xref: /netbsd-src/sys/dev/ic/com.c (revision e5548b402ae4c44fb816de42c7bba9581ce23ef5)
1 /*	$NetBSD: com.c,v 1.238 2005/12/11 12:21:26 christos Exp $	*/
2 
3 /*-
4  * Copyright (c) 1998, 1999, 2004 The NetBSD Foundation, Inc.
5  * All rights reserved.
6  *
7  * This code is derived from software contributed to The NetBSD Foundation
8  * by Charles M. Hannum.
9  *
10  * Redistribution and use in source and binary forms, with or without
11  * modification, are permitted provided that the following conditions
12  * are met:
13  * 1. Redistributions of source code must retain the above copyright
14  *    notice, this list of conditions and the following disclaimer.
15  * 2. Redistributions in binary form must reproduce the above copyright
16  *    notice, this list of conditions and the following disclaimer in the
17  *    documentation and/or other materials provided with the distribution.
18  * 3. All advertising materials mentioning features or use of this software
19  *    must display the following acknowledgement:
20  *        This product includes software developed by the NetBSD
21  *        Foundation, Inc. and its contributors.
22  * 4. Neither the name of The NetBSD Foundation nor the names of its
23  *    contributors may be used to endorse or promote products derived
24  *    from this software without specific prior written permission.
25  *
26  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
27  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
28  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
29  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
30  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
31  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
32  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
33  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
34  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
35  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
36  * POSSIBILITY OF SUCH DAMAGE.
37  */
38 
39 /*
40  * Copyright (c) 1991 The Regents of the University of California.
41  * All rights reserved.
42  *
43  * Redistribution and use in source and binary forms, with or without
44  * modification, are permitted provided that the following conditions
45  * are met:
46  * 1. Redistributions of source code must retain the above copyright
47  *    notice, this list of conditions and the following disclaimer.
48  * 2. Redistributions in binary form must reproduce the above copyright
49  *    notice, this list of conditions and the following disclaimer in the
50  *    documentation and/or other materials provided with the distribution.
51  * 3. Neither the name of the University nor the names of its contributors
52  *    may be used to endorse or promote products derived from this software
53  *    without specific prior written permission.
54  *
55  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
56  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
57  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
58  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
59  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
60  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
61  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
62  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
63  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
64  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
65  * SUCH DAMAGE.
66  *
67  *	@(#)com.c	7.5 (Berkeley) 5/16/91
68  */
69 
70 /*
71  * COM driver, uses National Semiconductor NS16450/NS16550AF UART
72  * Supports automatic hardware flow control on StarTech ST16C650A UART
73  */
74 
75 #include <sys/cdefs.h>
76 __KERNEL_RCSID(0, "$NetBSD: com.c,v 1.238 2005/12/11 12:21:26 christos Exp $");
77 
78 #include "opt_com.h"
79 #include "opt_ddb.h"
80 #include "opt_kgdb.h"
81 #include "opt_lockdebug.h"
82 #include "opt_multiprocessor.h"
83 #include "opt_ntp.h"
84 
85 #include "rnd.h"
86 #if NRND > 0 && defined(RND_COM)
87 #include <sys/rnd.h>
88 #endif
89 
90 /* The COM16650 option was renamed to COM_16650. */
91 #ifdef COM16650
92 #error Obsolete COM16650 option; use COM_16650 instead.
93 #endif
94 
95 /*
96  * Override cnmagic(9) macro before including <sys/systm.h>.
97  * We need to know if cn_check_magic triggered debugger, so set a flag.
98  * Callers of cn_check_magic must declare int cn_trapped = 0;
99  * XXX: this is *ugly*!
100  */
101 #define cn_trap()				\
102 	do {					\
103 		console_debugger();		\
104 		cn_trapped = 1;			\
105 	} while (/* CONSTCOND */ 0)
106 
107 #include <sys/param.h>
108 #include <sys/systm.h>
109 #include <sys/ioctl.h>
110 #include <sys/select.h>
111 #include <sys/poll.h>
112 #include <sys/tty.h>
113 #include <sys/proc.h>
114 #include <sys/user.h>
115 #include <sys/conf.h>
116 #include <sys/file.h>
117 #include <sys/uio.h>
118 #include <sys/kernel.h>
119 #include <sys/syslog.h>
120 #include <sys/device.h>
121 #include <sys/malloc.h>
122 #include <sys/timepps.h>
123 #include <sys/vnode.h>
124 
125 #include <machine/intr.h>
126 #include <machine/bus.h>
127 
128 #include <dev/ic/comreg.h>
129 #include <dev/ic/comvar.h>
130 #include <dev/ic/ns16550reg.h>
131 #include <dev/ic/st16650reg.h>
132 #ifdef COM_HAYESP
133 #include <dev/ic/hayespreg.h>
134 #endif
135 #define	com_lcr	com_cfcr
136 #include <dev/cons.h>
137 
138 #ifdef COM_HAYESP
139 int comprobeHAYESP(bus_space_handle_t hayespioh, struct com_softc *sc);
140 #endif
141 
142 static void com_enable_debugport(struct com_softc *);
143 
144 void	com_config(struct com_softc *);
145 void	com_shutdown(struct com_softc *);
146 int	comspeed(long, long, int);
147 static	u_char	cflag2lcr(tcflag_t);
148 int	comparam(struct tty *, struct termios *);
149 void	comstart(struct tty *);
150 int	comhwiflow(struct tty *, int);
151 
152 void	com_loadchannelregs(struct com_softc *);
153 void	com_hwiflow(struct com_softc *);
154 void	com_break(struct com_softc *, int);
155 void	com_modem(struct com_softc *, int);
156 void	tiocm_to_com(struct com_softc *, u_long, int);
157 int	com_to_tiocm(struct com_softc *);
158 void	com_iflush(struct com_softc *);
159 
160 int	com_common_getc(dev_t, bus_space_tag_t, bus_space_handle_t);
161 void	com_common_putc(dev_t, bus_space_tag_t, bus_space_handle_t, int);
162 
163 int	cominit(bus_space_tag_t, bus_addr_t, int, int, int, tcflag_t,
164 	    bus_space_handle_t *);
165 
166 int	comcngetc(dev_t);
167 void	comcnputc(dev_t, int);
168 void	comcnpollc(dev_t, int);
169 
170 #define	integrate	static inline
171 #ifdef __HAVE_GENERIC_SOFT_INTERRUPTS
172 void 	comsoft(void *);
173 #else
174 #ifndef __NO_SOFT_SERIAL_INTERRUPT
175 void 	comsoft(void);
176 #else
177 void 	comsoft(void *);
178 static struct callout comsoft_callout = CALLOUT_INITIALIZER;
179 #endif
180 #endif
181 integrate void com_rxsoft(struct com_softc *, struct tty *);
182 integrate void com_txsoft(struct com_softc *, struct tty *);
183 integrate void com_stsoft(struct com_softc *, struct tty *);
184 integrate void com_schedrx(struct com_softc *);
185 void	comdiag(void *);
186 
187 extern struct cfdriver com_cd;
188 
189 dev_type_open(comopen);
190 dev_type_close(comclose);
191 dev_type_read(comread);
192 dev_type_write(comwrite);
193 dev_type_ioctl(comioctl);
194 dev_type_stop(comstop);
195 dev_type_tty(comtty);
196 dev_type_poll(compoll);
197 
198 const struct cdevsw com_cdevsw = {
199 	comopen, comclose, comread, comwrite, comioctl,
200 	comstop, comtty, compoll, nommap, ttykqfilter, D_TTY
201 };
202 
203 /*
204  * Make this an option variable one can patch.
205  * But be warned:  this must be a power of 2!
206  */
207 u_int com_rbuf_size = COM_RING_SIZE;
208 
209 /* Stop input when 3/4 of the ring is full; restart when only 1/4 is full. */
210 u_int com_rbuf_hiwat = (COM_RING_SIZE * 1) / 4;
211 u_int com_rbuf_lowat = (COM_RING_SIZE * 3) / 4;
212 
213 static bus_addr_t	comconsaddr;
214 static bus_space_tag_t comconstag;
215 static bus_space_handle_t comconsioh;
216 static int	comconsattached;
217 static int comconsrate;
218 static tcflag_t comconscflag;
219 static struct cnm_state com_cnm_state;
220 
221 static int ppscap =
222 	PPS_TSFMT_TSPEC |
223 	PPS_CAPTUREASSERT |
224 	PPS_CAPTURECLEAR |
225 	PPS_OFFSETASSERT | PPS_OFFSETCLEAR;
226 
227 #ifndef __HAVE_GENERIC_SOFT_INTERRUPTS
228 #ifdef __NO_SOFT_SERIAL_INTERRUPT
229 volatile int	com_softintr_scheduled;
230 #endif
231 #endif
232 
233 #ifdef KGDB
234 #include <sys/kgdb.h>
235 
236 static bus_addr_t com_kgdb_addr;
237 static bus_space_tag_t com_kgdb_iot;
238 static bus_space_handle_t com_kgdb_ioh;
239 static int com_kgdb_attached;
240 
241 int	com_kgdb_getc(void *);
242 void	com_kgdb_putc(void *, int);
243 #endif /* KGDB */
244 
245 #define	COMUNIT_MASK	0x7ffff
246 #define	COMDIALOUT_MASK	0x80000
247 
248 #define	COMUNIT(x)	(minor(x) & COMUNIT_MASK)
249 #define	COMDIALOUT(x)	(minor(x) & COMDIALOUT_MASK)
250 
251 #define	COM_ISALIVE(sc)	((sc)->enabled != 0 && \
252 			 ISSET((sc)->sc_dev.dv_flags, DVF_ACTIVE))
253 
254 #define	BR	BUS_SPACE_BARRIER_READ
255 #define	BW	BUS_SPACE_BARRIER_WRITE
256 #define COM_BARRIER(t, h, f) bus_space_barrier((t), (h), 0, COM_NPORTS, (f))
257 
258 #if (defined(MULTIPROCESSOR) || defined(LOCKDEBUG)) && defined(COM_MPLOCK)
259 
260 #define COM_LOCK(sc) simple_lock(&(sc)->sc_lock)
261 #define COM_UNLOCK(sc) simple_unlock(&(sc)->sc_lock)
262 
263 #else
264 
265 #define COM_LOCK(sc)
266 #define COM_UNLOCK(sc)
267 
268 #endif
269 
270 /*ARGSUSED*/
271 int
272 comspeed(long speed, long frequency, int type)
273 {
274 #define	divrnd(n, q)	(((n)*2/(q)+1)/2)	/* divide and round off */
275 
276 	int x, err;
277 
278 #if 0
279 	if (speed == 0)
280 		return (0);
281 #endif
282 	if (speed <= 0)
283 		return (-1);
284 	x = divrnd(frequency / 16, speed);
285 	if (x <= 0)
286 		return (-1);
287 	err = divrnd(((quad_t)frequency) * 1000 / 16, speed * x) - 1000;
288 	if (err < 0)
289 		err = -err;
290 	if (err > COM_TOLERANCE)
291 		return (-1);
292 	return (x);
293 
294 #undef	divrnd
295 }
296 
297 #ifdef COM_DEBUG
298 int	com_debug = 0;
299 
300 void comstatus(struct com_softc *, const char *);
301 void
302 comstatus(struct com_softc *sc, const char *str)
303 {
304 	struct tty *tp = sc->sc_tty;
305 
306 	printf("%s: %s %cclocal  %cdcd %cts_carr_on %cdtr %ctx_stopped\n",
307 	    sc->sc_dev.dv_xname, str,
308 	    ISSET(tp->t_cflag, CLOCAL) ? '+' : '-',
309 	    ISSET(sc->sc_msr, MSR_DCD) ? '+' : '-',
310 	    ISSET(tp->t_state, TS_CARR_ON) ? '+' : '-',
311 	    ISSET(sc->sc_mcr, MCR_DTR) ? '+' : '-',
312 	    sc->sc_tx_stopped ? '+' : '-');
313 
314 	printf("%s: %s %ccrtscts %ccts %cts_ttstop  %crts rx_flags=0x%x\n",
315 	    sc->sc_dev.dv_xname, str,
316 	    ISSET(tp->t_cflag, CRTSCTS) ? '+' : '-',
317 	    ISSET(sc->sc_msr, MSR_CTS) ? '+' : '-',
318 	    ISSET(tp->t_state, TS_TTSTOP) ? '+' : '-',
319 	    ISSET(sc->sc_mcr, MCR_RTS) ? '+' : '-',
320 	    sc->sc_rx_flags);
321 }
322 #endif
323 
324 int
325 comprobe1(bus_space_tag_t iot, bus_space_handle_t ioh)
326 {
327 
328 	/* force access to id reg */
329 	bus_space_write_1(iot, ioh, com_lcr, LCR_8BITS);
330 	bus_space_write_1(iot, ioh, com_iir, 0);
331 	if ((bus_space_read_1(iot, ioh, com_lcr) != LCR_8BITS) ||
332 	    (bus_space_read_1(iot, ioh, com_iir) & 0x38))
333 		return (0);
334 
335 	return (1);
336 }
337 
338 #ifdef COM_HAYESP
339 int
340 comprobeHAYESP(bus_space_handle_t hayespioh, struct com_softc *sc)
341 {
342 	char	val, dips;
343 	int	combaselist[] = { 0x3f8, 0x2f8, 0x3e8, 0x2e8 };
344 	bus_space_tag_t iot = sc->sc_iot;
345 
346 	/*
347 	 * Hayes ESP cards have two iobases.  One is for compatibility with
348 	 * 16550 serial chips, and at the same ISA PC base addresses.  The
349 	 * other is for ESP-specific enhanced features, and lies at a
350 	 * different addressing range entirely (0x140, 0x180, 0x280, or 0x300).
