xref: /openbsd-src/sys/arch/sh/dev/scif.c (revision 897fc685943471cf985a0fe38ba076ea6fe74fa5)
1 /*	$OpenBSD: scif.c,v 1.19 2018/02/19 08:59:52 mpi Exp $	*/
2 /*	$NetBSD: scif.c,v 1.47 2006/07/23 22:06:06 ad Exp $ */
3 
4 /*-
5  * Copyright (C) 1999 T.Horiuchi and SAITOH Masanobu.  All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  * 3. The name of the author may not be used to endorse or promote products
16  *    derived from this software without specific prior written permission.
17  *
18  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
19  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
20  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
21  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
22  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
23  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
24  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
25  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
26  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
27  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
28  */
29 
30 /*-
31  * Copyright (c) 1998, 1999 The NetBSD Foundation, Inc.
32  * All rights reserved.
33  *
34  * This code is derived from software contributed to The NetBSD Foundation
35  * by Charles M. Hannum.
36  *
37  * Redistribution and use in source and binary forms, with or without
38  * modification, are permitted provided that the following conditions
39  * are met:
40  * 1. Redistributions of source code must retain the above copyright
41  *    notice, this list of conditions and the following disclaimer.
42  * 2. Redistributions in binary form must reproduce the above copyright
43  *    notice, this list of conditions and the following disclaimer in the
44  *    documentation and/or other materials provided with the distribution.
45  *
46  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
47  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
48  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
49  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
50  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
51  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
52  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
53  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
54  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
55  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
56  * POSSIBILITY OF SUCH DAMAGE.
57  */
58 
59 /*
60  * Copyright (c) 1991 The Regents of the University of California.
61  * All rights reserved.
62  *
63  * Redistribution and use in source and binary forms, with or without
64  * modification, are permitted provided that the following conditions
65  * are met:
66  * 1. Redistributions of source code must retain the above copyright
67  *    notice, this list of conditions and the following disclaimer.
68  * 2. Redistributions in binary form must reproduce the above copyright
69  *    notice, this list of conditions and the following disclaimer in the
70  *    documentation and/or other materials provided with the distribution.
71  * 3. Neither the name of the University nor the names of its contributors
72  *    may be used to endorse or promote products derived from this software
73  *    without specific prior written permission.
74  *
75  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
76  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
77  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
78  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
79  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
80  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
81  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
82  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
83  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
84  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
85  * SUCH DAMAGE.
86  *
87  *	@(#)com.c	7.5 (Berkeley) 5/16/91
88  */
89 
90 /*
91  * SH internal serial driver
92  *
93  * This code is derived from both z8530tty.c and com.c
94  */
95 
96 #include <sys/param.h>
97 #include <sys/systm.h>
98 #include <sys/tty.h>
99 #include <sys/proc.h>
100 #include <sys/conf.h>
101 #include <sys/syslog.h>
102 #include <sys/kernel.h>
103 #include <sys/device.h>
104 #include <sys/malloc.h>
105 #include <sys/timeout.h>
106 
107 #include <dev/cons.h>
108 
109 #include <sh/clock.h>
110 #include <sh/trap.h>
111 #include <machine/intr.h>
112 #include <machine/conf.h>
113 
114 #include <sh/dev/scifreg.h>
115 
116 #ifdef DDB
117 #include <ddb/db_var.h>
118 #endif
119 
120 void	scifstart(struct tty *);
121 int	scifparam(struct tty *, struct termios *);
122 
123 cons_decl(scif);
124 void scif_intr_init(void);
125 int scifintr(void *);
126 
127 struct scif_softc {
128 	struct device sc_dev;		/* boilerplate */
129 	struct tty *sc_tty;
130 	void *sc_si;
131 
132 	struct timeout sc_diag_tmo;
133 
134 #if 0
135 	bus_space_tag_t sc_iot;		/* ISA i/o space identifier */
