xref: /netbsd-src/sys/dev/ic/com.c (revision d0fed6c87ddc40a8bffa6f99e7433ddfc864dd83)
1 /*	$NetBSD: com.c,v 1.99 1997/04/04 20:56:34 mycroft Exp $	*/
2 
3 /*-
4  * Copyright (c) 1993, 1994, 1995, 1996, 1997
5  *	Charles M. Hannum.  All rights reserved.
6  *
7  * Interrupt processing and hardware flow control partly based on code from
8  * Onno van der Linden and Gordon Ross.
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 Charles M. Hannum.
21  * 4. The name of the author may not be used to endorse or promote products
22  *    derived from this software without specific prior written permission.
23  *
24  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
25  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
26  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
27  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
28  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
29  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
30  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
31  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
32  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
33  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
34  */
35 
36 /*
37  * Copyright (c) 1991 The Regents of the University of California.
38  * All rights reserved.
39  *
40  * Redistribution and use in source and binary forms, with or without
41  * modification, are permitted provided that the following conditions
42  * are met:
43  * 1. Redistributions of source code must retain the above copyright
44  *    notice, this list of conditions and the following disclaimer.
45  * 2. Redistributions in binary form must reproduce the above copyright
46  *    notice, this list of conditions and the following disclaimer in the
47  *    documentation and/or other materials provided with the distribution.
48  * 3. All advertising materials mentioning features or use of this software
49  *    must display the following acknowledgement:
50  *	This product includes software developed by the University of
51  *	California, Berkeley and its contributors.
52  * 4. Neither the name of the University nor the names of its contributors
53  *    may be used to endorse or promote products derived from this software
54  *    without specific prior written permission.
55  *
56  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
57  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
58  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
59  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
60  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
61  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
62  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
63  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
64  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
65  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
66  * SUCH DAMAGE.
67  *
68  *	@(#)com.c	7.5 (Berkeley) 5/16/91
69  */
70 
71 /*
72  * COM driver, uses National Semiconductor NS16450/NS16550AF UART
73  */
74 #include <sys/param.h>
75 #include <sys/systm.h>
76 #include <sys/ioctl.h>
77 #include <sys/select.h>
78 #include <sys/tty.h>
79 #include <sys/proc.h>
80 #include <sys/user.h>
81 #include <sys/conf.h>
82 #include <sys/file.h>
83 #include <sys/uio.h>
84 #include <sys/kernel.h>
85 #include <sys/syslog.h>
86 #include <sys/types.h>
87 #include <sys/device.h>
88 
89 #include <machine/intr.h>
90 #include <machine/bus.h>
91 
92 #include <dev/isa/comreg.h>
93 #include <dev/isa/comvar.h>
94 #include <dev/ic/ns16550reg.h>
95 #ifdef COM_HAYESP
96 #include <dev/ic/hayespreg.h>
97 #endif
98 #define	com_lcr	com_cfcr
99 
100 #include "com.h"
101 
102 #ifdef COM_HAYESP
103 int comprobeHAYESP __P((bus_space_handle_t hayespioh, struct com_softc *sc));
104 #endif
105 #ifdef KGDB
106 void com_kgdb_attach __P((struct com_softc *, bus_space_tag_t,
107 			  bus_space_handle_t));
108 #endif
109 void	com_attach_subr	__P((struct com_softc *sc));
110 void	comdiag		__P((void *));
111 int	comspeed	__P((long));
112 int	comparam	__P((struct tty *, struct termios *));
113 void	comstart	__P((struct tty *));
114 void	comstop		__P((struct tty *, int));
115 #ifdef __GENERIC_SOFT_INTERRUPTS
116 void 	comsoft		__P((void *));
117 #else
118 #ifndef alpha
119 void 	comsoft		__P((void));
120 #else
121 void 	comsoft		__P((void *));
122 #endif
123 #endif
124 int	comhwiflow	__P((struct tty *, int));
125 
126 void	com_loadchannelregs __P((struct com_softc *));
127 void	com_hwiflow	__P((struct com_softc *, int));
128 void	com_break	__P((struct com_softc *, int));
129 void	com_modem	__P((struct com_softc *, int));
130 void	com_iflush	__P((struct com_softc *));
131 
132 /* XXX: These belong elsewhere */
133 cdev_decl(com);
134 bdev_decl(com);
135 
136 struct consdev;
137 void	comcnprobe	__P((struct consdev *));
138 void	comcninit	__P((struct consdev *));
139 int	comcngetc	__P((dev_t));
140 void	comcnputc	__P((dev_t, int));
141 void	comcnpollc	__P((dev_t, int));
142 
143 #define	integrate	static inline
144 integrate void comrxint		__P((struct com_softc *, struct tty *));
145 integrate void comtxint		__P((struct com_softc *, struct tty *));
146 integrate void commsrint	__P((struct com_softc *, struct tty *));
147 
148 struct cfdriver com_cd = {
149 	NULL, "com", DV_TTY
150 };
151 
152 void cominitcons 	__P((bus_space_tag_t, bus_space_handle_t, int));
153 
154 #ifdef CONSPEED
155 int	comconsrate = CONSPEED;
156 #else
157 int	comconsrate = TTYDEF_SPEED;
158 #endif
159 int	comconsaddr;
160 int	comconsattached;
161 bus_space_tag_t comconstag;
162 bus_space_handle_t comconsioh;
163 tcflag_t comconscflag = TTYDEF_CFLAG;
164 
165 int	commajor;
166 
167 #ifndef __GENERIC_SOFT_INTERRUPTS
168 #ifdef alpha
169 volatile int	com_softintr_scheduled;
170 #endif
171 #endif
172 
173 #ifdef KGDB
174 #include <machine/remote-sl.h>
175 extern int kgdb_dev;
176 extern int kgdb_rate;
177 extern int kgdb_debug_init;
178 #endif
179 
180 #define	COMUNIT(x)	(minor(x))
181 
182 int
183 comspeed(speed)
184 	long speed;
185 {
186 #define	divrnd(n, q)	(((n)*2/(q)+1)/2)	/* divide and round off */
187 
188 	int x, err;
189 
190 #if 0
191 	if (speed == 0)
192 		return (0);
193 #endif
194 	if (speed <= 0)
195 		return (-1);
196 	x = divrnd((COM_FREQ / 16), speed);
197 	if (x <= 0)
198 		return (-1);
199 	err = divrnd((COM_FREQ / 16) * 1000, speed * x) - 1000;
200 	if (err < 0)
201 		err = -err;
202 	if (err > COM_TOLERANCE)
203 		return (-1);
204 	return (x);
205 
206 #undef	divrnd(n, q)
207 }
208 
209 #ifdef COM_DEBUG
210 void comstatus __P((struct com_softc *, char *));
211 void
212 comstatus(sc, str)
213 	struct com_softc *sc;
214 	char *str;
215 {
216 	struct tty *tp = sc->sc_tty;
217 
218 	printf("%s: %s %sclocal  %sdcd %sts_carr_on %sdtr %stx_stopped\n",
219 	    sc->sc_dev.dv_xname, str,
220 	    ISSET(tp->t_cflag, CLOCAL) ? "+" : "-",
221 	    ISSET(sc->sc_msr, MSR_DCD) ? "+" : "-",
222 	    ISSET(tp->t_state, TS_CARR_ON) ? "+" : "-",
223 	    ISSET(sc->sc_mcr, MCR_DTR) ? "+" : "-",
224 	    sc->sc_tx_stopped ? "+" : "-");
225 
226 	printf("%s: %s %scrtscts %scts %sts_ttstop  %srts %srx_blocked\n",
227 	    sc->sc_dev.dv_xname, str,
228 	    ISSET(tp->t_cflag, CRTSCTS) ? "+" : "-",
229 	    ISSET(sc->sc_msr, MSR_CTS) ? "+" : "-",
230 	    ISSET(tp->t_state, TS_TTSTOP) ? "+" : "-",
231 	    ISSET(sc->sc_mcr, MCR_RTS) ? "+" : "-",
232 	    sc->sc_rx_blocked ? "+" : "-");
233 }
234 #endif
235 
236 int
237 comprobe1(iot, ioh, iobase)
238 	bus_space_tag_t iot;
239 	bus_space_handle_t ioh;
240 	int iobase;
241 {
242 
243 	/* force access to id reg */
244 	bus_space_write_1(iot, ioh, com_lcr, 0);
245 	bus_space_write_1(iot, ioh, com_iir, 0);
246 	if (bus_space_read_1(iot, ioh, com_iir) & 0x38)
247 		return (0);
248 
249 	return (1);
250 }
251 
252 #ifdef COM_HAYESP
253 int
254 comprobeHAYESP(hayespioh, sc)
255 	bus_space_handle_t hayespioh;
256 	struct com_softc *sc;
257 {
258 	char	val, dips;
259 	int	combaselist[] = { 0x3f8, 0x2f8, 0x3e8, 0x2e8 };
260 	bus_space_tag_t iot = sc->sc_iot;
261 
262 	/*
263 	 * Hayes ESP cards have two iobases.  One is for compatibility with
264 	 * 16550 serial chips, and at the same ISA PC base addresses.  The
265 	 * other is for ESP-specific enhanced features, and lies at a
266 	 * different addressing range entirely (0x140, 0x180, 0x280, or 0x300).
