xref: /netbsd-src/sys/dev/ic/com.c (revision bcc8ec9959e7b01e313d813067bfb43a3ad70551)
1 /*	$NetBSD: com.c,v 1.183 2001/01/14 23:50:28 thorpej Exp $	*/
2 
3 /*-
4  * Copyright (c) 1998, 1999 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. All advertising materials mentioning features or use of this software
52  *    must display the following acknowledgement:
53  *	This product includes software developed by the University of
54  *	California, Berkeley and its contributors.
55  * 4. Neither the name of the University nor the names of its contributors
56  *    may be used to endorse or promote products derived from this software
57  *    without specific prior written permission.
58  *
59  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
60  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
61  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
62  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
63  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
64  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
65  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
66  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
67  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
68  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
69  * SUCH DAMAGE.
70  *
71  *	@(#)com.c	7.5 (Berkeley) 5/16/91
72  */
73 
74 #if defined(__sparc__) || defined(__sparc_v9__)
75 #define	DDB_BREAK_CHAR	1	/* L1 or Stop key */
76 #endif
77 
78 /*
79  * COM driver, uses National Semiconductor NS16450/NS16550AF UART
80  * Supports automatic hardware flow control on StarTech ST16C650A UART
81  */
82 
83 #include "opt_ddb.h"
84 #include "opt_ddbparam.h"
85 #include "opt_com.h"
86 
87 #include "rnd.h"
88 #if NRND > 0 && defined(RND_COM)
89 #include <sys/rnd.h>
90 #endif
91 
92 #include <sys/param.h>
93 #include <sys/systm.h>
94 #include <sys/ioctl.h>
95 #include <sys/select.h>
96 #include <sys/tty.h>
97 #include <sys/proc.h>
98 #include <sys/user.h>
99 #include <sys/conf.h>
100 #include <sys/file.h>
101 #include <sys/uio.h>
102 #include <sys/kernel.h>
103 #include <sys/syslog.h>
104 #include <sys/types.h>
105 #include <sys/device.h>
106 #include <sys/malloc.h>
107 #include <sys/timepps.h>
108 #include <sys/vnode.h>
109 
110 #include <machine/intr.h>
111 #include <machine/bus.h>
112 
113 #include <dev/ic/comreg.h>
114 #include <dev/ic/comvar.h>
115 #include <dev/ic/ns16550reg.h>
116 #include <dev/ic/st16650reg.h>
117 #ifdef COM_HAYESP
118 #include <dev/ic/hayespreg.h>
119 #endif
120 #define	com_lcr	com_cfcr
121 #include <dev/cons.h>
122 
123 #include "com.h"
124 
125 #ifdef COM_HAYESP
126 int comprobeHAYESP __P((bus_space_handle_t hayespioh, struct com_softc *sc));
127 #endif
128 
129 #if defined(DDB) || defined(KGDB)
130 static void com_enable_debugport __P((struct com_softc *));
131 #endif
132 void	com_config	__P((struct com_softc *));
133 void	com_shutdown	__P((struct com_softc *));
134 int	comspeed	__P((long, long));
135 static	u_char	cflag2lcr __P((tcflag_t));
136 int	comparam	__P((struct tty *, struct termios *));
137 void	comstart	__P((struct tty *));
138 void	comstop		__P((struct tty *, int));
139 int	comhwiflow	__P((struct tty *, int));
140 
141 void	com_loadchannelregs __P((struct com_softc *));
142 void	com_hwiflow	__P((struct com_softc *));
143 void	com_break	__P((struct com_softc *, int));
144 void	com_modem	__P((struct com_softc *, int));
145 void	tiocm_to_com	__P((struct com_softc *, u_long, int));
146 int	com_to_tiocm	__P((struct com_softc *));
147 void	com_iflush	__P((struct com_softc *));
148 
149 int	com_common_getc	__P((bus_space_tag_t, bus_space_handle_t));
150 void	com_common_putc	__P((bus_space_tag_t, bus_space_handle_t, int));
151 
152 /* XXX: These belong elsewhere */
153 cdev_decl(com);
154 bdev_decl(com);
155 
156 int	comcngetc	__P((dev_t));
157 void	comcnputc	__P((dev_t, int));
158 void	comcnpollc	__P((dev_t, int));
159 
160 #define	integrate	static inline
161 #ifdef __HAVE_GENERIC_SOFT_INTERRUPTS
162 void 	comsoft		__P((void *));
163 #else
164 #ifndef __NO_SOFT_SERIAL_INTERRUPT
165 void 	comsoft		__P((void));
166 #else
167 void 	comsoft		__P((void *));
168 struct callout comsoft_callout = CALLOUT_INITIALIZER;
169 #endif
170 #endif
171 integrate void com_rxsoft	__P((struct com_softc *, struct tty *));
172 integrate void com_txsoft	__P((struct com_softc *, struct tty *));
173 integrate void com_stsoft	__P((struct com_softc *, struct tty *));
174 integrate void com_schedrx	__P((struct com_softc *));
175 void	comdiag		__P((void *));
176 
177 extern struct cfdriver com_cd;
178 
179 /*
180  * Make this an option variable one can patch.
181  * But be warned:  this must be a power of 2!
182  */
183 u_int com_rbuf_size = COM_RING_SIZE;
184 
185 /* Stop input when 3/4 of the ring is full; restart when only 1/4 is full. */
186 u_int com_rbuf_hiwat = (COM_RING_SIZE * 1) / 4;
187 u_int com_rbuf_lowat = (COM_RING_SIZE * 3) / 4;
188 
189 static bus_addr_t	comconsaddr;
190 static bus_space_tag_t comconstag;
191 static bus_space_handle_t comconsioh;
192 static int	comconsattached;
193 static int comconsrate;
194 static tcflag_t comconscflag;
195 
196 static int ppscap =
197 	PPS_TSFMT_TSPEC |
198 	PPS_CAPTUREASSERT |
199 	PPS_CAPTURECLEAR |
200 #ifdef  PPS_SYNC
201 	PPS_HARDPPSONASSERT | PPS_HARDPPSONCLEAR |
202 #endif	/* PPS_SYNC */
203 	PPS_OFFSETASSERT | PPS_OFFSETCLEAR;
204 
205 #ifndef __HAVE_GENERIC_SOFT_INTERRUPTS
206 #ifdef __NO_SOFT_SERIAL_INTERRUPT
207 volatile int	com_softintr_scheduled;
208 #endif
209 #endif
210 
211 #ifdef KGDB
212 #include <sys/kgdb.h>
213 
214 static bus_addr_t com_kgdb_addr;
215 static bus_space_tag_t com_kgdb_iot;
216 static bus_space_handle_t com_kgdb_ioh;
217 static int com_kgdb_attached;
218 
219 int	com_kgdb_getc __P((void *));
220 void	com_kgdb_putc __P((void *, int));
221 #endif /* KGDB */
222 
223 #define	COMUNIT_MASK	0x7ffff
224 #define	COMDIALOUT_MASK	0x80000
225 
226 #define	COMUNIT(x)	(minor(x) & COMUNIT_MASK)
227 #define	COMDIALOUT(x)	(minor(x) & COMDIALOUT_MASK)
228 
229 #define	COM_ISALIVE(sc)	((sc)->enabled != 0 && \
230 			 ISSET((sc)->sc_dev.dv_flags, DVF_ACTIVE))
231 
232 #define	BR	BUS_SPACE_BARRIER_READ
233 #define	BW	BUS_SPACE_BARRIER_WRITE
234 #define COM_BARRIER(t, h, f) bus_space_barrier((t), (h), 0, COM_NPORTS, (f))
235 
236 #if (defined(MULTIPROCESSOR) || defined(LOCKDEBUG)) && defined(COM_MPLOCK)
237 
238 #define COM_LOCK(sc) simple_lock(&(sc)->sc_lock)
239 #define COM_UNLOCK(sc) simple_unlock(&(sc)->sc_lock)
240 
241 #else
242 
243 #define COM_LOCK(sc)
244 #define COM_UNLOCK(sc)
245 
246 #endif
247 
248 int
249 comspeed(speed, frequency)
250 	long speed, frequency;
251 {
252 #define	divrnd(n, q)	(((n)*2/(q)+1)/2)	/* divide and round off */
253 
254 	int x, err;
255 
256 #if 0
257 	if (speed == 0)
258 		return (0);
259 #endif
260 	if (speed <= 0)
261 		return (-1);
262 	x = divrnd(frequency / 16, speed);
263 	if (x <= 0)
264 		return (-1);
265 	err = divrnd(((quad_t)frequency) * 1000 / 16, speed * x) - 1000;
266 	if (err < 0)
267 		err = -err;
268 	if (err > COM_TOLERANCE)
269 		return (-1);
270 	return (x);
271 
272 #undef	divrnd
273 }
274 
275 #ifdef COM_DEBUG
276 int	com_debug = 0;
277 
278 void comstatus __P((struct com_softc *, char *));
279 void
280 comstatus(sc, str)
281 	struct com_softc *sc;
282 	char *str;
283 {
284 	struct tty *tp = sc->sc_tty;
285 
286 	printf("%s: %s %sclocal  %sdcd %sts_carr_on %sdtr %stx_stopped\n",
287 	    sc->sc_dev.dv_xname, str,
288 	    ISSET(tp->t_cflag, CLOCAL) ? "+" : "-",
289 	    ISSET(sc->sc_msr, MSR_DCD) ? "+" : "-",
290 	    ISSET(tp->t_state, TS_CARR_ON) ? "+" : "-",
291 	    ISSET(sc->sc_mcr, MCR_DTR) ? "+" : "-",
292 	    sc->sc_tx_stopped ? "+" : "-");
293 
294 	printf("%s: %s %scrtscts %scts %sts_ttstop  %srts %xrx_flags\n",
295 	    sc->sc_dev.dv_xname, str,
296 	    ISSET(tp->t_cflag, CRTSCTS) ? "+" : "-",
297 	    ISSET(sc->sc_msr, MSR_CTS) ? "+" : "-",
298 	    ISSET(tp->t_state, TS_TTSTOP) ? "+" : "-",
299 	    ISSET(sc->sc_mcr, MCR_RTS) ? "+" : "-",
300 	    sc->sc_rx_flags);
301 }
302 #endif
303 
304 int
305 comprobe1(iot, ioh)
306 	bus_space_tag_t iot;
307 	bus_space_handle_t ioh;
308 {
309 
310 	/* force access to id reg */
311 	bus_space_write_1(iot, ioh, com_lcr, LCR_8BITS);
312 	bus_space_write_1(iot, ioh, com_iir, 0);
313 	if ((bus_space_read_1(iot, ioh, com_lcr) != LCR_8BITS) ||
314 	    (bus_space_read_1(iot, ioh, com_iir) & 0x38))
315 		return (0);
316 
317 	return (1);
318 }
319 
320 #ifdef COM_HAYESP
321 int
322 comprobeHAYESP(hayespioh, sc)
323 	bus_space_handle_t hayespioh;
324 	struct com_softc *sc;
325 {
326 	char	val, dips;
327 	int	combaselist[] = { 0x3f8, 0x2f8, 0x3e8, 0x2e8 };
328 	bus_space_tag_t iot = sc->sc_iot;
329 
330 	/*
331 	 * Hayes ESP cards have two iobases.  One is for compatibility with
332 	 * 16550 serial chips, and at the same ISA PC base addresses.  The
333 	 * other is for ESP-specific enhanced features, and lies at a
334 	 * different addressing range entirely (0x140, 0x180, 0x280, or 0x300).
