xref: /netbsd-src/sys/dev/ic/com.c (revision 4472dbe5e3bd91ef2540bada7a7ca7384627ff9b)
1 /*	$NetBSD: com.c,v 1.172 2000/05/03 19:19:04 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 /*
75  * COM driver, uses National Semiconductor NS16450/NS16550AF UART
76  * Supports automatic hardware flow control on StarTech ST16C650A UART
77  */
78 
79 #include "opt_ddb.h"
80 #include "opt_com.h"
81 
82 #include "rnd.h"
83 #if NRND > 0 && defined(RND_COM)
84 #include <sys/rnd.h>
85 #endif
86 
87 #include <sys/param.h>
88 #include <sys/systm.h>
89 #include <sys/ioctl.h>
90 #include <sys/select.h>
91 #include <sys/tty.h>
92 #include <sys/proc.h>
93 #include <sys/user.h>
94 #include <sys/conf.h>
95 #include <sys/file.h>
96 #include <sys/uio.h>
97 #include <sys/kernel.h>
98 #include <sys/syslog.h>
99 #include <sys/types.h>
100 #include <sys/device.h>
101 #include <sys/malloc.h>
102 #include <sys/timepps.h>
103 #include <sys/vnode.h>
104 
105 #include <machine/intr.h>
106 #include <machine/bus.h>
107 
108 #include <dev/ic/comreg.h>
109 #include <dev/ic/comvar.h>
110 #include <dev/ic/ns16550reg.h>
111 #include <dev/ic/st16650reg.h>
112 #ifdef COM_HAYESP
113 #include <dev/ic/hayespreg.h>
114 #endif
115 #define	com_lcr	com_cfcr
116 #include <dev/cons.h>
117 
118 #include "com.h"
119 
120 #ifdef COM_HAYESP
121 int comprobeHAYESP __P((bus_space_handle_t hayespioh, struct com_softc *sc));
122 #endif
123 
124 #if defined(DDB) || defined(KGDB)
125 static void com_enable_debugport __P((struct com_softc *));
126 #endif
127 void	com_config	__P((struct com_softc *));
128 void	com_shutdown	__P((struct com_softc *));
129 int	comspeed	__P((long, long));
130 static	u_char	cflag2lcr __P((tcflag_t));
131 int	comparam	__P((struct tty *, struct termios *));
132 void	comstart	__P((struct tty *));
133 void	comstop		__P((struct tty *, int));
134 int	comhwiflow	__P((struct tty *, int));
135 
136 void	com_loadchannelregs __P((struct com_softc *));
137 void	com_hwiflow	__P((struct com_softc *));
138 void	com_break	__P((struct com_softc *, int));
139 void	com_modem	__P((struct com_softc *, int));
140 void	tiocm_to_com	__P((struct com_softc *, int, int));
141 int	com_to_tiocm	__P((struct com_softc *));
142 void	com_iflush	__P((struct com_softc *));
143 
144 int	com_common_getc	__P((bus_space_tag_t, bus_space_handle_t));
145 void	com_common_putc	__P((bus_space_tag_t, bus_space_handle_t, int));
146 
147 /* XXX: These belong elsewhere */
148 cdev_decl(com);
149 bdev_decl(com);
150 
151 int	comcngetc	__P((dev_t));
152 void	comcnputc	__P((dev_t, int));
153 void	comcnpollc	__P((dev_t, int));
154 
155 #define	integrate	static inline
156 #ifdef __GENERIC_SOFT_INTERRUPTS
157 void 	comsoft		__P((void *));
158 #else
159 #ifndef __NO_SOFT_SERIAL_INTERRUPT
160 void 	comsoft		__P((void));
161 #else
162 void 	comsoft		__P((void *));
163 struct callout comsoft_callout = CALLOUT_INITIALIZER;
164 #endif
165 #endif
166 integrate void com_rxsoft	__P((struct com_softc *, struct tty *));
167 integrate void com_txsoft	__P((struct com_softc *, struct tty *));
168 integrate void com_stsoft	__P((struct com_softc *, struct tty *));
169 integrate void com_schedrx	__P((struct com_softc *));
170 void	comdiag		__P((void *));
171 
172 extern struct cfdriver com_cd;
173 
174 /*
175  * Make this an option variable one can patch.
176  * But be warned:  this must be a power of 2!
177  */
178 u_int com_rbuf_size = COM_RING_SIZE;
179 
180 /* Stop input when 3/4 of the ring is full; restart when only 1/4 is full. */
181 u_int com_rbuf_hiwat = (COM_RING_SIZE * 1) / 4;
182 u_int com_rbuf_lowat = (COM_RING_SIZE * 3) / 4;
183 
184 static int	comconsaddr;
185 static bus_space_tag_t comconstag;
186 static bus_space_handle_t comconsioh;
187 static int	comconsattached;
188 static int comconsrate;
189 static tcflag_t comconscflag;
190 
191 static int ppscap =
192 	PPS_TSFMT_TSPEC |
193 	PPS_CAPTUREASSERT |
194 	PPS_CAPTURECLEAR |
195 #ifdef  PPS_SYNC
196 	PPS_HARDPPSONASSERT | PPS_HARDPPSONCLEAR |
197 #endif	/* PPS_SYNC */
198 	PPS_OFFSETASSERT | PPS_OFFSETCLEAR;
199 
200 #ifndef __GENERIC_SOFT_INTERRUPTS
201 #ifdef __NO_SOFT_SERIAL_INTERRUPT
202 volatile int	com_softintr_scheduled;
203 #endif
204 #endif
205 
206 #ifdef KGDB
207 #include <sys/kgdb.h>
208 
209 static int com_kgdb_addr;
210 static bus_space_tag_t com_kgdb_iot;
211 static bus_space_handle_t com_kgdb_ioh;
212 static int com_kgdb_attached;
213 
214 int	com_kgdb_getc __P((void *));
215 void	com_kgdb_putc __P((void *, int));
216 #endif /* KGDB */
217 
218 #define	COMUNIT_MASK	0x7ffff
219 #define	COMDIALOUT_MASK	0x80000
220 
221 #define	COMUNIT(x)	(minor(x) & COMUNIT_MASK)
222 #define	COMDIALOUT(x)	(minor(x) & COMDIALOUT_MASK)
223 
224 #define	COM_ISALIVE(sc)	((sc)->enabled != 0 && \
225 			 ISSET((sc)->sc_dev.dv_flags, DVF_ACTIVE))
226 
227 #define	BR	BUS_SPACE_BARRIER_READ
228 #define	BW	BUS_SPACE_BARRIER_WRITE
229 #define COM_BARRIER(t, h, f) bus_space_barrier((t), (h), 0, COM_NPORTS, (f))
230 
231 int
232 comspeed(speed, frequency)
233 	long speed, frequency;
234 {
235 #define	divrnd(n, q)	(((n)*2/(q)+1)/2)	/* divide and round off */
236 
237 	int x, err;
238 
239 #if 0
240 	if (speed == 0)
241 		return (0);
242 #endif
243 	if (speed <= 0)
244 		return (-1);
245 	x = divrnd(frequency / 16, speed);
246 	if (x <= 0)
247 		return (-1);
248 	err = divrnd(((quad_t)frequency) * 1000 / 16, speed * x) - 1000;
249 	if (err < 0)
250 		err = -err;
251 	if (err > COM_TOLERANCE)
252 		return (-1);
253 	return (x);
254 
255 #undef	divrnd
256 }
257 
258 #ifdef COM_DEBUG
259 int	com_debug = 0;
260 
261 void comstatus __P((struct com_softc *, char *));
262 void
263 comstatus(sc, str)
264 	struct com_softc *sc;
265 	char *str;
266 {
267 	struct tty *tp = sc->sc_tty;
268 
269 	printf("%s: %s %sclocal  %sdcd %sts_carr_on %sdtr %stx_stopped\n",
270 	    sc->sc_dev.dv_xname, str,
271 	    ISSET(tp->t_cflag, CLOCAL) ? "+" : "-",
272 	    ISSET(sc->sc_msr, MSR_DCD) ? "+" : "-",
273 	    ISSET(tp->t_state, TS_CARR_ON) ? "+" : "-",
274 	    ISSET(sc->sc_mcr, MCR_DTR) ? "+" : "-",
275 	    sc->sc_tx_stopped ? "+" : "-");
276 
277 	printf("%s: %s %scrtscts %scts %sts_ttstop  %srts %xrx_flags\n",
278 	    sc->sc_dev.dv_xname, str,
279 	    ISSET(tp->t_cflag, CRTSCTS) ? "+" : "-",
280 	    ISSET(sc->sc_msr, MSR_CTS) ? "+" : "-",
281 	    ISSET(tp->t_state, TS_TTSTOP) ? "+" : "-",
282 	    ISSET(sc->sc_mcr, MCR_RTS) ? "+" : "-",
283 	    sc->sc_rx_flags);
284 }
285 #endif
286 
287 int
288 comprobe1(iot, ioh)
289 	bus_space_tag_t iot;
290 	bus_space_handle_t ioh;
291 {
292 
293 	/* force access to id reg */
294 	bus_space_write_1(iot, ioh, com_lcr, LCR_8BITS);
295 	bus_space_write_1(iot, ioh, com_iir, 0);
296 	if ((bus_space_read_1(iot, ioh, com_lcr) != LCR_8BITS) ||
297 	    (bus_space_read_1(iot, ioh, com_iir) & 0x38))
298 		return (0);
299 
300 	return (1);
301 }
302 
303 #ifdef COM_HAYESP
304 int
305 comprobeHAYESP(hayespioh, sc)
306 	bus_space_handle_t hayespioh;
307 	struct com_softc *sc;
308 {
309 	char	val, dips;
310 	int	combaselist[] = { 0x3f8, 0x2f8, 0x3e8, 0x2e8 };
311 	bus_space_tag_t iot = sc->sc_iot;
312 
313 	/*
314 	 * Hayes ESP cards have two iobases.  One is for compatibility with
315 	 * 16550 serial chips, and at the same ISA PC base addresses.  The
316 	 * other is for ESP-specific enhanced features, and lies at a
317 	 * different addressing range entirely (0x140, 0x180, 0x280, or 0x300).