267 	 */
268 
269 	/* Test for ESP signature */
270 	if ((bus_space_read_1(iot, hayespioh, 0) & 0xf3) == 0)
271 		return (0);
272 
273 	/*
274 	 * ESP is present at ESP enhanced base address; unknown com port
275 	 */
276 
277 	/* Get the dip-switch configurations */
278 	bus_space_write_1(iot, hayespioh, HAYESP_CMD1, HAYESP_GETDIPS);
279 	dips = bus_space_read_1(iot, hayespioh, HAYESP_STATUS1);
280 
281 	/* Determine which com port this ESP card services: bits 0,1 of  */
282 	/*  dips is the port # (0-3); combaselist[val] is the com_iobase */
283 	if (sc->sc_iobase != combaselist[dips & 0x03])
284 		return (0);
285 
286 	printf(": ESP");
287 
288  	/* Check ESP Self Test bits. */
289 	/* Check for ESP version 2.0: bits 4,5,6 == 010 */
290 	bus_space_write_1(iot, hayespioh, HAYESP_CMD1, HAYESP_GETTEST);
291 	val = bus_space_read_1(iot, hayespioh, HAYESP_STATUS1); /* Clear reg1 */
292 	val = bus_space_read_1(iot, hayespioh, HAYESP_STATUS2);
293 	if ((val & 0x70) < 0x20) {
294 		printf("-old (%o)", val & 0x70);
295 		/* we do not support the necessary features */
296 		return (0);
297 	}
298 
299 	/* Check for ability to emulate 16550: bit 8 == 1 */
300 	if ((dips & 0x80) == 0) {
301 		printf(" slave");
302 		/* XXX Does slave really mean no 16550 support?? */
303 		return (0);
304 	}
305 
306 	/*
307 	 * If we made it this far, we are a full-featured ESP v2.0 (or
308 	 * better), at the correct com port address.
309 	 */
310 
311 	SET(sc->sc_hwflags, COM_HW_HAYESP);
312 	printf(", 1024 byte fifo\n");
313 	return (1);
314 }
315 #endif
316 
317 #ifdef KGDB
318 void
319 com_kgdb_attach(sc, iot, ioh)
320 	struct com_softc *sc;
321 	bus_space_tag_t iot;
322 	bus_space_handle_t ioh;
323 {
324 
325 	if (kgdb_dev == makedev(commajor, unit)) {
326 		if (ISSET(sc->sc_hwflags, COM_HW_CONSOLE))
327 			kgdb_dev = -1;	/* can't debug over console port */
328 		else {
329 			cominitcons(iot, ioh, kgdb_rate);
330 			if (kgdb_debug_init) {
331 				/*
332 				 * Print prefix of device name,
333 				 * let kgdb_connect print the rest.
334 				 */
335 				printf("%s: ", sc->sc_dev.dv_xname);
336 				kgdb_connect(1);
337 			} else
338 				printf("%s: kgdb enabled\n",
339 				    sc->sc_dev.dv_xname);
340 		}
341 	}
342 }
343 #endif
344 
345 
346 void
347 com_attach_subr(sc)
348 	struct com_softc *sc;
349 {
350 	int iobase = sc->sc_iobase;
351 	bus_space_tag_t iot = sc->sc_iot;
352 	bus_space_handle_t ioh = sc->sc_ioh;
353 #ifdef COM_HAYESP
354 	int	hayesp_ports[] = { 0x140, 0x180, 0x280, 0x300, 0 };
355 	int	*hayespp;
356 #endif
357 
358 	if (iobase == comconsaddr) {
359 		comconsattached = 1;
360 
361 		/* Make sure the console is always "hardwired". */
362 		delay(1000);			/* wait for output to finish */
363 		SET(sc->sc_hwflags, COM_HW_CONSOLE);
364 		SET(sc->sc_swflags, TIOCFLAG_SOFTCAR);
365 	}
366 
367 #ifdef COM_HAYESP
368 	/* Look for a Hayes ESP board. */
369 	for (hayespp = hayesp_ports; *hayespp != 0; hayespp++) {
370 		bus_space_handle_t hayespioh;
371 
372 #define	HAYESP_NPORTS	8			/* XXX XXX XXX ??? ??? ??? */
373 		if (bus_space_map(iot, *hayespp, HAYESP_NPORTS, 0, &hayespioh))
374 			continue;
375 		if (comprobeHAYESP(hayespioh, sc)) {
376 			sc->sc_hayespioh = hayespioh;
377 			sc->sc_fifolen = 1024;
378 
379 			/* Set 16550 compatibility mode */
380 			bus_space_write_1(iot, hayespioh, HAYESP_CMD1, HAYESP_SETMODE);
381 			bus_space_write_1(iot, hayespioh, HAYESP_CMD2,
382 			     HAYESP_MODE_FIFO|HAYESP_MODE_RTS|
383 			     HAYESP_MODE_SCALE);
384 
385 			/* Set RTS/CTS flow control */
386 			bus_space_write_1(iot, hayespioh, HAYESP_CMD1, HAYESP_SETFLOWTYPE);
387 			bus_space_write_1(iot, hayespioh, HAYESP_CMD2, HAYESP_FLOW_RTS);
388 			bus_space_write_1(iot, hayespioh, HAYESP_CMD2, HAYESP_FLOW_CTS);
389 
390 			/* Set flow control levels */
391 			bus_space_write_1(iot, hayespioh, HAYESP_CMD1, HAYESP_SETRXFLOW);
392 			bus_space_write_1(iot, hayespioh, HAYESP_CMD2,
393 			     HAYESP_HIBYTE(HAYESP_RXHIWMARK));
394 			bus_space_write_1(iot, hayespioh, HAYESP_CMD2,
395 			     HAYESP_LOBYTE(HAYESP_RXHIWMARK));
396 			bus_space_write_1(iot, hayespioh, HAYESP_CMD2,
397 			     HAYESP_HIBYTE(HAYESP_RXLOWMARK));
398 			bus_space_write_1(iot, hayespioh, HAYESP_CMD2,
399 			     HAYESP_LOBYTE(HAYESP_RXLOWMARK));
400 
401 			break;
402 		}
403 		bus_space_unmap(iot, hayespioh, HAYESP_NPORTS);
404 	}
405 	/* No ESP; look for other things. */
406 	if (*hayespp == 0) {
