xref: /netbsd-src/sys/arch/evbarm/dev/plcom.c (revision 274254cdae52594c1aa480a736aef78313d15c9c)
1 /*	$NetBSD: plcom.c,v 1.29 2009/03/14 15:36:05 dsl Exp $	*/
2 
3 /*-
4  * Copyright (c) 2001 ARM Ltd
5  * 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 company may not be used to endorse or promote
16  *    products derived from this software without specific prior written
17  *    permission.
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
20  * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
21  * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
22  * IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT,
23  * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
24  * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
25  * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29  * SUCH DAMAGE.
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  * COM driver for the Prime Cell PL010 UART, which is similar to the 16C550,
92  * but has a completely different programmer's model.
93  * Derived from the NS16550AF com driver.
94  */
95 
96 #include <sys/cdefs.h>
97 __KERNEL_RCSID(0, "$NetBSD: plcom.c,v 1.29 2009/03/14 15:36:05 dsl Exp $");
98 
99 #include "opt_plcom.h"
100 #include "opt_ddb.h"
101 #include "opt_kgdb.h"
102 #include "opt_lockdebug.h"
103 #include "opt_multiprocessor.h"
104 
105 #include "rnd.h"
106 #if NRND > 0 && defined(RND_COM)
107 #include <sys/rnd.h>
108 #endif
109 
110 /*
111  * Override cnmagic(9) macro before including <sys/systm.h>.
112  * We need to know if cn_check_magic triggered debugger, so set a flag.
113  * Callers of cn_check_magic must declare int cn_trapped = 0;
114  * XXX: this is *ugly*!
115  */
116 #define cn_trap()				\
117 	do {					\
118 		console_debugger();		\
119 		cn_trapped = 1;			\
120 	} while (/* CONSTCOND */ 0)
121 
122 #include <sys/param.h>
123 #include <sys/systm.h>
124 #include <sys/ioctl.h>
125 #include <sys/select.h>
126 #include <sys/tty.h>
127 #include <sys/proc.h>
128 #include <sys/user.h>
129 #include <sys/conf.h>
130 #include <sys/file.h>
131 #include <sys/uio.h>
132 #include <sys/kernel.h>
133 #include <sys/syslog.h>
134 #include <sys/types.h>
135 #include <sys/device.h>
136 #include <sys/malloc.h>
137 #include <sys/timepps.h>
138 #include <sys/vnode.h>
139 #include <sys/kauth.h>
140 #include <sys/intr.h>
141 #include <sys/bus.h>
142 
143 #include <evbarm/dev/plcomreg.h>
144 #include <evbarm/dev/plcomvar.h>
145 
146 #include <dev/cons.h>
147 
148 static void plcom_enable_debugport (struct plcom_softc *);
149 
150 void	plcom_config	(struct plcom_softc *);
151 void	plcom_shutdown	(struct plcom_softc *);
152 int	plcomspeed	(long, long);
153 static	u_char	cflag2lcr (tcflag_t);
154 int	plcomparam	(struct tty *, struct termios *);
155 void	plcomstart	(struct tty *);
156 int	plcomhwiflow	(struct tty *, int);
157 
158 void	plcom_loadchannelregs (struct plcom_softc *);
159 void	plcom_hwiflow	(struct plcom_softc *);
160 void	plcom_break	(struct plcom_softc *, int);
161 void	plcom_modem	(struct plcom_softc *, int);
162 void	tiocm_to_plcom	(struct plcom_softc *, u_long, int);
163 int	plcom_to_tiocm	(struct plcom_softc *);
164 void	plcom_iflush	(struct plcom_softc *);
165 
166 int	plcom_common_getc (dev_t, bus_space_tag_t, bus_space_handle_t);
167 void	plcom_common_putc (dev_t, bus_space_tag_t, bus_space_handle_t, int);
168 
169 int	plcominit	(bus_space_tag_t, bus_addr_t, int, int, tcflag_t,
170 			    bus_space_handle_t *);
171 
172 dev_type_open(plcomopen);
173 dev_type_close(plcomclose);
174 dev_type_read(plcomread);
175 dev_type_write(plcomwrite);
176 dev_type_ioctl(plcomioctl);
177 dev_type_stop(plcomstop);
178 dev_type_tty(plcomtty);
179 dev_type_poll(plcompoll);
180 
181 int	plcomcngetc	(dev_t);
182 void	plcomcnputc	(dev_t, int);
183 void	plcomcnpollc	(dev_t, int);
184 
185 #define	integrate	static inline
186 void 	plcomsoft	(void *);
187 integrate void plcom_rxsoft	(struct plcom_softc *, struct tty *);
188 integrate void plcom_txsoft	(struct plcom_softc *, struct tty *);
189 integrate void plcom_stsoft	(struct plcom_softc *, struct tty *);
190 integrate void plcom_schedrx	(struct plcom_softc *);
191 void	plcomdiag		(void *);
192 
193 extern struct cfdriver plcom_cd;
194 
195 const struct cdevsw plcom_cdevsw = {
196 	plcomopen, plcomclose, plcomread, plcomwrite, plcomioctl,
197 	plcomstop, plcomtty, plcompoll, nommap, ttykqfilter, D_TTY
198 };
199 
200 /*
201  * Make this an option variable one can patch.
202  * But be warned:  this must be a power of 2!
203  */
204 u_int plcom_rbuf_size = PLCOM_RING_SIZE;
205 
206 /* Stop input when 3/4 of the ring is full; restart when only 1/4 is full. */
207 u_int plcom_rbuf_hiwat = (PLCOM_RING_SIZE * 1) / 4;
208 u_int plcom_rbuf_lowat = (PLCOM_RING_SIZE * 3) / 4;
209 
210 static int	plcomconsunit = -1;
211 static bus_space_tag_t plcomconstag;
212 static bus_space_handle_t plcomconsioh;
213 static int	plcomconsattached;
214 static int plcomconsrate;
215 static tcflag_t plcomconscflag;
216 static struct cnm_state plcom_cnm_state;
217 
218 static int ppscap =
219 	PPS_TSFMT_TSPEC |
220 	PPS_CAPTUREASSERT |
221 	PPS_CAPTURECLEAR |
222 #ifdef  PPS_SYNC
223 	PPS_HARDPPSONASSERT | PPS_HARDPPSONCLEAR |
224 #endif	/* PPS_SYNC */
225 	PPS_OFFSETASSERT | PPS_OFFSETCLEAR;
226 
227 #ifdef KGDB
228 #include <sys/kgdb.h>
229 
230 static int plcom_kgdb_unit;
231 static bus_space_tag_t plcom_kgdb_iot;
232 static bus_space_handle_t plcom_kgdb_ioh;
233 static int plcom_kgdb_attached;
234 
235 int	plcom_kgdb_getc (void *);
236 void	plcom_kgdb_putc (void *, int);
237 #endif /* KGDB */
238 
239 #define	PLCOMUNIT_MASK	0x7ffff
240 #define	PLCOMDIALOUT_MASK	0x80000
241 
242 #define	PLCOMUNIT(x)	(minor(x) & PLCOMUNIT_MASK)
243 #define	PLCOMDIALOUT(x)	(minor(x) & PLCOMDIALOUT_MASK)
244 
245 #define	PLCOM_ISALIVE(sc)	((sc)->enabled != 0 && \
246 				 device_is_active(&(sc)->sc_dev))
247 
248 #define	BR	BUS_SPACE_BARRIER_READ
249 #define	BW	BUS_SPACE_BARRIER_WRITE
250 #define PLCOM_BARRIER(t, h, f) bus_space_barrier((t), (h), 0, PLCOM_UART_SIZE, (f))
251 
252 #define PLCOM_LOCK(sc) simple_lock(&(sc)->sc_lock)
253 #define PLCOM_UNLOCK(sc) simple_unlock(&(sc)->sc_lock)
254 
255 int
256 plcomspeed(long speed, long frequency)
257 {
258 #define	divrnd(n, q)	(((n)*2/(q)+1)/2)	/* divide and round off */
259 
260 	int x, err;
261 
262 #if 0
263 	if (speed == 0)
264 		return 0;
265 #endif
266 	if (speed <= 0)
267 		return -1;
268 	x = divrnd(frequency / 16, speed);
269 	if (x <= 0)
270 		return -1;
271 	err = divrnd(((quad_t)frequency) * 1000 / 16, speed * x) - 1000;
272 	if (err < 0)
273 		err = -err;
274 	if (err > PLCOM_TOLERANCE)
275 		return -1;
276 	return x;
277 
278 #undef	divrnd
279 }
280 
281 #ifdef PLCOM_DEBUG
282 int	plcom_debug = 0;
283 
284 void plcomstatus (struct plcom_softc *, char *);
285 void
286 plcomstatus(struct plcom_softc *sc, char *str)
287 {
288 	struct tty *tp = sc->sc_tty;
289 
290 	printf("%s: %s %sclocal  %sdcd %sts_carr_on %sdtr %stx_stopped\n",
291 	    sc->sc_dev.dv_xname, str,
292 	    ISSET(tp->t_cflag, CLOCAL) ? "+" : "-",
293 	    ISSET(sc->sc_msr, MSR_DCD) ? "+" : "-",
294 	    ISSET(tp->t_state, TS_CARR_ON) ? "+" : "-",
