xref: /netbsd/sys/arch/evbarm/dev/plcom.c (revision bf9ec67e)
1 /*	$NetBSD: plcom.c,v 1.3 2002/03/17 19:40:37 atatat 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  * 3. All advertising materials mentioning features or use of this software
46  *    must display the following acknowledgement:
47  *        This product includes software developed by the NetBSD
48  *        Foundation, Inc. and its contributors.
49  * 4. Neither the name of The NetBSD Foundation nor the names of its
50  *    contributors may be used to endorse or promote products derived
51  *    from this software without specific prior written permission.
52  *
53  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
54  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
55  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
56  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
57  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
58  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
59  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
60  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
61  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
62  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
63  * POSSIBILITY OF SUCH DAMAGE.
64  */
65 
66 /*
67  * Copyright (c) 1991 The Regents of the University of California.
68  * All rights reserved.
69  *
70  * Redistribution and use in source and binary forms, with or without
71  * modification, are permitted provided that the following conditions
72  * are met:
73  * 1. Redistributions of source code must retain the above copyright
74  *    notice, this list of conditions and the following disclaimer.
75  * 2. Redistributions in binary form must reproduce the above copyright
76  *    notice, this list of conditions and the following disclaimer in the
77  *    documentation and/or other materials provided with the distribution.
78  * 3. All advertising materials mentioning features or use of this software
79  *    must display the following acknowledgement:
80  *	This product includes software developed by the University of
81  *	California, Berkeley and its contributors.
82  * 4. Neither the name of the University nor the names of its contributors
83  *    may be used to endorse or promote products derived from this software
84  *    without specific prior written permission.
85  *
86  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
87  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
88  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
89  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
90  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
91  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
92  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
93  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
94  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
95  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
96  * SUCH DAMAGE.
97  *
98  *	@(#)com.c	7.5 (Berkeley) 5/16/91
99  */
100 
101 /*
102  * COM driver for the Prime Cell PL010 UART, which is similar to the 16C550,
103  * but has a completely different programmer's model.
104  * Derived from the NS16550AF com driver.
105  */
106 
107 #include "opt_plcom.h"
108 #include "opt_ddb.h"
109 #include "opt_kgdb.h"
110 
111 #include "rnd.h"
112 #if NRND > 0 && defined(RND_COM)
113 #include <sys/rnd.h>
114 #endif
115 
116 /*
117  * Override cnmagic(9) macro before including <sys/systm.h>.
118  * We need to know if cn_check_magic triggered debugger, so set a flag.
119  * Callers of cn_check_magic must declare int cn_trapped = 0;
120  * XXX: this is *ugly*!
121  */
122 #define cn_trap()				\
123 	do {					\
124 		console_debugger();		\
125 		cn_trapped = 1;			\
126 	} while (/* CONSTCOND */ 0)
127 
128 #include <sys/param.h>
129 #include <sys/systm.h>
130 #include <sys/ioctl.h>
131 #include <sys/select.h>
132 #include <sys/tty.h>
133 #include <sys/proc.h>
134 #include <sys/user.h>
135 #include <sys/conf.h>
136 #include <sys/file.h>
137 #include <sys/uio.h>
138 #include <sys/kernel.h>
139 #include <sys/syslog.h>
140 #include <sys/types.h>
141 #include <sys/device.h>
142 #include <sys/malloc.h>
143 #include <sys/timepps.h>
144 #include <sys/vnode.h>
145 
146 #include <machine/intr.h>
147 #include <machine/bus.h>
148 
149 #include <evbarm/dev/plcomreg.h>
150 #include <evbarm/dev/plcomvar.h>
151 
152 #include <dev/cons.h>
153 
154 static void plcom_enable_debugport (struct plcom_softc *);
155 
156 void	plcom_config	(struct plcom_softc *);
157 void	plcom_shutdown	(struct plcom_softc *);
158 int	plcomspeed	(long, long);
159 static	u_char	cflag2lcr (tcflag_t);
160 int	plcomparam	(struct tty *, struct termios *);
161 void	plcomstart	(struct tty *);
162 int	plcomhwiflow	(struct tty *, int);
163 
164 void	plcom_loadchannelregs (struct plcom_softc *);
165 void	plcom_hwiflow	(struct plcom_softc *);
166 void	plcom_break	(struct plcom_softc *, int);
167 void	plcom_modem	(struct plcom_softc *, int);
168 void	tiocm_to_plcom	(struct plcom_softc *, u_long, int);
169 int	plcom_to_tiocm	(struct plcom_softc *);
170 void	plcom_iflush	(struct plcom_softc *);
171 
172 int	plcom_common_getc (dev_t, bus_space_tag_t, bus_space_handle_t);
173 void	plcom_common_putc (dev_t, bus_space_tag_t, bus_space_handle_t, int);
174 
175 int	plcominit	(bus_space_tag_t, bus_addr_t, int, int, tcflag_t,
176 			    bus_space_handle_t *);
177 
178 /* XXX: This belongs elsewhere */
179 cdev_decl(plcom);
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 #ifdef __HAVE_GENERIC_SOFT_INTERRUPTS
187 void 	plcomsoft	(void *);
188 #else
189 #ifndef __NO_SOFT_SERIAL_INTERRUPT
190 void 	plcomsoft	(void);
191 #else
192 void 	plcomsoft	(void *);
193 struct callout plcomsoft_callout = CALLOUT_INITIALIZER;
194 #endif
195 #endif
196 integrate void plcom_rxsoft	(struct plcom_softc *, struct tty *);
197 integrate void plcom_txsoft	(struct plcom_softc *, struct tty *);
198 integrate void plcom_stsoft	(struct plcom_softc *, struct tty *);
199 integrate void plcom_schedrx	(struct plcom_softc *);
200 void	plcomdiag		(void *);
201 
202 extern struct cfdriver plcom_cd;
203 
204 /*
205  * Make this an option variable one can patch.
206  * But be warned:  this must be a power of 2!
207  */
208 u_int plcom_rbuf_size = PLCOM_RING_SIZE;
209 
210 /* Stop input when 3/4 of the ring is full; restart when only 1/4 is full. */
211 u_int plcom_rbuf_hiwat = (PLCOM_RING_SIZE * 1) / 4;
212 u_int plcom_rbuf_lowat = (PLCOM_RING_SIZE * 3) / 4;
213 
214 static int	plcomconsunit = -1;
215 static bus_space_tag_t plcomconstag;
216 static bus_space_handle_t plcomconsioh;
217 static int	plcomconsattached;
218 static int plcomconsrate;
219 static tcflag_t plcomconscflag;
220 static struct cnm_state plcom_cnm_state;
221 
222 static int ppscap =
223 	PPS_TSFMT_TSPEC |
224 	PPS_CAPTUREASSERT |
225 	PPS_CAPTURECLEAR |
226 #ifdef  PPS_SYNC
227 	PPS_HARDPPSONASSERT | PPS_HARDPPSONCLEAR |
228 #endif	/* PPS_SYNC */
229 	PPS_OFFSETASSERT | PPS_OFFSETCLEAR;
230 
231 #ifndef __HAVE_GENERIC_SOFT_INTERRUPTS
232 #ifdef __NO_SOFT_SERIAL_INTERRUPT
233 volatile int	plcom_softintr_scheduled;
234 #endif
235 #endif
236 
237 #ifdef KGDB
238 #include <sys/kgdb.h>
239 
240 static int plcom_kgdb_unit;
241 static bus_space_tag_t plcom_kgdb_iot;
242 static bus_space_handle_t plcom_kgdb_ioh;
243 static int plcom_kgdb_attached;
244 
245 int	plcom_kgdb_getc (void *);
246 void	plcom_kgdb_putc (void *, int);
247 #endif /* KGDB */
248 
249 #define	PLCOMUNIT_MASK	0x7ffff
250 #define	PLCOMDIALOUT_MASK	0x80000
251 
252 #define	PLCOMUNIT(x)	(minor(x) & PLCOMUNIT_MASK)
253 #define	PLCOMDIALOUT(x)	(minor(x) & PLCOMDIALOUT_MASK)
254 
255 #define	PLCOM_ISALIVE(sc)	((sc)->enabled != 0 && \
256 			 ISSET((sc)->sc_dev.dv_flags, DVF_ACTIVE))
257 
258 #define	BR	BUS_SPACE_BARRIER_READ
259 #define	BW	BUS_SPACE_BARRIER_WRITE
260 #define PLCOM_BARRIER(t, h, f) bus_space_barrier((t), (h), 0, PLCOM_UART_SIZE, (f))
261 
262 #if (defined(MULTIPROCESSOR) || defined(LOCKDEBUG)) && defined(PLCOM_MPLOCK)
263 
264 #define PLCOM_LOCK(sc) simple_lock(&(sc)->sc_lock)
265 #define PLCOM_UNLOCK(sc) simple_unlock(&(sc)->sc_lock)
266 
267 #else
268 
269 #define PLCOM_LOCK(sc)
270 #define PLCOM_UNLOCK(sc)
271 
272 #endif
273 
274 int
275 plcomspeed(long speed, long frequency)
276 {