136 	bus_space_handle_t   sc_ioh;	/* ISA io handle */
137 
138 	int sc_drq;
139 
140 	int sc_frequency;
141 #endif
142 
143 	u_int sc_overflows,
144 	      sc_floods,
145 	      sc_errors;		/* number of retries so far */
146 	u_char sc_status[7];		/* copy of registers */
147 
148 	int sc_hwflags;
149 	int sc_swflags;
150 	u_int sc_fifolen;
151 
152 	u_int sc_r_hiwat,
153 	      sc_r_lowat;
154 	u_char *volatile sc_rbget,
155 	       *volatile sc_rbput;
156  	volatile u_int sc_rbavail;
157 	u_char *sc_rbuf,
158 	       *sc_ebuf;
159 
160  	u_char *sc_tba;			/* transmit buffer address */
161  	u_int sc_tbc,			/* transmit byte count */
162 	      sc_heldtbc;
163 
164 	volatile u_char sc_rx_flags,
165 #define	RX_TTY_BLOCKED		0x01
166 #define	RX_TTY_OVERFLOWED	0x02
167 #define	RX_IBUF_BLOCKED		0x04
168 #define	RX_IBUF_OVERFLOWED	0x08
169 #define	RX_ANY_BLOCK		0x0f
170 			sc_tx_busy,	/* working on an output chunk */
171 			sc_tx_done,	/* done with one output chunk */
172 			sc_tx_stopped,	/* H/W level stop (lost CTS) */
173 			sc_st_check,	/* got a status interrupt */
174 			sc_rx_ready;
175 
176 	volatile u_char sc_heldchange;
177 };
178 
179 /* controller driver configuration */
180 int scif_match(struct device *, void *, void *);
181 void scif_attach(struct device *, struct device *, void *);
182 
183 void	scif_break(struct scif_softc *, int);
184 void	scif_iflush(struct scif_softc *);
185 
186 void 	scifsoft(void *);
187 void scif_rxsoft(struct scif_softc *, struct tty *);
188 void scif_txsoft(struct scif_softc *, struct tty *);
189 void scif_stsoft(struct scif_softc *, struct tty *);
190 void scif_schedrx(struct scif_softc *);
191 void	scifdiag(void *);
192 
193 
194 #define	SCIFUNIT_MASK		0x7ffff
195 #define	SCIFDIALOUT_MASK	0x80000
196 
197 #define	SCIFUNIT(x)	(minor(x) & SCIFUNIT_MASK)
198 #define	SCIFDIALOUT(x)	(minor(x) & SCIFDIALOUT_MASK)
199 
200 /* Hardware flag masks */
201 #define	SCIF_HW_NOIEN	0x01
202 #define	SCIF_HW_FIFO	0x02
203 #define	SCIF_HW_FLOW	0x08
204 #define	SCIF_HW_DEV_OK	0x20
205 #define	SCIF_HW_CONSOLE	0x40
206 
207 /* Buffer size for character buffer */
208 #define	SCIF_RING_SIZE	2048
209 
210 /* Stop input when 3/4 of the ring is full; restart when only 1/4 is full. */
211 u_int scif_rbuf_hiwat = (SCIF_RING_SIZE * 1) / 4;
212 u_int scif_rbuf_lowat = (SCIF_RING_SIZE * 3) / 4;
213 
214 #define	CONMODE ((TTYDEF_CFLAG & ~(CSIZE | CSTOPB | PARENB)) | CS8) /* 8N1 */
215 int scifconscflag = CONMODE;
216 int scifisconsole = 0;
217 
218 #ifdef SCIFCN_SPEED
219 unsigned int scifcn_speed = SCIFCN_SPEED;
220 #else
221 unsigned int scifcn_speed = 9600;
222 #endif
223 
224 #define	divrnd(n, q)	(((n)*2/(q)+1)/2)	/* divide and round off */
225 
226 u_int scif_rbuf_size = SCIF_RING_SIZE;
227 
228 struct cfattach scif_ca = {
229 	sizeof(struct scif_softc), scif_match, scif_attach
230 };
231 
232 struct cfdriver scif_cd = {
233 	0, "scif", DV_DULL
234 };
235 
236 static int scif_attached;
237 
238 void InitializeScif(unsigned int);
239 
240 /*
241  * following functions are debugging prupose only
242  */
243 #define	CR      0x0D
244 #define	USART_ON (unsigned int)~0x08
245 
246 void scif_putc(unsigned char);
247 unsigned char scif_getc(void);
248 int ScifErrCheck(void);
249 
250 
251 /* XXX: uwe
252  * Prepare for bus_spacification.  The difference in access widths is
253  * still handled by the magic definitions in scifreg.h
254  */
255 #define scif_smr_read()		SHREG_SCSMR2
256 #define scif_smr_write(v)	(SHREG_SCSMR2 = (v))
257 
258 #define scif_brr_read()		SHREG_SCBRR2
259 #define scif_brr_write(v)	(SHREG_SCBRR2 = (v))
260 
261 #define scif_scr_read()		SHREG_SCSCR2
262 #define scif_scr_write(v)	(SHREG_SCSCR2 = (v))
263 
264 #define scif_ftdr_write(v)	(SHREG_SCFTDR2 = (v))
265 
266 #define scif_ssr_read()		SHREG_SCSSR2
267 #define scif_ssr_write(v)	(SHREG_SCSSR2 = (v))
268 
269 #define scif_frdr_read()	SHREG_SCFRDR2
270 
271 #define scif_fcr_read()		SHREG_SCFCR2
272 #define scif_fcr_write(v)	(SHREG_SCFCR2 = (v))
273 
274 #define scif_fdr_read()		SHREG_SCFDR2
275 
276 #ifdef SH4 /* additional registers in sh4 */
277 
278 #define scif_sptr_read()	SHREG_SCSPTR2
279 #define scif_sptr_write(v)	(SHREG_SCSPTR2 = (v))
280 
281 #define scif_lsr_read()		SHREG_SCLSR2
282 #define scif_lsr_write(v)	(SHREG_SCLSR2 = (v))
283 
284 #endif /* SH4 */
285 
286 
287 /*
288  * InitializeScif
289  * : unsigned int bps;
290  * : SCIF(Serial Communication Interface)
291  */
292 
293 void
294 InitializeScif(unsigned int bps)
295 {
296 	/* Initialize SCR */
297 	scif_scr_write(0x00);
298 
299 #if 0
300 	scif_fcr_write(SCFCR2_TFRST | SCFCR2_RFRST | SCFCR2_MCE);
301 #else
302 	scif_fcr_write(SCFCR2_TFRST | SCFCR2_RFRST);
303 #endif
304 	/* Serial Mode Register */
305 	scif_smr_write(0x00);	/* 8bit,NonParity,Even,1Stop */
306 
307 	/* Bit Rate Register */
308 	scif_brr_write(divrnd(sh_clock_get_pclock(), 32 * bps) - 1);
309 
310 	/*
311 	 * wait 2m Sec, because Send/Recv must begin 1 bit period after
312 	 * BRR is set.