407 #endif
408 
409 	sc->sc_fifolen = 1;
410 	/* look for a NS 16550AF UART with FIFOs */
411 	bus_space_write_1(iot, ioh, com_fifo,
412 	    FIFO_ENABLE | FIFO_RCV_RST | FIFO_XMT_RST | FIFO_TRIGGER_14);
413 	delay(100);
414 	if (ISSET(bus_space_read_1(iot, ioh, com_iir), IIR_FIFO_MASK)
415 	    == IIR_FIFO_MASK)
416 		if (ISSET(bus_space_read_1(iot, ioh, com_fifo), FIFO_TRIGGER_14)
417 		    == FIFO_TRIGGER_14) {
418 			SET(sc->sc_hwflags, COM_HW_FIFO);
419 			printf(": ns16550a, working fifo\n");
420 			sc->sc_fifolen = 16;
421 		} else
422 			printf(": ns16550, broken fifo\n");
423 	else
424 		printf(": ns8250 or ns16450, no fifo\n");
425 	bus_space_write_1(iot, ioh, com_fifo, 0);
426 #ifdef COM_HAYESP
427 	}
428 #endif
429 
430 	if (!ISSET(sc->sc_hwflags, COM_HW_NOIEN))
431 		SET(sc->sc_mcr, MCR_IENABLE);
432 
433 	if (ISSET(sc->sc_hwflags, COM_HW_CONSOLE)) {
434 		cominit(iot, ioh, comconsrate);
435 		printf("%s: console\n", sc->sc_dev.dv_xname);
436 	}
437 
438 #ifdef KGDB
439 	com_kgdb_attach(sc, iot, ioh);
440 #endif
441 
442 #ifdef __GENERIC_SOFT_INTERRUPTS
443 	sc->sc_si = softintr_establish(IPL_SOFTSERIAL, comsoft, sc);
444 #endif
445 }
446 
447 int
448 comopen(dev, flag, mode, p)
449 	dev_t dev;
450 	int flag, mode;
451 	struct proc *p;
452 {
453 	int unit = COMUNIT(dev);
454 	struct com_softc *sc;
455 	struct tty *tp;
456 	int s, s2;
457 	int error = 0;
458 
459 	if (unit >= com_cd.cd_ndevs)
460 		return (ENXIO);
461 	sc = com_cd.cd_devs[unit];
462 	if (!sc)
463 		return (ENXIO);
464 
465 	if (!sc->sc_tty) {
466 		tp = sc->sc_tty = ttymalloc();
467 		tty_attach(tp);
468 	} else
469 		tp = sc->sc_tty;
470 
471 	if (ISSET(tp->t_state, TS_ISOPEN) &&
472 	    ISSET(tp->t_state, TS_XCLUDE) &&
473 	    p->p_ucred->cr_uid != 0)
474 		return (EBUSY);
475 
476 	s = spltty();
477 
478 	/* We need to set this early for the benefit of comsoft(). */
479 	SET(tp->t_state, TS_WOPEN);
480 
481 	/*
482 	 * Do the following iff this is a first open.
483 	 */
484 	if (!ISSET(tp->t_state, TS_ISOPEN)) {
485 		struct termios t;
486 
487 		/* Turn on interrupts. */
488 		sc->sc_ier = IER_ERXRDY | IER_ERLS | IER_EMSC;
489 		bus_space_write_1(sc->sc_iot, sc->sc_ioh, com_ier, sc->sc_ier);
490 
491 		/* Fetch the current modem control status, needed later. */
492 		sc->sc_msr = bus_space_read_1(sc->sc_iot, sc->sc_ioh, com_msr);
493 
494 		/* Add some entry points needed by the tty layer. */
495 		tp->t_oproc = comstart;
496 		tp->t_param = comparam;
497 		tp->t_hwiflow = comhwiflow;
498 		tp->t_dev = dev;
499 
500 		/*
501 		 * Initialize the termios status to the defaults.  Add in the
502 		 * sticky bits from TIOCSFLAGS.
503 		 */
504 		t.c_ispeed = 0;
505 		if (ISSET(sc->sc_hwflags, COM_HW_CONSOLE)) {
506 			t.c_ospeed = comconsrate;
507 			t.c_cflag = comconscflag;
508 		} else {
509 			t.c_ospeed = TTYDEF_SPEED;
510 			t.c_cflag = TTYDEF_CFLAG;
511 		}
512 		if (ISSET(sc->sc_swflags, TIOCFLAG_CLOCAL))
513 			SET(t.c_cflag, CLOCAL);
514 		if (ISSET(sc->sc_swflags, TIOCFLAG_CRTSCTS))
515 			SET(t.c_cflag, CRTSCTS);
516 		if (ISSET(sc->sc_swflags, TIOCFLAG_MDMBUF))
517 			SET(t.c_cflag, MDMBUF);
518 		tp->t_iflag = TTYDEF_IFLAG;
519 		tp->t_oflag = TTYDEF_OFLAG;
520 		tp->t_lflag = TTYDEF_LFLAG;
521 		ttychars(tp);
522 		(void) comparam(tp, &t);
523 		ttsetwater(tp);
524 
525 		s2 = splserial();
526 
527 		/*
528 		 * Turn on DTR.  We must always do this, even if carrier is not
529 		 * present, because otherwise we'd have to use TIOCSDTR
530 		 * immediately after setting CLOCAL.  We will drop DTR only on
531 		 * the next high-low transition of DCD, or by explicit request.
532 		 */
533 		com_modem(sc, 1);
534 
535 		/* Clear the input ring, and unblock. */
536 		sc->sc_rbput = sc->sc_rbget = 0;
537 		sc->sc_rbavail = RXBUFSIZE;
538 		com_iflush(sc);
539 		sc->sc_rx_blocked = 0;
540 		com_hwiflow(sc, 0);
541 
542 #ifdef COM_DEBUG
543 		comstatus(sc, "comopen  ");
544 #endif
545 
546 		splx(s2);
547 	}
548 	error = 0;
549 
550 	/* If we're doing a blocking open... */
551 	if (!ISSET(flag, O_NONBLOCK))
552 		/* ...then wait for carrier. */
553 		while (!ISSET(tp->t_state, TS_CARR_ON) &&
554 		    !ISSET(tp->t_cflag, CLOCAL | MDMBUF)) {
555 			error = ttysleep(tp, &tp->t_rawq, TTIPRI | PCATCH,
556 			    ttopen, 0);
557 			if (error) {
558 				/*
559 				 * If the open was interrupted and nobody
560 				 * else has the device open, then hang up.