351 	 */
352 
353 	/* Test for ESP signature */
354 	if ((bus_space_read_1(iot, hayespioh, 0) & 0xf3) == 0)
355 		return (0);
356 
357 	/*
358 	 * ESP is present at ESP enhanced base address; unknown com port
359 	 */
360 
361 	/* Get the dip-switch configurations */
362 	bus_space_write_1(iot, hayespioh, HAYESP_CMD1, HAYESP_GETDIPS);
363 	dips = bus_space_read_1(iot, hayespioh, HAYESP_STATUS1);
364 
365 	/* Determine which com port this ESP card services: bits 0,1 of  */
366 	/*  dips is the port # (0-3); combaselist[val] is the com_iobase */
367 	if (sc->sc_iobase != combaselist[dips & 0x03])
368 		return (0);
369 
370 	printf(": ESP");
371 
372  	/* Check ESP Self Test bits. */
373 	/* Check for ESP version 2.0: bits 4,5,6 == 010 */
374 	bus_space_write_1(iot, hayespioh, HAYESP_CMD1, HAYESP_GETTEST);
375 	val = bus_space_read_1(iot, hayespioh, HAYESP_STATUS1); /* Clear reg1 */
376 	val = bus_space_read_1(iot, hayespioh, HAYESP_STATUS2);
377 	if ((val & 0x70) < 0x20) {
378 		printf("-old (%o)", val & 0x70);
379 		/* we do not support the necessary features */
380 		return (0);
381 	}
382 
383 	/* Check for ability to emulate 16550: bit 8 == 1 */
384 	if ((dips & 0x80) == 0) {
385 		printf(" slave");
386 		/* XXX Does slave really mean no 16550 support?? */
387 		return (0);
388 	}
389 
390 	/*
391 	 * If we made it this far, we are a full-featured ESP v2.0 (or
392 	 * better), at the correct com port address.
393 	 */
394 
395 	sc->sc_type = COM_TYPE_HAYESP;
396 	printf(", 1024 byte fifo\n");
397 	return (1);
398 }
399 #endif
400 
401 static void
402 com_enable_debugport(struct com_softc *sc)
403 {
404 	int s;
405 
406 	/* Turn on line break interrupt, set carrier. */
407 	s = splserial();
408 	COM_LOCK(sc);
409 	sc->sc_ier = IER_ERXRDY;
410 #ifdef COM_PXA2X0
411 	if (sc->sc_type == COM_TYPE_PXA2x0)
412 		sc->sc_ier |= IER_EUART | IER_ERXTOUT;
413 #endif
414 	bus_space_write_1(sc->sc_iot, sc->sc_ioh, com_ier, sc->sc_ier);
415 	SET(sc->sc_mcr, MCR_DTR | MCR_RTS);
416 	bus_space_write_1(sc->sc_iot, sc->sc_ioh, com_mcr, sc->sc_mcr);
417 	COM_UNLOCK(sc);
418 	splx(s);
419 }
420 
421 void
422 com_attach_subr(struct com_softc *sc)
423 {
424 	bus_addr_t iobase = sc->sc_iobase;
425 	bus_space_tag_t iot = sc->sc_iot;
426 	bus_space_handle_t ioh = sc->sc_ioh;
427 	struct tty *tp;
428 #ifdef COM_16650
429 	u_int8_t lcr;
430 #endif
431 #ifdef COM_HAYESP
432 	int	hayesp_ports[] = { 0x140, 0x180, 0x280, 0x300, 0 };
433 	int	*hayespp;
434 #endif
435 	const char *fifo_msg = NULL;
436 
437 	callout_init(&sc->sc_diag_callout);
438 #if (defined(MULTIPROCESSOR) || defined(LOCKDEBUG)) && defined(COM_MPLOCK)
439 	simple_lock_init(&sc->sc_lock);
440 #endif
441 
442 	/* Disable interrupts before configuring the device. */
443 #ifdef COM_PXA2X0
444 	if (sc->sc_type == COM_TYPE_PXA2x0)
445 		sc->sc_ier = IER_EUART;
446 	else
447 #endif
448 		sc->sc_ier = 0;
449 	bus_space_write_1(iot, ioh, com_ier, sc->sc_ier);
450 
451 	if (iot == comconstag && iobase == comconsaddr) {
452 		comconsattached = 1;
453 
454 		/* Make sure the console is always "hardwired". */
455 		delay(10000);			/* wait for output to finish */
456 		SET(sc->sc_hwflags, COM_HW_CONSOLE);
457 		SET(sc->sc_swflags, TIOCFLAG_SOFTCAR);
458 	}
459 
460 #ifdef COM_HAYESP
461 	sc->sc_prescaler = 0;			/* set prescaler to x1. */
462 
463 	/* Look for a Hayes ESP board. */
464 	for (hayespp = hayesp_ports; *hayespp != 0; hayespp++) {
465 		bus_space_handle_t hayespioh;
466 
467 #define	HAYESP_NPORTS	8			/* XXX XXX XXX ??? ??? ??? */
468 		if (bus_space_map(iot, *hayespp, HAYESP_NPORTS, 0, &hayespioh))
469 			continue;
470 		if (comprobeHAYESP(hayespioh, sc)) {
471 			sc->sc_hayespioh = hayespioh;
472 			sc->sc_fifolen = 1024;
473 
474 			break;
475 		}
476 		bus_space_unmap(iot, hayespioh, HAYESP_NPORTS);
477 	}
478 	/* No ESP; look for other things. */
479 	if (sc->sc_type != COM_TYPE_HAYESP) {
480 #endif
481 	sc->sc_fifolen = 1;
482 	/* look for a NS 16550AF UART with FIFOs */
483 	bus_space_write_1(iot, ioh, com_fifo,
484 	    FIFO_ENABLE | FIFO_RCV_RST | FIFO_XMT_RST | FIFO_TRIGGER_14);
485 	delay(100);
486 	if (ISSET(bus_space_read_1(iot, ioh, com_iir), IIR_FIFO_MASK)
487 	    == IIR_FIFO_MASK)
488 		if (ISSET(bus_space_read_1(iot, ioh, com_fifo), FIFO_TRIGGER_14)
489 		    == FIFO_TRIGGER_14) {
490 			SET(sc->sc_hwflags, COM_HW_FIFO);
491 
492 #ifdef COM_16650
493 			/*
494 			 * IIR changes into the EFR if LCR is set to LCR_EERS
495 			 * on 16650s. We also know IIR != 0 at this point.
496 			 * Write 0 into the EFR, and read it. If the result
497 			 * is 0, we have a 16650.
498 			 *
499 			 * Older 16650s were broken; the test to detect them
500 			 * is taken from the Linux driver. Apparently
501 			 * setting DLAB enable gives access to the EFR on
502 			 * these chips.
503 			 */
504 			lcr = bus_space_read_1(iot, ioh, com_lcr);
505 			bus_space_write_1(iot, ioh, com_lcr, LCR_EERS);
506 			bus_space_write_1(iot, ioh, com_efr, 0);
507 			if (bus_space_read_1(iot, ioh, com_efr) == 0) {
508 				bus_space_write_1(iot, ioh, com_lcr,
509 				    lcr | LCR_DLAB);
510 				if (bus_space_read_1(iot, ioh, com_efr) == 0) {
511 					CLR(sc->sc_hwflags, COM_HW_FIFO);
512 					sc->sc_fifolen = 0;
513 				} else {
514 					SET(sc->sc_hwflags, COM_HW_FLOW);
515 					sc->sc_fifolen = 32;
516 				}
517 			} else
518 #endif
519 				sc->sc_fifolen = 16;
520 
521 #ifdef COM_16650
522 			bus_space_write_1(iot, ioh, com_lcr, lcr);
523 			if (sc->sc_fifolen == 0)
524 				fifo_msg = "st16650, broken fifo";
525 			else if (sc->sc_fifolen == 32)
526 				fifo_msg = "st16650a, working fifo";
527 			else
528 #endif
529 				fifo_msg = "ns16550a, working fifo";
530 		} else
531 			fifo_msg = "ns16550, broken fifo";
532 	else
533 		fifo_msg = "ns8250 or ns16450, no fifo";
534 	bus_space_write_1(iot, ioh, com_fifo, 0);
535 	/*
536 	 * Some chips will clear down both Tx and Rx FIFOs when zero is
537 	 * written to com_fifo. If this chip is the console, writing zero
538 	 * results in some of the chip/FIFO description being lost, so delay
539 	 * printing it until now.
540 	 */
541 	delay(10);
542 	aprint_normal(": %s\n", fifo_msg);
543 	if (ISSET(sc->sc_hwflags, COM_HW_TXFIFO_DISABLE)) {
544 		sc->sc_fifolen = 1;
545 		aprint_normal("%s: txfifo disabled\n", sc->sc_dev.dv_xname);
546 	}
547 #ifdef COM_HAYESP
548 	}
549 #endif
550 
551 	tp = ttymalloc();
552 	tp->t_oproc = comstart;
553 	tp->t_param = comparam;
554 	tp->t_hwiflow = comhwiflow;
555 
556 	sc->sc_tty = tp;
557 	sc->sc_rbuf = malloc(com_rbuf_size << 1, M_DEVBUF, M_NOWAIT);
558 	sc->sc_rbput = sc->sc_rbget = sc->sc_rbuf;
559 	sc->sc_rbavail = com_rbuf_size;
560 	if (sc->sc_rbuf == NULL) {
561 		aprint_error("%s: unable to allocate ring buffer\n",
562 		    sc->sc_dev.dv_xname);
563 		return;
564 	}
565 	sc->sc_ebuf = sc->sc_rbuf + (com_rbuf_size << 1);
566 
567 	tty_attach(tp);
568 
569 	if (!ISSET(sc->sc_hwflags, COM_HW_NOIEN))
570 		SET(sc->sc_mcr, MCR_IENABLE);
571 
572 	if (ISSET(sc->sc_hwflags, COM_HW_CONSOLE)) {
573 		int maj;
574 
575 		/* locate the major number */
576 		maj = cdevsw_lookup_major(&com_cdevsw);
577 
578 		tp->t_dev = cn_tab->cn_dev = makedev(maj, sc->sc_dev.dv_unit);
579 
580 		aprint_normal("%s: console\n", sc->sc_dev.dv_xname);
581 	}
582 
583 #ifdef KGDB
584 	/*
585 	 * Allow kgdb to "take over" this port.  If this is
586 	 * not the console and is the kgdb device, it has
587 	 * exclusive use.  If it's the console _and_ the
588 	 * kgdb device, it doesn't.
