xref: /netbsd-src/sys/dev/ic/cd18xx.c (revision ce2c90c7c172d95d2402a5b3d96d8f8e6d138a21)
1 /*	$NetBSD: cd18xx.c,v 1.18 2006/10/01 20:31:50 elad Exp $	*/
2 
3 /* XXXad does this even compile? */
4 
5 /*
6  * Copyright (c) 1998, 2001 Matthew R. Green
7  * All rights reserved.
8  *
9  * Redistribution and use in source and binary forms, with or without
10  * modification, are permitted provided that the following conditions
11  * are met:
12  * 1. Redistributions of source code must retain the above copyright
13  *    notice, this list of conditions and the following disclaimer.
14  * 2. Redistributions in binary form must reproduce the above copyright
15  *    notice, this list of conditions and the following disclaimer in the
16  *    documentation and/or other materials provided with the distribution.
17  * 3. The name of the author may not be used to endorse or promote products
18  *    derived from this software without specific prior written permission.
19  *
20  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
21  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
22  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
23  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
24  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
25  * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
26  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
27  * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
28  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
29  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
30  * SUCH DAMAGE.
31  */
32 
33 /*-
34  * Copyright (c) 1998, 1999 The NetBSD Foundation, Inc.
35  * All rights reserved.
36  *
37  * This code is derived from software contributed to The NetBSD Foundation
38  * by Charles M. Hannum.
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 NetBSD
51  *        Foundation, Inc. and its contributors.
52  * 4. Neither the name of The NetBSD Foundation nor the names of its
53  *    contributors may be used to endorse or promote products derived
54  *    from this software without specific prior written permission.
55  *
56  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
57  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
58  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
59  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
60  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
61  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
62  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
63  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
64  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
65  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
66  * POSSIBILITY OF SUCH DAMAGE.
67  */
68 
69 /*
70  * Copyright (c) 1991 The Regents of the University of California.
71  * All rights reserved.
72  *
73  * Redistribution and use in source and binary forms, with or without
74  * modification, are permitted provided that the following conditions
75  * are met:
76  * 1. Redistributions of source code must retain the above copyright
77  *    notice, this list of conditions and the following disclaimer.
78  * 2. Redistributions in binary form must reproduce the above copyright
79  *    notice, this list of conditions and the following disclaimer in the
80  *    documentation and/or other materials provided with the distribution.
81  * 3. Neither the name of the University nor the names of its contributors
82  *    may be used to endorse or promote products derived from this software
83  *    without specific prior written permission.
84  *
85  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
86  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
87  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
88  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
89  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
90  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
91  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
92  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
93  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
94  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
95  * SUCH DAMAGE.
96  *
97  *	@(#)com.c	7.5 (Berkeley) 5/16/91
98  */
99 
100 /*
101  * cirrus logic CL-CD180/CD1864/CD1865 driver, based in (large) parts on
102  * the com and z8530 drivers.  thanks charles.