277 #define	divrnd(n, q)	(((n)*2/(q)+1)/2)	/* divide and round off */
278 
279 	int x, err;
280 
281 #if 0
282 	if (speed == 0)
283 		return 0;
284 #endif
285 	if (speed <= 0)
286 		return -1;
287 	x = divrnd(frequency / 16, speed);
288 	if (x <= 0)
289 		return -1;
290 	err = divrnd(((quad_t)frequency) * 1000 / 16, speed * x) - 1000;
291 	if (err < 0)
292 		err = -err;
293 	if (err > PLCOM_TOLERANCE)
294 		return -1;
295 	return x;
296 
297 #undef	divrnd
298 }
299 
300 #ifdef PLCOM_DEBUG
301 int	plcom_debug = 0;
302 
303 void plcomstatus (struct plcom_softc *, char *);
304 void
305 plcomstatus(struct plcom_softc *sc, char *str)
306 {
307 	struct tty *tp = sc->sc_tty;
308 
309 	printf("%s: %s %sclocal  %sdcd %sts_carr_on %sdtr %stx_stopped\n",
310 	    sc->sc_dev.dv_xname, str,
311 	    ISSET(tp->t_cflag, CLOCAL) ? "+" : "-",
312 	    ISSET(sc->sc_msr, MSR_DCD) ? "+" : "-",
313 	    ISSET(tp->t_state, TS_CARR_ON) ? "+" : "-",
314 	    ISSET(sc->sc_mcr, MCR_DTR) ? "+" : "-",
315 	    sc->sc_tx_stopped ? "+" : "-");
316 
317 	printf("%s: %s %scrtscts %scts %sts_ttstop  %srts %xrx_flags\n",
318 	    sc->sc_dev.dv_xname, str,
319 	    ISSET(tp->t_cflag, CRTSCTS) ? "+" : "-",
320 	    ISSET(sc->sc_msr, MSR_CTS) ? "+" : "-",
321 	    ISSET(tp->t_state, TS_TTSTOP) ? "+" : "-",
322 	    ISSET(sc->sc_mcr, MCR_RTS) ? "+" : "-",
323 	    sc->sc_rx_flags);
324 }
325 #endif
326 
327 int
328 plcomprobe1(bus_space_tag_t iot, bus_space_handle_t ioh)
329 {
330 	int data;
331 
332 	/* Disable the UART.  */
333 	bus_space_write_1(iot, ioh, plcom_cr, 0);
334 	/* Make sure the FIFO is off.  */
335 	bus_space_write_1(iot, ioh, plcom_lcr, LCR_8BITS);
336 	/* Disable interrupts.  */
337 	bus_space_write_1(iot, ioh, plcom_iir, 0);
338 
339 	/* Make sure we swallow anything in the receiving register.  */
340 	data = bus_space_read_1(iot, ioh, plcom_dr);
341 
342 	if (bus_space_read_1(iot, ioh, plcom_lcr) != LCR_8BITS)
343 		return 0;
344 
345 	data = bus_space_read_1(iot, ioh, plcom_fr) & (FR_RXFF | FR_RXFE);
346 
347 	if (data != FR_RXFE)
348 		return 0;
349 
350 	return 1;
351 }
352 
353 static void
354 plcom_enable_debugport(struct plcom_softc *sc)
355 {
356 	int s;
357 
358 	/* Turn on line break interrupt, set carrier. */
359 	s = splserial();
360 	PLCOM_LOCK(sc);
361 	sc->sc_cr = CR_RIE | CR_RTIE | CR_UARTEN;
362 	bus_space_write_1(sc->sc_iot, sc->sc_ioh, plcom_cr, sc->sc_cr);
363 	SET(sc->sc_mcr, MCR_DTR | MCR_RTS);
364 	sc->sc_set_mcr(sc->sc_set_mcr_arg, sc->sc_dev.dv_unit, sc->sc_mcr);
365 	PLCOM_UNLOCK(sc);
366 	splx(s);
367 }
368 
369 void
370 plcom_attach_subr(struct plcom_softc *sc)
371 {
372 	int unit = sc->sc_iounit;
373 	bus_space_tag_t iot = sc->sc_iot;
374 	bus_space_handle_t ioh = sc->sc_ioh;
375 	struct tty *tp;
376 
377 	callout_init(&sc->sc_diag_callout);
378 #if (defined(MULTIPROCESSOR) || defined(LOCKDEBUG)) && defined(PLCOM_MPLOCK)
379 	simple_lock_init(&sc->sc_lock);
380 #endif
381 
382 	/* Disable interrupts before configuring the device. */
383 	sc->sc_cr = 0;
384 
385 	if (plcomconstag && unit == plcomconsunit) {
386 		plcomconsattached = 1;
387 
388 		plcomconstag = iot;
389 		plcomconsioh = ioh;
390 
391 		/* Make sure the console is always "hardwired". */
392 		delay(1000);			/* wait for output to finish */
393 		SET(sc->sc_hwflags, PLCOM_HW_CONSOLE);
394 		SET(sc->sc_swflags, TIOCFLAG_SOFTCAR);
395 		/* Must re-enable the console immediately, or we will
396 		   hang when trying to print.  */
397 		sc->sc_cr = CR_UARTEN;
398 	}
399 
400 	bus_space_write_1(iot, ioh, plcom_cr, sc->sc_cr);
401 
402 	/* The PL010 has a 16-byte fifo, but the tx interrupt triggers when
403 	   there is space for 8 more bytes.  */
404 	sc->sc_fifolen = 8;
405 	printf("\n");
406 
407 	if (ISSET(sc->sc_hwflags, PLCOM_HW_TXFIFO_DISABLE)) {
408 		sc->sc_fifolen = 1;
409 		printf("%s: txfifo disabled\n", sc->sc_dev.dv_xname);
410 	}
411 
412 	if (sc->sc_fifolen > 1)
413 		SET(sc->sc_hwflags, PLCOM_HW_FIFO);
414 
415 	tp = ttymalloc();
416 	tp->t_oproc = plcomstart;
417 	tp->t_param = plcomparam;
418 	tp->t_hwiflow = plcomhwiflow;
419 
420 	sc->sc_tty = tp;
421 	sc->sc_rbuf = malloc(plcom_rbuf_size << 1, M_DEVBUF, M_NOWAIT);
422 	sc->sc_rbput = sc->sc_rbget = sc->sc_rbuf;
423 	sc->sc_rbavail = plcom_rbuf_size;
424 	if (sc->sc_rbuf == NULL) {
425 		printf("%s: unable to allocate ring buffer\n",
426 		    sc->sc_dev.dv_xname);
427 		return;
428 	}
429 	sc->sc_ebuf = sc->sc_rbuf + (plcom_rbuf_size << 1);
430 
431 	tty_attach(tp);
432 
433 	if (ISSET(sc->sc_hwflags, PLCOM_HW_CONSOLE)) {
434 		int maj;
435 
436 		/* locate the major number */
437 		for (maj = 0; maj < nchrdev; maj++)
438 			if (cdevsw[maj].d_open == plcomopen)
439 				break;
440 
441 		cn_tab->cn_dev = makedev(maj, sc->sc_dev.dv_unit);
442 
443 		printf("%s: console\n", sc->sc_dev.dv_xname);
444 	}
445 
446 #ifdef KGDB
447 	/*
448 	 * Allow kgdb to "take over" this port.  If this is
449 	 * the kgdb device, it has exclusive use.
450 	 */
451 	if (iot == plcom_kgdb_iot && unit == plcom_kgdb_unit) {
452 		plcom_kgdb_attached = 1;
453 
454 		SET(sc->sc_hwflags, PLCOM_HW_KGDB);
455 		printf("%s: kgdb\n", sc->sc_dev.dv_xname);
456 	}
457 #endif
458 
459 #ifdef __HAVE_GENERIC_SOFT_INTERRUPTS
460 	sc->sc_si = softintr_establish(IPL_SOFTSERIAL, plcomsoft, sc);
461 #endif
462 
463 #if NRND > 0 && defined(RND_COM)
464 	rnd_attach_source(&sc->rnd_source, sc->sc_dev.dv_xname,
465 			  RND_TYPE_TTY, 0);
466 #endif
467 
468 	/* if there are no enable/disable functions, assume the device
469 	   is always enabled */
470 	if (!sc->enable)
471 		sc->enabled = 1;
472 
473 	plcom_config(sc);
474 
475 	SET(sc->sc_hwflags, PLCOM_HW_DEV_OK);
476 }
477 
478 void
479 plcom_config(struct plcom_softc *sc)
480 {
481 	bus_space_tag_t iot = sc->sc_iot;
482 	bus_space_handle_t ioh = sc->sc_ioh;
483 
484 	/* Disable interrupts before configuring the device. */
485 	sc->sc_cr = 0;
486 	bus_space_write_1(iot, ioh, plcom_cr, sc->sc_cr);
487 
488 	if (ISSET(sc->sc_hwflags, PLCOM_HW_CONSOLE|PLCOM_HW_KGDB))
489 		plcom_enable_debugport(sc);
490 }
491 
492 int
493 plcom_detach(self, flags)
494 	struct device *self;
495 	int flags;
496 {
497 	struct plcom_softc *sc = (struct plcom_softc *)self;
498 	int maj, mn;
499 
500 	/* locate the major number */
501 	for (maj = 0; maj < nchrdev; maj++)
502 		if (cdevsw[maj].d_open == plcomopen)
503 			break;
504 
505 	/* Nuke the vnodes for any open instances. */
506 	mn = self->dv_unit;
507 	vdevgone(maj, mn, mn, VCHR);
508 
509 	mn |= PLCOMDIALOUT_MASK;
510 	vdevgone(maj, mn, mn, VCHR);
511 
512 	/* Free the receive buffer. */
513 	free(sc->sc_rbuf, M_DEVBUF);
514 
515 	/* Detach and free the tty. */
516 	tty_detach(sc->sc_tty);
517 	ttyfree(sc->sc_tty);
518 
519 #ifdef __HAVE_GENERIC_SOFT_INTERRUPTS
520 	/* Unhook the soft interrupt handler. */
521 	softintr_disestablish(sc->sc_si);
522 #endif
523 
524 #if NRND > 0 && defined(RND_COM)
525 	/* Unhook the entropy source. */
526 	rnd_detach_source(&sc->rnd_source);
527 #endif
528 
529 	return 0;
530 }
531 
532 int
533 plcom_activate(struct device *self, enum devact act)
534 {
535 	struct plcom_softc *sc = (struct plcom_softc *)self;
536 	int s, rv = 0;
537 
538 	s = splserial();
539 	PLCOM_LOCK(sc);
540 	switch (act) {
541 	case DVACT_ACTIVATE:
542 		rv = EOPNOTSUPP;
543 		break;
544 
545 	case DVACT_DEACTIVATE:
546 		if (sc->sc_hwflags & (PLCOM_HW_CONSOLE|PLCOM_HW_KGDB)) {
547 			rv = EBUSY;
548 			break;
549 		}
550 
551 		if (sc->disable != NULL && sc->enabled != 0) {
552 			(*sc->disable)(sc);
553 			sc->enabled = 0;
554 		}
555 		break;
556 	}
557 
558 	PLCOM_UNLOCK(sc);
559 	splx(s);
560 	return rv;
561 }
562 
563 void
564 plcom_shutdown(struct plcom_softc *sc)
565 {
566 	struct tty *tp = sc->sc_tty;
567 	int s;
568 
569 	s = splserial();
570 	PLCOM_LOCK(sc);
571 
572 	/* If we were asserting flow control, then deassert it. */
573 	SET(sc->sc_rx_flags, RX_IBUF_BLOCKED);
574 	plcom_hwiflow(sc);
575 
576 	/* Clear any break condition set with TIOCSBRK. */
577 	plcom_break(sc, 0);
578 
579 	/* Turn off PPS capture on last close. */
580 	sc->sc_ppsmask = 0;
581 	sc->ppsparam.mode = 0;
582 
583 	/*
584 	 * Hang up if necessary.  Wait a bit, so the other side has time to
585 	 * notice even if we immediately open the port again.
586 	 * Avoid tsleeping above splhigh().
