EXUART_TYPE_S5L) {
                if (ISSET(sc->sc_ucon, EXUART_S5L_UCON_TXTHRESH)) {
                        CLR(sc->sc_ucon, EXUART_S5L_UCON_TXTHRESH);
                        bus_space_write_4(iot, ioh, EXUART_UCON, sc->sc_ucon);
                }
        } else {
                if (!ISSET(sc->sc_uintm, EXUART_UINTM_TXD)) {
                        SET(sc->sc_uintm, EXUART_UINTM_TXD);
                        bus_space_write_4(iot, ioh, EXUART_UINTM, sc->sc_uintm);
                }
        }
        splx(s);
}

void
exuart_diag(void *arg)
{
        struct exuart_softc *sc = arg;
        int overflows, floods;
        int s;

        s = spltty();
        sc->sc_errors = 0;
        overflows = sc->sc_overflows;
        sc->sc_overflows = 0;
        floods = sc->sc_floods;
        sc->sc_floods = 0;
        splx(s);
        log(LOG_WARNING, "%s: %d silo overflow%s, %d ibuf overflow%s\n",
            sc->sc_dev.dv_xname,
            overflows, overflows == 1 ? "" : "s",
            floods, floods == 1 ? "" : "s");
}

void
exuart_raisedtr(void *arg)
{
        //struct exuart_softc *sc = arg;

        //SET(sc->sc_ucr3, EXUART_CR3_DSR); /* XXX */
        //bus_space_write_2(sc->sc_iot, sc->sc_ioh, EXUART_UCR3, sc->sc_ucr3);
}

void
exuart_softint(void *arg)
{
        struct exuart_softc *sc = arg;
        struct tty *tp;
        u_int16_t *ibufp;
        u_int16_t *ibufend;
        int c;
        int err;
        int s;

        if (sc == NULL || sc->sc_ibufp == sc->sc_ibuf)
                return;

        tp = sc->sc_tty;

        s = spltty();

        ibufp = sc->sc_ibuf;
        ibufend = sc->sc_ibufp;

        if (ibufp == ibufend) {
                splx(s);
                return;
        }

        sc->sc_ibufp = sc->sc_ibuf = (ibufp == sc->sc_ibufs[0]) ?
            sc->sc_ibufs[1] : sc->sc_ibufs[0];
        sc->sc_ibufhigh = sc->sc_ibuf + EXUART_IHIGHWATER;
        sc->sc_ibufend = sc->sc_ibuf + EXUART_IBUFSIZE;

        if (tp == NULL || !ISSET(tp->t_state, TS_ISOPEN)) {
                splx(s);
                return;
        }

#if 0
        if (ISSET(tp->t_cflag, CRTSCTS) &&
            !ISSET(sc->sc_ucr3, EXUART_CR3_DSR)) {
                /* XXX */
                SET(sc->sc_ucr3, EXUART_CR3_DSR);
                bus_space_write_2(sc->sc_iot, sc->sc_ioh, EXUART_UCR3,
                    sc->sc_ucr3);
        }
#endif

        splx(s);

        while (ibufp < ibufend) {
                c = *ibufp++;
#if 0
                if (ISSET(c, EXUART_UERSTAT_OVERRUN)) {
                        sc->sc_overflows++;
                        if (sc->sc_errors++ == 0)
                                timeout_add_sec(&sc->sc_diag_tmo, 60);
                }
#endif
                err = 0;
#if 0
                if (ISSET(c, EXUART_UERSTAT_PARITY))
                        err |= TTY_PE;
                if (ISSET(c, EXUART_UERSTAT_FRAME))
                        err |= TTY_FE;
#endif
                c = (c & 0xff) | err;
                (*linesw[tp->t_line].l_rint)(c, tp);
        }
}

int
exuartopen(dev_t dev, int flag, int mode, struct proc *p)
{
        int unit = DEVUNIT(dev);
        struct exuart_softc *sc;
        bus_space_tag_t iot;
        bus_space_handle_t ioh;
        struct tty *tp;
        int s;
        int error = 0;

        if (unit >= exuart_cd.cd_ndevs)
                return ENXIO;
        sc = exuart_cd.cd_devs[unit];
        if (sc == NULL)
                return ENXIO;