318 	 */
319 
320 	/* Test for ESP signature */
321 	if ((bus_space_read_1(iot, hayespioh, 0) & 0xf3) == 0)
322 		return (0);
323 
324 	/*
325 	 * ESP is present at ESP enhanced base address; unknown com port
326 	 */
327 
328 	/* Get the dip-switch configurations */
329 	bus_space_write_1(iot, hayespioh, HAYESP_CMD1, HAYESP_GETDIPS);
330 	dips = bus_space_read_1(iot, hayespioh, HAYESP_STATUS1);
331 
332 	/* Determine which com port this ESP card services: bits 0,1 of  */
333 	/*  dips is the port # (0-3); combaselist[val] is the com_iobase */
334 	if (sc->sc_iobase != combaselist[dips & 0x03])
335 		return (0);
336 
337 	printf(": ESP");
338 
339  	/* Check ESP Self Test bits. */
340 	/* Check for ESP version 2.0: bits 4,5,6 == 010 */
341 	bus_space_write_1(iot, hayespioh, HAYESP_CMD1, HAYESP_GETTEST);
342 	val = bus_space_read_1(iot, hayespioh, HAYESP_STATUS1); /* Clear reg1 */
343 	val = bus_space_read_1(iot, hayespioh, HAYESP_STATUS2);
344 	if ((val & 0x70) < 0x20) {
345 		printf("-old (%o)", val & 0x70);
346 		/* we do not support the necessary features */
347 		return (0);
348 	}
349 
350 	/* Check for ability to emulate 16550: bit 8 == 1 */
351 	if ((dips & 0x80) == 0) {
352 		printf(" slave");
353 		/* XXX Does slave really mean no 16550 support?? */
354 		return (0);
355 	}
356 
357 	/*
358 	 * If we made it this far, we are a full-featured ESP v2.0 (or
359 	 * better), at the correct com port address.
360 	 */
361 
362 	SET(sc->sc_hwflags, COM_HW_HAYESP);
363 	printf(", 1024 byte fifo\n");
364 	return (1);
365 }
366 #endif
367 
368 #if defined(DDB) || defined(KGDB)
369 static void
370 com_enable_debugport(sc)
371 	struct com_softc *sc;
372 {
373 	int s;
374 
375 	/* Turn on line break interrupt, set carrier. */
376 	s = splserial();
377 	sc->sc_ier = IER_ERXRDY;
378 	bus_space_write_1(sc->sc_iot, sc->sc_ioh, com_ier, sc->sc_ier);
379 	SET(sc->sc_mcr, MCR_DTR | MCR_RTS);
380 	bus_space_write_1(sc->sc_iot, sc->sc_ioh, com_mcr, sc->sc_mcr);
381 	splx(s);
382 }
383 #endif
384 
385 void
386 com_attach_subr(sc)
387 	struct com_softc *sc;
388 {
389 	int iobase = sc->sc_iobase;
390 	bus_space_tag_t iot = sc->sc_iot;
391 	bus_space_handle_t ioh = sc->sc_ioh;
392 	struct tty *tp;
393 #ifdef COM16650
394 	u_int8_t lcr;
395 #endif
396 #ifdef COM_HAYESP
397 	int	hayesp_ports[] = { 0x140, 0x180, 0x280, 0x300, 0 };
398 	int	*hayespp;
399 #endif
400 
401 	callout_init(&sc->sc_diag_callout);
402 
403 	/* Disable interrupts before configuring the device. */
404 	sc->sc_ier = 0;
405 	bus_space_write_1(iot, ioh, com_ier, sc->sc_ier);
406 
407 	if (iot == comconstag && iobase == comconsaddr) {
408 		comconsattached = 1;
409 
410 		/* Make sure the console is always "hardwired". */
411 		delay(1000);			/* wait for output to finish */
412 		SET(sc->sc_hwflags, COM_HW_CONSOLE);
413 		SET(sc->sc_swflags, TIOCFLAG_SOFTCAR);
414 	}
415 
416 #ifdef COM_HAYESP
417 	/* Look for a Hayes ESP board. */
418 	for (hayespp = hayesp_ports; *hayespp != 0; hayespp++) {
419 		bus_space_handle_t hayespioh;
420 
421 #define	HAYESP_NPORTS	8			/* XXX XXX XXX ??? ??? ??? */
422 		if (bus_space_map(iot, *hayespp, HAYESP_NPORTS, 0, &hayespioh))
423 			continue;
424 		if (comprobeHAYESP(hayespioh, sc)) {
425 			sc->sc_hayespioh = hayespioh;
426 			sc->sc_fifolen = 1024;
427 
428 			break;
429 		}
430 		bus_space_unmap(iot, hayespioh, HAYESP_NPORTS);
431 	}
432 	/* No ESP; look for other things. */
433 	if (!ISSET(sc->sc_hwflags, COM_HW_HAYESP)) {
434 #endif
435 	sc->sc_fifolen = 1;
436 	/* look for a NS 16550AF UART with FIFOs */
437 	bus_space_write_1(iot, ioh, com_fifo,
438 	    FIFO_ENABLE | FIFO_RCV_RST | FIFO_XMT_RST | FIFO_TRIGGER_14);
439 	delay(100);
440 	if (ISSET(bus_space_read_1(iot, ioh, com_iir), IIR_FIFO_MASK)
441 	    == IIR_FIFO_MASK)
442 		if (ISSET(bus_space_read_1(iot, ioh, com_fifo), FIFO_TRIGGER_14)
443 		    == FIFO_TRIGGER_14) {
444 			SET(sc->sc_hwflags, COM_HW_FIFO);
445 
446 #ifdef COM16650
447 			/*
448 			 * IIR changes into the EFR if LCR is set to LCR_EERS
449 			 * on 16650s. We also know IIR != 0 at this point.
450 			 * Write 0 into the EFR, and read it. If the result
451 			 * is 0, we have a 16650.
452 			 *
453 			 * Older 16650s were broken; the test to detect them
454 			 * is taken from the Linux driver. Apparently
455 			 * setting DLAB enable gives access to the EFR on
456 			 * these chips.
457 			 */
458 			lcr = bus_space_read_1(iot, ioh, com_lcr);
459 			bus_space_write_1(iot, ioh, com_lcr, LCR_EERS);
460 			bus_space_write_1(iot, ioh, com_efr, 0);
461 			if (bus_space_read_1(iot, ioh, com_efr) == 0) {
462 				bus_space_write_1(iot, ioh, com_lcr,
463 				    lcr | LCR_DLAB);
464 				if (bus_space_read_1(iot, ioh, com_efr) == 0) {
465 					CLR(sc->sc_hwflags, COM_HW_FIFO);
466 					sc->sc_fifolen = 0;
467 				} else {
468 					SET(sc->sc_hwflags, COM_HW_FLOW);
469 					sc->sc_fifolen = 32;
470 				}
471 			} else
472 #endif
473 				sc->sc_fifolen = 16;
474 
475 #ifdef COM16650
476 			bus_space_write_1(iot, ioh, com_lcr, lcr);
477 			if (sc->sc_fifolen == 0)
478 				printf(": st16650, broken fifo\n");
479 			else if (sc->sc_fifolen == 32)
480 				printf(": st16650a, working fifo\n");
481 			else
482 #endif
483 				printf(": ns16550a, working fifo\n");
484 		} else
485 			printf(": ns16550, broken fifo\n");
486 	else
487 		printf(": ns8250 or ns16450, no fifo\n");
488 	bus_space_write_1(iot, ioh, com_fifo, 0);
489 	if (ISSET(sc->sc_hwflags, COM_HW_TXFIFO_DISABLE)) {
490 		sc->sc_fifolen = 1;
491 		printf("%s: txfifo disabled\n", sc->sc_dev.dv_xname);
492 	}
493 #ifdef COM_HAYESP
494 	}
495 #endif
496 
497 	tp = ttymalloc();
498 	tp->t_oproc = comstart;
499 	tp->t_param = comparam;
500 	tp->t_hwiflow = comhwiflow;
501 
502 	sc->sc_tty = tp;
503 	sc->sc_rbuf = malloc(com_rbuf_size << 1, M_DEVBUF, M_NOWAIT);
504 	if (sc->sc_rbuf == NULL) {
505 		printf("%s: unable to allocate ring buffer\n",
506 		    sc->sc_dev.dv_xname);
507 		return;
508 	}
509 	sc->sc_ebuf = sc->sc_rbuf + (com_rbuf_size << 1);
510 
511 	tty_attach(tp);
512 
513 	if (!ISSET(sc->sc_hwflags, COM_HW_NOIEN))
514 		SET(sc->sc_mcr, MCR_IENABLE);
515 
516 	if (ISSET(sc->sc_hwflags, COM_HW_CONSOLE)) {
517 		int maj;
518 
519 		/* locate the major number */
520 		for (maj = 0; maj < nchrdev; maj++)
521 			if (cdevsw[maj].d_open == comopen)
522 				break;
523 
524 		cn_tab->cn_dev = makedev(maj, sc->sc_dev.dv_unit);
525 
526 		printf("%s: console\n", sc->sc_dev.dv_xname);
527 	}
528 
529 #ifdef KGDB
530 	/*
531 	 * Allow kgdb to "take over" this port.  If this is
532 	 * the kgdb device, it has exclusive use.
533 	 */
534 	if (iot == com_kgdb_iot && iobase == com_kgdb_addr) {
535 		com_kgdb_attached = 1;
536 
537 		SET(sc->sc_hwflags, COM_HW_KGDB);
538 		printf("%s: kgdb\n", sc->sc_dev.dv_xname);
539 	}
540 #endif
541 
542 #ifdef __GENERIC_SOFT_INTERRUPTS
543 	sc->sc_si = softintr_establish(IPL_SOFTSERIAL, comsoft, sc);
544 #endif
545 
546 #if NRND > 0 && defined(RND_COM)
547 	rnd_attach_source(&sc->rnd_source, sc->sc_dev.dv_xname,
548 			  RND_TYPE_TTY, 0);
549 #endif
550 
551 	/* if there are no enable/disable functions, assume the device
552 	   is always enabled */
553 	if (!sc->enable)
554 		sc->enabled = 1;
555 
556 	com_config(sc);
557 
558 	SET(sc->sc_hwflags, COM_HW_DEV_OK);
559 }
560 
561 void
562 com_config(sc)
563 	struct com_softc *sc;
564 {
565 	bus_space_tag_t iot = sc->sc_iot;
566 	bus_space_handle_t ioh = sc->sc_ioh;
567 
568 	/* Disable interrupts before configuring the device. */
569 	sc->sc_ier = 0;
570 	bus_space_write_1(iot, ioh, com_ier, sc->sc_ier);
571 
572 #ifdef COM_HAYESP
573 	/* Look for a Hayes ESP board. */
574 	if (ISSET(sc->sc_hwflags, COM_HW_HAYESP)) {
575 		sc->sc_fifolen = 1024;
576 
577 		/* Set 16550 compatibility mode */
578 		bus_space_write_1(iot, sc->sc_hayespioh, HAYESP_CMD1,
579 				  HAYESP_SETMODE);
580 		bus_space_write_1(iot, sc->sc_hayespioh, HAYESP_CMD2,
581 				  HAYESP_MODE_FIFO|HAYESP_MODE_RTS|
582 				  HAYESP_MODE_SCALE);
583 
584 		/* Set RTS/CTS flow control */
585 		bus_space_write_1(iot, sc->sc_hayespioh, HAYESP_CMD1,
586 				  HAYESP_SETFLOWTYPE);
587 		bus_space_write_1(iot, sc->sc_hayespioh, HAYESP_CMD2,
588 				  HAYESP_FLOW_RTS);
589 		bus_space_write_1(iot, sc->sc_hayespioh, HAYESP_CMD2,
590 				  HAYESP_FLOW_CTS);
591 
592 		/* Set flow control levels */
593 		bus_space_write_1(iot, sc->sc_hayespioh, HAYESP_CMD1,
594 				  HAYESP_SETRXFLOW);
595 		bus_space_write_1(iot, sc->sc_hayespioh, HAYESP_CMD2,
596 				  HAYESP_HIBYTE(HAYESP_RXHIWMARK));
597 		bus_space_write_1(iot, sc->sc_hayespioh, HAYESP_CMD2,
598 				  HAYESP_LOBYTE(HAYESP_RXHIWMARK));
599 		bus_space_write_1(iot, sc->sc_hayespioh, HAYESP_CMD2,
600 				  HAYESP_HIBYTE(HAYESP_RXLOWMARK));
601 		bus_space_write_1(iot, sc->sc_hayespioh, HAYESP_CMD2,
602 				  HAYESP_LOBYTE(HAYESP_RXLOWMARK));
603 	}
604 #endif
605 
606 #ifdef DDB
607 	if (ISSET(sc->sc_hwflags, COM_HW_CONSOLE))
608 		com_enable_debugport(sc);
609 #endif
610 
611 #ifdef KGDB
612 	/*
613 	 * Allow kgdb to "take over" this port.  If this is
614 	 * the kgdb device, it has exclusive use.