295 	    ISSET(sc->sc_mcr, MCR_DTR) ? "+" : "-",
296 	    sc->sc_tx_stopped ? "+" : "-");
297 
298 	printf("%s: %s %scrtscts %scts %sts_ttstop  %srts %xrx_flags\n",
299 	    sc->sc_dev.dv_xname, str,
300 	    ISSET(tp->t_cflag, CRTSCTS) ? "+" : "-",
301 	    ISSET(sc->sc_msr, MSR_CTS) ? "+" : "-",
302 	    ISSET(tp->t_state, TS_TTSTOP) ? "+" : "-",
303 	    ISSET(sc->sc_mcr, MCR_RTS) ? "+" : "-",
304 	    sc->sc_rx_flags);
305 }
306 #endif
307 
308 int
309 plcomprobe1(bus_space_tag_t iot, bus_space_handle_t ioh)
310 {
311 	int data;
312 
313 	/* Disable the UART.  */
314 	bus_space_write_1(iot, ioh, plcom_cr, 0);
315 	/* Make sure the FIFO is off.  */
316 	bus_space_write_1(iot, ioh, plcom_lcr, LCR_8BITS);
317 	/* Disable interrupts.  */
318 	bus_space_write_1(iot, ioh, plcom_iir, 0);
319 
320 	/* Make sure we swallow anything in the receiving register.  */
321 	data = bus_space_read_1(iot, ioh, plcom_dr);
322 
323 	if (bus_space_read_1(iot, ioh, plcom_lcr) != LCR_8BITS)
324 		return 0;
325 
326 	data = bus_space_read_1(iot, ioh, plcom_fr) & (FR_RXFF | FR_RXFE);
327 
328 	if (data != FR_RXFE)
329 		return 0;
330 
331 	return 1;
332 }
333 
334 static void
335 plcom_enable_debugport(struct plcom_softc *sc)
336 {
337 	int s;
338 
339 	/* Turn on line break interrupt, set carrier. */
340 	s = splserial();
341 	PLCOM_LOCK(sc);
342 	sc->sc_cr = CR_RIE | CR_RTIE | CR_UARTEN;
343 	bus_space_write_1(sc->sc_iot, sc->sc_ioh, plcom_cr, sc->sc_cr);
344 	SET(sc->sc_mcr, MCR_DTR | MCR_RTS);
345 	/* XXX device_unit() abuse */
346 	sc->sc_set_mcr(sc->sc_set_mcr_arg, device_unit(&sc->sc_dev),
347 	    sc->sc_mcr);
348 	PLCOM_UNLOCK(sc);
349 	splx(s);
350 }
351 
352 void
353 plcom_attach_subr(struct plcom_softc *sc)
354 {
355 	int unit = sc->sc_iounit;
356 	bus_space_tag_t iot = sc->sc_iot;
357 	bus_space_handle_t ioh = sc->sc_ioh;
358 	struct tty *tp;
359 
360 	callout_init(&sc->sc_diag_callout, 0);
361 	simple_lock_init(&sc->sc_lock);
362 
363 	/* Disable interrupts before configuring the device. */
364 	sc->sc_cr = 0;
365 
366 	if (plcomconstag && unit == plcomconsunit) {
367 		plcomconsattached = 1;
368 
369 		plcomconstag = iot;
370 		plcomconsioh = ioh;
371 
372 		/* Make sure the console is always "hardwired". */
373 		delay(1000);			/* wait for output to finish */
374 		SET(sc->sc_hwflags, PLCOM_HW_CONSOLE);
375 		SET(sc->sc_swflags, TIOCFLAG_SOFTCAR);
376 		/* Must re-enable the console immediately, or we will
377 		   hang when trying to print.  */
378 		sc->sc_cr = CR_UARTEN;
379 	}
380 
381 	bus_space_write_1(iot, ioh, plcom_cr, sc->sc_cr);
382 
383 	/* The PL010 has a 16-byte fifo, but the tx interrupt triggers when
384 	   there is space for 8 more bytes.  */
385 	sc->sc_fifolen = 8;
386 	printf("\n");
387 
388 	if (ISSET(sc->sc_hwflags, PLCOM_HW_TXFIFO_DISABLE)) {
389 		sc->sc_fifolen = 1;
390 		printf("%s: txfifo disabled\n", sc->sc_dev.dv_xname);
391 	}
392 
393 	if (sc->sc_fifolen > 1)
394 		SET(sc->sc_hwflags, PLCOM_HW_FIFO);
395 
396 	tp = ttymalloc();
397 	tp->t_oproc = plcomstart;
398 	tp->t_param = plcomparam;
399 	tp->t_hwiflow = plcomhwiflow;
400 
401 	sc->sc_tty = tp;
402 	sc->sc_rbuf = malloc(plcom_rbuf_size << 1, M_DEVBUF, M_NOWAIT);
403 	sc->sc_rbput = sc->sc_rbget = sc->sc_rbuf;
404 	sc->sc_rbavail = plcom_rbuf_size;
405 	if (sc->sc_rbuf == NULL) {
406 		printf("%s: unable to allocate ring buffer\n",
407 		    sc->sc_dev.dv_xname);
408 		return;
409 	}
410 	sc->sc_ebuf = sc->sc_rbuf + (plcom_rbuf_size << 1);
411 
412 	tty_attach(tp);
413 
414 	if (ISSET(sc->sc_hwflags, PLCOM_HW_CONSOLE)) {
415 		int maj;
416 
417 		/* locate the major number */
418 		maj = cdevsw_lookup_major(&plcom_cdevsw);
419 
420 		cn_tab->cn_dev = makedev(maj, device_unit(&sc->sc_dev));
421 
422 		printf("%s: console\n", sc->sc_dev.dv_xname);
423 	}
424 
425 #ifdef KGDB
426 	/*
427 	 * Allow kgdb to "take over" this port.  If this is
428 	 * the kgdb device, it has exclusive use.
429 	 */
430 	if (iot == plcom_kgdb_iot && unit == plcom_kgdb_unit) {
431 		plcom_kgdb_attached = 1;
432 
433 		SET(sc->sc_hwflags, PLCOM_HW_KGDB);
434 		printf("%s: kgdb\n", sc->sc_dev.dv_xname);
435 	}
436 #endif
437 
438 	sc->sc_si = softint_establish(SOFTINT_SERIAL, plcomsoft, sc);
439 
440 #if NRND > 0 && defined(RND_COM)
441 	rnd_attach_source(&sc->rnd_source, sc->sc_dev.dv_xname,
442 			  RND_TYPE_TTY, 0);
443 #endif
444 
445 	/* if there are no enable/disable functions, assume the device
446 	   is always enabled */
447 	if (!sc->enable)
448 		sc->enabled = 1;
449 
450 	plcom_config(sc);
451 
452 	SET(sc->sc_hwflags, PLCOM_HW_DEV_OK);
453 }
454 
455 void
456 plcom_config(struct plcom_softc *sc)
457 {
458 	bus_space_tag_t iot = sc->sc_iot;
459 	bus_space_handle_t ioh = sc->sc_ioh;
460 
461 	/* Disable interrupts before configuring the device. */
462 	sc->sc_cr = 0;
463 	bus_space_write_1(iot, ioh, plcom_cr, sc->sc_cr);
464 
465 	if (ISSET(sc->sc_hwflags, PLCOM_HW_CONSOLE|PLCOM_HW_KGDB))
466 		plcom_enable_debugport(sc);
467 }
468 
469 int
470 plcom_detach(struct device *self, int flags)
471 {
472 	struct plcom_softc *sc = (struct plcom_softc *)self;
473 	int maj, mn;
474 
475 	/* locate the major number */
476 	maj = cdevsw_lookup_major(&plcom_cdevsw);
477 
478 	/* Nuke the vnodes for any open instances. */
479 	mn = device_unit(self);
480 	vdevgone(maj, mn, mn, VCHR);
481 
482 	mn |= PLCOMDIALOUT_MASK;
483 	vdevgone(maj, mn, mn, VCHR);
484 
485 	/* Free the receive buffer. */
486 	free(sc->sc_rbuf, M_DEVBUF);
487 
488 	/* Detach and free the tty. */
489 	tty_detach(sc->sc_tty);
490 	ttyfree(sc->sc_tty);
491 
492 	/* Unhook the soft interrupt handler. */
493 	softint_disestablish(sc->sc_si);
494 
495 #if NRND > 0 && defined(RND_COM)
496 	/* Unhook the entropy source. */
497 	rnd_detach_source(&sc->rnd_source);
498 #endif
499 
500 	return 0;
501 }
502 
503 int
504 plcom_activate(struct device *self, enum devact act)
505 {
506 	struct plcom_softc *sc = (struct plcom_softc *)self;
507 	int s, rv = 0;
508 
509 	s = splserial();
510 	PLCOM_LOCK(sc);
511 	switch (act) {
512 	case DVACT_ACTIVATE:
513 		rv = EOPNOTSUPP;
514 		break;
515 
516 	case DVACT_DEACTIVATE:
517 		if (sc->sc_hwflags & (PLCOM_HW_CONSOLE|PLCOM_HW_KGDB)) {
518 			rv = EBUSY;
519 			break;
520 		}
521 
522 		if (sc->disable != NULL && sc->enabled != 0) {
523 			(*sc->disable)(sc);
524 			sc->enabled = 0;
525 		}
526 		break;
527 	}
528 
529 	PLCOM_UNLOCK(sc);
530 	splx(s);
531 	return rv;
532 }
533 
534 void
535 plcom_shutdown(struct plcom_softc *sc)
536 {
537 	struct tty *tp = sc->sc_tty;
538 	int s;
539 
540 	s = splserial();
541 	PLCOM_LOCK(sc);
542 
543 	/* If we were asserting flow control, then deassert it. */
544 	SET(sc->sc_rx_flags, RX_IBUF_BLOCKED);
545 	plcom_hwiflow(sc);
546 
547 	/* Clear any break condition set with TIOCSBRK. */
548 	plcom_break(sc, 0);
549 
550 	/* Turn off PPS capture on last close. */
551 	mutex_spin_enter(&timecounter_lock);
552 	sc->sc_ppsmask = 0;
553 	sc->ppsparam.mode = 0;
554 	mutex_spin_exit(&timecounter_lock);
555 
556 	/*
557 	 * Hang up if necessary.  Wait a bit, so the other side has time to
558 	 * notice even if we immediately open the port again.
559 	 * Avoid tsleeping above splhigh().