587 	 */
588 	if (ISSET(tp->t_cflag, HUPCL)) {
589 		plcom_modem(sc, 0);
590 		PLCOM_UNLOCK(sc);
591 		splx(s);
592 		/* XXX tsleep will only timeout */
593 		(void) tsleep(sc, TTIPRI, ttclos, hz);
594 		s = splserial();
595 		PLCOM_LOCK(sc);
596 	}
597 
598 	/* Turn off interrupts. */
599 	if (ISSET(sc->sc_hwflags, PLCOM_HW_CONSOLE))
600 		/* interrupt on break */
601 		sc->sc_cr = CR_RIE | CR_RTIE | CR_UARTEN;
602 	else
603 		sc->sc_cr = 0;
604 	bus_space_write_1(sc->sc_iot, sc->sc_ioh, plcom_cr, sc->sc_cr);
605 
606 	if (sc->disable) {
607 #ifdef DIAGNOSTIC
608 		if (!sc->enabled)
609 			panic("plcom_shutdown: not enabled?");
610 #endif
611 		(*sc->disable)(sc);
612 		sc->enabled = 0;
613 	}
614 	PLCOM_UNLOCK(sc);
615 	splx(s);
616 }
617 
618 int
619 plcomopen(dev_t dev, int flag, int mode, struct proc *p)
620 {
621 	struct plcom_softc *sc;
622 	struct tty *tp;
623 	int s, s2;
624 	int error;
625 
626 	sc = device_lookup(&plcom_cd, PLCOMUNIT(dev));
627 	if (sc == NULL || !ISSET(sc->sc_hwflags, PLCOM_HW_DEV_OK) ||
628 		sc->sc_rbuf == NULL)
629 		return ENXIO;
630 
631 	if (ISSET(sc->sc_dev.dv_flags, DVF_ACTIVE) == 0)
632 		return ENXIO;
633 
634 #ifdef KGDB
635 	/*
636 	 * If this is the kgdb port, no other use is permitted.
637 	 */
638 	if (ISSET(sc->sc_hwflags, PLCOM_HW_KGDB))
639 		return EBUSY;
640 #endif
641 
642 	tp = sc->sc_tty;
643 
644 	if (ISSET(tp->t_state, TS_ISOPEN) &&
645 	    ISSET(tp->t_state, TS_XCLUDE) &&
646 		p->p_ucred->cr_uid != 0)
647 		return EBUSY;
648 
649 	s = spltty();
650 
651 	/*
652 	 * Do the following iff this is a first open.
653 	 */
654 	if (!ISSET(tp->t_state, TS_ISOPEN) && tp->t_wopen == 0) {
655 		struct termios t;
656 
657 		tp->t_dev = dev;
658 
659 		s2 = splserial();
660 		PLCOM_LOCK(sc);
661 
662 		if (sc->enable) {
663 			if ((*sc->enable)(sc)) {
664 				PLCOM_UNLOCK(sc);
665 				splx(s2);
666 				splx(s);
667 				printf("%s: device enable failed\n",
668 				       sc->sc_dev.dv_xname);
669 				return EIO;
670 			}
671 			sc->enabled = 1;
672 			plcom_config(sc);
673 		}
674 
675 		/* Turn on interrupts. */
676 		/* IER_ERXRDY | IER_ERLS | IER_EMSC;  */
677 		sc->sc_cr = CR_RIE | CR_RTIE | CR_MSIE | CR_UARTEN;
678 		bus_space_write_1(sc->sc_iot, sc->sc_ioh, plcom_cr, sc->sc_cr);
679 
680 		/* Fetch the current modem control status, needed later. */
681 		sc->sc_msr = bus_space_read_1(sc->sc_iot, sc->sc_ioh, plcom_fr);
682 
683 		/* Clear PPS capture state on first open. */
684 		sc->sc_ppsmask = 0;
685 		sc->ppsparam.mode = 0;
686 
687 		PLCOM_UNLOCK(sc);
688 		splx(s2);
689 
690 		/*
691 		 * Initialize the termios status to the defaults.  Add in the
692 		 * sticky bits from TIOCSFLAGS.
693 		 */
694 		t.c_ispeed = 0;
695 		if (ISSET(sc->sc_hwflags, PLCOM_HW_CONSOLE)) {
696 			t.c_ospeed = plcomconsrate;
697 			t.c_cflag = plcomconscflag;
698 		} else {
699 			t.c_ospeed = TTYDEF_SPEED;
700 			t.c_cflag = TTYDEF_CFLAG;
701 		}
702 		if (ISSET(sc->sc_swflags, TIOCFLAG_CLOCAL))
703 			SET(t.c_cflag, CLOCAL);
704 		if (ISSET(sc->sc_swflags, TIOCFLAG_CRTSCTS))
705 			SET(t.c_cflag, CRTSCTS);
706 		if (ISSET(sc->sc_swflags, TIOCFLAG_MDMBUF))
707 			SET(t.c_cflag, MDMBUF);
708 		/* Make sure plcomparam() will do something. */
709 		tp->t_ospeed = 0;
710 		(void) plcomparam(tp, &t);
711 		tp->t_iflag = TTYDEF_IFLAG;
712 		tp->t_oflag = TTYDEF_OFLAG;
713 		tp->t_lflag = TTYDEF_LFLAG;
714 		ttychars(tp);
715 		ttsetwater(tp);
716 
717 		s2 = splserial();
718 		PLCOM_LOCK(sc);
719 
720 		/*
721 		 * Turn on DTR.  We must always do this, even if carrier is not
722 		 * present, because otherwise we'd have to use TIOCSDTR
723 		 * immediately after setting CLOCAL, which applications do not
724 		 * expect.  We always assert DTR while the device is open
725 		 * unless explicitly requested to deassert it.
726 		 */
727 		plcom_modem(sc, 1);
728 
729 		/* Clear the input ring, and unblock. */
730 		sc->sc_rbput = sc->sc_rbget = sc->sc_rbuf;
731 		sc->sc_rbavail = plcom_rbuf_size;
732 		plcom_iflush(sc);
733 		CLR(sc->sc_rx_flags, RX_ANY_BLOCK);
734 		plcom_hwiflow(sc);
735 
736 #ifdef PLCOM_DEBUG
737 		if (plcom_debug)
738 			plcomstatus(sc, "plcomopen  ");
739 #endif
740 
741 		PLCOM_UNLOCK(sc);
742 		splx(s2);
743 	}
744 
745 	splx(s);
746 
747 	error = ttyopen(tp, PLCOMDIALOUT(dev), ISSET(flag, O_NONBLOCK));
748 	if (error)
749 		goto bad;
750 
751 	error = (*tp->t_linesw->l_open)(dev, tp);
752 	if (error)
753 		goto bad;
754 
755 	return 0;
756 
757 bad:
758 	if (!ISSET(tp->t_state, TS_ISOPEN) && tp->t_wopen == 0) {
759 		/*
760 		 * We failed to open the device, and nobody else had it opened.
761 		 * Clean up the state as appropriate.
762 		 */
763 		plcom_shutdown(sc);
764 	}
765 
766 	return error;
767 }
768 
769 int
770 plcomclose(dev_t dev, int flag, int mode, struct proc *p)
771 {
772 	struct plcom_softc *sc = device_lookup(&plcom_cd, PLCOMUNIT(dev));
773 	struct tty *tp = sc->sc_tty;
774 
775 	/* XXX This is for cons.c. */
776 	if (!ISSET(tp->t_state, TS_ISOPEN))
777 		return 0;
778 
779 	(*tp->t_linesw->l_close)(tp, flag);
780 	ttyclose(tp);
781 
782 	if (PLCOM_ISALIVE(sc) == 0)
783 		return 0;
784 
785 	if (!ISSET(tp->t_state, TS_ISOPEN) && tp->t_wopen == 0) {
786 		/*
787 		 * Although we got a last close, the device may still be in
788 		 * use; e.g. if this was the dialout node, and there are still
789 		 * processes waiting for carrier on the non-dialout node.
790 		 */
791 		plcom_shutdown(sc);
792 	}
793 
794 	return 0;
795 }
796 
797 int
798 plcomread(dev_t dev, struct uio *uio, int flag)
799 {
800 	struct plcom_softc *sc = device_lookup(&plcom_cd, PLCOMUNIT(dev));
801 	struct tty *tp = sc->sc_tty;
802 
803 	if (PLCOM_ISALIVE(sc) == 0)
804 		return EIO;
805 
806 	return (*tp->t_linesw->l_read)(tp, uio, flag);
807 }
808 
809 int
810 plcomwrite(dev_t dev, struct uio *uio, int flag)
811 {
812 	struct plcom_softc *sc = device_lookup(&plcom_cd, PLCOMUNIT(dev));
813 	struct tty *tp = sc->sc_tty;
814 
815 	if (PLCOM_ISALIVE(sc) == 0)
816 		return EIO;
817 
818 	return (*tp->t_linesw->l_write)(tp, uio, flag);
819 }
820 
821 int
822 plcompoll(dev_t dev, int events, struct proc *p)
823 {
824 	struct plcom_softc *sc = device_lookup(&plcom_cd, PLCOMUNIT(dev));
825 	struct tty *tp = sc->sc_tty;
826 
827 	if (PLCOM_ISALIVE(sc) == 0)
828 		return EIO;
829 
830 	return (*tp->t_linesw->l_poll)(tp, events, p);
831 }
832 
833 struct tty *
834 plcomtty(dev_t dev)
835 {
836 	struct plcom_softc *sc = device_lookup(&plcom_cd, PLCOMUNIT(dev));
837 	struct tty *tp = sc->sc_tty;
838 
839 	return tp;
840 }
841 
842 int
843 plcomioctl(dev_t dev, u_long cmd, caddr_t data, int flag, struct proc *p)
844 {
845 	struct plcom_softc *sc = device_lookup(&plcom_cd, PLCOMUNIT(dev));
846 	struct tty *tp = sc->sc_tty;
847 	int error;
848 	int s;
849 
850 	if (PLCOM_ISALIVE(sc) == 0)
851 		return EIO;
852 
853 	error = (*tp->t_linesw->l_ioctl)(tp, cmd, data, flag, p);
854 	if (error != EPASSTHROUGH)
855 		return error;
856 
857 	error = ttioctl(tp, cmd, data, flag, p);
858 	if (error != EPASSTHROUGH)
859 		return error;
860 
861 	error = 0;
862 
863 	s = splserial();
864 	PLCOM_LOCK(sc);
865 
866 	switch (cmd) {
867 	case TIOCSBRK:
868 		plcom_break(sc, 1);
869 		break;
870 
871 	case TIOCCBRK:
872 		plcom_break(sc, 0);
873 		break;
874 
875 	case TIOCSDTR:
876 		plcom_modem(sc, 1);
877 		break;
878 
879 	case TIOCCDTR:
880 		plcom_modem(sc, 0);
881 		break;
882 
883 	case TIOCGFLAGS:
884 		*(int *)data = sc->sc_swflags;
885 		break;
886 
887 	case TIOCSFLAGS:
888 		error = suser(p->p_ucred, &p->p_acflag);
889 		if (error)
890 			break;
891 		sc->sc_swflags = *(int *)data;
892 		break;
893 
894 	case TIOCMSET:
895 	case TIOCMBIS:
896 	case TIOCMBIC:
897 		tiocm_to_plcom(sc, cmd, *(int *)data);
898 		break;
899 
900 	case TIOCMGET:
901 		*(int *)data = plcom_to_tiocm(sc);
902 		break;
903 
904 	case PPS_IOC_CREATE:
905 		break;
906 
907 	case PPS_IOC_DESTROY:
908 		break;
909 
910 	case PPS_IOC_GETPARAMS: {
911 		pps_params_t *pp;
912 		pp = (pps_params_t *)data;
913 		*pp = sc->ppsparam;
914 		break;
915 	}
916 
917 	case PPS_IOC_SETPARAMS: {
918 	  	pps_params_t *pp;
919 		int mode;
920 		pp = (pps_params_t *)data;
921 		if (pp->mode & ~ppscap) {
922 			error = EINVAL;
923 			break;
924 		}
925 		sc->ppsparam = *pp;
926 	 	/*
927 		 * Compute msr masks from user-specified timestamp state.
