xref: /openbsd-src/sys/dev/ic/com.c (revision 99fd087599a8791921855f21bd7e36130f39aadc)
1 /*	$OpenBSD: com.c,v 1.171 2020/02/05 10:21:17 mpi Exp $	*/
2 /*	$NetBSD: com.c,v 1.82.4.1 1996/06/02 09:08:00 mrg Exp $	*/
3 
4 /*
5  * Copyright (c) 1997 - 1999, Jason Downs.  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  *
16  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR(S) ``AS IS'' AND ANY EXPRESS
17  * OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
18  * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
19  * DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR(S) BE LIABLE FOR ANY DIRECT,
20  * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
21  * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
22  * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
23  * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
24  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26  * SUCH DAMAGE.
27  */
28 /*-
29  * Copyright (c) 1993, 1994, 1995, 1996
30  *	Charles M. Hannum.  All rights reserved.
31  * Copyright (c) 1991 The Regents of the University of California.
32  * All rights reserved.
33  *
34  * Redistribution and use in source and binary forms, with or without
35  * modification, are permitted provided that the following conditions
36  * are met:
37  * 1. Redistributions of source code must retain the above copyright
38  *    notice, this list of conditions and the following disclaimer.
39  * 2. Redistributions in binary form must reproduce the above copyright
40  *    notice, this list of conditions and the following disclaimer in the
41  *    documentation and/or other materials provided with the distribution.
42  * 3. Neither the name of the University nor the names of its contributors
43  *    may be used to endorse or promote products derived from this software
44  *    without specific prior written permission.
45  *
46  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
47  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
48  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
49  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
50  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
51  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
52  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
53  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
54  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
55  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
56  * SUCH DAMAGE.
57  *
58  *	@(#)com.c	7.5 (Berkeley) 5/16/91
59  */
60 
61 /*
62  * COM driver, based on HP dca driver
63  * uses National Semiconductor NS16450/NS16550AF UART
64  */
65 #include <sys/param.h>
66 #include <sys/systm.h>
67 #include <sys/ioctl.h>
68 #include <sys/selinfo.h>
69 #include <sys/tty.h>
70 #include <sys/conf.h>
71 #include <sys/fcntl.h>
72 #include <sys/uio.h>
73 #include <sys/kernel.h>
74 #include <sys/syslog.h>
75 #include <sys/device.h>
76 #include <sys/vnode.h>
77 #ifdef DDB
78 #include <ddb/db_var.h>
79 #endif
80 
81 #include <machine/bus.h>
82 #include <machine/intr.h>
83 
84 #define	COM_CONSOLE
85 #include <dev/cons.h>
86 
87 #include <dev/ic/comreg.h>
88 #include <dev/ic/comvar.h>
89 #include <dev/ic/ns16550reg.h>
90 #define	com_lcr	com_cfcr
91 
92 cdev_decl(com);
93 
94 static u_char tiocm_xxx2mcr(int);
95 
96 void	compwroff(struct com_softc *);
97 void	cominit(bus_space_tag_t, bus_space_handle_t, int, int);
98 int	com_is_console(bus_space_tag_t, bus_addr_t);
99 
100 struct cfdriver com_cd = {
101 	NULL, "com", DV_TTY
102 };
103 
104 int	comdefaultrate = TTYDEF_SPEED;
105 #ifdef COM_CONSOLE
106 int	comconsfreq;
107 int	comconsrate = TTYDEF_SPEED;
108 bus_addr_t comconsaddr = 0;
109 int	comconsattached;
110 bus_space_tag_t comconsiot;
111 bus_space_handle_t comconsioh;
112 int	comconsunit;
113 tcflag_t comconscflag = TTYDEF_CFLAG;
114 #endif
115 
116 int	commajor;
117 
118 #define	DEVUNIT(x)	(minor(x) & 0x7f)
119 #define	DEVCUA(x)	(minor(x) & 0x80)
120 
121 int
122 comspeed(long freq, long speed)
123 {
124 #define	divrnd(n, q)	(((n)*2/(q)+1)/2)	/* divide and round off */
125 
126 	int x, err;
127 
128 	if (speed == 0)
129 		return 0;
130 	if (speed < 0)
131 		return -1;
132 	x = divrnd((freq / 16), speed);
133 	if (x <= 0)
134 		return -1;
135 	err = divrnd((quad_t)freq * 1000 / 16, speed * x) - 1000;
136 	if (err < 0)
137 		err = -err;
138 	if (err > COM_TOLERANCE)
139 		return -1;
140 	return x;
141 
142 #undef	divrnd
143 }
144 
145 #ifdef COM_CONSOLE
146 int
147 comprobe1(bus_space_tag_t iot, bus_space_handle_t ioh)
148 {
149 	int i, k;
150 
151 	/* force access to id reg */
152 	bus_space_write_1(iot, ioh, com_lcr, 0);
153 	bus_space_write_1(iot, ioh, com_iir, 0);
154 	for (i = 0; i < 32; i++) {
155 		k = bus_space_read_1(iot, ioh, com_iir);
156 		if (k & 0x38) {
157 			bus_space_read_1(iot, ioh, com_data); /* cleanup */
158 		} else
159 			break;
160 	}
161 	if (i >= 32)
162 		return 0;
163 
164 	return 1;
165 }
166 #endif
167 
168 int
169 com_detach(struct device *self, int flags)
170 {
171 	struct com_softc *sc = (struct com_softc *)self;
172 	int maj, mn;
173 
174 	sc->sc_swflags |= COM_SW_DEAD;
175 
176 	/* Locate the major number. */
177 	for (maj = 0; maj < nchrdev; maj++)
178 		if (cdevsw[maj].d_open == comopen)
179 			break;
180 
181 	/* Nuke the vnodes for any open instances. */
182 	mn = self->dv_unit;
183 	vdevgone(maj, mn, mn, VCHR);
184 
185 	/* XXX a symbolic constant for the cua bit would be nicer. */
186 	mn |= 0x80;
187 	vdevgone(maj, mn, mn, VCHR);
188 
189 	timeout_del(&sc->sc_dtr_tmo);
190 	timeout_del(&sc->sc_diag_tmo);
191 	softintr_disestablish(sc->sc_si);
192 
193 	/* Detach and free the tty. */
194 	if (sc->sc_tty) {
195 		ttyfree(sc->sc_tty);
196 	}
197 
198 	return (0);
199 }
200 
201 int
202 com_activate(struct device *self, int act)
203 {
204 	struct com_softc *sc = (struct com_softc *)self;
205 	int s, rv = 0;
206 
207 	switch (act) {
208 	case DVACT_SUSPEND:
209 		if (timeout_del(&sc->sc_dtr_tmo)) {
210 			/* Make sure DTR gets raised upon resume. */
211 			SET(sc->sc_mcr, MCR_DTR | MCR_RTS);
212 		}
213 		timeout_del(&sc->sc_diag_tmo);
214 		break;
215 	case DVACT_RESUME:
216 		com_resume(sc);
217 		break;
218 	case DVACT_DEACTIVATE:
219 		if (sc->sc_hwflags & COM_HW_CONSOLE) {
220 			rv = EBUSY;
221 			break;
222 		}
223 
224 		s = spltty();
225 		if (sc->disable != NULL && sc->enabled != 0) {
226 			(*sc->disable)(sc);
227 			sc->enabled = 0;
228 		}
229 		splx(s);
230 		break;
231 	}
232 	return (rv);
233 }
234 
235 int
236 comopen(dev_t dev, int flag, int mode, struct proc *p)
237 {
238 	int unit = DEVUNIT(dev);
239 	struct com_softc *sc;
240 	struct tty *tp;
241 	int s;
242 	int error = 0;
243 
244 	if (unit >= com_cd.cd_ndevs)
245 		return ENXIO;
246 	sc = com_cd.cd_devs[unit];
247 	if (!sc)
248 		return ENXIO;
249 
250 	s = spltty();
251 	if (!sc->sc_tty) {
252 		tp = sc->sc_tty = ttymalloc(1000000);
253 	} else
254 		tp = sc->sc_tty;
255 	splx(s);
256 
257 	tp->t_oproc = comstart;
258 	tp->t_param = comparam;
259 	tp->t_dev = dev;
260 	if (!ISSET(tp->t_state, TS_ISOPEN)) {
261 		SET(tp->t_state, TS_WOPEN);
262 		ttychars(tp);
263 		tp->t_iflag = TTYDEF_IFLAG;
264 		tp->t_oflag = TTYDEF_OFLAG;
265 #ifdef COM_CONSOLE
266 		if (ISSET(sc->sc_hwflags, COM_HW_CONSOLE)) {
267 			tp->t_cflag = comconscflag;
268 			tp->t_ispeed = tp->t_ospeed = comconsrate;
269 		} else
270 #endif
271 		{
272 			tp->t_cflag = TTYDEF_CFLAG;
273 			tp->t_ispeed = tp->t_ospeed = comdefaultrate;
274 		}
275 		if (ISSET(sc->sc_swflags, COM_SW_CLOCAL))
276 			SET(tp->t_cflag, CLOCAL);
277 		if (ISSET(sc->sc_swflags, COM_SW_CRTSCTS))
278 			SET(tp->t_cflag, CRTSCTS);
279 		if (ISSET(sc->sc_swflags, COM_SW_MDMBUF))
280 			SET(tp->t_cflag, MDMBUF);
281 		tp->t_lflag = TTYDEF_LFLAG;
282 
283 		s = spltty();
284 
285 		sc->sc_initialize = 1;
286 		comparam(tp, &tp->t_termios);
287 		ttsetwater(tp);
288 
289 		sc->sc_ibufp = sc->sc_ibuf = sc->sc_ibufs[0];
290 		sc->sc_ibufhigh = sc->sc_ibuf + COM_IHIGHWATER;
291 		sc->sc_ibufend = sc->sc_ibuf + COM_IBUFSIZE;
292 
293 		/*
294 		 * Wake up the sleepy heads.
