xref: /netbsd-src/sys/arch/evbarm/dev/plcom.c (revision 404fbe5fb94ca1e054339640cabb2801ce52dd30)
1 /*	$NetBSD: plcom.c,v 1.28 2008/06/11 23:24:43 cegger 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 1.28 2008/06/11 23:24:43 cegger 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(self, flags)
471 	struct device *self;
472 	int flags;
473 {
474 	struct plcom_softc *sc = (struct plcom_softc *)self;
475 	int maj, mn;
476 
477 	/* locate the major number */
478 	maj = cdevsw_lookup_major(&plcom_cdevsw);
479 
480 	/* Nuke the vnodes for any open instances. */
481 	mn = device_unit(self);
482 	vdevgone(maj, mn, mn, VCHR);
483 
484 	mn |= PLCOMDIALOUT_MASK;
485 	vdevgone(maj, mn, mn, VCHR);
486 
487 	/* Free the receive buffer. */
488 	free(sc->sc_rbuf, M_DEVBUF);
489 
490 	/* Detach and free the tty. */
491 	tty_detach(sc->sc_tty);
492 	ttyfree(sc->sc_tty);
493 
494 	/* Unhook the soft interrupt handler. */
495 	softint_disestablish(sc->sc_si);
496 
497 #if NRND > 0 && defined(RND_COM)
498 	/* Unhook the entropy source. */
499 	rnd_detach_source(&sc->rnd_source);
500 #endif
501 
502 	return 0;
503 }
504 
505 int
506 plcom_activate(struct device *self, enum devact act)
507 {
508 	struct plcom_softc *sc = (struct plcom_softc *)self;
509 	int s, rv = 0;
510 
511 	s = splserial();
512 	PLCOM_LOCK(sc);
513 	switch (act) {
514 	case DVACT_ACTIVATE:
515 		rv = EOPNOTSUPP;
516 		break;
517 
518 	case DVACT_DEACTIVATE:
519 		if (sc->sc_hwflags & (PLCOM_HW_CONSOLE|PLCOM_HW_KGDB)) {
520 			rv = EBUSY;
521 			break;
522 		}
523 
524 		if (sc->disable != NULL && sc->enabled != 0) {
525 			(*sc->disable)(sc);
526 			sc->enabled = 0;
527 		}
528 		break;
529 	}
530 
531 	PLCOM_UNLOCK(sc);
532 	splx(s);
533 	return rv;
534 }
535 
536 void
537 plcom_shutdown(struct plcom_softc *sc)
538 {
539 	struct tty *tp = sc->sc_tty;
540 	int s;
541 
542 	s = splserial();
543 	PLCOM_LOCK(sc);
544 
545 	/* If we were asserting flow control, then deassert it. */
546 	SET(sc->sc_rx_flags, RX_IBUF_BLOCKED);
547 	plcom_hwiflow(sc);
548 
549 	/* Clear any break condition set with TIOCSBRK. */
550 	plcom_break(sc, 0);
551 
552 	/* Turn off PPS capture on last close. */
553 	mutex_spin_enter(&timecounter_lock);
554 	sc->sc_ppsmask = 0;
555 	sc->ppsparam.mode = 0;
556 	mutex_spin_exit(&timecounter_lock);
557 
558 	/*
559 	 * Hang up if necessary.  Wait a bit, so the other side has time to
560 	 * notice even if we immediately open the port again.
561 	 * Avoid tsleeping above splhigh().
562 	 */
563 	if (ISSET(tp->t_cflag, HUPCL)) {
564 		plcom_modem(sc, 0);
565 		PLCOM_UNLOCK(sc);
566 		splx(s);
567 		/* XXX tsleep will only timeout */
568 		(void) tsleep(sc, TTIPRI, ttclos, hz);
569 		s = splserial();
570 		PLCOM_LOCK(sc);
571 	}
572 
573 	/* Turn off interrupts. */
574 	if (ISSET(sc->sc_hwflags, PLCOM_HW_CONSOLE))
575 		/* interrupt on break */
576 		sc->sc_cr = CR_RIE | CR_RTIE | CR_UARTEN;
577 	else
578 		sc->sc_cr = 0;
579 	bus_space_write_1(sc->sc_iot, sc->sc_ioh, plcom_cr, sc->sc_cr);
580 
581 	if (sc->disable) {
582 #ifdef DIAGNOSTIC
583 		if (!sc->enabled)
584 			panic("plcom_shutdown: not enabled?");
585 #endif
586 		(*sc->disable)(sc);
587 		sc->enabled = 0;
588 	}
589 	PLCOM_UNLOCK(sc);
590 	splx(s);
591 }
592 
593 int
594 plcomopen(dev_t dev, int flag, int mode, struct lwp *l)
595 {
596 	struct plcom_softc *sc;
597 	struct tty *tp;
598 	int s, s2;
599 	int error;
600 
601 	sc = device_lookup_private(&plcom_cd, PLCOMUNIT(dev));
602 	if (sc == NULL || !ISSET(sc->sc_hwflags, PLCOM_HW_DEV_OK) ||
603 		sc->sc_rbuf == NULL)
604 		return ENXIO;
605 
606 	if (!device_is_active(&sc->sc_dev))
607 		return ENXIO;
608 
609 #ifdef KGDB
610 	/*
611 	 * If this is the kgdb port, no other use is permitted.
612 	 */
613 	if (ISSET(sc->sc_hwflags, PLCOM_HW_KGDB))
614 		return EBUSY;
615 #endif
616 
617 	tp = sc->sc_tty;
618 
619 	if (kauth_authorize_device_tty(l->l_cred, KAUTH_DEVICE_TTY_OPEN, tp))
620 		return (EBUSY);
621 
622 	s = spltty();
623 
624 	/*
625 	 * Do the following iff this is a first open.
626 	 */
627 	if (!ISSET(tp->t_state, TS_ISOPEN) && tp->t_wopen == 0) {
628 		struct termios t;
629 
630 		tp->t_dev = dev;
631 
632 		s2 = splserial();
633 		PLCOM_LOCK(sc);
634 
635 		if (sc->enable) {
636 			if ((*sc->enable)(sc)) {
637 				PLCOM_UNLOCK(sc);
638 				splx(s2);
639 				splx(s);
640 				printf("%s: device enable failed\n",
641 				       sc->sc_dev.dv_xname);
642 				return EIO;
643 			}
644 			sc->enabled = 1;
645 			plcom_config(sc);
646 		}
647 
648 		/* Turn on interrupts. */
649 		/* IER_ERXRDY | IER_ERLS | IER_EMSC;  */
650 		sc->sc_cr = CR_RIE | CR_RTIE | CR_MSIE | CR_UARTEN;
651 		bus_space_write_1(sc->sc_iot, sc->sc_ioh, plcom_cr, sc->sc_cr);
652 
653 		/* Fetch the current modem control status, needed later. */
654 		sc->sc_msr = bus_space_read_1(sc->sc_iot, sc->sc_ioh, plcom_fr);
655 
656 		/* Clear PPS capture state on first open. */
657 
658 		mutex_spin_enter(&timecounter_lock);
659 		sc->sc_ppsmask = 0;
660 		sc->ppsparam.mode = 0;
661 		mutex_spin_exit(&timecounter_lock);
662 
663 		PLCOM_UNLOCK(sc);
664 		splx(s2);
665 
666 		/*
667 		 * Initialize the termios status to the defaults.  Add in the
668 		 * sticky bits from TIOCSFLAGS.