928 		 */
929 		mode = sc->ppsparam.mode;
930 #ifdef	PPS_SYNC
931 		if (mode & PPS_HARDPPSONASSERT) {
932 			mode |= PPS_CAPTUREASSERT;
933 			/* XXX revoke any previous HARDPPS source */
934 		}
935 		if (mode & PPS_HARDPPSONCLEAR) {
936 			mode |= PPS_CAPTURECLEAR;
937 			/* XXX revoke any previous HARDPPS source */
938 		}
939 #endif	/* PPS_SYNC */
940 		switch (mode & PPS_CAPTUREBOTH) {
941 		case 0:
942 			sc->sc_ppsmask = 0;
943 			break;
944 
945 		case PPS_CAPTUREASSERT:
946 			sc->sc_ppsmask = MSR_DCD;
947 			sc->sc_ppsassert = MSR_DCD;
948 			sc->sc_ppsclear = -1;
949 			break;
950 
951 		case PPS_CAPTURECLEAR:
952 			sc->sc_ppsmask = MSR_DCD;
953 			sc->sc_ppsassert = -1;
954 			sc->sc_ppsclear = 0;
955 			break;
956 
957 		case PPS_CAPTUREBOTH:
958 			sc->sc_ppsmask = MSR_DCD;
959 			sc->sc_ppsassert = MSR_DCD;
960 			sc->sc_ppsclear = 0;
961 			break;
962 
963 		default:
964 			error = EINVAL;
965 			break;
966 		}
967 		break;
968 	}
969 
970 	case PPS_IOC_GETCAP:
971 		*(int*)data = ppscap;
972 		break;
973 
974 	case PPS_IOC_FETCH: {
975 		pps_info_t *pi;
976 		pi = (pps_info_t *)data;
977 		*pi = sc->ppsinfo;
978 		break;
979 	}
980 
981 	case TIOCDCDTIMESTAMP:	/* XXX old, overloaded  API used by xntpd v3 */
982 		/*
983 		 * Some GPS clocks models use the falling rather than
984 		 * rising edge as the on-the-second signal.
985 		 * The old API has no way to specify PPS polarity.
986 		 */
987 		sc->sc_ppsmask = MSR_DCD;
988 #ifndef PPS_TRAILING_EDGE
989 		sc->sc_ppsassert = MSR_DCD;
990 		sc->sc_ppsclear = -1;
991 		TIMESPEC_TO_TIMEVAL((struct timeval *)data,
992 		    &sc->ppsinfo.assert_timestamp);
993 #else
994 		sc->sc_ppsassert = -1
995 		sc->sc_ppsclear = 0;
996 		TIMESPEC_TO_TIMEVAL((struct timeval *)data,
997 		    &sc->ppsinfo.clear_timestamp);
998 #endif
999 		break;
1000 
1001 	default:
1002 		error = EPASSTHROUGH;
1003 		break;
1004 	}
1005 
1006 	PLCOM_UNLOCK(sc);
1007 	splx(s);
1008 
1009 #ifdef PLCOM_DEBUG
1010 	if (plcom_debug)
1011 		plcomstatus(sc, "plcomioctl ");
1012 #endif
1013 
1014 	return error;
1015 }
1016 
1017 integrate void
1018 plcom_schedrx(struct plcom_softc *sc)
1019 {
1020 
1021 	sc->sc_rx_ready = 1;
1022 
1023 	/* Wake up the poller. */
1024 #ifdef __HAVE_GENERIC_SOFT_INTERRUPTS
1025 	softintr_schedule(sc->sc_si);
1026 #else
1027 #ifndef __NO_SOFT_SERIAL_INTERRUPT
1028 	setsoftserial();
1029 #else
1030 	if (!plcom_softintr_scheduled) {
1031 		plcom_softintr_scheduled = 1;
1032 		callout_reset(&plcomsoft_callout, 1, plcomsoft, NULL);
1033 	}
1034 #endif
1035 #endif
1036 }
1037 
1038 void
1039 plcom_break(struct plcom_softc *sc, int onoff)
1040 {
1041 
1042 	if (onoff)
1043 		SET(sc->sc_lcr, LCR_BRK);
1044 	else
1045 		CLR(sc->sc_lcr, LCR_BRK);
1046 
1047 	if (!sc->sc_heldchange) {
1048 		if (sc->sc_tx_busy) {
1049 			sc->sc_heldtbc = sc->sc_tbc;
1050 			sc->sc_tbc = 0;
1051 			sc->sc_heldchange = 1;
1052 		} else
1053 			plcom_loadchannelregs(sc);
1054 	}
1055 }
1056 
1057 void
1058 plcom_modem(struct plcom_softc *sc, int onoff)
1059 {
1060 
1061 	if (sc->sc_mcr_dtr == 0)
1062 		return;
1063 
1064 	if (onoff)
1065 		SET(sc->sc_mcr, sc->sc_mcr_dtr);
1066 	else
1067 		CLR(sc->sc_mcr, sc->sc_mcr_dtr);
1068 
1069 	if (!sc->sc_heldchange) {
1070 		if (sc->sc_tx_busy) {
1071 			sc->sc_heldtbc = sc->sc_tbc;
1072 			sc->sc_tbc = 0;
1073 			sc->sc_heldchange = 1;
1074 		} else
1075 			plcom_loadchannelregs(sc);
1076 	}
1077 }
1078 
1079 void
1080 tiocm_to_plcom(struct plcom_softc *sc, u_long how, int ttybits)
1081 {
1082 	u_char plcombits;
1083 
1084 	plcombits = 0;
1085 	if (ISSET(ttybits, TIOCM_DTR))
1086 		SET(plcombits, MCR_DTR);
1087 	if (ISSET(ttybits, TIOCM_RTS))
1088 		SET(plcombits, MCR_RTS);
1089 
1090 	switch (how) {
1091 	case TIOCMBIC:
1092 		CLR(sc->sc_mcr, plcombits);
1093 		break;
1094 
1095 	case TIOCMBIS:
1096 		SET(sc->sc_mcr, plcombits);
1097 		break;
1098 
1099 	case TIOCMSET:
1100 		CLR(sc->sc_mcr, MCR_DTR | MCR_RTS);
1101 		SET(sc->sc_mcr, plcombits);
1102 		break;
1103 	}
1104 
1105 	if (!sc->sc_heldchange) {
1106 		if (sc->sc_tx_busy) {
1107 			sc->sc_heldtbc = sc->sc_tbc;
1108 			sc->sc_tbc = 0;
1109 			sc->sc_heldchange = 1;
1110 		} else
1111 			plcom_loadchannelregs(sc);
1112 	}
1113 }
1114 
1115 int
1116 plcom_to_tiocm(struct plcom_softc *sc)
1117 {
1118 	u_char plcombits;
1119 	int ttybits = 0;
1120 
1121 	plcombits = sc->sc_mcr;
1122 	if (ISSET(plcombits, MCR_DTR))
1123 		SET(ttybits, TIOCM_DTR);
1124 	if (ISSET(plcombits, MCR_RTS))
1125 		SET(ttybits, TIOCM_RTS);
1126 
1127 	plcombits = sc->sc_msr;
1128 	if (ISSET(plcombits, MSR_DCD))
1129 		SET(ttybits, TIOCM_CD);
1130 	if (ISSET(plcombits, MSR_CTS))
1131 		SET(ttybits, TIOCM_CTS);
1132 	if (ISSET(plcombits, MSR_DSR))
1133 		SET(ttybits, TIOCM_DSR);
1134 
1135 	if (sc->sc_cr != 0)
1136 		SET(ttybits, TIOCM_LE);
1137 
1138 	return ttybits;
1139 }
1140 
1141 static u_char
1142 cflag2lcr(tcflag_t cflag)
1143 {
1144 	u_char lcr = 0;
1145 
1146 	switch (ISSET(cflag, CSIZE)) {
1147 	case CS5:
1148 		SET(lcr, LCR_5BITS);
1149 		break;
1150 	case CS6:
1151 		SET(lcr, LCR_6BITS);
1152 		break;
1153 	case CS7:
1154 		SET(lcr, LCR_7BITS);
1155 		break;
1156 	case CS8:
1157 		SET(lcr, LCR_8BITS);
1158 		break;
1159 	}
1160 	if (ISSET(cflag, PARENB)) {
1161 		SET(lcr, LCR_PEN);
1162 		if (!ISSET(cflag, PARODD))
1163 			SET(lcr, LCR_EPS);
1164 	}
1165 	if (ISSET(cflag, CSTOPB))
1166 		SET(lcr, LCR_STP2);
1167 
1168 	return lcr;
1169 }
1170 
1171 int
1172 plcomparam(struct tty *tp, struct termios *t)
1173 {
1174 	struct plcom_softc *sc = device_lookup(&plcom_cd, PLCOMUNIT(tp->t_dev));
1175 	int ospeed;
1176 	u_char lcr;
1177 	int s;
1178 
1179 	if (PLCOM_ISALIVE(sc) == 0)
1180 		return EIO;
1181 
1182 	ospeed = plcomspeed(t->c_ospeed, sc->sc_frequency);
1183 
1184 	/* Check requested parameters. */
1185 	if (ospeed < 0)
1186 		return EINVAL;
1187 	if (t->c_ispeed && t->c_ispeed != t->c_ospeed)
1188 		return EINVAL;
1189 
1190 	/*
1191 	 * For the console, always force CLOCAL and !HUPCL, so that the port
1192 	 * is always active.