560 	 */
561 	if (ISSET(tp->t_cflag, HUPCL)) {
562 		plcom_modem(sc, 0);
563 		PLCOM_UNLOCK(sc);
564 		splx(s);
565 		/* XXX tsleep will only timeout */
566 		(void) tsleep(sc, TTIPRI, ttclos, hz);
567 		s = splserial();
568 		PLCOM_LOCK(sc);
569 	}
570 
571 	/* Turn off interrupts. */
572 	if (ISSET(sc->sc_hwflags, PLCOM_HW_CONSOLE))
573 		/* interrupt on break */
574 		sc->sc_cr = CR_RIE | CR_RTIE | CR_UARTEN;
575 	else
576 		sc->sc_cr = 0;
577 	bus_space_write_1(sc->sc_iot, sc->sc_ioh, plcom_cr, sc->sc_cr);
578 
579 	if (sc->disable) {
580 #ifdef DIAGNOSTIC
581 		if (!sc->enabled)
582 			panic("plcom_shutdown: not enabled?");
583 #endif
584 		(*sc->disable)(sc);
585 		sc->enabled = 0;
586 	}
587 	PLCOM_UNLOCK(sc);
588 	splx(s);
589 }
590 
591 int
592 plcomopen(dev_t dev, int flag, int mode, struct lwp *l)
593 {
594 	struct plcom_softc *sc;
595 	struct tty *tp;
596 	int s, s2;
597 	int error;
598 
599 	sc = device_lookup_private(&plcom_cd, PLCOMUNIT(dev));
600 	if (sc == NULL || !ISSET(sc->sc_hwflags, PLCOM_HW_DEV_OK) ||
601 		sc->sc_rbuf == NULL)
602 		return ENXIO;
603 
604 	if (!device_is_active(&sc->sc_dev))
605 		return ENXIO;
606 
607 #ifdef KGDB
608 	/*
609 	 * If this is the kgdb port, no other use is permitted.
610 	 */
611 	if (ISSET(sc->sc_hwflags, PLCOM_HW_KGDB))
612 		return EBUSY;
613 #endif
614 
615 	tp = sc->sc_tty;
616 
617 	if (kauth_authorize_device_tty(l->l_cred, KAUTH_DEVICE_TTY_OPEN, tp))
618 		return (EBUSY);
619 
620 	s = spltty();
621 
622 	/*
623 	 * Do the following iff this is a first open.
624 	 */
625 	if (!ISSET(tp->t_state, TS_ISOPEN) && tp->t_wopen == 0) {
626 		struct termios t;
627 
628 		tp->t_dev = dev;
629 
630 		s2 = splserial();
631 		PLCOM_LOCK(sc);
632 
633 		if (sc->enable) {
634 			if ((*sc->enable)(sc)) {
635 				PLCOM_UNLOCK(sc);
636 				splx(s2);
637 				splx(s);
638 				printf("%s: device enable failed\n",
639 				       sc->sc_dev.dv_xname);
640 				return EIO;
641 			}
642 			sc->enabled = 1;
643 			plcom_config(sc);
644 		}
645 
646 		/* Turn on interrupts. */
647 		/* IER_ERXRDY | IER_ERLS | IER_EMSC;  */
648 		sc->sc_cr = CR_RIE | CR_RTIE | CR_MSIE | CR_UARTEN;
649 		bus_space_write_1(sc->sc_iot, sc->sc_ioh, plcom_cr, sc->sc_cr);
650 
651 		/* Fetch the current modem control status, needed later. */
652 		sc->sc_msr = bus_space_read_1(sc->sc_iot, sc->sc_ioh, plcom_fr);
653 
654 		/* Clear PPS capture state on first open. */
655 
656 		mutex_spin_enter(&timecounter_lock);
657 		sc->sc_ppsmask = 0;
658 		sc->ppsparam.mode = 0;
659 		mutex_spin_exit(&timecounter_lock);
660 
661 		PLCOM_UNLOCK(sc);
662 		splx(s2);
663 
664 		/*
665 		 * Initialize the termios status to the defaults.  Add in the
666 		 * sticky bits from TIOCSFLAGS.
667 		 */
668 		t.c_ispeed = 0;
669 		if (ISSET(sc->sc_hwflags, PLCOM_HW_CONSOLE)) {
670 			t.c_ospeed = plcomconsrate;
671 			t.c_cflag = plcomconscflag;
672 		} else {
673 			t.c_ospeed = TTYDEF_SPEED;
674 			t.c_cflag = TTYDEF_CFLAG;
675 		}
676 		if (ISSET(sc->sc_swflags, TIOCFLAG_CLOCAL))
677 			SET(t.c_cflag, CLOCAL);
678 		if (ISSET(sc->sc_swflags, TIOCFLAG_CRTSCTS))
679 			SET(t.c_cflag, CRTSCTS);
680 		if (ISSET(sc->sc_swflags, TIOCFLAG_MDMBUF))
681 			SET(t.c_cflag, MDMBUF);
682 		/* Make sure plcomparam() will do something. */
683 		tp->t_ospeed = 0;
684 		(void) plcomparam(tp, &t);
685 		tp->t_iflag = TTYDEF_IFLAG;
686 		tp->t_oflag = TTYDEF_OFLAG;
687 		tp->t_lflag = TTYDEF_LFLAG;
688 		ttychars(tp);
689 		ttsetwater(tp);
690 
691 		s2 = splserial();
692 		PLCOM_LOCK(sc);
693 
694 		/*
695 		 * Turn on DTR.  We must always do this, even if carrier is not
696 		 * present, because otherwise we'd have to use TIOCSDTR
697 		 * immediately after setting CLOCAL, which applications do not
698 		 * expect.  We always assert DTR while the device is open
699 		 * unless explicitly requested to deassert it.
700 		 */
701 		plcom_modem(sc, 1);
702 
703 		/* Clear the input ring, and unblock. */
704 		sc->sc_rbput = sc->sc_rbget = sc->sc_rbuf;
705 		sc->sc_rbavail = plcom_rbuf_size;
706 		plcom_iflush(sc);
707 		CLR(sc->sc_rx_flags, RX_ANY_BLOCK);
708 		plcom_hwiflow(sc);
709 
710 #ifdef PLCOM_DEBUG
711 		if (plcom_debug)
712 			plcomstatus(sc, "plcomopen  ");
713 #endif
714 
715 		PLCOM_UNLOCK(sc);
716 		splx(s2);
717 	}
718 
719 	splx(s);
720 
721 	error = ttyopen(tp, PLCOMDIALOUT(dev), ISSET(flag, O_NONBLOCK));
722 	if (error)
723 		goto bad;
724 
725 	error = (*tp->t_linesw->l_open)(dev, tp);
726 	if (error)
727 		goto bad;
728 
729 	return 0;
730 
731 bad:
732 	if (!ISSET(tp->t_state, TS_ISOPEN) && tp->t_wopen == 0) {
733 		/*
734 		 * We failed to open the device, and nobody else had it opened.
735 		 * Clean up the state as appropriate.
736 		 */
737 		plcom_shutdown(sc);
738 	}
739 
740 	return error;
741 }
742 
743 int
744 plcomclose(dev_t dev, int flag, int mode, struct lwp *l)
745 {
746 	struct plcom_softc *sc =
747 		device_lookup_private(&plcom_cd, PLCOMUNIT(dev));
748 	struct tty *tp = sc->sc_tty;
749 
750 	/* XXX This is for cons.c. */
751 	if (!ISSET(tp->t_state, TS_ISOPEN))
752 		return 0;
753 
754 	(*tp->t_linesw->l_close)(tp, flag);
755 	ttyclose(tp);
756 
757 	if (PLCOM_ISALIVE(sc) == 0)
758 		return 0;
759 
760 	if (!ISSET(tp->t_state, TS_ISOPEN) && tp->t_wopen == 0) {
761 		/*
762 		 * Although we got a last close, the device may still be in
763 		 * use; e.g. if this was the dialout node, and there are still
764 		 * processes waiting for carrier on the non-dialout node.
765 		 */
766 		plcom_shutdown(sc);
767 	}
768 
769 	return 0;
770 }
771 
772 int
773 plcomread(dev_t dev, struct uio *uio, int flag)
774 {
775 	struct plcom_softc *sc =
776 		device_lookup_private(&plcom_cd, PLCOMUNIT(dev));
777 	struct tty *tp = sc->sc_tty;
778 
779 	if (PLCOM_ISALIVE(sc) == 0)
780 		return EIO;
781 
782 	return (*tp->t_linesw->l_read)(tp, uio, flag);
783 }
784 
785 int
786 plcomwrite(dev_t dev, struct uio *uio, int flag)
787 {
788 	struct plcom_softc *sc =
789 		device_lookup_private(&plcom_cd, PLCOMUNIT(dev));
790 	struct tty *tp = sc->sc_tty;
791 
792 	if (PLCOM_ISALIVE(sc) == 0)
793 		return EIO;
794 
795 	return (*tp->t_linesw->l_write)(tp, uio, flag);
796 }
797 
798 int
799 plcompoll(dev_t dev, int events, struct lwp *l)
800 {
801 	struct plcom_softc *sc =
802 		device_lookup_private(&plcom_cd, PLCOMUNIT(dev));
803 	struct tty *tp = sc->sc_tty;
804 
805 	if (PLCOM_ISALIVE(sc) == 0)
806 		return EIO;
807 
808 	return (*tp->t_linesw->l_poll)(tp, events, l);
809 }
810 
811 struct tty *
812 plcomtty(dev_t dev)
813 {
814 	struct plcom_softc *sc =
815 		device_lookup_private(&plcom_cd, PLCOMUNIT(dev));
816 	struct tty *tp = sc->sc_tty;
817 
818 	return tp;
819 }
820 
821 int
822 plcomioctl(dev_t dev, u_long cmd, void *data, int flag, struct lwp *l)
823 {
824 	struct plcom_softc *sc =
825 		device_lookup_private(&plcom_cd, PLCOMUNIT(dev));
826 	struct tty *tp = sc->sc_tty;
827 	int error;
828 	int s;
829 
830 	if (PLCOM_ISALIVE(sc) == 0)
831 		return EIO;
832 
833 	error = (*tp->t_linesw->l_ioctl)(tp, cmd, data, flag, l);
834 	if (error != EPASSTHROUGH)
835 		return error;
836 
837 	error = ttioctl(tp, cmd, data, flag, l);
838 	if (error != EPASSTHROUGH)
839 		return error;
840 
841 	error = 0;
842 
843 	s = splserial();
844 	PLCOM_LOCK(sc);
845 
846 	switch (cmd) {
847 	case TIOCSBRK:
848 		plcom_break(sc, 1);
849 		break;
850 
851 	case TIOCCBRK:
852 		plcom_break(sc, 0);
853 		break;
854 
855 	case TIOCSDTR:
856 		plcom_modem(sc, 1);
857 		break;
858 
859 	case TIOCCDTR:
860 		plcom_modem(sc, 0);
861 		break;
862 
863 	case TIOCGFLAGS:
864 		*(int *)data = sc->sc_swflags;
865 		break;
866 
867 	case TIOCSFLAGS:
868 		error = kauth_authorize_device_tty(l->l_cred,
869 		    KAUTH_DEVICE_TTY_PRIVSET, tp);
870 		if (error)
871 			break;
872 		sc->sc_swflags = *(int *)data;
873 		break;
874 
875 	case TIOCMSET:
876 	case TIOCMBIS:
877 	case TIOCMBIC:
878 		tiocm_to_plcom(sc, cmd, *(int *)data);
879 		break;
880 
881 	case TIOCMGET:
882 		*(int *)data = plcom_to_tiocm(sc);
883 		break;
884 
885 	case PPS_IOC_CREATE:
886 		break;
887 
888 	case PPS_IOC_DESTROY:
889 		break;
890 
891 	case PPS_IOC_GETPARAMS: {
892 		pps_params_t *pp;
893 		pp = (pps_params_t *)data;
894 		mutex_spin_enter(&timecounter_lock);
895 		*pp = sc->ppsparam;
896 		mutex_spin_exit(&timecounter_lock);
897 		break;
898 	}
899 
900 	case PPS_IOC_SETPARAMS: {
901 	  	pps_params_t *pp;
902 		int mode;
903 		pp = (pps_params_t *)data;
904 		mutex_spin_enter(&timecounter_lock);
905 		if (pp->mode & ~ppscap) {
906 			error = EINVAL;
907 			mutex_spin_exit(&timecounter_lock);
908 			break;
909 		}
910 		sc->ppsparam = *pp;
911 	 	/*
912 		 * Compute msr masks from user-specified timestamp state.