669 		 */
670 		t.c_ispeed = 0;
671 		if (ISSET(sc->sc_hwflags, PLCOM_HW_CONSOLE)) {
672 			t.c_ospeed = plcomconsrate;
673 			t.c_cflag = plcomconscflag;
674 		} else {
675 			t.c_ospeed = TTYDEF_SPEED;
676 			t.c_cflag = TTYDEF_CFLAG;
677 		}
678 		if (ISSET(sc->sc_swflags, TIOCFLAG_CLOCAL))
679 			SET(t.c_cflag, CLOCAL);
680 		if (ISSET(sc->sc_swflags, TIOCFLAG_CRTSCTS))
681 			SET(t.c_cflag, CRTSCTS);
682 		if (ISSET(sc->sc_swflags, TIOCFLAG_MDMBUF))
683 			SET(t.c_cflag, MDMBUF);
684 		/* Make sure plcomparam() will do something. */
685 		tp->t_ospeed = 0;
686 		(void) plcomparam(tp, &t);
687 		tp->t_iflag = TTYDEF_IFLAG;
688 		tp->t_oflag = TTYDEF_OFLAG;
689 		tp->t_lflag = TTYDEF_LFLAG;
690 		ttychars(tp);
691 		ttsetwater(tp);
692 
693 		s2 = splserial();
694 		PLCOM_LOCK(sc);
695 
696 		/*
697 		 * Turn on DTR.  We must always do this, even if carrier is not
698 		 * present, because otherwise we'd have to use TIOCSDTR
699 		 * immediately after setting CLOCAL, which applications do not
700 		 * expect.  We always assert DTR while the device is open
701 		 * unless explicitly requested to deassert it.
702 		 */
703 		plcom_modem(sc, 1);
704 
705 		/* Clear the input ring, and unblock. */
706 		sc->sc_rbput = sc->sc_rbget = sc->sc_rbuf;
707 		sc->sc_rbavail = plcom_rbuf_size;
708 		plcom_iflush(sc);
709 		CLR(sc->sc_rx_flags, RX_ANY_BLOCK);
710 		plcom_hwiflow(sc);
711 
712 #ifdef PLCOM_DEBUG
713 		if (plcom_debug)
714 			plcomstatus(sc, "plcomopen  ");
715 #endif
716 
717 		PLCOM_UNLOCK(sc);
718 		splx(s2);
719 	}
720 
721 	splx(s);
722 
723 	error = ttyopen(tp, PLCOMDIALOUT(dev), ISSET(flag, O_NONBLOCK));
724 	if (error)
725 		goto bad;
726 
727 	error = (*tp->t_linesw->l_open)(dev, tp);
728 	if (error)
729 		goto bad;
730 
731 	return 0;
732 
733 bad:
734 	if (!ISSET(tp->t_state, TS_ISOPEN) && tp->t_wopen == 0) {
735 		/*
736 		 * We failed to open the device, and nobody else had it opened.
737 		 * Clean up the state as appropriate.
738 		 */
739 		plcom_shutdown(sc);
740 	}
741 
742 	return error;
743 }
744 
745 int
746 plcomclose(dev_t dev, int flag, int mode, struct lwp *l)
747 {
748 	struct plcom_softc *sc =
749 		device_lookup_private(&plcom_cd, PLCOMUNIT(dev));
750 	struct tty *tp = sc->sc_tty;
751 
752 	/* XXX This is for cons.c. */
753 	if (!ISSET(tp->t_state, TS_ISOPEN))
754 		return 0;
755 
756 	(*tp->t_linesw->l_close)(tp, flag);
757 	ttyclose(tp);
758 
759 	if (PLCOM_ISALIVE(sc) == 0)
760 		return 0;
761 
762 	if (!ISSET(tp->t_state, TS_ISOPEN) && tp->t_wopen == 0) {
763 		/*
764 		 * Although we got a last close, the device may still be in
765 		 * use; e.g. if this was the dialout node, and there are still
766 		 * processes waiting for carrier on the non-dialout node.
767 		 */
768 		plcom_shutdown(sc);
769 	}
770 
771 	return 0;
772 }
773 
774 int
775 plcomread(dev_t dev, struct uio *uio, int flag)
776 {
777 	struct plcom_softc *sc =
778 		device_lookup_private(&plcom_cd, PLCOMUNIT(dev));
779 	struct tty *tp = sc->sc_tty;
780 
781 	if (PLCOM_ISALIVE(sc) == 0)
782 		return EIO;
783 
784 	return (*tp->t_linesw->l_read)(tp, uio, flag);
785 }
786 
787 int
788 plcomwrite(dev_t dev, struct uio *uio, int flag)
789 {
790 	struct plcom_softc *sc =
791 		device_lookup_private(&plcom_cd, PLCOMUNIT(dev));
792 	struct tty *tp = sc->sc_tty;
793 
794 	if (PLCOM_ISALIVE(sc) == 0)
795 		return EIO;
796 
797 	return (*tp->t_linesw->l_write)(tp, uio, flag);
798 }
799 
800 int
801 plcompoll(dev_t dev, int events, struct lwp *l)
802 {
803 	struct plcom_softc *sc =
804 		device_lookup_private(&plcom_cd, PLCOMUNIT(dev));
805 	struct tty *tp = sc->sc_tty;
806 
807 	if (PLCOM_ISALIVE(sc) == 0)
808 		return EIO;
809 
810 	return (*tp->t_linesw->l_poll)(tp, events, l);
811 }
812 
813 struct tty *
814 plcomtty(dev_t dev)
815 {
816 	struct plcom_softc *sc =
817 		device_lookup_private(&plcom_cd, PLCOMUNIT(dev));
818 	struct tty *tp = sc->sc_tty;
819 
820 	return tp;
821 }
822 
823 int
824 plcomioctl(dev_t dev, u_long cmd, void *data, int flag, struct lwp *l)
825 {
826 	struct plcom_softc *sc =
827 		device_lookup_private(&plcom_cd, PLCOMUNIT(dev));
828 	struct tty *tp = sc->sc_tty;
829 	int error;
830 	int s;
831 
832 	if (PLCOM_ISALIVE(sc) == 0)
833 		return EIO;
834 
835 	error = (*tp->t_linesw->l_ioctl)(tp, cmd, data, flag, l);
836 	if (error != EPASSTHROUGH)
837 		return error;
838 
839 	error = ttioctl(tp, cmd, data, flag, l);
840 	if (error != EPASSTHROUGH)
841 		return error;
842 
843 	error = 0;
844 
845 	s = splserial();
846 	PLCOM_LOCK(sc);
847 
848 	switch (cmd) {
849 	case TIOCSBRK:
850 		plcom_break(sc, 1);
851 		break;
852 
853 	case TIOCCBRK:
854 		plcom_break(sc, 0);
855 		break;
856 
857 	case TIOCSDTR:
858 		plcom_modem(sc, 1);
859 		break;
860 
861 	case TIOCCDTR:
862 		plcom_modem(sc, 0);
863 		break;
864 
865 	case TIOCGFLAGS:
866 		*(int *)data = sc->sc_swflags;
867 		break;
868 
869 	case TIOCSFLAGS:
870 		error = kauth_authorize_device_tty(l->l_cred,
871 		    KAUTH_DEVICE_TTY_PRIVSET, tp);
872 		if (error)
873 			break;
874 		sc->sc_swflags = *(int *)data;
875 		break;
876 
877 	case TIOCMSET:
878 	case TIOCMBIS:
879 	case TIOCMBIC:
880 		tiocm_to_plcom(sc, cmd, *(int *)data);
881 		break;
882 
883 	case TIOCMGET:
884 		*(int *)data = plcom_to_tiocm(sc);
885 		break;
886 
887 	case PPS_IOC_CREATE:
888 		break;
889 
890 	case PPS_IOC_DESTROY:
891 		break;
892 
893 	case PPS_IOC_GETPARAMS: {
894 		pps_params_t *pp;
895 		pp = (pps_params_t *)data;
896 		mutex_spin_enter(&timecounter_lock);
897 		*pp = sc->ppsparam;
898 		mutex_spin_exit(&timecounter_lock);
899 		break;
900 	}
901 
902 	case PPS_IOC_SETPARAMS: {
903 	  	pps_params_t *pp;
904 		int mode;
905 		pp = (pps_params_t *)data;
906 		mutex_spin_enter(&timecounter_lock);
907 		if (pp->mode & ~ppscap) {
908 			error = EINVAL;
909 			mutex_spin_exit(&timecounter_lock);
910 			break;
911 		}
912 		sc->ppsparam = *pp;
913 	 	/*
914 		 * Compute msr masks from user-specified timestamp state.