        s = spltty();
        if (sc->sc_tty == NULL)
                tp = sc->sc_tty = ttymalloc(0);
        else
                tp = sc->sc_tty;
        splx(s);

        tp->t_oproc = exuart_start;
        tp->t_param = exuart_param;
        tp->t_dev = dev;
        if (!ISSET(tp->t_state, TS_ISOPEN)) {
                SET(tp->t_state, TS_WOPEN);
                ttychars(tp);
                tp->t_iflag = TTYDEF_IFLAG;
                tp->t_oflag = TTYDEF_OFLAG;

                if (ISSET(sc->sc_hwflags, COM_HW_CONSOLE))
                        tp->t_cflag = exuartconscflag;
                else
                        tp->t_cflag = TTYDEF_CFLAG;
                if (ISSET(sc->sc_swflags, COM_SW_CLOCAL))
                        SET(tp->t_cflag, CLOCAL);
                if (ISSET(sc->sc_swflags, COM_SW_CRTSCTS))
                        SET(tp->t_cflag, CRTSCTS);
                if (ISSET(sc->sc_swflags, COM_SW_MDMBUF))
                        SET(tp->t_cflag, MDMBUF);
                tp->t_lflag = TTYDEF_LFLAG;
                tp->t_ispeed = tp->t_ospeed = exuartdefaultrate;

                s = spltty();

                sc->sc_initialize = 1;
                exuart_param(tp, &tp->t_termios);
                ttsetwater(tp);

                sc->sc_ibufp = sc->sc_ibuf = sc->sc_ibufs[0];
                sc->sc_ibufhigh = sc->sc_ibuf + EXUART_IHIGHWATER;
                sc->sc_ibufend = sc->sc_ibuf + EXUART_IBUFSIZE;

                iot = sc->sc_iot;
                ioh = sc->sc_ioh;

                sc->sc_ulcon = bus_space_read_4(iot, ioh, EXUART_ULCON);
                sc->sc_ucon = bus_space_read_4(iot, ioh, EXUART_UCON);
                sc->sc_ufcon = bus_space_read_4(iot, ioh, EXUART_UFCON);
                sc->sc_umcon = bus_space_read_4(iot, ioh, EXUART_UMCON);

                if (sc->sc_type == EXUART_TYPE_S5L) {
                        SET(sc->sc_ucon, EXUART_UCON_RX_TIMEOUT);
                        SET(sc->sc_ucon, EXUART_S5L_UCON_RXTHRESH);
                        SET(sc->sc_ucon, EXUART_S5L_UCON_RX_TIMEOUT);
                        bus_space_write_4(iot, ioh, EXUART_UCON, sc->sc_ucon);
                } else {
                        sc->sc_uintm = bus_space_read_4(iot, ioh, EXUART_UINTM);
                        CLR(sc->sc_uintm, EXUART_UINTM_RXD);
                        bus_space_write_4(iot, ioh, EXUART_UINTM, sc->sc_uintm);
                }

#if 0
                /* interrupt after one char on tx/rx */
                /* reference frequency divider: 1 */
                bus_space_write_2(iot, ioh, EXUART_UFCR,
                    1 << EXUART_FCR_TXTL_SH |
                    5 << EXUART_FCR_RFDIV_SH |
                    1 << EXUART_FCR_RXTL_SH);

                bus_space_write_2(iot, ioh, EXUART_UBIR,
                    (exuartdefaultrate / 100) - 1);

                /* formula: clk / (rfdiv * 1600) */
                bus_space_write_2(iot, ioh, EXUART_UBMR,
                    (exccm_get_uartclk() * 1000) / 1600);

                SET(sc->sc_ucr1, EXUART_CR1_EN|EXUART_CR1_RRDYEN);
                SET(sc->sc_ucr2, EXUART_CR2_TXEN|EXUART_CR2_RXEN);
                bus_space_write_2(iot, ioh, EXUART_UCR1, sc->sc_ucr1);
                bus_space_write_2(iot, ioh, EXUART_UCR2, sc->sc_ucr2);