103  */
104 
105 #include <sys/cdefs.h>
106 __KERNEL_RCSID(0, "$NetBSD: cd18xx.c,v 1.18 2006/10/01 20:31:50 elad Exp $");
107 
108 #include <sys/param.h>
109 #include <sys/conf.h>
110 #include <sys/device.h>
111 #include <sys/systm.h>
112 #include <sys/malloc.h>
113 #include <sys/proc.h>
114 #include <sys/kernel.h>
115 #include <sys/tty.h>
116 #include <sys/fcntl.h>
117 #include <sys/kauth.h>
118 
119 #include <machine/bus.h>
120 
121 #include <dev/ic/cd18xxvar.h>
122 #include <dev/ic/cd18xxreg.h>
123 
124 #include "ioconf.h"
125 
126 /*
127  * some helpers
128  */
129 
130 /* macros to clear/set/test flags. */
131 #define SET(t, f)	(t) |= (f)
132 #define CLR(t, f)	(t) &= ~(f)
133 #define ISSET(t, f)	((t) & (f))
134 
135 static void	cdtty_attach(struct cd18xx_softc *, int);
136 
137 static inline void cd18xx_rint(struct cd18xx_softc *, int *);
138 static inline void cd18xx_tint(struct cd18xx_softc *, int *);
139 static inline void cd18xx_mint(struct cd18xx_softc *, int *);
140 
141 void cdtty_rxsoft(struct cd18xx_softc *, struct cdtty_port *, struct tty *);
142 void cdtty_txsoft(struct cd18xx_softc *, struct cdtty_port *, struct tty *);
143 void cdtty_stsoft(struct cd18xx_softc *, struct cdtty_port *, struct tty *);
144 void cd18xx_softintr(void *);
145 
146 dev_type_open(cdttyopen);
147 dev_type_close(cdttyclose);
148 dev_type_read(cdttyread);
149 dev_type_write(cdttywrite);
150 dev_type_ioctl(cdttyioctl);
151 dev_type_stop(cdttystop);
152 dev_type_tty(cdttytty);
153 dev_type_poll(cdttypoll);
154 
155 const struct cdevsw cdtty_cdevsw = {
156 	cdttyopen, cdttyclose, cdttyread, cdttywrite, cdttyioctl,
157 	cdttystop, cdttytty, cdttypoll, nommap, ttykqfilter, D_TTY
158 };
159 
160 static void	cdtty_shutdown(struct cd18xx_softc *, struct cdtty_port *);
161 static void	cdttystart(struct tty *);
162 static int	cdttyparam(struct tty *, struct termios *);
163 static void	cdtty_break(struct cd18xx_softc *, struct cdtty_port *, int);
164 static void	cdtty_modem(struct cd18xx_softc *, struct cdtty_port *, int);
165 static int	cdttyhwiflow(struct tty *, int);
166 static void	cdtty_hwiflow(struct cd18xx_softc *, struct cdtty_port *);
167 
168 static void	cdtty_loadchannelregs(struct cd18xx_softc *,
169 					   struct cdtty_port *);
170 
171 /* default read buffer size */
172 u_int cdtty_rbuf_size = CDTTY_RING_SIZE;
173 
174 /* Stop input when 3/4 of the ring is full; restart when only 1/4 is full. */
175 u_int cdtty_rbuf_hiwat = (CDTTY_RING_SIZE * 1) / 4;
176 u_int cdtty_rbuf_lowat = (CDTTY_RING_SIZE * 3) / 4;
177 
178 #define CD18XXDEBUG
179 #ifdef CD18XXDEBUG
180 #define CDD_INFO	0x0001
181 #define CDD_INTR	0x0002
182 int cd18xx_debug = CDD_INTR|CDD_INFO;
183 # define DPRINTF(l, x)	if (cd18xx_debug & l) printf x
184 #else
185 # define DPRINTF(l, x)	/* nothing */
186 #endif
187 
188 /* Known supported revisions. */
189 struct cd18xx_revs {
190 	u_char	revision;
191 	u_char	onehundred_pin;
192 	char	*name;
193 } cd18xx_revs[] = {