915 		 */
916 		mode = sc->ppsparam.mode;
917 #ifdef	PPS_SYNC
918 		if (mode & PPS_HARDPPSONASSERT) {
919 			mode |= PPS_CAPTUREASSERT;
920 			/* XXX revoke any previous HARDPPS source */
921 		}
922 		if (mode & PPS_HARDPPSONCLEAR) {
923 			mode |= PPS_CAPTURECLEAR;
924 			/* XXX revoke any previous HARDPPS source */
925 		}
926 #endif	/* PPS_SYNC */
927 		switch (mode & PPS_CAPTUREBOTH) {
928 		case 0:
929 			sc->sc_ppsmask = 0;
930 			break;
931 
932 		case PPS_CAPTUREASSERT:
933 			sc->sc_ppsmask = MSR_DCD;
934 			sc->sc_ppsassert = MSR_DCD;
935 			sc->sc_ppsclear = -1;
936 			break;
937 
938 		case PPS_CAPTURECLEAR:
939 			sc->sc_ppsmask = MSR_DCD;
940 			sc->sc_ppsassert = -1;
941 			sc->sc_ppsclear = 0;
942 			break;
943 
944 		case PPS_CAPTUREBOTH:
945 			sc->sc_ppsmask = MSR_DCD;
946 			sc->sc_ppsassert = MSR_DCD;
947 			sc->sc_ppsclear = 0;
948 			break;
949 
950 		default:
951 			error = EINVAL;
952 			break;
953 		}
954 		mutex_spin_exit(&timecounter_lock);
955 		break;
956 	}
957 
958 	case PPS_IOC_GETCAP:
959 		*(int*)data = ppscap;
960 		break;
961 
962 	case PPS_IOC_FETCH: {
963 		pps_info_t *pi;
964 		pi = (pps_info_t *)data;
965 		mutex_spin_enter(&timecounter_lock);
966 		*pi = sc->ppsinfo;
967 		mutex_spin_exit(&timecounter_lock);
968 		break;
969 	}
970 
971 	case TIOCDCDTIMESTAMP:	/* XXX old, overloaded  API used by xntpd v3 */
972 		/*
973 		 * Some GPS clocks models use the falling rather than
974 		 * rising edge as the on-the-second signal.
975 		 * The old API has no way to specify PPS polarity.
976 		 */
977 		mutex_spin_enter(&timecounter_lock);
978 		sc->sc_ppsmask = MSR_DCD;
979 #ifndef PPS_TRAILING_EDGE
980 		sc->sc_ppsassert = MSR_DCD;
981 		sc->sc_ppsclear = -1;
982 		TIMESPEC_TO_TIMEVAL((struct timeval *)data,
983 		    &sc->ppsinfo.assert_timestamp);
984 #else
985 		sc->sc_ppsassert = -1
986 		sc->sc_ppsclear = 0;
987 		TIMESPEC_TO_TIMEVAL((struct timeval *)data,
988 		    &sc->ppsinfo.clear_timestamp);
989 #endif
990 		mutex_spin_exit(&timecounter_lock);
991 		break;
992 
993 	default:
994 		error = EPASSTHROUGH;
995 		break;
996 	}
997 
998 	PLCOM_UNLOCK(sc);
999 	splx(s);
1000 
1001 #ifdef PLCOM_DEBUG
1002 	if (plcom_debug)
1003 		plcomstatus(sc, "plcomioctl ");
1004 #endif
1005 
1006 	return error;
1007 }
1008 
1009 integrate void
1010 plcom_schedrx(struct plcom_softc *sc)
1011 {
1012 
1013 	sc->sc_rx_ready = 1;
1014 
1015 	/* Wake up the poller. */
1016 	softint_schedule(sc->sc_si);
1017 }
1018 
1019 void
1020 plcom_break(struct plcom_softc *sc, int onoff)
1021 {
1022 
1023 	if (onoff)
1024 		SET(sc->sc_lcr, LCR_BRK);
1025 	else
1026 		CLR(sc->sc_lcr, LCR_BRK);
1027 
1028 	if (!sc->sc_heldchange) {
1029 		if (sc->sc_tx_busy) {
1030 			sc->sc_heldtbc = sc->sc_tbc;
1031 			sc->sc_tbc = 0;
1032 			sc->sc_heldchange = 1;
1033 		} else
1034 			plcom_loadchannelregs(sc);
1035 	}
1036 }
1037 
1038 void
1039 plcom_modem(struct plcom_softc *sc, int onoff)
1040 {
1041 
1042 	if (sc->sc_mcr_dtr == 0)
1043 		return;
1044 
1045 	if (onoff)
1046 		SET(sc->sc_mcr, sc->sc_mcr_dtr);
1047 	else
1048 		CLR(sc->sc_mcr, sc->sc_mcr_dtr);
1049 
1050 	if (!sc->sc_heldchange) {
1051 		if (sc->sc_tx_busy) {
1052 			sc->sc_heldtbc = sc->sc_tbc;
1053 			sc->sc_tbc = 0;
1054 			sc->sc_heldchange = 1;
1055 		} else
1056 			plcom_loadchannelregs(sc);
1057 	}
1058 }
1059 
1060 void
1061 tiocm_to_plcom(struct plcom_softc *sc, u_long how, int ttybits)
1062 {
1063 	u_char plcombits;
1064 
1065 	plcombits = 0;
1066 	if (ISSET(ttybits, TIOCM_DTR))
1067 		SET(plcombits, MCR_DTR);
1068 	if (ISSET(ttybits, TIOCM_RTS))
1069 		SET(plcombits, MCR_RTS);
1070 
1071 	switch (how) {
1072 	case TIOCMBIC:
1073 		CLR(sc->sc_mcr, plcombits);
1074 		break;
1075 
1076 	case TIOCMBIS:
1077 		SET(sc->sc_mcr, plcombits);
1078 		break;
1079 
1080 	case TIOCMSET:
1081 		CLR(sc->sc_mcr, MCR_DTR | MCR_RTS);
1082 		SET(sc->sc_mcr, plcombits);
1083 		break;
1084 	}
1085 
1086 	if (!sc->sc_heldchange) {
1087 		if (sc->sc_tx_busy) {
1088 			sc->sc_heldtbc = sc->sc_tbc;
1089 			sc->sc_tbc = 0;
1090 			sc->sc_heldchange = 1;
1091 		} else
1092 			plcom_loadchannelregs(sc);
1093 	}
1094 }
1095 
1096 int
1097 plcom_to_tiocm(struct plcom_softc *sc)
1098 {
1099 	u_char plcombits;
1100 	int ttybits = 0;
1101 
1102 	plcombits = sc->sc_mcr;
1103 	if (ISSET(plcombits, MCR_DTR))
1104 		SET(ttybits, TIOCM_DTR);
1105 	if (ISSET(plcombits, MCR_RTS))
1106 		SET(ttybits, TIOCM_RTS);
1107 
1108 	plcombits = sc->sc_msr;
1109 	if (ISSET(plcombits, MSR_DCD))
1110 		SET(ttybits, TIOCM_CD);
1111 	if (ISSET(plcombits, MSR_CTS))
1112 		SET(ttybits, TIOCM_CTS);
1113 	if (ISSET(plcombits, MSR_DSR))
1114 		SET(ttybits, TIOCM_DSR);
1115 
1116 	if (sc->sc_cr != 0)
1117 		SET(ttybits, TIOCM_LE);
1118 
1119 	return ttybits;
1120 }
1121 
1122 static u_char
1123 cflag2lcr(tcflag_t cflag)
1124 {
1125 	u_char lcr = 0;
1126 
1127 	switch (ISSET(cflag, CSIZE)) {
1128 	case CS5:
1129 		SET(lcr, LCR_5BITS);
1130 		break;
1131 	case CS6:
1132 		SET(lcr, LCR_6BITS);
1133 		break;
1134 	case CS7:
1135 		SET(lcr, LCR_7BITS);
1136 		break;
1137 	case CS8:
1138 		SET(lcr, LCR_8BITS);
1139 		break;
1140 	}
1141 	if (ISSET(cflag, PARENB)) {
1142 		SET(lcr, LCR_PEN);
1143 		if (!ISSET(cflag, PARODD))
1144 			SET(lcr, LCR_EPS);
1145 	}
1146 	if (ISSET(cflag, CSTOPB))
1147 		SET(lcr, LCR_STP2);
1148 
1149 	return lcr;
1150 }
1151 
1152 int
1153 plcomparam(struct tty *tp, struct termios *t)
1154 {
1155 	struct plcom_softc *sc =
1156 		device_lookup_private(&plcom_cd, PLCOMUNIT(tp->t_dev));
1157 	int ospeed;
1158 	u_char lcr;
1159 	int s;
1160 
1161 	if (PLCOM_ISALIVE(sc) == 0)
1162 		return EIO;
1163 
1164 	ospeed = plcomspeed(t->c_ospeed, sc->sc_frequency);
1165 
1166 	/* Check requested parameters. */
1167 	if (ospeed < 0)
1168 		return EINVAL;
1169 	if (t->c_ispeed && t->c_ispeed != t->c_ospeed)
1170 		return EINVAL;
1171 
1172 	/*
1173 	 * For the console, always force CLOCAL and !HUPCL, so that the port
1174 	 * is always active.