1193 	 */
1194 	if (ISSET(sc->sc_swflags, TIOCFLAG_SOFTCAR) ||
1195 	    ISSET(sc->sc_hwflags, PLCOM_HW_CONSOLE)) {
1196 		SET(t->c_cflag, CLOCAL);
1197 		CLR(t->c_cflag, HUPCL);
1198 	}
1199 
1200 	/*
1201 	 * If there were no changes, don't do anything.  This avoids dropping
1202 	 * input and improves performance when all we did was frob things like
1203 	 * VMIN and VTIME.
1204 	 */
1205 	if (tp->t_ospeed == t->c_ospeed &&
1206 	    tp->t_cflag == t->c_cflag)
1207 		return 0;
1208 
1209 	lcr = ISSET(sc->sc_lcr, LCR_BRK) | cflag2lcr(t->c_cflag);
1210 
1211 	s = splserial();
1212 	PLCOM_LOCK(sc);
1213 
1214 	sc->sc_lcr = lcr;
1215 
1216 	/*
1217 	 * PL010 has a fixed-length FIFO trigger point.
1218 	 */
1219 	if (ISSET(sc->sc_hwflags, PLCOM_HW_FIFO))
1220 		sc->sc_fifo = 1;
1221 	else
1222 		sc->sc_fifo = 0;
1223 
1224 	if (sc->sc_fifo)
1225 		SET(sc->sc_lcr, LCR_FEN);
1226 
1227 	/*
1228 	 * If we're not in a mode that assumes a connection is present, then
1229 	 * ignore carrier changes.
1230 	 */
1231 	if (ISSET(t->c_cflag, CLOCAL | MDMBUF))
1232 		sc->sc_msr_dcd = 0;
1233 	else
1234 		sc->sc_msr_dcd = MSR_DCD;
1235 	/*
1236 	 * Set the flow control pins depending on the current flow control
1237 	 * mode.
1238 	 */
1239 	if (ISSET(t->c_cflag, CRTSCTS)) {
1240 		sc->sc_mcr_dtr = MCR_DTR;
1241 		sc->sc_mcr_rts = MCR_RTS;
1242 		sc->sc_msr_cts = MSR_CTS;
1243 	} else if (ISSET(t->c_cflag, MDMBUF)) {
1244 		/*
1245 		 * For DTR/DCD flow control, make sure we don't toggle DTR for
1246 		 * carrier detection.
1247 		 */
1248 		sc->sc_mcr_dtr = 0;
1249 		sc->sc_mcr_rts = MCR_DTR;
1250 		sc->sc_msr_cts = MSR_DCD;
1251 	} else {
1252 		/*
1253 		 * If no flow control, then always set RTS.  This will make
1254 		 * the other side happy if it mistakenly thinks we're doing
1255 		 * RTS/CTS flow control.
1256 		 */
1257 		sc->sc_mcr_dtr = MCR_DTR | MCR_RTS;
1258 		sc->sc_mcr_rts = 0;
1259 		sc->sc_msr_cts = 0;
1260 		if (ISSET(sc->sc_mcr, MCR_DTR))
1261 			SET(sc->sc_mcr, MCR_RTS);
1262 		else
1263 			CLR(sc->sc_mcr, MCR_RTS);
1264 	}
1265 	sc->sc_msr_mask = sc->sc_msr_cts | sc->sc_msr_dcd;
1266 
1267 #if 0
1268 	if (ospeed == 0)
1269 		CLR(sc->sc_mcr, sc->sc_mcr_dtr);
1270 	else
1271 		SET(sc->sc_mcr, sc->sc_mcr_dtr);
1272 #endif
1273 
1274 	sc->sc_dlbl = ospeed;
1275 	sc->sc_dlbh = ospeed >> 8;
1276 
1277 	/* And copy to tty. */
1278 	tp->t_ispeed = 0;
1279 	tp->t_ospeed = t->c_ospeed;
1280 	tp->t_cflag = t->c_cflag;
1281 
1282 	if (!sc->sc_heldchange) {
1283 		if (sc->sc_tx_busy) {
1284 			sc->sc_heldtbc = sc->sc_tbc;
1285 			sc->sc_tbc = 0;
1286 			sc->sc_heldchange = 1;
1287 		} else
1288 			plcom_loadchannelregs(sc);
1289 	}
1290 
1291 	if (!ISSET(t->c_cflag, CHWFLOW)) {
1292 		/* Disable the high water mark. */
1293 		sc->sc_r_hiwat = 0;
1294 		sc->sc_r_lowat = 0;
1295 		if (ISSET(sc->sc_rx_flags, RX_TTY_OVERFLOWED)) {
1296 			CLR(sc->sc_rx_flags, RX_TTY_OVERFLOWED);
1297 			plcom_schedrx(sc);
1298 		}
1299 		if (ISSET(sc->sc_rx_flags, RX_TTY_BLOCKED|RX_IBUF_BLOCKED)) {
1300 			CLR(sc->sc_rx_flags, RX_TTY_BLOCKED|RX_IBUF_BLOCKED);
1301 			plcom_hwiflow(sc);
1302 		}
1303 	} else {
1304 		sc->sc_r_hiwat = plcom_rbuf_hiwat;
1305 		sc->sc_r_lowat = plcom_rbuf_lowat;
1306 	}
1307 
1308 	PLCOM_UNLOCK(sc);
1309 	splx(s);
1310 
1311 	/*
1312 	 * Update the tty layer's idea of the carrier bit, in case we changed
1313 	 * CLOCAL or MDMBUF.  We don't hang up here; we only do that by
1314 	 * explicit request.
1315 	 */
1316 	(void) (*tp->t_linesw->l_modem)(tp, ISSET(sc->sc_msr, MSR_DCD));
1317 
1318 #ifdef PLCOM_DEBUG
1319 	if (plcom_debug)
1320 		plcomstatus(sc, "plcomparam ");
1321 #endif
1322 
1323 	if (!ISSET(t->c_cflag, CHWFLOW)) {
1324 		if (sc->sc_tx_stopped) {
1325 			sc->sc_tx_stopped = 0;
1326 			plcomstart(tp);
1327 		}
1328 	}
1329 
1330 	return 0;
1331 }
1332 
1333 void
1334 plcom_iflush(struct plcom_softc *sc)
1335 {
1336 	bus_space_tag_t iot = sc->sc_iot;
1337 	bus_space_handle_t ioh = sc->sc_ioh;
1338 #ifdef DIAGNOSTIC
1339 	int reg;
1340 #endif
1341 	int timo;
1342 
1343 #ifdef DIAGNOSTIC
1344 	reg = 0xffff;
1345 #endif
1346 	timo = 50000;
1347 	/* flush any pending I/O */
1348 	while (! ISSET(bus_space_read_1(iot, ioh, plcom_fr), FR_RXFE)
1349 	    && --timo)
1350 #ifdef DIAGNOSTIC
1351 		reg =
1352 #else
1353 		    (void)
1354 #endif
1355 		    bus_space_read_1(iot, ioh, plcom_dr);
1356 #ifdef DIAGNOSTIC
1357 	if (!timo)
1358 		printf("%s: plcom_iflush timeout %02x\n", sc->sc_dev.dv_xname,
1359 		       reg);
1360 #endif
1361 }
1362 
1363 void
1364 plcom_loadchannelregs(struct plcom_softc *sc)
1365 {
1366 	bus_space_tag_t iot = sc->sc_iot;
1367 	bus_space_handle_t ioh = sc->sc_ioh;
1368 
1369 	/* XXXXX necessary? */
1370 	plcom_iflush(sc);
1371 
1372 	bus_space_write_1(iot, ioh, plcom_cr, 0);
1373 
1374 	bus_space_write_1(iot, ioh, plcom_dlbl, sc->sc_dlbl);
1375 	bus_space_write_1(iot, ioh, plcom_dlbh, sc->sc_dlbh);
1376 	bus_space_write_1(iot, ioh, plcom_lcr, sc->sc_lcr);
1377 	sc->sc_set_mcr(sc->sc_set_mcr_arg, sc->sc_dev.dv_unit,
1378 	    sc->sc_mcr_active = sc->sc_mcr);
1379 
1380 	bus_space_write_1(iot, ioh, plcom_cr, sc->sc_cr);
1381 }
1382 
1383 int
1384 plcomhwiflow(struct tty *tp, int block)
1385 {
1386 	struct plcom_softc *sc = device_lookup(&plcom_cd, PLCOMUNIT(tp->t_dev));
1387 	int s;
1388 
1389 	if (PLCOM_ISALIVE(sc) == 0)
1390 		return 0;
1391 
1392 	if (sc->sc_mcr_rts == 0)
1393 		return 0;
1394 
1395 	s = splserial();
1396 	PLCOM_LOCK(sc);
1397 
1398 	if (block) {
1399 		if (!ISSET(sc->sc_rx_flags, RX_TTY_BLOCKED)) {
1400 			SET(sc->sc_rx_flags, RX_TTY_BLOCKED);
1401 			plcom_hwiflow(sc);
1402 		}
1403 	} else {
1404 		if (ISSET(sc->sc_rx_flags, RX_TTY_OVERFLOWED)) {
1405 			CLR(sc->sc_rx_flags, RX_TTY_OVERFLOWED);
1406 			plcom_schedrx(sc);
1407 		}
1408 		if (ISSET(sc->sc_rx_flags, RX_TTY_BLOCKED)) {
1409 			CLR(sc->sc_rx_flags, RX_TTY_BLOCKED);
1410 			plcom_hwiflow(sc);
1411 		}
1412 	}
1413 
1414 	PLCOM_UNLOCK(sc);
1415 	splx(s);
1416 	return 1;
1417 }
1418 
1419 /*
1420  * (un)block input via hw flowcontrol
1421  */
1422 void
1423 plcom_hwiflow(struct plcom_softc *sc)
1424 {
1425 	if (sc->sc_mcr_rts == 0)
1426 		return;
1427 
1428 	if (ISSET(sc->sc_rx_flags, RX_ANY_BLOCK)) {
1429 		CLR(sc->sc_mcr, sc->sc_mcr_rts);
1430 		CLR(sc->sc_mcr_active, sc->sc_mcr_rts);
1431 	} else {
1432 		SET(sc->sc_mcr, sc->sc_mcr_rts);
1433 		SET(sc->sc_mcr_active, sc->sc_mcr_rts);
1434 	}
1435 	sc->sc_set_mcr(sc->sc_set_mcr_arg, sc->sc_dev.dv_unit,
1436 	    sc->sc_mcr_active);
1437 }
1438 
1439 
1440 void
1441 plcomstart(struct tty *tp)
1442 {
1443 	struct plcom_softc *sc = device_lookup(&plcom_cd, PLCOMUNIT(tp->t_dev));
1444 	bus_space_tag_t iot = sc->sc_iot;
1445 	bus_space_handle_t ioh = sc->sc_ioh;
1446 	int s;
1447 
1448 	if (PLCOM_ISALIVE(sc) == 0)
1449 		return;
1450 
1451 	s = spltty();
1452 	if (ISSET(tp->t_state, TS_BUSY | TS_TIMEOUT | TS_TTSTOP))
1453 		goto out;
1454 	if (sc->sc_tx_stopped)
1455 		goto out;
1456 
1457 	if (tp->t_outq.c_cc <= tp->t_lowat) {
1458 		if (ISSET(tp->t_state, TS_ASLEEP)) {
1459 			CLR(tp->t_state, TS_ASLEEP);
1460 			wakeup(&tp->t_outq);
1461 		}
1462 		selwakeup(&tp->t_wsel);
1463 		if (tp->t_outq.c_cc == 0)
1464 			goto out;
1465 	}
1466 
1467 	/* Grab the first contiguous region of buffer space. */
1468 	{
1469 		u_char *tba;
1470 		int tbc;
1471 
1472 		tba = tp->t_outq.c_cf;
1473 		tbc = ndqb(&tp->t_outq, 0);
1474 
1475 		(void)splserial();
1476 		PLCOM_LOCK(sc);
1477 
1478 		sc->sc_tba = tba;
1479 		sc->sc_tbc = tbc;
1480 	}
1481 
1482 	SET(tp->t_state, TS_BUSY);
1483 	sc->sc_tx_busy = 1;
1484 
1485 	/* Enable transmit completion interrupts if necessary. */
1486 	if (!ISSET(sc->sc_cr, CR_TIE)) {
1487 		SET(sc->sc_cr, CR_TIE);
1488 		bus_space_write_1(iot, ioh, plcom_cr, sc->sc_cr);
1489 	}
1490 
1491 	/* Output the first chunk of the contiguous buffer. */
1492 	{
1493 		int n;
1494 
1495 		n = sc->sc_tbc;
1496 		if (n > sc->sc_fifolen)
1497 			n = sc->sc_fifolen;
1498 		bus_space_write_multi_1(iot, ioh, plcom_dr, sc->sc_tba, n);
1499 		sc->sc_tbc -= n;
1500 		sc->sc_tba += n;
1501 	}
1502 	PLCOM_UNLOCK(sc);
1503 out:
1504 	splx(s);
1505 	return;
1506 }
1507 
1508 /*
1509  * Stop output on a line.
