Allow pluart(4) to attach to acpi(4).

ok mlarkin@, patrick@

1 files changed, 820 insertions, 0 deletions

diff --git a/sys/dev/ic/pluart.c b/sys/dev/ic/pluart.c
new file mode 100644
index 00000000000..8f42a3f930c
--- /dev/null
+++ b/sys/dev/ic/pluart.c
@@ -0,0 +1,820 @@
+/*	$OpenBSD: pluart.c,v 1.1 2018/07/02 12:46:20 kettenis Exp $	*/
+/*
+ * Copyright (c) 2014 Patrick Wildt <patrick@blueri.se>
+ * Copyright (c) 2005 Dale Rahn <drahn@dalerahn.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/select.h>
+#include <sys/kernel.h>
+
+#include <machine/bus.h>
+
+#include <dev/ic/pluartvar.h>
+#include <dev/cons.h>
+
+#ifdef DDB
+#include <ddb/db_var.h>
+#endif
+
+#define DEVUNIT(x)      (minor(x) & 0x7f)
+#define DEVCUA(x)       (minor(x) & 0x80)
+
+#define UART_DR			0x00		/* Data register */
+#define UART_DR_DATA(x)		((x) & 0xf)
+#define UART_DR_FE		(1 << 8)	/* Framing error */
+#define UART_DR_PE		(1 << 9)	/* Parity error */
+#define UART_DR_BE		(1 << 10)	/* Break error */
+#define UART_DR_OE		(1 << 11)	/* Overrun error */
+#define UART_RSR		0x04		/* Receive status register */
+#define UART_RSR_FE		(1 << 0)	/* Framing error */
+#define UART_RSR_PE		(1 << 1)	/* Parity error */
+#define UART_RSR_BE		(1 << 2)	/* Break error */
+#define UART_RSR_OE		(1 << 3)	/* Overrun error */
+#define UART_ECR		0x04		/* Error clear register */
+#define UART_ECR_FE		(1 << 0)	/* Framing error */
+#define UART_ECR_PE		(1 << 1)	/* Parity error */
+#define UART_ECR_BE		(1 << 2)	/* Break error */
+#define UART_ECR_OE		(1 << 3)	/* Overrun error */
+#define UART_FR			0x18		/* Flag register */
+#define UART_FR_CTS		(1 << 0)	/* Clear to send */
+#define UART_FR_DSR		(1 << 1)	/* Data set ready */
+#define UART_FR_DCD		(1 << 2)	/* Data carrier detect */
+#define UART_FR_BUSY		(1 << 3)	/* UART busy */
+#define UART_FR_RXFE		(1 << 4)	/* Receive FIFO empty */
+#define UART_FR_TXFF		(1 << 5)	/* Transmit FIFO full */
+#define UART_FR_RXFF		(1 << 6)	/* Receive FIFO full */
+#define UART_FR_TXFE		(1 << 7)	/* Transmit FIFO empty */
+#define UART_FR_RI		(1 << 8)	/* Ring indicator */
+#define UART_ILPR		0x20		/* IrDA low-power counter register */
+#define UART_ILPR_ILPDVSR	((x) & 0xf)	/* IrDA low-power divisor */
+#define UART_IBRD		0x24		/* Integer baud rate register */
+#define UART_IBRD_DIVINT	((x) & 0xff)	/* Integer baud rate divisor */
+#define UART_FBRD		0x28		/* Fractional baud rate register */
+#define UART_FBRD_DIVFRAC	((x) & 0x3f)	/* Fractional baud rate divisor */
+#define UART_LCR_H		0x2c		/* Line control register */
+#define UART_LCR_H_BRK		(1 << 0)	/* Send break */
+#define UART_LCR_H_PEN		(1 << 1)	/* Parity enable */
+#define UART_LCR_H_EPS		(1 << 2)	/* Even parity select */
+#define UART_LCR_H_STP2		(1 << 3)	/* Two stop bits select */