589 	 */
590 	if (iot == com_kgdb_iot && iobase == com_kgdb_addr) {
591 		if (!ISSET(sc->sc_hwflags, COM_HW_CONSOLE)) {
592 			com_kgdb_attached = 1;
593 
594 			SET(sc->sc_hwflags, COM_HW_KGDB);
595 		}
596 		aprint_normal("%s: kgdb\n", sc->sc_dev.dv_xname);
597 	}
598 #endif
599 
600 #ifdef __HAVE_GENERIC_SOFT_INTERRUPTS
601 	sc->sc_si = softintr_establish(IPL_SOFTSERIAL, comsoft, sc);
602 #endif
603 
604 #if NRND > 0 && defined(RND_COM)
605 	rnd_attach_source(&sc->rnd_source, sc->sc_dev.dv_xname,
606 			  RND_TYPE_TTY, 0);
607 #endif
608 
609 	/* if there are no enable/disable functions, assume the device
610 	   is always enabled */
611 	if (!sc->enable)
612 		sc->enabled = 1;
613 
614 	com_config(sc);
615 
616 	SET(sc->sc_hwflags, COM_HW_DEV_OK);
617 }
618 
619 void
620 com_config(struct com_softc *sc)
621 {
622 	bus_space_tag_t iot = sc->sc_iot;
623 	bus_space_handle_t ioh = sc->sc_ioh;
624 
625 	/* Disable interrupts before configuring the device. */
626 #ifdef COM_PXA2X0
627 	if (sc->sc_type == COM_TYPE_PXA2x0)
628 		sc->sc_ier = IER_EUART;
629 	else
630 #endif
631 		sc->sc_ier = 0;
632 	bus_space_write_1(iot, ioh, com_ier, sc->sc_ier);
633 	(void) bus_space_read_1(iot, ioh, com_iir);
634 
635 #ifdef COM_HAYESP
636 	/* Look for a Hayes ESP board. */
637 	if (sc->sc_type == COM_TYPE_HAYESP) {
638 		sc->sc_fifolen = 1024;
639 
640 		/* Set 16550 compatibility mode */
641 		bus_space_write_1(iot, sc->sc_hayespioh, HAYESP_CMD1,
642 				  HAYESP_SETMODE);
643 		bus_space_write_1(iot, sc->sc_hayespioh, HAYESP_CMD2,
644 				  HAYESP_MODE_FIFO|HAYESP_MODE_RTS|
645 				  HAYESP_MODE_SCALE);
646 
647 		/* Set RTS/CTS flow control */
648 		bus_space_write_1(iot, sc->sc_hayespioh, HAYESP_CMD1,
649 				  HAYESP_SETFLOWTYPE);
650 		bus_space_write_1(iot, sc->sc_hayespioh, HAYESP_CMD2,
651 				  HAYESP_FLOW_RTS);
652 		bus_space_write_1(iot, sc->sc_hayespioh, HAYESP_CMD2,
653 				  HAYESP_FLOW_CTS);
654 
655 		/* Set flow control levels */
656 		bus_space_write_1(iot, sc->sc_hayespioh, HAYESP_CMD1,
657 				  HAYESP_SETRXFLOW);
658 		bus_space_write_1(iot, sc->sc_hayespioh, HAYESP_CMD2,
659 				  HAYESP_HIBYTE(HAYESP_RXHIWMARK));
660 		bus_space_write_1(iot, sc->sc_hayespioh, HAYESP_CMD2,
661 				  HAYESP_LOBYTE(HAYESP_RXHIWMARK));
662 		bus_space_write_1(iot, sc->sc_hayespioh, HAYESP_CMD2,
663 				  HAYESP_HIBYTE(HAYESP_RXLOWMARK));
664 		bus_space_write_1(iot, sc->sc_hayespioh, HAYESP_CMD2,
665 				  HAYESP_LOBYTE(HAYESP_RXLOWMARK));
666 	}
667 #endif
668 
669 	if (ISSET(sc->sc_hwflags, COM_HW_CONSOLE|COM_HW_KGDB))
670 		com_enable_debugport(sc);
671 }
672 
673 int
674 com_detach(struct device *self, int flags)
675 {
676 	struct com_softc *sc = (struct com_softc *)self;
677 	int maj, mn;
678 
679 	/* locate the major number */
680 	maj = cdevsw_lookup_major(&com_cdevsw);
681 
682 	/* Nuke the vnodes for any open instances. */
683 	mn = self->dv_unit;
684 	vdevgone(maj, mn, mn, VCHR);
685 
686 	mn |= COMDIALOUT_MASK;
687 	vdevgone(maj, mn, mn, VCHR);
688 
689 	if (sc->sc_rbuf == NULL) {
690 		/*
691 		 * Ring buffer allocation failed in the com_attach_subr,
692 		 * only the tty is allocated, and nothing else.
693 		 */
694 		ttyfree(sc->sc_tty);
695 		return 0;
696 	}
697 
698 	/* Free the receive buffer. */
699 	free(sc->sc_rbuf, M_DEVBUF);
700 
701 	/* Detach and free the tty. */
702 	tty_detach(sc->sc_tty);
703 	ttyfree(sc->sc_tty);
704 
705 #ifdef __HAVE_GENERIC_SOFT_INTERRUPTS
706 	/* Unhook the soft interrupt handler. */
707 	softintr_disestablish(sc->sc_si);
708 #endif
709 
710 #if NRND > 0 && defined(RND_COM)
711 	/* Unhook the entropy source. */
712 	rnd_detach_source(&sc->rnd_source);
713 #endif
714 
715 	return (0);
716 }
717 
718 int
719 com_activate(struct device *self, enum devact act)
720 {
721 	struct com_softc *sc = (struct com_softc *)self;
722 	int s, rv = 0;
723 
724 	s = splserial();
725 	COM_LOCK(sc);
726 	switch (act) {
727 	case DVACT_ACTIVATE:
728 		rv = EOPNOTSUPP;
729 		break;
730 
731 	case DVACT_DEACTIVATE:
732 		if (sc->sc_hwflags & (COM_HW_CONSOLE|COM_HW_KGDB)) {
733 			rv = EBUSY;
734 			break;
735 		}
736 
737 		if (sc->disable != NULL && sc->enabled != 0) {
738 			(*sc->disable)(sc);
739 			sc->enabled = 0;
740 		}
741 		break;
742 	}
743 
744 	COM_UNLOCK(sc);
745 	splx(s);
746 	return (rv);
747 }
748 
749 void
750 com_shutdown(struct com_softc *sc)
751 {
752 	struct tty *tp = sc->sc_tty;
753 	int s;
754 
755 	s = splserial();
756 	COM_LOCK(sc);
757 
758 	/* If we were asserting flow control, then deassert it. */
759 	SET(sc->sc_rx_flags, RX_IBUF_BLOCKED);
760 	com_hwiflow(sc);
761 
762 	/* Clear any break condition set with TIOCSBRK. */
763 	com_break(sc, 0);
764 
765 	/* Turn off PPS capture on last close. */
766 	sc->sc_ppsmask = 0;
767 	sc->ppsparam.mode = 0;
768 
769 	/*
770 	 * Hang up if necessary.  Wait a bit, so the other side has time to
771 	 * notice even if we immediately open the port again.
772 	 * Avoid tsleeping above splhigh().
773 	 */
774 	if (ISSET(tp->t_cflag, HUPCL)) {
775 		com_modem(sc, 0);
776 		COM_UNLOCK(sc);
777 		splx(s);
778 		/* XXX tsleep will only timeout */
779 		(void) tsleep(sc, TTIPRI, ttclos, hz);
780 		s = splserial();
781 		COM_LOCK(sc);
782 	}
783 
784 	/* Turn off interrupts. */
785 	if (ISSET(sc->sc_hwflags, COM_HW_CONSOLE)) {
786 		sc->sc_ier = IER_ERXRDY; /* interrupt on break */
787 #ifdef COM_PXA2X0
788 		if (sc->sc_type == COM_TYPE_PXA2x0)
789 			sc->sc_ier |= IER_ERXTOUT;
790 #endif
791 	} else
792 		sc->sc_ier = 0;
793 
794 #ifdef COM_PXA2X0
795 	if (sc->sc_type == COM_TYPE_PXA2x0)
796 		sc->sc_ier |= IER_EUART;
797 #endif
798 
799 	bus_space_write_1(sc->sc_iot, sc->sc_ioh, com_ier, sc->sc_ier);
800 
801 	if (sc->disable) {
802 #ifdef DIAGNOSTIC
803 		if (!sc->enabled)
804 			panic("com_shutdown: not enabled?");
805 #endif
806 		(*sc->disable)(sc);
807 		sc->enabled = 0;
808 	}
809 	COM_UNLOCK(sc);
810 	splx(s);
811 }
812 
813 int
814 comopen(dev_t dev, int flag, int mode, struct lwp *l)
815 {
816 	struct com_softc *sc;
817 	struct tty *tp;
818 	int s, s2;
819 	int error;
820 
821 	sc = device_lookup(&com_cd, COMUNIT(dev));
822 	if (sc == NULL || !ISSET(sc->sc_hwflags, COM_HW_DEV_OK) ||
823 		sc->sc_rbuf == NULL)
824 		return (ENXIO);
825 
826 	if (ISSET(sc->sc_dev.dv_flags, DVF_ACTIVE) == 0)
827 		return (ENXIO);
828 
829 #ifdef KGDB
830 	/*
831 	 * If this is the kgdb port, no other use is permitted.
832 	 */
833 	if (ISSET(sc->sc_hwflags, COM_HW_KGDB))
834 		return (EBUSY);
835 #endif
836 
837 	tp = sc->sc_tty;
838 
839 	if (ISSET(tp->t_state, TS_ISOPEN) &&
840 	    ISSET(tp->t_state, TS_XCLUDE) &&
841 		suser(l->l_proc->p_ucred, &l->l_proc->p_acflag) != 0)
842 		return (EBUSY);
843 
844 	s = spltty();
845 
846 	/*
847 	 * Do the following iff this is a first open.
848 	 */
849 	if (!ISSET(tp->t_state, TS_ISOPEN) && tp->t_wopen == 0) {
850 		struct termios t;
851 
852 		tp->t_dev = dev;
853 
854 		s2 = splserial();
855 		COM_LOCK(sc);
856 
857 		if (sc->enable) {
858 			if ((*sc->enable)(sc)) {
859 				COM_UNLOCK(sc);
860 				splx(s2);
861 				splx(s);
862 				printf("%s: device enable failed\n",
863 				       sc->sc_dev.dv_xname);
864 				return (EIO);
865 			}
866 			sc->enabled = 1;
867 			com_config(sc);
868 		}
869 
870 		/* Turn on interrupts. */
871 		sc->sc_ier = IER_ERXRDY | IER_ERLS | IER_EMSC;
872 #ifdef COM_PXA2X0
873 		if (sc->sc_type == COM_TYPE_PXA2x0)
874 			sc->sc_ier |= IER_EUART | IER_ERXTOUT;
875 #endif
876 		bus_space_write_1(sc->sc_iot, sc->sc_ioh, com_ier, sc->sc_ier);
877 
878 		/* Fetch the current modem control status, needed later. */
879 		sc->sc_msr = bus_space_read_1(sc->sc_iot, sc->sc_ioh, com_msr);
880 
881 		/* Clear PPS capture state on first open. */
882 		sc->sc_ppsmask = 0;
883 		sc->ppsparam.mode = 0;
884 
885 		COM_UNLOCK(sc);
886 		splx(s2);
887 
888 		/*
889 		 * Initialize the termios status to the defaults.  Add in the
890 		 * sticky bits from TIOCSFLAGS.
891 		 */
892 		if (ISSET(sc->sc_hwflags, COM_HW_CONSOLE)) {
893 			t.c_ospeed = comconsrate;
894 			t.c_cflag = comconscflag;
895 		} else {
896 			t.c_ospeed = TTYDEF_SPEED;
897 			t.c_cflag = TTYDEF_CFLAG;
898 		}
899 		t.c_ispeed = t.c_ospeed;
900 		if (ISSET(sc->sc_swflags, TIOCFLAG_CLOCAL))
901 			SET(t.c_cflag, CLOCAL);
902 		if (ISSET(sc->sc_swflags, TIOCFLAG_CRTSCTS))
903 			SET(t.c_cflag, CRTSCTS);
904 		if (ISSET(sc->sc_swflags, TIOCFLAG_MDMBUF))
905 			SET(t.c_cflag, MDMBUF);
906 		/* Make sure comparam() will do something. */
907 		tp->t_ospeed = 0;
908 		(void) comparam(tp, &t);
909 		tp->t_iflag = TTYDEF_IFLAG;
910 		tp->t_oflag = TTYDEF_OFLAG;
911 		tp->t_lflag = TTYDEF_LFLAG;
912 		ttychars(tp);
913 		ttsetwater(tp);
914 
915 		s2 = splserial();
916 		COM_LOCK(sc);
917 
918 		/*
919 		 * Turn on DTR.  We must always do this, even if carrier is not
920 		 * present, because otherwise we'd have to use TIOCSDTR
921 		 * immediately after setting CLOCAL, which applications do not
922 		 * expect.  We always assert DTR while the device is open
923 		 * unless explicitly requested to deassert it.