295 		 */
296 		if (!ISSET(sc->sc_hwflags, COM_HW_CONSOLE)) {
297 			switch (sc->sc_uarttype) {
298 			case COM_UART_ST16650:
299 			case COM_UART_ST16650V2:
300 				com_write_reg(sc, com_lcr, LCR_EFR);
301 				com_write_reg(sc, com_efr, EFR_ECB);
302 				com_write_reg(sc, com_ier, 0);
303 				com_write_reg(sc, com_efr, 0);
304 				com_write_reg(sc, com_lcr, 0);
305 				break;
306 			case COM_UART_TI16750:
307 				com_write_reg(sc, com_ier, 0);
308 				break;
309 			}
310 		}
311 
312 		if (ISSET(sc->sc_hwflags, COM_HW_FIFO)) {
313 			u_int8_t fifo = FIFO_ENABLE|FIFO_RCV_RST|FIFO_XMT_RST;
314 			u_int8_t lcr;
315 
316 			if (tp->t_ispeed <= 1200)
317 				fifo |= FIFO_TRIGGER_1;
318 			else if (tp->t_ispeed <= 38400)
319 				fifo |= FIFO_TRIGGER_4;
320 			else
321 				fifo |= FIFO_TRIGGER_8;
322 			if (sc->sc_uarttype == COM_UART_TI16750) {
323 				fifo |= FIFO_ENABLE_64BYTE;
324 				lcr = com_read_reg(sc, com_lcr);
325 				com_write_reg(sc, com_lcr,
326 				    lcr | LCR_DLAB);
327 			}
328 
329 			/*
330 			 * (Re)enable and drain FIFOs.
331 			 *
332 			 * Certain SMC chips cause problems if the FIFOs are
333 			 * enabled while input is ready. Turn off the FIFO
334 			 * if necessary to clear the input. Test the input
335 			 * ready bit after enabling the FIFOs to handle races
336 			 * between enabling and fresh input.
337 			 *
338 			 * Set the FIFO threshold based on the receive speed.
339 			 */
340 			for (;;) {
341 				com_write_reg(sc, com_fifo, 0);
342 				delay(100);
343 				(void) com_read_reg(sc, com_data);
344 				com_write_reg(sc, com_fifo, fifo |
345 				    FIFO_RCV_RST | FIFO_XMT_RST);
346 				delay(100);
347 				if(!ISSET(com_read_reg(sc,
348 				    com_lsr), LSR_RXRDY))
349 					break;
350 			}
351 			if (sc->sc_uarttype == COM_UART_TI16750)
352 				com_write_reg(sc, com_lcr, lcr);
353 		}
354 
355 		/* Flush any pending I/O. */
356 		while (ISSET(com_read_reg(sc, com_lsr), LSR_RXRDY))
357 			(void) com_read_reg(sc, com_data);
358 
359 		/* You turn me on, baby! */
360 		sc->sc_mcr = MCR_DTR | MCR_RTS;
361 		if (!ISSET(sc->sc_hwflags, COM_HW_NOIEN))
362 			SET(sc->sc_mcr, MCR_IENABLE);
363 		com_write_reg(sc, com_mcr, sc->sc_mcr);
364 		sc->sc_ier = IER_ERXRDY | IER_ERLS | IER_EMSC;
365 		com_write_reg(sc, com_ier, sc->sc_ier);
366 
367 		sc->sc_msr = com_read_reg(sc, com_msr);
368 		if (ISSET(sc->sc_swflags, COM_SW_SOFTCAR) || DEVCUA(dev) ||
369 		    ISSET(sc->sc_msr, MSR_DCD) || ISSET(tp->t_cflag, MDMBUF))
370 			SET(tp->t_state, TS_CARR_ON);
371 		else
372 			CLR(tp->t_state, TS_CARR_ON);
373 	} else if (ISSET(tp->t_state, TS_XCLUDE) && suser(p) != 0)
374 		return EBUSY;
375 	else
376 		s = spltty();
377 
378 	if (DEVCUA(dev)) {
379 		if (ISSET(tp->t_state, TS_ISOPEN)) {
380 			/* Ah, but someone already is dialed in... */
381 			splx(s);
382 			return EBUSY;
383 		}
384 		sc->sc_cua = 1;		/* We go into CUA mode. */
385 	} else {
386 		/* tty (not cua) device; wait for carrier if necessary. */
387 		if (ISSET(flag, O_NONBLOCK)) {
388 			if (sc->sc_cua) {
389 				/* Opening TTY non-blocking... but the CUA is busy. */
390 				splx(s);
391 				return EBUSY;
392 			}
393 		} else {
394 			while (sc->sc_cua ||
395 			    (!ISSET(tp->t_cflag, CLOCAL) &&
396 				!ISSET(tp->t_state, TS_CARR_ON))) {
397 				SET(tp->t_state, TS_WOPEN);
398 				error = ttysleep(tp, &tp->t_rawq, TTIPRI | PCATCH, ttopen);
399 				/*
400 				 * If TS_WOPEN has been reset, that means the cua device
401 				 * has been closed.  We don't want to fail in that case,
402 				 * so just go around again.