1175 	 */
1176 	if (ISSET(sc->sc_swflags, TIOCFLAG_SOFTCAR) ||
1177 	    ISSET(sc->sc_hwflags, PLCOM_HW_CONSOLE)) {
1178 		SET(t->c_cflag, CLOCAL);
1179 		CLR(t->c_cflag, HUPCL);
1180 	}
1181 
1182 	/*
1183 	 * If there were no changes, don't do anything.  This avoids dropping
1184 	 * input and improves performance when all we did was frob things like
1185 	 * VMIN and VTIME.
1186 	 */
1187 	if (tp->t_ospeed == t->c_ospeed &&
1188 	    tp->t_cflag == t->c_cflag)
1189 		return 0;
1190 
1191 	lcr = ISSET(sc->sc_lcr, LCR_BRK) | cflag2lcr(t->c_cflag);
1192 
1193 	s = splserial();
1194 	PLCOM_LOCK(sc);
1195 
1196 	sc->sc_lcr = lcr;
1197 
1198 	/*
1199 	 * PL010 has a fixed-length FIFO trigger point.
1200 	 */
1201 	if (ISSET(sc->sc_hwflags, PLCOM_HW_FIFO))
1202 		sc->sc_fifo = 1;
1203 	else
1204 		sc->sc_fifo = 0;
1205 
1206 	if (sc->sc_fifo)
1207 		SET(sc->sc_lcr, LCR_FEN);
1208 
1209 	/*
1210 	 * If we're not in a mode that assumes a connection is present, then
1211 	 * ignore carrier changes.
1212 	 */
1213 	if (ISSET(t->c_cflag, CLOCAL | MDMBUF))
1214 		sc->sc_msr_dcd = 0;
1215 	else
1216 		sc->sc_msr_dcd = MSR_DCD;
1217 	/*
1218 	 * Set the flow control pins depending on the current flow control
1219 	 * mode.
1220 	 */
1221 	if (ISSET(t->c_cflag, CRTSCTS)) {
1222 		sc->sc_mcr_dtr = MCR_DTR;
1223 		sc->sc_mcr_rts = MCR_RTS;
1224 		sc->sc_msr_cts = MSR_CTS;
1225 	} else if (ISSET(t->c_cflag, MDMBUF)) {
1226 		/*
1227 		 * For DTR/DCD flow control, make sure we don't toggle DTR for
1228 		 * carrier detection.
1229 		 */
1230 		sc->sc_mcr_dtr = 0;
1231 		sc->sc_mcr_rts = MCR_DTR;
1232 		sc->sc_msr_cts = MSR_DCD;
1233 	} else {
1234 		/*
1235 		 * If no flow control, then always set RTS.  This will make
1236 		 * the other side happy if it mistakenly thinks we're doing
1237 		 * RTS/CTS flow control.
1238 		 */
1239 		sc->sc_mcr_dtr = MCR_DTR | MCR_RTS;
1240 		sc->sc_mcr_rts = 0;
1241 		sc->sc_msr_cts = 0;
1242 		if (ISSET(sc->sc_mcr, MCR_DTR))
1243 			SET(sc->sc_mcr, MCR_RTS);
1244 		else
1245 			CLR(sc->sc_mcr, MCR_RTS);
1246 	}
1247 	sc->sc_msr_mask = sc->sc_msr_cts | sc->sc_msr_dcd;
1248 
1249 #if 0
1250 	if (ospeed == 0)
1251 		CLR(sc->sc_mcr, sc->sc_mcr_dtr);
1252 	else
1253 		SET(sc->sc_mcr, sc->sc_mcr_dtr);
1254 #endif
1255 
1256 	sc->sc_dlbl = ospeed;
1257 	sc->sc_dlbh = ospeed >> 8;
1258 
1259 	/* And copy to tty. */
1260 	tp->t_ispeed = 0;
1261 	tp->t_ospeed = t->c_ospeed;
1262 	tp->t_cflag = t->c_cflag;
1263 
1264 	if (!sc->sc_heldchange) {
1265 		if (sc->sc_tx_busy) {
1266 			sc->sc_heldtbc = sc->sc_tbc;
1267 			sc->sc_tbc = 0;
1268 			sc->sc_heldchange = 1;
1269 		} else
1270 			plcom_loadchannelregs(sc);
1271 	}
1272 
1273 	if (!ISSET(t->c_cflag, CHWFLOW)) {
1274 		/* Disable the high water mark. */
1275 		sc->sc_r_hiwat = 0;
1276 		sc->sc_r_lowat = 0;
1277 		if (ISSET(sc->sc_rx_flags, RX_TTY_OVERFLOWED)) {
1278 			CLR(sc->sc_rx_flags, RX_TTY_OVERFLOWED);
1279 			plcom_schedrx(sc);
1280 		}
1281 		if (ISSET(sc->sc_rx_flags, RX_TTY_BLOCKED|RX_IBUF_BLOCKED)) {
1282 			CLR(sc->sc_rx_flags, RX_TTY_BLOCKED|RX_IBUF_BLOCKED);
1283 			plcom_hwiflow(sc);
1284 		}
1285 	} else {
1286 		sc->sc_r_hiwat = plcom_rbuf_hiwat;
1287 		sc->sc_r_lowat = plcom_rbuf_lowat;
1288 	}
1289 
1290 	PLCOM_UNLOCK(sc);
1291 	splx(s);
1292 
1293 	/*
1294 	 * Update the tty layer's idea of the carrier bit, in case we changed
1295 	 * CLOCAL or MDMBUF.  We don't hang up here; we only do that by
1296 	 * explicit request.