924 		 */
925 		com_modem(sc, 1);
926 
927 		/* Clear the input ring, and unblock. */
928 		sc->sc_rbput = sc->sc_rbget = sc->sc_rbuf;
929 		sc->sc_rbavail = com_rbuf_size;
930 		com_iflush(sc);
931 		CLR(sc->sc_rx_flags, RX_ANY_BLOCK);
932 		com_hwiflow(sc);
933 
934 #ifdef COM_DEBUG
935 		if (com_debug)
936 			comstatus(sc, "comopen  ");
937 #endif
938 
939 		COM_UNLOCK(sc);
940 		splx(s2);
941 	}
942 
943 	splx(s);
944 
945 	error = ttyopen(tp, COMDIALOUT(dev), ISSET(flag, O_NONBLOCK));
946 	if (error)
947 		goto bad;
948 
949 	error = (*tp->t_linesw->l_open)(dev, tp);
950 	if (error)
951 		goto bad;
952 
953 	return (0);
954 
955 bad:
956 	if (!ISSET(tp->t_state, TS_ISOPEN) && tp->t_wopen == 0) {
957 		/*
958 		 * We failed to open the device, and nobody else had it opened.
959 		 * Clean up the state as appropriate.
960 		 */
961 		com_shutdown(sc);
962 	}
963 
964 	return (error);
965 }
966 
967 int
968 comclose(dev_t dev, int flag, int mode, struct lwp *l)
969 {
970 	struct com_softc *sc = device_lookup(&com_cd, COMUNIT(dev));
971 	struct tty *tp = sc->sc_tty;
972 
973 	/* XXX This is for cons.c. */
974 	if (!ISSET(tp->t_state, TS_ISOPEN))
975 		return (0);
976 
977 	(*tp->t_linesw->l_close)(tp, flag);
978 	ttyclose(tp);
979 
980 	if (COM_ISALIVE(sc) == 0)
981 		return (0);
982 
983 	if (!ISSET(tp->t_state, TS_ISOPEN) && tp->t_wopen == 0) {
984 		/*
985 		 * Although we got a last close, the device may still be in
986 		 * use; e.g. if this was the dialout node, and there are still
987 		 * processes waiting for carrier on the non-dialout node.
988 		 */
989 		com_shutdown(sc);
990 	}
991 
992 	return (0);
993 }
994 
995 int
996 comread(dev_t dev, struct uio *uio, int flag)
997 {
998 	struct com_softc *sc = device_lookup(&com_cd, COMUNIT(dev));
999 	struct tty *tp = sc->sc_tty;
1000 
1001 	if (COM_ISALIVE(sc) == 0)
1002 		return (EIO);
1003 
1004 	return ((*tp->t_linesw->l_read)(tp, uio, flag));
1005 }
1006 
1007 int
1008 comwrite(dev_t dev, struct uio *uio, int flag)
1009 {
1010 	struct com_softc *sc = device_lookup(&com_cd, COMUNIT(dev));
1011 	struct tty *tp = sc->sc_tty;
1012 
1013 	if (COM_ISALIVE(sc) == 0)
1014 		return (EIO);
1015 
1016 	return ((*tp->t_linesw->l_write)(tp, uio, flag));
1017 }
1018 
1019 int
1020 compoll(dev_t dev, int events, struct lwp *l)
1021 {
1022 	struct com_softc *sc = device_lookup(&com_cd, COMUNIT(dev));
1023 	struct tty *tp = sc->sc_tty;
1024 
1025 	if (COM_ISALIVE(sc) == 0)
1026 		return (POLLHUP);
1027 
1028 	return ((*tp->t_linesw->l_poll)(tp, events, l));
1029 }
1030 
1031 struct tty *
1032 comtty(dev_t dev)
1033 {
1034 	struct com_softc *sc = device_lookup(&com_cd, COMUNIT(dev));
1035 	struct tty *tp = sc->sc_tty;
1036 
1037 	return (tp);
1038 }
1039 
1040 int
1041 comioctl(dev_t dev, u_long cmd, caddr_t data, int flag, struct lwp *l)
1042 {
1043 	struct com_softc *sc = device_lookup(&com_cd, COMUNIT(dev));
1044 	struct tty *tp = sc->sc_tty;
1045 	struct proc *p = l->l_proc;
1046 	int error;
1047 	int s;
1048 
1049 	if (COM_ISALIVE(sc) == 0)
1050 		return (EIO);
1051 
1052 	error = (*tp->t_linesw->l_ioctl)(tp, cmd, data, flag, l);
1053 	if (error != EPASSTHROUGH)
1054 		return (error);
1055 
1056 	error = ttioctl(tp, cmd, data, flag, l);
1057 	if (error != EPASSTHROUGH)
1058 		return (error);
1059 
1060 	error = 0;
1061 
1062 	s = splserial();
1063 	COM_LOCK(sc);
1064 
1065 	switch (cmd) {
1066 	case TIOCSBRK:
1067 		com_break(sc, 1);
1068 		break;
1069 
1070 	case TIOCCBRK:
1071 		com_break(sc, 0);
1072 		break;
1073 
1074 	case TIOCSDTR:
1075 		com_modem(sc, 1);
1076 		break;
1077 
1078 	case TIOCCDTR:
1079 		com_modem(sc, 0);
1080 		break;
1081 
1082 	case TIOCGFLAGS:
1083 		*(int *)data = sc->sc_swflags;
1084 		break;
1085 
1086 	case TIOCSFLAGS:
1087 		error = suser(p->p_ucred, &p->p_acflag);
1088 		if (error)
1089 			break;
1090 		sc->sc_swflags = *(int *)data;
1091 		break;
1092 
1093 	case TIOCMSET:
1094 	case TIOCMBIS:
1095 	case TIOCMBIC:
1096 		tiocm_to_com(sc, cmd, *(int *)data);
1097 		break;
1098 
1099 	case TIOCMGET:
1100 		*(int *)data = com_to_tiocm(sc);
1101 		break;
1102 
1103 	case PPS_IOC_CREATE:
1104 		break;
1105 
1106 	case PPS_IOC_DESTROY:
1107 		break;
1108 
1109 	case PPS_IOC_GETPARAMS: {
1110 		pps_params_t *pp;
1111 		pp = (pps_params_t *)data;
1112 		*pp = sc->ppsparam;
1113 		break;
1114 	}
1115 
1116 	case PPS_IOC_SETPARAMS: {
1117 	  	pps_params_t *pp;
1118 		int mode;
1119 		pp = (pps_params_t *)data;
1120 		if (pp->mode & ~ppscap) {
1121 			error = EINVAL;
1122 			break;
1123 		}
1124 		sc->ppsparam = *pp;
1125 	 	/*
1126 		 * Compute msr masks from user-specified timestamp state.
1127 		 */
1128 		mode = sc->ppsparam.mode;
1129 		switch (mode & PPS_CAPTUREBOTH) {
1130 		case 0:
1131 			sc->sc_ppsmask = 0;
1132 			break;
1133 
1134 		case PPS_CAPTUREASSERT:
1135 			sc->sc_ppsmask = MSR_DCD;
1136 			sc->sc_ppsassert = MSR_DCD;
1137 			sc->sc_ppsclear = -1;
1138 			break;
1139 
1140 		case PPS_CAPTURECLEAR:
1141 			sc->sc_ppsmask = MSR_DCD;
1142 			sc->sc_ppsassert = -1;
1143 			sc->sc_ppsclear = 0;
1144 			break;
1145 
1146 		case PPS_CAPTUREBOTH:
1147 			sc->sc_ppsmask = MSR_DCD;
1148 			sc->sc_ppsassert = MSR_DCD;
1149 			sc->sc_ppsclear = 0;
1150 			break;
1151 
1152 		default:
1153 			error = EINVAL;
1154 			break;
1155 		}
1156 		break;
1157 	}
1158 
1159 	case PPS_IOC_GETCAP:
1160 		*(int*)data = ppscap;
1161 		break;
1162 
1163 	case PPS_IOC_FETCH: {
1164 		pps_info_t *pi;
1165 		pi = (pps_info_t *)data;
1166 		*pi = sc->ppsinfo;
1167 		break;
1168 	}
1169 
1170 #ifdef PPS_SYNC
1171 	case PPS_IOC_KCBIND: {
1172 		int edge = (*(int *)data) & PPS_CAPTUREBOTH;
1173 
1174 		if (edge == 0) {
1175 			/*
1176 			 * remove binding for this source; ignore
1177 			 * the request if this is not the current
1178 			 * hardpps source
1179 			 */
1180 			if (pps_kc_hardpps_source == sc) {
1181 				pps_kc_hardpps_source = NULL;
1182 				pps_kc_hardpps_mode = 0;
1183 			}
1184 		} else {
1185 			/*
1186 			 * bind hardpps to this source, replacing any
1187 			 * previously specified source or edges
1188 			 */
1189 			pps_kc_hardpps_source = sc;
1190 			pps_kc_hardpps_mode = edge;
1191 		}
1192 		break;
1193 	}
1194 #endif /* PPS_SYNC */
1195 
1196 	case TIOCDCDTIMESTAMP:	/* XXX old, overloaded  API used by xntpd v3 */
1197 		/*
1198 		 * Some GPS clocks models use the falling rather than
1199 		 * rising edge as the on-the-second signal.
1200 		 * The old API has no way to specify PPS polarity.