913 		 */
914 		mode = sc->ppsparam.mode;
915 #ifdef	PPS_SYNC
916 		if (mode & PPS_HARDPPSONASSERT) {
917 			mode |= PPS_CAPTUREASSERT;
918 			/* XXX revoke any previous HARDPPS source */
919 		}
920 		if (mode & PPS_HARDPPSONCLEAR) {
921 			mode |= PPS_CAPTURECLEAR;
922 			/* XXX revoke any previous HARDPPS source */
923 		}
924 #endif	/* PPS_SYNC */
925 		switch (mode & PPS_CAPTUREBOTH) {
926 		case 0:
927 			sc->sc_ppsmask = 0;
928 			break;
929 
930 		case PPS_CAPTUREASSERT:
931 			sc->sc_ppsmask = MSR_DCD;
932 			sc->sc_ppsassert = MSR_DCD;
933 			sc->sc_ppsclear = -1;
934 			break;
935 
936 		case PPS_CAPTURECLEAR:
937 			sc->sc_ppsmask = MSR_DCD;
938 			sc->sc_ppsassert = -1;
939 			sc->sc_ppsclear = 0;
940 			break;
941 
942 		case PPS_CAPTUREBOTH:
943 			sc->sc_ppsmask = MSR_DCD;
944 			sc->sc_ppsassert = MSR_DCD;
945 			sc->sc_ppsclear = 0;
946 			break;
947 
948 		default:
949 			error = EINVAL;
950 			break;
951 		}
952 		mutex_spin_exit(&timecounter_lock);
953 		break;
954 	}
955 
956 	case PPS_IOC_GETCAP:
957 		*(int*)data = ppscap;
958 		break;
959 
960 	case PPS_IOC_FETCH: {
961 		pps_info_t *pi;
962 		pi = (pps_info_t *)data;
963 		mutex_spin_enter(&timecounter_lock);
964 		*pi = sc->ppsinfo;
965 		mutex_spin_exit(&timecounter_lock);
966 		break;
967 	}
968 
969 	case TIOCDCDTIMESTAMP:	/* XXX old, overloaded  API used by xntpd v3 */
970 		/*
971 		 * Some GPS clocks models use the falling rather than
972 		 * rising edge as the on-the-second signal.
973 		 * The old API has no way to specify PPS polarity.
974 		 */
975 		mutex_spin_enter(&timecounter_lock);
976 		sc->sc_ppsmask = MSR_DCD;
977 #ifndef PPS_TRAILING_EDGE
978 		sc->sc_ppsassert = MSR_DCD;
979 		sc->sc_ppsclear = -1;
980 		TIMESPEC_TO_TIMEVAL((struct timeval *)data,
981 		    &sc->ppsinfo.assert_timestamp);
982 #else
983 		sc->sc_ppsassert = -1
984 		sc->sc_ppsclear = 0;
985 		TIMESPEC_TO_TIMEVAL((struct timeval *)data,
986 		    &sc->ppsinfo.clear_timestamp);
987 #endif
988 		mutex_spin_exit(&timecounter_lock);
989 		break;
990 
991 	default:
992 		error = EPASSTHROUGH;
993 		break;
994 	}
995 
996 	PLCOM_UNLOCK(sc);
997 	splx(s);
998 
999 #ifdef PLCOM_DEBUG
1000 	if (plcom_debug)
1001 		plcomstatus(sc, "plcomioctl ");
1002 #endif
1003 
1004 	return error;
1005 }
1006 
1007 integrate void
1008 plcom_schedrx(struct plcom_softc *sc)
1009 {
1010 
1011 	sc->sc_rx_ready = 1;
1012 
1013 	/* Wake up the poller. */
1014 	softint_schedule(sc->sc_si);
1015 }
1016 
1017 void
1018 plcom_break(struct plcom_softc *sc, int onoff)
1019 {
1020 
1021 	if (onoff)
1022 		SET(sc->sc_lcr, LCR_BRK);
1023 	else
1024 		CLR(sc->sc_lcr, LCR_BRK);
1025 
1026 	if (!sc->sc_heldchange) {
1027 		if (sc->sc_tx_busy) {
1028 			sc->sc_heldtbc = sc->sc_tbc;
1029 			sc->sc_tbc = 0;
1030 			sc->sc_heldchange = 1;
1031 		} else
1032 			plcom_loadchannelregs(sc);
1033 	}
1034 }
1035 
1036 void
1037 plcom_modem(struct plcom_softc *sc, int onoff)
1038 {
1039 
1040 	if (sc->sc_mcr_dtr == 0)
1041 		return;
1042 
1043 	if (onoff)
1044 		SET(sc->sc_mcr, sc->sc_mcr_dtr);
1045 	else
1046 		CLR(sc->sc_mcr, sc->sc_mcr_dtr);
1047 
1048 	if (!sc->sc_heldchange) {
1049 		if (sc->sc_tx_busy) {
1050 			sc->sc_heldtbc = sc->sc_tbc;
1051 			sc->sc_tbc = 0;
1052 			sc->sc_heldchange = 1;
1053 		} else
1054 			plcom_loadchannelregs(sc);
1055 	}
1056 }
1057 
1058 void
1059 tiocm_to_plcom(struct plcom_softc *sc, u_long how, int ttybits)
1060 {
1061 	u_char plcombits;
1062 
1063 	plcombits = 0;
1064 	if (ISSET(ttybits, TIOCM_DTR))
1065 		SET(plcombits, MCR_DTR);
1066 	if (ISSET(ttybits, TIOCM_RTS))
1067 		SET(plcombits, MCR_RTS);
1068 
1069 	switch (how) {
1070 	case TIOCMBIC:
1071 		CLR(sc->sc_mcr, plcombits);
1072 		break;
1073 
1074 	case TIOCMBIS:
1075 		SET(sc->sc_mcr, plcombits);
1076 		break;
1077 
1078 	case TIOCMSET:
1079 		CLR(sc->sc_mcr, MCR_DTR | MCR_RTS);
1080 		SET(sc->sc_mcr, plcombits);
1081 		break;
1082 	}
1083 
1084 	if (!sc->sc_heldchange) {
1085 		if (sc->sc_tx_busy) {
1086 			sc->sc_heldtbc = sc->sc_tbc;
1087 			sc->sc_tbc = 0;
1088 			sc->sc_heldchange = 1;
1089 		} else
1090 			plcom_loadchannelregs(sc);
1091 	}
1092 }
1093 
1094 int
1095 plcom_to_tiocm(struct plcom_softc *sc)
1096 {
1097 	u_char plcombits;
1098 	int ttybits = 0;
1099 
1100 	plcombits = sc->sc_mcr;
1101 	if (ISSET(plcombits, MCR_DTR))
1102 		SET(ttybits, TIOCM_DTR);
1103 	if (ISSET(plcombits, MCR_RTS))
1104 		SET(ttybits, TIOCM_RTS);
1105 
1106 	plcombits = sc->sc_msr;
1107 	if (ISSET(plcombits, MSR_DCD))
1108 		SET(ttybits, TIOCM_CD);
1109 	if (ISSET(plcombits, MSR_CTS))
1110 		SET(ttybits, TIOCM_CTS);
1111 	if (ISSET(plcombits, MSR_DSR))
1112 		SET(ttybits, TIOCM_DSR);
1113 
1114 	if (sc->sc_cr != 0)
1115 		SET(ttybits, TIOCM_LE);
1116 
1117 	return ttybits;
1118 }
1119 
1120 static u_char
1121 cflag2lcr(tcflag_t cflag)
1122 {
1123 	u_char lcr = 0;
1124 
1125 	switch (ISSET(cflag, CSIZE)) {
1126 	case CS5:
1127 		SET(lcr, LCR_5BITS);
1128 		break;
1129 	case CS6:
1130 		SET(lcr, LCR_6BITS);
1131 		break;
1132 	case CS7:
1133 		SET(lcr, LCR_7BITS);
1134 		break;
1135 	case CS8:
1136 		SET(lcr, LCR_8BITS);
1137 		break;
1138 	}
1139 	if (ISSET(cflag, PARENB)) {
1140 		SET(lcr, LCR_PEN);
1141 		if (!ISSET(cflag, PARODD))
1142 			SET(lcr, LCR_EPS);
1143 	}
1144 	if (ISSET(cflag, CSTOPB))
1145 		SET(lcr, LCR_STP2);
1146 
1147 	return lcr;
1148 }
1149 
1150 int
1151 plcomparam(struct tty *tp, struct termios *t)
1152 {
1153 	struct plcom_softc *sc =
1154 		device_lookup_private(&plcom_cd, PLCOMUNIT(tp->t_dev));
1155 	int ospeed;
1156 	u_char lcr;
1157 	int s;
1158 
1159 	if (PLCOM_ISALIVE(sc) == 0)
1160 		return EIO;
1161 
1162 	ospeed = plcomspeed(t->c_ospeed, sc->sc_frequency);
1163 
1164 	/* Check requested parameters. */
1165 	if (ospeed < 0)
1166 		return EINVAL;
1167 	if (t->c_ispeed && t->c_ispeed != t->c_ospeed)
1168 		return EINVAL;
1169 
1170 	/*
1171 	 * For the console, always force CLOCAL and !HUPCL, so that the port
1172 	 * is always active.