1510  */
1511 void
1512 plcomstop(struct tty *tp, int flag)
1513 {
1514 	struct plcom_softc *sc = device_lookup(&plcom_cd, PLCOMUNIT(tp->t_dev));
1515 	int s;
1516 
1517 	s = splserial();
1518 	PLCOM_LOCK(sc);
1519 	if (ISSET(tp->t_state, TS_BUSY)) {
1520 		/* Stop transmitting at the next chunk. */
1521 		sc->sc_tbc = 0;
1522 		sc->sc_heldtbc = 0;
1523 		if (!ISSET(tp->t_state, TS_TTSTOP))
1524 			SET(tp->t_state, TS_FLUSH);
1525 	}
1526 	PLCOM_UNLOCK(sc);
1527 	splx(s);
1528 }
1529 
1530 void
1531 plcomdiag(void *arg)
1532 {
1533 	struct plcom_softc *sc = arg;
1534 	int overflows, floods;
1535 	int s;
1536 
1537 	s = splserial();
1538 	PLCOM_LOCK(sc);
1539 	overflows = sc->sc_overflows;
1540 	sc->sc_overflows = 0;
1541 	floods = sc->sc_floods;
1542 	sc->sc_floods = 0;
1543 	sc->sc_errors = 0;
1544 	PLCOM_UNLOCK(sc);
1545 	splx(s);
1546 
1547 	log(LOG_WARNING, "%s: %d silo overflow%s, %d ibuf flood%s\n",
1548 	    sc->sc_dev.dv_xname,
1549 	    overflows, overflows == 1 ? "" : "s",
1550 	    floods, floods == 1 ? "" : "s");
1551 }
1552 
1553 integrate void
1554 plcom_rxsoft(struct plcom_softc *sc, struct tty *tp)
1555 {
1556 	int (*rint) (int, struct tty *) = tp->t_linesw->l_rint;
1557 	u_char *get, *end;
1558 	u_int cc, scc;
1559 	u_char rsr;
1560 	int code;
1561 	int s;
1562 
1563 	end = sc->sc_ebuf;
1564 	get = sc->sc_rbget;
1565 	scc = cc = plcom_rbuf_size - sc->sc_rbavail;
1566 
1567 	if (cc == plcom_rbuf_size) {
1568 		sc->sc_floods++;
1569 		if (sc->sc_errors++ == 0)
1570 			callout_reset(&sc->sc_diag_callout, 60 * hz,
1571 			    plcomdiag, sc);
1572 	}
1573 
1574 	while (cc) {
1575 		code = get[0];
1576 		rsr = get[1];
1577 		if (ISSET(rsr, RSR_OE | RSR_BE | RSR_FE | RSR_PE)) {
1578 			if (ISSET(rsr, RSR_OE)) {
1579 				sc->sc_overflows++;
1580 				if (sc->sc_errors++ == 0)
1581 					callout_reset(&sc->sc_diag_callout,
1582 					    60 * hz, plcomdiag, sc);
1583 			}
1584 			if (ISSET(rsr, RSR_BE | RSR_FE))
1585 				SET(code, TTY_FE);
1586 			if (ISSET(rsr, RSR_PE))
1587 				SET(code, TTY_PE);
1588 		}
1589 		if ((*rint)(code, tp) == -1) {
1590 			/*
1591 			 * The line discipline's buffer is out of space.
1592 			 */
1593 			if (!ISSET(sc->sc_rx_flags, RX_TTY_BLOCKED)) {
1594 				/*
1595 				 * We're either not using flow control, or the
1596 				 * line discipline didn't tell us to block for
1597 				 * some reason.  Either way, we have no way to
1598 				 * know when there's more space available, so
1599 				 * just drop the rest of the data.
1600 				 */
1601 				get += cc << 1;
1602 				if (get >= end)
1603 					get -= plcom_rbuf_size << 1;
1604 				cc = 0;
1605 			} else {
1606 				/*
1607 				 * Don't schedule any more receive processing
1608 				 * until the line discipline tells us there's
1609 				 * space available (through plcomhwiflow()).
1610 				 * Leave the rest of the data in the input
1611 				 * buffer.
1612 				 */
1613 				SET(sc->sc_rx_flags, RX_TTY_OVERFLOWED);
1614 			}
1615 			break;
1616 		}
1617 		get += 2;
1618 		if (get >= end)
1619 			get = sc->sc_rbuf;
1620 		cc--;
1621 	}
1622 
1623 	if (cc != scc) {
1624 		sc->sc_rbget = get;
1625 		s = splserial();
1626 		PLCOM_LOCK(sc);
1627 
1628 		cc = sc->sc_rbavail += scc - cc;
1629 		/* Buffers should be ok again, release possible block. */
1630 		if (cc >= sc->sc_r_lowat) {
1631 			if (ISSET(sc->sc_rx_flags, RX_IBUF_OVERFLOWED)) {
1632 				CLR(sc->sc_rx_flags, RX_IBUF_OVERFLOWED);
1633 				SET(sc->sc_cr, CR_RIE | CR_RTIE);
1634 				bus_space_write_1(sc->sc_iot, sc->sc_ioh, plcom_cr, sc->sc_cr);
1635 			}
1636 			if (ISSET(sc->sc_rx_flags, RX_IBUF_BLOCKED)) {
1637 				CLR(sc->sc_rx_flags, RX_IBUF_BLOCKED);
1638 				plcom_hwiflow(sc);
1639 			}
1640 		}
1641 		PLCOM_UNLOCK(sc);
1642 		splx(s);
1643 	}
1644 }
1645 
1646 integrate void
1647 plcom_txsoft(struct plcom_softc *sc, struct tty *tp)
1648 {
1649 
1650 	CLR(tp->t_state, TS_BUSY);
1651 	if (ISSET(tp->t_state, TS_FLUSH))
1652 		CLR(tp->t_state, TS_FLUSH);
1653 	else
1654 		ndflush(&tp->t_outq, (int)(sc->sc_tba - tp->t_outq.c_cf));
1655 	(*tp->t_linesw->l_start)(tp);
1656 }
1657 
1658 integrate void
1659 plcom_stsoft(struct plcom_softc *sc, struct tty *tp)
1660 {
1661 	u_char msr, delta;
1662 	int s;
1663 
1664 	s = splserial();
1665 	PLCOM_LOCK(sc);
1666 	msr = sc->sc_msr;
1667 	delta = sc->sc_msr_delta;
1668 	sc->sc_msr_delta = 0;
1669 	PLCOM_UNLOCK(sc);
1670 	splx(s);
1671 
1672 	if (ISSET(delta, sc->sc_msr_dcd)) {
1673 		/*
1674 		 * Inform the tty layer that carrier detect changed.