194 	{ CD180_GFRCR_REV_B,		0, "CL-CD180 rev. B" },
195 	{ CD180_GFRCR_REV_C,		0, "CL-CD180 rev. C" },
196 	{ CD1864_GFRCR_REVISION_A,	1, "CL-CD1864 rev. A" },
197 	{ CD1865_GFRCR_REVISION_A,	1, "CL-CD1865 rev. A" },
198 	{ CD1865_GFRCR_REVISION_B,	1, "CL-CD1865 rev. B" },
199 	{ CD1865_GFRCR_REVISION_C,	1, "CL-CD1865 rev. C" },
200 	{ 0, 0, 0 }
201 };
202 
203 /* wait for the CCR to go to zero */
204 static inline int cd18xx_wait_ccr(struct cd18xx_softc *);
205 static inline int
206 cd18xx_wait_ccr(sc)
207 	struct cd18xx_softc *sc;
208 {
209 	int i = 100000;
210 
211 	while (--i &&
212 	    bus_space_read_1(sc->sc_tag, sc->sc_handle, CD18xx_CCR) != 0)
213 		;
214 	return (i == 0);
215 }
216 
217 /*
218  * device attach routine, high-end portion
219  */
220 void
221 cd18xx_attach(sc)
222 	struct cd18xx_softc *sc;
223 {
224 	static int chip_id_next = 1;
225 	int onehundred_pin, revision, i, port;
226 
227 	/* read and print the revision */
228 	revision = cd18xx_read(sc, CD18xx_GFRCR);
229 	onehundred_pin = ISSET(cd18xx_read(sc, CD18xx_SRCR),CD18xx_SRCR_PKGTYP);
230 	for (i = 0; cd18xx_revs[i].name; i++)
231 		if (revision == cd18xx_revs[i].revision ||
232 		    onehundred_pin == cd18xx_revs[i].onehundred_pin) {
233 			printf(": %s", cd18xx_revs[i].name);
234 			break;
235 		}
236 
237 	if (cd18xx_revs[i].name == NULL) {
238 		printf("%s: unknown revision, bailing.\n", sc->sc_dev.dv_xname);
239 		return;
240 	}
241 
242 	/* prepare for reset */
243 	cd18xx_set_car(sc, 0);
244 	cd18xx_write(sc, CD18xx_GSVR, CD18xx_GSVR_CLEAR);
245 
246 	/* wait for CCR to go to zero */
247 	if (cd18xx_wait_ccr(sc)) {
248 		printf("cd18xx_attach: reset change command timed out\n");
249 		return;
250 	}
251 
252 	/* full reset of all channels */
253 	cd18xx_write(sc, CD18xx_CCR,
254 	    CD18xx_CCR_RESET|CD18xx_CCR_RESET_HARD);
255 
256 	/* loop until the GSVR is ready */
257 	i = 100000;
258 	while (--i && cd18xx_read(sc, CD18xx_GSVR) == CD18xx_GSVR_READY)
259 		;
260 	if (i == 0) {
261 		printf("\n%s: did not reset!\n", sc->sc_dev.dv_xname);
262 		return;
263 	}
264 
265 	/* write the chip_id */
266 	sc->sc_chip_id = chip_id_next++;
267 #ifdef DIAGNOSTIC
268 	if (sc->sc_chip_id > 31)
269 		panic("more than 31 cd18xx's?  help.");
270 #endif
271 	cd18xx_write(sc, CD18xx_GSVR, CD18xx_GSVR_SETID(sc));
272 
273 	/* rx/tx/modem service match vectors, initalised by higher level */
274 	cd18xx_write(sc, CD18xx_MSMR, sc->sc_msmr | 0x80);
275 	cd18xx_write(sc, CD18xx_TSMR, sc->sc_tsmr | 0x80);
276 	cd18xx_write(sc, CD18xx_RSMR, sc->sc_rsmr | 0x80);
277 
278 	printf(", gsvr %x msmr %x tsmr %x rsmr %x",
279 	    cd18xx_read(sc, CD18xx_GSVR),
280 	    cd18xx_read(sc, CD18xx_MSMR),
281 	    cd18xx_read(sc, CD18xx_TSMR),
282 	    cd18xx_read(sc, CD18xx_RSMR));
283 
284 	/* prescale registers */
285 	sc->sc_pprh = 0xf0;
286 	sc->sc_pprl = 0;
287 	cd18xx_write(sc, CD18xx_PPRH, sc->sc_pprh);
288 	cd18xx_write(sc, CD18xx_PPRL, sc->sc_pprl);
289 
290 	/* establish our soft interrupt. */