1173 	 */
1174 	if (ISSET(sc->sc_swflags, TIOCFLAG_SOFTCAR) ||
1175 	    ISSET(sc->sc_hwflags, PLCOM_HW_CONSOLE)) {
1176 		SET(t->c_cflag, CLOCAL);
1177 		CLR(t->c_cflag, HUPCL);
1178 	}
1179 
1180 	/*
1181 	 * If there were no changes, don't do anything.  This avoids dropping
1182 	 * input and improves performance when all we did was frob things like
1183 	 * VMIN and VTIME.
1184 	 */
1185 	if (tp->t_ospeed == t->c_ospeed &&
1186 	    tp->t_cflag == t->c_cflag)
1187 		return 0;
1188 
1189 	lcr = ISSET(sc->sc_lcr, LCR_BRK) | cflag2lcr(t->c_cflag);
1190 
1191 	s = splserial();
1192 	PLCOM_LOCK(sc);
1193 
1194 	sc->sc_lcr = lcr;
1195 
1196 	/*
1197 	 * PL010 has a fixed-length FIFO trigger point.
1198 	 */
1199 	if (ISSET(sc->sc_hwflags, PLCOM_HW_FIFO))
1200 		sc->sc_fifo = 1;
1201 	else
1202 		sc->sc_fifo = 0;
1203 
1204 	if (sc->sc_fifo)
1205 		SET(sc->sc_lcr, LCR_FEN);
1206 
1207 	/*
1208 	 * If we're not in a mode that assumes a connection is present, then
1209 	 * ignore carrier changes.
1210 	 */
1211 	if (ISSET(t->c_cflag, CLOCAL | MDMBUF))
1212 		sc->sc_msr_dcd = 0;
1213 	else
1214 		sc->sc_msr_dcd = MSR_DCD;
1215 	/*
1216 	 * Set the flow control pins depending on the current flow control
1217 	 * mode.
1218 	 */
1219 	if (ISSET(t->c_cflag, CRTSCTS)) {
1220 		sc->sc_mcr_dtr = MCR_DTR;
1221 		sc->sc_mcr_rts = MCR_RTS;
1222 		sc->sc_msr_cts = MSR_CTS;
1223 	} else if (ISSET(t->c_cflag, MDMBUF)) {
1224 		/*
1225 		 * For DTR/DCD flow control, make sure we don't toggle DTR for
1226 		 * carrier detection.
1227 		 */
1228 		sc->sc_mcr_dtr = 0;
1229 		sc->sc_mcr_rts = MCR_DTR;
1230 		sc->sc_msr_cts = MSR_DCD;
1231 	} else {
1232 		/*
1233 		 * If no flow control, then always set RTS.  This will make
1234 		 * the other side happy if it mistakenly thinks we're doing
1235 		 * RTS/CTS flow control.
1236 		 */
1237 		sc->sc_mcr_dtr = MCR_DTR | MCR_RTS;
1238 		sc->sc_mcr_rts = 0;
1239 		sc->sc_msr_cts = 0;
1240 		if (ISSET(sc->sc_mcr, MCR_DTR))
1241 			SET(sc->sc_mcr, MCR_RTS);
1242 		else
1243 			CLR(sc->sc_mcr, MCR_RTS);
1244 	}
1245 	sc->sc_msr_mask = sc->sc_msr_cts | sc->sc_msr_dcd;
1246 
1247 #if 0
1248 	if (ospeed == 0)
1249 		CLR(sc->sc_mcr, sc->sc_mcr_dtr);
1250 	else
1251 		SET(sc->sc_mcr, sc->sc_mcr_dtr);
1252 #endif
1253 
1254 	sc->sc_dlbl = ospeed;
1255 	sc->sc_dlbh = ospeed >> 8;
1256 
1257 	/* And copy to tty. */
1258 	tp->t_ispeed = 0;
1259 	tp->t_ospeed = t->c_ospeed;
1260 	tp->t_cflag = t->c_cflag;
1261 
1262 	if (!sc->sc_heldchange) {
1263 		if (sc->sc_tx_busy) {
1264 			sc->sc_heldtbc = sc->sc_tbc;
1265 			sc->sc_tbc = 0;
1266 			sc->sc_heldchange = 1;
1267 		} else
1268 			plcom_loadchannelregs(sc);
1269 	}
1270 
1271 	if (!ISSET(t->c_cflag, CHWFLOW)) {
1272 		/* Disable the high water mark. */
1273 		sc->sc_r_hiwat = 0;
1274 		sc->sc_r_lowat = 0;
1275 		if (ISSET(sc->sc_rx_flags, RX_TTY_OVERFLOWED)) {
1276 			CLR(sc->sc_rx_flags, RX_TTY_OVERFLOWED);
1277 			plcom_schedrx(sc);
1278 		}
1279 		if (ISSET(sc->sc_rx_flags, RX_TTY_BLOCKED|RX_IBUF_BLOCKED)) {
1280 			CLR(sc->sc_rx_flags, RX_TTY_BLOCKED|RX_IBUF_BLOCKED);
1281 			plcom_hwiflow(sc);
1282 		}
1283 	} else {
1284 		sc->sc_r_hiwat = plcom_rbuf_hiwat;
1285 		sc->sc_r_lowat = plcom_rbuf_lowat;
1286 	}
1287 
1288 	PLCOM_UNLOCK(sc);
1289 	splx(s);
1290 
1291 	/*
1292 	 * Update the tty layer's idea of the carrier bit, in case we changed
1293 	 * CLOCAL or MDMBUF.  We don't hang up here; we only do that by
1294 	 * explicit request.
1295 	 */
1296 	(void) (*tp->t_linesw->l_modem)(tp, ISSET(sc->sc_msr, MSR_DCD));
1297 
1298 #ifdef PLCOM_DEBUG
1299 	if (plcom_debug)
1300 		plcomstatus(sc, "plcomparam ");
1301 #endif
1302 
1303 	if (!ISSET(t->c_cflag, CHWFLOW)) {
1304 		if (sc->sc_tx_stopped) {
1305 			sc->sc_tx_stopped = 0;
1306 			plcomstart(tp);
1307 		}
1308 	}
1309 
1310 	return 0;
1311 }
1312 
1313 void
1314 plcom_iflush(struct plcom_softc *sc)
1315 {
1316 	bus_space_tag_t iot = sc->sc_iot;
1317 	bus_space_handle_t ioh = sc->sc_ioh;
1318 #ifdef DIAGNOSTIC
1319 	int reg;
1320 #endif
1321 	int timo;
1322 
1323 #ifdef DIAGNOSTIC
1324 	reg = 0xffff;
1325 #endif
1326 	timo = 50000;
1327 	/* flush any pending I/O */
1328 	while (! ISSET(bus_space_read_1(iot, ioh, plcom_fr), FR_RXFE)
1329 	    && --timo)
1330 #ifdef DIAGNOSTIC
1331 		reg =
1332 #else
1333 		    (void)
1334 #endif
1335 		    bus_space_read_1(iot, ioh, plcom_dr);
1336 #ifdef DIAGNOSTIC
1337 	if (!timo)
1338 		printf("%s: plcom_iflush timeout %02x\n", sc->sc_dev.dv_xname,
1339 		       reg);
1340 #endif
1341 }
1342 
1343 void
1344 plcom_loadchannelregs(struct plcom_softc *sc)
1345 {
1346 	bus_space_tag_t iot = sc->sc_iot;
1347 	bus_space_handle_t ioh = sc->sc_ioh;
1348 
1349 	/* XXXXX necessary? */
1350 	plcom_iflush(sc);
1351 
1352 	bus_space_write_1(iot, ioh, plcom_cr, 0);
1353 
1354 	bus_space_write_1(iot, ioh, plcom_dlbl, sc->sc_dlbl);
1355 	bus_space_write_1(iot, ioh, plcom_dlbh, sc->sc_dlbh);
1356 	bus_space_write_1(iot, ioh, plcom_lcr, sc->sc_lcr);
1357 	/* XXX device_unit() abuse */
1358 	sc->sc_set_mcr(sc->sc_set_mcr_arg, device_unit(&sc->sc_dev),
1359 	    sc->sc_mcr_active = sc->sc_mcr);
1360 
1361 	bus_space_write_1(iot, ioh, plcom_cr, sc->sc_cr);
1362 }
1363 
1364 int
1365 plcomhwiflow(struct tty *tp, int block)
1366 {
1367 	struct plcom_softc *sc =
1368 		device_lookup_private(&plcom_cd, PLCOMUNIT(tp->t_dev));
1369 	int s;
1370 
1371 	if (PLCOM_ISALIVE(sc) == 0)
1372 		return 0;
1373 
1374 	if (sc->sc_mcr_rts == 0)
1375 		return 0;
1376 
1377 	s = splserial();
1378 	PLCOM_LOCK(sc);
1379 
1380 	if (block) {
1381 		if (!ISSET(sc->sc_rx_flags, RX_TTY_BLOCKED)) {
1382 			SET(sc->sc_rx_flags, RX_TTY_BLOCKED);
1383 			plcom_hwiflow(sc);
1384 		}
1385 	} else {
1386 		if (ISSET(sc->sc_rx_flags, RX_TTY_OVERFLOWED)) {
1387 			CLR(sc->sc_rx_flags, RX_TTY_OVERFLOWED);
1388 			plcom_schedrx(sc);
1389 		}
1390 		if (ISSET(sc->sc_rx_flags, RX_TTY_BLOCKED)) {
1391 			CLR(sc->sc_rx_flags, RX_TTY_BLOCKED);
1392 			plcom_hwiflow(sc);
1393 		}
1394 	}
1395 
1396 	PLCOM_UNLOCK(sc);
1397 	splx(s);
1398 	return 1;
1399 }
1400 
1401 /*
1402  * (un)block input via hw flowcontrol
1403  */
1404 void
1405 plcom_hwiflow(struct plcom_softc *sc)
1406 {
1407 	if (sc->sc_mcr_rts == 0)
1408 		return;
1409 
1410 	if (ISSET(sc->sc_rx_flags, RX_ANY_BLOCK)) {
1411 		CLR(sc->sc_mcr, sc->sc_mcr_rts);