335 	 */
336 
337 	/* Test for ESP signature */
338 	if ((bus_space_read_1(iot, hayespioh, 0) & 0xf3) == 0)
339 		return (0);
340 
341 	/*
342 	 * ESP is present at ESP enhanced base address; unknown com port
343 	 */
344 
345 	/* Get the dip-switch configurations */
346 	bus_space_write_1(iot, hayespioh, HAYESP_CMD1, HAYESP_GETDIPS);
347 	dips = bus_space_read_1(iot, hayespioh, HAYESP_STATUS1);
348 
349 	/* Determine which com port this ESP card services: bits 0,1 of  */
350 	/*  dips is the port # (0-3); combaselist[val] is the com_iobase */
351 	if (sc->sc_iobase != combaselist[dips & 0x03])
352 		return (0);
353 
354 	printf(": ESP");
355 
356  	/* Check ESP Self Test bits. */
357 	/* Check for ESP version 2.0: bits 4,5,6 == 010 */
358 	bus_space_write_1(iot, hayespioh, HAYESP_CMD1, HAYESP_GETTEST);
359 	val = bus_space_read_1(iot, hayespioh, HAYESP_STATUS1); /* Clear reg1 */
360 	val = bus_space_read_1(iot, hayespioh, HAYESP_STATUS2);
361 	if ((val & 0x70) < 0x20) {
362 		printf("-old (%o)", val & 0x70);
363 		/* we do not support the necessary features */
364 		return (0);
365 	}
366 
367 	/* Check for ability to emulate 16550: bit 8 == 1 */
368 	if ((dips & 0x80) == 0) {
369 		printf(" slave");
370 		/* XXX Does slave really mean no 16550 support?? */
371 		return (0);
372 	}
373 
374 	/*
375 	 * If we made it this far, we are a full-featured ESP v2.0 (or
376 	 * better), at the correct com port address.
377 	 */
378 
379 	SET(sc->sc_hwflags, COM_HW_HAYESP);
380 	printf(", 1024 byte fifo\n");
381 	return (1);
382 }
383 #endif
384 
385 #if defined(DDB) || defined(KGDB)
386 static void
387 com_enable_debugport(sc)
388 	struct com_softc *sc;
389 {
390 	int s;
391 
392 	/* Turn on line break interrupt, set carrier. */
393 	s = splserial();
394 	COM_LOCK(sc);
395 	sc->sc_ier = IER_ERXRDY;
396 	bus_space_write_1(sc->sc_iot, sc->sc_ioh, com_ier, sc->sc_ier);
397 	SET(sc->sc_mcr, MCR_DTR | MCR_RTS);
398 	bus_space_write_1(sc->sc_iot, sc->sc_ioh, com_mcr, sc->sc_mcr);
399 	COM_UNLOCK(sc);
400 	splx(s);
401 }
402 #endif
403 
404 void
405 com_attach_subr(sc)
406 	struct com_softc *sc;
407 {
408 	bus_addr_t iobase = sc->sc_iobase;
409 	bus_space_tag_t iot = sc->sc_iot;
410 	bus_space_handle_t ioh = sc->sc_ioh;
411 	struct tty *tp;
412 #ifdef COM16650
413 	u_int8_t lcr;
414 #endif
415 #ifdef COM_HAYESP
416 	int	hayesp_ports[] = { 0x140, 0x180, 0x280, 0x300, 0 };
417 	int	*hayespp;
418 #endif
419 
420 	callout_init(&sc->sc_diag_callout);
421 #if (defined(MULTIPROCESSOR) || defined(LOCKDEBUG)) && defined(COM_MPLOCK)
422 	simple_lock_init(&sc->sc_lock);
423 #endif
424 
425 	/* Disable interrupts before configuring the device. */
426 	sc->sc_ier = 0;
427 	bus_space_write_1(iot, ioh, com_ier, sc->sc_ier);
428 
429 	if (iot == comconstag && iobase == comconsaddr) {
430 		comconsattached = 1;
431 
432 		/* Make sure the console is always "hardwired". */
433 		delay(1000);			/* wait for output to finish */
434 		SET(sc->sc_hwflags, COM_HW_CONSOLE);
435 		SET(sc->sc_swflags, TIOCFLAG_SOFTCAR);
436 	}
437 
438 #ifdef COM_HAYESP
439 	/* Look for a Hayes ESP board. */
440 	for (hayespp = hayesp_ports; *hayespp != 0; hayespp++) {
441 		bus_space_handle_t hayespioh;
442 
443 #define	HAYESP_NPORTS	8			/* XXX XXX XXX ??? ??? ??? */
444 		if (bus_space_map(iot, *hayespp, HAYESP_NPORTS, 0, &hayespioh))
445 			continue;
446 		if (comprobeHAYESP(hayespioh, sc)) {
447 			sc->sc_hayespioh = hayespioh;
448 			sc->sc_fifolen = 1024;
449 
450 			break;
451 		}
452 		bus_space_unmap(iot, hayespioh, HAYESP_NPORTS);
453 	}
454 	/* No ESP; look for other things. */
455 	if (!ISSET(sc->sc_hwflags, COM_HW_HAYESP)) {
456 #endif
457 	sc->sc_fifolen = 1;
458 	/* look for a NS 16550AF UART with FIFOs */
459 	bus_space_write_1(iot, ioh, com_fifo,
460 	    FIFO_ENABLE | FIFO_RCV_RST | FIFO_XMT_RST | FIFO_TRIGGER_14);
461 	delay(100);
462 	if (ISSET(bus_space_read_1(iot, ioh, com_iir), IIR_FIFO_MASK)
463 	    == IIR_FIFO_MASK)
464 		if (ISSET(bus_space_read_1(iot, ioh, com_fifo), FIFO_TRIGGER_14)
465 		    == FIFO_TRIGGER_14) {
466 			SET(sc->sc_hwflags, COM_HW_FIFO);
467 
468 #ifdef COM16650
469 			/*
470 			 * IIR changes into the EFR if LCR is set to LCR_EERS
471 			 * on 16650s. We also know IIR != 0 at this point.
472 			 * Write 0 into the EFR, and read it. If the result
473 			 * is 0, we have a 16650.
474 			 *
475 			 * Older 16650s were broken; the test to detect them
476 			 * is taken from the Linux driver. Apparently
477 			 * setting DLAB enable gives access to the EFR on
478 			 * these chips.
479 			 */
480 			lcr = bus_space_read_1(iot, ioh, com_lcr);
481 			bus_space_write_1(iot, ioh, com_lcr, LCR_EERS);
482 			bus_space_write_1(iot, ioh, com_efr, 0);
483 			if (bus_space_read_1(iot, ioh, com_efr) == 0) {
484 				bus_space_write_1(iot, ioh, com_lcr,
485 				    lcr | LCR_DLAB);
486 				if (bus_space_read_1(iot, ioh, com_efr) == 0) {
487 					CLR(sc->sc_hwflags, COM_HW_FIFO);
488 					sc->sc_fifolen = 0;
489 				} else {
490 					SET(sc->sc_hwflags, COM_HW_FLOW);
491 					sc->sc_fifolen = 32;
492 				}
493 			} else
494 #endif
495 				sc->sc_fifolen = 16;
496 
497 #ifdef COM16650
498 			bus_space_write_1(iot, ioh, com_lcr, lcr);
499 			if (sc->sc_fifolen == 0)
500 				printf(": st16650, broken fifo\n");
501 			else if (sc->sc_fifolen == 32)
502 				printf(": st16650a, working fifo\n");
503 			else
504 #endif
505 				printf(": ns16550a, working fifo\n");
506 		} else
507 			printf(": ns16550, broken fifo\n");
508 	else
509 		printf(": ns8250 or ns16450, no fifo\n");
510 	bus_space_write_1(iot, ioh, com_fifo, 0);
511 	if (ISSET(sc->sc_hwflags, COM_HW_TXFIFO_DISABLE)) {
512 		sc->sc_fifolen = 1;
513 		printf("%s: txfifo disabled\n", sc->sc_dev.dv_xname);
514 	}
515 #ifdef COM_HAYESP
516 	}
517 #endif
518 
519 	tp = ttymalloc();
520 	tp->t_oproc = comstart;
521 	tp->t_param = comparam;
522 	tp->t_hwiflow = comhwiflow;
523 
524 	sc->sc_tty = tp;
525 	sc->sc_rbuf = malloc(com_rbuf_size << 1, M_DEVBUF, M_NOWAIT);
526 	sc->sc_rbput = sc->sc_rbget = sc->sc_rbuf;
527 	sc->sc_rbavail = com_rbuf_size;
528 	if (sc->sc_rbuf == NULL) {
529 		printf("%s: unable to allocate ring buffer\n",
530 		    sc->sc_dev.dv_xname);
531 		return;
532 	}
533 	sc->sc_ebuf = sc->sc_rbuf + (com_rbuf_size << 1);
534 
535 	tty_attach(tp);
536 
537 	if (!ISSET(sc->sc_hwflags, COM_HW_NOIEN))
538 		SET(sc->sc_mcr, MCR_IENABLE);
539 
540 	if (ISSET(sc->sc_hwflags, COM_HW_CONSOLE)) {
541 		int maj;
542 
543 		/* locate the major number */
544 		for (maj = 0; maj < nchrdev; maj++)
545 			if (cdevsw[maj].d_open == comopen)
546 				break;
547 
548 		cn_tab->cn_dev = makedev(maj, sc->sc_dev.dv_unit);
549 
550 		printf("%s: console\n", sc->sc_dev.dv_xname);
551 	}
552 
553 #ifdef KGDB
554 	/*
555 	 * Allow kgdb to "take over" this port.  If this is
556 	 * the kgdb device, it has exclusive use.
557 	 */
558 	if (iot == com_kgdb_iot && iobase == com_kgdb_addr) {
559 		com_kgdb_attached = 1;
560 
561 		SET(sc->sc_hwflags, COM_HW_KGDB);
562 		printf("%s: kgdb\n", sc->sc_dev.dv_xname);
563 	}
564 #endif
565 
566 #ifdef __HAVE_GENERIC_SOFT_INTERRUPTS
567 	sc->sc_si = softintr_establish(IPL_SOFTSERIAL, comsoft, sc);
568 #endif
569 
570 #if NRND > 0 && defined(RND_COM)
571 	rnd_attach_source(&sc->rnd_source, sc->sc_dev.dv_xname,
572 			  RND_TYPE_TTY, 0);
573 #endif
574 
575 	/* if there are no enable/disable functions, assume the device
576 	   is always enabled */
577 	if (!sc->enable)
578 		sc->enabled = 1;
579 
580 	com_config(sc);
581 
582 	SET(sc->sc_hwflags, COM_HW_DEV_OK);
583 }
584 
585 void
586 com_config(sc)
587 	struct com_softc *sc;
588 {
589 	bus_space_tag_t iot = sc->sc_iot;
590 	bus_space_handle_t ioh = sc->sc_ioh;
591 
592 	/* Disable interrupts before configuring the device. */
593 	sc->sc_ier = 0;
594 	bus_space_write_1(iot, ioh, com_ier, sc->sc_ier);
595 
596 #ifdef COM_HAYESP
597 	/* Look for a Hayes ESP board. */
598 	if (ISSET(sc->sc_hwflags, COM_HW_HAYESP)) {
599 		sc->sc_fifolen = 1024;
600 
601 		/* Set 16550 compatibility mode */
602 		bus_space_write_1(iot, sc->sc_hayespioh, HAYESP_CMD1,
603 				  HAYESP_SETMODE);
604 		bus_space_write_1(iot, sc->sc_hayespioh, HAYESP_CMD2,
605 				  HAYESP_MODE_FIFO|HAYESP_MODE_RTS|
606 				  HAYESP_MODE_SCALE);
607 
608 		/* Set RTS/CTS flow control */
609 		bus_space_write_1(iot, sc->sc_hayespioh, HAYESP_CMD1,
610 				  HAYESP_SETFLOWTYPE);
611 		bus_space_write_1(iot, sc->sc_hayespioh, HAYESP_CMD2,
612 				  HAYESP_FLOW_RTS);
613 		bus_space_write_1(iot, sc->sc_hayespioh, HAYESP_CMD2,
614 				  HAYESP_FLOW_CTS);
615 
616 		/* Set flow control levels */
617 		bus_space_write_1(iot, sc->sc_hayespioh, HAYESP_CMD1,
618 				  HAYESP_SETRXFLOW);
619 		bus_space_write_1(iot, sc->sc_hayespioh, HAYESP_CMD2,
620 				  HAYESP_HIBYTE(HAYESP_RXHIWMARK));
621 		bus_space_write_1(iot, sc->sc_hayespioh, HAYESP_CMD2,
622 				  HAYESP_LOBYTE(HAYESP_RXHIWMARK));
623 		bus_space_write_1(iot, sc->sc_hayespioh, HAYESP_CMD2,
624 				  HAYESP_HIBYTE(HAYESP_RXLOWMARK));
625 		bus_space_write_1(iot, sc->sc_hayespioh, HAYESP_CMD2,
626 				  HAYESP_LOBYTE(HAYESP_RXLOWMARK));
627 	}
628 #endif
629 
630 #ifdef DDB
631 	if (ISSET(sc->sc_hwflags, COM_HW_CONSOLE))
632 		com_enable_debugport(sc);
633 #endif
634 
635 #ifdef KGDB
636 	/*
637 	 * Allow kgdb to "take over" this port.  If this is
638 	 * the kgdb device, it has exclusive use.