313 	 */
314 	delay(2000);
315 
316 #if 0
317 	scif_fcr_write(FIFO_RCV_TRIGGER_14 | FIFO_XMT_TRIGGER_1 | SCFCR2_MCE);
318 #else
319 	scif_fcr_write(FIFO_RCV_TRIGGER_14 | FIFO_XMT_TRIGGER_1);
320 #endif
321 
322 	/* Send permission, Receive permission ON */
323 	scif_scr_write(SCSCR2_TE | SCSCR2_RE);
324 
325 	/* Serial Status Register */
326 	scif_ssr_write(scif_ssr_read() & SCSSR2_TDFE); /* Clear Status */
327 }
328 
329 
330 /*
331  * scif_putc
332  *  : unsigned char c;
333  */
334 
335 void
336 scif_putc(unsigned char c)
337 {
338 	/* wait for ready */
339 	while ((scif_fdr_read() & SCFDR2_TXCNT) == SCFDR2_TXF_FULL)
340 		continue;
341 
342 	/* write send data to send register */
343 	scif_ftdr_write(c);
344 
345 	/* clear ready flag */
346 	scif_ssr_write(scif_ssr_read() & ~(SCSSR2_TDFE | SCSSR2_TEND));
347 }
348 
349 /*
350  * : ScifErrCheck
351  *	0x80 = error
352  *	0x08 = frame error
353  *	0x04 = parity error
354  */
355 int
356 ScifErrCheck(void)
357 {
358 	return (scif_ssr_read() & (SCSSR2_ER | SCSSR2_FER | SCSSR2_PER));
359 }
360 
361 /*
362  * scif_getc
363  */
364 unsigned char
365 scif_getc(void)
366 {
367 	unsigned char c, err_c;
368 #ifdef SH4
369 	unsigned short err_c2 = 0; /* XXXGCC: -Wuninitialized */
370 #endif
371 
372 	for (;;) {
373 		/* wait for ready */
374 		while ((scif_fdr_read() & SCFDR2_RECVCNT) == 0)
375 			continue;
376 
377 		c = scif_frdr_read();
378 		err_c = scif_ssr_read();
379 		scif_ssr_write(scif_ssr_read()
380 			& ~(SCSSR2_ER | SCSSR2_BRK | SCSSR2_RDF | SCSSR2_DR));
381 #ifdef SH4
382 		if (CPU_IS_SH4) {
383 			err_c2 = scif_lsr_read();
384 			scif_lsr_write(scif_lsr_read() & ~SCLSR2_ORER);
385 		}
386 #endif
387 		if ((err_c & (SCSSR2_ER | SCSSR2_BRK | SCSSR2_FER
388 		    | SCSSR2_PER)) == 0) {
389 #ifdef SH4
390 			if (CPU_IS_SH4 && ((err_c2 & SCLSR2_ORER) == 0))
391 #endif
392 			return(c);
393 		}
394 	}
395 
396 }
397 
398 int
399 scif_match(struct device *parent, void *vcf, void *aux)
400 {
401 	if (scif_attached != 0)
402 		return 0;
403 
404 	return 1;
405 }
406 
407 void
408 scif_attach(struct device *parent, struct device *self, void *aux)
409 {
410 	struct scif_softc *sc = (struct scif_softc *)self;
411 	struct tty *tp;
412 
413 	scif_attached = 1;
414 
415 	sc->sc_hwflags = 0;	/* XXX */
416 	sc->sc_swflags = 0;	/* XXX */
417 	sc->sc_fifolen = 16;
418 
419 	if (scifisconsole) {
420 		/* InitializeScif(scifcn_speed); */
421 		SET(sc->sc_hwflags, SCIF_HW_CONSOLE);
422 		SET(sc->sc_swflags, TIOCFLAG_SOFTCAR);
423 		printf("\n%s: console\n", sc->sc_dev.dv_xname);
424 	} else {
425 		InitializeScif(9600);
426 		printf("\n");
427 	}
428 
429 	timeout_set(&sc->sc_diag_tmo, scifdiag, sc);
430 #ifdef SH4
431 	intc_intr_establish(SH4_INTEVT_SCIF_ERI, IST_LEVEL, IPL_TTY,
432 	    scifintr, sc, self->dv_xname);
433 	intc_intr_establish(SH4_INTEVT_SCIF_RXI, IST_LEVEL, IPL_TTY,
434 	    scifintr, sc, self->dv_xname);
435 	intc_intr_establish(SH4_INTEVT_SCIF_BRI, IST_LEVEL, IPL_TTY,
436 	    scifintr, sc, self->dv_xname);
437 	intc_intr_establish(SH4_INTEVT_SCIF_TXI, IST_LEVEL, IPL_TTY,
438 	    scifintr, sc, self->dv_xname);
439 #else
440 	intc_intr_establish(SH7709_INTEVT2_SCIF_ERI, IST_LEVEL, IPL_TTY,
441 	    scifintr, sc, self->dv_xname);
442 	intc_intr_establish(SH7709_INTEVT2_SCIF_RXI, IST_LEVEL, IPL_TTY,
443 	    scifintr, sc, self->dv_xname);
444 	intc_intr_establish(SH7709_INTEVT2_SCIF_BRI, IST_LEVEL, IPL_TTY,
445 	    scifintr, sc, self->dv_xname);
446 	intc_intr_establish(SH7709_INTEVT2_SCIF_TXI, IST_LEVEL, IPL_TTY,
447 	    scifintr, sc, self->dv_xname);
448 #endif
449 
450 	sc->sc_si = softintr_establish(IPL_SOFTSERIAL, scifsoft, sc);
451 	SET(sc->sc_hwflags, SCIF_HW_DEV_OK);
452 
453 	tp = ttymalloc(0);
454 	tp->t_oproc = scifstart;
455 	tp->t_param = scifparam;
456 	tp->t_hwiflow = NULL;
457 
458 	sc->sc_tty = tp;
459 	sc->sc_rbuf = malloc(scif_rbuf_size << 1, M_DEVBUF, M_NOWAIT);
460 	if (sc->sc_rbuf == NULL) {
461 		printf("%s: unable to allocate ring buffer\n",
462 		    sc->sc_dev.dv_xname);
463 		return;
464 	}
465 	sc->sc_ebuf = sc->sc_rbuf + (scif_rbuf_size << 1);
466 }
467 
468 /*
469  * Start or restart transmission.
470  */
471 void
472 scifstart(struct tty *tp)
473 {
474 	struct scif_softc *sc = scif_cd.cd_devs[SCIFUNIT(tp->t_dev)];
475 	int s;
476 
477 	s = spltty();
478 	if (ISSET(tp->t_state, TS_BUSY | TS_TIMEOUT | TS_TTSTOP))
479 		goto out;
480 	if (sc->sc_tx_stopped)
481 		goto out;
482 
483 	ttwakeupwr(tp);
484 	if (tp->t_outq.c_cc == 0)
485 		goto out;
486 
487 	/* Grab the first contiguous region of buffer space. */
488 	{
489 		u_char *tba;
490 		int tbc;
491 
492 		tba = tp->t_outq.c_cf;
493 		tbc = ndqb(&tp->t_outq, 0);
494 
495 
496 		sc->sc_tba = tba;
497 		sc->sc_tbc = tbc;
498 	}
499 
500 	SET(tp->t_state, TS_BUSY);
501 	sc->sc_tx_busy = 1;
502 
503 	/* Enable transmit completion interrupts if necessary. */
504 	scif_scr_write(scif_scr_read() | SCSCR2_TIE | SCSCR2_RIE);
505 
506 	/* Output the first chunk of the contiguous buffer. */
507 	{
508 		int n;
509 		int maxchars;
510 		int i;
511 
512 		n = sc->sc_tbc;
513 		maxchars = sc->sc_fifolen
514 			- ((scif_fdr_read() & SCFDR2_TXCNT) >> 8);
515 		if (n > maxchars)
516 			n = maxchars;
517 
518 		for (i = 0; i < n; i++) {
519 			scif_putc(*(sc->sc_tba));
520 			sc->sc_tba++;
521 		}
522 		sc->sc_tbc -= n;
523 	}
524 out:
525 	splx(s);
526 	return;
527 }
528 
529 /*
530  * Set SCIF tty parameters from termios.