1201 		 */
1202 		sc->sc_ppsmask = MSR_DCD;
1203 #ifndef PPS_TRAILING_EDGE
1204 		sc->sc_ppsassert = MSR_DCD;
1205 		sc->sc_ppsclear = -1;
1206 		TIMESPEC_TO_TIMEVAL((struct timeval *)data,
1207 		    &sc->ppsinfo.assert_timestamp);
1208 #else
1209 		sc->sc_ppsassert = -1;
1210 		sc->sc_ppsclear = 0;
1211 		TIMESPEC_TO_TIMEVAL((struct timeval *)data,
1212 		    &sc->ppsinfo.clear_timestamp);
1213 #endif
1214 		break;
1215 
1216 	default:
1217 		error = EPASSTHROUGH;
1218 		break;
1219 	}
1220 
1221 	COM_UNLOCK(sc);
1222 	splx(s);
1223 
1224 #ifdef COM_DEBUG
1225 	if (com_debug)
1226 		comstatus(sc, "comioctl ");
1227 #endif
1228 
1229 	return (error);
1230 }
1231 
1232 integrate void
1233 com_schedrx(struct com_softc *sc)
1234 {
1235 
1236 	sc->sc_rx_ready = 1;
1237 
1238 	/* Wake up the poller. */
1239 #ifdef __HAVE_GENERIC_SOFT_INTERRUPTS
1240 	softintr_schedule(sc->sc_si);
1241 #else
1242 #ifndef __NO_SOFT_SERIAL_INTERRUPT
1243 	setsoftserial();
1244 #else
1245 	if (!com_softintr_scheduled) {
1246 		com_softintr_scheduled = 1;
1247 		callout_reset(&comsoft_callout, 1, comsoft, NULL);
1248 	}
1249 #endif
1250 #endif
1251 }
1252 
1253 void
1254 com_break(struct com_softc *sc, int onoff)
1255 {
1256 
1257 	if (onoff)
1258 		SET(sc->sc_lcr, LCR_SBREAK);
1259 	else
1260 		CLR(sc->sc_lcr, LCR_SBREAK);
1261 
1262 	if (!sc->sc_heldchange) {
1263 		if (sc->sc_tx_busy) {
1264 			sc->sc_heldtbc = sc->sc_tbc;
1265 			sc->sc_tbc = 0;
1266 			sc->sc_heldchange = 1;
1267 		} else
1268 			com_loadchannelregs(sc);
1269 	}
1270 }
1271 
1272 void
1273 com_modem(struct com_softc *sc, int onoff)
1274 {
1275 
1276 	if (sc->sc_mcr_dtr == 0)
1277 		return;
1278 
1279 	if (onoff)
1280 		SET(sc->sc_mcr, sc->sc_mcr_dtr);
1281 	else
1282 		CLR(sc->sc_mcr, sc->sc_mcr_dtr);
1283 
1284 	if (!sc->sc_heldchange) {
1285 		if (sc->sc_tx_busy) {
1286 			sc->sc_heldtbc = sc->sc_tbc;
1287 			sc->sc_tbc = 0;
1288 			sc->sc_heldchange = 1;
1289 		} else
1290 			com_loadchannelregs(sc);
1291 	}
1292 }
1293 
1294 void
1295 tiocm_to_com(struct com_softc *sc, u_long how, int ttybits)
1296 {
1297 	u_char combits;
1298 
1299 	combits = 0;
1300 	if (ISSET(ttybits, TIOCM_DTR))
1301 		SET(combits, MCR_DTR);
1302 	if (ISSET(ttybits, TIOCM_RTS))
1303 		SET(combits, MCR_RTS);
1304 
1305 	switch (how) {
1306 	case TIOCMBIC:
1307 		CLR(sc->sc_mcr, combits);
1308 		break;
1309 
1310 	case TIOCMBIS:
1311 		SET(sc->sc_mcr, combits);
1312 		break;
1313 
1314 	case TIOCMSET:
1315 		CLR(sc->sc_mcr, MCR_DTR | MCR_RTS);
1316 		SET(sc->sc_mcr, combits);
1317 		break;
1318 	}
1319 
1320 	if (!sc->sc_heldchange) {
1321 		if (sc->sc_tx_busy) {
1322 			sc->sc_heldtbc = sc->sc_tbc;
1323 			sc->sc_tbc = 0;
1324 			sc->sc_heldchange = 1;
1325 		} else
1326 			com_loadchannelregs(sc);
1327 	}
1328 }
1329 
1330 int
1331 com_to_tiocm(struct com_softc *sc)
1332 {
1333 	u_char combits;
1334 	int ttybits = 0;
1335 
1336 	combits = sc->sc_mcr;
1337 	if (ISSET(combits, MCR_DTR))
1338 		SET(ttybits, TIOCM_DTR);
1339 	if (ISSET(combits, MCR_RTS))
1340 		SET(ttybits, TIOCM_RTS);
1341 
1342 	combits = sc->sc_msr;
1343 	if (ISSET(combits, MSR_DCD))
1344 		SET(ttybits, TIOCM_CD);
1345 	if (ISSET(combits, MSR_CTS))
1346 		SET(ttybits, TIOCM_CTS);
1347 	if (ISSET(combits, MSR_DSR))
1348 		SET(ttybits, TIOCM_DSR);
1349 	if (ISSET(combits, MSR_RI | MSR_TERI))
1350 		SET(ttybits, TIOCM_RI);
1351 
1352 	if (ISSET(sc->sc_ier, IER_ERXRDY | IER_ETXRDY | IER_ERLS | IER_EMSC))
1353 		SET(ttybits, TIOCM_LE);
1354 
1355 	return (ttybits);
1356 }
1357 
1358 static u_char
1359 cflag2lcr(tcflag_t cflag)
1360 {
1361 	u_char lcr = 0;
1362 
1363 	switch (ISSET(cflag, CSIZE)) {
1364 	case CS5:
1365 		SET(lcr, LCR_5BITS);
1366 		break;
1367 	case CS6:
1368 		SET(lcr, LCR_6BITS);
1369 		break;
1370 	case CS7:
1371 		SET(lcr, LCR_7BITS);
1372 		break;
1373 	case CS8:
1374 		SET(lcr, LCR_8BITS);
1375 		break;
1376 	}
1377 	if (ISSET(cflag, PARENB)) {
1378 		SET(lcr, LCR_PENAB);
1379 		if (!ISSET(cflag, PARODD))
1380 			SET(lcr, LCR_PEVEN);
1381 	}
1382 	if (ISSET(cflag, CSTOPB))
1383 		SET(lcr, LCR_STOPB);
1384 
1385 	return (lcr);
1386 }
1387 
1388 int
1389 comparam(struct tty *tp, struct termios *t)
1390 {
1391 	struct com_softc *sc = device_lookup(&com_cd, COMUNIT(tp->t_dev));
1392 	int ospeed;
1393 	u_char lcr;
1394 	int s;
1395 
1396 	if (COM_ISALIVE(sc) == 0)
1397 		return (EIO);
1398 
1399 #ifdef COM_HAYESP
1400 	if (sc->sc_type == COM_TYPE_HAYESP) {
1401 		int prescaler, speed;
1402 
1403 		/*
1404 		 * Calculate UART clock prescaler.  It should be in
1405 		 * range of 0 .. 3.
1406 		 */
1407 		for (prescaler = 0, speed = t->c_ospeed; prescaler < 4;
1408 		    prescaler++, speed /= 2)
1409 			if ((ospeed = comspeed(speed, sc->sc_frequency,
1410 					       sc->sc_type)) > 0)
1411 				break;
1412 
1413 		if (prescaler == 4)
1414 			return (EINVAL);
1415 		sc->sc_prescaler = prescaler;
1416 	} else
1417 #endif
1418 	ospeed = comspeed(t->c_ospeed, sc->sc_frequency, sc->sc_type);
1419 
1420 	/* Check requested parameters. */
1421 	if (ospeed < 0)
1422 		return (EINVAL);
1423 	if (t->c_ispeed && t->c_ispeed != t->c_ospeed)
1424 		return (EINVAL);
1425 
1426 	/*
1427 	 * For the console, always force CLOCAL and !HUPCL, so that the port
1428 	 * is always active.
1429 	 */
1430 	if (ISSET(sc->sc_swflags, TIOCFLAG_SOFTCAR) ||
1431 	    ISSET(sc->sc_hwflags, COM_HW_CONSOLE)) {
1432 		SET(t->c_cflag, CLOCAL);
1433 		CLR(t->c_cflag, HUPCL);
1434 	}
1435 
1436 	/*
1437 	 * If there were no changes, don't do anything.  This avoids dropping
1438 	 * input and improves performance when all we did was frob things like
1439 	 * VMIN and VTIME.
1440 	 */
1441 	if (tp->t_ospeed == t->c_ospeed &&
1442 	    tp->t_cflag == t->c_cflag)
1443 		return (0);
1444 
1445 	lcr = ISSET(sc->sc_lcr, LCR_SBREAK) | cflag2lcr(t->c_cflag);
1446 
1447 	s = splserial();
1448 	COM_LOCK(sc);
1449 
1450 	sc->sc_lcr = lcr;
1451 
1452 	/*
1453 	 * If we're not in a mode that assumes a connection is present, then
1454 	 * ignore carrier changes.
1455 	 */
1456 	if (ISSET(t->c_cflag, CLOCAL | MDMBUF))
1457 		sc->sc_msr_dcd = 0;
1458 	else
1459 		sc->sc_msr_dcd = MSR_DCD;
1460 	/*
1461 	 * Set the flow control pins depending on the current flow control
1462 	 * mode.
1463 	 */
1464 	if (ISSET(t->c_cflag, CRTSCTS)) {
1465 		sc->sc_mcr_dtr = MCR_DTR;
1466 		sc->sc_mcr_rts = MCR_RTS;
1467 		sc->sc_msr_cts = MSR_CTS;
1468 		sc->sc_efr = EFR_AUTORTS | EFR_AUTOCTS;
1469 	} else if (ISSET(t->c_cflag, MDMBUF)) {
1470 		/*
1471 		 * For DTR/DCD flow control, make sure we don't toggle DTR for
1472 		 * carrier detection.
1473 		 */
1474 		sc->sc_mcr_dtr = 0;
1475 		sc->sc_mcr_rts = MCR_DTR;
1476 		sc->sc_msr_cts = MSR_DCD;
1477 		sc->sc_efr = 0;
1478 	} else {
1479 		/*
1480 		 * If no flow control, then always set RTS.  This will make
1481 		 * the other side happy if it mistakenly thinks we're doing
1482 		 * RTS/CTS flow control.
1483 		 */
1484 		sc->sc_mcr_dtr = MCR_DTR | MCR_RTS;
1485 		sc->sc_mcr_rts = 0;
1486 		sc->sc_msr_cts = 0;
1487 		sc->sc_efr = 0;
1488 		if (ISSET(sc->sc_mcr, MCR_DTR))
1489 			SET(sc->sc_mcr, MCR_RTS);
1490 		else
1491 			CLR(sc->sc_mcr, MCR_RTS);
1492 	}
1493 	sc->sc_msr_mask = sc->sc_msr_cts | sc->sc_msr_dcd;
1494 
1495 #if 0
1496 	if (ospeed == 0)
1497 		CLR(sc->sc_mcr, sc->sc_mcr_dtr);
1498 	else
1499 		SET(sc->sc_mcr, sc->sc_mcr_dtr);
1500 #endif
1501 
1502 	sc->sc_dlbl = ospeed;
1503 	sc->sc_dlbh = ospeed >> 8;
1504 
1505 	/*
1506 	 * Set the FIFO threshold based on the receive speed.
1507 	 *
1508 	 *  * If it's a low speed, it's probably a mouse or some other
1509 	 *    interactive device, so set the threshold low.
1510 	 *  * If it's a high speed, trim the trigger level down to prevent
1511 	 *    overflows.
1512 	 *  * Otherwise set it a bit higher.
1513 	 */
1514 	if (sc->sc_type == COM_TYPE_HAYESP)
1515 		sc->sc_fifo = FIFO_DMA_MODE | FIFO_ENABLE | FIFO_TRIGGER_8;
1516 	else if (ISSET(sc->sc_hwflags, COM_HW_FIFO))
1517 		sc->sc_fifo = FIFO_ENABLE |
1518 		    (t->c_ospeed <= 1200 ? FIFO_TRIGGER_1 : FIFO_TRIGGER_8);
1519 	else
1520 		sc->sc_fifo = 0;
1521 
1522 	/* And copy to tty. */
1523 	tp->t_ispeed = 0;
1524 	tp->t_ospeed = t->c_ospeed;
1525 	tp->t_cflag = t->c_cflag;
1526 
1527 	if (!sc->sc_heldchange) {
1528 		if (sc->sc_tx_busy) {
1529 			sc->sc_heldtbc = sc->sc_tbc;
1530 			sc->sc_tbc = 0;
1531 			sc->sc_heldchange = 1;
1532 		} else
1533 			com_loadchannelregs(sc);
1534 	}
1535 
1536 	if (!ISSET(t->c_cflag, CHWFLOW)) {
1537 		/* Disable the high water mark. */
1538 		sc->sc_r_hiwat = 0;
1539 		sc->sc_r_lowat = 0;
1540 		if (ISSET(sc->sc_rx_flags, RX_TTY_OVERFLOWED)) {
1541 			CLR(sc->sc_rx_flags, RX_TTY_OVERFLOWED);
1542 			com_schedrx(sc);
1543 		}
1544 		if (ISSET(sc->sc_rx_flags, RX_TTY_BLOCKED|RX_IBUF_BLOCKED)) {
1545 			CLR(sc->sc_rx_flags, RX_TTY_BLOCKED|RX_IBUF_BLOCKED);
1546 			com_hwiflow(sc);
1547 		}
1548 	} else {
1549 		sc->sc_r_hiwat = com_rbuf_hiwat;
1550 		sc->sc_r_lowat = com_rbuf_lowat;
1551 	}
1552 
1553 	COM_UNLOCK(sc);
1554 	splx(s);
1555 
1556 	/*
1557 	 * Update the tty layer's idea of the carrier bit, in case we changed
1558 	 * CLOCAL or MDMBUF.  We don't hang up here; we only do that by
1559 	 * explicit request.