639 	 */
640 	if (ISSET(sc->sc_hwflags, COM_HW_KGDB))
641 		com_enable_debugport(sc);
642 #endif
643 }
644 
645 int
646 com_detach(self, flags)
647 	struct device *self;
648 	int flags;
649 {
650 	struct com_softc *sc = (struct com_softc *)self;
651 	int maj, mn;
652 
653 	/* locate the major number */
654 	for (maj = 0; maj < nchrdev; maj++)
655 		if (cdevsw[maj].d_open == comopen)
656 			break;
657 
658 	/* Nuke the vnodes for any open instances. */
659 	mn = self->dv_unit;
660 	vdevgone(maj, mn, mn, VCHR);
661 
662 	mn |= COMDIALOUT_MASK;
663 	vdevgone(maj, mn, mn, VCHR);
664 
665 	/* Free the receive buffer. */
666 	free(sc->sc_rbuf, M_DEVBUF);
667 
668 	/* Detach and free the tty. */
669 	tty_detach(sc->sc_tty);
670 	ttyfree(sc->sc_tty);
671 
672 #ifdef __HAVE_GENERIC_SOFT_INTERRUPTS
673 	/* Unhook the soft interrupt handler. */
674 	softintr_disestablish(sc->sc_si);
675 #endif
676 
677 #if NRND > 0 && defined(RND_COM)
678 	/* Unhook the entropy source. */
679 	rnd_detach_source(&sc->rnd_source);
680 #endif
681 
682 	return (0);
683 }
684 
685 int
686 com_activate(self, act)
687 	struct device *self;
688 	enum devact act;
689 {
690 	struct com_softc *sc = (struct com_softc *)self;
691 	int s, rv = 0;
692 
693 	s = splserial();
694 	COM_LOCK(sc);
695 	switch (act) {
696 	case DVACT_ACTIVATE:
697 		rv = EOPNOTSUPP;
698 		break;
699 
700 	case DVACT_DEACTIVATE:
701 		if (sc->sc_hwflags & (COM_HW_CONSOLE|COM_HW_KGDB)) {
702 			rv = EBUSY;
703 			break;
704 		}
705 
706 		if (sc->disable != NULL && sc->enabled != 0) {
707 			(*sc->disable)(sc);
708 			sc->enabled = 0;
709 		}
710 		break;
711 	}
712 
713 	COM_UNLOCK(sc);
714 	splx(s);
715 	return (rv);
716 }
717 
718 void
719 com_shutdown(sc)
720 	struct com_softc *sc;
721 {
722 	struct tty *tp = sc->sc_tty;
723 	int s;
724 
725 	s = splserial();
726 	COM_LOCK(sc);
727 
728 	/* If we were asserting flow control, then deassert it. */
729 	SET(sc->sc_rx_flags, RX_IBUF_BLOCKED);
730 	com_hwiflow(sc);
731 
732 	/* Clear any break condition set with TIOCSBRK. */
733 	com_break(sc, 0);
734 
735 	/* Turn off PPS capture on last close. */
736 	sc->sc_ppsmask = 0;
737 	sc->ppsparam.mode = 0;
738 
739 	/*
740 	 * Hang up if necessary.  Wait a bit, so the other side has time to
741 	 * notice even if we immediately open the port again.
742 	 * Avoid tsleeping above splhigh().
743 	 */
744 	if (ISSET(tp->t_cflag, HUPCL)) {
745 		com_modem(sc, 0);
746 		COM_UNLOCK(sc);
747 		splx(s);
748 		/* XXX tsleep will only timeout */
749 		(void) tsleep(sc, TTIPRI, ttclos, hz);
750 		s = splserial();
751 		COM_LOCK(sc);
752 	}
753 
754 	/* Turn off interrupts. */
755 #ifdef DDB
756 	if (ISSET(sc->sc_hwflags, COM_HW_CONSOLE))
757 		sc->sc_ier = IER_ERXRDY; /* interrupt on break */
758 	else
759 #endif
760 		sc->sc_ier = 0;
761 	bus_space_write_1(sc->sc_iot, sc->sc_ioh, com_ier, sc->sc_ier);
762 
763 	if (sc->disable) {
764 #ifdef DIAGNOSTIC
765 		if (!sc->enabled)
766 			panic("com_shutdown: not enabled?");
767 #endif
768 		(*sc->disable)(sc);
769 		sc->enabled = 0;
770 	}
771 	COM_UNLOCK(sc);
772 	splx(s);
773 }
774 
775 int
776 comopen(dev, flag, mode, p)
777 	dev_t dev;
778 	int flag, mode;
779 	struct proc *p;
780 {
781 	struct com_softc *sc;
782 	struct tty *tp;
783 	int s, s2;
784 	int error;
785 
786 	sc = device_lookup(&com_cd, COMUNIT(dev));
787 	if (sc == NULL || !ISSET(sc->sc_hwflags, COM_HW_DEV_OK) ||
788 		sc->sc_rbuf == NULL)
789 		return (ENXIO);
790 
791 	if (ISSET(sc->sc_dev.dv_flags, DVF_ACTIVE) == 0)
792 		return (ENXIO);
793 
794 #ifdef KGDB
795 	/*
796 	 * If this is the kgdb port, no other use is permitted.
797 	 */
798 	if (ISSET(sc->sc_hwflags, COM_HW_KGDB))
799 		return (EBUSY);
800 #endif
801 
802 	tp = sc->sc_tty;
803 
804 	if (ISSET(tp->t_state, TS_ISOPEN) &&
805 	    ISSET(tp->t_state, TS_XCLUDE) &&
806 		p->p_ucred->cr_uid != 0)
807 		return (EBUSY);
808 
809 	s = spltty();
810 
811 	/*
812 	 * Do the following iff this is a first open.
813 	 */
814 	if (!ISSET(tp->t_state, TS_ISOPEN) && tp->t_wopen == 0) {
815 		struct termios t;
816 
817 		tp->t_dev = dev;
818 
819 		s2 = splserial();
820 		COM_LOCK(sc);
821 
822 		if (sc->enable) {
823 			if ((*sc->enable)(sc)) {
824 				COM_UNLOCK(sc);
825 				splx(s2);
826 				splx(s);
827 				printf("%s: device enable failed\n",
828 				       sc->sc_dev.dv_xname);
829 				return (EIO);
830 			}
831 			sc->enabled = 1;
832 			com_config(sc);
833 		}
834 
835 		/* Turn on interrupts. */
836 		sc->sc_ier = IER_ERXRDY | IER_ERLS | IER_EMSC;
837 		bus_space_write_1(sc->sc_iot, sc->sc_ioh, com_ier, sc->sc_ier);
838 
839 		/* Fetch the current modem control status, needed later. */
840 		sc->sc_msr = bus_space_read_1(sc->sc_iot, sc->sc_ioh, com_msr);
841 
842 		/* Clear PPS capture state on first open. */
843 		sc->sc_ppsmask = 0;
844 		sc->ppsparam.mode = 0;
845 
846 		COM_UNLOCK(sc);
847 		splx(s2);
848 
849 		/*
850 		 * Initialize the termios status to the defaults.  Add in the
851 		 * sticky bits from TIOCSFLAGS.
852 		 */
853 		t.c_ispeed = 0;
854 		if (ISSET(sc->sc_hwflags, COM_HW_CONSOLE)) {
855 			t.c_ospeed = comconsrate;
856 			t.c_cflag = comconscflag;
857 		} else {
858 			t.c_ospeed = TTYDEF_SPEED;
859 			t.c_cflag = TTYDEF_CFLAG;
860 		}
861 		if (ISSET(sc->sc_swflags, TIOCFLAG_CLOCAL))
862 			SET(t.c_cflag, CLOCAL);
863 		if (ISSET(sc->sc_swflags, TIOCFLAG_CRTSCTS))
864 			SET(t.c_cflag, CRTSCTS);
865 		if (ISSET(sc->sc_swflags, TIOCFLAG_MDMBUF))
866 			SET(t.c_cflag, MDMBUF);
867 		/* Make sure comparam() will do something. */
868 		tp->t_ospeed = 0;
869 		(void) comparam(tp, &t);
870 		tp->t_iflag = TTYDEF_IFLAG;
871 		tp->t_oflag = TTYDEF_OFLAG;
872 		tp->t_lflag = TTYDEF_LFLAG;
873 		ttychars(tp);
874 		ttsetwater(tp);
875 
876 		s2 = splserial();
877 		COM_LOCK(sc);
878 
879 		/*
880 		 * Turn on DTR.  We must always do this, even if carrier is not
881 		 * present, because otherwise we'd have to use TIOCSDTR
882 		 * immediately after setting CLOCAL, which applications do not
883 		 * expect.  We always assert DTR while the device is open
884 		 * unless explicitly requested to deassert it.
885 		 */
886 		com_modem(sc, 1);
887 
888 		/* Clear the input ring, and unblock. */
889 		sc->sc_rbput = sc->sc_rbget = sc->sc_rbuf;
890 		sc->sc_rbavail = com_rbuf_size;
891 		com_iflush(sc);
892 		CLR(sc->sc_rx_flags, RX_ANY_BLOCK);
893 		com_hwiflow(sc);
894 
895 #ifdef COM_DEBUG
896 		if (com_debug)
897 			comstatus(sc, "comopen  ");
898 #endif
899 
900 		COM_UNLOCK(sc);
901 		splx(s2);
902 	}
903 
904 	splx(s);
905 
906 	error = ttyopen(tp, COMDIALOUT(dev), ISSET(flag, O_NONBLOCK));
907 	if (error)
908 		goto bad;
909 
910 	error = (*tp->t_linesw->l_open)(dev, tp);
911 	if (error)
912 		goto bad;
913 
914 	return (0);
915 
916 bad:
917 	if (!ISSET(tp->t_state, TS_ISOPEN) && tp->t_wopen == 0) {
918 		/*
919 		 * We failed to open the device, and nobody else had it opened.