1412 		CLR(sc->sc_mcr_active, sc->sc_mcr_rts);
1413 	} else {
1414 		SET(sc->sc_mcr, sc->sc_mcr_rts);
1415 		SET(sc->sc_mcr_active, sc->sc_mcr_rts);
1416 	}
1417 	/* XXX device_unit() abuse */
1418 	sc->sc_set_mcr(sc->sc_set_mcr_arg, device_unit(&sc->sc_dev),
1419 	    sc->sc_mcr_active);
1420 }
1421 
1422 
1423 void
1424 plcomstart(struct tty *tp)
1425 {
1426 	struct plcom_softc *sc =
1427 		device_lookup_private(&plcom_cd, PLCOMUNIT(tp->t_dev));
1428 	bus_space_tag_t iot = sc->sc_iot;
1429 	bus_space_handle_t ioh = sc->sc_ioh;
1430 	int s;
1431 
1432 	if (PLCOM_ISALIVE(sc) == 0)
1433 		return;
1434 
1435 	s = spltty();
1436 	if (ISSET(tp->t_state, TS_BUSY | TS_TIMEOUT | TS_TTSTOP))
1437 		goto out;
1438 	if (sc->sc_tx_stopped)
1439 		goto out;
1440 
1441 	if (!ttypull(tp))
1442 		goto out;
1443 
1444 	/* Grab the first contiguous region of buffer space. */
1445 	{
1446 		u_char *tba;
1447 		int tbc;
1448 
1449 		tba = tp->t_outq.c_cf;
1450 		tbc = ndqb(&tp->t_outq, 0);
1451 
1452 		(void)splserial();
1453 		PLCOM_LOCK(sc);
1454 
1455 		sc->sc_tba = tba;
1456 		sc->sc_tbc = tbc;
1457 	}
1458 
1459 	SET(tp->t_state, TS_BUSY);
1460 	sc->sc_tx_busy = 1;
1461 
1462 	/* Enable transmit completion interrupts if necessary. */
1463 	if (!ISSET(sc->sc_cr, CR_TIE)) {
1464 		SET(sc->sc_cr, CR_TIE);
1465 		bus_space_write_1(iot, ioh, plcom_cr, sc->sc_cr);
1466 	}
1467 
1468 	/* Output the first chunk of the contiguous buffer. */
1469 	{
1470 		int n;
1471 
1472 		n = sc->sc_tbc;
1473 		if (n > sc->sc_fifolen)
1474 			n = sc->sc_fifolen;
1475 		bus_space_write_multi_1(iot, ioh, plcom_dr, sc->sc_tba, n);
1476 		sc->sc_tbc -= n;
1477 		sc->sc_tba += n;
1478 	}
1479 	PLCOM_UNLOCK(sc);
1480 out:
1481 	splx(s);
1482 	return;
1483 }
1484 
1485 /*
1486  * Stop output on a line.
1487  */
1488 void
1489 plcomstop(struct tty *tp, int flag)
1490 {
1491 	struct plcom_softc *sc =
1492 		device_lookup_private(&plcom_cd, PLCOMUNIT(tp->t_dev));
1493 	int s;
1494 
1495 	s = splserial();
1496 	PLCOM_LOCK(sc);
1497 	if (ISSET(tp->t_state, TS_BUSY)) {
1498 		/* Stop transmitting at the next chunk. */
1499 		sc->sc_tbc = 0;
1500 		sc->sc_heldtbc = 0;
1501 		if (!ISSET(tp->t_state, TS_TTSTOP))
1502 			SET(tp->t_state, TS_FLUSH);
1503 	}
1504 	PLCOM_UNLOCK(sc);
1505 	splx(s);
1506 }
1507 
1508 void
1509 plcomdiag(void *arg)
1510 {
1511 	struct plcom_softc *sc = arg;
1512 	int overflows, floods;
1513 	int s;
1514 
1515 	s = splserial();
1516 	PLCOM_LOCK(sc);
1517 	overflows = sc->sc_overflows;
1518 	sc->sc_overflows = 0;
1519 	floods = sc->sc_floods;
1520 	sc->sc_floods = 0;
1521 	sc->sc_errors = 0;
1522 	PLCOM_UNLOCK(sc);
1523 	splx(s);
1524 
1525 	log(LOG_WARNING, "%s: %d silo overflow%s, %d ibuf flood%s\n",
1526 	    sc->sc_dev.dv_xname,
1527 	    overflows, overflows == 1 ? "" : "s",
1528 	    floods, floods == 1 ? "" : "s");
1529 }
1530 
1531 integrate void
1532 plcom_rxsoft(struct plcom_softc *sc, struct tty *tp)
1533 {
1534 	int (*rint) (int, struct tty *) = tp->t_linesw->l_rint;
1535 	u_char *get, *end;
1536 	u_int cc, scc;
1537 	u_char rsr;
1538 	int code;
1539 	int s;
1540 
1541 	end = sc->sc_ebuf;
1542 	get = sc->sc_rbget;
1543 	scc = cc = plcom_rbuf_size - sc->sc_rbavail;
1544 
1545 	if (cc == plcom_rbuf_size) {
1546 		sc->sc_floods++;
1547 		if (sc->sc_errors++ == 0)
1548 			callout_reset(&sc->sc_diag_callout, 60 * hz,
1549 			    plcomdiag, sc);
1550 	}
1551 
1552 	while (cc) {
1553 		code = get[0];
1554 		rsr = get[1];
1555 		if (ISSET(rsr, RSR_OE | RSR_BE | RSR_FE | RSR_PE)) {
1556 			if (ISSET(rsr, RSR_OE)) {
1557 				sc->sc_overflows++;
1558 				if (sc->sc_errors++ == 0)
1559 					callout_reset(&sc->sc_diag_callout,
1560 					    60 * hz, plcomdiag, sc);
1561 			}
1562 			if (ISSET(rsr, RSR_BE | RSR_FE))
1563 				SET(code, TTY_FE);
1564 			if (ISSET(rsr, RSR_PE))
1565 				SET(code, TTY_PE);
1566 		}
1567 		if ((*rint)(code, tp) == -1) {
1568 			/*
1569 			 * The line discipline's buffer is out of space.
1570 			 */
1571 			if (!ISSET(sc->sc_rx_flags, RX_TTY_BLOCKED)) {
1572 				/*
1573 				 * We're either not using flow control, or the
1574 				 * line discipline didn't tell us to block for
1575 				 * some reason.  Either way, we have no way to
1576 				 * know when there's more space available, so
1577 				 * just drop the rest of the data.
1578 				 */
1579 				get += cc << 1;
1580 				if (get >= end)
1581 					get -= plcom_rbuf_size << 1;
1582 				cc = 0;
1583 			} else {
1584 				/*
1585 				 * Don't schedule any more receive processing
1586 				 * until the line discipline tells us there's
1587 				 * space available (through plcomhwiflow()).
1588 				 * Leave the rest of the data in the input
1589 				 * buffer.
1590 				 */
1591 				SET(sc->sc_rx_flags, RX_TTY_OVERFLOWED);
1592 			}
1593 			break;
1594 		}
1595 		get += 2;
1596 		if (get >= end)
1597 			get = sc->sc_rbuf;
1598 		cc--;
1599 	}
1600 
1601 	if (cc != scc) {
1602 		sc->sc_rbget = get;
1603 		s = splserial();
1604 		PLCOM_LOCK(sc);
1605 
1606 		cc = sc->sc_rbavail += scc - cc;
1607 		/* Buffers should be ok again, release possible block. */
1608 		if (cc >= sc->sc_r_lowat) {
1609 			if (ISSET(sc->sc_rx_flags, RX_IBUF_OVERFLOWED)) {
1610 				CLR(sc->sc_rx_flags, RX_IBUF_OVERFLOWED);
1611 				SET(sc->sc_cr, CR_RIE | CR_RTIE);
1612 				bus_space_write_1(sc->sc_iot, sc->sc_ioh, plcom_cr, sc->sc_cr);
1613 			}
1614 			if (ISSET(sc->sc_rx_flags, RX_IBUF_BLOCKED)) {
1615 				CLR(sc->sc_rx_flags, RX_IBUF_BLOCKED);
1616 				plcom_hwiflow(sc);
1617 			}
1618 		}
1619 		PLCOM_UNLOCK(sc);
1620 		splx(s);
1621 	}
1622 }
1623 
1624 integrate void
1625 plcom_txsoft(struct plcom_softc *sc, struct tty *tp)
1626 {
1627 
1628 	CLR(tp->t_state, TS_BUSY);
1629 	if (ISSET(tp->t_state, TS_FLUSH))
1630 		CLR(tp->t_state, TS_FLUSH);
1631 	else
1632 		ndflush(&tp->t_outq, (int)(sc->sc_tba - tp->t_outq.c_cf));
1633 	(*tp->t_linesw->l_start)(tp);
1634 }
1635 
1636 integrate void
1637 plcom_stsoft(struct plcom_softc *sc, struct tty *tp)
1638 {
1639 	u_char msr, delta;
1640 	int s;
1641 
1642 	s = splserial();
1643 	PLCOM_LOCK(sc);
1644 	msr = sc->sc_msr;
1645 	delta = sc->sc_msr_delta;
1646 	sc->sc_msr_delta = 0;
1647 	PLCOM_UNLOCK(sc);
1648 	splx(s);
1649 
1650 	if (ISSET(delta, sc->sc_msr_dcd)) {
1651 		/*
1652 		 * Inform the tty layer that carrier detect changed.