                /* sc->sc_mcr = MCR_DTR | MCR_RTS;  XXX */
                SET(sc->sc_ucr3, EXUART_CR3_DSR); /* XXX */
                bus_space_write_2(iot, ioh, EXUART_UCR3, sc->sc_ucr3);
#endif

                SET(tp->t_state, TS_CARR_ON); /* XXX */


        } else if (ISSET(tp->t_state, TS_XCLUDE) && suser(p) != 0)
                return EBUSY;
        else
                s = spltty();

        if (DEVCUA(dev)) {
                if (ISSET(tp->t_state, TS_ISOPEN)) {
                        splx(s);
                        return EBUSY;
                }
                sc->sc_cua = 1;
        } else {
                /* tty (not cua) device; wait for carrier if necessary */
                if (ISSET(flag, O_NONBLOCK)) {
                        if (sc->sc_cua) {
                                /* Opening TTY non-blocking... but the CUA is busy */
                                splx(s);
                                return EBUSY;
                        }
                } else {
                        while (sc->sc_cua ||
                            (!ISSET(tp->t_cflag, CLOCAL) &&
                                !ISSET(tp->t_state, TS_CARR_ON))) {
                                SET(tp->t_state, TS_WOPEN);
                                error = ttysleep(tp, &tp->t_rawq,
                                    TTIPRI | PCATCH, ttopen);
                                /*
                                 * If TS_WOPEN has been reset, that means the
                                 * cua device has been closed.  We don't want
                                 * to fail in that case,
                                 * so just go around again.
                                 */
                                if (error && ISSET(tp->t_state, TS_WOPEN)) {
                                        CLR(tp->t_state, TS_WOPEN);
                                        splx(s);
                                        return error;
                                }
                        }
                }
        }
        splx(s);

        return (*linesw[tp->t_line].l_open)(dev,tp,p);
}

int
exuartclose(dev_t dev, int flag, int mode, struct proc *p)
{
        int unit = DEVUNIT(dev);
        struct exuart_softc *sc = exuart_cd.cd_devs[unit];
        //bus_space_tag_t iot = sc->sc_iot;
        //bus_space_handle_t ioh = sc->sc_ioh;
        struct tty *tp = sc->sc_tty;
        int s;

        /* XXX This is for cons.c. */
        if (!ISSET(tp->t_state, TS_ISOPEN))
                return 0;

        (*linesw[tp->t_line].l_close)(tp, flag, p);
        s = spltty();
        if (ISSET(tp->t_state, TS_WOPEN)) {
                /* tty device is waiting for carrier; drop dtr then re-raise */
                //CLR(sc->sc_ucr3, EXUART_CR3_DSR);
                //bus_space_write_2(iot, ioh, EXUART_UCR3, sc->sc_ucr3);
                timeout_add_sec(&sc->sc_dtr_tmo, 2);
        }
        CLR(tp->t_state, TS_BUSY | TS_FLUSH);
        sc->sc_cua = 0;
        splx(s);
        ttyclose(tp);

        return 0;
}

int
exuartread(dev_t dev, struct uio *uio, int flag)
{
        struct tty *tty;

        tty = exuarttty(dev);
        if (tty == NULL)
                return ENODEV;

        return((*linesw[tty->t_line].l_read)(tty, uio, flag));
}

int
exuartwrite(dev_t dev, struct uio *uio, int flag)
{
        struct tty *tty;

        tty = exuarttty(dev);
        if (tty == NULL)
                return ENODEV;

        return((*linesw[tty->t_line].l_write)(tty, uio, flag));
}

int
exuartioctl( dev_t dev, u_long cmd, caddr_t data, int flag, struct proc *p)
{
        struct exuart_softc *sc;
        struct tty *tp;
        int error;

        sc = exuart_sc(dev);
        if (sc == NULL)
                return (ENODEV);

        tp = sc->sc_tty;
        if (tp == NULL)
                return (ENXIO);