1675 		 */
1676 		(void) (*tp->t_linesw->l_modem)(tp, ISSET(msr, MSR_DCD));
1677 	}
1678 
1679 	if (ISSET(delta, sc->sc_msr_cts)) {
1680 		/* Block or unblock output according to flow control. */
1681 		if (ISSET(msr, sc->sc_msr_cts)) {
1682 			sc->sc_tx_stopped = 0;
1683 			(*tp->t_linesw->l_start)(tp);
1684 		} else {
1685 			sc->sc_tx_stopped = 1;
1686 		}
1687 	}
1688 
1689 #ifdef PLCOM_DEBUG
1690 	if (plcom_debug)
1691 		plcomstatus(sc, "plcom_stsoft");
1692 #endif
1693 }
1694 
1695 #ifdef __HAVE_GENERIC_SOFT_INTERRUPTS
1696 void
1697 plcomsoft(void *arg)
1698 {
1699 	struct plcom_softc *sc = arg;
1700 	struct tty *tp;
1701 
1702 	if (PLCOM_ISALIVE(sc) == 0)
1703 		return;
1704 
1705 	{
1706 #else
1707 void
1708 #ifndef __NO_SOFT_SERIAL_INTERRUPT
1709 plcomsoft(void)
1710 #else
1711 plcomsoft(void *arg)
1712 #endif
1713 {
1714 	struct plcom_softc	*sc;
1715 	struct tty	*tp;
1716 	int	unit;
1717 #ifdef __NO_SOFT_SERIAL_INTERRUPT
1718 	int s;
1719 
1720 	s = splsoftserial();
1721 	plcom_softintr_scheduled = 0;
1722 #endif
1723 
1724 	for (unit = 0; unit < plcom_cd.cd_ndevs; unit++) {
1725 		sc = device_lookup(&plcom_cd, unit);
1726 		if (sc == NULL || !ISSET(sc->sc_hwflags, PLCOM_HW_DEV_OK))
1727 			continue;
1728 
1729 		if (PLCOM_ISALIVE(sc) == 0)
1730 			continue;
1731 
1732 		tp = sc->sc_tty;
1733 		if (tp == NULL)
1734 			continue;
1735 		if (!ISSET(tp->t_state, TS_ISOPEN) && tp->t_wopen == 0)
1736 			continue;
1737 #endif
1738 		tp = sc->sc_tty;
1739 
1740 		if (sc->sc_rx_ready) {
1741 			sc->sc_rx_ready = 0;
1742 			plcom_rxsoft(sc, tp);
1743 		}
1744 
1745 		if (sc->sc_st_check) {
1746 			sc->sc_st_check = 0;
1747 			plcom_stsoft(sc, tp);
1748 		}
1749 
1750 		if (sc->sc_tx_done) {
1751 			sc->sc_tx_done = 0;
1752 			plcom_txsoft(sc, tp);
1753 		}
1754 	}
1755 
1756 #ifndef __HAVE_GENERIC_SOFT_INTERRUPTS
1757 #ifdef __NO_SOFT_SERIAL_INTERRUPT
1758 	splx(s);
1759 #endif
1760 #endif
1761 }
1762 
1763 #ifdef __ALIGN_BRACKET_LEVEL_FOR_CTAGS
1764 	/* there has got to be a better way to do plcomsoft() */
1765 }}
1766 #endif
1767 
1768 int
1769 plcomintr(void *arg)
1770 {
1771 	struct plcom_softc *sc = arg;
1772 	bus_space_tag_t iot = sc->sc_iot;
1773 	bus_space_handle_t ioh = sc->sc_ioh;
1774 	u_char *put, *end;
1775 	u_int cc;
1776 	u_char rsr, iir;
1777 
1778 	if (PLCOM_ISALIVE(sc) == 0)
1779 		return 0;
1780 
1781 	PLCOM_LOCK(sc);
1782 	iir = bus_space_read_1(iot, ioh, plcom_iir);
1783 	if (! ISSET(iir, IIR_IMASK)) {
1784 		PLCOM_UNLOCK(sc);
1785 		return 0;
1786 	}
1787 
1788 	end = sc->sc_ebuf;
1789 	put = sc->sc_rbput;
1790 	cc = sc->sc_rbavail;
1791 
1792 	do {
1793 		u_char	msr, delta, fr;
1794 
1795 		fr = bus_space_read_1(iot, ioh, plcom_fr);
1796 
1797 		if (!ISSET(fr, FR_RXFE) &&
1798 		    !ISSET(sc->sc_rx_flags, RX_IBUF_OVERFLOWED)) {
1799 			while (cc > 0) {
1800 				int cn_trapped = 0;
1801 				put[0] = bus_space_read_1(iot, ioh,
1802 				    plcom_dr);
1803 				rsr = bus_space_read_1(iot, ioh, plcom_rsr);
1804 				/* Clear any error status.  */
1805 				if (ISSET(rsr,
1806 				    (RSR_BE | RSR_OE | RSR_PE | RSR_FE)))
1807 					bus_space_write_1(iot, ioh, plcom_ecr,
1808 					    0);
1809 				if (ISSET(rsr, RSR_BE)) {
1810 					int cn_trapped = 0;
1811 					cn_check_magic(sc->sc_tty->t_dev,
1812 					    CNC_BREAK, plcom_cnm_state);
1813 					if (cn_trapped)
1814 						continue;
1815 #if defined(KGDB)
1816 					if (ISSET(sc->sc_hwflags,
1817 					    PLCOM_HW_KGDB)) {
1818 						kgdb_connect(1);
1819 						continue;
1820 					}
1821 #endif
1822 				}
1823 
1824 				put[1] = rsr;
1825 				cn_check_magic(sc->sc_tty->t_dev,
1826 					       put[0], plcom_cnm_state);
1827 				if (cn_trapped) {
1828 					fr = bus_space_read_1(iot, ioh,
1829 					    plcom_fr);
1830 					if (ISSET(fr, FR_RXFE))
1831 						break;
1832 
1833 					continue;
1834 				}
1835 				put += 2;
1836 				if (put >= end)
1837 					put = sc->sc_rbuf;
1838 				cc--;
1839 
1840 				fr = bus_space_read_1(iot, ioh, plcom_fr);
1841 				if (ISSET(fr, FR_RXFE))
1842 					break;
1843 			}
1844 
1845 			/*
1846 			 * Current string of incoming characters ended because
1847 			 * no more data was available or we ran out of space.
1848 			 * Schedule a receive event if any data was received.
1849 			 * If we're out of space, turn off receive interrupts.
1850 			 */
1851 			sc->sc_rbput = put;
1852 			sc->sc_rbavail = cc;
1853 			if (!ISSET(sc->sc_rx_flags, RX_TTY_OVERFLOWED))
1854 				sc->sc_rx_ready = 1;
1855 
1856 			/*
1857 			 * See if we are in danger of overflowing a buffer. If
1858 			 * so, use hardware flow control to ease the pressure.
1859 			 */
1860 			if (!ISSET(sc->sc_rx_flags, RX_IBUF_BLOCKED) &&
1861 			    cc < sc->sc_r_hiwat) {
1862 				SET(sc->sc_rx_flags, RX_IBUF_BLOCKED);
1863 				plcom_hwiflow(sc);
1864 			}
1865 
1866 			/*
1867 			 * If we're out of space, disable receive interrupts
1868 			 * until the queue has drained a bit.
1869 			 */
1870 			if (!cc) {
1871 				SET(sc->sc_rx_flags, RX_IBUF_OVERFLOWED);
1872 				CLR(sc->sc_cr, CR_RIE | CR_RTIE);
1873 				bus_space_write_1(iot, ioh, plcom_cr,
1874 				    sc->sc_cr);
1875 			}
1876 		} else {
1877 			if (ISSET(iir, IIR_RIS)) {
1878 				bus_space_write_1(iot, ioh, plcom_cr, 0);
1879 				delay(10);
1880 				bus_space_write_1(iot, ioh, plcom_cr,
1881 				    sc->sc_cr);
1882 				continue;
1883 			}
1884 		}
1885 
1886 		msr = bus_space_read_1(iot, ioh, plcom_fr);
1887 		delta = msr ^ sc->sc_msr;
1888 		sc->sc_msr = msr;
1889 		/* Clear any pending modem status interrupt.  */
1890 		if (iir & IIR_MIS)
1891 			bus_space_write_1(iot, ioh, plcom_icr, 0);
1892 		/*
1893 		 * Pulse-per-second (PSS) signals on edge of DCD?
1894 		 * Process these even if line discipline is ignoring DCD.
1895 		 */
1896 		if (delta & sc->sc_ppsmask) {
1897 			struct timeval tv;
1898 		    	if ((msr & sc->sc_ppsmask) == sc->sc_ppsassert) {
1899 				/* XXX nanotime() */
1900 				microtime(&tv);
1901 				TIMEVAL_TO_TIMESPEC(&tv,
1902 				    &sc->ppsinfo.assert_timestamp);
1903 				if (sc->ppsparam.mode & PPS_OFFSETASSERT) {
1904 					timespecadd(&sc->ppsinfo.assert_timestamp,
1905 					    &sc->ppsparam.assert_offset,
1906 						    &sc->ppsinfo.assert_timestamp);
1907 				}
1908 
1909 #ifdef PPS_SYNC
1910 				if (sc->ppsparam.mode & PPS_HARDPPSONASSERT)
1911 					hardpps(&tv, tv.tv_usec);
1912 #endif
1913 				sc->ppsinfo.assert_sequence++;
1914 				sc->ppsinfo.current_mode = sc->ppsparam.mode;
1915 
1916 			} else if ((msr & sc->sc_ppsmask) == sc->sc_ppsclear) {
1917 				/* XXX nanotime() */
1918 				microtime(&tv);
1919 				TIMEVAL_TO_TIMESPEC(&tv,
1920 				    &sc->ppsinfo.clear_timestamp);
1921 				if (sc->ppsparam.mode & PPS_OFFSETCLEAR) {
1922 					timespecadd(&sc->ppsinfo.clear_timestamp,
1923 					    &sc->ppsparam.clear_offset,
1924 					    &sc->ppsinfo.clear_timestamp);
1925 				}
1926 
1927 #ifdef PPS_SYNC
1928 				if (sc->ppsparam.mode & PPS_HARDPPSONCLEAR)
1929 					hardpps(&tv, tv.tv_usec);
1930 #endif
1931 				sc->ppsinfo.clear_sequence++;
1932 				sc->ppsinfo.current_mode = sc->ppsparam.mode;
1933 			}
1934 		}
1935 
1936 		/*
1937 		 * Process normal status changes
1938 		 */
1939 		if (ISSET(delta, sc->sc_msr_mask)) {
1940 			SET(sc->sc_msr_delta, delta);
1941 
1942 			/*
1943 			 * Stop output immediately if we lose the output
1944 			 * flow control signal or carrier detect.
1945 			 */
1946 			if (ISSET(~msr, sc->sc_msr_mask)) {
1947 				sc->sc_tbc = 0;
1948 				sc->sc_heldtbc = 0;
1949 #ifdef PLCOM_DEBUG
1950 				if (plcom_debug)
1951 					plcomstatus(sc, "plcomintr  ");
1952 #endif
1953 			}
1954 
1955 			sc->sc_st_check = 1;
1956 		}
1957 
1958 		/*
1959 		 * Done handling any receive interrupts. See if data
1960 		 * can be * transmitted as well. Schedule tx done
1961 		 * event if no data left * and tty was marked busy.
1962 		 */
1963 		if (ISSET(iir, IIR_TIS)) {
1964 			/*
1965 			 * If we've delayed a parameter change, do it
1966 			 * now, and restart * output.
1967 			 */
1968 			if (sc->sc_heldchange) {
1969 				plcom_loadchannelregs(sc);
1970 				sc->sc_heldchange = 0;
1971 				sc->sc_tbc = sc->sc_heldtbc;
1972 				sc->sc_heldtbc = 0;
1973 			}
1974 
1975 			/*
1976 			 * Output the next chunk of the contiguous
1977 			 * buffer, if any.