+#define UART_LCR_H_FEN		(1 << 4)	/* Enable FIFOs */
+#define UART_LCR_H_WLEN5	(0x0 << 5)	/* Word length: 5 bits */
+#define UART_LCR_H_WLEN6	(0x1 << 5)	/* Word length: 6 bits */
+#define UART_LCR_H_WLEN7	(0x2 << 5)	/* Word length: 7 bits */
+#define UART_LCR_H_WLEN8	(0x3 << 5)	/* Word length: 8 bits */
+#define UART_LCR_H_SPS		(1 << 7)	/* Stick parity select */
+#define UART_CR			0x30		/* Control register */
+#define UART_CR_UARTEN		(1 << 0)	/* UART enable */
+#define UART_CR_SIREN		(1 << 1)	/* SIR enable */
+#define UART_CR_SIRLP		(1 << 2)	/* IrDA SIR low power mode */
+#define UART_CR_LBE		(1 << 7)	/* Loop back enable */
+#define UART_CR_TXE		(1 << 8)	/* Transmit enable */
+#define UART_CR_RXE		(1 << 9)	/* Receive enable */
+#define UART_CR_DTR		(1 << 10)	/* Data transmit enable */
+#define UART_CR_RTS		(1 << 11)	/* Request to send */
+#define UART_CR_OUT1		(1 << 12)
+#define UART_CR_OUT2		(1 << 13)
+#define UART_CR_CTSE		(1 << 14)	/* CTS hardware flow control enable */
+#define UART_CR_RTSE		(1 << 15)	/* RTS hardware flow control enable */
+#define UART_IFLS		0x34		/* Interrupt FIFO level select register */
+#define UART_IMSC		0x38		/* Interrupt mask set/clear register */
+#define UART_IMSC_RIMIM		(1 << 0)
+#define UART_IMSC_CTSMIM	(1 << 1)
+#define UART_IMSC_DCDMIM	(1 << 2)
+#define UART_IMSC_DSRMIM	(1 << 3)
+#define UART_IMSC_RXIM		(1 << 4)
+#define UART_IMSC_TXIM		(1 << 5)
+#define UART_IMSC_RTIM		(1 << 6)
+#define UART_IMSC_FEIM		(1 << 7)
+#define UART_IMSC_PEIM		(1 << 8)
+#define UART_IMSC_BEIM		(1 << 9)
+#define UART_IMSC_OEIM		(1 << 10)
+#define UART_RIS		0x3c		/* Raw interrupt status register */
+#define UART_MIS		0x40		/* Masked interrupt status register */
+#define UART_ICR		0x44		/* Interrupt clear register */
+#define UART_DMACR		0x48		/* DMA control register */
+#define UART_SPACE		0x100
+
+void pluartcnprobe(struct consdev *cp);
+void pluartcninit(struct consdev *cp);
+int pluartcngetc(dev_t dev);
+void pluartcnputc(dev_t dev, int c);
+void pluartcnpollc(dev_t dev, int on);
+int  pluart_param(struct tty *tp, struct termios *t);
+void pluart_start(struct tty *);
+void pluart_pwroff(struct pluart_softc *sc);
+void pluart_diag(void *arg);
+void pluart_raisedtr(void *arg);
+void pluart_softint(void *arg);
+struct pluart_softc *pluart_sc(dev_t dev);
+
+/* XXX - we imitate 'com' serial ports and take over their entry points */
+/* XXX: These belong elsewhere */
+cdev_decl(com);
+cdev_decl(pluart);
+
+struct cfdriver pluart_cd = {
+	NULL, "pluart", DV_TTY
+};
+
+bus_space_tag_t	pluartconsiot;
+bus_space_handle_t pluartconsioh;
+bus_addr_t	pluartconsaddr;
+tcflag_t	pluartconscflag = TTYDEF_CFLAG;
+int		pluartdefaultrate = B38400;
+
+struct cdevsw pluartdev =