403 				 */
404 				if (error && ISSET(tp->t_state, TS_WOPEN)) {
405 					CLR(tp->t_state, TS_WOPEN);
406 					if (!sc->sc_cua && !ISSET(tp->t_state, TS_ISOPEN))
407 						compwroff(sc);
408 					splx(s);
409 					return error;
410 				}
411 			}
412 		}
413 	}
414 	splx(s);
415 
416 	return (*linesw[tp->t_line].l_open)(dev, tp, p);
417 }
418 
419 int
420 comclose(dev_t dev, int flag, int mode, struct proc *p)
421 {
422 	int unit = DEVUNIT(dev);
423 	struct com_softc *sc = com_cd.cd_devs[unit];
424 	struct tty *tp = sc->sc_tty;
425 	int s;
426 
427 #ifdef COM_CONSOLE
428 	/* XXX This is for cons.c. */
429 	if (!ISSET(tp->t_state, TS_ISOPEN))
430 		return 0;
431 #endif
432 
433 	if(sc->sc_swflags & COM_SW_DEAD)
434 		return 0;
435 
436 	(*linesw[tp->t_line].l_close)(tp, flag, p);
437 	s = spltty();
438 	if (ISSET(tp->t_state, TS_WOPEN)) {
439 		/* tty device is waiting for carrier; drop dtr then re-raise */
440 		CLR(sc->sc_mcr, MCR_DTR | MCR_RTS);
441 		com_write_reg(sc, com_mcr, sc->sc_mcr);
442 		timeout_add_sec(&sc->sc_dtr_tmo, 2);
443 	} else {
444 		/* no one else waiting; turn off the uart */
445 		compwroff(sc);
446 	}
447 	CLR(tp->t_state, TS_BUSY | TS_FLUSH);
448 	sc->sc_cua = 0;
449 	splx(s);
450 	ttyclose(tp);
451 
452 #ifdef COM_CONSOLE
453 #ifdef notyet /* XXXX */
454 	if (ISSET(sc->sc_hwflags, COM_HW_CONSOLE)) {
455 		ttyfree(tp);
456 		sc->sc_tty = 0;
457 	}
458 #endif
459 #endif
460 	return 0;
461 }
462 
463 void
464 compwroff(struct com_softc *sc)
465 {
466 	struct tty *tp = sc->sc_tty;
467 
468 	CLR(sc->sc_lcr, LCR_SBREAK);
469 	com_write_reg(sc, com_lcr, sc->sc_lcr);
470 	com_write_reg(sc, com_ier, 0);
471 	if (ISSET(tp->t_cflag, HUPCL) &&
472 	    !ISSET(sc->sc_swflags, COM_SW_SOFTCAR)) {
473 		/* XXX perhaps only clear DTR */
474 		sc->sc_mcr = 0;
475 		com_write_reg(sc, com_mcr, sc->sc_mcr);
476 	}
477 
478 	/*
479 	 * Turn FIFO off; enter sleep mode if possible.
480 	 */
481 	com_write_reg(sc, com_fifo, 0);
482 	delay(100);
483 	if (ISSET(com_read_reg(sc, com_lsr), LSR_RXRDY))
484 		(void) com_read_reg(sc, com_data);
485 	delay(100);
486 	com_write_reg(sc, com_fifo,
487 			  FIFO_RCV_RST | FIFO_XMT_RST);
488 
489 	if (!ISSET(sc->sc_hwflags, COM_HW_CONSOLE)) {
490 		switch (sc->sc_uarttype) {
491 		case COM_UART_ST16650:
492 		case COM_UART_ST16650V2:
493 			com_write_reg(sc, com_lcr, LCR_EFR);
494 			com_write_reg(sc, com_efr, EFR_ECB);
495 			com_write_reg(sc, com_ier, IER_SLEEP);
496 			com_write_reg(sc, com_lcr, 0);
497 			break;
498 		case COM_UART_TI16750:
499 			com_write_reg(sc, com_ier, IER_SLEEP);
500 			break;
501 		}
502 	}
503 }
504 
505 void
506 com_resume(struct com_softc *sc)
507 {
508 	struct tty *tp = sc->sc_tty;
509 	int ospeed;
510 
511 	if (!tp || !ISSET(tp->t_state, TS_ISOPEN)) {
512 #ifdef COM_CONSOLE
513 		if (ISSET(sc->sc_hwflags, COM_HW_CONSOLE))
514 			cominit(comconsiot, comconsioh, comconsrate,
515 			    comconsfreq);
516 #endif
517 		return;
518 	}
519 
520 	/*
521 	 * Wake up the sleepy heads.
522 	 */
523 	if (!ISSET(sc->sc_hwflags, COM_HW_CONSOLE)) {
524 		switch (sc->sc_uarttype) {
525 		case COM_UART_ST16650:
526 		case COM_UART_ST16650V2:
527 			com_write_reg(sc, com_lcr, LCR_EFR);
528 			com_write_reg(sc, com_efr, EFR_ECB);
529 			com_write_reg(sc, com_ier, 0);
530 			com_write_reg(sc, com_efr, 0);
531 			com_write_reg(sc, com_lcr, 0);
532 			break;
533 		case COM_UART_TI16750:
534 			com_write_reg(sc, com_ier, 0);
535 			break;
536 		}
537 	}
538 
539 	ospeed = comspeed(sc->sc_frequency, tp->t_ospeed);
540 
541 	if (ospeed != 0) {
542 		com_write_reg(sc, com_lcr, sc->sc_lcr | LCR_DLAB);
543 		com_write_reg(sc, com_dlbl, ospeed);
544 		com_write_reg(sc, com_dlbh, ospeed >> 8);
545 		com_write_reg(sc, com_lcr, sc->sc_lcr);
546 	} else {
547 		com_write_reg(sc, com_lcr, sc->sc_lcr);
548 	}
549 
550 	if (ISSET(sc->sc_hwflags, COM_HW_FIFO)) {
551 		u_int8_t fifo = FIFO_ENABLE|FIFO_RCV_RST|FIFO_XMT_RST;
552 		u_int8_t lcr;
553 
554 		if (tp->t_ispeed <= 1200)
555 			fifo |= FIFO_TRIGGER_1;
556 		else if (tp->t_ispeed <= 38400)
557 			fifo |= FIFO_TRIGGER_4;
558 		else
559 			fifo |= FIFO_TRIGGER_8;
560 		if (sc->sc_uarttype == COM_UART_TI16750) {
561 			fifo |= FIFO_ENABLE_64BYTE;
562 			lcr = com_read_reg(sc, com_lcr);
563 			com_write_reg(sc, com_lcr,
564 			    lcr | LCR_DLAB);
565 		}
566 
567 		/*
568 		 * (Re)enable and drain FIFOs.
569 		 *
570 		 * Certain SMC chips cause problems if the FIFOs are
571 		 * enabled while input is ready. Turn off the FIFO
572 		 * if necessary to clear the input. Test the input
573 		 * ready bit after enabling the FIFOs to handle races
574 		 * between enabling and fresh input.
575 		 *
576 		 * Set the FIFO threshold based on the receive speed.