531  * XXX - Should just copy the whole termios after
532  * making sure all the changes could be done.
533  */
534 int
535 scifparam(struct tty *tp, struct termios *t)
536 {
537 	struct scif_softc *sc = scif_cd.cd_devs[SCIFUNIT(tp->t_dev)];
538 	int ospeed = t->c_ospeed;
539 	int s;
540 
541 	/* Check requested parameters. */
542 	if (ospeed < 0)
543 		return (EINVAL);
544 	if (t->c_ispeed && t->c_ispeed != t->c_ospeed)
545 		return (EINVAL);
546 
547 	/*
548 	 * For the console, always force CLOCAL and !HUPCL, so that the port
549 	 * is always active.
550 	 */
551 	if (ISSET(sc->sc_swflags, TIOCFLAG_SOFTCAR) ||
552 	    ISSET(sc->sc_hwflags, SCIF_HW_CONSOLE)) {
553 		SET(t->c_cflag, CLOCAL);
554 		CLR(t->c_cflag, HUPCL);
555 	}
556 
557 	/*
558 	 * If there were no changes, don't do anything.  This avoids dropping
559 	 * input and improves performance when all we did was frob things like
560 	 * VMIN and VTIME.
561 	 */
562 	if (tp->t_ospeed == t->c_ospeed &&
563 	    tp->t_cflag == t->c_cflag)
564 		return (0);
565 
566 #if 0
567 /* XXX (msaitoh) */
568 	lcr = ISSET(sc->sc_lcr, LCR_SBREAK) | cflag2lcr(t->c_cflag);
569 #endif
570 
571 	s = spltty();
572 
573 	/*
574 	 * Set the flow control pins depending on the current flow control
575 	 * mode.
576 	 */
577 	if (ISSET(t->c_cflag, CRTSCTS)) {
578 		scif_fcr_write(scif_fcr_read() | SCFCR2_MCE);
579 	} else {
580 		scif_fcr_write(scif_fcr_read() & ~SCFCR2_MCE);
581 	}
582 
583 	scif_brr_write(divrnd(sh_clock_get_pclock(), 32 * ospeed) -1);
584 
585 	/*
586 	 * Set the FIFO threshold based on the receive speed.
587 	 *
588 	 *  * If it's a low speed, it's probably a mouse or some other
589 	 *    interactive device, so set the threshold low.
590 	 *  * If it's a high speed, trim the trigger level down to prevent
591 	 *    overflows.
592 	 *  * Otherwise set it a bit higher.
593 	 */
594 #if 0
595 /* XXX (msaitoh) */
596 	if (ISSET(sc->sc_hwflags, SCIF_HW_HAYESP))
597 		sc->sc_fifo = FIFO_DMA_MODE | FIFO_ENABLE | FIFO_TRIGGER_8;
598 	else if (ISSET(sc->sc_hwflags, SCIF_HW_FIFO))
599 		sc->sc_fifo = FIFO_ENABLE |
600 		    (t->c_ospeed <= 1200 ? FIFO_TRIGGER_1 :
601 		     t->c_ospeed <= 38400 ? FIFO_TRIGGER_8 : FIFO_TRIGGER_4);
602 	else
603 		sc->sc_fifo = 0;
604 #endif
605 
606 	/* And copy to tty. */
607 	tp->t_ispeed = 0;
608 	tp->t_ospeed = t->c_ospeed;
609 	tp->t_cflag = t->c_cflag;
610 
611 	if (!sc->sc_heldchange) {
612 		if (sc->sc_tx_busy) {
613 			sc->sc_heldtbc = sc->sc_tbc;
614 			sc->sc_tbc = 0;
615 			sc->sc_heldchange = 1;
616 		}
617 #if 0
618 /* XXX (msaitoh) */
619 		else
620 			scif_loadchannelregs(sc);
621 #endif
622 	}
623 
624 	if (!ISSET(t->c_cflag, CHWFLOW)) {
625 		/* Disable the high water mark. */
626 		sc->sc_r_hiwat = 0;
627 		sc->sc_r_lowat = 0;
628 		if (ISSET(sc->sc_rx_flags, RX_TTY_OVERFLOWED)) {
629 			CLR(sc->sc_rx_flags, RX_TTY_OVERFLOWED);
630 			scif_schedrx(sc);
631 		}
632 	} else {
633 		sc->sc_r_hiwat = scif_rbuf_hiwat;
634 		sc->sc_r_lowat = scif_rbuf_lowat;
635 	}
636 
637 	splx(s);
638 
639 #ifdef SCIF_DEBUG
640 	if (scif_debug)
641 		scifstatus(sc, "scifparam ");
642 #endif
643 
644 	if (!ISSET(t->c_cflag, CHWFLOW)) {
645 		if (sc->sc_tx_stopped) {
646 			sc->sc_tx_stopped = 0;
647 			scifstart(tp);
648 		}
649 	}
650 
651 	return (0);
652 }
653 
654 void
655 scif_iflush(struct scif_softc *sc)
656 {
657 	int i;
658 	unsigned char c;
659 
660 	i = scif_fdr_read() & SCFDR2_RECVCNT;
661 
662 	while (i > 0) {
663 		c = scif_frdr_read();
664 		scif_ssr_write(scif_ssr_read() & ~(SCSSR2_RDF | SCSSR2_DR));
665 		i--;
666 	}
667 }
668 
669 int
670 scifopen(dev_t dev, int flag, int mode, struct proc *p)
671 {
672 	int unit = SCIFUNIT(dev);
673 	struct scif_softc *sc;
674 	struct tty *tp;
675 	int s;
676 	int error;
677 
678 	if (unit >= scif_cd.cd_ndevs)
679 		return (ENXIO);
680 	sc = scif_cd.cd_devs[unit];
681 	if (sc == 0 || !ISSET(sc->sc_hwflags, SCIF_HW_DEV_OK) ||
682 	    sc->sc_rbuf == NULL)
683 		return (ENXIO);
684 
685 	tp = sc->sc_tty;
686 
687 	if (ISSET(tp->t_state, TS_ISOPEN) &&
688 	    ISSET(tp->t_state, TS_XCLUDE) &&
689 	    suser(p) != 0)
690 		return (EBUSY);
691 
692 	s = spltty();
693 
694 	/*
695 	 * Do the following iff this is a first open.