291 	sc->sc_si = softintr_establish(IPL_SOFTSERIAL, cd18xx_softintr, sc);
292 
293 	printf(", 8 ports ready (chip id %d)\n", sc->sc_chip_id);
294 
295 	/*
296 	 * finally, we loop over all 8 channels initialising them
297 	 */
298 	for (port = 0; port < 8; port++)
299 		cdtty_attach(sc, port);
300 }
301 
302 /* tty portion of the code */
303 
304 /*
305  * tty portion attach routine
306  */
307 void
308 cdtty_attach(sc, port)
309 	struct	cd18xx_softc *sc;
310 	int port;
311 {
312 	struct cdtty_port *p = &sc->sc_ports[port];
313 	int i;
314 
315 	/* load CAR with channel number */
316 	cd18xx_set_car(sc, port);
317 
318 	/* wait for CCR to go to zero */
319 	if (cd18xx_wait_ccr(sc)) {
320 		printf("cd18xx_attach: change command timed out setting "
321 		       "CAR for port %d\n", i);
322 		return;
323 	}
324 
325 	/* set the RPTR to (arbitrary) 8 */
326 	cd18xx_write(sc, CD18xx_RTPR, 8);
327 
328 	/* reset the modem signal value register */
329 	sc->sc_ports[port].p_msvr = CD18xx_MSVR_RESET;
330 
331 	/* zero the service request enable register */
332 	cd18xx_write(sc, CD18xx_SRER, 0);
333 
334 	/* enable the transmitter & receiver */
335 	SET(p->p_chanctl, CD18xx_CCR_CHANCTL |
336 		          CD18xx_CCR_CHANCTL_TxEN |
337 		          CD18xx_CCR_CHANCTL_RxEN);
338 
339 	/* XXX no console or kgdb support yet! */
340 
341 	/* get a tty structure */
342 	p->p_tty = ttymalloc();
343 	p->p_tty->t_oproc = cdttystart;
344 	p->p_tty->t_param = cdttyparam;
345 	p->p_tty->t_hwiflow = cdttyhwiflow;
346 
347 	p->p_rbuf = malloc(cdtty_rbuf_size << 1, M_DEVBUF, M_WAITOK);
348 	p->p_rbput = p->p_rbget = p->p_rbuf;
349 	p->p_rbavail = cdtty_rbuf_size;
350 	if (p->p_rbuf == NULL) {
351 		printf("%s: unable to allocate ring buffer for tty %d\n",
352 		    sc->sc_dev.dv_xname, port);
353 		return;
354 	}
355 	p->p_ebuf = p->p_rbuf + (cdtty_rbuf_size << 1);
356 
357 	tty_attach(p->p_tty);
358 }
359 
360 /*
361  * cdtty_shutdown: called when the device is last closed.
362  */
363 void
364 cdtty_shutdown(sc, p)
365 	struct cd18xx_softc *sc;
366 	struct cdtty_port *p;
367 {
368 	struct tty *tp = p->p_tty;
369 	int s;
370 
371 	s = splserial();
372 
373 	/* If we were asserting flow control, then deassert it. */
374 	SET(p->p_rx_flags, RX_IBUF_BLOCKED);
375 	cdtty_hwiflow(sc, p);
376 
377 	/* Clear any break condition set with TIOCSBRK. */
378 	cdtty_break(sc, p, 0);
379 
380 	/*
381 	 * Hang up if necessary.  Wait a bit, so the other side has time to
382 	 * notice even if we immediately open the port again.
383 	 * Avoid tsleeping above splhigh().
384 	 */
385 	if (ISSET(tp->t_cflag, HUPCL)) {
386 		cdtty_modem(sc, p, 0);
387 		splx(s);
388 		/* XXX tsleep will only timeout */
389 		(void) tsleep(sc, TTIPRI, ttclos, hz);
390 		s = splserial();
391 	}
392 
393 	/* Turn off interrupts. */
394 	p->p_srer = 0;
395 	cd18xx_write(sc, CD18xx_SRER, p->p_srer);
396 
397 	splx(s);
398 }
399 
400 /*
401  * cdttyopen:  open syscall for cdtty terminals..