615 	 */
616 	if (ISSET(sc->sc_hwflags, COM_HW_KGDB))
617 		com_enable_debugport(sc);
618 #endif
619 }
620 
621 int
622 com_detach(self, flags)
623 	struct device *self;
624 	int flags;
625 {
626 	struct com_softc *sc = (struct com_softc *)self;
627 	int maj, mn;
628 
629 	/* locate the major number */
630 	for (maj = 0; maj < nchrdev; maj++)
631 		if (cdevsw[maj].d_open == comopen)
632 			break;
633 
634 	/* Nuke the vnodes for any open instances. */
635 	mn = self->dv_unit;
636 	vdevgone(maj, mn, mn, VCHR);
637 
638 	mn |= COMDIALOUT_MASK;
639 	vdevgone(maj, mn, mn, VCHR);
640 
641 	/* Free the receive buffer. */
642 	free(sc->sc_rbuf, M_DEVBUF);
643 
644 	/* Detach and free the tty. */
645 	tty_detach(sc->sc_tty);
646 	ttyfree(sc->sc_tty);
647 
648 #ifdef __GENERIC_SOFT_INTERRUPTS
649 	/* Unhook the soft interrupt handler. */
650 	softintr_disestablish(sc->sc_si);
651 #endif
652 
653 #if NRND > 0 && defined(RND_COM)
654 	/* Unhook the entropy source. */
655 	rnd_detach_source(&sc->rnd_source);
656 #endif
657 
658 	return (0);
659 }
660 
661 int
662 com_activate(self, act)
663 	struct device *self;
664 	enum devact act;
665 {
666 	struct com_softc *sc = (struct com_softc *)self;
667 	int s, rv = 0;
668 
669 	s = splserial();
670 	switch (act) {
671 	case DVACT_ACTIVATE:
672 		rv = EOPNOTSUPP;
673 		break;
674 
675 	case DVACT_DEACTIVATE:
676 		if (sc->sc_hwflags & (COM_HW_CONSOLE|COM_HW_KGDB)) {
677 			rv = EBUSY;
678 			break;
679 		}
680 
681 		if (sc->disable != NULL && sc->enabled != 0) {
682 			(*sc->disable)(sc);
683 			sc->enabled = 0;
684 		}
685 		break;
686 	}
687 	splx(s);
688 	return (rv);
689 }
690 
691 void
692 com_shutdown(sc)
693 	struct com_softc *sc;
694 {
695 	struct tty *tp = sc->sc_tty;
696 	int s;
697 
698 	s = splserial();
699 
700 	/* If we were asserting flow control, then deassert it. */
701 	SET(sc->sc_rx_flags, RX_IBUF_BLOCKED);
702 	com_hwiflow(sc);
703 
704 	/* Clear any break condition set with TIOCSBRK. */
705 	com_break(sc, 0);
706 
707 	/* Turn off PPS capture on last close. */
708 	sc->sc_ppsmask = 0;
709 	sc->ppsparam.mode = 0;
710 
711 	/*
712 	 * Hang up if necessary.  Wait a bit, so the other side has time to
713 	 * notice even if we immediately open the port again.
714 	 */
715 	if (ISSET(tp->t_cflag, HUPCL)) {
716 		com_modem(sc, 0);
717 		(void) tsleep(sc, TTIPRI, ttclos, hz);
718 	}
719 
720 	/* Turn off interrupts. */
721 #ifdef DDB
722 	if (ISSET(sc->sc_hwflags, COM_HW_CONSOLE))
723 		sc->sc_ier = IER_ERXRDY; /* interrupt on break */
724 	else
725 #endif
726 		sc->sc_ier = 0;
727 	bus_space_write_1(sc->sc_iot, sc->sc_ioh, com_ier, sc->sc_ier);
728 
729 	if (sc->disable) {
730 #ifdef DIAGNOSTIC
731 		if (!sc->enabled)
732 			panic("com_shutdown: not enabled?");
733 #endif
734 		(*sc->disable)(sc);
735 		sc->enabled = 0;
736 	}
737 
738 	splx(s);
739 }
740 
741 int
742 comopen(dev, flag, mode, p)
743 	dev_t dev;
744 	int flag, mode;
745 	struct proc *p;
746 {
747 	int unit = COMUNIT(dev);
748 	struct com_softc *sc;
749 	struct tty *tp;
750 	int s, s2;
751 	int error;
752 
753 	if (unit >= com_cd.cd_ndevs)
754 		return (ENXIO);
755 	sc = com_cd.cd_devs[unit];
756 	if (sc == 0 || !ISSET(sc->sc_hwflags, COM_HW_DEV_OK) ||
757 	    sc->sc_rbuf == NULL)
758 		return (ENXIO);
759 
760 	if (ISSET(sc->sc_dev.dv_flags, DVF_ACTIVE) == 0)
761 		return (ENXIO);
762 
763 #ifdef KGDB
764 	/*
765 	 * If this is the kgdb port, no other use is permitted.
766 	 */
767 	if (ISSET(sc->sc_hwflags, COM_HW_KGDB))
768 		return (EBUSY);
769 #endif
770 
771 	tp = sc->sc_tty;
772 
773 	if (ISSET(tp->t_state, TS_ISOPEN) &&
774 	    ISSET(tp->t_state, TS_XCLUDE) &&
775 	    p->p_ucred->cr_uid != 0)
776 		return (EBUSY);
777 
778 	s = spltty();
779 
780 	/*
781 	 * Do the following iff this is a first open.
782 	 */
783 	if (!ISSET(tp->t_state, TS_ISOPEN) && tp->t_wopen == 0) {
784 		struct termios t;
785 
786 		tp->t_dev = dev;
787 
788 		s2 = splserial();
789 
790 		if (sc->enable) {
791 			if ((*sc->enable)(sc)) {
792 				splx(s2);
793 				splx(s);
794 				printf("%s: device enable failed\n",
795 				       sc->sc_dev.dv_xname);
796 				return (EIO);
797 			}
798 			sc->enabled = 1;
799 			com_config(sc);
800 		}
801 
802 		/* Turn on interrupts. */
803 		sc->sc_ier = IER_ERXRDY | IER_ERLS | IER_EMSC;
804 		bus_space_write_1(sc->sc_iot, sc->sc_ioh, com_ier, sc->sc_ier);
805 
806 		/* Fetch the current modem control status, needed later. */
807 		sc->sc_msr = bus_space_read_1(sc->sc_iot, sc->sc_ioh, com_msr);
808 
809 		/* Clear PPS capture state on first open. */
810 		sc->sc_ppsmask = 0;
811 		sc->ppsparam.mode = 0;
812 
813 		splx(s2);
814 
815 		/*
816 		 * Initialize the termios status to the defaults.  Add in the
817 		 * sticky bits from TIOCSFLAGS.
818 		 */
819 		t.c_ispeed = 0;
820 		if (ISSET(sc->sc_hwflags, COM_HW_CONSOLE)) {
821 			t.c_ospeed = comconsrate;
822 			t.c_cflag = comconscflag;
823 		} else {
824 			t.c_ospeed = TTYDEF_SPEED;
825 			t.c_cflag = TTYDEF_CFLAG;
826 		}
827 		if (ISSET(sc->sc_swflags, TIOCFLAG_CLOCAL))
828 			SET(t.c_cflag, CLOCAL);
829 		if (ISSET(sc->sc_swflags, TIOCFLAG_CRTSCTS))
830 			SET(t.c_cflag, CRTSCTS);
831 		if (ISSET(sc->sc_swflags, TIOCFLAG_MDMBUF))
832 			SET(t.c_cflag, MDMBUF);
833 		/* Make sure comparam() will do something. */
834 		tp->t_ospeed = 0;
835 		(void) comparam(tp, &t);
836 		tp->t_iflag = TTYDEF_IFLAG;
837 		tp->t_oflag = TTYDEF_OFLAG;
838 		tp->t_lflag = TTYDEF_LFLAG;
839 		ttychars(tp);
840 		ttsetwater(tp);
841 
842 		s2 = splserial();
843 
844 		/*
845 		 * Turn on DTR.  We must always do this, even if carrier is not
846 		 * present, because otherwise we'd have to use TIOCSDTR
847 		 * immediately after setting CLOCAL, which applications do not
848 		 * expect.  We always assert DTR while the device is open
849 		 * unless explicitly requested to deassert it.
850 		 */
851 		com_modem(sc, 1);
852 
853 		/* Clear the input ring, and unblock. */
854 		sc->sc_rbput = sc->sc_rbget = sc->sc_rbuf;
855 		sc->sc_rbavail = com_rbuf_size;
856 		com_iflush(sc);
857 		CLR(sc->sc_rx_flags, RX_ANY_BLOCK);
858 		com_hwiflow(sc);
859 
860 #ifdef COM_DEBUG
861 		if (com_debug)
862 			comstatus(sc, "comopen  ");
863 #endif
864 
865 		splx(s2);
866 	}
867 
868 	splx(s);
869 
870 	error = ttyopen(tp, COMDIALOUT(dev), ISSET(flag, O_NONBLOCK));
871 	if (error)
872 		goto bad;
873 
874 	error = (*linesw[tp->t_line].l_open)(dev, tp);
875 	if (error)
876 		goto bad;
877 
878 	return (0);
879 
880 bad:
881 	if (!ISSET(tp->t_state, TS_ISOPEN) && tp->t_wopen == 0) {
882 		/*
883 		 * We failed to open the device, and nobody else had it opened.
884 		 * Clean up the state as appropriate.