577 		 */
578 		for (;;) {
579 			com_write_reg(sc, com_fifo, 0);
580 			delay(100);
581 			(void) com_read_reg(sc, com_data);
582 			com_write_reg(sc, com_fifo, fifo |
583 			    FIFO_RCV_RST | FIFO_XMT_RST);
584 			delay(100);
585 			if(!ISSET(com_read_reg(sc,
586 			    com_lsr), LSR_RXRDY))
587 				break;
588 		}
589 		if (sc->sc_uarttype == COM_UART_TI16750)
590 			com_write_reg(sc, com_lcr, lcr);
591 	}
592 
593 	/* You turn me on, baby! */
594 	com_write_reg(sc, com_mcr, sc->sc_mcr);
595 	com_write_reg(sc, com_ier, sc->sc_ier);
596 }
597 
598 void
599 com_raisedtr(void *arg)
600 {
601 	struct com_softc *sc = arg;
602 
603 	SET(sc->sc_mcr, MCR_DTR | MCR_RTS);
604 	com_write_reg(sc, com_mcr, sc->sc_mcr);
605 }
606 
607 int
608 comread(dev_t dev, struct uio *uio, int flag)
609 {
610 	struct com_softc *sc = com_cd.cd_devs[DEVUNIT(dev)];
611 	struct tty *tp = sc->sc_tty;
612 
613 	return ((*linesw[tp->t_line].l_read)(tp, uio, flag));
614 }
615 
616 int
617 comwrite(dev_t dev, struct uio *uio, int flag)
618 {
619 	struct com_softc *sc = com_cd.cd_devs[DEVUNIT(dev)];
620 	struct tty *tp = sc->sc_tty;
621 
622 	return ((*linesw[tp->t_line].l_write)(tp, uio, flag));
623 }
624 
625 struct tty *
626 comtty(dev_t dev)
627 {
628 	struct com_softc *sc = com_cd.cd_devs[DEVUNIT(dev)];
629 	struct tty *tp = sc->sc_tty;
630 
631 	return (tp);
632 }
633 
634 static u_char
635 tiocm_xxx2mcr(int data)
636 {
637 	u_char m = 0;
638 
639 	if (ISSET(data, TIOCM_DTR))
640 		SET(m, MCR_DTR);
641 	if (ISSET(data, TIOCM_RTS))
642 		SET(m, MCR_RTS);
643 	return m;
644 }
645 
646 int
647 comioctl(dev_t dev, u_long cmd, caddr_t data, int flag, struct proc *p)
648 {
649 	int unit = DEVUNIT(dev);
650 	struct com_softc *sc = com_cd.cd_devs[unit];
651 	struct tty *tp = sc->sc_tty;
652 	int error;
653 
654 	error = (*linesw[tp->t_line].l_ioctl)(tp, cmd, data, flag, p);
655 	if (error >= 0)
656 		return error;
657 	error = ttioctl(tp, cmd, data, flag, p);
658 	if (error >= 0)
659 		return error;
660 
661 	switch (cmd) {
662 	case TIOCSBRK:
663 		SET(sc->sc_lcr, LCR_SBREAK);
664 		com_write_reg(sc, com_lcr, sc->sc_lcr);
665 		break;
666 	case TIOCCBRK:
667 		CLR(sc->sc_lcr, LCR_SBREAK);
668 		com_write_reg(sc, com_lcr, sc->sc_lcr);
669 		break;
670 	case TIOCSDTR:
671 		SET(sc->sc_mcr, sc->sc_dtr);
672 		com_write_reg(sc, com_mcr, sc->sc_mcr);
673 		break;
674 	case TIOCCDTR:
675 		CLR(sc->sc_mcr, sc->sc_dtr);
676 		com_write_reg(sc, com_mcr, sc->sc_mcr);
677 		break;
678 	case TIOCMSET:
679 		CLR(sc->sc_mcr, MCR_DTR | MCR_RTS);
680 	case TIOCMBIS:
681 		SET(sc->sc_mcr, tiocm_xxx2mcr(*(int *)data));
682 		com_write_reg(sc, com_mcr, sc->sc_mcr);
683 		break;
684 	case TIOCMBIC:
685 		CLR(sc->sc_mcr, tiocm_xxx2mcr(*(int *)data));
686 		com_write_reg(sc, com_mcr, sc->sc_mcr);
687 		break;
688 	case TIOCMGET: {
689 		u_char m;
690 		int bits = 0;
691 
692 		m = sc->sc_mcr;
693 		if (ISSET(m, MCR_DTR))
694 			SET(bits, TIOCM_DTR);
695 		if (ISSET(m, MCR_RTS))
696 			SET(bits, TIOCM_RTS);
697 		m = sc->sc_msr;
698 		if (ISSET(m, MSR_DCD))
699 			SET(bits, TIOCM_CD);
700 		if (ISSET(m, MSR_CTS))
701 			SET(bits, TIOCM_CTS);
702 		if (ISSET(m, MSR_DSR))
703 			SET(bits, TIOCM_DSR);
704 		if (ISSET(m, MSR_RI | MSR_TERI))
705 			SET(bits, TIOCM_RI);
706 		if (com_read_reg(sc, com_ier))
707 			SET(bits, TIOCM_LE);
708 		*(int *)data = bits;
709 		break;
710 	}
711 	case TIOCGFLAGS: {
712 		int driverbits, userbits = 0;
713 
714 		driverbits = sc->sc_swflags;
715 		if (ISSET(driverbits, COM_SW_SOFTCAR))
716 			SET(userbits, TIOCFLAG_SOFTCAR);
717 		if (ISSET(driverbits, COM_SW_CLOCAL))
718 			SET(userbits, TIOCFLAG_CLOCAL);
719 		if (ISSET(driverbits, COM_SW_CRTSCTS))
720 			SET(userbits, TIOCFLAG_CRTSCTS);
721 		if (ISSET(driverbits, COM_SW_MDMBUF))
722 			SET(userbits, TIOCFLAG_MDMBUF);
723 		if (ISSET(driverbits, COM_SW_PPS))
724 			SET(userbits, TIOCFLAG_PPS);
725 
726 		*(int *)data = userbits;
727 		break;
728 	}
729 	case TIOCSFLAGS: {
730 		int userbits, driverbits = 0;
731 
732 		error = suser(p);
733 		if (error != 0)
734 			return(EPERM);
735 
736 		userbits = *(int *)data;
737 		if (ISSET(userbits, TIOCFLAG_SOFTCAR) ||
738 		    ISSET(sc->sc_hwflags, COM_HW_CONSOLE))
739 			SET(driverbits, COM_SW_SOFTCAR);
740 		if (ISSET(userbits, TIOCFLAG_CLOCAL))
741 			SET(driverbits, COM_SW_CLOCAL);
742 		if (ISSET(userbits, TIOCFLAG_CRTSCTS))
743 			SET(driverbits, COM_SW_CRTSCTS);
744 		if (ISSET(userbits, TIOCFLAG_MDMBUF))
745 			SET(driverbits, COM_SW_MDMBUF);
746 		if (ISSET(userbits, TIOCFLAG_PPS))
747 			SET(driverbits, COM_SW_PPS);
748 
749 		sc->sc_swflags = driverbits;
750 		break;
751 	}
752 	default:
753 		return ENOTTY;
754 	}
755 
756 	return 0;
757 }
758 
759 /* already called at spltty */
760 int
761 comparam(struct tty *tp, struct termios *t)
762 {
763 	struct com_softc *sc = com_cd.cd_devs[DEVUNIT(tp->t_dev)];
764 	int ospeed = comspeed(sc->sc_frequency, t->c_ospeed);
765 	u_char lcr;
766 	tcflag_t oldcflag;
767 
768 	/* Check requested parameters. */
769 	if (ospeed < 0 || (t->c_ispeed && t->c_ispeed != t->c_ospeed))
770 		return EINVAL;
771 
772 	lcr = ISSET(sc->sc_lcr, LCR_SBREAK);
773 
774 	switch (ISSET(t->c_cflag, CSIZE)) {
775 	case CS5:
776 		SET(lcr, LCR_5BITS);
777 		break;
778 	case CS6:
779 		SET(lcr, LCR_6BITS);
780 		break;
781 	case CS7:
782 		SET(lcr, LCR_7BITS);
783 		break;
784 	case CS8:
785 		SET(lcr, LCR_8BITS);
786 		break;
787 	}
788 	if (ISSET(t->c_cflag, PARENB)) {
789 		SET(lcr, LCR_PENAB);
790 		if (!ISSET(t->c_cflag, PARODD))
791 			SET(lcr, LCR_PEVEN);
792 	}
793 	if (ISSET(t->c_cflag, CSTOPB))
794 		SET(lcr, LCR_STOPB);
795 
796 	sc->sc_lcr = lcr;
797 
798 	if (ospeed == 0) {
799 		CLR(sc->sc_mcr, MCR_DTR);
800 		com_write_reg(sc, com_mcr, sc->sc_mcr);
801 	}
802 
803 	/*
804 	 * Set the FIFO threshold based on the receive speed, if we are
805 	 * changing it.
806 	 */
807 	if (sc->sc_initialize || (tp->t_ispeed != t->c_ispeed)) {
808 		sc->sc_initialize = 0;
809 
810 		if (ospeed != 0) {
811 			/*
812 			 * Make sure the transmit FIFO is empty before
813 			 * proceeding.  If we don't do this, some revisions
814 			 * of the UART will hang.  Interestingly enough,
815 			 * even if we do this while the last character is
816 			 * still being pushed out, they don't hang.  This
817 			 * seems good enough.