561 				 */
562 				if (!ISSET(tp->t_state, TS_ISOPEN)) {
563 					com_modem(sc, 0);
564 					CLR(tp->t_state, TS_WOPEN);
565 					ttwakeup(tp);
566 				}
567 				break;
568 			}
569 			SET(tp->t_state, TS_WOPEN);
570 		}
571 
572 	splx(s);
573 	if (error == 0)
574 		error = (*linesw[tp->t_line].l_open)(dev, tp);
575 	return (error);
576 }
577 
578 int
579 comclose(dev, flag, mode, p)
580 	dev_t dev;
581 	int flag, mode;
582 	struct proc *p;
583 {
584 	int unit = COMUNIT(dev);
585 	struct com_softc *sc = com_cd.cd_devs[unit];
586 	struct tty *tp = sc->sc_tty;
587 	int s;
588 
589 	/* XXX This is for cons.c. */
590 	if (!ISSET(tp->t_state, TS_ISOPEN))
591 		return (0);
592 
593 	(*linesw[tp->t_line].l_close)(tp, flag);
594 	ttyclose(tp);
595 
596 	/* If we were asserting flow control, then deassert it. */
597 	sc->sc_rx_blocked = 1;
598 	com_hwiflow(sc, 1);
599 	/* Clear any break condition set with TIOCSBRK. */
600 	com_break(sc, 0);
601 	/*
602 	 * Hang up if necessary.  Wait a bit, so the other side has time to
603 	 * notice even if we immediately open the port again.
604 	 */
605 	if (ISSET(tp->t_cflag, HUPCL)) {
606 		com_modem(sc, 0);
607 		(void) tsleep(sc, TTIPRI, ttclos, hz);
608 	}
609 
610 	s = splserial();
611 	/* Turn off interrupts. */
612 	sc->sc_ier = 0;
613 	bus_space_write_1(sc->sc_iot, sc->sc_ioh, com_ier, sc->sc_ier);
614 	splx(s);
615 
616 	return (0);
617 }
618 
619 int
620 comread(dev, uio, flag)
621 	dev_t dev;
622 	struct uio *uio;
623 	int flag;
624 {
625 	struct com_softc *sc = com_cd.cd_devs[COMUNIT(dev)];
626 	struct tty *tp = sc->sc_tty;
627 
628 	return ((*linesw[tp->t_line].l_read)(tp, uio, flag));
629 }
630 
631 int
632 comwrite(dev, uio, flag)
633 	dev_t dev;
634 	struct uio *uio;
635 	int flag;
636 {
637 	struct com_softc *sc = com_cd.cd_devs[COMUNIT(dev)];
638 	struct tty *tp = sc->sc_tty;
639 
640 	return ((*linesw[tp->t_line].l_write)(tp, uio, flag));
641 }
642 
643 struct tty *
644 comtty(dev)
645 	dev_t dev;
646 {
647 	struct com_softc *sc = com_cd.cd_devs[COMUNIT(dev)];
648 	struct tty *tp = sc->sc_tty;
649 
650 	return (tp);
651 }
652 
653 int
654 comioctl(dev, cmd, data, flag, p)
655 	dev_t dev;
656 	u_long cmd;
657 	caddr_t data;
658 	int flag;
659 	struct proc *p;
660 {
661 	int unit = COMUNIT(dev);
662 	struct com_softc *sc = com_cd.cd_devs[unit];
663 	struct tty *tp = sc->sc_tty;
664 	int error;
665 
666 	error = (*linesw[tp->t_line].l_ioctl)(tp, cmd, data, flag, p);
667 	if (error >= 0)
668 		return (error);
669 
670 	error = ttioctl(tp, cmd, data, flag, p);
671 	if (error >= 0)
672 		return (error);
673 
674 	switch (cmd) {
675 	case TIOCSBRK:
676 		com_break(sc, 1);
677 		break;
678 
679 	case TIOCCBRK:
680 		com_break(sc, 0);
681 		break;
682 
683 	case TIOCSDTR:
684 		com_modem(sc, 1);
685 		break;
686 
687 	case TIOCCDTR:
688 		com_modem(sc, 0);
689 		break;
690 
691 	case TIOCGFLAGS:
692 		*(int *)data = sc->sc_swflags;
693 		break;
694 
695 	case TIOCSFLAGS:
696 		error = suser(p->p_ucred, &p->p_acflag);
697 		if (error)
698 			return (error);
699 		sc->sc_swflags = *(int *)data;
700 		break;
701 
702 	case TIOCMSET:
703 	case TIOCMBIS:
704 	case TIOCMBIC:
705 	case TIOCMGET:
706 	default:
707 		return (ENOTTY);
708 	}
709 
710 #ifdef COM_DEBUG
711 		comstatus(sc, "comioctl ");
712 #endif
713 
714 	return (0);
715 }
716 
717 void
718 com_break(sc, onoff)
719 	struct com_softc *sc;
720 	int onoff;
721 {
722 	int s;
723 
724 	s = splserial();
725 	if (onoff)
726 		SET(sc->sc_lcr, LCR_SBREAK);
727 	else
728 		CLR(sc->sc_lcr, LCR_SBREAK);
729 
730 	if (!sc->sc_heldchange) {
731 		if (sc->sc_tx_busy) {
732 			sc->sc_heldtbc = sc->sc_tbc;
733 			sc->sc_tbc = 0;
734 			sc->sc_heldchange = 1;
735 		} else
736 			com_loadchannelregs(sc);
737 	}
738 	splx(s);
739 }
740 
741 void
742 com_modem(sc, onoff)
743 	struct com_softc *sc;
744 	int onoff;
745 {
746 	int s;
747 
748 	s = splserial();
749 	if (onoff)
750 		SET(sc->sc_mcr, sc->sc_mcr_dtr);
751 	else
752 		CLR(sc->sc_mcr, sc->sc_mcr_dtr);
753 
754 	if (!sc->sc_heldchange) {
755 		if (sc->sc_tx_busy) {
756 			sc->sc_heldtbc = sc->sc_tbc;
757 			sc->sc_tbc = 0;
758 			sc->sc_heldchange = 1;
759 		} else
760 			com_loadchannelregs(sc);
761 	}
762 	splx(s);
763 }
764 
765 int
766 comparam(tp, t)
767 	struct tty *tp;
768 	struct termios *t;
769 {
770 	struct com_softc *sc = com_cd.cd_devs[COMUNIT(tp->t_dev)];
771 	int ospeed = comspeed(t->c_ospeed);
772 	u_char lcr;
773 	int s;
774 
775 	/* check requested parameters */
776 	if (ospeed < 0)
777 		return (EINVAL);
778 	if (t->c_ispeed && t->c_ispeed != t->c_ospeed)
779 		return (EINVAL);
780 
781 	lcr = ISSET(sc->sc_lcr, LCR_SBREAK);
782 
783 	switch (ISSET(t->c_cflag, CSIZE)) {
784 	case CS5:
785 		SET(lcr, LCR_5BITS);
786 		break;
787 	case CS6:
788 		SET(lcr, LCR_6BITS);
789 		break;
790 	case CS7:
791 		SET(lcr, LCR_7BITS);
792 		break;
793 	case CS8:
794 		SET(lcr, LCR_8BITS);
795 		break;
796 	}
797 	if (ISSET(t->c_cflag, PARENB)) {
798 		SET(lcr, LCR_PENAB);
799 		if (!ISSET(t->c_cflag, PARODD))
800 			SET(lcr, LCR_PEVEN);
801 	}
802 	if (ISSET(t->c_cflag, CSTOPB))
803 		SET(lcr, LCR_STOPB);
804 
805 	s = splserial();
806 
807 	sc->sc_lcr = lcr;
808 
809 	/*
810 	 * For the console, always force CLOCAL and !HUPCL, so that the port
811 	 * is always active.