402  */
403 int
404 cdttyopen(dev, flag, mode, p)
405 	dev_t dev;
406 	int flag;
407 	int mode;
408 	struct proc *p;
409 {
410 	struct tty *tp;
411 	struct cd18xx_softc *sc;
412 	struct cdtty_port *port;
413 	int channel, instance, s, error;
414 
415 	channel = CD18XX_CHANNEL(dev);
416 	instance = CD18XX_INSTANCE(dev);
417 
418 	/* ensure instance is valid */
419 	if (instance >= clcd_cd.cd_ndevs)
420 		return (ENXIO);
421 
422 	/* get softc and port */
423 	sc = clcd_cd.cd_devs[instance];
424 	if (sc == NULL)
425 		return (ENXIO);
426 	port = &sc->sc_ports[channel];
427 	if (port == NULL || port->p_rbuf == NULL)
428 		return (ENXIO);
429 
430 	/* kgdb support?  maybe later... */
431 
432 	tp = port->p_tty;
433 
434 	if (kauth_authorize_device_tty(l->l_cred, KAUTH_DEVICE_TTY_OPEN, tp))
435 		return (EBUSY);
436 
437 	s = spltty();
438 
439 	/*
440 	 * Do the following iff this is a first open.
441 	 */
442 	if (!ISSET(tp->t_state, TS_ISOPEN) && tp->t_wopen == 0) {
443 		struct termios t;
444 
445 		/* set up things in tp as necessary */
446 		tp->t_dev = dev;
447 
448 		/*
449 		 * Initialize the termios status to the defaults.  Add in the
450 		 * sticky bits from TIOCSFLAGS.
451 		 */
452 		t.c_ispeed = 0;
453 		t.c_ospeed = TTYDEF_SPEED;
454 		t.c_cflag = TTYDEF_CFLAG;
455 
456 		if (ISSET(port->p_swflags, TIOCFLAG_CLOCAL))
457 			SET(t.c_cflag, CLOCAL);
458 		if (ISSET(port->p_swflags, TIOCFLAG_CRTSCTS))
459 			SET(t.c_cflag, CRTSCTS);
460 		if (ISSET(port->p_swflags, TIOCFLAG_CDTRCTS))
461 			SET(t.c_cflag, CDTRCTS);
462 		if (ISSET(port->p_swflags, TIOCFLAG_MDMBUF))
463 			SET(t.c_cflag, MDMBUF);
464 
465 		/* Make sure param will see changes. */
466 		tp->t_ospeed = 0;	/* XXX set above ignored? */
467 		(void)cdttyparam(tp, &t);
468 
469 		tp->t_iflag = TTYDEF_IFLAG;
470 		tp->t_oflag = TTYDEF_OFLAG;
471 		tp->t_lflag = TTYDEF_LFLAG;
472 		ttychars(tp);
473 		ttsetwater(tp);
474 
475 		(void)splserial();
476 
477 		/* turn on rx and modem interrupts */
478 		cd18xx_set_car(sc, CD18XX_CHANNEL(dev));
479 		SET(port->p_srer, CD18xx_SRER_Rx |
480 				  CD18xx_SRER_RxSC |
481 				  CD18xx_SRER_CD);
482 		cd18xx_write(sc, CD18xx_SRER, port->p_srer);
483 
484 		/* always turn on DTR when open */
485 		cdtty_modem(sc, port, 1);
486 
487 		/* initialise ring buffer */
488 		port->p_rbget = port->p_rbput = port->p_rbuf;
489 		port->p_rbavail = cdtty_rbuf_size;
490 		CLR(port->p_rx_flags, RX_ANY_BLOCK);
491 		cdtty_hwiflow(sc, port);
492 	}
493 
494 	/* drop spl back before going into the line open */
495 	splx(s);
496 
497 	error = ttyopen(tp, CD18XX_DIALOUT(dev), ISSET(flag, O_NONBLOCK));
498 	if (error == 0)
499 		error = (*tp->t_linesw->l_open)(dev, tp);
500 
501 	return (error);
502 }
503 
504 /*
505  * cdttyclose:  close syscall for cdtty terminals..