885 		 */
886 		com_shutdown(sc);
887 	}
888 
889 	return (error);
890 }
891 
892 int
893 comclose(dev, flag, mode, p)
894 	dev_t dev;
895 	int flag, mode;
896 	struct proc *p;
897 {
898 	struct com_softc *sc = com_cd.cd_devs[COMUNIT(dev)];
899 	struct tty *tp = sc->sc_tty;
900 
901 	/* XXX This is for cons.c. */
902 	if (!ISSET(tp->t_state, TS_ISOPEN))
903 		return (0);
904 
905 	(*linesw[tp->t_line].l_close)(tp, flag);
906 	ttyclose(tp);
907 
908 	if (COM_ISALIVE(sc) == 0)
909 		return (0);
910 
911 	if (!ISSET(tp->t_state, TS_ISOPEN) && tp->t_wopen == 0) {
912 		/*
913 		 * Although we got a last close, the device may still be in
914 		 * use; e.g. if this was the dialout node, and there are still
915 		 * processes waiting for carrier on the non-dialout node.
916 		 */
917 		com_shutdown(sc);
918 	}
919 
920 	return (0);
921 }
922 
923 int
924 comread(dev, uio, flag)
925 	dev_t dev;
926 	struct uio *uio;
927 	int flag;
928 {
929 	struct com_softc *sc = com_cd.cd_devs[COMUNIT(dev)];
930 	struct tty *tp = sc->sc_tty;
931 
932 	if (COM_ISALIVE(sc) == 0)
933 		return (EIO);
934 
935 	return ((*linesw[tp->t_line].l_read)(tp, uio, flag));
936 }
937 
938 int
939 comwrite(dev, uio, flag)
940 	dev_t dev;
941 	struct uio *uio;
942 	int flag;
943 {
944 	struct com_softc *sc = com_cd.cd_devs[COMUNIT(dev)];
945 	struct tty *tp = sc->sc_tty;
946 
947 	if (COM_ISALIVE(sc) == 0)
948 		return (EIO);
949 
950 	return ((*linesw[tp->t_line].l_write)(tp, uio, flag));
951 }
952 
953 struct tty *
954 comtty(dev)
955 	dev_t dev;
956 {
957 	struct com_softc *sc = com_cd.cd_devs[COMUNIT(dev)];
958 	struct tty *tp = sc->sc_tty;
959 
960 	return (tp);
961 }
962 
963 int
964 comioctl(dev, cmd, data, flag, p)
965 	dev_t dev;
966 	u_long cmd;
967 	caddr_t data;
968 	int flag;
969 	struct proc *p;
970 {
971 	struct com_softc *sc = com_cd.cd_devs[COMUNIT(dev)];
972 	struct tty *tp = sc->sc_tty;
973 	int error;
974 	int s;
975 
976 	if (COM_ISALIVE(sc) == 0)
977 		return (EIO);
978 
979 	error = (*linesw[tp->t_line].l_ioctl)(tp, cmd, data, flag, p);
980 	if (error >= 0)
981 		return (error);
982 
983 	error = ttioctl(tp, cmd, data, flag, p);
984 	if (error >= 0)
985 		return (error);
986 
987 	error = 0;
988 
989 	s = splserial();
990 
991 	switch (cmd) {
992 	case TIOCSBRK:
993 		com_break(sc, 1);
994 		break;
995 
996 	case TIOCCBRK:
997 		com_break(sc, 0);
998 		break;
999 
1000 	case TIOCSDTR:
1001 		com_modem(sc, 1);
1002 		break;
1003 
1004 	case TIOCCDTR:
1005 		com_modem(sc, 0);
1006 		break;
1007 
1008 	case TIOCGFLAGS:
1009 		*(int *)data = sc->sc_swflags;
1010 		break;
1011 
1012 	case TIOCSFLAGS:
1013 		error = suser(p->p_ucred, &p->p_acflag);
1014 		if (error)
1015 			break;
1016 		sc->sc_swflags = *(int *)data;
1017 		break;
1018 
1019 	case TIOCMSET:
1020 	case TIOCMBIS:
1021 	case TIOCMBIC:
1022 		tiocm_to_com(sc, cmd, *(int *)data);
1023 		break;
1024 
1025 	case TIOCMGET:
1026 		*(int *)data = com_to_tiocm(sc);
1027 		break;
1028 
1029 	case PPS_IOC_CREATE:
1030 		break;
1031 
1032 	case PPS_IOC_DESTROY:
1033 		break;
1034 
1035 	case PPS_IOC_GETPARAMS: {
1036 		pps_params_t *pp;
1037 		pp = (pps_params_t *)data;
1038 		*pp = sc->ppsparam;
1039 		break;
1040 	}
1041 
1042 	case PPS_IOC_SETPARAMS: {
1043 	  	pps_params_t *pp;
1044 		int mode;
1045 		pp = (pps_params_t *)data;
1046 		if (pp->mode & ~ppscap) {
1047 			error = EINVAL;
1048 			break;
1049 		}
1050 		sc->ppsparam = *pp;
1051 	 	/*
1052 		 * Compute msr masks from user-specified timestamp state.
1053 		 */
1054 		mode = sc->ppsparam.mode;
1055 #ifdef	PPS_SYNC
1056 		if (mode & PPS_HARDPPSONASSERT) {
1057 			mode |= PPS_CAPTUREASSERT;
1058 			/* XXX revoke any previous HARDPPS source */
1059 		}
1060 		if (mode & PPS_HARDPPSONCLEAR) {
1061 			mode |= PPS_CAPTURECLEAR;
1062 			/* XXX revoke any previous HARDPPS source */
1063 		}
1064 #endif	/* PPS_SYNC */
1065 		switch (mode & PPS_CAPTUREBOTH) {
1066 		case 0:
1067 			sc->sc_ppsmask = 0;
1068 			break;
1069 
1070 		case PPS_CAPTUREASSERT:
1071 			sc->sc_ppsmask = MSR_DCD;
1072 			sc->sc_ppsassert = MSR_DCD;
1073 			sc->sc_ppsclear = -1;
1074 			break;
1075 
1076 		case PPS_CAPTURECLEAR:
1077 			sc->sc_ppsmask = MSR_DCD;
1078 			sc->sc_ppsassert = -1;
1079 			sc->sc_ppsclear = 0;
1080 			break;
1081 
1082 		case PPS_CAPTUREBOTH:
1083 			sc->sc_ppsmask = MSR_DCD;
1084 			sc->sc_ppsassert = MSR_DCD;
1085 			sc->sc_ppsclear = 0;
1086 			break;
1087 
1088 		default:
1089 			error = EINVAL;
1090 			break;
1091 		}
1092 		break;
1093 	}
1094 
1095 	case PPS_IOC_GETCAP:
1096 		*(int*)data = ppscap;
1097 		break;
1098 
1099 	case PPS_IOC_FETCH: {
1100 		pps_info_t *pi;
1101 		pi = (pps_info_t *)data;
1102 		*pi = sc->ppsinfo;
1103 		break;
1104 	}
1105 
1106 	case TIOCDCDTIMESTAMP:	/* XXX old, overloaded  API used by xntpd v3 */
1107 		/*
1108 		 * Some GPS clocks models use the falling rather than
1109 		 * rising edge as the on-the-second signal.
1110 		 * The old API has no way to specify PPS polarity.
1111 		 */
1112 		sc->sc_ppsmask = MSR_DCD;
1113 #ifndef PPS_TRAILING_EDGE
1114 		sc->sc_ppsassert = MSR_DCD;
1115 		sc->sc_ppsclear = -1;
1116 		TIMESPEC_TO_TIMEVAL((struct timeval *)data,
1117 		    &sc->ppsinfo.assert_timestamp);
1118 #else
1119 		sc->sc_ppsassert = -1
1120 		sc->sc_ppsclear = 0;
1121 		TIMESPEC_TO_TIMEVAL((struct timeval *)data,
1122 		    &sc->ppsinfo.clear_timestamp);
1123 #endif
1124 		break;
1125 
1126 	default:
1127 		error = ENOTTY;
1128 		break;
1129 	}
1130 
1131 	splx(s);
1132 
1133 #ifdef COM_DEBUG
1134 	if (com_debug)
1135 		comstatus(sc, "comioctl ");
1136 #endif
1137 
1138 	return (error);
1139 }
1140 
1141 integrate void
1142 com_schedrx(sc)
1143 	struct com_softc *sc;
1144 {
1145 
1146 	sc->sc_rx_ready = 1;
1147 
1148 	/* Wake up the poller. */
1149 #ifdef __GENERIC_SOFT_INTERRUPTS
1150 	softintr_schedule(sc->sc_si);
1151 #else
1152 #ifndef __NO_SOFT_SERIAL_INTERRUPT
1153 	setsoftserial();
1154 #else
1155 	if (!com_softintr_scheduled) {
1156 		com_softintr_scheduled = 1;
1157 		callout_reset(&comsoft_callout, 1, comsoft, NULL);
1158 	}
1159 #endif
1160 #endif
1161 }
1162 
1163 void
1164 com_break(sc, onoff)
1165 	struct com_softc *sc;
1166 	int onoff;
1167 {
1168 
1169 	if (onoff)
1170 		SET(sc->sc_lcr, LCR_SBREAK);
1171 	else
1172 		CLR(sc->sc_lcr, LCR_SBREAK);
1173 
1174 	if (!sc->sc_heldchange) {
1175 		if (sc->sc_tx_busy) {
1176 			sc->sc_heldtbc = sc->sc_tbc;
1177 			sc->sc_tbc = 0;
1178 			sc->sc_heldchange = 1;
1179 		} else
1180 			com_loadchannelregs(sc);
1181 	}
1182 }
1183 
1184 void
1185 com_modem(sc, onoff)
1186 	struct com_softc *sc;
1187 	int onoff;
1188 {
1189 
1190 	if (sc->sc_mcr_dtr == 0)
1191 		return;
1192 
1193 	if (onoff)
1194 		SET(sc->sc_mcr, sc->sc_mcr_dtr);
1195 	else