812 	 */
813 	if (ISSET(sc->sc_swflags, TIOCFLAG_SOFTCAR) ||
814 	    ISSET(sc->sc_hwflags, COM_HW_CONSOLE)) {
815 		SET(t->c_cflag, CLOCAL);
816 		CLR(t->c_cflag, HUPCL);
817 	}
818 
819 	/*
820 	 * If we're not in a mode that assumes a connection is present, then
821 	 * ignore carrier changes.
822 	 */
823 	if (ISSET(t->c_cflag, CLOCAL | MDMBUF))
824 		sc->sc_msr_dcd = 0;
825 	else
826 		sc->sc_msr_dcd = MSR_DCD;
827 	/*
828 	 * Set the flow control pins depending on the current flow control
829 	 * mode.
830 	 */
831 	if (ISSET(t->c_cflag, CRTSCTS)) {
832 		sc->sc_mcr_dtr = MCR_DTR;
833 		sc->sc_mcr_rts = MCR_RTS;
834 		sc->sc_msr_cts = MSR_CTS;
835 		sc->sc_r_hiwat = RXHIWAT;
836 	} else if (ISSET(t->c_cflag, MDMBUF)) {
837 		/*
838 		 * For DTR/DCD flow control, make sure we don't toggle DTR for
839 		 * carrier detection.
840 		 */
841 		sc->sc_mcr_dtr = 0;
842 		sc->sc_mcr_rts = MCR_DTR;
843 		sc->sc_msr_cts = MSR_DCD;
844 		sc->sc_r_hiwat = RXHIWAT;
845 	} else {
846 		/*
847 		 * If no flow control, then always set RTS.  This will make
848 		 * the other side happy if it mistakenly thinks we're doing
849 		 * RTS/CTS flow control.
850 		 */
851 		sc->sc_mcr_dtr = MCR_DTR | MCR_RTS;
852 		sc->sc_mcr_rts = 0;
853 		sc->sc_msr_cts = 0;
854 		sc->sc_r_hiwat = 0;
855 		if (ISSET(sc->sc_mcr, MCR_DTR))
856 			SET(sc->sc_mcr, MCR_RTS);
857 		else
858 			CLR(sc->sc_mcr, MCR_RTS);
859 	}
860 	sc->sc_msr_mask = sc->sc_msr_cts | sc->sc_msr_dcd;
861 
862 #if 0
863 	if (ospeed == 0)
864 		CLR(sc->sc_mcr, sc->sc_mcr_dtr);
865 	else
866 		SET(sc->sc_mcr, sc->sc_mcr_dtr);
867 #endif
868 
869 	sc->sc_dlbl = ospeed;
870 	sc->sc_dlbh = ospeed >> 8;
871 
872 	/*
873 	 * Set the FIFO threshold based on the receive speed.
874 	 *
875 	 *  * If it's a low speed, it's probably a mouse or some other
876 	 *    interactive device, so set the threshold low.
877 	 *  * If it's a high speed, trim the trigger level down to prevent
878 	 *    overflows.
879 	 *  * Otherwise set it a bit higher.
880 	 */
881 	if (ISSET(sc->sc_hwflags, COM_HW_HAYESP))
882 		sc->sc_fifo = FIFO_DMA_MODE | FIFO_ENABLE | FIFO_TRIGGER_8;
883 	else if (ISSET(sc->sc_hwflags, COM_HW_FIFO))
884 		sc->sc_fifo = FIFO_ENABLE |
885 		    (t->c_ospeed <= 1200 ? FIFO_TRIGGER_1 :
886 		     t->c_ospeed <= 38400 ? FIFO_TRIGGER_8 : FIFO_TRIGGER_4);
887 	else
888 		sc->sc_fifo = 0;
889 
890 	/* and copy to tty */
891 	tp->t_ispeed = 0;
892 	tp->t_ospeed = t->c_ospeed;
893 	tp->t_cflag = t->c_cflag;
894 
895 	if (!sc->sc_heldchange) {
896 		if (sc->sc_tx_busy) {
897 			sc->sc_heldtbc = sc->sc_tbc;
898 			sc->sc_tbc = 0;
899 			sc->sc_heldchange = 1;
900 		} else
901 			com_loadchannelregs(sc);
902 	}
903 
904 	splx(s);
905 
906 	/*
907 	 * Update the tty layer's idea of the carrier bit, in case we changed
908 	 * CLOCAL or MDMBUF.  We don't hang up here; we only do that if we
909 	 * lose carrier while carrier detection is on.
910 	 */
911 	(void) (*linesw[tp->t_line].l_modem)(tp, ISSET(sc->sc_msr, MSR_DCD));
912 
913 #ifdef COM_DEBUG
914 	comstatus(sc, "comparam ");
915 #endif
916 
917 	/* XXXXX FIX ME */
918 	/* Block or unblock as needed. */
919 	if (!ISSET(t->c_cflag, CHWFLOW)) {
920 		if (sc->sc_rx_blocked) {
921 			sc->sc_rx_blocked = 0;
922 			com_hwiflow(sc, 0);
923 		}
924 		if (sc->sc_tx_stopped) {
925 			sc->sc_tx_stopped = 0;
926 			comstart(tp);
927 		}
928 	} else {
929 #if 0
930 		commsrint(sc, tp);
931 #endif
932 	}
933 
934 	return (0);
935 }
936 
937 void
938 com_iflush(sc)
939 	struct com_softc *sc;
940 {
941 	bus_space_tag_t iot = sc->sc_iot;
942 	bus_space_handle_t ioh = sc->sc_ioh;
943 
944 	/* flush any pending I/O */
945 	while (ISSET(bus_space_read_1(iot, ioh, com_lsr), LSR_RXRDY))
946 		(void) bus_space_read_1(iot, ioh, com_data);
947 }
948 
949 void
950 com_loadchannelregs(sc)
951 	struct com_softc *sc;
952 {
953 	bus_space_tag_t iot = sc->sc_iot;
954 	bus_space_handle_t ioh = sc->sc_ioh;
955 
956 	/* XXXXX necessary? */
957 	com_iflush(sc);
958 
959 	bus_space_write_1(iot, ioh, com_ier, 0);
960 
961 	bus_space_write_1(iot, ioh, com_lcr, sc->sc_lcr | LCR_DLAB);
962 	bus_space_write_1(iot, ioh, com_dlbl, sc->sc_dlbl);
963 	bus_space_write_1(iot, ioh, com_dlbh, sc->sc_dlbh);
964 	bus_space_write_1(iot, ioh, com_lcr, sc->sc_lcr);
965 	bus_space_write_1(iot, ioh, com_mcr, sc->sc_mcr_active = sc->sc_mcr);
966 	bus_space_write_1(iot, ioh, com_fifo, sc->sc_fifo);
967 
968 	bus_space_write_1(iot, ioh, com_ier, sc->sc_ier);
969 }
970 
971 int
972 comhwiflow(tp, block)
973 	struct tty *tp;
974 	int block;
975 {
976 	struct com_softc *sc = com_cd.cd_devs[COMUNIT(tp->t_dev)];
977 	int s;
978 
979 	if (sc->sc_mcr_rts == 0)
980 		return (0);
981 
982 	s = splserial();
983 	if (block) {
984 		/*
985 		 * The tty layer is asking us to block input.
986 		 * If we already did it, just return TRUE.
987 		 */
988 		if (sc->sc_rx_blocked)
989 			goto out;
990 		sc->sc_rx_blocked = 1;
991 	} else {
992 		/*
993 		 * The tty layer is asking us to resume input.
994 		 * The input ring is always empty by now.