1560 	 */
1561 	(void) (*tp->t_linesw->l_modem)(tp, ISSET(sc->sc_msr, MSR_DCD));
1562 
1563 #ifdef COM_DEBUG
1564 	if (com_debug)
1565 		comstatus(sc, "comparam ");
1566 #endif
1567 
1568 	if (!ISSET(t->c_cflag, CHWFLOW)) {
1569 		if (sc->sc_tx_stopped) {
1570 			sc->sc_tx_stopped = 0;
1571 			comstart(tp);
1572 		}
1573 	}
1574 
1575 	return (0);
1576 }
1577 
1578 void
1579 com_iflush(struct com_softc *sc)
1580 {
1581 	bus_space_tag_t iot = sc->sc_iot;
1582 	bus_space_handle_t ioh = sc->sc_ioh;
1583 #ifdef DIAGNOSTIC
1584 	int reg;
1585 #endif
1586 	int timo;
1587 
1588 #ifdef DIAGNOSTIC
1589 	reg = 0xffff;
1590 #endif
1591 	timo = 50000;
1592 	/* flush any pending I/O */
1593 	while (ISSET(bus_space_read_1(iot, ioh, com_lsr), LSR_RXRDY)
1594 	    && --timo)
1595 #ifdef DIAGNOSTIC
1596 		reg =
1597 #else
1598 		    (void)
1599 #endif
1600 		    bus_space_read_1(iot, ioh, com_data);
1601 #ifdef DIAGNOSTIC
1602 	if (!timo)
1603 		printf("%s: com_iflush timeout %02x\n", sc->sc_dev.dv_xname,
1604 		       reg);
1605 #endif
1606 }
1607 
1608 void
1609 com_loadchannelregs(struct com_softc *sc)
1610 {
1611 	bus_space_tag_t iot = sc->sc_iot;
1612 	bus_space_handle_t ioh = sc->sc_ioh;
1613 
1614 	/* XXXXX necessary? */
1615 	com_iflush(sc);
1616 
1617 #ifdef COM_PXA2X0
1618 	if (sc->sc_type == COM_TYPE_PXA2x0)
1619 		bus_space_write_1(iot, ioh, com_ier, IER_EUART);
1620 	else
1621 #endif
1622 		bus_space_write_1(iot, ioh, com_ier, 0);
1623 
1624 	if (ISSET(sc->sc_hwflags, COM_HW_FLOW)) {
1625 		bus_space_write_1(iot, ioh, com_lcr, LCR_EERS);
1626 		bus_space_write_1(iot, ioh, com_efr, sc->sc_efr);
1627 	}
1628 	bus_space_write_1(iot, ioh, com_lcr, sc->sc_lcr | LCR_DLAB);
1629 	bus_space_write_1(iot, ioh, com_dlbl, sc->sc_dlbl);
1630 	bus_space_write_1(iot, ioh, com_dlbh, sc->sc_dlbh);
1631 	bus_space_write_1(iot, ioh, com_lcr, sc->sc_lcr);
1632 	bus_space_write_1(iot, ioh, com_mcr, sc->sc_mcr_active = sc->sc_mcr);
1633 	bus_space_write_1(iot, ioh, com_fifo, sc->sc_fifo);
1634 #ifdef COM_HAYESP
1635 	if (sc->sc_type == COM_TYPE_HAYESP) {
1636 		bus_space_write_1(iot, sc->sc_hayespioh, HAYESP_CMD1,
1637 		    HAYESP_SETPRESCALER);
1638 		bus_space_write_1(iot, sc->sc_hayespioh, HAYESP_CMD2,
1639 		    sc->sc_prescaler);
1640 	}
1641 #endif
1642 
1643 	bus_space_write_1(iot, ioh, com_ier, sc->sc_ier);
1644 }
1645 
1646 int
1647 comhwiflow(struct tty *tp, int block)
1648 {
1649 	struct com_softc *sc = device_lookup(&com_cd, COMUNIT(tp->t_dev));
1650 	int s;
1651 
1652 	if (COM_ISALIVE(sc) == 0)
1653 		return (0);
1654 
1655 	if (sc->sc_mcr_rts == 0)
1656 		return (0);
1657 
1658 	s = splserial();
1659 	COM_LOCK(sc);
1660 
1661 	if (block) {
1662 		if (!ISSET(sc->sc_rx_flags, RX_TTY_BLOCKED)) {
1663 			SET(sc->sc_rx_flags, RX_TTY_BLOCKED);
1664 			com_hwiflow(sc);
1665 		}
1666 	} else {
1667 		if (ISSET(sc->sc_rx_flags, RX_TTY_OVERFLOWED)) {
1668 			CLR(sc->sc_rx_flags, RX_TTY_OVERFLOWED);
1669 			com_schedrx(sc);
1670 		}
1671 		if (ISSET(sc->sc_rx_flags, RX_TTY_BLOCKED)) {
1672 			CLR(sc->sc_rx_flags, RX_TTY_BLOCKED);
1673 			com_hwiflow(sc);
1674 		}
1675 	}
1676 
1677 	COM_UNLOCK(sc);
1678 	splx(s);
1679 	return (1);
1680 }
1681 
1682 /*
1683  * (un)block input via hw flowcontrol
1684  */
1685 void
1686 com_hwiflow(struct com_softc *sc)
1687 {
1688 	bus_space_tag_t iot = sc->sc_iot;
1689 	bus_space_handle_t ioh = sc->sc_ioh;
1690 
1691 	if (sc->sc_mcr_rts == 0)
1692 		return;
1693 
1694 	if (ISSET(sc->sc_rx_flags, RX_ANY_BLOCK)) {
1695 		CLR(sc->sc_mcr, sc->sc_mcr_rts);
1696 		CLR(sc->sc_mcr_active, sc->sc_mcr_rts);
1697 	} else {
1698 		SET(sc->sc_mcr, sc->sc_mcr_rts);
1699 		SET(sc->sc_mcr_active, sc->sc_mcr_rts);
1700 	}
1701 	bus_space_write_1(iot, ioh, com_mcr, sc->sc_mcr_active);
1702 }
1703 
1704 
1705 void
1706 comstart(struct tty *tp)
1707 {
1708 	struct com_softc *sc = device_lookup(&com_cd, COMUNIT(tp->t_dev));
1709 	bus_space_tag_t iot = sc->sc_iot;
1710 	bus_space_handle_t ioh = sc->sc_ioh;
1711 	int s;
1712 
1713 	if (COM_ISALIVE(sc) == 0)
1714 		return;
1715 
1716 	s = spltty();
1717 	if (ISSET(tp->t_state, TS_BUSY | TS_TIMEOUT | TS_TTSTOP))
1718 		goto out;
1719 	if (sc->sc_tx_stopped)
1720 		goto out;
1721 
1722 	if (tp->t_outq.c_cc <= tp->t_lowat) {
1723 		if (ISSET(tp->t_state, TS_ASLEEP)) {
1724 			CLR(tp->t_state, TS_ASLEEP);
1725 			wakeup(&tp->t_outq);
1726 		}
1727 		selwakeup(&tp->t_wsel);
1728 		if (tp->t_outq.c_cc == 0)
1729 			goto out;
1730 	}
1731 
1732 	/* Grab the first contiguous region of buffer space. */
1733 	{
1734 		u_char *tba;
1735 		int tbc;
1736 
1737 		tba = tp->t_outq.c_cf;
1738 		tbc = ndqb(&tp->t_outq, 0);
1739 
1740 		(void)splserial();
1741 		COM_LOCK(sc);
1742 
1743 		sc->sc_tba = tba;
1744 		sc->sc_tbc = tbc;
1745 	}
1746 
1747 	SET(tp->t_state, TS_BUSY);
1748 	sc->sc_tx_busy = 1;
1749 
1750 	/* Enable transmit completion interrupts if necessary. */
1751 	if (!ISSET(sc->sc_ier, IER_ETXRDY)) {
1752 		SET(sc->sc_ier, IER_ETXRDY);
1753 		bus_space_write_1(iot, ioh, com_ier, sc->sc_ier);
1754 	}
1755 
1756 	/* Output the first chunk of the contiguous buffer. */
1757 	if (!ISSET(sc->sc_hwflags, COM_HW_NO_TXPRELOAD)) {
1758 		u_int n;
1759 
1760 		n = sc->sc_tbc;
1761 		if (n > sc->sc_fifolen)
1762 			n = sc->sc_fifolen;
1763 		bus_space_write_multi_1(iot, ioh, com_data, sc->sc_tba, n);
1764 		sc->sc_tbc -= n;
1765 		sc->sc_tba += n;
1766 	}
1767 
1768 	COM_UNLOCK(sc);
1769 out:
1770 	splx(s);
1771 	return;
1772 }
1773 
1774 /*
1775  * Stop output on a line.
1776  */
1777 void
1778 comstop(struct tty *tp, int flag)
1779 {
1780 	struct com_softc *sc = device_lookup(&com_cd, COMUNIT(tp->t_dev));
1781 	int s;
1782 
1783 	s = splserial();
1784 	COM_LOCK(sc);
1785 	if (ISSET(tp->t_state, TS_BUSY)) {
1786 		/* Stop transmitting at the next chunk. */
1787 		sc->sc_tbc = 0;
1788 		sc->sc_heldtbc = 0;
1789 		if (!ISSET(tp->t_state, TS_TTSTOP))
1790 			SET(tp->t_state, TS_FLUSH);
1791 	}
1792 	COM_UNLOCK(sc);
1793 	splx(s);
1794 }
1795 
1796 void
1797 comdiag(void *arg)
1798 {
1799 	struct com_softc *sc = arg;
1800 	int overflows, floods;
1801 	int s;
1802 
1803 	s = splserial();
1804 	COM_LOCK(sc);
1805 	overflows = sc->sc_overflows;
1806 	sc->sc_overflows = 0;
1807 	floods = sc->sc_floods;
1808 	sc->sc_floods = 0;
1809 	sc->sc_errors = 0;
1810 	COM_UNLOCK(sc);
1811 	splx(s);
1812 
1813 	log(LOG_WARNING, "%s: %d silo overflow%s, %d ibuf flood%s\n",
1814 	    sc->sc_dev.dv_xname,
1815 	    overflows, overflows == 1 ? "" : "s",
1816 	    floods, floods == 1 ? "" : "s");
1817 }
1818 
1819 integrate void
1820 com_rxsoft(struct com_softc *sc, struct tty *tp)
1821 {
1822 	int (*rint)(int, struct tty *) = tp->t_linesw->l_rint;
1823 	u_char *get, *end;
1824 	u_int cc, scc;
1825 	u_char lsr;
1826 	int code;
1827 	int s;
1828 
1829 	end = sc->sc_ebuf;
1830 	get = sc->sc_rbget;
1831 	scc = cc = com_rbuf_size - sc->sc_rbavail;
1832 
1833 	if (cc == com_rbuf_size) {
1834 		sc->sc_floods++;
1835 		if (sc->sc_errors++ == 0)
1836 			callout_reset(&sc->sc_diag_callout, 60 * hz,
1837 			    comdiag, sc);
1838 	}
1839 
1840 	/* If not yet open, drop the entire buffer content here */
1841 	if (!ISSET(tp->t_state, TS_ISOPEN)) {
1842 		get += cc << 1;
1843 		if (get >= end)
1844 			get -= com_rbuf_size << 1;
1845 		cc = 0;
1846 	}
1847 	while (cc) {
1848 		code = get[0];
1849 		lsr = get[1];
1850 		if (ISSET(lsr, LSR_OE | LSR_BI | LSR_FE | LSR_PE)) {
1851 			if (ISSET(lsr, LSR_OE)) {
1852 				sc->sc_overflows++;
1853 				if (sc->sc_errors++ == 0)
1854 					callout_reset(&sc->sc_diag_callout,
1855 					    60 * hz, comdiag, sc);
1856 			}
1857 			if (ISSET(lsr, LSR_BI | LSR_FE))
1858 				SET(code, TTY_FE);
1859 			if (ISSET(lsr, LSR_PE))
1860 				SET(code, TTY_PE);
1861 		}
1862 		if ((*rint)(code, tp) == -1) {
1863 			/*
1864 			 * The line discipline's buffer is out of space.
1865 			 */
1866 			if (!ISSET(sc->sc_rx_flags, RX_TTY_BLOCKED)) {
1867 				/*
1868 				 * We're either not using flow control, or the
1869 				 * line discipline didn't tell us to block for
1870 				 * some reason.  Either way, we have no way to
1871 				 * know when there's more space available, so
1872 				 * just drop the rest of the data.
1873 				 */
1874 				get += cc << 1;
1875 				if (get >= end)
1876 					get -= com_rbuf_size << 1;
1877 				cc = 0;
1878 			} else {
1879 				/*
1880 				 * Don't schedule any more receive processing
1881 				 * until the line discipline tells us there's
1882 				 * space available (through comhwiflow()).
1883 				 * Leave the rest of the data in the input
1884 				 * buffer.