1196 		CLR(sc->sc_mcr, sc->sc_mcr_dtr);
1197 
1198 	if (!sc->sc_heldchange) {
1199 		if (sc->sc_tx_busy) {
1200 			sc->sc_heldtbc = sc->sc_tbc;
1201 			sc->sc_tbc = 0;
1202 			sc->sc_heldchange = 1;
1203 		} else
1204 			com_loadchannelregs(sc);
1205 	}
1206 }
1207 
1208 void
1209 tiocm_to_com(sc, how, ttybits)
1210 	struct com_softc *sc;
1211 	int how, ttybits;
1212 {
1213 	u_char combits;
1214 
1215 	combits = 0;
1216 	if (ISSET(ttybits, TIOCM_DTR))
1217 		SET(combits, MCR_DTR);
1218 	if (ISSET(ttybits, TIOCM_RTS))
1219 		SET(combits, MCR_RTS);
1220 
1221 	switch (how) {
1222 	case TIOCMBIC:
1223 		CLR(sc->sc_mcr, combits);
1224 		break;
1225 
1226 	case TIOCMBIS:
1227 		SET(sc->sc_mcr, combits);
1228 		break;
1229 
1230 	case TIOCMSET:
1231 		CLR(sc->sc_mcr, MCR_DTR | MCR_RTS);
1232 		SET(sc->sc_mcr, combits);
1233 		break;
1234 	}
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 int
1247 com_to_tiocm(sc)
1248 	struct com_softc *sc;
1249 {
1250 	u_char combits;
1251 	int ttybits = 0;
1252 
1253 	combits = sc->sc_mcr;
1254 	if (ISSET(combits, MCR_DTR))
1255 		SET(ttybits, TIOCM_DTR);
1256 	if (ISSET(combits, MCR_RTS))
1257 		SET(ttybits, TIOCM_RTS);
1258 
1259 	combits = sc->sc_msr;
1260 	if (ISSET(combits, MSR_DCD))
1261 		SET(ttybits, TIOCM_CD);
1262 	if (ISSET(combits, MSR_CTS))
1263 		SET(ttybits, TIOCM_CTS);
1264 	if (ISSET(combits, MSR_DSR))
1265 		SET(ttybits, TIOCM_DSR);
1266 	if (ISSET(combits, MSR_RI | MSR_TERI))
1267 		SET(ttybits, TIOCM_RI);
1268 
1269 	if (sc->sc_ier != 0)
1270 		SET(ttybits, TIOCM_LE);
1271 
1272 	return (ttybits);
1273 }
1274 
1275 static u_char
1276 cflag2lcr(cflag)
1277 	tcflag_t cflag;
1278 {
1279 	u_char lcr = 0;
1280 
1281 	switch (ISSET(cflag, CSIZE)) {
1282 	case CS5:
1283 		SET(lcr, LCR_5BITS);
1284 		break;
1285 	case CS6:
1286 		SET(lcr, LCR_6BITS);
1287 		break;
1288 	case CS7:
1289 		SET(lcr, LCR_7BITS);
1290 		break;
1291 	case CS8:
1292 		SET(lcr, LCR_8BITS);
1293 		break;
1294 	}
1295 	if (ISSET(cflag, PARENB)) {
1296 		SET(lcr, LCR_PENAB);
1297 		if (!ISSET(cflag, PARODD))
1298 			SET(lcr, LCR_PEVEN);
1299 	}
1300 	if (ISSET(cflag, CSTOPB))
1301 		SET(lcr, LCR_STOPB);
1302 
1303 	return (lcr);
1304 }
1305 
1306 int
1307 comparam(tp, t)
1308 	struct tty *tp;
1309 	struct termios *t;
1310 {
1311 	struct com_softc *sc = com_cd.cd_devs[COMUNIT(tp->t_dev)];
1312 	int ospeed = comspeed(t->c_ospeed, sc->sc_frequency);
1313 	u_char lcr;
1314 	int s;
1315 
1316 	if (COM_ISALIVE(sc) == 0)
1317 		return (EIO);
1318 
1319 	/* Check requested parameters. */
1320 	if (ospeed < 0)
1321 		return (EINVAL);
1322 	if (t->c_ispeed && t->c_ispeed != t->c_ospeed)
1323 		return (EINVAL);
1324 
1325 	/*
1326 	 * For the console, always force CLOCAL and !HUPCL, so that the port
1327 	 * is always active.
1328 	 */
1329 	if (ISSET(sc->sc_swflags, TIOCFLAG_SOFTCAR) ||
1330 	    ISSET(sc->sc_hwflags, COM_HW_CONSOLE)) {
1331 		SET(t->c_cflag, CLOCAL);
1332 		CLR(t->c_cflag, HUPCL);
1333 	}
1334 
1335 	/*
1336 	 * If there were no changes, don't do anything.  This avoids dropping
1337 	 * input and improves performance when all we did was frob things like
1338 	 * VMIN and VTIME.
1339 	 */
1340 	if (tp->t_ospeed == t->c_ospeed &&
1341 	    tp->t_cflag == t->c_cflag)
1342 		return (0);
1343 
1344 	lcr = ISSET(sc->sc_lcr, LCR_SBREAK) | cflag2lcr(t->c_cflag);
1345 
1346 	s = splserial();
1347 
1348 	sc->sc_lcr = lcr;
1349 
1350 	/*
1351 	 * If we're not in a mode that assumes a connection is present, then
1352 	 * ignore carrier changes.
1353 	 */
1354 	if (ISSET(t->c_cflag, CLOCAL | MDMBUF))
1355 		sc->sc_msr_dcd = 0;
1356 	else
1357 		sc->sc_msr_dcd = MSR_DCD;
1358 	/*
1359 	 * Set the flow control pins depending on the current flow control
1360 	 * mode.
1361 	 */
1362 	if (ISSET(t->c_cflag, CRTSCTS)) {
1363 		sc->sc_mcr_dtr = MCR_DTR;
1364 		sc->sc_mcr_rts = MCR_RTS;
1365 		sc->sc_msr_cts = MSR_CTS;
1366 		sc->sc_efr = EFR_AUTORTS | EFR_AUTOCTS;
1367 	} else if (ISSET(t->c_cflag, MDMBUF)) {
1368 		/*
1369 		 * For DTR/DCD flow control, make sure we don't toggle DTR for
1370 		 * carrier detection.
1371 		 */
1372 		sc->sc_mcr_dtr = 0;
1373 		sc->sc_mcr_rts = MCR_DTR;
1374 		sc->sc_msr_cts = MSR_DCD;
1375 		sc->sc_efr = 0;
1376 	} else {
1377 		/*
1378 		 * If no flow control, then always set RTS.  This will make
1379 		 * the other side happy if it mistakenly thinks we're doing
1380 		 * RTS/CTS flow control.
1381 		 */
1382 		sc->sc_mcr_dtr = MCR_DTR | MCR_RTS;
1383 		sc->sc_mcr_rts = 0;
1384 		sc->sc_msr_cts = 0;
1385 		sc->sc_efr = 0;
1386 		if (ISSET(sc->sc_mcr, MCR_DTR))
1387 			SET(sc->sc_mcr, MCR_RTS);
1388 		else
1389 			CLR(sc->sc_mcr, MCR_RTS);
1390 	}
1391 	sc->sc_msr_mask = sc->sc_msr_cts | sc->sc_msr_dcd;
1392 
1393 #if 0
1394 	if (ospeed == 0)
1395 		CLR(sc->sc_mcr, sc->sc_mcr_dtr);
1396 	else
1397 		SET(sc->sc_mcr, sc->sc_mcr_dtr);
1398 #endif
1399 
1400 	sc->sc_dlbl = ospeed;
1401 	sc->sc_dlbh = ospeed >> 8;
1402 
1403 	/*
1404 	 * Set the FIFO threshold based on the receive speed.
1405 	 *
1406 	 *  * If it's a low speed, it's probably a mouse or some other
1407 	 *    interactive device, so set the threshold low.
1408 	 *  * If it's a high speed, trim the trigger level down to prevent
1409 	 *    overflows.
1410 	 *  * Otherwise set it a bit higher.
1411 	 */
1412 	if (ISSET(sc->sc_hwflags, COM_HW_HAYESP))
1413 		sc->sc_fifo = FIFO_DMA_MODE | FIFO_ENABLE | FIFO_TRIGGER_8;
1414 	else if (ISSET(sc->sc_hwflags, COM_HW_FIFO))
1415 		sc->sc_fifo = FIFO_ENABLE |
1416 		    (t->c_ospeed <= 1200 ? FIFO_TRIGGER_1 :
1417 		     t->c_ospeed <= 38400 ? FIFO_TRIGGER_8 : FIFO_TRIGGER_4);
1418 	else
1419 		sc->sc_fifo = 0;
1420 
1421 	/* And copy to tty. */
1422 	tp->t_ispeed = 0;
1423 	tp->t_ospeed = t->c_ospeed;
1424 	tp->t_cflag = t->c_cflag;
1425 
1426 	if (!sc->sc_heldchange) {
1427 		if (sc->sc_tx_busy) {
1428 			sc->sc_heldtbc = sc->sc_tbc;
1429 			sc->sc_tbc = 0;
1430 			sc->sc_heldchange = 1;
1431 		} else
1432 			com_loadchannelregs(sc);
1433 	}
1434 
1435 	if (!ISSET(t->c_cflag, CHWFLOW)) {
1436 		/* Disable the high water mark. */
1437 		sc->sc_r_hiwat = 0;
1438 		sc->sc_r_lowat = 0;
1439 		if (ISSET(sc->sc_rx_flags, RX_TTY_OVERFLOWED)) {
1440 			CLR(sc->sc_rx_flags, RX_TTY_OVERFLOWED);
1441 			com_schedrx(sc);
1442 		}
1443 		if (ISSET(sc->sc_rx_flags, RX_TTY_BLOCKED|RX_IBUF_BLOCKED)) {
1444 			CLR(sc->sc_rx_flags, RX_TTY_BLOCKED|RX_IBUF_BLOCKED);
1445 			com_hwiflow(sc);
1446 		}
1447 	} else {
1448 		sc->sc_r_hiwat = com_rbuf_hiwat;
1449 		sc->sc_r_lowat = com_rbuf_lowat;
1450 	}
1451 
1452 	splx(s);
1453 
1454 	/*
1455 	 * Update the tty layer's idea of the carrier bit, in case we changed
1456 	 * CLOCAL or MDMBUF.  We don't hang up here; we only do that by
1457 	 * explicit request.