995 		 */
996 		sc->sc_rx_blocked = 0;
997 	}
998 	com_hwiflow(sc, block);
999 out:
1000 	splx(s);
1001 	return (1);
1002 }
1003 
1004 /*
1005  * (un)block input via hw flowcontrol
1006  */
1007 void
1008 com_hwiflow(sc, block)
1009 	struct com_softc *sc;
1010 	int block;
1011 {
1012 	bus_space_tag_t iot = sc->sc_iot;
1013 	bus_space_handle_t ioh = sc->sc_ioh;
1014 
1015 	if (sc->sc_mcr_rts == 0)
1016 		return;
1017 
1018 	if (block) {
1019 		CLR(sc->sc_mcr, sc->sc_mcr_rts);
1020 		CLR(sc->sc_mcr_active, sc->sc_mcr_rts);
1021 	} else {
1022 		SET(sc->sc_mcr, sc->sc_mcr_rts);
1023 		SET(sc->sc_mcr_active, sc->sc_mcr_rts);
1024 	}
1025 	bus_space_write_1(iot, ioh, com_mcr, sc->sc_mcr_active);
1026 }
1027 
1028 
1029 void
1030 comstart(tp)
1031 	struct tty *tp;
1032 {
1033 	struct com_softc *sc = com_cd.cd_devs[COMUNIT(tp->t_dev)];
1034 	bus_space_tag_t iot = sc->sc_iot;
1035 	bus_space_handle_t ioh = sc->sc_ioh;
1036 	int s;
1037 
1038 	s = spltty();
1039 	if (ISSET(tp->t_state, TS_BUSY))
1040 		goto out;
1041 	if (ISSET(tp->t_state, TS_TIMEOUT | TS_TTSTOP))
1042 		goto stopped;
1043 
1044 	if (sc->sc_tx_stopped)
1045 		goto stopped;
1046 
1047 	if (tp->t_outq.c_cc <= tp->t_lowat) {
1048 		if (ISSET(tp->t_state, TS_ASLEEP)) {
1049 			CLR(tp->t_state, TS_ASLEEP);
1050 			wakeup(&tp->t_outq);
1051 		}
1052 		selwakeup(&tp->t_wsel);
1053 		if (tp->t_outq.c_cc == 0)
1054 			goto stopped;
1055 	}
1056 
1057 	/* Grab the first contiguous region of buffer space. */
1058 	{
1059 		u_char *tba;
1060 		int tbc;
1061 
1062 		tba = tp->t_outq.c_cf;
1063 		tbc = ndqb(&tp->t_outq, 0);
1064 
1065 		(void)splserial();
1066 
1067 		sc->sc_tba = tba;
1068 		sc->sc_tbc = tbc;
1069 	}
1070 
1071 	SET(tp->t_state, TS_BUSY);
1072 	sc->sc_tx_busy = 1;
1073 
1074 	/* Enable transmit completion interrupts if necessary. */
1075 	if (!ISSET(sc->sc_ier, IER_ETXRDY)) {
1076 		SET(sc->sc_ier, IER_ETXRDY);
1077 		bus_space_write_1(iot, ioh, com_ier, sc->sc_ier);
1078 	}
1079 
1080 	/* Output the first chunk of the contiguous buffer. */
1081 	{
1082 		int n;
1083 
1084 		n = sc->sc_fifolen;
1085 		if (n > sc->sc_tbc)
1086 			n = sc->sc_tbc;
1087 		bus_space_write_multi_1(iot, ioh, com_data, sc->sc_tba, n);
1088 		sc->sc_tbc -= n;
1089 		sc->sc_tba += n;
1090 	}
1091 	splx(s);
1092 	return;
1093 
1094 stopped:
1095 	/* Disable transmit completion interrupts if necessary. */
1096 	if (ISSET(sc->sc_ier, IER_ETXRDY)) {
1097 		CLR(sc->sc_ier, IER_ETXRDY);
1098 		bus_space_write_1(iot, ioh, com_ier, sc->sc_ier);
1099 	}
1100 out:
1101 	splx(s);
1102 	return;
1103 }
1104 
1105 /*
1106  * Stop output on a line.
1107  */
1108 void
1109 comstop(tp, flag)
1110 	struct tty *tp;
1111 	int flag;
1112 {
1113 	struct com_softc *sc = com_cd.cd_devs[COMUNIT(tp->t_dev)];
1114 	int s;
1115 
1116 	s = splserial();
1117 	if (ISSET(tp->t_state, TS_BUSY)) {
1118 		/* Stop transmitting at the next chunk. */
1119 		sc->sc_tbc = 0;
1120 		sc->sc_heldtbc = 0;
1121 		if (!ISSET(tp->t_state, TS_TTSTOP))
1122 			SET(tp->t_state, TS_FLUSH);
1123 	}
1124 	splx(s);
1125 }
1126 
1127 void
1128 comdiag(arg)
1129 	void *arg;
1130 {
1131 	struct com_softc *sc = arg;
1132 	int overflows, floods;
1133 	int s;
1134 
1135 	s = splserial();
1136 	overflows = sc->sc_overflows;
1137 	sc->sc_overflows = 0;
1138 	floods = sc->sc_floods;
1139 	sc->sc_floods = 0;
1140 	sc->sc_errors = 0;
1141 	splx(s);
1142 
1143 	log(LOG_WARNING,
1144 	    "%s: %d silo overflow%s, %d ibuf flood%s\n",
1145 	    sc->sc_dev.dv_xname,
1146 	    overflows, overflows == 1 ? "" : "s",
1147 	    floods, floods == 1 ? "" : "s");
1148 }
1149 
1150 integrate void
1151 comrxint(sc, tp)
1152 	struct com_softc	*sc;
1153 	struct tty	*tp;
1154 {
1155 	u_int	get, cc, scc;
1156 	int	code;
1157 	u_char	lsr;
1158 	int	s;
1159 	static int lsrmap[8] = {
1160 		0,      TTY_PE,
1161 		TTY_FE, TTY_PE|TTY_FE,
1162 		TTY_FE, TTY_PE|TTY_FE,
1163 		TTY_FE, TTY_PE|TTY_FE
1164 	};
1165 
1166 	get = sc->sc_rbget;
1167 	scc = cc = RXBUFSIZE - sc->sc_rbavail;
1168 
1169 	if (cc == RXBUFSIZE) {
1170 		sc->sc_floods++;
1171 		if (sc->sc_errors++ == 0)
1172 			timeout(comdiag, sc, 60 * hz);
1173 	}
1174 
1175 	while (cc--) {
1176 		lsr = sc->sc_lbuf[get];
1177 		if (ISSET(lsr, LSR_BI)) {
1178 #ifdef DDB
1179 			if (ISSET(sc->sc_hwflags, COM_HW_CONSOLE))
1180 				Debugger();
1181 #endif
1182 		}
1183 		else if (ISSET(lsr, LSR_OE)) {
1184 			sc->sc_overflows++;
1185 			if (sc->sc_errors++ == 0)
1186 				timeout(comdiag, sc, 60 * hz);
1187 		}
1188 		code = sc->sc_rbuf[get] |
1189 		    lsrmap[(lsr & (LSR_BI|LSR_FE|LSR_PE)) >> 2];
1190 		(*linesw[tp->t_line].l_rint)(code, tp);
1191 		get = (get + 1) & RXBUFMASK;
1192 	}
1193 
1194 	sc->sc_rbget = get;
1195 	s = splserial();
1196 	sc->sc_rbavail += scc;
1197 	/*
1198 	 * Buffers should be ok again, release possible block, but only if the
1199 	 * tty layer isn't blocking too.