506  */
507 int
508 cdttyclose(dev, flag, mode, p)
509 	dev_t dev;
510 	int flag;
511 	int mode;
512 	struct proc *p;
513 {
514 	struct cd18xx_softc *sc;
515 	struct cdtty_port *port;
516 	struct tty *tp;
517 	int channel, instance;
518 
519 	channel = CD18XX_CHANNEL(dev);
520 	instance = CD18XX_INSTANCE(dev);
521 
522 	/* ensure instance is valid */
523 	if (instance >= clcd_cd.cd_ndevs)
524 		return (ENXIO);
525 
526 	/* get softc and port */
527 	sc = clcd_cd.cd_devs[instance];
528 	if (sc == NULL)
529 		return (ENXIO);
530 	port = &sc->sc_ports[channel];
531 
532 	tp = port->p_tty;
533 
534 	(*tp->t_linesw->l_close)(tp, flag);
535 	ttyclose(tp);
536 
537 	if (!ISSET(tp->t_state, TS_ISOPEN) && tp->t_wopen == 0) {
538 		/*
539 		 * Although we got a last close, the device may still be in
540 		 * use; e.g. if this was the dialout node, and there are still
541 		 * processes waiting for carrier on the non-dialout node.
542 		 */
543 		cdtty_shutdown(sc, port);
544 	}
545 
546 	return (0);
547 }
548 
549 /*
550  * cdttyread:  read syscall for cdtty terminals..
551  */
552 int
553 cdttyread(dev, uio, flag)
554 	dev_t dev;
555 	struct uio *uio;
556 	int flag;
557 {
558 	struct cd18xx_softc *sc = clcd_cd.cd_devs[CD18XX_INSTANCE(dev)];
559 	struct cdtty_port *port = &sc->sc_ports[CD18XX_CHANNEL(dev)];
560 	struct tty *tp = port->p_tty;
561 
562 	return ((*tp->t_linesw->l_read)(tp, uio, flag));
563 }
564 
565 /*
566  * cdttywrite:  write syscall for cdtty terminals..
567  */
568 int
569 cdttywrite(dev, uio, flag)
570 	dev_t dev;
571 	struct uio *uio;
572 	int flag;
573 {
574 	struct cd18xx_softc *sc = clcd_cd.cd_devs[CD18XX_INSTANCE(dev)];
575 	struct cdtty_port *port = &sc->sc_ports[CD18XX_CHANNEL(dev)];
576 	struct tty *tp = port->p_tty;
577 
578 	return ((*tp->t_linesw->l_write)(tp, uio, flag));
579 }
580 
581 int
582 cdttypoll(dev, events, p)
583 	dev_t dev;
584 	int events;
585 	struct proc *p;
586 {
587 	struct cd18xx_softc *sc = clcd_cd.cd_devs[CD18XX_INSTANCE(dev)];
588 	struct cdtty_port *port = &sc->sc_ports[CD18XX_CHANNEL(dev)];
589 	struct tty *tp = port->p_tty;
590 
591 	return ((*tp->t_linesw->l_poll)(tp, events, p));
592 }
593 
594 /*
595  * cdttytty:  return a pointer to our (cdtty) tp.
596  */
597 struct tty *
598 cdttytty(dev)
599 	dev_t dev;
600 {
601 	struct cd18xx_softc *sc = clcd_cd.cd_devs[CD18XX_INSTANCE(dev)];
602 	struct cdtty_port *port = &sc->sc_ports[CD18XX_CHANNEL(dev)];
603 
604 	return (port->p_tty);
605 }
606 
607 /*
608  * cdttyioctl:  ioctl syscall for cdtty terminals..