920 		 * Clean up the state as appropriate.
921 		 */
922 		com_shutdown(sc);
923 	}
924 
925 	return (error);
926 }
927 
928 int
929 comclose(dev, flag, mode, p)
930 	dev_t dev;
931 	int flag, mode;
932 	struct proc *p;
933 {
934 	struct com_softc *sc = device_lookup(&com_cd, COMUNIT(dev));
935 	struct tty *tp = sc->sc_tty;
936 
937 	/* XXX This is for cons.c. */
938 	if (!ISSET(tp->t_state, TS_ISOPEN))
939 		return (0);
940 
941 	(*tp->t_linesw->l_close)(tp, flag);
942 	ttyclose(tp);
943 
944 	if (COM_ISALIVE(sc) == 0)
945 		return (0);
946 
947 	if (!ISSET(tp->t_state, TS_ISOPEN) && tp->t_wopen == 0) {
948 		/*
949 		 * Although we got a last close, the device may still be in
950 		 * use; e.g. if this was the dialout node, and there are still
951 		 * processes waiting for carrier on the non-dialout node.
952 		 */
953 		com_shutdown(sc);
954 	}
955 
956 	return (0);
957 }
958 
959 int
960 comread(dev, uio, flag)
961 	dev_t dev;
962 	struct uio *uio;
963 	int flag;
964 {
965 	struct com_softc *sc = device_lookup(&com_cd, COMUNIT(dev));
966 	struct tty *tp = sc->sc_tty;
967 
968 	if (COM_ISALIVE(sc) == 0)
969 		return (EIO);
970 
971 	return ((*tp->t_linesw->l_read)(tp, uio, flag));
972 }
973 
974 int
975 comwrite(dev, uio, flag)
976 	dev_t dev;
977 	struct uio *uio;
978 	int flag;
979 {
980 	struct com_softc *sc = device_lookup(&com_cd, COMUNIT(dev));
981 	struct tty *tp = sc->sc_tty;
982 
983 	if (COM_ISALIVE(sc) == 0)
984 		return (EIO);
985 
986 	return ((*tp->t_linesw->l_write)(tp, uio, flag));
987 }
988 
989 struct tty *
990 comtty(dev)
991 	dev_t dev;
992 {
993 	struct com_softc *sc = device_lookup(&com_cd, COMUNIT(dev));
994 	struct tty *tp = sc->sc_tty;
995 
996 	return (tp);
997 }
998 
999 int
1000 comioctl(dev, cmd, data, flag, p)
1001 	dev_t dev;
1002 	u_long cmd;
1003 	caddr_t data;
1004 	int flag;
1005 	struct proc *p;
1006 {
1007 	struct com_softc *sc = device_lookup(&com_cd, COMUNIT(dev));
1008 	struct tty *tp = sc->sc_tty;
1009 	int error;
1010 	int s;
1011 
1012 	if (COM_ISALIVE(sc) == 0)
1013 		return (EIO);
1014 
1015 	error = (*tp->t_linesw->l_ioctl)(tp, cmd, data, flag, p);
1016 	if (error >= 0)
1017 		return (error);
1018 
1019 	error = ttioctl(tp, cmd, data, flag, p);
1020 	if (error >= 0)
1021 		return (error);
1022 
1023 	error = 0;
1024 
1025 	s = splserial();
1026 	COM_LOCK(sc);
1027 
1028 	switch (cmd) {
1029 	case TIOCSBRK:
1030 		com_break(sc, 1);
1031 		break;
1032 
1033 	case TIOCCBRK:
1034 		com_break(sc, 0);
1035 		break;
1036 
1037 	case TIOCSDTR:
1038 		com_modem(sc, 1);
1039 		break;
1040 
1041 	case TIOCCDTR:
1042 		com_modem(sc, 0);
1043 		break;
1044 
1045 	case TIOCGFLAGS:
1046 		*(int *)data = sc->sc_swflags;
1047 		break;
1048 
1049 	case TIOCSFLAGS:
1050 		error = suser(p->p_ucred, &p->p_acflag);
1051 		if (error)
1052 			break;
1053 		sc->sc_swflags = *(int *)data;
1054 		break;
1055 
1056 	case TIOCMSET:
1057 	case TIOCMBIS:
1058 	case TIOCMBIC:
1059 		tiocm_to_com(sc, cmd, *(int *)data);
1060 		break;
1061 
1062 	case TIOCMGET:
1063 		*(int *)data = com_to_tiocm(sc);
1064 		break;
1065 
1066 	case PPS_IOC_CREATE:
1067 		break;
1068 
1069 	case PPS_IOC_DESTROY:
1070 		break;
1071 
1072 	case PPS_IOC_GETPARAMS: {
1073 		pps_params_t *pp;
1074 		pp = (pps_params_t *)data;
1075 		*pp = sc->ppsparam;
1076 		break;
1077 	}
1078 
1079 	case PPS_IOC_SETPARAMS: {
1080 	  	pps_params_t *pp;
1081 		int mode;
1082 		pp = (pps_params_t *)data;
1083 		if (pp->mode & ~ppscap) {
1084 			error = EINVAL;
1085 			break;
1086 		}
1087 		sc->ppsparam = *pp;
1088 	 	/*
1089 		 * Compute msr masks from user-specified timestamp state.
1090 		 */
1091 		mode = sc->ppsparam.mode;
1092 #ifdef	PPS_SYNC
1093 		if (mode & PPS_HARDPPSONASSERT) {
1094 			mode |= PPS_CAPTUREASSERT;
1095 			/* XXX revoke any previous HARDPPS source */
1096 		}
1097 		if (mode & PPS_HARDPPSONCLEAR) {
1098 			mode |= PPS_CAPTURECLEAR;
1099 			/* XXX revoke any previous HARDPPS source */
1100 		}
1101 #endif	/* PPS_SYNC */
1102 		switch (mode & PPS_CAPTUREBOTH) {
1103 		case 0:
1104 			sc->sc_ppsmask = 0;
1105 			break;
1106 
1107 		case PPS_CAPTUREASSERT:
1108 			sc->sc_ppsmask = MSR_DCD;
1109 			sc->sc_ppsassert = MSR_DCD;
1110 			sc->sc_ppsclear = -1;
1111 			break;
1112 
1113 		case PPS_CAPTURECLEAR:
1114 			sc->sc_ppsmask = MSR_DCD;
1115 			sc->sc_ppsassert = -1;
1116 			sc->sc_ppsclear = 0;
1117 			break;
1118 
1119 		case PPS_CAPTUREBOTH:
1120 			sc->sc_ppsmask = MSR_DCD;
1121 			sc->sc_ppsassert = MSR_DCD;
1122 			sc->sc_ppsclear = 0;
1123 			break;
1124 
1125 		default:
1126 			error = EINVAL;
1127 			break;
1128 		}
1129 		break;
1130 	}
1131 
1132 	case PPS_IOC_GETCAP:
1133 		*(int*)data = ppscap;
1134 		break;
1135 
1136 	case PPS_IOC_FETCH: {
1137 		pps_info_t *pi;
1138 		pi = (pps_info_t *)data;
1139 		*pi = sc->ppsinfo;
1140 		break;
1141 	}
1142 
1143 	case TIOCDCDTIMESTAMP:	/* XXX old, overloaded  API used by xntpd v3 */
1144 		/*
1145 		 * Some GPS clocks models use the falling rather than
1146 		 * rising edge as the on-the-second signal.
1147 		 * The old API has no way to specify PPS polarity.
1148 		 */
1149 		sc->sc_ppsmask = MSR_DCD;
1150 #ifndef PPS_TRAILING_EDGE
1151 		sc->sc_ppsassert = MSR_DCD;
1152 		sc->sc_ppsclear = -1;
1153 		TIMESPEC_TO_TIMEVAL((struct timeval *)data,
1154 		    &sc->ppsinfo.assert_timestamp);
1155 #else
1156 		sc->sc_ppsassert = -1
1157 		sc->sc_ppsclear = 0;
1158 		TIMESPEC_TO_TIMEVAL((struct timeval *)data,
1159 		    &sc->ppsinfo.clear_timestamp);
1160 #endif
1161 		break;
1162 
1163 	default:
1164 		error = ENOTTY;
1165 		break;
1166 	}
1167 
1168 	COM_UNLOCK(sc);
1169 	splx(s);
1170 
1171 #ifdef COM_DEBUG
1172 	if (com_debug)
1173 		comstatus(sc, "comioctl ");
1174 #endif
1175 
1176 	return (error);
1177 }
1178 
1179 integrate void
1180 com_schedrx(sc)
1181 	struct com_softc *sc;
1182 {
1183 
1184 	sc->sc_rx_ready = 1;
1185 
1186 	/* Wake up the poller. */
1187 #ifdef __HAVE_GENERIC_SOFT_INTERRUPTS
1188 	softintr_schedule(sc->sc_si);
1189 #else
1190 #ifndef __NO_SOFT_SERIAL_INTERRUPT
1191 	setsoftserial();
1192 #else
1193 	if (!com_softintr_scheduled) {
1194 		com_softintr_scheduled = 1;
1195 		callout_reset(&comsoft_callout, 1, comsoft, NULL);
1196 	}
1197 #endif
1198 #endif
1199 }
1200 
1201 void
1202 com_break(sc, onoff)
1203 	struct com_softc *sc;
1204 	int onoff;
1205 {
1206 
1207 	if (onoff)
1208 		SET(sc->sc_lcr, LCR_SBREAK);
1209 	else
1210 		CLR(sc->sc_lcr, LCR_SBREAK);
1211 
1212 	if (!sc->sc_heldchange) {
1213 		if (sc->sc_tx_busy) {
1214 			sc->sc_heldtbc = sc->sc_tbc;
1215 			sc->sc_tbc = 0;
1216 			sc->sc_heldchange = 1;
1217 		} else
1218 			com_loadchannelregs(sc);
1219 	}
1220 }
1221 
1222 void
1223 com_modem(sc, onoff)
1224 	struct com_softc *sc;
1225 	int onoff;
1226 {
1227 
1228 	if (sc->sc_mcr_dtr == 0)
1229 		return;
1230 
1231 	if (onoff)
1232 		SET(sc->sc_mcr, sc->sc_mcr_dtr);
1233 	else
1234 		CLR(sc->sc_mcr, sc->sc_mcr_dtr);
1235 
1236 	if (!sc->sc_heldchange) {
1237 		if (sc->sc_tx_busy) {
1238 			sc->sc_heldtbc = sc->sc_tbc;
1239 			sc->sc_tbc = 0;
1240 			sc->sc_heldchange = 1;
1241 		} else
1242 			com_loadchannelregs(sc);
1243 	}
1244 }
1245 
1246 void
1247 tiocm_to_com(sc, how, ttybits)
1248 	struct com_softc *sc;
1249 	u_long how;
1250 	int ttybits;
1251 {
1252 	u_char combits;
1253 
1254 	combits = 0;
1255 	if (ISSET(ttybits, TIOCM_DTR))
1256 		SET(combits, MCR_DTR);
1257 	if (ISSET(ttybits, TIOCM_RTS))
1258 		SET(combits, MCR_RTS);
1259 
1260 	switch (how) {
1261 	case TIOCMBIC:
1262 		CLR(sc->sc_mcr, combits);
1263 		break;
1264 
1265 	case TIOCMBIS:
1266 		SET(sc->sc_mcr, combits);
1267 		break;
1268 
1269 	case TIOCMSET:
1270 		CLR(sc->sc_mcr, MCR_DTR | MCR_RTS);
1271 		SET(sc->sc_mcr, combits);
1272 		break;
1273 	}
1274 
1275 	if (!sc->sc_heldchange) {
1276 		if (sc->sc_tx_busy) {
1277 			sc->sc_heldtbc = sc->sc_tbc;
1278 			sc->sc_tbc = 0;
1279 			sc->sc_heldchange = 1;
1280 		} else
1281 			com_loadchannelregs(sc);
1282 	}
1283 }
1284 
1285 int
1286 com_to_tiocm(sc)
1287 	struct com_softc *sc;
1288 {
1289 	u_char combits;
1290 	int ttybits = 0;
1291 
1292 	combits = sc->sc_mcr;
1293 	if (ISSET(combits, MCR_DTR))
1294 		SET(ttybits, TIOCM_DTR);
1295 	if (ISSET(combits, MCR_RTS))
1296 		SET(ttybits, TIOCM_RTS);
1297 
1298 	combits = sc->sc_msr;
1299 	if (ISSET(combits, MSR_DCD))
1300 		SET(ttybits, TIOCM_CD);
1301 	if (ISSET(combits, MSR_CTS))
1302 		SET(ttybits, TIOCM_CTS);
1303 	if (ISSET(combits, MSR_DSR))
1304 		SET(ttybits, TIOCM_DSR);
1305 	if (ISSET(combits, MSR_RI | MSR_TERI))
1306 		SET(ttybits, TIOCM_RI);
1307 
1308 	if (sc->sc_ier != 0)
1309 		SET(ttybits, TIOCM_LE);
1310 
1311 	return (ttybits);
1312 }
1313 
1314 static u_char
1315 cflag2lcr(cflag)
1316 	tcflag_t cflag;
1317 {
1318 	u_char lcr = 0;
1319 
1320 	switch (ISSET(cflag, CSIZE)) {
1321 	case CS5:
1322 		SET(lcr, LCR_5BITS);
1323 		break;
1324 	case CS6:
1325 		SET(lcr, LCR_6BITS);
1326 		break;
1327 	case CS7:
1328 		SET(lcr, LCR_7BITS);
1329 		break;
1330 	case CS8:
1331 		SET(lcr, LCR_8BITS);
1332 		break;
1333 	}
1334 	if (ISSET(cflag, PARENB)) {
1335 		SET(lcr, LCR_PENAB);
1336 		if (!ISSET(cflag, PARODD))
1337 			SET(lcr, LCR_PEVEN);
1338 	}
1339 	if (ISSET(cflag, CSTOPB))
1340 		SET(lcr, LCR_STOPB);
1341 
1342 	return (lcr);
1343 }
1344 
1345 int
1346 comparam(tp, t)
1347 	struct tty *tp;
1348 	struct termios *t;
1349 {
1350 	struct com_softc *sc = device_lookup(&com_cd, COMUNIT(tp->t_dev));
1351 	int ospeed = comspeed(t->c_ospeed, sc->sc_frequency);
1352 	u_char lcr;
1353 	int s;
1354 
1355 	if (COM_ISALIVE(sc) == 0)
1356 		return (EIO);
1357 
1358 	/* Check requested parameters. */
1359 	if (ospeed < 0)
1360 		return (EINVAL);
1361 	if (t->c_ispeed && t->c_ispeed != t->c_ospeed)
1362 		return (EINVAL);
1363 
1364 	/*
1365 	 * For the console, always force CLOCAL and !HUPCL, so that the port
1366 	 * is always active.