818 			 */
819 			while (ISSET(tp->t_state, TS_BUSY)) {
820 				int error;
821 
822 				++sc->sc_halt;
823 				error = ttysleep(tp, &tp->t_outq,
824 				    TTOPRI | PCATCH, "comprm");
825 				--sc->sc_halt;
826 				if (error) {
827 					comstart(tp);
828 					return (error);
829 				}
830 			}
831 
832 			com_write_reg(sc, com_lcr, lcr | LCR_DLAB);
833 			com_write_reg(sc, com_dlbl, ospeed);
834 			com_write_reg(sc, com_dlbh, ospeed >> 8);
835 			com_write_reg(sc, com_lcr, lcr);
836 			SET(sc->sc_mcr, MCR_DTR);
837 			com_write_reg(sc, com_mcr, sc->sc_mcr);
838 		} else
839 			com_write_reg(sc, com_lcr, lcr);
840 
841 		if (ISSET(sc->sc_hwflags, COM_HW_FIFO)) {
842 			if (sc->sc_uarttype == COM_UART_TI16750) {
843 				com_write_reg(sc, com_lcr,
844 				    lcr | LCR_DLAB);
845 				com_write_reg(sc, com_fifo,
846 				    FIFO_ENABLE | FIFO_ENABLE_64BYTE |
847 				    (t->c_ispeed <= 1200 ? FIFO_TRIGGER_1 : FIFO_TRIGGER_8));
848 				com_write_reg(sc, com_lcr, lcr);
849 			} else
850 				com_write_reg(sc, com_fifo,
851 				    FIFO_ENABLE |
852 				    (t->c_ispeed <= 1200 ? FIFO_TRIGGER_1 : FIFO_TRIGGER_8));
853 		}
854 	} else
855 		com_write_reg(sc, com_lcr, lcr);
856 
857 	/* When not using CRTSCTS, RTS follows DTR. */
858 	if (!ISSET(t->c_cflag, CRTSCTS)) {
859 		if (ISSET(sc->sc_mcr, MCR_DTR)) {
860 			if (!ISSET(sc->sc_mcr, MCR_RTS)) {
861 				SET(sc->sc_mcr, MCR_RTS);
862 				com_write_reg(sc, com_mcr, sc->sc_mcr);
863 			}
864 		} else {
865 			if (ISSET(sc->sc_mcr, MCR_RTS)) {
866 				CLR(sc->sc_mcr, MCR_RTS);
867 				com_write_reg(sc, com_mcr, sc->sc_mcr);
868 			}
869 		}
870 		sc->sc_dtr = MCR_DTR | MCR_RTS;
871 	} else
872 		sc->sc_dtr = MCR_DTR;
873 
874 	/* and copy to tty */
875 	tp->t_ispeed = t->c_ispeed;
876 	tp->t_ospeed = t->c_ospeed;
877 	oldcflag = tp->t_cflag;
878 	tp->t_cflag = t->c_cflag;
879 
880 	/*
881 	 * If DCD is off and MDMBUF is changed, ask the tty layer if we should
882 	 * stop the device.
883 	 */
884 	if (!ISSET(sc->sc_msr, MSR_DCD) &&
885 	    !ISSET(sc->sc_swflags, COM_SW_SOFTCAR) &&
886 	    ISSET(oldcflag, MDMBUF) != ISSET(tp->t_cflag, MDMBUF) &&
887 	    (*linesw[tp->t_line].l_modem)(tp, 0) == 0) {
888 		CLR(sc->sc_mcr, sc->sc_dtr);
889 		com_write_reg(sc, com_mcr, sc->sc_mcr);
890 	}
891 
892 	/* Just to be sure... */
893 	comstart(tp);
894 	return 0;
895 }
896 
897 void
898 comstart(struct tty *tp)
899 {
900 	struct com_softc *sc = com_cd.cd_devs[DEVUNIT(tp->t_dev)];
901 	int s;
902 
903 	s = spltty();
904 	if (ISSET(tp->t_state, TS_BUSY))
905 		goto out;
906 	if (ISSET(tp->t_state, TS_TIMEOUT | TS_TTSTOP) || sc->sc_halt > 0)
907 		goto stopped;
908 	if (ISSET(tp->t_cflag, CRTSCTS) && !ISSET(sc->sc_msr, MSR_CTS))
909 		goto stopped;
910 	ttwakeupwr(tp);
911 	if (tp->t_outq.c_cc == 0)
912 		goto stopped;
913 	SET(tp->t_state, TS_BUSY);
914 
915 	/* Enable transmit completion interrupts. */
916 	if (!ISSET(sc->sc_ier, IER_ETXRDY)) {
917 		SET(sc->sc_ier, IER_ETXRDY);
918 		com_write_reg(sc, com_ier, sc->sc_ier);
919 	}
920 
921 	if (ISSET(sc->sc_hwflags, COM_HW_FIFO)) {
922 		u_char buffer[128];	/* largest fifo */
923 		int i, n;
924 
925 		n = q_to_b(&tp->t_outq, buffer,
926 		    min(sc->sc_fifolen, sizeof buffer));
927 		for (i = 0; i < n; i++) {
928 			com_write_reg(sc, com_data, buffer[i]);
929 		}
930 		bzero(buffer, n);
931 	} else if (tp->t_outq.c_cc != 0)
932 		com_write_reg(sc, com_data, getc(&tp->t_outq));
933 out:
934 	splx(s);
935 	return;
936 stopped:
937 	if (ISSET(sc->sc_ier, IER_ETXRDY)) {
938 		CLR(sc->sc_ier, IER_ETXRDY);
939 		com_write_reg(sc, com_ier, sc->sc_ier);
940 	}
941 	splx(s);
942 }
943 
944 /*
945  * Stop output on a line.
946  */
947 int
948 comstop(struct tty *tp, int flag)
949 {
950 	int s;
951 
952 	s = spltty();
953 	if (ISSET(tp->t_state, TS_BUSY))
954 		if (!ISSET(tp->t_state, TS_TTSTOP))
955 			SET(tp->t_state, TS_FLUSH);
956 	splx(s);
957 	return 0;
958 }
959 
960 void
961 comdiag(void *arg)
962 {
963 	struct com_softc *sc = arg;
964 	int overflows, floods;
965 	int s;
966 
967 	s = spltty();
968 	sc->sc_errors = 0;
969 	overflows = sc->sc_overflows;
970 	sc->sc_overflows = 0;
971 	floods = sc->sc_floods;
972 	sc->sc_floods = 0;
973 	splx(s);
974 	log(LOG_WARNING, "%s: %d silo overflow%s, %d ibuf overflow%s\n",
975 	    sc->sc_dev.dv_xname,
976 	    overflows, overflows == 1 ? "" : "s",
977 	    floods, floods == 1 ? "" : "s");
978 }
979 
980 void
981 comsoft(void *arg)
982 {
983 	struct com_softc *sc = (struct com_softc *)arg;
984 	struct tty *tp;
985 	u_char *ibufp;
986 	u_char *ibufend;
987 	int c;
988 	int s;
989 	static int lsrmap[8] = {
990 		0,      TTY_PE,
991 		TTY_FE, TTY_PE|TTY_FE,
992 		TTY_FE, TTY_PE|TTY_FE,
993 		TTY_FE, TTY_PE|TTY_FE
994 	};
995 
996 	if (sc == NULL || sc->sc_ibufp == sc->sc_ibuf)
997 		return;
998 
999 	tp = sc->sc_tty;
1000 
1001 	s = spltty();
1002 
1003 	ibufp = sc->sc_ibuf;
1004 	ibufend = sc->sc_ibufp;
1005 
1006 	if (ibufp == ibufend) {
1007 		splx(s);
1008 		return;
1009 	}
1010 
1011 	sc->sc_ibufp = sc->sc_ibuf = (ibufp == sc->sc_ibufs[0]) ?