1297 	 */
1298 	(void) (*tp->t_linesw->l_modem)(tp, ISSET(sc->sc_msr, MSR_DCD));
1299 
1300 #ifdef PLCOM_DEBUG
1301 	if (plcom_debug)
1302 		plcomstatus(sc, "plcomparam ");
1303 #endif
1304 
1305 	if (!ISSET(t->c_cflag, CHWFLOW)) {
1306 		if (sc->sc_tx_stopped) {
1307 			sc->sc_tx_stopped = 0;
1308 			plcomstart(tp);
1309 		}
1310 	}
1311 
1312 	return 0;
1313 }
1314 
1315 void
1316 plcom_iflush(struct plcom_softc *sc)
1317 {
1318 	bus_space_tag_t iot = sc->sc_iot;
1319 	bus_space_handle_t ioh = sc->sc_ioh;
1320 #ifdef DIAGNOSTIC
1321 	int reg;
1322 #endif
1323 	int timo;
1324 
1325 #ifdef DIAGNOSTIC
1326 	reg = 0xffff;
1327 #endif
1328 	timo = 50000;
1329 	/* flush any pending I/O */
1330 	while (! ISSET(bus_space_read_1(iot, ioh, plcom_fr), FR_RXFE)
1331 	    && --timo)
1332 #ifdef DIAGNOSTIC
1333 		reg =
1334 #else
1335 		    (void)
1336 #endif
1337 		    bus_space_read_1(iot, ioh, plcom_dr);
1338 #ifdef DIAGNOSTIC
1339 	if (!timo)
1340 		printf("%s: plcom_iflush timeout %02x\n", sc->sc_dev.dv_xname,
1341 		       reg);
1342 #endif
1343 }
1344 
1345 void
1346 plcom_loadchannelregs(struct plcom_softc *sc)
1347 {
1348 	bus_space_tag_t iot = sc->sc_iot;
1349 	bus_space_handle_t ioh = sc->sc_ioh;
1350 
1351 	/* XXXXX necessary? */
1352 	plcom_iflush(sc);
1353 
1354 	bus_space_write_1(iot, ioh, plcom_cr, 0);
1355 
1356 	bus_space_write_1(iot, ioh, plcom_dlbl, sc->sc_dlbl);
1357 	bus_space_write_1(iot, ioh, plcom_dlbh, sc->sc_dlbh);
1358 	bus_space_write_1(iot, ioh, plcom_lcr, sc->sc_lcr);
1359 	/* XXX device_unit() abuse */
1360 	sc->sc_set_mcr(sc->sc_set_mcr_arg, device_unit(&sc->sc_dev),
1361 	    sc->sc_mcr_active = sc->sc_mcr);
1362 
1363 	bus_space_write_1(iot, ioh, plcom_cr, sc->sc_cr);
1364 }
1365 
1366 int
1367 plcomhwiflow(struct tty *tp, int block)
1368 {
1369 	struct plcom_softc *sc =
1370 		device_lookup_private(&plcom_cd, PLCOMUNIT(tp->t_dev));
1371 	int s;
1372 
1373 	if (PLCOM_ISALIVE(sc) == 0)
1374 		return 0;
1375 
1376 	if (sc->sc_mcr_rts == 0)
1377 		return 0;
1378 
1379 	s = splserial();
1380 	PLCOM_LOCK(sc);
1381 
1382 	if (block) {
1383 		if (!ISSET(sc->sc_rx_flags, RX_TTY_BLOCKED)) {
1384 			SET(sc->sc_rx_flags, RX_TTY_BLOCKED);
1385 			plcom_hwiflow(sc);
1386 		}
1387 	} else {
1388 		if (ISSET(sc->sc_rx_flags, RX_TTY_OVERFLOWED)) {
1389 			CLR(sc->sc_rx_flags, RX_TTY_OVERFLOWED);
1390 			plcom_schedrx(sc);
1391 		}
1392 		if (ISSET(sc->sc_rx_flags, RX_TTY_BLOCKED)) {
1393 			CLR(sc->sc_rx_flags, RX_TTY_BLOCKED);
1394 			plcom_hwiflow(sc);
1395 		}
1396 	}
1397 
1398 	PLCOM_UNLOCK(sc);
1399 	splx(s);
1400 	return 1;
1401 }
1402 
1403 /*
1404  * (un)block input via hw flowcontrol
1405  */
1406 void
1407 plcom_hwiflow(struct plcom_softc *sc)
1408 {
1409 	if (sc->sc_mcr_rts == 0)
1410 		return;
1411 
1412 	if (ISSET(sc->sc_rx_flags, RX_ANY_BLOCK)) {
1413 		CLR(sc->sc_mcr, sc->sc_mcr_rts);
1414 		CLR(sc->sc_mcr_active, sc->sc_mcr_rts);
1415 	} else {
1416 		SET(sc->sc_mcr, sc->sc_mcr_rts);
1417 		SET(sc->sc_mcr_active, sc->sc_mcr_rts);
1418 	}
1419 	/* XXX device_unit() abuse */
1420 	sc->sc_set_mcr(sc->sc_set_mcr_arg, device_unit(&sc->sc_dev),
1421 	    sc->sc_mcr_active);
1422 }
1423 
1424 
1425 void
1426 plcomstart(struct tty *tp)
1427 {
1428 	struct plcom_softc *sc =
1429 		device_lookup_private(&plcom_cd, PLCOMUNIT(tp->t_dev));
1430 	bus_space_tag_t iot = sc->sc_iot;
1431 	bus_space_handle_t ioh = sc->sc_ioh;
1432 	int s;
1433 
1434 	if (PLCOM_ISALIVE(sc) == 0)
1435 		return;
1436 
1437 	s = spltty();
1438 	if (ISSET(tp->t_state, TS_BUSY | TS_TIMEOUT | TS_TTSTOP))
1439 		goto out;
1440 	if (sc->sc_tx_stopped)
1441 		goto out;
1442 
1443 	if (!ttypull(tp))
1444 		goto out;
1445 
1446 	/* Grab the first contiguous region of buffer space. */
1447 	{
1448 		u_char *tba;
1449 		int tbc;
1450 
1451 		tba = tp->t_outq.c_cf;
1452 		tbc = ndqb(&tp->t_outq, 0);
1453 
1454 		(void)splserial();
1455 		PLCOM_LOCK(sc);
1456 
1457 		sc->sc_tba = tba;
1458 		sc->sc_tbc = tbc;
1459 	}
1460 
1461 	SET(tp->t_state, TS_BUSY);
1462 	sc->sc_tx_busy = 1;
1463 
1464 	/* Enable transmit completion interrupts if necessary. */
1465 	if (!ISSET(sc->sc_cr, CR_TIE)) {
1466 		SET(sc->sc_cr, CR_TIE);
1467 		bus_space_write_1(iot, ioh, plcom_cr, sc->sc_cr);
1468 	}
1469 
1470 	/* Output the first chunk of the contiguous buffer. */
1471 	{
1472 		int n;
1473 
1474 		n = sc->sc_tbc;
1475 		if (n > sc->sc_fifolen)
1476 			n = sc->sc_fifolen;
1477 		bus_space_write_multi_1(iot, ioh, plcom_dr, sc->sc_tba, n);
1478 		sc->sc_tbc -= n;
1479 		sc->sc_tba += n;
1480 	}
1481 	PLCOM_UNLOCK(sc);
1482 out:
1483 	splx(s);
1484 	return;
1485 }
1486 
1487 /*
1488  * Stop output on a line.
1489  */
1490 void
1491 plcomstop(struct tty *tp, int flag)
1492 {
1493 	struct plcom_softc *sc =
1494 		device_lookup_private(&plcom_cd, PLCOMUNIT(tp->t_dev));
1495 	int s;
1496 
1497 	s = splserial();
1498 	PLCOM_LOCK(sc);
1499 	if (ISSET(tp->t_state, TS_BUSY)) {
1500 		/* Stop transmitting at the next chunk. */
1501 		sc->sc_tbc = 0;
1502 		sc->sc_heldtbc = 0;
1503 		if (!ISSET(tp->t_state, TS_TTSTOP))
1504 			SET(tp->t_state, TS_FLUSH);
1505 	}
1506 	PLCOM_UNLOCK(sc);
1507 	splx(s);
1508 }
1509 
1510 void
1511 plcomdiag(void *arg)
1512 {
1513 	struct plcom_softc *sc = arg;
1514 	int overflows, floods;
1515 	int s;
1516 
1517 	s = splserial();
1518 	PLCOM_LOCK(sc);
1519 	overflows = sc->sc_overflows;
1520 	sc->sc_overflows = 0;
1521 	floods = sc->sc_floods;
1522 	sc->sc_floods = 0;
1523 	sc->sc_errors = 0;
1524 	PLCOM_UNLOCK(sc);
1525 	splx(s);
1526 
1527 	log(LOG_WARNING, "%s: %d silo overflow%s, %d ibuf flood%s\n",
1528 	    sc->sc_dev.dv_xname,
1529 	    overflows, overflows == 1 ? "" : "s",
1530 	    floods, floods == 1 ? "" : "s");
1531 }
1532 
1533 integrate void
1534 plcom_rxsoft(struct plcom_softc *sc, struct tty *tp)
1535 {
1536 	int (*rint) (int, struct tty *) = tp->t_linesw->l_rint;
1537 	u_char *get, *end;
1538 	u_int cc, scc;
1539 	u_char rsr;
1540 	int code;
1541 	int s;
1542 
1543 	end = sc->sc_ebuf;
1544 	get = sc->sc_rbget;
1545 	scc = cc = plcom_rbuf_size - sc->sc_rbavail;
1546 
1547 	if (cc == plcom_rbuf_size) {
1548 		sc->sc_floods++;
1549 		if (sc->sc_errors++ == 0)
1550 			callout_reset(&sc->sc_diag_callout, 60 * hz,
1551 			    plcomdiag, sc);
1552 	}
1553 
1554 	while (cc) {
1555 		code = get[0];
1556 		rsr = get[1];
1557 		if (ISSET(rsr, RSR_OE | RSR_BE | RSR_FE | RSR_PE)) {
1558 			if (ISSET(rsr, RSR_OE)) {
1559 				sc->sc_overflows++;
1560 				if (sc->sc_errors++ == 0)
1561 					callout_reset(&sc->sc_diag_callout,
1562 					    60 * hz, plcomdiag, sc);
1563 			}
1564 			if (ISSET(rsr, RSR_BE | RSR_FE))
1565 				SET(code, TTY_FE);
1566 			if (ISSET(rsr, RSR_PE))
1567 				SET(code, TTY_PE);
1568 		}
1569 		if ((*rint)(code, tp) == -1) {
1570 			/*
1571 			 * The line discipline's buffer is out of space.