+	cdev_tty_init(3/*XXX NUART */ ,pluart);		/* 12: serial port */
+
+void
+pluart_attach_common(struct pluart_softc *sc, int console)
+{
+	int maj;
+
+	if (console) {
+		/* Locate the major number. */
+		for (maj = 0; maj < nchrdev; maj++)
+			if (cdevsw[maj].d_open == pluartopen)
+				break;
+		cn_tab->cn_dev = makedev(maj, sc->sc_dev.dv_unit);
+
+		printf(": console");
+		SET(sc->sc_hwflags, COM_HW_CONSOLE);
+	}
+
+	timeout_set(&sc->sc_diag_tmo, pluart_diag, sc);
+	timeout_set(&sc->sc_dtr_tmo, pluart_raisedtr, sc);
+	sc->sc_si = softintr_establish(IPL_TTY, pluart_softint, sc);
+
+	if(sc->sc_si == NULL)
+		panic("%s: can't establish soft interrupt.",
+		    sc->sc_dev.dv_xname);
+
+	bus_space_write_4(sc->sc_iot, sc->sc_ioh, UART_IMSC, (UART_IMSC_RXIM | UART_IMSC_TXIM));
+	bus_space_write_4(sc->sc_iot, sc->sc_ioh, UART_ICR, 0x7ff);
+	bus_space_write_4(sc->sc_iot, sc->sc_ioh, UART_LCR_H,
+	    bus_space_read_4(sc->sc_iot, sc->sc_ioh, UART_LCR_H) &
+	    ~UART_LCR_H_FEN);
+
+	printf("\n");
+}
+
+int
+pluart_intr(void *arg)
+{
+	struct pluart_softc *sc = arg;
+	bus_space_tag_t iot = sc->sc_iot;
+	bus_space_handle_t ioh = sc->sc_ioh;
+	struct tty *tp = sc->sc_tty;
+	u_int16_t fr;
+	u_int16_t *p;
+	u_int16_t c;
+
+	bus_space_write_4(iot, ioh, UART_ICR, -1);
+
+	if (sc->sc_tty == NULL)
+		return(0);
+
+	fr = bus_space_read_4(iot, ioh, UART_FR);
+	if (ISSET(fr, UART_FR_TXFE) && 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);
+	}
+
+	if(!ISSET(bus_space_read_4(iot, ioh, UART_FR), UART_FR_RXFF))
+		return 0;
+
+	p = sc->sc_ibufp;
+
+	while (ISSET(bus_space_read_4(iot, ioh, UART_FR), UART_FR_RXFF)) {
+		c = bus_space_read_2(iot, ioh, UART_DR);
+		if (c & UART_DR_BE) {
+#ifdef DDB
+			if (ISSET(sc->sc_hwflags, COM_HW_CONSOLE)) {
+				if (db_console)
+					db_enter();
+				continue;
+			}
+#endif
+			c = 0;
+		}
+		if (p >= sc->sc_ibufend) {
+			sc->sc_floods++;
+			if (sc->sc_errors++ == 0)
+				timeout_add(&sc->sc_diag_tmo, 60 * hz);
+		} else {
+			*p++ = c;
+			if (p == sc->sc_ibufhigh && ISSET(tp->t_cflag, CRTSCTS)) {
+				/* XXX */
+				//CLR(sc->sc_ucr3, IMXUART_CR3_DSR);
+				//bus_space_write_4(iot, ioh, IMXUART_UCR3,
+				//    sc->sc_ucr3);
+			}
+		}
+		/* XXX - msr stuff ? */
+	}
+	sc->sc_ibufp = p;
+
+	softintr_schedule(sc->sc_si);
+
+	return 1;
+}
+
+int
+pluart_param(struct tty *tp, struct termios *t)
+{
+	struct pluart_softc *sc = pluart_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:
+		return EINVAL;
+	case CS6:
+		return EINVAL;
+	case CS7:
+		//CLR(sc->sc_ucr2, IMXUART_CR2_WS);
+		break;
+	case CS8:
+		//SET(sc->sc_ucr2, IMXUART_CR2_WS);
+		break;
+	}
+//	bus_space_write_4(iot, ioh, IMXUART_UCR2, sc->sc_ucr2);
+
+	/*
+	if (ISSET(t->c_cflag, PARENB)) {
+		SET(sc->sc_ucr2, IMXUART_CR2_PREN);