1012 				     sc->sc_ibufs[1] : sc->sc_ibufs[0];
1013 	sc->sc_ibufhigh = sc->sc_ibuf + COM_IHIGHWATER;
1014 	sc->sc_ibufend = sc->sc_ibuf + COM_IBUFSIZE;
1015 
1016 	if (tp == NULL || !ISSET(tp->t_state, TS_ISOPEN)) {
1017 		splx(s);
1018 		return;
1019 	}
1020 
1021 	if (ISSET(tp->t_cflag, CRTSCTS) &&
1022 	    !ISSET(sc->sc_mcr, MCR_RTS)) {
1023 		/* XXX */
1024 		SET(sc->sc_mcr, MCR_RTS);
1025 		com_write_reg(sc, com_mcr, sc->sc_mcr);
1026 	}
1027 
1028 	splx(s);
1029 
1030 	while (ibufp < ibufend) {
1031 		c = *ibufp++;
1032 		if (ISSET(*ibufp, LSR_OE)) {
1033 			sc->sc_overflows++;
1034 			if (sc->sc_errors++ == 0)
1035 				timeout_add_sec(&sc->sc_diag_tmo, 60);
1036 		}
1037 		/* This is ugly, but fast. */
1038 		c |= lsrmap[(*ibufp++ & (LSR_BI|LSR_FE|LSR_PE)) >> 2];
1039 		(*linesw[tp->t_line].l_rint)(c, tp);
1040 	}
1041 }
1042 
1043 int
1044 comintr(void *arg)
1045 {
1046 	struct com_softc *sc = arg;
1047 	struct tty *tp;
1048 	u_char lsr, data, msr, delta;
1049 
1050 	if (!sc->sc_tty)
1051 		return (0);		/* Can't do squat. */
1052 
1053 	if (ISSET(com_read_reg(sc, com_iir), IIR_NOPEND))
1054 		return (0);
1055 
1056 	tp = sc->sc_tty;
1057 
1058 	for (;;) {
1059 		lsr = com_read_reg(sc, com_lsr);
1060 
1061 		if (ISSET(lsr, LSR_RXRDY)) {
1062 			u_char *p = sc->sc_ibufp;
1063 
1064 			softintr_schedule(sc->sc_si);
1065 			do {
1066 				data = com_read_reg(sc, com_data);
1067 				if (ISSET(lsr, LSR_BI)) {
1068 #if defined(COM_CONSOLE) && defined(DDB)
1069 					if (ISSET(sc->sc_hwflags,
1070 					    COM_HW_CONSOLE)) {
1071 						if (db_console)
1072 							db_enter();
1073 						goto next;
1074 					}
1075 #endif
1076 					data = 0;
1077 				}
1078 				if (p >= sc->sc_ibufend) {
1079 					sc->sc_floods++;
1080 					if (sc->sc_errors++ == 0)
1081 						timeout_add_sec(&sc->sc_diag_tmo, 60);
1082 				} else {
1083 					*p++ = data;
1084 					*p++ = lsr;
1085 					if (p == sc->sc_ibufhigh &&
1086 					    ISSET(tp->t_cflag, CRTSCTS)) {
1087 						/* XXX */
1088 						CLR(sc->sc_mcr, MCR_RTS);
1089 						com_write_reg(sc, com_mcr,
1090 						    sc->sc_mcr);
1091 					}
1092 				}
1093 #if defined(COM_CONSOLE) && defined(DDB)
1094 			next:
1095 #endif
1096 				lsr = com_read_reg(sc, com_lsr);
1097 			} while (ISSET(lsr, LSR_RXRDY));
1098 
1099 			sc->sc_ibufp = p;
1100 		}
1101 		msr = com_read_reg(sc, com_msr);
1102 
1103 		if (msr != sc->sc_msr) {
1104 			delta = msr ^ sc->sc_msr;
1105 
1106 			ttytstamp(tp, sc->sc_msr & MSR_CTS, msr & MSR_CTS,
1107 			    sc->sc_msr & MSR_DCD, msr & MSR_DCD);
1108 
1109 			sc->sc_msr = msr;
1110 			if (ISSET(delta, MSR_DCD)) {
1111 				if (!ISSET(sc->sc_swflags, COM_SW_SOFTCAR) &&
1112 				    (*linesw[tp->t_line].l_modem)(tp, ISSET(msr, MSR_DCD)) == 0) {
1113 					CLR(sc->sc_mcr, sc->sc_dtr);
1114 					com_write_reg(sc, com_mcr, sc->sc_mcr);
1115 				}
1116 			}
1117 			if (ISSET(delta & msr, MSR_CTS) &&
1118 			    ISSET(tp->t_cflag, CRTSCTS)) {
1119 				/* the line is up and we want to do rts/cts flow control */
1120 				(*linesw[tp->t_line].l_start)(tp);
1121 			}
1122 		}
1123 
1124 		if (ISSET(lsr, LSR_TXRDY) && ISSET(tp->t_state, TS_BUSY)) {
1125 			CLR(tp->t_state, TS_BUSY | TS_FLUSH);
1126 			if (sc->sc_halt > 0)
1127 				wakeup(&tp->t_outq);
1128 			(*linesw[tp->t_line].l_start)(tp);
1129 		}
1130 
1131 		if (ISSET(com_read_reg(sc, com_iir), IIR_NOPEND))
1132 			return (1);
1133 	}
1134 }
1135 
1136 void
1137 cominit(bus_space_tag_t iot, bus_space_handle_t ioh, int rate, int frequency)
1138 {
1139 	int s = splhigh();
1140 	u_char stat;
1141 
1142 	bus_space_write_1(iot, ioh, com_lcr, LCR_DLAB);
1143 	rate = comspeed(frequency, rate); /* XXX not comdefaultrate? */
1144 	bus_space_write_1(iot, ioh, com_dlbl, rate);
1145 	bus_space_write_1(iot, ioh, com_dlbh, rate >> 8);
1146 	bus_space_write_1(iot, ioh, com_lcr, LCR_8BITS);
1147 	bus_space_write_1(iot, ioh, com_mcr, MCR_DTR | MCR_RTS);
1148 	bus_space_write_1(iot, ioh, com_ier, 0);  /* Make sure they are off */
1149 	bus_space_write_1(iot, ioh, com_fifo,
1150 	    FIFO_ENABLE | FIFO_RCV_RST | FIFO_XMT_RST | FIFO_TRIGGER_1);
1151 	stat = bus_space_read_1(iot, ioh, com_iir);
1152 	splx(s);
1153 }
1154 
1155 #ifdef COM_CONSOLE
1156 void
1157 comcnprobe(struct consdev *cp)
1158 {
1159 	bus_space_handle_t ioh;
1160 	int found;
1161 
1162 	if (comconsaddr == 0)
1163 		return;
1164 
1165 	if (bus_space_map(comconsiot, comconsaddr, COM_NPORTS, 0, &ioh))
1166 		return;
1167 	found = comprobe1(comconsiot, ioh);
1168 	bus_space_unmap(comconsiot, ioh, COM_NPORTS);
1169 	if (!found)
1170 		return;
1171 
1172 	/* Locate the major number. */
1173 	for (commajor = 0; commajor < nchrdev; commajor++)
1174 		if (cdevsw[commajor].d_open == comopen)
1175 			break;
1176 
1177 	/* Initialize required fields. */
1178 	cp->cn_dev = makedev(commajor, comconsunit);
1179 	cp->cn_pri = CN_HIGHPRI;
1180 }
1181 
1182 void
1183 comcninit(struct consdev *cp)
1184 {
1185 	if (bus_space_map(comconsiot, comconsaddr, COM_NPORTS, 0, &comconsioh))
1186 		panic("comcninit: mapping failed");
1187 
1188 	if (comconsfreq == 0)
1189 		comconsfreq = COM_FREQ;
1190 
1191 	cominit(comconsiot, comconsioh, comconsrate, comconsfreq);
1192 }
1193 
1194 int
1195 comcnattach(bus_space_tag_t iot, bus_addr_t iobase, int rate,
1196     int frequency, tcflag_t cflag)
1197 {
1198 	static struct consdev comcons = {
1199 		NULL, NULL, comcngetc, comcnputc, comcnpollc, NULL,
1200 		NODEV, CN_LOWPRI
1201 	};
1202 
1203 #ifndef __sparc64__
1204 	if (bus_space_map(iot, iobase, COM_NPORTS, 0, &comconsioh))
1205 		return ENOMEM;
1206 #endif
1207 
1208 	cominit(iot, comconsioh, rate, frequency);
1209 
1210 	cn_tab = &comcons;
1211 
1212 	comconsiot = iot;
1213 	comconsaddr = iobase;
1214 	comconscflag = cflag;
1215 	comconsfreq = frequency;
1216 	comconsrate = rate;
1217 
1218 	return (0);
1219 }
1220 
1221 int
1222 comcngetc(dev_t dev)
1223 {
1224 	int s = splhigh();
1225 	u_char stat, c;
1226 
1227 	/* Block until a character becomes available. */
1228 	while (!ISSET(stat = comcn_read_reg(com_lsr), LSR_RXRDY))
1229 		continue;
1230 
1231 	c = comcn_read_reg(com_data);
1232 
1233 	/* Clear any interrupts generated by this transmission. */
1234 	stat = comcn_read_reg(com_iir);
1235 	splx(s);
1236 	return (c);
1237 }
1238 
1239 /*
1240  * Console kernel output character routine.