1367 	 */
1368 	if (ISSET(sc->sc_swflags, TIOCFLAG_SOFTCAR) ||
1369 	    ISSET(sc->sc_hwflags, COM_HW_CONSOLE)) {
1370 		SET(t->c_cflag, CLOCAL);
1371 		CLR(t->c_cflag, HUPCL);
1372 	}
1373 
1374 	/*
1375 	 * If there were no changes, don't do anything.  This avoids dropping
1376 	 * input and improves performance when all we did was frob things like
1377 	 * VMIN and VTIME.
1378 	 */
1379 	if (tp->t_ospeed == t->c_ospeed &&
1380 	    tp->t_cflag == t->c_cflag)
1381 		return (0);
1382 
1383 	lcr = ISSET(sc->sc_lcr, LCR_SBREAK) | cflag2lcr(t->c_cflag);
1384 
1385 	s = splserial();
1386 	COM_LOCK(sc);
1387 
1388 	sc->sc_lcr = lcr;
1389 
1390 	/*
1391 	 * If we're not in a mode that assumes a connection is present, then
1392 	 * ignore carrier changes.
1393 	 */
1394 	if (ISSET(t->c_cflag, CLOCAL | MDMBUF))
1395 		sc->sc_msr_dcd = 0;
1396 	else
1397 		sc->sc_msr_dcd = MSR_DCD;
1398 	/*
1399 	 * Set the flow control pins depending on the current flow control
1400 	 * mode.
1401 	 */
1402 	if (ISSET(t->c_cflag, CRTSCTS)) {
1403 		sc->sc_mcr_dtr = MCR_DTR;
1404 		sc->sc_mcr_rts = MCR_RTS;
1405 		sc->sc_msr_cts = MSR_CTS;
1406 		sc->sc_efr = EFR_AUTORTS | EFR_AUTOCTS;
1407 	} else if (ISSET(t->c_cflag, MDMBUF)) {
1408 		/*
1409 		 * For DTR/DCD flow control, make sure we don't toggle DTR for
1410 		 * carrier detection.
1411 		 */
1412 		sc->sc_mcr_dtr = 0;
1413 		sc->sc_mcr_rts = MCR_DTR;
1414 		sc->sc_msr_cts = MSR_DCD;
1415 		sc->sc_efr = 0;
1416 	} else {
1417 		/*
1418 		 * If no flow control, then always set RTS.  This will make
1419 		 * the other side happy if it mistakenly thinks we're doing
1420 		 * RTS/CTS flow control.
1421 		 */
1422 		sc->sc_mcr_dtr = MCR_DTR | MCR_RTS;
1423 		sc->sc_mcr_rts = 0;
1424 		sc->sc_msr_cts = 0;
1425 		sc->sc_efr = 0;
1426 		if (ISSET(sc->sc_mcr, MCR_DTR))
1427 			SET(sc->sc_mcr, MCR_RTS);
1428 		else
1429 			CLR(sc->sc_mcr, MCR_RTS);
1430 	}
1431 	sc->sc_msr_mask = sc->sc_msr_cts | sc->sc_msr_dcd;
1432 
1433 #if 0
1434 	if (ospeed == 0)
1435 		CLR(sc->sc_mcr, sc->sc_mcr_dtr);
1436 	else
1437 		SET(sc->sc_mcr, sc->sc_mcr_dtr);
1438 #endif
1439 
1440 	sc->sc_dlbl = ospeed;
1441 	sc->sc_dlbh = ospeed >> 8;
1442 
1443 	/*
1444 	 * Set the FIFO threshold based on the receive speed.
1445 	 *
1446 	 *  * If it's a low speed, it's probably a mouse or some other
1447 	 *    interactive device, so set the threshold low.
1448 	 *  * If it's a high speed, trim the trigger level down to prevent
1449 	 *    overflows.
1450 	 *  * Otherwise set it a bit higher.
1451 	 */
1452 	if (ISSET(sc->sc_hwflags, COM_HW_HAYESP))
1453 		sc->sc_fifo = FIFO_DMA_MODE | FIFO_ENABLE | FIFO_TRIGGER_8;
1454 	else if (ISSET(sc->sc_hwflags, COM_HW_FIFO))
1455 		sc->sc_fifo = FIFO_ENABLE |
1456 		    (t->c_ospeed <= 1200 ? FIFO_TRIGGER_1 :
1457 		     t->c_ospeed <= 38400 ? FIFO_TRIGGER_8 : FIFO_TRIGGER_4);
1458 	else
1459 		sc->sc_fifo = 0;
1460 
1461 	/* And copy to tty. */
1462 	tp->t_ispeed = 0;
1463 	tp->t_ospeed = t->c_ospeed;
1464 	tp->t_cflag = t->c_cflag;
1465 
1466 	if (!sc->sc_heldchange) {
1467 		if (sc->sc_tx_busy) {
1468 			sc->sc_heldtbc = sc->sc_tbc;
1469 			sc->sc_tbc = 0;
1470 			sc->sc_heldchange = 1;
1471 		} else
1472 			com_loadchannelregs(sc);
1473 	}
1474 
1475 	if (!ISSET(t->c_cflag, CHWFLOW)) {
1476 		/* Disable the high water mark. */
1477 		sc->sc_r_hiwat = 0;
1478 		sc->sc_r_lowat = 0;
1479 		if (ISSET(sc->sc_rx_flags, RX_TTY_OVERFLOWED)) {
1480 			CLR(sc->sc_rx_flags, RX_TTY_OVERFLOWED);
1481 			com_schedrx(sc);
1482 		}
1483 		if (ISSET(sc->sc_rx_flags, RX_TTY_BLOCKED|RX_IBUF_BLOCKED)) {
1484 			CLR(sc->sc_rx_flags, RX_TTY_BLOCKED|RX_IBUF_BLOCKED);
1485 			com_hwiflow(sc);
1486 		}
1487 	} else {
1488 		sc->sc_r_hiwat = com_rbuf_hiwat;
1489 		sc->sc_r_lowat = com_rbuf_lowat;
1490 	}
1491 
1492 	COM_UNLOCK(sc);
1493 	splx(s);
1494 
1495 	/*
1496 	 * Update the tty layer's idea of the carrier bit, in case we changed
1497 	 * CLOCAL or MDMBUF.  We don't hang up here; we only do that by
1498 	 * explicit request.