1572 			 */
1573 			if (!ISSET(sc->sc_rx_flags, RX_TTY_BLOCKED)) {
1574 				/*
1575 				 * We're either not using flow control, or the
1576 				 * line discipline didn't tell us to block for
1577 				 * some reason.  Either way, we have no way to
1578 				 * know when there's more space available, so
1579 				 * just drop the rest of the data.
1580 				 */
1581 				get += cc << 1;
1582 				if (get >= end)
1583 					get -= plcom_rbuf_size << 1;
1584 				cc = 0;
1585 			} else {
1586 				/*
1587 				 * Don't schedule any more receive processing
1588 				 * until the line discipline tells us there's
1589 				 * space available (through plcomhwiflow()).
1590 				 * Leave the rest of the data in the input
1591 				 * buffer.
1592 				 */
1593 				SET(sc->sc_rx_flags, RX_TTY_OVERFLOWED);
1594 			}
1595 			break;
1596 		}
1597 		get += 2;
1598 		if (get >= end)
1599 			get = sc->sc_rbuf;
1600 		cc--;
1601 	}
1602 
1603 	if (cc != scc) {
1604 		sc->sc_rbget = get;
1605 		s = splserial();
1606 		PLCOM_LOCK(sc);
1607 
1608 		cc = sc->sc_rbavail += scc - cc;
1609 		/* Buffers should be ok again, release possible block. */
1610 		if (cc >= sc->sc_r_lowat) {
1611 			if (ISSET(sc->sc_rx_flags, RX_IBUF_OVERFLOWED)) {
1612 				CLR(sc->sc_rx_flags, RX_IBUF_OVERFLOWED);
1613 				SET(sc->sc_cr, CR_RIE | CR_RTIE);
1614 				bus_space_write_1(sc->sc_iot, sc->sc_ioh, plcom_cr, sc->sc_cr);
1615 			}
1616 			if (ISSET(sc->sc_rx_flags, RX_IBUF_BLOCKED)) {
1617 				CLR(sc->sc_rx_flags, RX_IBUF_BLOCKED);
1618 				plcom_hwiflow(sc);
1619 			}
1620 		}
1621 		PLCOM_UNLOCK(sc);
1622 		splx(s);
1623 	}
1624 }
1625 
1626 integrate void
1627 plcom_txsoft(struct plcom_softc *sc, struct tty *tp)
1628 {
1629 
1630 	CLR(tp->t_state, TS_BUSY);
1631 	if (ISSET(tp->t_state, TS_FLUSH))
1632 		CLR(tp->t_state, TS_FLUSH);
1633 	else
1634 		ndflush(&tp->t_outq, (int)(sc->sc_tba - tp->t_outq.c_cf));
1635 	(*tp->t_linesw->l_start)(tp);
1636 }
1637 
1638 integrate void
1639 plcom_stsoft(struct plcom_softc *sc, struct tty *tp)
1640 {
1641 	u_char msr, delta;
1642 	int s;
1643 
1644 	s = splserial();
1645 	PLCOM_LOCK(sc);
1646 	msr = sc->sc_msr;
1647 	delta = sc->sc_msr_delta;
1648 	sc->sc_msr_delta = 0;
1649 	PLCOM_UNLOCK(sc);
1650 	splx(s);
1651 
1652 	if (ISSET(delta, sc->sc_msr_dcd)) {
1653 		/*
1654 		 * Inform the tty layer that carrier detect changed.
1655 		 */
1656 		(void) (*tp->t_linesw->l_modem)(tp, ISSET(msr, MSR_DCD));
1657 	}
1658 
1659 	if (ISSET(delta, sc->sc_msr_cts)) {
1660 		/* Block or unblock output according to flow control. */
1661 		if (ISSET(msr, sc->sc_msr_cts)) {
1662 			sc->sc_tx_stopped = 0;
1663 			(*tp->t_linesw->l_start)(tp);
1664 		} else {
1665 			sc->sc_tx_stopped = 1;
1666 		}
1667 	}
1668 
1669 #ifdef PLCOM_DEBUG
1670 	if (plcom_debug)
1671 		plcomstatus(sc, "plcom_stsoft");
1672 #endif
1673 }
1674 
1675 void
1676 plcomsoft(void *arg)
1677 {
1678 	struct plcom_softc *sc = arg;
1679 	struct tty *tp;
1680 
1681 	if (PLCOM_ISALIVE(sc) == 0)
1682 		return;
1683 
1684 	tp = sc->sc_tty;
1685 
1686 	if (sc->sc_rx_ready) {
1687 		sc->sc_rx_ready = 0;
1688 		plcom_rxsoft(sc, tp);
1689 	}
1690 
1691 	if (sc->sc_st_check) {
1692 		sc->sc_st_check = 0;
1693 		plcom_stsoft(sc, tp);
1694 	}
1695 
1696 	if (sc->sc_tx_done) {
1697 		sc->sc_tx_done = 0;
1698 		plcom_txsoft(sc, tp);
1699 	}
1700 }
1701 
1702 int
1703 plcomintr(void *arg)
1704 {
1705 	struct plcom_softc *sc = arg;
1706 	bus_space_tag_t iot = sc->sc_iot;
1707 	bus_space_handle_t ioh = sc->sc_ioh;
1708 	u_char *put, *end;
1709 	u_int cc;
1710 	u_char rsr, iir;
1711 
1712 	if (PLCOM_ISALIVE(sc) == 0)
1713 		return 0;
1714 
1715 	PLCOM_LOCK(sc);
1716 	iir = bus_space_read_1(iot, ioh, plcom_iir);
1717 	if (! ISSET(iir, IIR_IMASK)) {
1718 		PLCOM_UNLOCK(sc);
1719 		return 0;
1720 	}
1721 
1722 	end = sc->sc_ebuf;
1723 	put = sc->sc_rbput;
1724 	cc = sc->sc_rbavail;
1725 
1726 	do {
1727 		u_char	msr, delta, fr;
1728 
1729 		fr = bus_space_read_1(iot, ioh, plcom_fr);
1730 
1731 		if (!ISSET(fr, FR_RXFE) &&
1732 		    !ISSET(sc->sc_rx_flags, RX_IBUF_OVERFLOWED)) {
1733 			while (cc > 0) {
1734 				int cn_trapped = 0;
1735 				put[0] = bus_space_read_1(iot, ioh,
1736 				    plcom_dr);
1737 				rsr = bus_space_read_1(iot, ioh, plcom_rsr);
1738 				/* Clear any error status.  */
1739 				if (ISSET(rsr,
1740 				    (RSR_BE | RSR_OE | RSR_PE | RSR_FE)))
1741 					bus_space_write_1(iot, ioh, plcom_ecr,
1742 					    0);
1743 				if (ISSET(rsr, RSR_BE)) {
1744 					cn_trapped = 0;
1745 					cn_check_magic(sc->sc_tty->t_dev,
1746 					    CNC_BREAK, plcom_cnm_state);
1747 					if (cn_trapped)
1748 						continue;
1749 #if defined(KGDB)
1750 					if (ISSET(sc->sc_hwflags,
1751 					    PLCOM_HW_KGDB)) {
1752 						kgdb_connect(1);
1753 						continue;
1754 					}
1755 #endif
1756 				}
1757 
1758 				put[1] = rsr;
1759 				cn_trapped = 0;
1760 				cn_check_magic(sc->sc_tty->t_dev,
1761 					       put[0], plcom_cnm_state);
1762 				if (cn_trapped) {
1763 					fr = bus_space_read_1(iot, ioh,
1764 					    plcom_fr);
1765 					if (ISSET(fr, FR_RXFE))
1766 						break;
1767 
1768 					continue;
1769 				}
1770 				put += 2;
1771 				if (put >= end)
1772 					put = sc->sc_rbuf;
1773 				cc--;
1774 
1775 				fr = bus_space_read_1(iot, ioh, plcom_fr);
1776 				if (ISSET(fr, FR_RXFE))
1777 					break;
1778 			}
1779 
1780 			/*
1781 			 * Current string of incoming characters ended because
1782 			 * no more data was available or we ran out of space.