1458 	 */
1459 	(void) (*linesw[tp->t_line].l_modem)(tp, ISSET(sc->sc_msr, MSR_DCD));
1460 
1461 #ifdef COM_DEBUG
1462 	if (com_debug)
1463 		comstatus(sc, "comparam ");
1464 #endif
1465 
1466 	if (!ISSET(t->c_cflag, CHWFLOW)) {
1467 		if (sc->sc_tx_stopped) {
1468 			sc->sc_tx_stopped = 0;
1469 			comstart(tp);
1470 		}
1471 	}
1472 
1473 	return (0);
1474 }
1475 
1476 void
1477 com_iflush(sc)
1478 	struct com_softc *sc;
1479 {
1480 	bus_space_tag_t iot = sc->sc_iot;
1481 	bus_space_handle_t ioh = sc->sc_ioh;
1482 #ifdef DIAGNOSTIC
1483 	int reg;
1484 #endif
1485 	int timo;
1486 
1487 #ifdef DIAGNOSTIC
1488 	reg = 0xffff;
1489 #endif
1490 	timo = 50000;
1491 	/* flush any pending I/O */
1492 	while (ISSET(bus_space_read_1(iot, ioh, com_lsr), LSR_RXRDY)
1493 	    && --timo)
1494 #ifdef DIAGNOSTIC
1495 		reg =
1496 #else
1497 		    (void)
1498 #endif
1499 		    bus_space_read_1(iot, ioh, com_data);
1500 #ifdef DIAGNOSTIC
1501 	if (!timo)
1502 		printf("%s: com_iflush timeout %02x\n", sc->sc_dev.dv_xname,
1503 		       reg);
1504 #endif
1505 }
1506 
1507 void
1508 com_loadchannelregs(sc)
1509 	struct com_softc *sc;
1510 {
1511 	bus_space_tag_t iot = sc->sc_iot;
1512 	bus_space_handle_t ioh = sc->sc_ioh;
1513 
1514 	/* XXXXX necessary? */
1515 	com_iflush(sc);
1516 
1517 	bus_space_write_1(iot, ioh, com_ier, 0);
1518 
1519 	if (ISSET(sc->sc_hwflags, COM_HW_FLOW)) {
1520 		bus_space_write_1(iot, ioh, com_lcr, LCR_EERS);
1521 		bus_space_write_1(iot, ioh, com_efr, sc->sc_efr);
1522 	}
1523 	bus_space_write_1(iot, ioh, com_lcr, sc->sc_lcr | LCR_DLAB);
1524 	bus_space_write_1(iot, ioh, com_dlbl, sc->sc_dlbl);
1525 	bus_space_write_1(iot, ioh, com_dlbh, sc->sc_dlbh);
1526 	bus_space_write_1(iot, ioh, com_lcr, sc->sc_lcr);
1527 	bus_space_write_1(iot, ioh, com_mcr, sc->sc_mcr_active = sc->sc_mcr);
1528 	bus_space_write_1(iot, ioh, com_fifo, sc->sc_fifo);
1529 
1530 	bus_space_write_1(iot, ioh, com_ier, sc->sc_ier);
1531 }
1532 
1533 int
1534 comhwiflow(tp, block)
1535 	struct tty *tp;
1536 	int block;
1537 {
1538 	struct com_softc *sc = com_cd.cd_devs[COMUNIT(tp->t_dev)];
1539 	int s;
1540 
1541 	if (COM_ISALIVE(sc) == 0)
1542 		return (0);
1543 
1544 	if (sc->sc_mcr_rts == 0)
1545 		return (0);
1546 
1547 	s = splserial();
1548 	if (block) {
1549 		if (!ISSET(sc->sc_rx_flags, RX_TTY_BLOCKED)) {
1550 			SET(sc->sc_rx_flags, RX_TTY_BLOCKED);
1551 			com_hwiflow(sc);
1552 		}
1553 	} else {
1554 		if (ISSET(sc->sc_rx_flags, RX_TTY_OVERFLOWED)) {
1555 			CLR(sc->sc_rx_flags, RX_TTY_OVERFLOWED);
1556 			com_schedrx(sc);
1557 		}
1558 		if (ISSET(sc->sc_rx_flags, RX_TTY_BLOCKED)) {
1559 			CLR(sc->sc_rx_flags, RX_TTY_BLOCKED);
1560 			com_hwiflow(sc);
1561 		}
1562 	}
1563 	splx(s);
1564 	return (1);
1565 }
1566 
1567 /*
1568  * (un)block input via hw flowcontrol
1569  */
1570 void
1571 com_hwiflow(sc)
1572 	struct com_softc *sc;
1573 {
1574 	bus_space_tag_t iot = sc->sc_iot;
1575 	bus_space_handle_t ioh = sc->sc_ioh;
1576 
1577 	if (sc->sc_mcr_rts == 0)
1578 		return;
1579 
1580 	if (ISSET(sc->sc_rx_flags, RX_ANY_BLOCK)) {
1581 		CLR(sc->sc_mcr, sc->sc_mcr_rts);
1582 		CLR(sc->sc_mcr_active, sc->sc_mcr_rts);
1583 	} else {
1584 		SET(sc->sc_mcr, sc->sc_mcr_rts);
1585 		SET(sc->sc_mcr_active, sc->sc_mcr_rts);
1586 	}
1587 	bus_space_write_1(iot, ioh, com_mcr, sc->sc_mcr_active);
1588 }
1589 
1590 
1591 void
1592 comstart(tp)
1593 	struct tty *tp;
1594 {
1595 	struct com_softc *sc = com_cd.cd_devs[COMUNIT(tp->t_dev)];
1596 	bus_space_tag_t iot = sc->sc_iot;
1597 	bus_space_handle_t ioh = sc->sc_ioh;
1598 	int s;
1599 
1600 	if (COM_ISALIVE(sc) == 0)
1601 		return;
1602 
1603 	s = spltty();
1604 	if (ISSET(tp->t_state, TS_BUSY | TS_TIMEOUT | TS_TTSTOP))
1605 		goto out;
1606 	if (sc->sc_tx_stopped)
1607 		goto out;
1608 
1609 	if (tp->t_outq.c_cc <= tp->t_lowat) {
1610 		if (ISSET(tp->t_state, TS_ASLEEP)) {
1611 			CLR(tp->t_state, TS_ASLEEP);
1612 			wakeup(&tp->t_outq);
1613 		}
1614 		selwakeup(&tp->t_wsel);
1615 		if (tp->t_outq.c_cc == 0)
1616 			goto out;
1617 	}
1618 
1619 	/* Grab the first contiguous region of buffer space. */
1620 	{
1621 		u_char *tba;
1622 		int tbc;
1623 
1624 		tba = tp->t_outq.c_cf;
1625 		tbc = ndqb(&tp->t_outq, 0);
1626 
1627 		(void)splserial();
1628 
1629 		sc->sc_tba = tba;
1630 		sc->sc_tbc = tbc;
1631 	}
1632 
1633 	SET(tp->t_state, TS_BUSY);
1634 	sc->sc_tx_busy = 1;
1635 
1636 	/* Enable transmit completion interrupts if necessary. */
1637 	if (!ISSET(sc->sc_ier, IER_ETXRDY)) {
1638 		SET(sc->sc_ier, IER_ETXRDY);
1639 		bus_space_write_1(iot, ioh, com_ier, sc->sc_ier);
1640 	}
1641 
1642 	/* Output the first chunk of the contiguous buffer. */
1643 	{
1644 		int n;
1645 
1646 		n = sc->sc_tbc;
1647 		if (n > sc->sc_fifolen)
1648 			n = sc->sc_fifolen;
1649 		bus_space_write_multi_1(iot, ioh, com_data, sc->sc_tba, n);
1650 		sc->sc_tbc -= n;
1651 		sc->sc_tba += n;
1652 	}
1653 out:
1654 	splx(s);
1655 	return;
1656 }
1657 
1658 /*
1659  * Stop output on a line.
1660  */
1661 void
1662 comstop(tp, flag)
1663 	struct tty *tp;
1664 	int flag;
1665 {
1666 	struct com_softc *sc = com_cd.cd_devs[COMUNIT(tp->t_dev)];
1667 	int s;
1668 
1669 	s = splserial();
1670 	if (ISSET(tp->t_state, TS_BUSY)) {
1671 		/* Stop transmitting at the next chunk. */
1672 		sc->sc_tbc = 0;
1673 		sc->sc_heldtbc = 0;
1674 		if (!ISSET(tp->t_state, TS_TTSTOP))
1675 			SET(tp->t_state, TS_FLUSH);
1676 	}
1677 	splx(s);
1678 }
1679 
1680 void
1681 comdiag(arg)
1682 	void *arg;
1683 {
1684 	struct com_softc *sc = arg;
1685 	int overflows, floods;
1686 	int s;
1687 
1688 	s = splserial();
1689 	overflows = sc->sc_overflows;
1690 	sc->sc_overflows = 0;
1691 	floods = sc->sc_floods;
1692 	sc->sc_floods = 0;
1693 	sc->sc_errors = 0;
1694 	splx(s);
1695 
1696 	log(LOG_WARNING, "%s: %d silo overflow%s, %d ibuf flood%s\n",
1697 	    sc->sc_dev.dv_xname,
1698 	    overflows, overflows == 1 ? "" : "s",
1699 	    floods, floods == 1 ? "" : "s");
1700 }
1701 
1702 integrate void
1703 com_rxsoft(sc, tp)
1704 	struct com_softc *sc;
1705 	struct tty *tp;
1706 {
1707 	int (*rint) __P((int c, struct tty *tp)) = linesw[tp->t_line].l_rint;
1708 	u_char *get, *end;
1709 	u_int cc, scc;
1710 	u_char lsr;
1711 	int code;
1712 	int s;
1713 
1714 	end = sc->sc_ebuf;
1715 	get = sc->sc_rbget;
1716 	scc = cc = com_rbuf_size - sc->sc_rbavail;
1717 
1718 	if (cc == com_rbuf_size) {
1719 		sc->sc_floods++;
1720 		if (sc->sc_errors++ == 0)
1721 			callout_reset(&sc->sc_diag_callout, 60 * hz,
1722 			    comdiag, sc);
1723 	}
1724 
1725 	while (cc) {
1726 		code = get[0];
1727 		lsr = get[1];
1728 		if (ISSET(lsr, LSR_OE | LSR_BI | LSR_FE | LSR_PE)) {
1729 			if (ISSET(lsr, LSR_OE)) {
1730 				sc->sc_overflows++;
1731 				if (sc->sc_errors++ == 0)
1732 					callout_reset(&sc->sc_diag_callout,
1733 					    60 * hz, comdiag, sc);
1734 			}
1735 			if (ISSET(lsr, LSR_BI | LSR_FE))
1736 				SET(code, TTY_FE);
1737 			if (ISSET(lsr, LSR_PE))
1738 				SET(code, TTY_PE);
1739 		}
1740 		if ((*rint)(code, tp) == -1) {
1741 			/*
1742 			 * The line discipline's buffer is out of space.
1743 			 */
1744 			if (!ISSET(sc->sc_rx_flags, RX_TTY_BLOCKED)) {
1745 				/*
1746 				 * We're either not using flow control, or the
1747 				 * line discipline didn't tell us to block for
1748 				 * some reason.  Either way, we have no way to
1749 				 * know when there's more space available, so
1750 				 * just drop the rest of the data.
1751 				 */
1752 				get += cc << 1;
1753 				if (get >= end)
1754 					get -= com_rbuf_size << 1;
1755 				cc = 0;
1756 			} else {
1757 				/*
1758 				 * Don't schedule any more receive processing
1759 				 * until the line discipline tells us there's
1760 				 * space available (through comhwiflow()).
1761 				 * Leave the rest of the data in the input
1762 				 * buffer.