1499 	 */
1500 	(void) (*tp->t_linesw->l_modem)(tp, ISSET(sc->sc_msr, MSR_DCD));
1501 
1502 #ifdef COM_DEBUG
1503 	if (com_debug)
1504 		comstatus(sc, "comparam ");
1505 #endif
1506 
1507 	if (!ISSET(t->c_cflag, CHWFLOW)) {
1508 		if (sc->sc_tx_stopped) {
1509 			sc->sc_tx_stopped = 0;
1510 			comstart(tp);
1511 		}
1512 	}
1513 
1514 	return (0);
1515 }
1516 
1517 void
1518 com_iflush(sc)
1519 	struct com_softc *sc;
1520 {
1521 	bus_space_tag_t iot = sc->sc_iot;
1522 	bus_space_handle_t ioh = sc->sc_ioh;
1523 #ifdef DIAGNOSTIC
1524 	int reg;
1525 #endif
1526 	int timo;
1527 
1528 #ifdef DIAGNOSTIC
1529 	reg = 0xffff;
1530 #endif
1531 	timo = 50000;
1532 	/* flush any pending I/O */
1533 	while (ISSET(bus_space_read_1(iot, ioh, com_lsr), LSR_RXRDY)
1534 	    && --timo)
1535 #ifdef DIAGNOSTIC
1536 		reg =
1537 #else
1538 		    (void)
1539 #endif
1540 		    bus_space_read_1(iot, ioh, com_data);
1541 #ifdef DIAGNOSTIC
1542 	if (!timo)
1543 		printf("%s: com_iflush timeout %02x\n", sc->sc_dev.dv_xname,
1544 		       reg);
1545 #endif
1546 }
1547 
1548 void
1549 com_loadchannelregs(sc)
1550 	struct com_softc *sc;
1551 {
1552 	bus_space_tag_t iot = sc->sc_iot;
1553 	bus_space_handle_t ioh = sc->sc_ioh;
1554 
1555 	/* XXXXX necessary? */
1556 	com_iflush(sc);
1557 
1558 	bus_space_write_1(iot, ioh, com_ier, 0);
1559 
1560 	if (ISSET(sc->sc_hwflags, COM_HW_FLOW)) {
1561 		bus_space_write_1(iot, ioh, com_lcr, LCR_EERS);
1562 		bus_space_write_1(iot, ioh, com_efr, sc->sc_efr);
1563 	}
1564 	bus_space_write_1(iot, ioh, com_lcr, sc->sc_lcr | LCR_DLAB);
1565 	bus_space_write_1(iot, ioh, com_dlbl, sc->sc_dlbl);
1566 	bus_space_write_1(iot, ioh, com_dlbh, sc->sc_dlbh);
1567 	bus_space_write_1(iot, ioh, com_lcr, sc->sc_lcr);
1568 	bus_space_write_1(iot, ioh, com_mcr, sc->sc_mcr_active = sc->sc_mcr);
1569 	bus_space_write_1(iot, ioh, com_fifo, sc->sc_fifo);
1570 
1571 	bus_space_write_1(iot, ioh, com_ier, sc->sc_ier);
1572 }
1573 
1574 int
1575 comhwiflow(tp, block)
1576 	struct tty *tp;
1577 	int block;
1578 {
1579 	struct com_softc *sc = device_lookup(&com_cd, COMUNIT(tp->t_dev));
1580 	int s;
1581 
1582 	if (COM_ISALIVE(sc) == 0)
1583 		return (0);
1584 
1585 	if (sc->sc_mcr_rts == 0)
1586 		return (0);
1587 
1588 	s = splserial();
1589 	COM_LOCK(sc);
1590 
1591 	if (block) {
1592 		if (!ISSET(sc->sc_rx_flags, RX_TTY_BLOCKED)) {
1593 			SET(sc->sc_rx_flags, RX_TTY_BLOCKED);
1594 			com_hwiflow(sc);
1595 		}
1596 	} else {
1597 		if (ISSET(sc->sc_rx_flags, RX_TTY_OVERFLOWED)) {
1598 			CLR(sc->sc_rx_flags, RX_TTY_OVERFLOWED);
1599 			com_schedrx(sc);
1600 		}
1601 		if (ISSET(sc->sc_rx_flags, RX_TTY_BLOCKED)) {
1602 			CLR(sc->sc_rx_flags, RX_TTY_BLOCKED);
1603 			com_hwiflow(sc);
1604 		}
1605 	}
1606 
1607 	COM_UNLOCK(sc);
1608 	splx(s);
1609 	return (1);
1610 }
1611 
1612 /*
1613  * (un)block input via hw flowcontrol
1614  */
1615 void
1616 com_hwiflow(sc)
1617 	struct com_softc *sc;
1618 {
1619 	bus_space_tag_t iot = sc->sc_iot;
1620 	bus_space_handle_t ioh = sc->sc_ioh;
1621 
1622 	if (sc->sc_mcr_rts == 0)
1623 		return;
1624 
1625 	if (ISSET(sc->sc_rx_flags, RX_ANY_BLOCK)) {
1626 		CLR(sc->sc_mcr, sc->sc_mcr_rts);
1627 		CLR(sc->sc_mcr_active, sc->sc_mcr_rts);
1628 	} else {
1629 		SET(sc->sc_mcr, sc->sc_mcr_rts);
1630 		SET(sc->sc_mcr_active, sc->sc_mcr_rts);
1631 	}
1632 	bus_space_write_1(iot, ioh, com_mcr, sc->sc_mcr_active);
1633 }
1634 
1635 
1636 void
1637 comstart(tp)
1638 	struct tty *tp;
1639 {
1640 	struct com_softc *sc = device_lookup(&com_cd, COMUNIT(tp->t_dev));
1641 	bus_space_tag_t iot = sc->sc_iot;
1642 	bus_space_handle_t ioh = sc->sc_ioh;
1643 	int s;
1644 
1645 	if (COM_ISALIVE(sc) == 0)
1646 		return;
1647 
1648 	s = spltty();
1649 	if (ISSET(tp->t_state, TS_BUSY | TS_TIMEOUT | TS_TTSTOP))
1650 		goto out;
1651 	if (sc->sc_tx_stopped)
1652 		goto out;
1653 
1654 	if (tp->t_outq.c_cc <= tp->t_lowat) {
1655 		if (ISSET(tp->t_state, TS_ASLEEP)) {
1656 			CLR(tp->t_state, TS_ASLEEP);
1657 			wakeup(&tp->t_outq);
1658 		}
1659 		selwakeup(&tp->t_wsel);
1660 		if (tp->t_outq.c_cc == 0)
1661 			goto out;
1662 	}
1663 
1664 	/* Grab the first contiguous region of buffer space. */
1665 	{
1666 		u_char *tba;
1667 		int tbc;
1668 
1669 		tba = tp->t_outq.c_cf;
1670 		tbc = ndqb(&tp->t_outq, 0);
1671 
1672 		(void)splserial();
1673 		COM_LOCK(sc);
1674 
1675 		sc->sc_tba = tba;
1676 		sc->sc_tbc = tbc;
1677 	}
1678 
1679 	SET(tp->t_state, TS_BUSY);
1680 	sc->sc_tx_busy = 1;
1681 
1682 	/* Enable transmit completion interrupts if necessary. */
1683 	if (!ISSET(sc->sc_ier, IER_ETXRDY)) {
1684 		SET(sc->sc_ier, IER_ETXRDY);
1685 		bus_space_write_1(iot, ioh, com_ier, sc->sc_ier);
1686 	}
1687 
1688 	/* Output the first chunk of the contiguous buffer. */
1689 	{
1690 		int n;
1691 
1692 		n = sc->sc_tbc;
1693 		if (n > sc->sc_fifolen)
1694 			n = sc->sc_fifolen;
1695 		bus_space_write_multi_1(iot, ioh, com_data, sc->sc_tba, n);
1696 		sc->sc_tbc -= n;
1697 		sc->sc_tba += n;
1698 	}
1699 	COM_UNLOCK(sc);
1700 out:
1701 	splx(s);
1702 	return;
1703 }
1704 
1705 /*
1706  * Stop output on a line.
1707  */
1708 void
1709 comstop(tp, flag)
1710 	struct tty *tp;
1711 	int flag;
1712 {
1713 	struct com_softc *sc = device_lookup(&com_cd, COMUNIT(tp->t_dev));
1714 	int s;
1715 
1716 	s = splserial();
1717 	COM_LOCK(sc);
1718 	if (ISSET(tp->t_state, TS_BUSY)) {
1719 		/* Stop transmitting at the next chunk. */
1720 		sc->sc_tbc = 0;
1721 		sc->sc_heldtbc = 0;
1722 		if (!ISSET(tp->t_state, TS_TTSTOP))
1723 			SET(tp->t_state, TS_FLUSH);
1724 	}
1725 	COM_UNLOCK(sc);
1726 	splx(s);
1727 }
1728 
1729 void
1730 comdiag(arg)
1731 	void *arg;
1732 {
1733 	struct com_softc *sc = arg;
1734 	int overflows, floods;
1735 	int s;
1736 
1737 	s = splserial();
1738 	COM_LOCK(sc);
1739 	overflows = sc->sc_overflows;
1740 	sc->sc_overflows = 0;
1741 	floods = sc->sc_floods;
1742 	sc->sc_floods = 0;
1743 	sc->sc_errors = 0;
1744 	COM_UNLOCK(sc);
1745 	splx(s);
1746 
1747 	log(LOG_WARNING, "%s: %d silo overflow%s, %d ibuf flood%s\n",
1748 	    sc->sc_dev.dv_xname,
1749 	    overflows, overflows == 1 ? "" : "s",
1750 	    floods, floods == 1 ? "" : "s");
1751 }
1752 
1753 integrate void
1754 com_rxsoft(sc, tp)
1755 	struct com_softc *sc;
1756 	struct tty *tp;
1757 {
1758 	int (*rint) __P((int c, struct tty *tp)) = tp->t_linesw->l_rint;
1759 	u_char *get, *end;
1760 	u_int cc, scc;
1761 	u_char lsr;
1762 	int code;
1763 	int s;
1764 
1765 	end = sc->sc_ebuf;
1766 	get = sc->sc_rbget;
1767 	scc = cc = com_rbuf_size - sc->sc_rbavail;
1768 
1769 	if (cc == com_rbuf_size) {
1770 		sc->sc_floods++;
1771 		if (sc->sc_errors++ == 0)
1772 			callout_reset(&sc->sc_diag_callout, 60 * hz,
1773 			    comdiag, sc);
1774 	}
1775 
1776 	while (cc) {
1777 		code = get[0];
1778 		lsr = get[1];
1779 		if (ISSET(lsr, LSR_OE | LSR_BI | LSR_FE | LSR_PE)) {
1780 			if (ISSET(lsr, LSR_OE)) {
1781 				sc->sc_overflows++;
1782 				if (sc->sc_errors++ == 0)
1783 					callout_reset(&sc->sc_diag_callout,
1784 					    60 * hz, comdiag, sc);
1785 			}
1786 			if (ISSET(lsr, LSR_BI | LSR_FE))
1787 				SET(code, TTY_FE);
1788 			if (ISSET(lsr, LSR_PE))
1789 				SET(code, TTY_PE);
1790 		}
1791 		if ((*rint)(code, tp) == -1) {
1792 			/*
1793 			 * The line discipline's buffer is out of space.
1794 			 */
1795 			if (!ISSET(sc->sc_rx_flags, RX_TTY_BLOCKED)) {
1796 				/*
1797 				 * We're either not using flow control, or the
1798 				 * line discipline didn't tell us to block for
1799 				 * some reason.  Either way, we have no way to
1800 				 * know when there's more space available, so
1801 				 * just drop the rest of the data.
1802 				 */
1803 				get += cc << 1;
1804 				if (get >= end)
1805 					get -= com_rbuf_size << 1;
1806 				cc = 0;
1807 			} else {
1808 				/*
1809 				 * Don't schedule any more receive processing
1810 				 * until the line discipline tells us there's
1811 				 * space available (through comhwiflow()).
1812 				 * Leave the rest of the data in the input
1813 				 * buffer.
1814 				 */
1815 				SET(sc->sc_rx_flags, RX_TTY_OVERFLOWED);
1816 			}
1817 			break;
1818 		}
1819 		get += 2;
1820 		if (get >= end)
1821 			get = sc->sc_rbuf;
1822 		cc--;
1823 	}
1824 
1825 	if (cc != scc) {
1826 		sc->sc_rbget = get;
1827 		s = splserial();
1828 		COM_LOCK(sc);
1829 
1830 		cc = sc->sc_rbavail += scc - cc;
1831 		/* Buffers should be ok again, release possible block. */
1832 		if (cc >= sc->sc_r_lowat) {
1833 			if (ISSET(sc->sc_rx_flags, RX_IBUF_OVERFLOWED)) {
1834 				CLR(sc->sc_rx_flags, RX_IBUF_OVERFLOWED);
1835 				SET(sc->sc_ier, IER_ERXRDY);
1836 				bus_space_write_1(sc->sc_iot, sc->sc_ioh, com_ier, sc->sc_ier);
1837 			}
1838 			if (ISSET(sc->sc_rx_flags, RX_IBUF_BLOCKED)) {
1839 				CLR(sc->sc_rx_flags, RX_IBUF_BLOCKED);
1840 				com_hwiflow(sc);
1841 			}
1842 		}
1843 		COM_UNLOCK(sc);
1844 		splx(s);
1845 	}
1846 }
1847 
1848 integrate void
1849 com_txsoft(sc, tp)
1850 	struct com_softc *sc;
1851 	struct tty *tp;
1852 {
1853 
1854 	CLR(tp->t_state, TS_BUSY);
1855 	if (ISSET(tp->t_state, TS_FLUSH))
1856 		CLR(tp->t_state, TS_FLUSH);
1857 	else
1858 		ndflush(&tp->t_outq, (int)(sc->sc_tba - tp->t_outq.c_cf));
1859 	(*tp->t_linesw->l_start)(tp);
1860 }
1861 
1862 integrate void
1863 com_stsoft(sc, tp)
1864 	struct com_softc *sc;
1865 	struct tty *tp;
1866 {
1867 	u_char msr, delta;
1868 	int s;
1869 
1870 	s = splserial();
1871 	COM_LOCK(sc);
1872 	msr = sc->sc_msr;
1873 	delta = sc->sc_msr_delta;
1874 	sc->sc_msr_delta = 0;
1875 	COM_UNLOCK(sc);
1876 	splx(s);
1877 
1878 	if (ISSET(delta, sc->sc_msr_dcd)) {
1879 		/*
1880 		 * Inform the tty layer that carrier detect changed.