696 	 */
697 	if (!ISSET(tp->t_state, TS_ISOPEN)) {
698 		struct termios t;
699 
700 		tp->t_dev = dev;
701 
702 
703 		/* Turn on interrupts. */
704 		scif_scr_write(scif_scr_read() | SCSCR2_TIE | SCSCR2_RIE);
705 
706 		/*
707 		 * Initialize the termios status to the defaults.  Add in the
708 		 * sticky bits from TIOCSFLAGS.
709 		 */
710 		t.c_ispeed = 0;
711 		if (ISSET(sc->sc_hwflags, SCIF_HW_CONSOLE)) {
712 			t.c_ospeed = scifcn_speed;	/* XXX (msaitoh) */
713 			t.c_cflag = scifconscflag;
714 		} else {
715 			t.c_ospeed = TTYDEF_SPEED;
716 			t.c_cflag = TTYDEF_CFLAG;
717 		}
718 		if (ISSET(sc->sc_swflags, TIOCFLAG_CLOCAL))
719 			SET(t.c_cflag, CLOCAL);
720 		if (ISSET(sc->sc_swflags, TIOCFLAG_CRTSCTS))
721 			SET(t.c_cflag, CRTSCTS);
722 		if (ISSET(sc->sc_swflags, TIOCFLAG_MDMBUF))
723 			SET(t.c_cflag, MDMBUF);
724 		/* Make sure scifparam() will do something. */
725 		tp->t_ospeed = 0;
726 		(void) scifparam(tp, &t);
727 
728 		/*
729 		 * XXX landisk has no hardware flow control!
730 		 * When porting to another platform, fix this somehow
731 		 */
732 		SET(tp->t_state, TS_CARR_ON);
733 
734 		tp->t_iflag = TTYDEF_IFLAG;
735 		tp->t_oflag = TTYDEF_OFLAG;
736 		tp->t_lflag = TTYDEF_LFLAG;
737 		ttychars(tp);
738 		ttsetwater(tp);
739 
740 		/* Clear the input ring, and unblock. */
741 		sc->sc_rbput = sc->sc_rbget = sc->sc_rbuf;
742 		sc->sc_rbavail = scif_rbuf_size;
743 		scif_iflush(sc);
744 		CLR(sc->sc_rx_flags, RX_ANY_BLOCK);
745 #if 0
746 /* XXX (msaitoh) */
747 		scif_hwiflow(sc);
748 #endif
749 
750 #ifdef SCIF_DEBUG
751 		if (scif_debug)
752 			scifstatus(sc, "scifopen  ");
753 #endif
754 
755 	}
756 
757 	splx(s);
758 
759 	error = ttyopen(dev, tp, p);
760 	if (error)
761 		goto bad;
762 
763 	error = (*linesw[tp->t_line].l_open)(dev, tp, p);
764 	if (error)
765 		goto bad;
766 
767 	return (0);
768 
769 bad:
770 
771 	return (error);
772 }
773 
774 int
775 scifclose(dev_t dev, int flag, int mode, struct proc *p)
776 {
777 	struct scif_softc *sc = scif_cd.cd_devs[SCIFUNIT(dev)];
778 	struct tty *tp = sc->sc_tty;
779 
780 	/* XXX This is for cons.c. */
781 	if (!ISSET(tp->t_state, TS_ISOPEN))
782 		return (0);
783 
784 	(*linesw[tp->t_line].l_close)(tp, flag, p);
785 	ttyclose(tp);
786 
787 	return (0);
788 }
789 
790 int
791 scifread(dev_t dev, struct uio *uio, int flag)
792 {
793 	struct scif_softc *sc = scif_cd.cd_devs[SCIFUNIT(dev)];
794 	struct tty *tp = sc->sc_tty;
795 
796 	return ((*linesw[tp->t_line].l_read)(tp, uio, flag));
797 }
798 
799 int
800 scifwrite(dev_t dev, struct uio *uio, int flag)
801 {
802 	struct scif_softc *sc = scif_cd.cd_devs[SCIFUNIT(dev)];
803 	struct tty *tp = sc->sc_tty;
804 
805 	return ((*linesw[tp->t_line].l_write)(tp, uio, flag));
806 }
807 
808 #if 0
809 int
810 scifpoll(dev_t dev, int events, struct proc *p)
811 {
812 	struct scif_softc *sc = scif_cd.cd_devs[SCIFUNIT(dev)];
813 	struct tty *tp = sc->sc_tty;
814 
815 	return ((*linesw[tp->t_line].l_poll)(tp, events, p));
816 }
817 #endif
818 
819 struct tty *
820 sciftty(dev_t dev)
821 {
822 	struct scif_softc *sc = scif_cd.cd_devs[SCIFUNIT(dev)];
823 	struct tty *tp = sc->sc_tty;
824 
825 	return (tp);
826 }
827 
828 int
829 scifioctl(dev_t dev, u_long cmd, caddr_t data, int flag, struct proc *p)
830 {
831 	struct scif_softc *sc = scif_cd.cd_devs[SCIFUNIT(dev)];
832 	struct tty *tp = sc->sc_tty;
833 	int error;
834 	int s;
835 
836 	error = (*linesw[tp->t_line].l_ioctl)(tp, cmd, data, flag, p);
837 	if (error != -1)
838 		return (error);
839 
840 	error = ttioctl(tp, cmd, data, flag, p);
841 	if (error != -1)
842 		return (error);
843 
844 	error = 0;
845 
846 	s = spltty();
847 
848 	switch (cmd) {
849 	case TIOCSBRK:
850 		scif_break(sc, 1);
851 		break;
852 
853 	case TIOCCBRK:
854 		scif_break(sc, 0);
855 		break;
856 
857 	case TIOCGFLAGS:
858 		*(int *)data = sc->sc_swflags;
859 		break;
860 
861 	case TIOCSFLAGS:
862 		error = suser(p);
863 		if (error)
864 			break;
865 		sc->sc_swflags = *(int *)data;
866 		break;
867 
868 	default:
869 		error = -1;
870 		break;
871 	}
872 
873 	splx(s);
874 
875 	return (error);
876 }
877 
878 void
879 scif_schedrx(struct scif_softc *sc)
880 {
881 	sc->sc_rx_ready = 1;
882 
883 	/* Wake up the poller. */
884 	softintr_schedule(sc->sc_si);
885 }
886 
887 void
888 scif_break(struct scif_softc *sc, int onoff)
889 {
890 	if (onoff)
891 		scif_ssr_write(scif_ssr_read() & ~SCSSR2_TDFE);
892 	else
893 		scif_ssr_write(scif_ssr_read() | SCSSR2_TDFE);
894 
895 #if 0	/* XXX */
896 	if (!sc->sc_heldchange) {
897 		if (sc->sc_tx_busy) {
898 			sc->sc_heldtbc = sc->sc_tbc;
899 			sc->sc_tbc = 0;
900 			sc->sc_heldchange = 1;
901 		} else
902 			scif_loadchannelregs(sc);
903 	}
904 #endif
905 }
906 
907 /*
908  * Stop output, e.g., for ^S or output flush.