1885 				 */
1886 				SET(sc->sc_rx_flags, RX_TTY_OVERFLOWED);
1887 			}
1888 			break;
1889 		}
1890 		get += 2;
1891 		if (get >= end)
1892 			get = sc->sc_rbuf;
1893 		cc--;
1894 	}
1895 
1896 	if (cc != scc) {
1897 		sc->sc_rbget = get;
1898 		s = splserial();
1899 		COM_LOCK(sc);
1900 
1901 		cc = sc->sc_rbavail += scc - cc;
1902 		/* Buffers should be ok again, release possible block. */
1903 		if (cc >= sc->sc_r_lowat) {
1904 			if (ISSET(sc->sc_rx_flags, RX_IBUF_OVERFLOWED)) {
1905 				CLR(sc->sc_rx_flags, RX_IBUF_OVERFLOWED);
1906 				SET(sc->sc_ier, IER_ERXRDY);
1907 #ifdef COM_PXA2X0
1908 				if (sc->sc_type == COM_TYPE_PXA2x0)
1909 					SET(sc->sc_ier, IER_ERXTOUT);
1910 #endif
1911 				bus_space_write_1(sc->sc_iot, sc->sc_ioh,
1912 				    com_ier, sc->sc_ier);
1913 			}
1914 			if (ISSET(sc->sc_rx_flags, RX_IBUF_BLOCKED)) {
1915 				CLR(sc->sc_rx_flags, RX_IBUF_BLOCKED);
1916 				com_hwiflow(sc);
1917 			}
1918 		}
1919 		COM_UNLOCK(sc);
1920 		splx(s);
1921 	}
1922 }
1923 
1924 integrate void
1925 com_txsoft(struct com_softc *sc, struct tty *tp)
1926 {
1927 
1928 	CLR(tp->t_state, TS_BUSY);
1929 	if (ISSET(tp->t_state, TS_FLUSH))
1930 		CLR(tp->t_state, TS_FLUSH);
1931 	else
1932 		ndflush(&tp->t_outq, (int)(sc->sc_tba - tp->t_outq.c_cf));
1933 	(*tp->t_linesw->l_start)(tp);
1934 }
1935 
1936 integrate void
1937 com_stsoft(struct com_softc *sc, struct tty *tp)
1938 {
1939 	u_char msr, delta;
1940 	int s;
1941 
1942 	s = splserial();
1943 	COM_LOCK(sc);
1944 	msr = sc->sc_msr;
1945 	delta = sc->sc_msr_delta;
1946 	sc->sc_msr_delta = 0;
1947 	COM_UNLOCK(sc);
1948 	splx(s);
1949 
1950 	if (ISSET(delta, sc->sc_msr_dcd)) {
1951 		/*
1952 		 * Inform the tty layer that carrier detect changed.
1953 		 */
1954 		(void) (*tp->t_linesw->l_modem)(tp, ISSET(msr, MSR_DCD));
1955 	}
1956 
1957 	if (ISSET(delta, sc->sc_msr_cts)) {
1958 		/* Block or unblock output according to flow control. */
1959 		if (ISSET(msr, sc->sc_msr_cts)) {
1960 			sc->sc_tx_stopped = 0;
1961 			(*tp->t_linesw->l_start)(tp);
1962 		} else {
1963 			sc->sc_tx_stopped = 1;
1964 		}
1965 	}
1966 
1967 #ifdef COM_DEBUG
1968 	if (com_debug)
1969 		comstatus(sc, "com_stsoft");
1970 #endif
1971 }
1972 
1973 #ifdef __HAVE_GENERIC_SOFT_INTERRUPTS
1974 void
1975 comsoft(void *arg)
1976 {
1977 	struct com_softc *sc = arg;
1978 	struct tty *tp;
1979 
1980 	if (COM_ISALIVE(sc) == 0)
1981 		return;
1982 
1983 	{
1984 #else
1985 void
1986 #ifndef __NO_SOFT_SERIAL_INTERRUPT
1987 comsoft(void)
1988 #else
1989 comsoft(void *arg)
1990 #endif
1991 {
1992 	struct com_softc	*sc;
1993 	struct tty	*tp;
1994 	int	unit;
1995 #ifdef __NO_SOFT_SERIAL_INTERRUPT
1996 	int s;
1997 
1998 	s = splsoftserial();
1999 	com_softintr_scheduled = 0;
2000 #endif
2001 
2002 	for (unit = 0; unit < com_cd.cd_ndevs; unit++) {
2003 		sc = device_lookup(&com_cd, unit);
2004 		if (sc == NULL || !ISSET(sc->sc_hwflags, COM_HW_DEV_OK))
2005 			continue;
2006 
2007 		if (COM_ISALIVE(sc) == 0)
2008 			continue;
2009 
2010 		tp = sc->sc_tty;
2011 		if (tp == NULL)
2012 			continue;
2013 		if (!ISSET(tp->t_state, TS_ISOPEN) && tp->t_wopen == 0)
2014 			continue;
2015 #endif
2016 		tp = sc->sc_tty;
2017 
2018 		if (sc->sc_rx_ready) {
2019 			sc->sc_rx_ready = 0;
2020 			com_rxsoft(sc, tp);
2021 		}
2022 
2023 		if (sc->sc_st_check) {
2024 			sc->sc_st_check = 0;
2025 			com_stsoft(sc, tp);
2026 		}
2027 
2028 		if (sc->sc_tx_done) {
2029 			sc->sc_tx_done = 0;
2030 			com_txsoft(sc, tp);
2031 		}
2032 	}
2033 
2034 #ifndef __HAVE_GENERIC_SOFT_INTERRUPTS
2035 #ifdef __NO_SOFT_SERIAL_INTERRUPT
2036 	splx(s);
2037 #endif
2038 #endif
2039 }
2040 
2041 #ifdef __ALIGN_BRACKET_LEVEL_FOR_CTAGS
2042 	/* there has got to be a better way to do comsoft() */
2043 }}
2044 #endif
2045 
2046 int
2047 comintr(void *arg)
2048 {
2049 	struct com_softc *sc = arg;
2050 	bus_space_tag_t iot = sc->sc_iot;
2051 	bus_space_handle_t ioh = sc->sc_ioh;
2052 	u_char *put, *end;
2053 	u_int cc;
2054 	u_char lsr, iir;
2055 
2056 	if (COM_ISALIVE(sc) == 0)
2057 		return (0);
2058 
2059 	COM_LOCK(sc);
2060 	iir = bus_space_read_1(iot, ioh, com_iir);
2061 	if (ISSET(iir, IIR_NOPEND)) {
2062 		COM_UNLOCK(sc);
2063 		return (0);
2064 	}
2065 
2066 	end = sc->sc_ebuf;
2067 	put = sc->sc_rbput;
2068 	cc = sc->sc_rbavail;
2069 
2070 again:	do {
2071 		u_char	msr, delta;
2072 
2073 		lsr = bus_space_read_1(iot, ioh, com_lsr);
2074 		if (ISSET(lsr, LSR_BI)) {
2075 			int cn_trapped = 0;
2076 
2077 			cn_check_magic(sc->sc_tty->t_dev,
2078 				       CNC_BREAK, com_cnm_state);
2079 			if (cn_trapped)
2080 				continue;
2081 #if defined(KGDB) && !defined(DDB)
2082 			if (ISSET(sc->sc_hwflags, COM_HW_KGDB)) {
2083 				kgdb_connect(1);
2084 				continue;
2085 			}
2086 #endif
2087 		}
2088 
2089 		if (ISSET(lsr, LSR_RCV_MASK) &&
2090 		    !ISSET(sc->sc_rx_flags, RX_IBUF_OVERFLOWED)) {
2091 			while (cc > 0) {
2092 				int cn_trapped = 0;
2093 				put[0] = bus_space_read_1(iot, ioh, com_data);
2094 				put[1] = lsr;
2095 				cn_check_magic(sc->sc_tty->t_dev,
2096 					       put[0], com_cnm_state);
2097 				if (cn_trapped)
2098 					goto next;
2099 				put += 2;
2100 				if (put >= end)
2101 					put = sc->sc_rbuf;
2102 				cc--;
2103 			next:
2104 				lsr = bus_space_read_1(iot, ioh, com_lsr);
2105 				if (!ISSET(lsr, LSR_RCV_MASK))
2106 					break;
2107 			}
2108 
2109 			/*
2110 			 * Current string of incoming characters ended because
2111 			 * no more data was available or we ran out of space.
2112 			 * Schedule a receive event if any data was received.
2113 			 * If we're out of space, turn off receive interrupts.
2114 			 */
2115 			sc->sc_rbput = put;
2116 			sc->sc_rbavail = cc;
2117 			if (!ISSET(sc->sc_rx_flags, RX_TTY_OVERFLOWED))
2118 				sc->sc_rx_ready = 1;
2119 
2120 			/*
2121 			 * See if we are in danger of overflowing a buffer. If
2122 			 * so, use hardware flow control to ease the pressure.
2123 			 */
2124 			if (!ISSET(sc->sc_rx_flags, RX_IBUF_BLOCKED) &&
2125 			    cc < sc->sc_r_hiwat) {
2126 				SET(sc->sc_rx_flags, RX_IBUF_BLOCKED);
2127 				com_hwiflow(sc);
2128 			}
2129 
2130 			/*
2131 			 * If we're out of space, disable receive interrupts
2132 			 * until the queue has drained a bit.
2133 			 */
2134 			if (!cc) {
2135 				SET(sc->sc_rx_flags, RX_IBUF_OVERFLOWED);
2136 #ifdef COM_PXA2X0
2137 				if (sc->sc_type == COM_TYPE_PXA2x0)
2138 					CLR(sc->sc_ier, IER_ERXRDY|IER_ERXTOUT);
2139 				else
2140 #endif
2141 					CLR(sc->sc_ier, IER_ERXRDY);
2142 				bus_space_write_1(iot, ioh, com_ier,
2143 				    sc->sc_ier);
2144 			}
2145 		} else {
2146 			if ((iir & (IIR_RXRDY|IIR_TXRDY)) == IIR_RXRDY) {
2147 				(void) bus_space_read_1(iot, ioh, com_data);
2148 				continue;
2149 			}
2150 		}
2151 
2152 		msr = bus_space_read_1(iot, ioh, com_msr);
2153 		delta = msr ^ sc->sc_msr;
2154 		sc->sc_msr = msr;
2155 		/*
2156 		 * Pulse-per-second (PSS) signals on edge of DCD?
2157 		 * Process these even if line discipline is ignoring DCD.
2158 		 */
2159 		if (delta & sc->sc_ppsmask) {
2160 			struct timeval tv;
2161 		    	if ((msr & sc->sc_ppsmask) == sc->sc_ppsassert) {
2162 				/* XXX nanotime() */
2163 				microtime(&tv);
2164 				TIMEVAL_TO_TIMESPEC(&tv,
2165 				    &sc->ppsinfo.assert_timestamp);
2166 				if (sc->ppsparam.mode & PPS_OFFSETASSERT) {
2167 					timespecadd(&sc->ppsinfo.assert_timestamp,
2168 					    &sc->ppsparam.assert_offset,
2169 						    &sc->ppsinfo.assert_timestamp);
2170 				}
2171 
2172 #ifdef PPS_SYNC
2173 				if (pps_kc_hardpps_source == sc &&
2174 				    pps_kc_hardpps_mode & PPS_CAPTUREASSERT) {
2175 					hardpps(&tv, tv.tv_usec);
2176 				}
2177 #endif
2178 				sc->ppsinfo.assert_sequence++;
2179 				sc->ppsinfo.current_mode = sc->ppsparam.mode;
2180 
2181 			} else if ((msr & sc->sc_ppsmask) == sc->sc_ppsclear) {
2182 				/* XXX nanotime() */
2183 				microtime(&tv);
2184 				TIMEVAL_TO_TIMESPEC(&tv,
2185 				    &sc->ppsinfo.clear_timestamp);
2186 				if (sc->ppsparam.mode & PPS_OFFSETCLEAR) {
2187 					timespecadd(&sc->ppsinfo.clear_timestamp,
2188 					    &sc->ppsparam.clear_offset,
2189 					    &sc->ppsinfo.clear_timestamp);
2190 				}
2191 
2192 #ifdef PPS_SYNC
2193 				if (pps_kc_hardpps_source == sc &&
2194 				    pps_kc_hardpps_mode & PPS_CAPTURECLEAR) {
2195 					hardpps(&tv, tv.tv_usec);
2196 				}
2197 #endif
2198 				sc->ppsinfo.clear_sequence++;
2199 				sc->ppsinfo.current_mode = sc->ppsparam.mode;
2200 			}
2201 		}
2202 
2203 		/*
2204 		 * Process normal status changes
2205 		 */
2206 		if (ISSET(delta, sc->sc_msr_mask)) {
2207 			SET(sc->sc_msr_delta, delta);
2208 
2209 			/*
2210 			 * Stop output immediately if we lose the output
2211 			 * flow control signal or carrier detect.