1200 	 */
1201 	if (sc->sc_rx_blocked && !ISSET(tp->t_state, TS_TBLOCK)) {
1202 		sc->sc_rx_blocked = 0;
1203 		com_hwiflow(sc, 0);
1204 	}
1205 	splx(s);
1206 }
1207 
1208 integrate void
1209 comtxint(sc, tp)
1210 	struct com_softc	*sc;
1211 	struct tty	*tp;
1212 {
1213 
1214 	CLR(tp->t_state, TS_BUSY);
1215 	if (ISSET(tp->t_state, TS_FLUSH))
1216 		CLR(tp->t_state, TS_FLUSH);
1217 	else
1218 		ndflush(&tp->t_outq, (int)(sc->sc_tba - tp->t_outq.c_cf));
1219 	(*linesw[tp->t_line].l_start)(tp);
1220 }
1221 
1222 integrate void
1223 commsrint(sc, tp)
1224 	struct com_softc	*sc;
1225 	struct tty	*tp;
1226 {
1227 	u_char msr, delta;
1228 	int s;
1229 
1230 	s = splserial();
1231 	msr = sc->sc_msr;
1232 	delta = sc->sc_msr_delta;
1233 	sc->sc_msr_delta = 0;
1234 	splx(s);
1235 
1236 	if (ISSET(delta, sc->sc_msr_dcd)) {
1237 		/*
1238 		 * Inform the tty layer that carrier detect changed.
1239 		 */
1240 		(void) (*linesw[tp->t_line].l_modem)(tp, ISSET(msr, MSR_DCD));
1241 	}
1242 
1243 	if (ISSET(delta, sc->sc_msr_cts)) {
1244 		/* Block or unblock output according to flow control. */
1245 		if (ISSET(msr, sc->sc_msr_cts)) {
1246 			sc->sc_tx_stopped = 0;
1247 			(*linesw[tp->t_line].l_start)(tp);
1248 		} else {
1249 			sc->sc_tx_stopped = 1;
1250 			comstop(tp, 0);
1251 		}
1252 	}
1253 
1254 #ifdef COM_DEBUG
1255 	comstatus(sc, "commsrint");
1256 #endif
1257 }
1258 
1259 #ifdef __GENERIC_SOFT_INTERRUPTS
1260 void
1261 comsoft(arg)
1262 	void *arg;
1263 {
1264 	struct com_softc *sc = arg;
1265 	struct tty *tp;
1266 
1267 	{
1268 #else
1269 void
1270 #ifndef alpha
1271 comsoft()
1272 #else
1273 comsoft(arg)
1274 	void *arg;
1275 #endif
1276 {
1277 	struct com_softc	*sc;
1278 	struct tty	*tp;
1279 	int	unit;
1280 #ifdef alpha
1281 	int s;
1282 
1283 	s = splsoftserial();
1284 	com_softintr_scheduled = 0;
1285 #endif
1286 
1287 	for (unit = 0; unit < com_cd.cd_ndevs; unit++) {
1288 		sc = com_cd.cd_devs[unit];
1289 		if (sc == NULL)
1290 			continue;
1291 #endif
1292 
1293 		tp = sc->sc_tty;
1294 		if (tp == NULL || !ISSET(tp->t_state, TS_ISOPEN | TS_WOPEN))
1295 			continue;
1296 
1297 		if (sc->sc_rx_ready) {
1298 			sc->sc_rx_ready = 0;
1299 			comrxint(sc, tp);
1300 		}
1301 
1302 		if (sc->sc_st_check) {
1303 			sc->sc_st_check = 0;
1304 			commsrint(sc, tp);
1305 		}
1306 
1307 		if (sc->sc_tx_done) {
1308 			sc->sc_tx_done = 0;
1309 			comtxint(sc, tp);
1310 		}
1311 	}
1312 
1313 #ifndef __GENERIC_SOFT_INTERRUPTS
1314 #ifdef alpha
1315 	splx(s);
1316 #endif
1317 #endif
1318 }
1319 
1320 int
1321 comintr(arg)
1322 	void	*arg;
1323 {
1324 	struct com_softc *sc = arg;
1325 	bus_space_tag_t iot = sc->sc_iot;
1326 	bus_space_handle_t ioh = sc->sc_ioh;
1327 	u_char	lsr, iir;
1328 	u_int	put, cc;
1329 
1330 	iir = bus_space_read_1(iot, ioh, com_iir);
1331 	if (ISSET(iir, IIR_NOPEND))
1332 		return (0);
1333 
1334 	put = sc->sc_rbput;
1335 	cc = sc->sc_rbavail;
1336 
1337 	do {
1338 		u_char	msr, delta;
1339 
1340 		lsr = bus_space_read_1(iot, ioh, com_lsr);
1341 		if (ISSET(lsr, LSR_RCV_MASK)) {
1342 			for (; ISSET(lsr, LSR_RCV_MASK) && cc > 0; cc--) {
1343 				sc->sc_rbuf[put] =
1344 				    bus_space_read_1(iot, ioh, com_data);
1345 				sc->sc_lbuf[put] = lsr;
1346 				put = (put + 1) & RXBUFMASK;
1347 				lsr = bus_space_read_1(iot, ioh, com_lsr);
1348 			}
1349 			/*
1350 			 * Current string of incoming characters ended because
1351 			 * no more data was available. Schedule a receive event
1352 			 * if any data was received. Drop any characters that
1353 			 * we couldn't handle.
1354 			 */
1355 			sc->sc_rbput = put;
1356 			sc->sc_rbavail = cc;
1357 			sc->sc_rx_ready = 1;
1358 			/*
1359 			 * See if we are in danger of overflowing a buffer. If
1360 			 * so, use hardware flow control to ease the pressure.
1361 			 */
1362 			if (sc->sc_rx_blocked == 0 &&
1363 			    cc < sc->sc_r_hiwat) {
1364 				sc->sc_rx_blocked = 1;
1365 				com_hwiflow(sc, 1);
1366 			}
1367 			/*
1368 			 * If we're out of space, throw away any further input.
1369 			 */
1370 			if (!cc) {
1371 				while (ISSET(lsr, LSR_RCV_MASK)) {
1372 					bus_space_read_1(iot, ioh, com_data);
1373 					lsr = bus_space_read_1(iot, ioh,
1374 								com_lsr);
1375 				}
1376 			}
1377 		} else {
1378 			if ((iir & IIR_IMASK) == IIR_RXRDY) {
1379 				bus_space_write_1(iot, ioh, com_ier, 0);
1380 				delay(10);
1381 				bus_space_write_1(iot, ioh, com_ier,sc->sc_ier);
1382 				iir = IIR_NOPEND;
1383 				continue;
1384 			}
1385 		}
1386 
1387 		msr = bus_space_read_1(iot, ioh, com_msr);
1388 		delta = msr ^ sc->sc_msr;
1389 		sc->sc_msr = msr;
1390 		if (ISSET(delta, sc->sc_msr_mask)) {
1391 			sc->sc_msr_delta |= delta;
1392 
1393 			/*
1394 			 * Stop output immediately if we lose the output
1395 			 * flow control signal or carrier detect.
1396 			 */
1397 			if (ISSET(~msr, sc->sc_msr_mask)) {
1398 				sc->sc_tbc = 0;
1399 				sc->sc_heldtbc = 0;
1400 #ifdef COM_DEBUG
1401 				comstatus(sc, "comintr  ");
1402 #endif
1403 			}
1404 
1405 			sc->sc_st_check = 1;
1406 		}
1407 	} while (!ISSET((iir = bus_space_read_1(iot, ioh, com_iir)), IIR_NOPEND));
1408 
1409 	/*
1410 	 * Done handling any receive interrupts. See if data can be
1411 	 * transmitted as well. Schedule tx done event if no data left
1412 	 * and tty was marked busy.