909  */
910 int
911 scifstop(struct tty *tp, int flag)
912 {
913 	struct scif_softc *sc = scif_cd.cd_devs[SCIFUNIT(tp->t_dev)];
914 	int s;
915 
916 	s = spltty();
917 	if (ISSET(tp->t_state, TS_BUSY)) {
918 		/* Stop transmitting at the next chunk. */
919 		sc->sc_tbc = 0;
920 		sc->sc_heldtbc = 0;
921 		if (!ISSET(tp->t_state, TS_TTSTOP))
922 			SET(tp->t_state, TS_FLUSH);
923 	}
924 	splx(s);
925 	return (0);
926 }
927 
928 void
929 scif_intr_init(void)
930 {
931 	/* XXX */
932 }
933 
934 void
935 scifdiag(void *arg)
936 {
937 	struct scif_softc *sc = arg;
938 	int overflows, floods;
939 	int s;
940 
941 	s = spltty();
942 	overflows = sc->sc_overflows;
943 	sc->sc_overflows = 0;
944 	floods = sc->sc_floods;
945 	sc->sc_floods = 0;
946 	sc->sc_errors = 0;
947 	splx(s);
948 
949 	log(LOG_WARNING, "%s: %d silo overflow%s, %d ibuf flood%s\n",
950 	    sc->sc_dev.dv_xname,
951 	    overflows, overflows == 1 ? "" : "s",
952 	    floods, floods == 1 ? "" : "s");
953 }
954 
955 void
956 scif_rxsoft(struct scif_softc *sc, struct tty *tp)
957 {
958 	int (*rint)(int, struct tty *) = *linesw[tp->t_line].l_rint;
959 	u_char *get, *end;
960 	u_int cc, scc;
961 	u_char ssr2;
962 	int code;
963 	int s;
964 
965 	end = sc->sc_ebuf;
966 	get = sc->sc_rbget;
967 	scc = cc = scif_rbuf_size - sc->sc_rbavail;
968 
969 	if (cc == scif_rbuf_size) {
970 		sc->sc_floods++;
971 		if (sc->sc_errors++ == 0)
972 			timeout_add_sec(&sc->sc_diag_tmo, 60);
973 	}
974 
975 	while (cc) {
976 		code = get[0];
977 		ssr2 = get[1];
978 		if (ISSET(ssr2, SCSSR2_BRK | SCSSR2_FER | SCSSR2_PER)) {
979 			if (ISSET(ssr2, SCSSR2_BRK | SCSSR2_FER))
980 				SET(code, TTY_FE);
981 			if (ISSET(ssr2, SCSSR2_PER))
982 				SET(code, TTY_PE);
983 		}
984 		if ((*rint)(code, tp) == -1) {
985 			/*
986 			 * The line discipline's buffer is out of space.
987 			 */
988 			if (!ISSET(sc->sc_rx_flags, RX_TTY_BLOCKED)) {
989 				/*
990 				 * We're either not using flow control, or the
991 				 * line discipline didn't tell us to block for
992 				 * some reason.  Either way, we have no way to
993 				 * know when there's more space available, so
994 				 * just drop the rest of the data.
995 				 */
996 				get += cc << 1;
997 				if (get >= end)
998 					get -= scif_rbuf_size << 1;
999 				cc = 0;
1000 			} else {
1001 				/*
1002 				 * Don't schedule any more receive processing
1003 				 * until the line discipline tells us there's
1004 				 * space available (through scifhwiflow()).
1005 				 * Leave the rest of the data in the input
1006 				 * buffer.
1007 				 */
1008 				SET(sc->sc_rx_flags, RX_TTY_OVERFLOWED);
1009 			}
1010 			break;
1011 		}
1012 		get += 2;
1013 		if (get >= end)
1014 			get = sc->sc_rbuf;
1015 		cc--;
1016 	}
1017 
1018 	if (cc != scc) {
1019 		sc->sc_rbget = get;
1020 		s = spltty();
1021 		cc = sc->sc_rbavail += scc - cc;
1022 		/* Buffers should be ok again, release possible block. */
1023 		if (cc >= sc->sc_r_lowat) {
1024 			if (ISSET(sc->sc_rx_flags, RX_IBUF_OVERFLOWED)) {
1025 				CLR(sc->sc_rx_flags, RX_IBUF_OVERFLOWED);
1026 				scif_scr_write(scif_scr_read() | SCSCR2_RIE);
1027 			}
1028 #if 0
1029 			if (ISSET(sc->sc_rx_flags, RX_IBUF_BLOCKED)) {
1030 				CLR(sc->sc_rx_flags, RX_IBUF_BLOCKED);
1031 				scif_hwiflow(sc);
1032 			}
1033 #endif
1034 		}
1035 		splx(s);
1036 	}
1037 }
1038 
1039 void
1040 scif_txsoft(struct scif_softc *sc, struct tty *tp)
1041 {
1042 	CLR(tp->t_state, TS_BUSY);
1043 	if (ISSET(tp->t_state, TS_FLUSH))
1044 		CLR(tp->t_state, TS_FLUSH);
1045 	else
1046 		ndflush(&tp->t_outq, (int)(sc->sc_tba - tp->t_outq.c_cf));
1047 	(*linesw[tp->t_line].l_start)(tp);
1048 }
1049 
1050 void
1051 scif_stsoft(struct scif_softc *sc, struct tty *tp)
1052 {
1053 #if 0
1054 /* XXX (msaitoh) */
1055 	u_char msr, delta;
1056 	int s;
1057 
1058 	s = spltty();
1059 	msr = sc->sc_msr;
1060 	delta = sc->sc_msr_delta;
1061 	sc->sc_msr_delta = 0;
1062 	splx(s);
1063 
1064 	if (ISSET(delta, sc->sc_msr_dcd)) {
1065 		/*
1066 		 * Inform the tty layer that carrier detect changed.