+		bus_space_write_4(iot, ioh, IMXUART_UCR2, sc->sc_ucr2);
+	}
+	*/
+	/* STOPB - XXX */
+	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, "pluartprm", 0);
+			--sc->sc_halt;
+			if (error) {
+				pluart_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 */
+
+	pluart_start(tp);
+
+	return 0;
+}
+
+void
+pluart_start(struct tty *tp)
+{
+	struct pluart_softc *sc = pluart_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 | TS_TIMEOUT | TS_TTSTOP))
+		goto out;
+	if (tp->t_outq.c_cc <= tp->t_lowat) {
+		if (ISSET(tp->t_state, TS_ASLEEP)) {
+			CLR(tp->t_state, TS_ASLEEP);
+			wakeup(&tp->t_outq);
+		}
+		if (tp->t_outq.c_cc == 0)
+			goto out;
+		selwakeup(&tp->t_wsel);
+	}
+	SET(tp->t_state, TS_BUSY);
+
+	if (ISSET(sc->sc_hwflags, COM_HW_FIFO)) {
+		u_char buffer[64];	/* largest fifo */
+		int i, n;
+
+		n = q_to_b(&tp->t_outq, buffer,
+		    min(sc->sc_fifolen, sizeof buffer));
+		for (i = 0; i < n; i++) {
+			bus_space_write_4(iot, ioh, UART_DR, buffer[i]);
+		}
+		bzero(buffer, n);
+	} else if (tp->t_outq.c_cc != 0)
+		bus_space_write_4(iot, ioh, UART_DR, getc(&tp->t_outq));
+
+out:
+	splx(s);
+}
+
+void
+pluart_pwroff(struct pluart_softc *sc)
+{
+}
+
+void
+pluart_diag(void *arg)
+{
+	struct pluart_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
+pluart_raisedtr(void *arg)
+{
+	//struct pluart_softc *sc = arg;
+
+	//SET(sc->sc_ucr3, IMXUART_CR3_DSR); /* XXX */
+	//bus_space_write_4(sc->sc_iot, sc->sc_ioh, IMXUART_UCR3, sc->sc_ucr3);
+}
+
+void
+pluart_softint(void *arg)
+{
+	struct pluart_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 || tp == NULL || !ISSET(tp->t_state, TS_ISOPEN)) {
+		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 + UART_IHIGHWATER;
+	sc->sc_ibufend = sc->sc_ibuf + UART_IBUFSIZE;
+
+#if 0
+	if (ISSET(tp->t_cflag, CRTSCTS) &&
+	    !ISSET(sc->sc_ucr3, IMXUART_CR3_DSR)) {
+		/* XXX */
+		SET(sc->sc_ucr3, IMXUART_CR3_DSR);
+		bus_space_write_4(sc->sc_iot, sc->sc_ioh, IMXUART_UCR3,
+		    sc->sc_ucr3);
+	}
+#endif
+
+	splx(s);
+
+	while (ibufp < ibufend) {
+		c = *ibufp++;
+		/*
+		if (ISSET(c, IMXUART_RX_OVERRUN)) {
+			sc->sc_overflows++;
+			if (sc->sc_errors++ == 0)
+				timeout_add(&sc->sc_diag_tmo, 60 * hz);
+		}
+		*/
+		/* This is ugly, but fast. */
+
+		err = 0;
+		/*
+		if (ISSET(c, IMXUART_RX_PRERR))
+			err |= TTY_PE;
+		if (ISSET(c, IMXUART_RX_FRMERR))
+			err |= TTY_FE;
+		*/
+		c = (c & 0xff) | err;
+		(*linesw[tp->t_line].l_rint)(c, tp);
+	}
+}
+
+int
+pluartopen(dev_t dev, int flag, int mode, struct proc *p)
+{
+	int unit = DEVUNIT(dev);
+	struct pluart_softc *sc;
+	bus_space_tag_t iot;
+	bus_space_handle_t ioh;
+	struct tty *tp;
+	int s;
+	int error = 0;
+
+	if (unit >= pluart_cd.cd_ndevs)
+		return ENXIO;