2212 			 */
2213 			if (ISSET(~msr, sc->sc_msr_mask)) {
2214 				sc->sc_tbc = 0;
2215 				sc->sc_heldtbc = 0;
2216 #ifdef COM_DEBUG
2217 				if (com_debug)
2218 					comstatus(sc, "comintr  ");
2219 #endif
2220 			}
2221 
2222 			sc->sc_st_check = 1;
2223 		}
2224 	} while (!ISSET((iir =
2225 	    bus_space_read_1(iot, ioh, com_iir)), IIR_NOPEND) &&
2226 	    /*
2227 	     * Since some device (e.g., ST16C1550) doesn't clear IIR_TXRDY
2228 	     * by IIR read, so we can't do this way: `process all interrupts,
2229 	     * then do TX if possble'.
2230 	     */
2231 	    (iir & IIR_IMASK) != IIR_TXRDY);
2232 
2233 	/*
2234 	 * Read LSR again, since there may be an interrupt between
2235 	 * the last LSR read and IIR read above.
2236 	 */
2237 	lsr = bus_space_read_1(iot, ioh, com_lsr);
2238 
2239 	/*
2240 	 * See if data can be transmitted as well.
2241 	 * Schedule tx done event if no data left
2242 	 * and tty was marked busy.
2243 	 */
2244 	if (ISSET(lsr, LSR_TXRDY)) {
2245 		/*
2246 		 * If we've delayed a parameter change, do it now, and restart
2247 		 * output.
2248 		 */
2249 		if (sc->sc_heldchange) {
2250 			com_loadchannelregs(sc);
2251 			sc->sc_heldchange = 0;
2252 			sc->sc_tbc = sc->sc_heldtbc;
2253 			sc->sc_heldtbc = 0;
2254 		}
2255 
2256 		/* Output the next chunk of the contiguous buffer, if any. */
2257 		if (sc->sc_tbc > 0) {
2258 			u_int n;
2259 
2260 			n = sc->sc_tbc;
2261 			if (n > sc->sc_fifolen)
2262 				n = sc->sc_fifolen;
2263 			bus_space_write_multi_1(iot, ioh, com_data, sc->sc_tba, n);
2264 			sc->sc_tbc -= n;
2265 			sc->sc_tba += n;
2266 		} else {
2267 			/* Disable transmit completion interrupts if necessary. */
2268 			if (ISSET(sc->sc_ier, IER_ETXRDY)) {
2269 				CLR(sc->sc_ier, IER_ETXRDY);
2270 				bus_space_write_1(iot, ioh, com_ier, sc->sc_ier);
2271 			}
2272 			if (sc->sc_tx_busy) {
2273 				sc->sc_tx_busy = 0;
2274 				sc->sc_tx_done = 1;
2275 			}
2276 		}
2277 	}
2278 
2279 	if (!ISSET((iir = bus_space_read_1(iot, ioh, com_iir)), IIR_NOPEND))
2280 		goto again;
2281 
2282 	COM_UNLOCK(sc);
2283 
2284 	/* Wake up the poller. */
2285 #ifdef __HAVE_GENERIC_SOFT_INTERRUPTS
2286 	softintr_schedule(sc->sc_si);
2287 #else
2288 #ifndef __NO_SOFT_SERIAL_INTERRUPT
2289 	setsoftserial();
2290 #else
2291 	if (!com_softintr_scheduled) {
2292 		com_softintr_scheduled = 1;
2293 		callout_reset(&comsoft_callout, 1, comsoft, NULL);
2294 	}
2295 #endif
2296 #endif
2297 
2298 #if NRND > 0 && defined(RND_COM)
2299 	rnd_add_uint32(&sc->rnd_source, iir | lsr);
2300 #endif
2301 
2302 	return (1);
2303 }
2304 
2305 /*
2306  * The following functions are polled getc and putc routines, shared
2307  * by the console and kgdb glue.
2308  *
2309  * The read-ahead code is so that you can detect pending in-band
2310  * cn_magic in polled mode while doing output rather than having to
2311  * wait until the kernel decides it needs input.
2312  */
2313 
2314 #define MAX_READAHEAD	20
2315 static int com_readahead[MAX_READAHEAD];
2316 static int com_readaheadcount = 0;
2317 
2318 int
2319 com_common_getc(dev_t dev, bus_space_tag_t iot, bus_space_handle_t ioh)
2320 {
2321 	int s = splserial();
2322 	u_char stat, c;
2323 
2324 	/* got a character from reading things earlier */
2325 	if (com_readaheadcount > 0) {
2326 		int i;
2327 
2328 		c = com_readahead[0];
2329 		for (i = 1; i < com_readaheadcount; i++) {
2330 			com_readahead[i-1] = com_readahead[i];
2331 		}
2332 		com_readaheadcount--;
2333 		splx(s);
2334 		return (c);
2335 	}
2336 
2337 	/* block until a character becomes available */
2338 	while (!ISSET(stat = bus_space_read_1(iot, ioh, com_lsr), LSR_RXRDY))
2339 		;
2340 
2341 	c = bus_space_read_1(iot, ioh, com_data);
2342 	stat = bus_space_read_1(iot, ioh, com_iir);
2343 	{
2344 		int cn_trapped = 0; /* unused */
2345 #ifdef DDB
2346 		extern int db_active;
2347 		if (!db_active)
2348 #endif
2349 			cn_check_magic(dev, c, com_cnm_state);
2350 	}
2351 	splx(s);
2352 	return (c);
2353 }
2354 
2355 void
2356 com_common_putc(dev_t dev, bus_space_tag_t iot, bus_space_handle_t ioh, int c)
2357 {
2358 	int s = splserial();
2359 	int cin, stat, timo;
2360 
2361 	if (com_readaheadcount < MAX_READAHEAD
2362 	     && ISSET(stat = bus_space_read_1(iot, ioh, com_lsr), LSR_RXRDY)) {
2363 		int cn_trapped = 0;
2364 		cin = bus_space_read_1(iot, ioh, com_data);
2365 		stat = bus_space_read_1(iot, ioh, com_iir);
2366 		cn_check_magic(dev, cin, com_cnm_state);
2367 		com_readahead[com_readaheadcount++] = cin;
2368 	}
2369 
2370 	/* wait for any pending transmission to finish */
2371 	timo = 150000;
2372 	while (!ISSET(bus_space_read_1(iot, ioh, com_lsr), LSR_TXRDY) && --timo)
2373 		continue;
2374 
2375 	bus_space_write_1(iot, ioh, com_data, c);
2376 	COM_BARRIER(iot, ioh, BR | BW);
2377 
2378 	splx(s);
2379 }
2380 
2381 /*
2382  * Initialize UART for use as console or KGDB line.
2383  */
2384 int
2385 cominit(bus_space_tag_t iot, bus_addr_t iobase, int rate, int frequency,
2386     int type, tcflag_t cflag, bus_space_handle_t *iohp)
2387 {
2388 	bus_space_handle_t ioh;
2389 
2390 	if (bus_space_map(iot, iobase, COM_NPORTS, 0, &ioh))
2391 		return (ENOMEM); /* ??? */
2392 
2393 	bus_space_write_1(iot, ioh, com_lcr, LCR_EERS);
2394 	bus_space_write_1(iot, ioh, com_efr, 0);
2395 	bus_space_write_1(iot, ioh, com_lcr, LCR_DLAB);
2396 	rate = comspeed(rate, frequency, type);
2397 	bus_space_write_1(iot, ioh, com_dlbl, rate);
2398 	bus_space_write_1(iot, ioh, com_dlbh, rate >> 8);
2399 	bus_space_write_1(iot, ioh, com_lcr, cflag2lcr(cflag));
2400 	bus_space_write_1(iot, ioh, com_mcr, MCR_DTR | MCR_RTS);
2401 	bus_space_write_1(iot, ioh, com_fifo,
2402 	    FIFO_ENABLE | FIFO_RCV_RST | FIFO_XMT_RST | FIFO_TRIGGER_1);
2403 #ifdef COM_PXA2X0
2404 	if (type == COM_TYPE_PXA2x0)
2405 		bus_space_write_1(iot, ioh, com_ier, IER_EUART);
2406 	else
2407 #endif
2408 		bus_space_write_1(iot, ioh, com_ier, 0);
2409 
2410 	*iohp = ioh;
2411 	return (0);
2412 }
2413 
2414 /*
2415  * Following are all routines needed for COM to act as console
2416  */
2417 struct consdev comcons = {
2418 	NULL, NULL, comcngetc, comcnputc, comcnpollc, NULL, NULL, NULL,
2419 	NODEV, CN_NORMAL
2420 };
2421 
2422 
2423 int
2424 comcnattach(bus_space_tag_t iot, bus_addr_t iobase, int rate, int frequency,
2425     int type, tcflag_t cflag)
2426 {
2427 	int res;
2428 
2429 	res = cominit(iot, iobase, rate, frequency, type, cflag, &comconsioh);
2430 	if (res)
2431 		return (res);
2432 
2433 	cn_tab = &comcons;
2434 	cn_init_magic(&com_cnm_state);
2435 	cn_set_magic("\047\001"); /* default magic is BREAK */
2436 
2437 	comconstag = iot;
2438 	comconsaddr = iobase;
2439 	comconsrate = rate;
2440 	comconscflag = cflag;
2441 
2442 	return (0);
2443 }
2444 
2445 int
2446 comcngetc(dev_t dev)
2447 {
2448 
2449 	return (com_common_getc(dev, comconstag, comconsioh));
2450 }
2451 
2452 /*
2453  * Console kernel output character routine.
2454  */
2455 void
2456 comcnputc(dev_t dev, int c)
2457 {
2458 
2459 	com_common_putc(dev, comconstag, comconsioh, c);
2460 }
2461 
2462 void
2463 comcnpollc(dev_t dev, int on)
2464 {
2465 
2466 }
2467 
2468 #ifdef KGDB
2469 int
2470 com_kgdb_attach(bus_space_tag_t iot, bus_addr_t iobase, int rate,
2471     int frequency, int type, tcflag_t cflag)
2472 {
2473 	int res;
2474 
2475 	if (iot == comconstag && iobase == comconsaddr) {
2476 #if !defined(DDB)
2477 		return (EBUSY); /* cannot share with console */
2478 #else
2479 		com_kgdb_ioh = comconsioh;
2480 #endif
2481 	} else {
2482 		res = cominit(iot, iobase, rate, frequency, type, cflag,
2483 			      &com_kgdb_ioh);
2484 		if (res)
2485 			return (res);
2486 
2487 		/*
2488 		 * XXXfvdl this shouldn't be needed, but the cn_magic goo
2489 		 * expects this to be initialized
2490 		 */
2491 		cn_init_magic(&com_cnm_state);
2492 		cn_set_magic("\047\001");
2493 	}
2494 
2495 	kgdb_attach(com_kgdb_getc, com_kgdb_putc, NULL);
2496 	kgdb_dev = 123; /* unneeded, only to satisfy some tests */
2497 
2498 	com_kgdb_iot = iot;
2499 	com_kgdb_addr = iobase;
2500 
2501 	return (0);
2502 }
2503 
2504 /* ARGSUSED */
2505 int
2506 com_kgdb_getc(void *arg)
2507 {
2508 
2509 	return (com_common_getc(NODEV, com_kgdb_iot, com_kgdb_ioh));
2510 }
2511 
2512 /* ARGSUSED */
2513 void
2514 com_kgdb_putc(void *arg, int c)
2515 {
2516 
2517 	com_common_putc(NODEV, com_kgdb_iot, com_kgdb_ioh, c);
2518 }
2519 #endif /* KGDB */
2520 
2521 /* helper function to identify the com ports used by
2522  console or KGDB (and not yet autoconf attached) */
2523 int
2524 com_is_console(bus_space_tag_t iot, bus_addr_t iobase, bus_space_handle_t *ioh)
2525 {
2526 	bus_space_handle_t help;
2527 
2528 	if (!comconsattached &&
2529 	    iot == comconstag && iobase == comconsaddr)
2530 		help = comconsioh;
2531 #ifdef KGDB
2532 	else if (!com_kgdb_attached &&
2533 	    iot == com_kgdb_iot && iobase == com_kgdb_addr)
2534 		help = com_kgdb_ioh;
2535 #endif
2536 	else
2537 		return (0);
2538 
2539 	if (ioh)
2540 		*ioh = help;
2541 	return (1);
2542 }
2543