1067 		 */
1068 		(void) (*linesw[tp->t_line].l_modem)(tp, ISSET(msr, MSR_DCD));
1069 	}
1070 
1071 	if (ISSET(delta, sc->sc_msr_cts)) {
1072 		/* Block or unblock output according to flow control. */
1073 		if (ISSET(msr, sc->sc_msr_cts)) {
1074 			sc->sc_tx_stopped = 0;
1075 			(*linesw[tp->t_line].l_start)(tp);
1076 		} else {
1077 			sc->sc_tx_stopped = 1;
1078 		}
1079 	}
1080 
1081 #ifdef SCIF_DEBUG
1082 	if (scif_debug)
1083 		scifstatus(sc, "scif_stsoft");
1084 #endif
1085 #endif
1086 }
1087 
1088 void
1089 scifsoft(void *arg)
1090 {
1091 	struct scif_softc *sc = arg;
1092 	struct tty *tp;
1093 
1094 	tp = sc->sc_tty;
1095 
1096 	if (sc->sc_rx_ready) {
1097 		sc->sc_rx_ready = 0;
1098 		scif_rxsoft(sc, tp);
1099 	}
1100 
1101 #if 0
1102 	if (sc->sc_st_check) {
1103 		sc->sc_st_check = 0;
1104 		scif_stsoft(sc, tp);
1105 	}
1106 #endif
1107 
1108 	if (sc->sc_tx_done) {
1109 		sc->sc_tx_done = 0;
1110 		scif_txsoft(sc, tp);
1111 	}
1112 }
1113 
1114 int
1115 scifintr(void *arg)
1116 {
1117 	struct scif_softc *sc = arg;
1118 	u_char *put, *end;
1119 	u_int cc;
1120 	u_short ssr2;
1121 	int count;
1122 
1123 	end = sc->sc_ebuf;
1124 	put = sc->sc_rbput;
1125 	cc = sc->sc_rbavail;
1126 
1127 	do {
1128 		ssr2 = scif_ssr_read();
1129 		if (ISSET(ssr2, SCSSR2_BRK)) {
1130 			scif_ssr_write(scif_ssr_read()
1131 				& ~(SCSSR2_ER | SCSSR2_BRK | SCSSR2_DR));
1132 #ifdef DDB
1133 			if (ISSET(sc->sc_hwflags, SCIF_HW_CONSOLE) &&
1134 			    db_console != 0) {
1135 				db_enter();
1136 			}
1137 #endif /* DDB */
1138 		}
1139 		count = scif_fdr_read() & SCFDR2_RECVCNT;
1140 		if (count != 0) {
1141 			for (;;) {
1142 				u_char c = scif_frdr_read();
1143 				u_char err = (u_char)(scif_ssr_read() & 0x00ff);
1144 
1145 				scif_ssr_write(scif_ssr_read()
1146 				    & ~(SCSSR2_ER | SCSSR2_RDF | SCSSR2_DR));
1147 #ifdef SH4
1148 				if (CPU_IS_SH4)
1149 					scif_lsr_write(scif_lsr_read()
1150 						       & ~SCLSR2_ORER);
1151 #endif
1152 				if ((cc > 0) && (count > 0)) {
1153 					put[0] = c;
1154 					put[1] = err;
1155 					put += 2;
1156 					if (put >= end)
1157 						put = sc->sc_rbuf;
1158 					cc--;
1159 					count--;
1160 				} else
1161 					break;
1162 			}
1163 
1164 			/*
1165 			 * Current string of incoming characters ended because
1166 			 * no more data was available or we ran out of space.
1167 			 * Schedule a receive event if any data was received.
1168 			 * If we're out of space, turn off receive interrupts.
1169 			 */
1170 			sc->sc_rbput = put;
1171 			sc->sc_rbavail = cc;
1172 			if (!ISSET(sc->sc_rx_flags, RX_TTY_OVERFLOWED))
1173 				sc->sc_rx_ready = 1;
1174 
1175 			/*
1176 			 * See if we are in danger of overflowing a buffer. If
1177 			 * so, use hardware flow control to ease the pressure.
1178 			 */
1179 			if (!ISSET(sc->sc_rx_flags, RX_IBUF_BLOCKED) &&
1180 			    cc < sc->sc_r_hiwat) {
1181 				SET(sc->sc_rx_flags, RX_IBUF_BLOCKED);
1182 #if 0
1183 				scif_hwiflow(sc);
1184 #endif
1185 			}
1186 
1187 			/*
1188 			 * If we're out of space, disable receive interrupts
1189 			 * until the queue has drained a bit.
1190 			 */
1191 			if (!cc) {
1192 				SET(sc->sc_rx_flags, RX_IBUF_OVERFLOWED);
1193 				scif_scr_write(scif_scr_read() & ~SCSCR2_RIE);
1194 			}
1195 		} else {
1196 			if (scif_ssr_read() & (SCSSR2_RDF | SCSSR2_DR)) {
1197 				scif_scr_write(scif_scr_read()
1198 					       & ~(SCSCR2_TIE | SCSCR2_RIE));
1199 				delay(10);
1200 				scif_scr_write(scif_scr_read()
1201 					       | SCSCR2_TIE | SCSCR2_RIE);
1202 				continue;
1203 			}
1204 		}
1205 	} while (scif_ssr_read() & (SCSSR2_RDF | SCSSR2_DR));
1206 
1207 #if 0
1208 	msr = bus_space_read_1(iot, ioh, scif_msr);
1209 	delta = msr ^ sc->sc_msr;
1210 	sc->sc_msr = msr;
1211 	if (ISSET(delta, sc->sc_msr_mask)) {
1212 		SET(sc->sc_msr_delta, delta);
1213 
1214 		/*
1215 		 * Pulse-per-second clock signal on edge of DCD?