1881 		 */
1882 		(void) (*tp->t_linesw->l_modem)(tp, ISSET(msr, MSR_DCD));
1883 	}
1884 
1885 	if (ISSET(delta, sc->sc_msr_cts)) {
1886 		/* Block or unblock output according to flow control. */
1887 		if (ISSET(msr, sc->sc_msr_cts)) {
1888 			sc->sc_tx_stopped = 0;
1889 			(*tp->t_linesw->l_start)(tp);
1890 		} else {
1891 			sc->sc_tx_stopped = 1;
1892 		}
1893 	}
1894 
1895 #ifdef COM_DEBUG
1896 	if (com_debug)
1897 		comstatus(sc, "com_stsoft");
1898 #endif
1899 }
1900 
1901 #ifdef __HAVE_GENERIC_SOFT_INTERRUPTS
1902 void
1903 comsoft(arg)
1904 	void *arg;
1905 {
1906 	struct com_softc *sc = arg;
1907 	struct tty *tp;
1908 
1909 	if (COM_ISALIVE(sc) == 0)
1910 		return;
1911 
1912 	{
1913 #else
1914 void
1915 #ifndef __NO_SOFT_SERIAL_INTERRUPT
1916 comsoft()
1917 #else
1918 comsoft(arg)
1919 	void *arg;
1920 #endif
1921 {
1922 	struct com_softc	*sc;
1923 	struct tty	*tp;
1924 	int	unit;
1925 #ifdef __NO_SOFT_SERIAL_INTERRUPT
1926 	int s;
1927 
1928 	s = splsoftserial();
1929 	com_softintr_scheduled = 0;
1930 #endif
1931 
1932 	for (unit = 0; unit < com_cd.cd_ndevs; unit++) {
1933 		sc = device_lookup(&com_cd, unit);
1934 		if (sc == NULL || !ISSET(sc->sc_hwflags, COM_HW_DEV_OK))
1935 			continue;
1936 
1937 		if (COM_ISALIVE(sc) == 0)
1938 			continue;
1939 
1940 		tp = sc->sc_tty;
1941 		if (tp == NULL)
1942 			continue;
1943 		if (!ISSET(tp->t_state, TS_ISOPEN) && tp->t_wopen == 0)
1944 			continue;
1945 #endif
1946 		tp = sc->sc_tty;
1947 
1948 		if (sc->sc_rx_ready) {
1949 			sc->sc_rx_ready = 0;
1950 			com_rxsoft(sc, tp);
1951 		}
1952 
1953 		if (sc->sc_st_check) {
1954 			sc->sc_st_check = 0;
1955 			com_stsoft(sc, tp);
1956 		}
1957 
1958 		if (sc->sc_tx_done) {
1959 			sc->sc_tx_done = 0;
1960 			com_txsoft(sc, tp);
1961 		}
1962 	}
1963 
1964 #ifndef __HAVE_GENERIC_SOFT_INTERRUPTS
1965 #ifdef __NO_SOFT_SERIAL_INTERRUPT
1966 	splx(s);
1967 #endif
1968 #endif
1969 }
1970 
1971 #ifdef __ALIGN_BRACKET_LEVEL_FOR_CTAGS
1972 	/* there has got to be a better way to do comsoft() */
1973 }}
1974 #endif
1975 
1976 int
1977 comintr(arg)
1978 	void *arg;
1979 {
1980 	struct com_softc *sc = arg;
1981 	bus_space_tag_t iot = sc->sc_iot;
1982 	bus_space_handle_t ioh = sc->sc_ioh;
1983 	u_char *put, *end;
1984 	u_int cc;
1985 	u_char lsr, iir;
1986 
1987 	if (COM_ISALIVE(sc) == 0)
1988 		return (0);
1989 
1990 	COM_LOCK(sc);
1991 	iir = bus_space_read_1(iot, ioh, com_iir);
1992 	if (ISSET(iir, IIR_NOPEND)) {
1993 		COM_UNLOCK(sc);
1994 		return (0);
1995 	}
1996 
1997 	end = sc->sc_ebuf;
1998 	put = sc->sc_rbput;
1999 	cc = sc->sc_rbavail;
2000 
2001 	do {
2002 		u_char	msr, delta;
2003 
2004 		lsr = bus_space_read_1(iot, ioh, com_lsr);
2005 #if defined(DDB) || defined(KGDB)
2006 		if (ISSET(lsr, LSR_BI)) {
2007 #ifndef DDB_BREAK_CHAR
2008 #ifdef DDB
2009 			if (ISSET(sc->sc_hwflags, COM_HW_CONSOLE)) {
2010 				console_debugger();
2011 				continue;
2012 			}
2013 #endif
2014 #ifdef KGDB
2015 			if (ISSET(sc->sc_hwflags, COM_HW_KGDB)) {
2016 				kgdb_connect(1);
2017 				continue;
2018 			}
2019 #endif
2020 #endif
2021 		}
2022 #endif /* DDB || KGDB */
2023 
2024 		if (ISSET(lsr, LSR_RCV_MASK) &&
2025 		    !ISSET(sc->sc_rx_flags, RX_IBUF_OVERFLOWED)) {
2026 			while (cc > 0) {
2027 				put[0] = bus_space_read_1(iot, ioh, com_data);
2028 				put[1] = lsr;
2029 #if defined(DDB) && defined(DDB_BREAK_CHAR)
2030 				if (put[0] == DDB_BREAK_CHAR &&
2031 				    ISSET(sc->sc_hwflags, COM_HW_CONSOLE)) {
2032 					console_debugger();
2033 
2034 					lsr = bus_space_read_1(iot, ioh, com_lsr);
2035 					if (!ISSET(lsr, LSR_RCV_MASK))
2036 						break;
2037 
2038 					continue;
2039 				}
2040 #endif
2041 				put += 2;
2042 				if (put >= end)
2043 					put = sc->sc_rbuf;
2044 				cc--;
2045 
2046 				lsr = bus_space_read_1(iot, ioh, com_lsr);
2047 				if (!ISSET(lsr, LSR_RCV_MASK))
2048 					break;
2049 			}
2050 
2051 			/*
2052 			 * Current string of incoming characters ended because
2053 			 * no more data was available or we ran out of space.
2054 			 * Schedule a receive event if any data was received.
2055 			 * If we're out of space, turn off receive interrupts.
2056 			 */
2057 			sc->sc_rbput = put;
2058 			sc->sc_rbavail = cc;
2059 			if (!ISSET(sc->sc_rx_flags, RX_TTY_OVERFLOWED))
2060 				sc->sc_rx_ready = 1;
2061 
2062 			/*
2063 			 * See if we are in danger of overflowing a buffer. If
2064 			 * so, use hardware flow control to ease the pressure.
2065 			 */
2066 			if (!ISSET(sc->sc_rx_flags, RX_IBUF_BLOCKED) &&
2067 			    cc < sc->sc_r_hiwat) {
2068 				SET(sc->sc_rx_flags, RX_IBUF_BLOCKED);
2069 				com_hwiflow(sc);
2070 			}
2071 
2072 			/*
2073 			 * If we're out of space, disable receive interrupts
2074 			 * until the queue has drained a bit.
2075 			 */
2076 			if (!cc) {
2077 				SET(sc->sc_rx_flags, RX_IBUF_OVERFLOWED);
2078 				CLR(sc->sc_ier, IER_ERXRDY);
2079 				bus_space_write_1(iot, ioh, com_ier, sc->sc_ier);
2080 			}
2081 		} else {
2082 			if ((iir & IIR_IMASK) == IIR_RXRDY) {
2083 				bus_space_write_1(iot, ioh, com_ier, 0);
2084 				delay(10);
2085 				bus_space_write_1(iot, ioh, com_ier,sc->sc_ier);
2086 				iir = IIR_NOPEND;
2087 				continue;
2088 			}
2089 		}
2090 
2091 		msr = bus_space_read_1(iot, ioh, com_msr);
2092 		delta = msr ^ sc->sc_msr;
2093 		sc->sc_msr = msr;
2094 		/*
2095 		 * Pulse-per-second (PSS) signals on edge of DCD?
2096 		 * Process these even if line discipline is ignoring DCD.
2097 		 */
2098 		if (delta & sc->sc_ppsmask) {
2099 			struct timeval tv;
2100 		    	if ((msr & sc->sc_ppsmask) == sc->sc_ppsassert) {
2101 				/* XXX nanotime() */
2102 				microtime(&tv);
2103 				TIMEVAL_TO_TIMESPEC(&tv,
2104 				    &sc->ppsinfo.assert_timestamp);
2105 				if (sc->ppsparam.mode & PPS_OFFSETASSERT) {
2106 					timespecadd(&sc->ppsinfo.assert_timestamp,
2107 					    &sc->ppsparam.assert_offset,
2108 						    &sc->ppsinfo.assert_timestamp);
2109 				}
2110 
2111 #ifdef PPS_SYNC
2112 				if (sc->ppsparam.mode & PPS_HARDPPSONASSERT)
2113 					hardpps(&tv, tv.tv_usec);
2114 #endif
2115 				sc->ppsinfo.assert_sequence++;
2116 				sc->ppsinfo.current_mode = sc->ppsparam.mode;
2117 
2118 			} else if ((msr & sc->sc_ppsmask) == sc->sc_ppsclear) {
2119 				/* XXX nanotime() */
2120 				microtime(&tv);
2121 				TIMEVAL_TO_TIMESPEC(&tv,
2122 				    &sc->ppsinfo.clear_timestamp);
2123 				if (sc->ppsparam.mode & PPS_OFFSETCLEAR) {
2124 					timespecadd(&sc->ppsinfo.clear_timestamp,
2125 					    &sc->ppsparam.clear_offset,
2126 					    &sc->ppsinfo.clear_timestamp);
2127 				}
2128 
2129 #ifdef PPS_SYNC
2130 				if (sc->ppsparam.mode & PPS_HARDPPSONCLEAR)
2131 					hardpps(&tv, tv.tv_usec);
2132 #endif
2133 				sc->ppsinfo.clear_sequence++;
2134 				sc->ppsinfo.current_mode = sc->ppsparam.mode;
2135 			}
2136 		}
2137 
2138 		/*
2139 		 * Process normal status changes
2140 		 */
2141 		if (ISSET(delta, sc->sc_msr_mask)) {
2142 			SET(sc->sc_msr_delta, delta);
2143 
2144 			/*
2145 			 * Stop output immediately if we lose the output
2146 			 * flow control signal or carrier detect.