1978 			 */
1979 			if (sc->sc_tbc > 0) {
1980 				int n;
1981 
1982 				n = sc->sc_tbc;
1983 				if (n > sc->sc_fifolen)
1984 					n = sc->sc_fifolen;
1985 				bus_space_write_multi_1(iot, ioh, plcom_dr,
1986 				    sc->sc_tba, n);
1987 				sc->sc_tbc -= n;
1988 				sc->sc_tba += n;
1989 			} else {
1990 				/*
1991 				 * Disable transmit plcompletion
1992 				 * interrupts if necessary.
1993 				 */
1994 				if (ISSET(sc->sc_cr, CR_TIE)) {
1995 					CLR(sc->sc_cr, CR_TIE);
1996 					bus_space_write_1(iot, ioh, plcom_cr,
1997 					    sc->sc_cr);
1998 				}
1999 				if (sc->sc_tx_busy) {
2000 					sc->sc_tx_busy = 0;
2001 					sc->sc_tx_done = 1;
2002 				}
2003 			}
2004 		}
2005 	} while (ISSET((iir = bus_space_read_1(iot, ioh, plcom_iir)),
2006 	    IIR_IMASK));
2007 
2008 	PLCOM_UNLOCK(sc);
2009 
2010 	/* Wake up the poller. */
2011 #ifdef __HAVE_GENERIC_SOFT_INTERRUPTS
2012 	softintr_schedule(sc->sc_si);
2013 #else
2014 #ifndef __NO_SOFT_SERIAL_INTERRUPT
2015 	setsoftserial();
2016 #else
2017 	if (!plcom_softintr_scheduled) {
2018 		plcom_softintr_scheduled = 1;
2019 		callout_reset(&plcomsoft_callout, 1, plcomsoft, NULL);
2020 	}
2021 #endif
2022 #endif
2023 
2024 #if NRND > 0 && defined(RND_COM)
2025 	rnd_add_uint32(&sc->rnd_source, iir | rsr);
2026 #endif
2027 
2028 	return 1;
2029 }
2030 
2031 /*
2032  * The following functions are polled getc and putc routines, shared
2033  * by the console and kgdb glue.
2034  *
2035  * The read-ahead code is so that you can detect pending in-band
2036  * cn_magic in polled mode while doing output rather than having to
2037  * wait until the kernel decides it needs input.
2038  */
2039 
2040 #define MAX_READAHEAD	20
2041 static int plcom_readahead[MAX_READAHEAD];
2042 static int plcom_readaheadcount = 0;
2043 
2044 int
2045 plcom_common_getc(dev_t dev, bus_space_tag_t iot, bus_space_handle_t ioh)
2046 {
2047 	int s = splserial();
2048 	u_char stat, c;
2049 
2050 	/* got a character from reading things earlier */
2051 	if (plcom_readaheadcount > 0) {
2052 		int i;
2053 
2054 		c = plcom_readahead[0];
2055 		for (i = 1; i < plcom_readaheadcount; i++) {
2056 			plcom_readahead[i-1] = plcom_readahead[i];
2057 		}
2058 		plcom_readaheadcount--;
2059 		splx(s);
2060 		return c;
2061 	}
2062 
2063 	/* block until a character becomes available */
2064 	while (ISSET(stat = bus_space_read_1(iot, ioh, plcom_fr), FR_RXFE))
2065 		;
2066 
2067 	c = bus_space_read_1(iot, ioh, plcom_dr);
2068 	stat = bus_space_read_1(iot, ioh, plcom_iir);
2069 	{
2070 		int cn_trapped = 0; /* unused */
2071 #ifdef DDB
2072 		extern int db_active;
2073 		if (!db_active)
2074 #endif
2075 			cn_check_magic(dev, c, plcom_cnm_state);
2076 	}
2077 	splx(s);
2078 	return c;
2079 }
2080 
2081 void
2082 plcom_common_putc(dev_t dev, bus_space_tag_t iot, bus_space_handle_t ioh,
2083     int c)
2084 {
2085 	int s = splserial();
2086 	int timo;
2087 
2088 	int cin, stat;
2089 	if (plcom_readaheadcount < MAX_READAHEAD
2090 	     && !ISSET(stat = bus_space_read_1(iot, ioh, plcom_fr), FR_RXFE)) {
2091 		int cn_trapped = 0;
2092 		cin = bus_space_read_1(iot, ioh, plcom_dr);
2093 		stat = bus_space_read_1(iot, ioh, plcom_iir);
2094 		cn_check_magic(dev, cin, plcom_cnm_state);
2095 		plcom_readahead[plcom_readaheadcount++] = cin;
2096 	}
2097 
2098 	/* wait for any pending transmission to finish */
2099 	timo = 150000;
2100 	while (!ISSET(bus_space_read_1(iot, ioh, plcom_fr), FR_TXFE) && --timo)
2101 		continue;
2102 
2103 	bus_space_write_1(iot, ioh, plcom_dr, c);
2104 	PLCOM_BARRIER(iot, ioh, BR | BW);
2105 
2106 	/* wait for this transmission to complete */
2107 	timo = 1500000;
2108 	while (!ISSET(bus_space_read_1(iot, ioh, plcom_fr), FR_TXFE) && --timo)
2109 		continue;
2110 
2111 	splx(s);
2112 }
2113 
2114 /*
2115  * Initialize UART for use as console or KGDB line.
2116  */
2117 int
2118 plcominit(bus_space_tag_t iot, bus_addr_t iobase, int rate, int frequency,
2119     tcflag_t cflag, bus_space_handle_t *iohp)
2120 {
2121 	bus_space_handle_t ioh;
2122 
2123 	if (bus_space_map(iot, iobase, PLCOM_UART_SIZE, 0, &ioh))
2124 		return ENOMEM; /* ??? */
2125 
2126 	rate = plcomspeed(rate, frequency);
2127 	bus_space_write_1(iot, ioh, plcom_cr, 0);
2128 	bus_space_write_1(iot, ioh, plcom_dlbl, rate);
2129 	bus_space_write_1(iot, ioh, plcom_dlbh, rate >> 8);
2130 	bus_space_write_1(iot, ioh, plcom_lcr, cflag2lcr(cflag) | LCR_FEN);
2131 	bus_space_write_1(iot, ioh, plcom_cr, CR_UARTEN);
2132 
2133 #if 0
2134 	/* Ought to do something like this, but we have no sc to
2135 	   dereference. */
2136 	sc->sc_set_mcr(sc->sc_set_mcr_arg, sc->sc_dev.dv_unit,
2137 	    MCR_DTR | MCR_RTS);
2138 #endif
2139 
2140 	*iohp = ioh;
2141 	return 0;
2142 }
2143 
2144 /*
2145  * Following are all routines needed for PLCOM to act as console
2146  */
2147 struct consdev plcomcons = {
2148 	NULL, NULL, plcomcngetc, plcomcnputc, plcomcnpollc, NULL,
2149 	NODEV, CN_NORMAL
2150 };
2151 
2152 
2153 int
2154 plcomcnattach(bus_space_tag_t iot, bus_addr_t iobase, int rate, int frequency,
2155     tcflag_t cflag, int unit)
2156 {
2157 	int res;
2158 
2159 	res = plcominit(iot, iobase, rate, frequency, cflag, &plcomconsioh);
2160 	if (res)
2161 		return res;
2162 
2163 	cn_tab = &plcomcons;
2164 	cn_init_magic(&plcom_cnm_state);
2165 	cn_set_magic("\047\001"); /* default magic is BREAK */
2166 
2167 	plcomconstag = iot;
2168 	plcomconsunit = unit;
2169 	plcomconsrate = rate;
2170 	plcomconscflag = cflag;
2171 
2172 	return 0;
2173 }
2174 
2175 void
2176 plcomcndetach(void)
2177 {
2178 	bus_space_unmap(plcomconstag, plcomconsioh, PLCOM_UART_SIZE);
2179 	plcomconstag = NULL;
2180 
2181 	cn_tab = NULL;
2182 }
2183 
2184 int
2185 plcomcngetc(dev_t dev)
2186 {
2187 	return plcom_common_getc(dev, plcomconstag, plcomconsioh);
2188 }
2189 
2190 /*
2191  * Console kernel output character routine.
2192  */
2193 void
2194 plcomcnputc(dev_t dev, int c)
2195 {
2196 	plcom_common_putc(dev, plcomconstag, plcomconsioh, c);
2197 }
2198 
2199 void
2200 plcomcnpollc(dev_t dev, int on)
2201 {
2202 
2203 }
2204 
2205 #ifdef KGDB
2206 int
2207 plcom_kgdb_attach(bus_space_tag_t iot, bus_addr_t iobase, int rate,
2208    int frequency, tcflag_t cflag, int unit)
2209 {
2210 	int res;
2211 
2212 	if (iot == plcomconstag && iobase == plcomconsunit)
2213 		return EBUSY; /* cannot share with console */
2214 
2215 	res = plcominit(iot, iobase, rate, frequency, cflag, &plcom_kgdb_ioh);
2216 	if (res)
2217 		return res;
2218 
2219 	kgdb_attach(plcom_kgdb_getc, plcom_kgdb_putc, NULL);
2220 	kgdb_dev = 123; /* unneeded, only to satisfy some tests */
2221 
2222 	plcom_kgdb_iot = iot;
2223 	plcom_kgdb_unit = unit;
2224 
2225 	return 0;
2226 }
2227 
2228 /* ARGSUSED */
2229 int
2230 plcom_kgdb_getc(void *arg)
2231 {
2232 	return plcom_common_getc(NODEV, plcom_kgdb_iot, plcom_kgdb_ioh);
2233 }
2234 
2235 /* ARGSUSED */
2236 void
2237 plcom_kgdb_putc(void *arg, int c)
2238 {
2239 	plcom_common_putc(NODEV, plcom_kgdb_iot, plcom_kgdb_ioh, c);
2240 }
2241 #endif /* KGDB */
2242 
2243 /* helper function to identify the plcom ports used by
2244  console or KGDB (and not yet autoconf attached) */
2245 int
2246 plcom_is_console(bus_space_tag_t iot, int unit,
2247     bus_space_handle_t *ioh)
2248 {
2249 	bus_space_handle_t help;
2250 
2251 	if (!plcomconsattached &&
2252 	    iot == plcomconstag && unit == plcomconsunit)
2253 		help = plcomconsioh;
2254 #ifdef KGDB
2255 	else if (!plcom_kgdb_attached &&
2256 	    iot == plcom_kgdb_iot && unit == plcom_kgdb_unit)
2257 		help = plcom_kgdb_ioh;
2258 #endif
2259 	else
2260 		return 0;
2261 
2262 	if (ioh)
2263 		*ioh = help;
2264 	return 1;
2265 }
2266