1216 		 */
1217 		if (ISSET(delta, sc->sc_ppsmask)) {
1218 			struct timeval tv;
1219 			if (ISSET(msr, sc->sc_ppsmask) ==
1220 			    sc->sc_ppsassert) {
1221 				/* XXX nanotime() */
1222 				microtime(&tv);
1223 				TIMEVAL_TO_TIMESPEC(&tv,
1224 						    &sc->ppsinfo.assert_timestamp);
1225 				if (sc->ppsparam.mode & PPS_OFFSETASSERT) {
1226 					timespecadd(&sc->ppsinfo.assert_timestamp,
1227 						    &sc->ppsparam.assert_offset,
1228 						    &sc->ppsinfo.assert_timestamp);
1229 					TIMESPEC_TO_TIMEVAL(&tv, &sc->ppsinfo.assert_timestamp);
1230 				}
1231 
1232 #ifdef PPS_SYNC
1233 				if (sc->ppsparam.mode & PPS_HARDPPSONASSERT)
1234 					hardpps(&tv, tv.tv_usec);
1235 #endif
1236 				sc->ppsinfo.assert_sequence++;
1237 				sc->ppsinfo.current_mode =
1238 					sc->ppsparam.mode;
1239 
1240 			} else if (ISSET(msr, sc->sc_ppsmask) ==
1241 				   sc->sc_ppsclear) {
1242 				/* XXX nanotime() */
1243 				microtime(&tv);
1244 				TIMEVAL_TO_TIMESPEC(&tv,
1245 						    &sc->ppsinfo.clear_timestamp);
1246 				if (sc->ppsparam.mode & PPS_OFFSETCLEAR) {
1247 					timespecadd(&sc->ppsinfo.clear_timestamp,
1248 						    &sc->ppsparam.clear_offset,
1249 						    &sc->ppsinfo.clear_timestamp);
1250 					TIMESPEC_TO_TIMEVAL(&tv, &sc->ppsinfo.clear_timestamp);
1251 				}
1252 
1253 #ifdef PPS_SYNC
1254 				if (sc->ppsparam.mode & PPS_HARDPPSONCLEAR)
1255 					hardpps(&tv, tv.tv_usec);
1256 #endif
1257 				sc->ppsinfo.clear_sequence++;
1258 				sc->ppsinfo.current_mode =
1259 					sc->ppsparam.mode;
1260 			}
1261 		}
1262 
1263 		/*
1264 		 * Stop output immediately if we lose the output
1265 		 * flow control signal or carrier detect.
1266 		 */
1267 		if (ISSET(~msr, sc->sc_msr_mask)) {
1268 			sc->sc_tbc = 0;
1269 			sc->sc_heldtbc = 0;
1270 #ifdef SCIF_DEBUG
1271 			if (scif_debug)
1272 				scifstatus(sc, "scifintr  ");
1273 #endif
1274 		}
1275 
1276 		sc->sc_st_check = 1;
1277 	}
1278 #endif
1279 
1280 	/*
1281 	 * Done handling any receive interrupts. See if data can be
1282 	 * transmitted as well. Schedule tx done event if no data left
1283 	 * and tty was marked busy.
1284 	 */
1285 	if (((scif_fdr_read() & SCFDR2_TXCNT) >> 8) != 16) { /* XXX (msaitoh) */
1286 		/*
1287 		 * If we've delayed a parameter change, do it now, and restart
1288 		 * output.
1289 		 */
1290 		if (sc->sc_heldchange) {
1291 			sc->sc_heldchange = 0;
1292 			sc->sc_tbc = sc->sc_heldtbc;
1293 			sc->sc_heldtbc = 0;
1294 		}
1295 
1296 		/* Output the next chunk of the contiguous buffer, if any. */
1297 		if (sc->sc_tbc > 0) {
1298 			int n;
1299 			int maxchars;
1300 			int i;
1301 
1302 			n = sc->sc_tbc;
1303 			maxchars = sc->sc_fifolen -
1304 				((scif_fdr_read() & SCFDR2_TXCNT) >> 8);
1305 			if (n > maxchars)
1306 				n = maxchars;
1307 
1308 			for (i = 0; i < n; i++) {
1309 				scif_putc(*(sc->sc_tba));
1310 				sc->sc_tba++;
1311 			}
1312 			sc->sc_tbc -= n;
1313 		} else {
1314 			/* Disable transmit completion interrupts if necessary. */
1315 #if 0
1316 			if (ISSET(sc->sc_ier, IER_ETXRDY))
1317 #endif
1318 				scif_scr_write(scif_scr_read() & ~SCSCR2_TIE);
1319 
1320 			if (sc->sc_tx_busy) {
1321 				sc->sc_tx_busy = 0;
1322 				sc->sc_tx_done = 1;
1323 			}
1324 		}
1325 	}
1326 
1327 	/* Wake up the poller. */
1328 	softintr_schedule(sc->sc_si);
1329 
1330 	return (1);
1331 }
1332 
1333 void
1334 scifcnprobe(struct consdev *cp)
1335 {
1336 	int maj;
1337 
1338 	/* locate the major number */
1339 	for (maj = 0; maj < nchrdev; maj++)
1340 		if (cdevsw[maj].d_open == scifopen)
1341 			break;
1342 
1343 	cp->cn_dev = makedev(maj, 0);
1344 #ifdef SCIFCONSOLE
1345 	cp->cn_pri = CN_HIGHPRI;
1346 #else
1347 	cp->cn_pri = CN_LOWPRI;
1348 #endif
1349 }
1350 
1351 void
1352 scifcninit(struct consdev *cp)
1353 {
1354 	InitializeScif(scifcn_speed);
1355 	scifisconsole = 1;
1356 }
1357 
1358 int
1359 scifcngetc(dev_t dev)
1360 {
1361 	int c;
1362 	int s;
1363 
1364 	s = spltty();
1365 	c = scif_getc();
1366 	splx(s);
1367 
1368 	return (c);
1369 }
1370 
1371 void
1372 scifcnputc(dev_t dev, int c)
1373 {
1374 	int s;
1375 
1376 	s = spltty();
1377 	scif_putc((u_char)c);
1378 	splx(s);
1379 }
1380