1653 		 */
1654 		(void) (*tp->t_linesw->l_modem)(tp, ISSET(msr, MSR_DCD));
1655 	}
1656 
1657 	if (ISSET(delta, sc->sc_msr_cts)) {
1658 		/* Block or unblock output according to flow control. */
1659 		if (ISSET(msr, sc->sc_msr_cts)) {
1660 			sc->sc_tx_stopped = 0;
1661 			(*tp->t_linesw->l_start)(tp);
1662 		} else {
1663 			sc->sc_tx_stopped = 1;
1664 		}
1665 	}
1666 
1667 #ifdef PLCOM_DEBUG
1668 	if (plcom_debug)
1669 		plcomstatus(sc, "plcom_stsoft");
1670 #endif
1671 }
1672 
1673 void
1674 plcomsoft(void *arg)
1675 {
1676 	struct plcom_softc *sc = arg;
1677 	struct tty *tp;
1678 
1679 	if (PLCOM_ISALIVE(sc) == 0)
1680 		return;
1681 
1682 	tp = sc->sc_tty;
1683 
1684 	if (sc->sc_rx_ready) {
1685 		sc->sc_rx_ready = 0;
1686 		plcom_rxsoft(sc, tp);
1687 	}
1688 
1689 	if (sc->sc_st_check) {
1690 		sc->sc_st_check = 0;
1691 		plcom_stsoft(sc, tp);
1692 	}
1693 
1694 	if (sc->sc_tx_done) {
1695 		sc->sc_tx_done = 0;
1696 		plcom_txsoft(sc, tp);
1697 	}
1698 }
1699 
1700 int
1701 plcomintr(void *arg)
1702 {
1703 	struct plcom_softc *sc = arg;
1704 	bus_space_tag_t iot = sc->sc_iot;
1705 	bus_space_handle_t ioh = sc->sc_ioh;
1706 	u_char *put, *end;
1707 	u_int cc;
1708 	u_char rsr, iir;
1709 
1710 	if (PLCOM_ISALIVE(sc) == 0)
1711 		return 0;
1712 
1713 	PLCOM_LOCK(sc);
1714 	iir = bus_space_read_1(iot, ioh, plcom_iir);
1715 	if (! ISSET(iir, IIR_IMASK)) {
1716 		PLCOM_UNLOCK(sc);
1717 		return 0;
1718 	}
1719 
1720 	end = sc->sc_ebuf;
1721 	put = sc->sc_rbput;
1722 	cc = sc->sc_rbavail;
1723 
1724 	do {
1725 		u_char	msr, delta, fr;
1726 
1727 		fr = bus_space_read_1(iot, ioh, plcom_fr);
1728 
1729 		if (!ISSET(fr, FR_RXFE) &&
1730 		    !ISSET(sc->sc_rx_flags, RX_IBUF_OVERFLOWED)) {
1731 			while (cc > 0) {
1732 				int cn_trapped = 0;
1733 				put[0] = bus_space_read_1(iot, ioh,
1734 				    plcom_dr);
1735 				rsr = bus_space_read_1(iot, ioh, plcom_rsr);
1736 				/* Clear any error status.  */
1737 				if (ISSET(rsr,
1738 				    (RSR_BE | RSR_OE | RSR_PE | RSR_FE)))
1739 					bus_space_write_1(iot, ioh, plcom_ecr,
1740 					    0);
1741 				if (ISSET(rsr, RSR_BE)) {
1742 					cn_trapped = 0;
1743 					cn_check_magic(sc->sc_tty->t_dev,
1744 					    CNC_BREAK, plcom_cnm_state);
1745 					if (cn_trapped)
1746 						continue;
1747 #if defined(KGDB)
1748 					if (ISSET(sc->sc_hwflags,
1749 					    PLCOM_HW_KGDB)) {
1750 						kgdb_connect(1);
1751 						continue;
1752 					}
1753 #endif
1754 				}
1755 
1756 				put[1] = rsr;
1757 				cn_trapped = 0;
1758 				cn_check_magic(sc->sc_tty->t_dev,
1759 					       put[0], plcom_cnm_state);
1760 				if (cn_trapped) {
1761 					fr = bus_space_read_1(iot, ioh,
1762 					    plcom_fr);
1763 					if (ISSET(fr, FR_RXFE))
1764 						break;
1765 
1766 					continue;
1767 				}
1768 				put += 2;
1769 				if (put >= end)
1770 					put = sc->sc_rbuf;
1771 				cc--;
1772 
1773 				fr = bus_space_read_1(iot, ioh, plcom_fr);
1774 				if (ISSET(fr, FR_RXFE))
1775 					break;
1776 			}
1777 
1778 			/*
1779 			 * Current string of incoming characters ended because
1780 			 * no more data was available or we ran out of space.
1781 			 * Schedule a receive event if any data was received.
1782 			 * If we're out of space, turn off receive interrupts.
1783 			 */
1784 			sc->sc_rbput = put;
1785 			sc->sc_rbavail = cc;
1786 			if (!ISSET(sc->sc_rx_flags, RX_TTY_OVERFLOWED))
1787 				sc->sc_rx_ready = 1;
1788 
1789 			/*
1790 			 * See if we are in danger of overflowing a buffer. If
1791 			 * so, use hardware flow control to ease the pressure.
1792 			 */
1793 			if (!ISSET(sc->sc_rx_flags, RX_IBUF_BLOCKED) &&
1794 			    cc < sc->sc_r_hiwat) {
1795 				SET(sc->sc_rx_flags, RX_IBUF_BLOCKED);
1796 				plcom_hwiflow(sc);
1797 			}
1798 
1799 			/*
1800 			 * If we're out of space, disable receive interrupts
1801 			 * until the queue has drained a bit.
1802 			 */
1803 			if (!cc) {
1804 				SET(sc->sc_rx_flags, RX_IBUF_OVERFLOWED);
1805 				CLR(sc->sc_cr, CR_RIE | CR_RTIE);
1806 				bus_space_write_1(iot, ioh, plcom_cr,
1807 				    sc->sc_cr);
1808 			}
1809 		} else {
1810 			if (ISSET(iir, IIR_RIS)) {
1811 				bus_space_write_1(iot, ioh, plcom_cr, 0);
1812 				delay(10);
1813 				bus_space_write_1(iot, ioh, plcom_cr,
1814 				    sc->sc_cr);
1815 				continue;
1816 			}
1817 		}
1818 
1819 		msr = bus_space_read_1(iot, ioh, plcom_fr);
1820 		delta = msr ^ sc->sc_msr;
1821 		sc->sc_msr = msr;
1822 		/* Clear any pending modem status interrupt.  */
1823 		if (iir & IIR_MIS)
1824 			bus_space_write_1(iot, ioh, plcom_icr, 0);
1825 		/*
1826 		 * Pulse-per-second (PSS) signals on edge of DCD?
1827 		 * Process these even if line discipline is ignoring DCD.
1828 		 */
1829 		if (delta & sc->sc_ppsmask) {
1830 			struct timeval tv;
1831 			mutex_spin_enter(&timecounter_lock);
1832 		    	if ((msr & sc->sc_ppsmask) == sc->sc_ppsassert) {
1833 				/* XXX nanotime() */
1834 				microtime(&tv);
1835 				TIMEVAL_TO_TIMESPEC(&tv,
1836 				    &sc->ppsinfo.assert_timestamp);
1837 				if (sc->ppsparam.mode & PPS_OFFSETASSERT) {
1838 					timespecadd(&sc->ppsinfo.assert_timestamp,
1839 					    &sc->ppsparam.assert_offset,
1840 						    &sc->ppsinfo.assert_timestamp);
1841 				}
1842 
1843 #ifdef PPS_SYNC
1844 				if (sc->ppsparam.mode & PPS_HARDPPSONASSERT)
1845 					hardpps(&tv, tv.tv_usec);
1846 #endif
1847 				sc->ppsinfo.assert_sequence++;
1848 				sc->ppsinfo.current_mode = sc->ppsparam.mode;
1849 
1850 			} else if ((msr & sc->sc_ppsmask) == sc->sc_ppsclear) {
1851 				/* XXX nanotime() */
1852 				microtime(&tv);
1853 				TIMEVAL_TO_TIMESPEC(&tv,
1854 				    &sc->ppsinfo.clear_timestamp);
1855 				if (sc->ppsparam.mode & PPS_OFFSETCLEAR) {
1856 					timespecadd(&sc->ppsinfo.clear_timestamp,
1857 					    &sc->ppsparam.clear_offset,
1858 					    &sc->ppsinfo.clear_timestamp);
1859 				}
1860 
1861 #ifdef PPS_SYNC
1862 				if (sc->ppsparam.mode & PPS_HARDPPSONCLEAR)
1863 					hardpps(&tv, tv.tv_usec);
1864 #endif
1865 				sc->ppsinfo.clear_sequence++;
1866 				sc->ppsinfo.current_mode = sc->ppsparam.mode;
1867 			}
1868 			mutex_spin_exit(&timecounter_lock);
1869 		}
1870 
1871 		/*
1872 		 * Process normal status changes
1873 		 */
1874 		if (ISSET(delta, sc->sc_msr_mask)) {
1875 			SET(sc->sc_msr_delta, delta);
1876 
1877 			/*
1878 			 * Stop output immediately if we lose the output
1879 			 * flow control signal or carrier detect.
1880 			 */
1881 			if (ISSET(~msr, sc->sc_msr_mask)) {
1882 				sc->sc_tbc = 0;
1883 				sc->sc_heldtbc = 0;
1884 #ifdef PLCOM_DEBUG
1885 				if (plcom_debug)
1886 					plcomstatus(sc, "plcomintr  ");
1887 #endif
1888 			}
1889 
1890 			sc->sc_st_check = 1;
1891 		}
1892 
1893 		/*
1894 		 * Done handling any receive interrupts. See if data
1895 		 * can be * transmitted as well. Schedule tx done
1896 		 * event if no data left * and tty was marked busy.
1897 		 */
1898 		if (ISSET(iir, IIR_TIS)) {
1899 			/*
1900 			 * If we've delayed a parameter change, do it
1901 			 * now, and restart * output.
1902 			 */
1903 			if (sc->sc_heldchange) {
1904 				plcom_loadchannelregs(sc);
1905 				sc->sc_heldchange = 0;
1906 				sc->sc_tbc = sc->sc_heldtbc;
1907 				sc->sc_heldtbc = 0;
1908 			}
1909 
1910 			/*
1911 			 * Output the next chunk of the contiguous
1912 			 * buffer, if any.