609  */
610 int
611 cdttyioctl(dev, cmd, data, flag, p)
612 	dev_t dev;
613 	u_long cmd;
614 	caddr_t data;
615 	int flag;
616 	struct proc *p;
617 {
618 	struct cd18xx_softc *sc = clcd_cd.cd_devs[CD18XX_INSTANCE(dev)];
619 	struct cdtty_port *port = &sc->sc_ports[CD18XX_CHANNEL(dev)];
620 	struct tty *tp = port->p_tty;
621 	int error, s;
622 
623 	error = (*tp->t_linesw->l_ioctl)(tp, cmd, data, flag, p);
624 	if (error != EPASSTHROUGH)
625 		return (error);
626 
627 	error = ttioctl(tp, cmd, data, flag, p);
628 	if (error != EPASSTHROUGH)
629 		return (error);
630 
631 	s = splserial();
632 
633 	switch (cmd) {
634 	case TIOCSBRK:
635 		cdtty_break(sc, port, 1);
636 		break;
637 
638 	case TIOCCBRK:
639 		cdtty_break(sc, port, 0);
640 		break;
641 
642 	case TIOCSDTR:
643 		cdtty_modem(sc, port, 1);
644 		break;
645 
646 	case TIOCCDTR:
647 		cdtty_modem(sc, port, 0);
648 		break;
649 
650 	case TIOCGFLAGS:
651 		*(int *)data = port->p_swflags;
652 		break;
653 
654 	case TIOCSFLAGS:
655 		error = kauth_authorize_device_tty(l->l_cred,
656 		    KAUTH_DEVICE_TTY_PRIVSET, tp);
657 		if (error)
658 			return (error);
659 		port->p_swflags = *(int *)data;
660 		break;
661 
662 	case TIOCMSET:
663 	case TIOCMBIS:
664 	case TIOCMBIC:
665 	case TIOCMGET:
666 	default:
667 		return (EPASSTHROUGH);
668 	}
669 
670 	splx(s);
671 	return (0);
672 }
673 
674 /*
675  * Start or restart transmission.
676  */
677 static void
678 cdttystart(tp)
679 	struct tty *tp;
680 {
681 	struct cd18xx_softc *sc = clcd_cd.cd_devs[CD18XX_INSTANCE(tp->t_dev)];
682 	struct cdtty_port *p = &sc->sc_ports[CD18XX_CHANNEL(tp->t_dev)];
683 	int s;
684 
685 	s = spltty();
686 	if (ISSET(tp->t_state, TS_BUSY | TS_TIMEOUT | TS_TTSTOP))
687 		goto out;
688 	if (p->p_tx_stopped)
689 		goto out;
690 
691 	if (tp->t_outq.c_cc <= tp->t_lowat) {
692 		if (ISSET(tp->t_state, TS_ASLEEP)) {
693 			CLR(tp->t_state, TS_ASLEEP);
694 			wakeup((caddr_t)&tp->t_outq);
695 		}
696 		selwakeup(&tp->t_wsel);
697 		if (tp->t_outq.c_cc == 0)
698 			goto out;
699 	}
700 
701 	/* Grab the first contiguous region of buffer space. */
702 	{
703 		u_char *tba;
704 		int tbc;
705 
706 		tba = tp->t_outq.c_cf;
707 		tbc = ndqb(&tp->t_outq, 0);
708 
709 		(void)splserial();
710 
711 		p->p_tba = tba;
712 		p->p_tbc = tbc;
713 	}
714 
715 	SET(tp->t_state, TS_BUSY);
716 	p->p_tx_busy = 1;
717 
718 	/* turn on tx interrupts */
719 	if ((p->p_srer & CD18xx_SRER_Tx) == 0) {
720 		cd18xx_set_car(sc, CD18XX_CHANNEL(tp->t_dev));
721 		SET(p->p_srer, CD18xx_SRER_Tx);
722 		cd18xx_write(sc, CD18xx_SRER, p->p_srer);
723 	}
724 
725 	/*
726 	 * Now bail; we can't actually transmit bytes until we're in a
727 	 * transmit interrupt service routine.