1413 	 */
1414 	if (ISSET(lsr, LSR_TXRDY)) {
1415 		/*
1416 		 * If we've delayed a parameter change, do it now, and restart
1417 		 * output.
1418 		 */
1419 		if (sc->sc_heldchange) {
1420 			com_loadchannelregs(sc);
1421 			sc->sc_heldchange = 0;
1422 			sc->sc_tbc = sc->sc_heldtbc;
1423 			sc->sc_heldtbc = 0;
1424 		}
1425 		/* Output the next chunk of the contiguous buffer, if any. */
1426 		if (sc->sc_tbc > 0) {
1427 			int n;
1428 
1429 			n = sc->sc_fifolen;
1430 			if (n > sc->sc_tbc)
1431 				n = sc->sc_tbc;
1432 			bus_space_write_multi_1(iot, ioh, com_data, sc->sc_tba, n);
1433 			sc->sc_tbc -= n;
1434 			sc->sc_tba += n;
1435 		} else if (sc->sc_tx_busy) {
1436 			sc->sc_tx_busy = 0;
1437 			sc->sc_tx_done = 1;
1438 		}
1439 	}
1440 
1441 	/* Wake up the poller. */
1442 #ifdef __GENERIC_SOFT_INTERRUPTS
1443 	softintr_schedule(sc->sc_si);
1444 #else
1445 #ifndef alpha
1446 	setsoftserial();
1447 #else
1448 	if (!com_softintr_scheduled) {
1449 		com_softintr_scheduled = 1;
1450 		timeout(comsoft, NULL, 1);
1451 	}
1452 #endif
1453 #endif
1454 	return (1);
1455 }
1456 
1457 /*
1458  * Following are all routines needed for COM to act as console
1459  */
1460 #include <dev/cons.h>
1461 
1462 void
1463 comcnprobe(cp)
1464 	struct consdev *cp;
1465 {
1466 	/* XXX NEEDS TO BE FIXED XXX */
1467 	bus_space_tag_t iot = 0;
1468 	bus_space_handle_t ioh;
1469 	int found;
1470 
1471 	if (bus_space_map(iot, CONADDR, COM_NPORTS, 0, &ioh)) {
1472 		cp->cn_pri = CN_DEAD;
1473 		return;
1474 	}
1475 	found = comprobe1(iot, ioh, CONADDR);
1476 	bus_space_unmap(iot, ioh, COM_NPORTS);
1477 	if (!found) {
1478 		cp->cn_pri = CN_DEAD;
1479 		return;
1480 	}
1481 
1482 	/* locate the major number */
1483 	for (commajor = 0; commajor < nchrdev; commajor++)
1484 		if (cdevsw[commajor].d_open == comopen)
1485 			break;
1486 
1487 	/* initialize required fields */
1488 	cp->cn_dev = makedev(commajor, CONUNIT);
1489 #ifdef	COMCONSOLE
1490 	cp->cn_pri = CN_REMOTE;		/* Force a serial port console */
1491 #else
1492 	cp->cn_pri = CN_NORMAL;
1493 #endif
1494 }
1495 
1496 void
1497 comcninit(cp)
1498 	struct consdev *cp;
1499 {
1500 
1501 #if 0
1502 	XXX NEEDS TO BE FIXED XXX
1503 	comconstag = ???;
1504 #endif
1505 	if (bus_space_map(comconstag, CONADDR, COM_NPORTS, 0, &comconsioh))
1506 		panic("comcninit: mapping failed");
1507 
1508 	cominitcons(comconstag, comconsioh, comconsrate);
1509 	comconsaddr = CONADDR;
1510 }
1511 
1512 /*
1513  * Initialize UART to known state.
1514  */
1515 void
1516 cominit(iot, ioh, rate)
1517 	bus_space_tag_t iot;
1518 	bus_space_handle_t ioh;
1519 	int rate;
1520 {
1521 
1522 	bus_space_write_1(iot, ioh, com_lcr, LCR_DLAB);
1523 	rate = comspeed(rate);
1524 	bus_space_write_1(iot, ioh, com_dlbl, rate);
1525 	bus_space_write_1(iot, ioh, com_dlbh, rate >> 8);
1526 	bus_space_write_1(iot, ioh, com_lcr, LCR_8BITS);
1527 	bus_space_write_1(iot, ioh, com_mcr, 0);
1528 	bus_space_write_1(iot, ioh, com_fifo,
1529 	    FIFO_ENABLE | FIFO_RCV_RST | FIFO_XMT_RST | FIFO_TRIGGER_1);
1530 	bus_space_write_1(iot, ioh, com_ier, 0);
1531 }
1532 
1533 /*
1534  * Set UART for console use. Do normal init, then enable interrupts.
1535  */
1536 void
1537 cominitcons(iot, ioh, rate)
1538 	bus_space_tag_t iot;
1539 	bus_space_handle_t ioh;
1540 	int rate;
1541 {
1542 	int s = splserial();
1543 	u_char stat;
1544 
1545 	cominit(iot, ioh, rate);
1546 	bus_space_write_1(iot, ioh, com_ier, IER_ERXRDY | IER_ETXRDY);
1547 	bus_space_write_1(iot, ioh, com_mcr, MCR_DTR | MCR_RTS);
1548 	DELAY(100);
1549 	stat = bus_space_read_1(iot, ioh, com_iir);
1550 	splx(s);
1551 }
1552 
1553 int
1554 comcngetc(dev)
1555 	dev_t dev;
1556 {
1557 	int s = splserial();
1558 	bus_space_tag_t iot = comconstag;
1559 	bus_space_handle_t ioh = comconsioh;
1560 	u_char stat, c;
1561 
1562 	while (!ISSET(stat = bus_space_read_1(iot, ioh, com_lsr), LSR_RXRDY))
1563 		;
1564 	c = bus_space_read_1(iot, ioh, com_data);
1565 	stat = bus_space_read_1(iot, ioh, com_iir);
1566 	splx(s);
1567 	return (c);
1568 }
1569 
1570 /*
1571  * Console kernel output character routine.
1572  */
1573 void
1574 comcnputc(dev, c)
1575 	dev_t dev;
1576 	int c;
1577 {
1578 	int s = splserial();
1579 	bus_space_tag_t iot = comconstag;
1580 	bus_space_handle_t ioh = comconsioh;
1581 	u_char stat;
1582 	register int timo;
1583 
1584 	/* wait for any pending transmission to finish */
1585 	timo = 50000;
1586 	while (!ISSET(stat = bus_space_read_1(iot, ioh, com_lsr), LSR_TXRDY) && --timo)
1587 		;
1588 	bus_space_write_1(iot, ioh, com_data, c);
1589 	/* wait for this transmission to complete */
1590 	timo = 1500000;
1591 	while (!ISSET(stat = bus_space_read_1(iot, ioh, com_lsr), LSR_TXRDY) && --timo)
1592 		;
1593 	/* clear any interrupts generated by this transmission */
1594 	stat = bus_space_read_1(iot, ioh, com_iir);
1595 	splx(s);
1596 }
1597 
1598 void
1599 comcnpollc(dev, on)
1600 	dev_t dev;
1601 	int on;
1602 {
1603 
1604 }
1605