+	sc = pluart_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 = pluart_start;
+	tp->t_param = pluart_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 = pluartconscflag;
+		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 = pluartdefaultrate;
+
+		s = spltty();
+
+		sc->sc_initialize = 1;
+		pluart_param(tp, &tp->t_termios);
+		ttsetwater(tp);
+		sc->sc_ibufp = sc->sc_ibuf = sc->sc_ibufs[0];
+		sc->sc_ibufhigh = sc->sc_ibuf + UART_IHIGHWATER;
+		sc->sc_ibufend = sc->sc_ibuf + UART_IBUFSIZE;
+
+		iot = sc->sc_iot;
+		ioh = sc->sc_ioh;
+
+#if 0
+		sc->sc_ucr1 = bus_space_read_4(iot, ioh, IMXUART_UCR1);
+		sc->sc_ucr2 = bus_space_read_4(iot, ioh, IMXUART_UCR2);
+		sc->sc_ucr3 = bus_space_read_4(iot, ioh, IMXUART_UCR3);
+		sc->sc_ucr4 = bus_space_read_4(iot, ioh, IMXUART_UCR4);
+
+		/* interrupt after one char on tx/rx */
+		/* reference frequency divider: 1 */
+		bus_space_write_4(iot, ioh, IMXUART_UFCR,
+		    1 << IMXUART_FCR_TXTL_SH |
+		    5 << IMXUART_FCR_RFDIV_SH |
+		    1 << IMXUART_FCR_RXTL_SH);
+
+		bus_space_write_4(iot, ioh, IMXUART_UBIR,
+		    (pluartdefaultrate / 100) - 1);
+
+		/* formula: clk / (rfdiv * 1600) */
+		bus_space_write_4(iot, ioh, IMXUART_UBMR,
+		    (clk_get_rate(sc->sc_clk) * 1000) / 1600);
+
+		SET(sc->sc_ucr1, IMXUART_CR1_EN|IMXUART_CR1_RRDYEN);
+		SET(sc->sc_ucr2, IMXUART_CR2_TXEN|IMXUART_CR2_RXEN);
+		bus_space_write_4(iot, ioh, IMXUART_UCR1, sc->sc_ucr1);
+		bus_space_write_4(iot, ioh, IMXUART_UCR2, sc->sc_ucr2);
+
+		/* sc->sc_mcr = MCR_DTR | MCR_RTS;  XXX */
+		SET(sc->sc_ucr3, IMXUART_CR3_DSR); /* XXX */
+		bus_space_write_4(iot, ioh, IMXUART_UCR3, sc->sc_ucr3);
+#endif
+
+		SET(tp->t_state, TS_CARR_ON); /* XXX */
+
+
+	} else if (ISSET(tp->t_state, TS_XCLUDE) && p->p_ucred->cr_uid != 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, 0);
+				/*
+				 * 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);
+					if (!sc->sc_cua && !ISSET(tp->t_state,
+					    TS_ISOPEN))
+						pluart_pwroff(sc);
+					splx(s);
+					return error;
+				}
+			}
+		}
+	}
+	splx(s);
+	return (*linesw[tp->t_line].l_open)(dev,tp,p);
+}
+
+int
+pluartclose(dev_t dev, int flag, int mode, struct proc *p)
+{
+	int unit = DEVUNIT(dev);
+	struct pluart_softc *sc = pluart_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, IMXUART_CR3_DSR);
+		//bus_space_write_4(iot, ioh, IMXUART_UCR3, sc->sc_ucr3);
+		timeout_add(&sc->sc_dtr_tmo, hz * 2);
+	} else {
+		/* no one else waiting; turn off the uart */
+		pluart_pwroff(sc);
+	}
+	CLR(tp->t_state, TS_BUSY | TS_FLUSH);
+
+	sc->sc_cua = 0;
+	splx(s);
+	ttyclose(tp);
+
+	return 0;
+}
+
+int
+pluartread(dev_t dev, struct uio *uio, int flag)
+{
+	struct tty *tty;
+
+	tty = pluarttty(dev);
+	if (tty == NULL)
+		return ENODEV;
+