2147 			 */
2148 			if (ISSET(~msr, sc->sc_msr_mask)) {
2149 				sc->sc_tbc = 0;
2150 				sc->sc_heldtbc = 0;
2151 #ifdef COM_DEBUG
2152 				if (com_debug)
2153 					comstatus(sc, "comintr  ");
2154 #endif
2155 			}
2156 
2157 			sc->sc_st_check = 1;
2158 		}
2159 	} while (!ISSET((iir = bus_space_read_1(iot, ioh, com_iir)), IIR_NOPEND));
2160 
2161 	/*
2162 	 * Done handling any receive interrupts. See if data can be
2163 	 * transmitted as well. Schedule tx done event if no data left
2164 	 * and tty was marked busy.
2165 	 */
2166 	if (ISSET(lsr, LSR_TXRDY)) {
2167 		/*
2168 		 * If we've delayed a parameter change, do it now, and restart
2169 		 * output.
2170 		 */
2171 		if (sc->sc_heldchange) {
2172 			com_loadchannelregs(sc);
2173 			sc->sc_heldchange = 0;
2174 			sc->sc_tbc = sc->sc_heldtbc;
2175 			sc->sc_heldtbc = 0;
2176 		}
2177 
2178 		/* Output the next chunk of the contiguous buffer, if any. */
2179 		if (sc->sc_tbc > 0) {
2180 			int n;
2181 
2182 			n = sc->sc_tbc;
2183 			if (n > sc->sc_fifolen)
2184 				n = sc->sc_fifolen;
2185 			bus_space_write_multi_1(iot, ioh, com_data, sc->sc_tba, n);
2186 			sc->sc_tbc -= n;
2187 			sc->sc_tba += n;
2188 		} else {
2189 			/* Disable transmit completion interrupts if necessary. */
2190 			if (ISSET(sc->sc_ier, IER_ETXRDY)) {
2191 				CLR(sc->sc_ier, IER_ETXRDY);
2192 				bus_space_write_1(iot, ioh, com_ier, sc->sc_ier);
2193 			}
2194 			if (sc->sc_tx_busy) {
2195 				sc->sc_tx_busy = 0;
2196 				sc->sc_tx_done = 1;
2197 			}
2198 		}
2199 	}
2200 	COM_UNLOCK(sc);
2201 
2202 	/* Wake up the poller. */
2203 #ifdef __HAVE_GENERIC_SOFT_INTERRUPTS
2204 	softintr_schedule(sc->sc_si);
2205 #else
2206 #ifndef __NO_SOFT_SERIAL_INTERRUPT
2207 	setsoftserial();
2208 #else
2209 	if (!com_softintr_scheduled) {
2210 		com_softintr_scheduled = 1;
2211 		callout_reset(&comsoft_callout, 1, comsoft, NULL);
2212 	}
2213 #endif
2214 #endif
2215 
2216 #if NRND > 0 && defined(RND_COM)
2217 	rnd_add_uint32(&sc->rnd_source, iir | lsr);
2218 #endif
2219 
2220 	return (1);
2221 }
2222 
2223 /*
2224  * The following functions are polled getc and putc routines, shared
2225  * by the console and kgdb glue.
2226  */
2227 
2228 #if defined(DDB) && defined(DDB_BREAK_CHAR)
2229 #define MAX_UNGETC	20
2230 static int com_ungetc[MAX_UNGETC];
2231 static int com_ungetccount = 0;
2232 #endif
2233 
2234 int
2235 com_common_getc(iot, ioh)
2236 	bus_space_tag_t iot;
2237 	bus_space_handle_t ioh;
2238 {
2239 	int s = splserial();
2240 	u_char stat, c;
2241 
2242 #if defined(DDB) && defined(DDB_BREAK_CHAR)
2243 	/* got a character from reading things earlier */
2244 	if (com_ungetccount > 0) {
2245 		int i;
2246 
2247 		c = com_ungetc[0];
2248 		for (i = 1; i < com_ungetccount; i++) {
2249 			com_ungetc[i -1] = com_ungetc[i];
2250 		}
2251 		com_ungetccount--;
2252 		splx(s);
2253 		return (c);
2254 	}
2255 #endif
2256 
2257 	/* block until a character becomes available */
2258 	while (!ISSET(stat = bus_space_read_1(iot, ioh, com_lsr), LSR_RXRDY))
2259 		;
2260 
2261 	c = bus_space_read_1(iot, ioh, com_data);
2262 	stat = bus_space_read_1(iot, ioh, com_iir);
2263 #if defined(DDB) && defined(DDB_BREAK_CHAR)
2264 	if (c == DDB_BREAK_CHAR) {
2265 		extern int db_active;
2266 
2267 		if (db_active == 0) {
2268 			console_debugger();
2269 		}
2270 	}
2271 #endif
2272 	splx(s);
2273 	return (c);
2274 }
2275 
2276 void
2277 com_common_putc(iot, ioh, c)
2278 	bus_space_tag_t iot;
2279 	bus_space_handle_t ioh;
2280 	int c;
2281 {
2282 	int s = splserial();
2283 	int timo;
2284 
2285 #if defined(DDB) && defined(DDB_BREAK_CHAR)
2286 	int cin, stat;
2287 	if (com_ungetccount < MAX_UNGETC
2288 	     && ISSET(stat = bus_space_read_1(iot, ioh, com_lsr), LSR_RXRDY)) {
2289 		cin = bus_space_read_1(iot, ioh, com_data);
2290 		stat = bus_space_read_1(iot, ioh, com_iir);
2291 		if (cin == DDB_BREAK_CHAR) {
2292 			console_debugger();
2293 		}
2294 		com_ungetc[com_ungetccount++] = cin;
2295 	}
2296 #endif
2297 
2298 	/* wait for any pending transmission to finish */
2299 	timo = 150000;
2300 	while (!ISSET(bus_space_read_1(iot, ioh, com_lsr), LSR_TXRDY) && --timo)
2301 		continue;
2302 
2303 	bus_space_write_1(iot, ioh, com_data, c);
2304 	COM_BARRIER(iot, ioh, BR | BW);
2305 
2306 	/* wait for this transmission to complete */
2307 	timo = 1500000;
2308 	while (!ISSET(bus_space_read_1(iot, ioh, com_lsr), LSR_TXRDY) && --timo)
2309 		continue;
2310 
2311 	splx(s);
2312 }
2313 
2314 /*
2315  * Initialize UART for use as console or KGDB line.
2316  */
2317 int
2318 cominit(iot, iobase, rate, frequency, cflag, iohp)
2319 	bus_space_tag_t iot;
2320 	bus_addr_t iobase;
2321 	int rate, frequency;
2322 	tcflag_t cflag;
2323 	bus_space_handle_t *iohp;
2324 {
2325 	bus_space_handle_t ioh;
2326 
2327 	if (bus_space_map(iot, iobase, COM_NPORTS, 0, &ioh))
2328 		return (ENOMEM); /* ??? */
2329 
2330 	bus_space_write_1(iot, ioh, com_lcr, LCR_EERS);
2331 	bus_space_write_1(iot, ioh, com_efr, 0);
2332 	bus_space_write_1(iot, ioh, com_lcr, LCR_DLAB);
2333 	rate = comspeed(rate, frequency);
2334 	bus_space_write_1(iot, ioh, com_dlbl, rate);
2335 	bus_space_write_1(iot, ioh, com_dlbh, rate >> 8);
2336 	bus_space_write_1(iot, ioh, com_lcr, cflag2lcr(cflag));
2337 	bus_space_write_1(iot, ioh, com_mcr, MCR_DTR | MCR_RTS);
2338 	bus_space_write_1(iot, ioh, com_fifo,
2339 	    FIFO_ENABLE | FIFO_RCV_RST | FIFO_XMT_RST | FIFO_TRIGGER_1);
2340 	bus_space_write_1(iot, ioh, com_ier, 0);
2341 
2342 	*iohp = ioh;
2343 	return (0);
2344 }
2345 
2346 /*
2347  * Following are all routines needed for COM to act as console
2348  */
2349 struct consdev comcons = {
2350 	NULL, NULL, comcngetc, comcnputc, comcnpollc, NULL,
2351 	NODEV, CN_NORMAL
2352 };
2353 
2354 
2355 int
2356 comcnattach(iot, iobase, rate, frequency, cflag)
2357 	bus_space_tag_t iot;
2358 	bus_addr_t iobase;
2359 	int rate, frequency;
2360 	tcflag_t cflag;
2361 {
2362 	int res;
2363 
2364 	res = cominit(iot, iobase, rate, frequency, cflag, &comconsioh);
2365 	if (res)
2366 		return (res);
2367 
2368 	cn_tab = &comcons;
2369 
2370 	comconstag = iot;
2371 	comconsaddr = iobase;
2372 	comconsrate = rate;
2373 	comconscflag = cflag;
2374 
2375 	return (0);
2376 }
2377 
2378 int
2379 comcngetc(dev)
2380 	dev_t dev;
2381 {
2382 
2383 	return (com_common_getc(comconstag, comconsioh));
2384 }
2385 
2386 /*
2387  * Console kernel output character routine.
2388  */
2389 void
2390 comcnputc(dev, c)
2391 	dev_t dev;
2392 	int c;
2393 {
2394 
2395 	com_common_putc(comconstag, comconsioh, c);
2396 }
2397 
2398 void
2399 comcnpollc(dev, on)
2400 	dev_t dev;
2401 	int on;
2402 {
2403 
2404 }
2405 
2406 #ifdef KGDB
2407 int
2408 com_kgdb_attach(iot, iobase, rate, frequency, cflag)
2409 	bus_space_tag_t iot;
2410 	bus_addr_t iobase;
2411 	int rate, frequency;
2412 	tcflag_t cflag;
2413 {
2414 	int res;
2415 
2416 	if (iot == comconstag && iobase == comconsaddr)
2417 		return (EBUSY); /* cannot share with console */
2418 
2419 	res = cominit(iot, iobase, rate, frequency, cflag, &com_kgdb_ioh);
2420 	if (res)
2421 		return (res);
2422 
2423 	kgdb_attach(com_kgdb_getc, com_kgdb_putc, NULL);
2424 	kgdb_dev = 123; /* unneeded, only to satisfy some tests */
2425 
2426 	com_kgdb_iot = iot;
2427 	com_kgdb_addr = iobase;
2428 
2429 	return (0);
2430 }
2431 
2432 /* ARGSUSED */
2433 int
2434 com_kgdb_getc(arg)
2435 	void *arg;
2436 {
2437 
2438 	return (com_common_getc(com_kgdb_iot, com_kgdb_ioh));
2439 }
2440 
2441 /* ARGSUSED */
2442 void
2443 com_kgdb_putc(arg, c)
2444 	void *arg;
2445 	int c;
2446 {
2447 
2448 	return (com_common_putc(com_kgdb_iot, com_kgdb_ioh, c));
2449 }
2450 #endif /* KGDB */
2451 
2452 /* helper function to identify the com ports used by
2453  console or KGDB (and not yet autoconf attached) */
2454 int
2455 com_is_console(iot, iobase, ioh)
2456 	bus_space_tag_t iot;
2457 	bus_addr_t iobase;
2458 	bus_space_handle_t *ioh;
2459 {
2460 	bus_space_handle_t help;
2461 
2462 	if (!comconsattached &&
2463 	    iot == comconstag && iobase == comconsaddr)
2464 		help = comconsioh;
2465 #ifdef KGDB
2466 	else if (!com_kgdb_attached &&
2467 	    iot == com_kgdb_iot && iobase == com_kgdb_addr)
2468 		help = com_kgdb_ioh;
2469 #endif
2470 	else
2471 		return (0);
2472 
2473 	if (ioh)
2474 		*ioh = help;
2475 	return (1);
2476 }
2477