1763 				 */
1764 				SET(sc->sc_rx_flags, RX_TTY_OVERFLOWED);
1765 			}
1766 			break;
1767 		}
1768 		get += 2;
1769 		if (get >= end)
1770 			get = sc->sc_rbuf;
1771 		cc--;
1772 	}
1773 
1774 	if (cc != scc) {
1775 		sc->sc_rbget = get;
1776 		s = splserial();
1777 		cc = sc->sc_rbavail += scc - cc;
1778 		/* Buffers should be ok again, release possible block. */
1779 		if (cc >= sc->sc_r_lowat) {
1780 			if (ISSET(sc->sc_rx_flags, RX_IBUF_OVERFLOWED)) {
1781 				CLR(sc->sc_rx_flags, RX_IBUF_OVERFLOWED);
1782 				SET(sc->sc_ier, IER_ERXRDY);
1783 				bus_space_write_1(sc->sc_iot, sc->sc_ioh, com_ier, sc->sc_ier);
1784 			}
1785 			if (ISSET(sc->sc_rx_flags, RX_IBUF_BLOCKED)) {
1786 				CLR(sc->sc_rx_flags, RX_IBUF_BLOCKED);
1787 				com_hwiflow(sc);
1788 			}
1789 		}
1790 		splx(s);
1791 	}
1792 }
1793 
1794 integrate void
1795 com_txsoft(sc, tp)
1796 	struct com_softc *sc;
1797 	struct tty *tp;
1798 {
1799 
1800 	CLR(tp->t_state, TS_BUSY);
1801 	if (ISSET(tp->t_state, TS_FLUSH))
1802 		CLR(tp->t_state, TS_FLUSH);
1803 	else
1804 		ndflush(&tp->t_outq, (int)(sc->sc_tba - tp->t_outq.c_cf));
1805 	(*linesw[tp->t_line].l_start)(tp);
1806 }
1807 
1808 integrate void
1809 com_stsoft(sc, tp)
1810 	struct com_softc *sc;
1811 	struct tty *tp;
1812 {
1813 	u_char msr, delta;
1814 	int s;
1815 
1816 	s = splserial();
1817 	msr = sc->sc_msr;
1818 	delta = sc->sc_msr_delta;
1819 	sc->sc_msr_delta = 0;
1820 	splx(s);
1821 
1822 	if (ISSET(delta, sc->sc_msr_dcd)) {
1823 		/*
1824 		 * Inform the tty layer that carrier detect changed.
1825 		 */
1826 		(void) (*linesw[tp->t_line].l_modem)(tp, ISSET(msr, MSR_DCD));
1827 	}
1828 
1829 	if (ISSET(delta, sc->sc_msr_cts)) {
1830 		/* Block or unblock output according to flow control. */
1831 		if (ISSET(msr, sc->sc_msr_cts)) {
1832 			sc->sc_tx_stopped = 0;
1833 			(*linesw[tp->t_line].l_start)(tp);
1834 		} else {
1835 			sc->sc_tx_stopped = 1;
1836 		}
1837 	}
1838 
1839 #ifdef COM_DEBUG
1840 	if (com_debug)
1841 		comstatus(sc, "com_stsoft");
1842 #endif
1843 }
1844 
1845 #ifdef __GENERIC_SOFT_INTERRUPTS
1846 void
1847 comsoft(arg)
1848 	void *arg;
1849 {
1850 	struct com_softc *sc = arg;
1851 	struct tty *tp;
1852 
1853 	if (COM_ISALIVE(sc) == 0)
1854 		return;
1855 
1856 	{
1857 #else
1858 void
1859 #ifndef __NO_SOFT_SERIAL_INTERRUPT
1860 comsoft()
1861 #else
1862 comsoft(arg)
1863 	void *arg;
1864 #endif
1865 {
1866 	struct com_softc	*sc;
1867 	struct tty	*tp;
1868 	int	unit;
1869 #ifdef __NO_SOFT_SERIAL_INTERRUPT
1870 	int s;
1871 
1872 	s = splsoftserial();
1873 	com_softintr_scheduled = 0;
1874 #endif
1875 
1876 	for (unit = 0; unit < com_cd.cd_ndevs; unit++) {
1877 		sc = com_cd.cd_devs[unit];
1878 		if (sc == NULL || !ISSET(sc->sc_hwflags, COM_HW_DEV_OK))
1879 			continue;
1880 
1881 		if (COM_ISALIVE(sc) == 0)
1882 			continue;
1883 
1884 		tp = sc->sc_tty;
1885 		if (tp == NULL)
1886 			continue;
1887 		if (!ISSET(tp->t_state, TS_ISOPEN) && tp->t_wopen == 0)
1888 			continue;
1889 #endif
1890 		tp = sc->sc_tty;
1891 
1892 		if (sc->sc_rx_ready) {
1893 			sc->sc_rx_ready = 0;
1894 			com_rxsoft(sc, tp);
1895 		}
1896 
1897 		if (sc->sc_st_check) {
1898 			sc->sc_st_check = 0;
1899 			com_stsoft(sc, tp);
1900 		}
1901 
1902 		if (sc->sc_tx_done) {
1903 			sc->sc_tx_done = 0;
1904 			com_txsoft(sc, tp);
1905 		}
1906 	}
1907 
1908 #ifndef __GENERIC_SOFT_INTERRUPTS
1909 #ifdef __NO_SOFT_SERIAL_INTERRUPT
1910 	splx(s);
1911 #endif
1912 #endif
1913 }
1914 
1915 #ifdef __ALIGN_BRACKET_LEVEL_FOR_CTAGS
1916 	/* there has got to be a better way to do comsoft() */
1917 }}
1918 #endif
1919 
1920 int
1921 comintr(arg)
1922 	void *arg;
1923 {
1924 	struct com_softc *sc = arg;
1925 	bus_space_tag_t iot = sc->sc_iot;
1926 	bus_space_handle_t ioh = sc->sc_ioh;
1927 	u_char *put, *end;
1928 	u_int cc;
1929 	u_char lsr, iir;
1930 
1931 	if (COM_ISALIVE(sc) == 0)
1932 		return (0);
1933 
1934 	iir = bus_space_read_1(iot, ioh, com_iir);
1935 	if (ISSET(iir, IIR_NOPEND))
1936 		return (0);
1937 
1938 	end = sc->sc_ebuf;
1939 	put = sc->sc_rbput;
1940 	cc = sc->sc_rbavail;
1941 
1942 	do {
1943 		u_char	msr, delta;
1944 
1945 		lsr = bus_space_read_1(iot, ioh, com_lsr);
1946 #if defined(DDB) || defined(KGDB)
1947 		if (ISSET(lsr, LSR_BI)) {
1948 #ifdef DDB
1949 			if (ISSET(sc->sc_hwflags, COM_HW_CONSOLE)) {
1950 				console_debugger();
1951 				continue;
1952 			}
1953 #endif
1954 #ifdef KGDB
1955 			if (ISSET(sc->sc_hwflags, COM_HW_KGDB)) {
1956 				kgdb_connect(1);
1957 				continue;
1958 			}
1959 #endif
1960 		}
1961 #endif /* DDB || KGDB */
1962 
1963 		if (ISSET(lsr, LSR_RCV_MASK) &&
1964 		    !ISSET(sc->sc_rx_flags, RX_IBUF_OVERFLOWED)) {
1965 			while (cc > 0) {
1966 				put[0] = bus_space_read_1(iot, ioh, com_data);
1967 				put[1] = lsr;
1968 				put += 2;
1969 				if (put >= end)
1970 					put = sc->sc_rbuf;
1971 				cc--;
1972 
1973 				lsr = bus_space_read_1(iot, ioh, com_lsr);
1974 				if (!ISSET(lsr, LSR_RCV_MASK))
1975 					break;
1976 			}
1977 
1978 			/*
1979 			 * Current string of incoming characters ended because
1980 			 * no more data was available or we ran out of space.
1981 			 * Schedule a receive event if any data was received.
1982 			 * If we're out of space, turn off receive interrupts.
1983 			 */
1984 			sc->sc_rbput = put;
1985 			sc->sc_rbavail = cc;
1986 			if (!ISSET(sc->sc_rx_flags, RX_TTY_OVERFLOWED))
1987 				sc->sc_rx_ready = 1;
1988 
1989 			/*
1990 			 * See if we are in danger of overflowing a buffer. If
1991 			 * so, use hardware flow control to ease the pressure.
1992 			 */
1993 			if (!ISSET(sc->sc_rx_flags, RX_IBUF_BLOCKED) &&
1994 			    cc < sc->sc_r_hiwat) {
1995 				SET(sc->sc_rx_flags, RX_IBUF_BLOCKED);
1996 				com_hwiflow(sc);
1997 			}
1998 
1999 			/*
2000 			 * If we're out of space, disable receive interrupts
2001 			 * until the queue has drained a bit.
2002 			 */
2003 			if (!cc) {
2004 				SET(sc->sc_rx_flags, RX_IBUF_OVERFLOWED);
2005 				CLR(sc->sc_ier, IER_ERXRDY);
2006 				bus_space_write_1(iot, ioh, com_ier, sc->sc_ier);
2007 			}
2008 		} else {
2009 			if ((iir & IIR_IMASK) == IIR_RXRDY) {
2010 				bus_space_write_1(iot, ioh, com_ier, 0);
2011 				delay(10);
2012 				bus_space_write_1(iot, ioh, com_ier,sc->sc_ier);
2013 				iir = IIR_NOPEND;
2014 				continue;
2015 			}
2016 		}
2017 
2018 		msr = bus_space_read_1(iot, ioh, com_msr);
2019 		delta = msr ^ sc->sc_msr;
2020 		sc->sc_msr = msr;
2021 		/*
2022 		 * Pulse-per-second (PSS) signals on edge of DCD?
2023 		 * Process these even if line discipline is ignoring DCD.
2024 		 */
2025 		if (delta & sc->sc_ppsmask) {
2026 			struct timeval tv;
2027 		    	if ((msr & sc->sc_ppsmask) == sc->sc_ppsassert) {
2028 				/* XXX nanotime() */
2029 				microtime(&tv);
2030 				TIMEVAL_TO_TIMESPEC(&tv,
2031 				    &sc->ppsinfo.assert_timestamp);
2032 				if (sc->ppsparam.mode & PPS_OFFSETASSERT) {
2033 					timespecadd(&sc->ppsinfo.assert_timestamp,
2034 					    &sc->ppsparam.assert_offset,
2035 						    &sc->ppsinfo.assert_timestamp);
2036 				}
2037 
2038 #ifdef PPS_SYNC
2039 				if (sc->ppsparam.mode & PPS_HARDPPSONASSERT)
2040 					hardpps(&tv, tv.tv_usec);
2041 #endif
2042 				sc->ppsinfo.assert_sequence++;
2043 				sc->ppsinfo.current_mode = sc->ppsparam.mode;
2044 
2045 			} else if ((msr & sc->sc_ppsmask) == sc->sc_ppsclear) {
2046 				/* XXX nanotime() */
2047 				microtime(&tv);
2048 				TIMEVAL_TO_TIMESPEC(&tv,
2049 				    &sc->ppsinfo.clear_timestamp);
2050 				if (sc->ppsparam.mode & PPS_OFFSETCLEAR) {
2051 					timespecadd(&sc->ppsinfo.clear_timestamp,
2052 					    &sc->ppsparam.clear_offset,
2053 					    &sc->ppsinfo.clear_timestamp);
2054 				}
2055 
2056 #ifdef PPS_SYNC
2057 				if (sc->ppsparam.mode & PPS_HARDPPSONCLEAR)
2058 					hardpps(&tv, tv.tv_usec);
2059 #endif
2060 				sc->ppsinfo.clear_sequence++;
2061 				sc->ppsinfo.current_mode = sc->ppsparam.mode;
2062 			}
2063 		}
2064 
2065 		/*
2066 		 * Process normal status changes
2067 		 */
2068 		if (ISSET(delta, sc->sc_msr_mask)) {
2069 			SET(sc->sc_msr_delta, delta);
2070 
2071 			/*
2072 			 * Stop output immediately if we lose the output
2073 			 * flow control signal or carrier detect.