1783 			 * Schedule a receive event if any data was received.
1784 			 * If we're out of space, turn off receive interrupts.
1785 			 */
1786 			sc->sc_rbput = put;
1787 			sc->sc_rbavail = cc;
1788 			if (!ISSET(sc->sc_rx_flags, RX_TTY_OVERFLOWED))
1789 				sc->sc_rx_ready = 1;
1790 
1791 			/*
1792 			 * See if we are in danger of overflowing a buffer. If
1793 			 * so, use hardware flow control to ease the pressure.
1794 			 */
1795 			if (!ISSET(sc->sc_rx_flags, RX_IBUF_BLOCKED) &&
1796 			    cc < sc->sc_r_hiwat) {
1797 				SET(sc->sc_rx_flags, RX_IBUF_BLOCKED);
1798 				plcom_hwiflow(sc);
1799 			}
1800 
1801 			/*
1802 			 * If we're out of space, disable receive interrupts
1803 			 * until the queue has drained a bit.
1804 			 */
1805 			if (!cc) {
1806 				SET(sc->sc_rx_flags, RX_IBUF_OVERFLOWED);
1807 				CLR(sc->sc_cr, CR_RIE | CR_RTIE);
1808 				bus_space_write_1(iot, ioh, plcom_cr,
1809 				    sc->sc_cr);
1810 			}
1811 		} else {
1812 			if (ISSET(iir, IIR_RIS)) {
1813 				bus_space_write_1(iot, ioh, plcom_cr, 0);
1814 				delay(10);
1815 				bus_space_write_1(iot, ioh, plcom_cr,
1816 				    sc->sc_cr);
1817 				continue;
1818 			}
1819 		}
1820 
1821 		msr = bus_space_read_1(iot, ioh, plcom_fr);
1822 		delta = msr ^ sc->sc_msr;
1823 		sc->sc_msr = msr;
1824 		/* Clear any pending modem status interrupt.  */
1825 		if (iir & IIR_MIS)
1826 			bus_space_write_1(iot, ioh, plcom_icr, 0);
1827 		/*
1828 		 * Pulse-per-second (PSS) signals on edge of DCD?
1829 		 * Process these even if line discipline is ignoring DCD.
1830 		 */
1831 		if (delta & sc->sc_ppsmask) {
1832 			struct timeval tv;
1833 			mutex_spin_enter(&timecounter_lock);
1834 		    	if ((msr & sc->sc_ppsmask) == sc->sc_ppsassert) {
1835 				/* XXX nanotime() */
1836 				microtime(&tv);
1837 				TIMEVAL_TO_TIMESPEC(&tv,
1838 				    &sc->ppsinfo.assert_timestamp);
1839 				if (sc->ppsparam.mode & PPS_OFFSETASSERT) {
1840 					timespecadd(&sc->ppsinfo.assert_timestamp,
1841 					    &sc->ppsparam.assert_offset,
1842 						    &sc->ppsinfo.assert_timestamp);
1843 				}
1844 
1845 #ifdef PPS_SYNC
1846 				if (sc->ppsparam.mode & PPS_HARDPPSONASSERT)
1847 					hardpps(&tv, tv.tv_usec);
1848 #endif
1849 				sc->ppsinfo.assert_sequence++;
1850 				sc->ppsinfo.current_mode = sc->ppsparam.mode;
1851 
1852 			} else if ((msr & sc->sc_ppsmask) == sc->sc_ppsclear) {
1853 				/* XXX nanotime() */
1854 				microtime(&tv);
1855 				TIMEVAL_TO_TIMESPEC(&tv,
1856 				    &sc->ppsinfo.clear_timestamp);
1857 				if (sc->ppsparam.mode & PPS_OFFSETCLEAR) {
1858 					timespecadd(&sc->ppsinfo.clear_timestamp,
1859 					    &sc->ppsparam.clear_offset,
1860 					    &sc->ppsinfo.clear_timestamp);
1861 				}
1862 
1863 #ifdef PPS_SYNC
1864 				if (sc->ppsparam.mode & PPS_HARDPPSONCLEAR)
1865 					hardpps(&tv, tv.tv_usec);
1866 #endif
1867 				sc->ppsinfo.clear_sequence++;
1868 				sc->ppsinfo.current_mode = sc->ppsparam.mode;
1869 			}
1870 			mutex_spin_exit(&timecounter_lock);
1871 		}
1872 
1873 		/*
1874 		 * Process normal status changes
1875 		 */
1876 		if (ISSET(delta, sc->sc_msr_mask)) {
1877 			SET(sc->sc_msr_delta, delta);
1878 
1879 			/*
1880 			 * Stop output immediately if we lose the output
1881 			 * flow control signal or carrier detect.
1882 			 */
1883 			if (ISSET(~msr, sc->sc_msr_mask)) {
1884 				sc->sc_tbc = 0;
1885 				sc->sc_heldtbc = 0;
1886 #ifdef PLCOM_DEBUG
1887 				if (plcom_debug)
1888 					plcomstatus(sc, "plcomintr  ");
1889 #endif
1890 			}
1891 
1892 			sc->sc_st_check = 1;
1893 		}
1894 
1895 		/*
1896 		 * Done handling any receive interrupts. See if data
1897 		 * can be * transmitted as well. Schedule tx done
1898 		 * event if no data left * and tty was marked busy.
1899 		 */
1900 		if (ISSET(iir, IIR_TIS)) {
1901 			/*
1902 			 * If we've delayed a parameter change, do it
1903 			 * now, and restart * output.
1904 			 */
1905 			if (sc->sc_heldchange) {
1906 				plcom_loadchannelregs(sc);
1907 				sc->sc_heldchange = 0;
1908 				sc->sc_tbc = sc->sc_heldtbc;
1909 				sc->sc_heldtbc = 0;
1910 			}
1911 
1912 			/*
1913 			 * Output the next chunk of the contiguous
1914 			 * buffer, if any.
1915 			 */
1916 			if (sc->sc_tbc > 0) {
1917 				int n;
1918 
1919 				n = sc->sc_tbc;
1920 				if (n > sc->sc_fifolen)
1921 					n = sc->sc_fifolen;
1922 				bus_space_write_multi_1(iot, ioh, plcom_dr,
1923 				    sc->sc_tba, n);
1924 				sc->sc_tbc -= n;
1925 				sc->sc_tba += n;
1926 			} else {
1927 				/*
1928 				 * Disable transmit plcompletion
1929 				 * interrupts if necessary.
1930 				 */
1931 				if (ISSET(sc->sc_cr, CR_TIE)) {
1932 					CLR(sc->sc_cr, CR_TIE);
1933 					bus_space_write_1(iot, ioh, plcom_cr,
1934 					    sc->sc_cr);
1935 				}
1936 				if (sc->sc_tx_busy) {
1937 					sc->sc_tx_busy = 0;
1938 					sc->sc_tx_done = 1;
1939 				}
1940 			}
1941 		}
1942 	} while (ISSET((iir = bus_space_read_1(iot, ioh, plcom_iir)),
1943 	    IIR_IMASK));
1944 
1945 	PLCOM_UNLOCK(sc);
1946 
1947 	/* Wake up the poller. */
1948 	softint_schedule(sc->sc_si);
1949 
1950 #if NRND > 0 && defined(RND_COM)
1951 	rnd_add_uint32(&sc->rnd_source, iir | rsr);
1952 #endif
1953 
1954 	return 1;
1955 }
1956 
1957 /*
1958  * The following functions are polled getc and putc routines, shared
1959  * by the console and kgdb glue.
1960  *
1961  * The read-ahead code is so that you can detect pending in-band
1962  * cn_magic in polled mode while doing output rather than having to
1963  * wait until the kernel decides it needs input.