1241  */
1242 void
1243 comcnputc(dev_t dev, int c)
1244 {
1245 	int s = spltty();
1246 	int timo;
1247 
1248 	/* Wait for any pending transmission to finish. */
1249 	timo = 2000;
1250 	while (!ISSET(comcn_read_reg(com_lsr), LSR_TXRDY) && --timo)
1251 		delay(1);
1252 
1253 	comcn_write_reg(com_data, (u_int8_t)(c & 0xff));
1254 	bus_space_barrier(comconsiot, comconsioh, 0,
1255 	    COM_NPORTS << comcons_reg_shift,
1256 	    (BUS_SPACE_BARRIER_READ|BUS_SPACE_BARRIER_WRITE));
1257 
1258 	/* Wait for this transmission to complete. */
1259 	timo = 2000;
1260 	while (!ISSET(comcn_read_reg(com_lsr), LSR_TXRDY) && --timo)
1261 		delay(1);
1262 
1263 	splx(s);
1264 }
1265 
1266 void
1267 comcnpollc(dev_t dev, int on)
1268 {
1269 }
1270 #endif	/* COM_CONSOLE */
1271 
1272 void	com_enable_debugport(struct com_softc *);
1273 void	com_fifo_probe(struct com_softc *);
1274 
1275 #ifdef COM_CONSOLE
1276 void
1277 com_enable_debugport(struct com_softc *sc)
1278 {
1279 	int s;
1280 
1281 	/* Turn on line break interrupt, set carrier. */
1282 	s = splhigh();
1283 	SET(sc->sc_mcr, MCR_DTR | MCR_RTS | MCR_IENABLE);
1284 	com_write_reg(sc, com_mcr, sc->sc_mcr);
1285 
1286 	splx(s);
1287 }
1288 #endif	/* COM_CONSOLE */
1289 
1290 void
1291 com_attach_subr(struct com_softc *sc)
1292 {
1293 	int probe = 0;
1294 	u_int8_t lcr;
1295 
1296 	sc->sc_ier = 0;
1297 	/* disable interrupts */
1298 	com_write_reg(sc, com_ier, sc->sc_ier);
1299 
1300 #ifdef COM_CONSOLE
1301 	if (sc->sc_iot == comconsiot && sc->sc_iobase == comconsaddr) {
1302 		comconsattached = 1;
1303 		delay(10000);			/* wait for output to finish */
1304 		SET(sc->sc_hwflags, COM_HW_CONSOLE);
1305 		SET(sc->sc_swflags, COM_SW_SOFTCAR);
1306 	}
1307 #endif
1308 
1309 	/*
1310 	 * Probe for all known forms of UART.
1311 	 */
1312 	lcr = com_read_reg(sc, com_lcr);
1313 	com_write_reg(sc, com_lcr, LCR_EFR);
1314 	com_write_reg(sc, com_efr, 0);
1315 	com_write_reg(sc, com_lcr, 0);
1316 
1317 	com_write_reg(sc, com_fifo, FIFO_ENABLE);
1318 	delay(100);
1319 
1320 	/*
1321 	 * Skip specific probes if attachment code knows it already.
1322 	 */
1323 	if (sc->sc_uarttype == COM_UART_UNKNOWN) {
1324 		switch (com_read_reg(sc, com_iir) >> 6) {
1325 		case 0:
1326 			sc->sc_uarttype = COM_UART_16450;
1327 			break;
1328 		case 2:
1329 			sc->sc_uarttype = COM_UART_16550;
1330 			break;
1331 		case 3:
1332 			sc->sc_uarttype = COM_UART_16550A;
1333 			break;
1334 		default:
1335 			sc->sc_uarttype = COM_UART_UNKNOWN;
1336 			break;
1337 		}
1338 		probe = 1;
1339 	}
1340 
1341 	/* Probe for ST16650s */
1342 	if (probe && sc->sc_uarttype == COM_UART_16550A) {
1343 		com_write_reg(sc, com_lcr, lcr | LCR_DLAB);
1344 		if (com_read_reg(sc, com_efr) == 0) {
1345 			com_write_reg(sc, com_efr, EFR_CTS);
1346 			if (com_read_reg(sc, com_efr) != 0)
1347 				sc->sc_uarttype = COM_UART_ST16650;
1348 			com_write_reg(sc, com_efr, 0);
1349 		} else {
1350 			com_write_reg(sc, com_lcr, LCR_EFR);
1351 			if (com_read_reg(sc, com_efr) == 0)
1352 				sc->sc_uarttype = COM_UART_ST16650V2;
1353 		}
1354 	}
1355 
1356 #if 0	/* until com works with large FIFOs */
1357 	/* Probe for XR16850s */
1358 	if (probe && sc->sc_uarttype == COM_UART_ST16650V2) {
1359 		u_int8_t dlbl, dlbh;
1360 
1361 		/* Enable latch access and get the current values. */
1362 		com_write_reg(sc, com_lcr, lcr | LCR_DLAB);
1363 		dlbl = com_read_reg(sc, com_dlbl);
1364 		dlbh = com_read_reg(sc, com_dlbh);
1365 
1366 		/* Zero out the latch divisors */
1367 		com_write_reg(sc, com_dlbl, 0);
1368 		com_write_reg(sc, com_dlbh, 0);
1369 
1370 		if (com_read_reg(sc, com_dlbh) == 0x10) {
1371 			sc->sc_uarttype = COM_UART_XR16850;
1372 			sc->sc_uartrev = com_read_reg(sc, com_dlbl);
1373 		}
1374 
1375 		/* Reset to original. */
1376 		com_write_reg(sc, com_dlbl, dlbl);
1377 		com_write_reg(sc, com_dlbh, dlbh);
1378 	}
1379 #endif
1380 
1381 	/* Probe for TI16750s */
1382 	if (probe && sc->sc_uarttype == COM_UART_16550A) {
1383 		com_write_reg(sc, com_lcr, lcr | LCR_DLAB);
1384 		com_write_reg(sc, com_fifo,
1385 		    FIFO_ENABLE | FIFO_ENABLE_64BYTE);
1386 		if ((com_read_reg(sc, com_iir) >> 5) == 7) {
1387 #if 0
1388 			com_write_reg(sc, com_lcr, 0);
1389 			if ((com_read_reg(sc, com_iir) >> 5) == 6)
1390 #endif
1391 				sc->sc_uarttype = COM_UART_TI16750;
1392 		}
1393 		com_write_reg(sc, com_fifo, FIFO_ENABLE);
1394 	}
1395 
1396 	/* Reset the LCR (latch access is probably enabled). */
1397 	com_write_reg(sc, com_lcr, lcr);
1398 
1399 	/* Probe for 8250 */
1400 	if (probe && sc->sc_uarttype == COM_UART_16450) {
1401 		u_int8_t scr0, scr1, scr2;
1402 
1403 		scr0 = com_read_reg(sc, com_scratch);
1404 		com_write_reg(sc, com_scratch, 0xa5);
1405 		scr1 = com_read_reg(sc, com_scratch);
1406 		com_write_reg(sc, com_scratch, 0x5a);
1407 		scr2 = com_read_reg(sc, com_scratch);
1408 		com_write_reg(sc, com_scratch, scr0);
1409 
1410 		if ((scr1 != 0xa5) || (scr2 != 0x5a))
1411 			sc->sc_uarttype = COM_UART_8250;
1412 	}
1413 
1414 	/*
1415 	 * Print UART type and initialize ourself.