1913 			 */
1914 			if (sc->sc_tbc > 0) {
1915 				int n;
1916 
1917 				n = sc->sc_tbc;
1918 				if (n > sc->sc_fifolen)
1919 					n = sc->sc_fifolen;
1920 				bus_space_write_multi_1(iot, ioh, plcom_dr,
1921 				    sc->sc_tba, n);
1922 				sc->sc_tbc -= n;
1923 				sc->sc_tba += n;
1924 			} else {
1925 				/*
1926 				 * Disable transmit plcompletion
1927 				 * interrupts if necessary.
1928 				 */
1929 				if (ISSET(sc->sc_cr, CR_TIE)) {
1930 					CLR(sc->sc_cr, CR_TIE);
1931 					bus_space_write_1(iot, ioh, plcom_cr,
1932 					    sc->sc_cr);
1933 				}
1934 				if (sc->sc_tx_busy) {
1935 					sc->sc_tx_busy = 0;
1936 					sc->sc_tx_done = 1;
1937 				}
1938 			}
1939 		}
1940 	} while (ISSET((iir = bus_space_read_1(iot, ioh, plcom_iir)),
1941 	    IIR_IMASK));
1942 
1943 	PLCOM_UNLOCK(sc);
1944 
1945 	/* Wake up the poller. */
1946 	softint_schedule(sc->sc_si);
1947 
1948 #if NRND > 0 && defined(RND_COM)
1949 	rnd_add_uint32(&sc->rnd_source, iir | rsr);
1950 #endif
1951 
1952 	return 1;
1953 }
1954 
1955 /*
1956  * The following functions are polled getc and putc routines, shared
1957  * by the console and kgdb glue.
1958  *
1959  * The read-ahead code is so that you can detect pending in-band
1960  * cn_magic in polled mode while doing output rather than having to
1961  * wait until the kernel decides it needs input.
1962  */
1963 
1964 #define MAX_READAHEAD	20
1965 static int plcom_readahead[MAX_READAHEAD];
1966 static int plcom_readaheadcount = 0;
1967 
1968 int
1969 plcom_common_getc(dev_t dev, bus_space_tag_t iot, bus_space_handle_t ioh)
1970 {
1971 	int s = splserial();
1972 	u_char stat, c;
1973 
1974 	/* got a character from reading things earlier */
1975 	if (plcom_readaheadcount > 0) {
1976 		int i;
1977 
1978 		c = plcom_readahead[0];
1979 		for (i = 1; i < plcom_readaheadcount; i++) {
1980 			plcom_readahead[i-1] = plcom_readahead[i];
1981 		}
1982 		plcom_readaheadcount--;
1983 		splx(s);
1984 		return c;
1985 	}
1986 
1987 	/* block until a character becomes available */
1988 	while (ISSET(stat = bus_space_read_1(iot, ioh, plcom_fr), FR_RXFE))
1989 		;
1990 
1991 	c = bus_space_read_1(iot, ioh, plcom_dr);
1992 	stat = bus_space_read_1(iot, ioh, plcom_iir);
1993 	{
1994 		int cn_trapped = 0; /* unused */
1995 #ifdef DDB
1996 		extern int db_active;
1997 		if (!db_active)
1998 #endif
1999 			cn_check_magic(dev, c, plcom_cnm_state);
2000 	}
2001 	splx(s);
2002 	return c;
2003 }
2004 
2005 void
2006 plcom_common_putc(dev_t dev, bus_space_tag_t iot, bus_space_handle_t ioh,
2007     int c)
2008 {
2009 	int s = splserial();
2010 	int timo;
2011 
2012 	int cin, stat;
2013 	if (plcom_readaheadcount < MAX_READAHEAD
2014 	     && !ISSET(stat = bus_space_read_1(iot, ioh, plcom_fr), FR_RXFE)) {
2015 		int cn_trapped = 0;
2016 		cin = bus_space_read_1(iot, ioh, plcom_dr);
2017 		stat = bus_space_read_1(iot, ioh, plcom_iir);
2018 		cn_check_magic(dev, cin, plcom_cnm_state);
2019 		plcom_readahead[plcom_readaheadcount++] = cin;
2020 	}
2021 
2022 	/* wait for any pending transmission to finish */
2023 	timo = 150000;
2024 	while (!ISSET(bus_space_read_1(iot, ioh, plcom_fr), FR_TXFE) && --timo)
2025 		continue;
2026 
2027 	bus_space_write_1(iot, ioh, plcom_dr, c);
2028 	PLCOM_BARRIER(iot, ioh, BR | BW);
2029 
2030 	/* wait for this transmission to complete */
2031 	timo = 1500000;
2032 	while (!ISSET(bus_space_read_1(iot, ioh, plcom_fr), FR_TXFE) && --timo)
2033 		continue;
2034 
2035 	splx(s);
2036 }
2037 
2038 /*
2039  * Initialize UART for use as console or KGDB line.
2040  */
2041 int
2042 plcominit(bus_space_tag_t iot, bus_addr_t iobase, int rate, int frequency,
2043     tcflag_t cflag, bus_space_handle_t *iohp)
2044 {
2045 	bus_space_handle_t ioh;
2046 
2047 	if (bus_space_map(iot, iobase, PLCOM_UART_SIZE, 0, &ioh))
2048 		return ENOMEM; /* ??? */
2049 
2050 	rate = plcomspeed(rate, frequency);
2051 	bus_space_write_1(iot, ioh, plcom_cr, 0);
2052 	bus_space_write_1(iot, ioh, plcom_dlbl, rate);
2053 	bus_space_write_1(iot, ioh, plcom_dlbh, rate >> 8);
2054 	bus_space_write_1(iot, ioh, plcom_lcr, cflag2lcr(cflag) | LCR_FEN);
2055 	bus_space_write_1(iot, ioh, plcom_cr, CR_UARTEN);
2056 
2057 #if 0
2058 	/* Ought to do something like this, but we have no sc to
2059 	   dereference. */
2060 	/* XXX device_unit() abuse */
2061 	sc->sc_set_mcr(sc->sc_set_mcr_arg, device_unit(&sc->sc_dev),
2062 	    MCR_DTR | MCR_RTS);
2063 #endif
2064 
2065 	*iohp = ioh;
2066 	return 0;
2067 }
2068 
2069 /*
2070  * Following are all routines needed for PLCOM to act as console
2071  */
2072 struct consdev plcomcons = {
2073 	NULL, NULL, plcomcngetc, plcomcnputc, plcomcnpollc, NULL,
2074 	NULL, NULL, NODEV, CN_NORMAL
2075 };
2076 
2077 
2078 int
2079 plcomcnattach(bus_space_tag_t iot, bus_addr_t iobase, int rate, int frequency,
2080     tcflag_t cflag, int unit)
2081 {
2082 	int res;
2083 
2084 	res = plcominit(iot, iobase, rate, frequency, cflag, &plcomconsioh);
2085 	if (res)
2086 		return res;
2087 
2088 	cn_tab = &plcomcons;
2089 	cn_init_magic(&plcom_cnm_state);
2090 	cn_set_magic("\047\001"); /* default magic is BREAK */
2091 
2092 	plcomconstag = iot;
2093 	plcomconsunit = unit;
2094 	plcomconsrate = rate;
2095 	plcomconscflag = cflag;
2096 
2097 	return 0;
2098 }
2099 
2100 void
2101 plcomcndetach(void)
2102 {
2103 	bus_space_unmap(plcomconstag, plcomconsioh, PLCOM_UART_SIZE);
2104 	plcomconstag = NULL;
2105 
2106 	cn_tab = NULL;
2107 }
2108 
2109 int
2110 plcomcngetc(dev_t dev)
2111 {
2112 	return plcom_common_getc(dev, plcomconstag, plcomconsioh);
2113 }
2114 
2115 /*
2116  * Console kernel output character routine.
2117  */
2118 void
2119 plcomcnputc(dev_t dev, int c)
2120 {
2121 	plcom_common_putc(dev, plcomconstag, plcomconsioh, c);
2122 }
2123 
2124 void
2125 plcomcnpollc(dev_t dev, int on)
2126 {
2127 
2128 }
2129 
2130 #ifdef KGDB
2131 int
2132 plcom_kgdb_attach(bus_space_tag_t iot, bus_addr_t iobase, int rate,
2133    int frequency, tcflag_t cflag, int unit)
2134 {
2135 	int res;
2136 
2137 	if (iot == plcomconstag && iobase == plcomconsunit)
2138 		return EBUSY; /* cannot share with console */
2139 
2140 	res = plcominit(iot, iobase, rate, frequency, cflag, &plcom_kgdb_ioh);
2141 	if (res)
2142 		return res;
2143 
2144 	kgdb_attach(plcom_kgdb_getc, plcom_kgdb_putc, NULL);
2145 	kgdb_dev = 123; /* unneeded, only to satisfy some tests */
2146 
2147 	plcom_kgdb_iot = iot;
2148 	plcom_kgdb_unit = unit;
2149 
2150 	return 0;
2151 }
2152 
2153 /* ARGSUSED */
2154 int
2155 plcom_kgdb_getc(void *arg)
2156 {
2157 	return plcom_common_getc(NODEV, plcom_kgdb_iot, plcom_kgdb_ioh);
2158 }
2159 
2160 /* ARGSUSED */
2161 void
2162 plcom_kgdb_putc(void *arg, int c)
2163 {
2164 	plcom_common_putc(NODEV, plcom_kgdb_iot, plcom_kgdb_ioh, c);
2165 }
2166 #endif /* KGDB */
2167 
2168 /* helper function to identify the plcom ports used by
2169  console or KGDB (and not yet autoconf attached) */
2170 int
2171 plcom_is_console(bus_space_tag_t iot, int unit,
2172     bus_space_handle_t *ioh)
2173 {
2174 	bus_space_handle_t help;
2175 
2176 	if (!plcomconsattached &&
2177 	    iot == plcomconstag && unit == plcomconsunit)
2178 		help = plcomconsioh;
2179 #ifdef KGDB
2180 	else if (!plcom_kgdb_attached &&
2181 	    iot == plcom_kgdb_iot && unit == plcom_kgdb_unit)
2182 		help = plcom_kgdb_ioh;
2183 #endif
2184 	else
2185 		return 0;
2186 
2187 	if (ioh)
2188 		*ioh = help;
2189 	return 1;
2190 }
2191