+	return((*linesw[tty->t_line].l_read)(tty, uio, flag));
+}
+
+int
+pluartwrite(dev_t dev, struct uio *uio, int flag)
+{
+	struct tty *tty;
+
+	tty = pluarttty(dev);
+	if (tty == NULL)
+		return ENODEV;
+
+	return((*linesw[tty->t_line].l_write)(tty, uio, flag));
+}
+
+int
+pluartioctl( dev_t dev, u_long cmd, caddr_t data, int flag, struct proc *p)
+{
+	struct pluart_softc *sc;
+	struct tty *tp;
+	int error;
+
+	sc = pluart_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:
+		break;
+	case TIOCCDTR:
+		break;
+	case TIOCMSET:
+		break;
+	case TIOCMBIS:
+		break;
+	case TIOCMBIC:
+		break;
+	case TIOCMGET:
+		break;
+	case TIOCGFLAGS:
+		break;
+	case TIOCSFLAGS:
+		error = suser(p);
+		if (error != 0)
+			return(EPERM);
+		break;
+	default:
+		return (ENOTTY);
+	}
+
+	return 0;
+}
+
+int
+pluartstop(struct tty *tp, int flag)
+{
+	return 0;
+}
+
+struct tty *
+pluarttty(dev_t dev)
+{
+	int unit;
+	struct pluart_softc *sc;
+	unit = DEVUNIT(dev);
+	if (unit >= pluart_cd.cd_ndevs)
+		return NULL;
+	sc = (struct pluart_softc *)pluart_cd.cd_devs[unit];
+	if (sc == NULL)
+		return NULL;
+	return sc->sc_tty;
+}
+
+struct pluart_softc *
+pluart_sc(dev_t dev)
+{
+	int unit;
+	struct pluart_softc *sc;
+	unit = DEVUNIT(dev);
+	if (unit >= pluart_cd.cd_ndevs)
+		return NULL;
+	sc = (struct pluart_softc *)pluart_cd.cd_devs[unit];
+	return sc;
+}
+
+
+/* serial console */
+void
+pluartcnprobe(struct consdev *cp)
+{
+}
+
+void
+pluartcninit(struct consdev *cp)
+{
+}
+
+int
+pluartcnattach(bus_space_tag_t iot, bus_addr_t iobase, int rate, tcflag_t cflag)
+{
+	static struct consdev pluartcons = {
+		NULL, NULL, pluartcngetc, pluartcnputc, pluartcnpollc, NULL,
+		NODEV, CN_MIDPRI
+	};
+	int maj;
+
+	if (bus_space_map(iot, iobase, UART_SPACE, 0, &pluartconsioh))
+		return ENOMEM;
+
+	/* Disable FIFO. */
+	bus_space_write_4(iot, pluartconsioh, UART_LCR_H,
+	    bus_space_read_4(iot, pluartconsioh, UART_LCR_H) & ~UART_LCR_H_FEN);
+
+	/* 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 = &pluartcons;
+	cn_tab->cn_dev = makedev(maj, 0);
+	cdevsw[12] = pluartdev;		/* KLUDGE */
+
+	pluartconsiot = iot;
+	pluartconsaddr = iobase;
+	pluartconscflag = cflag;
+
+	return 0;
+}
+
+int
+pluartcngetc(dev_t dev)
+{
+	int c;
+	int s;
+	s = splhigh();
+	while((bus_space_read_4(pluartconsiot, pluartconsioh, UART_FR) &
+	    UART_FR_RXFF) == 0)
+		;
+	c = bus_space_read_4(pluartconsiot, pluartconsioh, UART_DR);
+	splx(s);
+	return c;
+}
+
+void
+pluartcnputc(dev_t dev, int c)
+{
+	int s;
+	s = splhigh();
+	while((bus_space_read_4(pluartconsiot, pluartconsioh, UART_FR) &
+	    UART_FR_TXFE) == 0)
+		;
+	bus_space_write_4(pluartconsiot, pluartconsioh, UART_DR, (uint8_t)c);
+	splx(s);
+}
+
+void
+pluartcnpollc(dev_t dev, int on)
+{
+}