1964  */
1965 
1966 #define MAX_READAHEAD	20
1967 static int plcom_readahead[MAX_READAHEAD];
1968 static int plcom_readaheadcount = 0;
1969 
1970 int
1971 plcom_common_getc(dev_t dev, bus_space_tag_t iot, bus_space_handle_t ioh)
1972 {
1973 	int s = splserial();
1974 	u_char stat, c;
1975 
1976 	/* got a character from reading things earlier */
1977 	if (plcom_readaheadcount > 0) {
1978 		int i;
1979 
1980 		c = plcom_readahead[0];
1981 		for (i = 1; i < plcom_readaheadcount; i++) {
1982 			plcom_readahead[i-1] = plcom_readahead[i];
1983 		}
1984 		plcom_readaheadcount--;
1985 		splx(s);
1986 		return c;
1987 	}
1988 
1989 	/* block until a character becomes available */
1990 	while (ISSET(stat = bus_space_read_1(iot, ioh, plcom_fr), FR_RXFE))
1991 		;
1992 
1993 	c = bus_space_read_1(iot, ioh, plcom_dr);
1994 	stat = bus_space_read_1(iot, ioh, plcom_iir);
1995 	{
1996 		int cn_trapped = 0; /* unused */
1997 #ifdef DDB
1998 		extern int db_active;
1999 		if (!db_active)
2000 #endif
2001 			cn_check_magic(dev, c, plcom_cnm_state);
2002 	}
2003 	splx(s);
2004 	return c;
2005 }
2006 
2007 void
2008 plcom_common_putc(dev_t dev, bus_space_tag_t iot, bus_space_handle_t ioh,
2009     int c)
2010 {
2011 	int s = splserial();
2012 	int timo;
2013 
2014 	int cin, stat;
2015 	if (plcom_readaheadcount < MAX_READAHEAD
2016 	     && !ISSET(stat = bus_space_read_1(iot, ioh, plcom_fr), FR_RXFE)) {
2017 		int cn_trapped = 0;
2018 		cin = bus_space_read_1(iot, ioh, plcom_dr);
2019 		stat = bus_space_read_1(iot, ioh, plcom_iir);
2020 		cn_check_magic(dev, cin, plcom_cnm_state);
2021 		plcom_readahead[plcom_readaheadcount++] = cin;
2022 	}
2023 
2024 	/* wait for any pending transmission to finish */
2025 	timo = 150000;
2026 	while (!ISSET(bus_space_read_1(iot, ioh, plcom_fr), FR_TXFE) && --timo)
2027 		continue;
2028 
2029 	bus_space_write_1(iot, ioh, plcom_dr, c);
2030 	PLCOM_BARRIER(iot, ioh, BR | BW);
2031 
2032 	/* wait for this transmission to complete */
2033 	timo = 1500000;
2034 	while (!ISSET(bus_space_read_1(iot, ioh, plcom_fr), FR_TXFE) && --timo)
2035 		continue;
2036 
2037 	splx(s);
2038 }
2039 
2040 /*
2041  * Initialize UART for use as console or KGDB line.
2042  */
2043 int
2044 plcominit(bus_space_tag_t iot, bus_addr_t iobase, int rate, int frequency,
2045     tcflag_t cflag, bus_space_handle_t *iohp)
2046 {
2047 	bus_space_handle_t ioh;
2048 
2049 	if (bus_space_map(iot, iobase, PLCOM_UART_SIZE, 0, &ioh))
2050 		return ENOMEM; /* ??? */
2051 
2052 	rate = plcomspeed(rate, frequency);
2053 	bus_space_write_1(iot, ioh, plcom_cr, 0);
2054 	bus_space_write_1(iot, ioh, plcom_dlbl, rate);
2055 	bus_space_write_1(iot, ioh, plcom_dlbh, rate >> 8);
2056 	bus_space_write_1(iot, ioh, plcom_lcr, cflag2lcr(cflag) | LCR_FEN);
2057 	bus_space_write_1(iot, ioh, plcom_cr, CR_UARTEN);
2058 
2059 #if 0
2060 	/* Ought to do something like this, but we have no sc to
2061 	   dereference. */
2062 	/* XXX device_unit() abuse */
2063 	sc->sc_set_mcr(sc->sc_set_mcr_arg, device_unit(&sc->sc_dev),
2064 	    MCR_DTR | MCR_RTS);
2065 #endif
2066 
2067 	*iohp = ioh;
2068 	return 0;
2069 }
2070 
2071 /*
2072  * Following are all routines needed for PLCOM to act as console
2073  */
2074 struct consdev plcomcons = {
2075 	NULL, NULL, plcomcngetc, plcomcnputc, plcomcnpollc, NULL,
2076 	NULL, NULL, NODEV, CN_NORMAL
2077 };
2078 
2079 
2080 int
2081 plcomcnattach(bus_space_tag_t iot, bus_addr_t iobase, int rate, int frequency,
2082     tcflag_t cflag, int unit)
2083 {
2084 	int res;
2085 
2086 	res = plcominit(iot, iobase, rate, frequency, cflag, &plcomconsioh);
2087 	if (res)
2088 		return res;
2089 
2090 	cn_tab = &plcomcons;
2091 	cn_init_magic(&plcom_cnm_state);
2092 	cn_set_magic("\047\001"); /* default magic is BREAK */
2093 
2094 	plcomconstag = iot;
2095 	plcomconsunit = unit;
2096 	plcomconsrate = rate;
2097 	plcomconscflag = cflag;
2098 
2099 	return 0;
2100 }
2101 
2102 void
2103 plcomcndetach(void)
2104 {
2105 	bus_space_unmap(plcomconstag, plcomconsioh, PLCOM_UART_SIZE);
2106 	plcomconstag = NULL;
2107 
2108 	cn_tab = NULL;
2109 }
2110 
2111 int
2112 plcomcngetc(dev_t dev)
2113 {
2114 	return plcom_common_getc(dev, plcomconstag, plcomconsioh);
2115 }
2116 
2117 /*
2118  * Console kernel output character routine.
2119  */
2120 void
2121 plcomcnputc(dev_t dev, int c)
2122 {
2123 	plcom_common_putc(dev, plcomconstag, plcomconsioh, c);
2124 }
2125 
2126 void
2127 plcomcnpollc(dev_t dev, int on)
2128 {
2129 
2130 }
2131 
2132 #ifdef KGDB
2133 int
2134 plcom_kgdb_attach(bus_space_tag_t iot, bus_addr_t iobase, int rate,
2135    int frequency, tcflag_t cflag, int unit)
2136 {
2137 	int res;
2138 
2139 	if (iot == plcomconstag && iobase == plcomconsunit)
2140 		return EBUSY; /* cannot share with console */
2141 
2142 	res = plcominit(iot, iobase, rate, frequency, cflag, &plcom_kgdb_ioh);
2143 	if (res)
2144 		return res;
2145 
2146 	kgdb_attach(plcom_kgdb_getc, plcom_kgdb_putc, NULL);
2147 	kgdb_dev = 123; /* unneeded, only to satisfy some tests */
2148 
2149 	plcom_kgdb_iot = iot;
2150 	plcom_kgdb_unit = unit;
2151 
2152 	return 0;
2153 }
2154 
2155 /* ARGSUSED */
2156 int
2157 plcom_kgdb_getc(void *arg)
2158 {
2159 	return plcom_common_getc(NODEV, plcom_kgdb_iot, plcom_kgdb_ioh);
2160 }
2161 
2162 /* ARGSUSED */
2163 void
2164 plcom_kgdb_putc(void *arg, int c)
2165 {
2166 	plcom_common_putc(NODEV, plcom_kgdb_iot, plcom_kgdb_ioh, c);
2167 }
2168 #endif /* KGDB */
2169 
2170 /* helper function to identify the plcom ports used by
2171  console or KGDB (and not yet autoconf attached) */
2172 int
2173 plcom_is_console(bus_space_tag_t iot, int unit,
2174     bus_space_handle_t *ioh)
2175 {
2176 	bus_space_handle_t help;
2177 
2178 	if (!plcomconsattached &&
2179 	    iot == plcomconstag && unit == plcomconsunit)
2180 		help = plcomconsioh;
2181 #ifdef KGDB
2182 	else if (!plcom_kgdb_attached &&
2183 	    iot == plcom_kgdb_iot && unit == plcom_kgdb_unit)
2184 		help = plcom_kgdb_ioh;
2185 #endif
2186 	else
2187 		return 0;
2188 
2189 	if (ioh)
2190 		*ioh = help;
2191 	return 1;
2192 }
2193