        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);

        switch(cmd) {
        case TIOCSBRK:
                /* */
                break;

        case TIOCCBRK:
                /* */
                break;

        case TIOCSDTR:
#if 0
                (void) clmctl(dev, TIOCM_DTR | TIOCM_RTS, DMBIS);
#endif
                break;

        case TIOCCDTR:
#if 0
                (void) clmctl(dev, TIOCM_DTR | TIOCM_RTS, DMBIC);
#endif
                break;

        case TIOCMSET:
#if 0
                (void) clmctl(dev, *(int *) data, DMSET);
#endif
                break;

        case TIOCMBIS:
#if 0
                (void) clmctl(dev, *(int *) data, DMBIS);
#endif
                break;

        case TIOCMBIC:
#if 0
                (void) clmctl(dev, *(int *) data, DMBIC);
#endif
                break;

        case TIOCMGET:
#if 0
                *(int *)data = clmctl(dev, 0, DMGET);
#endif
                break;

        case TIOCGFLAGS:
#if 0
                *(int *)data = cl->cl_swflags;
#endif
                break;

        case TIOCSFLAGS:
                error = suser(p);
                if (error != 0)
                        return(EPERM);

#if 0
                cl->cl_swflags = *(int *)data;
                cl->cl_swflags &= /* only allow valid flags */
                    (TIOCFLAG_SOFTCAR | TIOCFLAG_CLOCAL | TIOCFLAG_CRTSCTS);
#endif
                break;
        default:
                return (ENOTTY);
        }

        return 0;
}

int
exuartstop(struct tty *tp, int flag)
{
        return 0;
}

struct tty *
exuarttty(dev_t dev)
{
        int unit;
        struct exuart_softc *sc;
        unit = DEVUNIT(dev);
        if (unit >= exuart_cd.cd_ndevs)
                return NULL;
        sc = (struct exuart_softc *)exuart_cd.cd_devs[unit];
        if (sc == NULL)
                return NULL;
        return sc->sc_tty;
}

struct exuart_softc *
exuart_sc(dev_t dev)
{
        int unit;
        struct exuart_softc *sc;
        unit = DEVUNIT(dev);
        if (unit >= exuart_cd.cd_ndevs)
                return NULL;
        sc = (struct exuart_softc *)exuart_cd.cd_devs[unit];
        return sc;
}


/* serial console */
void
exuartcnprobe(struct consdev *cp)
{
}

void
exuartcninit(struct consdev *cp)
{
}

int
exuartcnattach(bus_space_tag_t iot, bus_addr_t iobase, int rate, tcflag_t cflag)
{
        static struct consdev exuartcons = {
                NULL, NULL, exuartcngetc, exuartcnputc, exuartcnpollc, NULL,
                NODEV, CN_MIDPRI
        };
        int maj;

        if (bus_space_map(iot, iobase, 0x100, 0, &exuartconsioh))
                return ENOMEM;

        /* Look for major of com(4) to replace. */
        for (maj = 0; maj < nchrdev; maj++)
                if (cdevsw[maj].d_open == comopen)
                        break;
        if (maj == nchrdev)
                return ENXIO;

        cn_tab = &exuartcons;
        cn_tab->cn_dev = makedev(maj, 0);
        cdevsw[maj] = exuartdev;        /* KLUDGE */

        exuartconsiot = iot;
        exuartconsaddr = iobase;
        exuartconscflag = cflag;

        return 0;
}

int
exuartcngetc(dev_t dev)
{
        int c;
        int s;
        s = splhigh();
        while((bus_space_read_4(exuartconsiot, exuartconsioh, EXUART_UTRSTAT) &
            EXUART_UTRSTAT_RXBREADY) == 0 &&
              (bus_space_read_4(exuartconsiot, exuartconsioh, EXUART_UFSTAT) &
            (exuart_rx_fifo_cnt_mask | exuart_rx_fifo_full)) == 0)
                ;
        c = bus_space_read_4(exuartconsiot, exuartconsioh, EXUART_URXH);
        splx(s);
        return c;
}

void
exuartcnputc(dev_t dev, int c)
{
        int s;
        s = splhigh();
        while (bus_space_read_4(exuartconsiot, exuartconsioh, EXUART_UFSTAT) &
           exuart_tx_fifo_full)
                ;
        bus_space_write_4(exuartconsiot, exuartconsioh, EXUART_UTXH, c);
        splx(s);
}

void
exuartcnpollc(dev_t dev, int on)
{
}