2074 			 */
2075 			if (ISSET(~msr, sc->sc_msr_mask)) {
2076 				sc->sc_tbc = 0;
2077 				sc->sc_heldtbc = 0;
2078 #ifdef COM_DEBUG
2079 				if (com_debug)
2080 					comstatus(sc, "comintr  ");
2081 #endif
2082 			}
2083 
2084 			sc->sc_st_check = 1;
2085 		}
2086 	} while (!ISSET((iir = bus_space_read_1(iot, ioh, com_iir)), IIR_NOPEND));
2087 
2088 	/*
2089 	 * Done handling any receive interrupts. See if data can be
2090 	 * transmitted as well. Schedule tx done event if no data left
2091 	 * and tty was marked busy.
2092 	 */
2093 	if (ISSET(lsr, LSR_TXRDY)) {
2094 		/*
2095 		 * If we've delayed a parameter change, do it now, and restart
2096 		 * output.
2097 		 */
2098 		if (sc->sc_heldchange) {
2099 			com_loadchannelregs(sc);
2100 			sc->sc_heldchange = 0;
2101 			sc->sc_tbc = sc->sc_heldtbc;
2102 			sc->sc_heldtbc = 0;
2103 		}
2104 
2105 		/* Output the next chunk of the contiguous buffer, if any. */
2106 		if (sc->sc_tbc > 0) {
2107 			int n;
2108 
2109 			n = sc->sc_tbc;
2110 			if (n > sc->sc_fifolen)
2111 				n = sc->sc_fifolen;
2112 			bus_space_write_multi_1(iot, ioh, com_data, sc->sc_tba, n);
2113 			sc->sc_tbc -= n;
2114 			sc->sc_tba += n;
2115 		} else {
2116 			/* Disable transmit completion interrupts if necessary. */
2117 			if (ISSET(sc->sc_ier, IER_ETXRDY)) {
2118 				CLR(sc->sc_ier, IER_ETXRDY);
2119 				bus_space_write_1(iot, ioh, com_ier, sc->sc_ier);
2120 			}
2121 			if (sc->sc_tx_busy) {
2122 				sc->sc_tx_busy = 0;
2123 				sc->sc_tx_done = 1;
2124 			}
2125 		}
2126 	}
2127 
2128 	/* Wake up the poller. */
2129 #ifdef __GENERIC_SOFT_INTERRUPTS
2130 	softintr_schedule(sc->sc_si);
2131 #else
2132 #ifndef __NO_SOFT_SERIAL_INTERRUPT
2133 	setsoftserial();
2134 #else
2135 	if (!com_softintr_scheduled) {
2136 		com_softintr_scheduled = 1;
2137 		callout_reset(&comsoft_callout, 1, comsoft, NULL);
2138 	}
2139 #endif
2140 #endif
2141 
2142 #if NRND > 0 && defined(RND_COM)
2143 	rnd_add_uint32(&sc->rnd_source, iir | lsr);
2144 #endif
2145 
2146 	return (1);
2147 }
2148 
2149 /*
2150  * The following functions are polled getc and putc routines, shared
2151  * by the console and kgdb glue.
2152  */
2153 
2154 int
2155 com_common_getc(iot, ioh)
2156 	bus_space_tag_t iot;
2157 	bus_space_handle_t ioh;
2158 {
2159 	int s = splserial();
2160 	u_char stat, c;
2161 
2162 	/* block until a character becomes available */
2163 	while (!ISSET(stat = bus_space_read_1(iot, ioh, com_lsr), LSR_RXRDY))
2164 		;
2165 
2166 	c = bus_space_read_1(iot, ioh, com_data);
2167 	stat = bus_space_read_1(iot, ioh, com_iir);
2168 	splx(s);
2169 	return (c);
2170 }
2171 
2172 void
2173 com_common_putc(iot, ioh, c)
2174 	bus_space_tag_t iot;
2175 	bus_space_handle_t ioh;
2176 	int c;
2177 {
2178 	int s = splserial();
2179 	int timo;
2180 
2181 	/* wait for any pending transmission to finish */
2182 	timo = 150000;
2183 	while (!ISSET(bus_space_read_1(iot, ioh, com_lsr), LSR_TXRDY) && --timo)
2184 		continue;
2185 
2186 	bus_space_write_1(iot, ioh, com_data, c);
2187 	COM_BARRIER(iot, ioh, BR | BW);
2188 
2189 	/* wait for this transmission to complete */
2190 	timo = 1500000;
2191 	while (!ISSET(bus_space_read_1(iot, ioh, com_lsr), LSR_TXRDY) && --timo)
2192 		continue;
2193 
2194 	splx(s);
2195 }
2196 
2197 /*
2198  * Initialize UART for use as console or KGDB line.
2199  */
2200 int
2201 cominit(iot, iobase, rate, frequency, cflag, iohp)
2202 	bus_space_tag_t iot;
2203 	int iobase;
2204 	int rate, frequency;
2205 	tcflag_t cflag;
2206 	bus_space_handle_t *iohp;
2207 {
2208 	bus_space_handle_t ioh;
2209 
2210 	if (bus_space_map(iot, iobase, COM_NPORTS, 0, &ioh))
2211 		return (ENOMEM); /* ??? */
2212 
2213 	bus_space_write_1(iot, ioh, com_lcr, LCR_EERS);
2214 	bus_space_write_1(iot, ioh, com_efr, 0);
2215 	bus_space_write_1(iot, ioh, com_lcr, LCR_DLAB);
2216 	rate = comspeed(rate, frequency);
2217 	bus_space_write_1(iot, ioh, com_dlbl, rate);
2218 	bus_space_write_1(iot, ioh, com_dlbh, rate >> 8);
2219 	bus_space_write_1(iot, ioh, com_lcr, cflag2lcr(cflag));
2220 	bus_space_write_1(iot, ioh, com_mcr, MCR_DTR | MCR_RTS);
2221 	bus_space_write_1(iot, ioh, com_fifo,
2222 	    FIFO_ENABLE | FIFO_RCV_RST | FIFO_XMT_RST | FIFO_TRIGGER_1);
2223 	bus_space_write_1(iot, ioh, com_ier, 0);
2224 
2225 	*iohp = ioh;
2226 	return (0);
2227 }
2228 
2229 /*
2230  * Following are all routines needed for COM to act as console
2231  */
2232 
2233 int
2234 comcnattach(iot, iobase, rate, frequency, cflag)
2235 	bus_space_tag_t iot;
2236 	int iobase;
2237 	int rate, frequency;
2238 	tcflag_t cflag;
2239 {
2240 	int res;
2241 	static struct consdev comcons = {
2242 		NULL, NULL, comcngetc, comcnputc, comcnpollc, NULL,
2243 		    NODEV, CN_NORMAL
2244 	};
2245 
2246 	res = cominit(iot, iobase, rate, frequency, cflag, &comconsioh);
2247 	if (res)
2248 		return (res);
2249 
2250 	cn_tab = &comcons;
2251 
2252 	comconstag = iot;
2253 	comconsaddr = iobase;
2254 	comconsrate = rate;
2255 	comconscflag = cflag;
2256 
2257 	return (0);
2258 }
2259 
2260 int
2261 comcngetc(dev)
2262 	dev_t dev;
2263 {
2264 
2265 	return (com_common_getc(comconstag, comconsioh));
2266 }
2267 
2268 /*
2269  * Console kernel output character routine.
2270  */
2271 void
2272 comcnputc(dev, c)
2273 	dev_t dev;
2274 	int c;
2275 {
2276 
2277 	com_common_putc(comconstag, comconsioh, c);
2278 }
2279 
2280 void
2281 comcnpollc(dev, on)
2282 	dev_t dev;
2283 	int on;
2284 {
2285 
2286 }
2287 
2288 #ifdef KGDB
2289 int
2290 com_kgdb_attach(iot, iobase, rate, frequency, cflag)
2291 	bus_space_tag_t iot;
2292 	int iobase;
2293 	int rate, frequency;
2294 	tcflag_t cflag;
2295 {
2296 	int res;
2297 
2298 	if (iot == comconstag && iobase == comconsaddr)
2299 		return (EBUSY); /* cannot share with console */
2300 
2301 	res = cominit(iot, iobase, rate, frequency, cflag, &com_kgdb_ioh);
2302 	if (res)
2303 		return (res);
2304 
2305 	kgdb_attach(com_kgdb_getc, com_kgdb_putc, NULL);
2306 	kgdb_dev = 123; /* unneeded, only to satisfy some tests */
2307 
2308 	com_kgdb_iot = iot;
2309 	com_kgdb_addr = iobase;
2310 
2311 	return (0);
2312 }
2313 
2314 /* ARGSUSED */
2315 int
2316 com_kgdb_getc(arg)
2317 	void *arg;
2318 {
2319 
2320 	return (com_common_getc(com_kgdb_iot, com_kgdb_ioh));
2321 }
2322 
2323 /* ARGSUSED */
2324 void
2325 com_kgdb_putc(arg, c)
2326 	void *arg;
2327 	int c;
2328 {
2329 
2330 	return (com_common_putc(com_kgdb_iot, com_kgdb_ioh, c));
2331 }
2332 #endif /* KGDB */
2333 
2334 /* helper function to identify the com ports used by
2335  console or KGDB (and not yet autoconf attached) */
2336 int
2337 com_is_console(iot, iobase, ioh)
2338 	bus_space_tag_t iot;
2339 	int iobase;
2340 	bus_space_handle_t *ioh;
2341 {
2342 	bus_space_handle_t help;
2343 
2344 	if (!comconsattached &&
2345 	    iot == comconstag && iobase == comconsaddr)
2346 		help = comconsioh;
2347 #ifdef KGDB
2348 	else if (!com_kgdb_attached &&
2349 	    iot == com_kgdb_iot && iobase == com_kgdb_addr)
2350 		help = com_kgdb_ioh;
2351 #endif
2352 	else
2353 		return (0);
2354 
2355 	if (ioh)
2356 		*ioh = help;
2357 	return (1);
2358 }
2359