1416 	 */
1417 	switch (sc->sc_uarttype) {
1418 	case COM_UART_UNKNOWN:
1419 		printf(": unknown uart\n");
1420 		break;
1421 	case COM_UART_8250:
1422 		printf(": ns8250, no fifo\n");
1423 		break;
1424 	case COM_UART_16450:
1425 		printf(": ns16450, no fifo\n");
1426 		break;
1427 	case COM_UART_16550:
1428 		printf(": ns16550, no working fifo\n");
1429 		break;
1430 	case COM_UART_16550A:
1431 		if (sc->sc_fifolen == 0)
1432 			sc->sc_fifolen = 16;
1433 		printf(": ns16550a, %d byte fifo\n", sc->sc_fifolen);
1434 		SET(sc->sc_hwflags, COM_HW_FIFO);
1435 		break;
1436 	case COM_UART_ST16650:
1437 		printf(": st16650, no working fifo\n");
1438 		break;
1439 	case COM_UART_ST16650V2:
1440 		if (sc->sc_fifolen == 0)
1441 			sc->sc_fifolen = 32;
1442 		printf(": st16650, %d byte fifo\n", sc->sc_fifolen);
1443 		SET(sc->sc_hwflags, COM_HW_FIFO);
1444 		break;
1445 	case COM_UART_ST16C654:
1446 		printf(": st16c654, 64 byte fifo\n");
1447 		SET(sc->sc_hwflags, COM_HW_FIFO);
1448 		sc->sc_fifolen = 64;
1449 		break;
1450 	case COM_UART_TI16750:
1451 		printf(": ti16750, 64 byte fifo\n");
1452 		SET(sc->sc_hwflags, COM_HW_FIFO);
1453 		sc->sc_fifolen = 64;
1454 		break;
1455 #if 0
1456 	case COM_UART_XR16850:
1457 		printf(": xr16850 (rev %d), 128 byte fifo\n", sc->sc_uartrev);
1458 		SET(sc->sc_hwflags, COM_HW_FIFO);
1459 		sc->sc_fifolen = 128;
1460 		break;
1461 #ifdef COM_UART_OX16C950
1462 	case COM_UART_OX16C950:
1463 		printf(": ox16c950 (rev %d), 128 byte fifo\n", sc->sc_uartrev);
1464 		SET(sc->sc_hwflags, COM_HW_FIFO);
1465 		sc->sc_fifolen = 128;
1466 		break;
1467 #endif
1468 #endif
1469 	default:
1470 		panic("comattach: bad fifo type");
1471 	}
1472 
1473 #ifdef COM_CONSOLE
1474 	if (!ISSET(sc->sc_hwflags, COM_HW_CONSOLE))
1475 #endif
1476 		com_fifo_probe(sc);
1477 
1478 	if (sc->sc_fifolen == 0) {
1479 		CLR(sc->sc_hwflags, COM_HW_FIFO);
1480 		sc->sc_fifolen = 1;
1481 	}
1482 
1483 	/* clear and disable fifo */
1484 	com_write_reg(sc, com_fifo, FIFO_RCV_RST | FIFO_XMT_RST);
1485 	if (ISSET(com_read_reg(sc, com_lsr), LSR_RXRDY))
1486 		(void)com_read_reg(sc, com_data);
1487 	com_write_reg(sc, com_fifo, 0);
1488 
1489 	sc->sc_mcr = 0;
1490 	com_write_reg(sc, com_mcr, sc->sc_mcr);
1491 
1492 #ifdef COM_CONSOLE
1493 	if (ISSET(sc->sc_hwflags, COM_HW_CONSOLE)) {
1494 		int maj;
1495 
1496 		/* locate the major number */
1497 		for (maj = 0; maj < nchrdev; maj++)
1498 			if (cdevsw[maj].d_open == comopen)
1499 				break;
1500 
1501 		if (maj < nchrdev && cn_tab->cn_dev == NODEV)
1502 			cn_tab->cn_dev = makedev(maj, sc->sc_dev.dv_unit);
1503 
1504 		printf("%s: console\n", sc->sc_dev.dv_xname);
1505 	}
1506 #endif
1507 
1508 	timeout_set(&sc->sc_diag_tmo, comdiag, sc);
1509 	timeout_set(&sc->sc_dtr_tmo, com_raisedtr, sc);
1510 	sc->sc_si = softintr_establish(IPL_TTY, comsoft, sc);
1511 	if (sc->sc_si == NULL)
1512 		panic("%s: can't establish soft interrupt",
1513 		    sc->sc_dev.dv_xname);
1514 
1515 	/*
1516 	 * If there are no enable/disable functions, assume the device
1517 	 * is always enabled.
1518 	 */
1519 	if (!sc->enable)
1520 		sc->enabled = 1;
1521 
1522 #ifdef COM_CONSOLE
1523 	if (ISSET(sc->sc_hwflags, COM_HW_CONSOLE))
1524 		com_enable_debugport(sc);
1525 #endif
1526 }
1527 
1528 void
1529 com_fifo_probe(struct com_softc *sc)
1530 {
1531 	u_int8_t fifo, ier;
1532 	int timo, len;
1533 
1534 	if (!ISSET(sc->sc_hwflags, COM_HW_FIFO))
1535 		return;
1536 
1537 	ier = 0;
1538 	com_write_reg(sc, com_ier, ier);
1539 	com_write_reg(sc, com_lcr, LCR_DLAB);
1540 	com_write_reg(sc, com_dlbl, 3);
1541 	com_write_reg(sc, com_dlbh, 0);
1542 	com_write_reg(sc, com_lcr, LCR_PNONE | LCR_8BITS);
1543 	com_write_reg(sc, com_mcr, MCR_LOOPBACK);
1544 
1545 	fifo = FIFO_ENABLE | FIFO_RCV_RST | FIFO_XMT_RST;
1546 	if (sc->sc_uarttype == COM_UART_TI16750)
1547 		fifo |= FIFO_ENABLE_64BYTE;
1548 
1549 	com_write_reg(sc, com_fifo, fifo);
1550 
1551 	for (len = 0; len < 256; len++) {
1552 		com_write_reg(sc, com_data, (len + 1));
1553 		timo = 2000;
1554 		while (!ISSET(com_read_reg(sc, com_lsr),
1555 		    LSR_TXRDY) && --timo)
1556 			delay(1);
1557 		if (!timo)
1558 			break;
1559 	}
1560 
1561 	delay(100);
1562 
1563 	for (len = 0; len < 256; len++) {
1564 		timo = 2000;
1565 		while (!ISSET(com_read_reg(sc, com_lsr),
1566 		    LSR_RXRDY) && --timo)
1567 			delay(1);
1568 		if (!timo || com_read_reg(sc, com_data) != (len + 1))
1569 			break;
1570 	}
1571 
1572 	/* For safety, always use the smaller value. */
1573 	if (sc->sc_fifolen > len) {
1574 		printf("%s: probed fifo depth: %d bytes\n",
1575 		    sc->sc_dev.dv_xname, len);
1576 		sc->sc_fifolen = len;
1577 	}
1578 }
1579 
1580 uint8_t
1581 com_read_reg(struct com_softc *sc, bus_size_t reg)
1582 {
1583 	reg <<= sc->sc_reg_shift;
1584 
1585 	if (sc->sc_reg_width == 4)
1586 		return bus_space_read_4(sc->sc_iot, sc->sc_ioh, reg);
1587 	else
1588 		return bus_space_read_1(sc->sc_iot, sc->sc_ioh, reg);
1589 }
1590 
1591 void
1592 com_write_reg(struct com_softc *sc, bus_size_t reg, uint8_t value)
1593 {
1594 	reg <<= sc->sc_reg_shift;
1595 
1596 	if (sc->sc_reg_width == 4)
1597 		return bus_space_write_4(sc->sc_iot, sc->sc_ioh, reg, value);
1598 	else
1599 		return bus_space_write_1(sc->sc_iot, sc->sc_ioh, reg, value);
1600 }
1601 
1602 #ifdef COM_CONSOLE
1603 
1604 u_char comcons_reg_width;
1605 u_char comcons_reg_shift;
1606 
1607 uint8_t
1608 comcn_read_reg(bus_size_t reg)
1609 {
1610 	reg <<= comcons_reg_shift;
1611 
1612 	if (comcons_reg_width == 4)
1613 		return bus_space_read_4(comconsiot, comconsioh, reg);
1614 	else
1615 		return bus_space_read_1(comconsiot, comconsioh, reg);
1616 }
1617 
1618 void
1619 comcn_write_reg(bus_size_t reg, uint8_t value)
1620 {
1621 	reg <<= comcons_reg_shift;
1622 
1623 	if (comcons_reg_width == 4)
1624 		return bus_space_write_4(comconsiot, comconsioh, reg, value);
1625 	else
1626 		return bus_space_write_1(comconsiot, comconsioh, reg, value);
1627 }
1628 
1629 #endif
1630