728 	 */
729 out:
730 	splx(s);
731 	return;
732 }
733 
734 /*
735  * cdttystop:  handing ^S or other stop signals, for a cdtty
736  */
737 void
738 cdttystop(tp, flag)
739 	struct tty *tp;
740 	int flag;
741 {
742 	struct cd18xx_softc *sc = clcd_cd.cd_devs[CD18XX_INSTANCE(tp->t_dev)];
743 	struct cdtty_port *p = &sc->sc_ports[CD18XX_CHANNEL(tp->t_dev)];
744 	int s;
745 
746 	s = splserial();
747 	if (ISSET(tp->t_state, TS_BUSY)) {
748 		/* Stop transmitting at the next chunk. */
749 		p->p_tbc = 0;
750 		p->p_heldtbc = 0;
751 		if (!ISSET(tp->t_state, TS_TTSTOP))
752 			SET(tp->t_state, TS_FLUSH);
753 	}
754 	splx(s);
755 }
756 
757 /*
758  * load a channel's registers.
759  */
760 void
761 cdtty_loadchannelregs(sc, p)
762 	struct cd18xx_softc *sc;
763 	struct cdtty_port *p;
764 {
765 
766 	cd18xx_set_car(sc, CD18XX_CHANNEL(p->p_tty->t_dev));
767 	cd18xx_write(sc, CD18xx_SRER, p->p_srer);
768 	cd18xx_write(sc, CD18xx_MSVR, p->p_msvr_active = p->p_msvr);
769 	cd18xx_write(sc, CD18xx_COR1, p->p_cor1);
770 	cd18xx_write(sc, CD18xx_COR2, p->p_cor2);
771 	cd18xx_write(sc, CD18xx_COR3, p->p_cor3);
772 	/*
773 	 * COR2 and COR3 change commands are not required here for
774 	 * the CL-CD1865 but we do them anyway for simplicity.
775 	 */
776 	cd18xx_write(sc, CD18xx_CCR, CD18xx_CCR_CORCHG |
777 				     CD18xx_CCR_CORCHG_COR1 |
778 				     CD18xx_CCR_CORCHG_COR2 |
779 				     CD18xx_CCR_CORCHG_COR3);
780 	cd18xx_write(sc, CD18xx_RBPRH, p->p_rbprh);
781 	cd18xx_write(sc, CD18xx_RBPRL, p->p_rbprl);
782 	cd18xx_write(sc, CD18xx_TBPRH, p->p_tbprh);
783 	cd18xx_write(sc, CD18xx_TBPRL, p->p_tbprl);
784 	if (cd18xx_wait_ccr(sc)) {
785 		DPRINTF(CDD_INFO,
786 		    ("%s: cdtty_loadchannelregs ccr wait timed out\n",
787 		    sc->sc_dev.dv_xname));
788 	}
789 	cd18xx_write(sc, CD18xx_CCR, p->p_chanctl);
790 }
791 
792 /*
793  * Set tty parameters from termios.
794  * XXX - Should just copy the whole termios after
795  * making sure all the changes could be done.
796  */
797 static int
798 cdttyparam(tp, t)
799 	struct tty *tp;
800 	struct termios *t;
801 {
802 	struct cd18xx_softc *sc = clcd_cd.cd_devs[CD18XX_INSTANCE(tp->t_dev)];
803 	struct cdtty_port *p = &sc->sc_ports[CD18XX_CHANNEL(tp->t_dev)];
804 	int s;
805 
806 	/* Check requested parameters. */
807 	if (t->c_ospeed < 0)
808 		return (EINVAL);
809 	if (t->c_ispeed && t->c_ispeed != t->c_ospeed)
810 		return (EINVAL);
811 
812 	/*
813 	 * For the console, always force CLOCAL and !HUPCL, so that the port
814 	 * is always active.
815 	 */
816 	if (ISSET(p->p_swflags, TIOCFLAG_SOFTCAR)) {
817 		SET(t->c_cflag, CLOCAL);
818 		CLR(t->c_cflag, HUPCL);
819 	}
820 
821 	/*
822 	 * If there were no changes, don't do anything.  This avoids dropping
823 	 * input and improves performance when all we did was frob things like
824 	 * VMIN and VTIME.
825 	 */
826 	if (tp->t_ospeed == t->c_ospeed &&
827 	    tp->t_cflag == t->c_cflag)
828 		return (0);
829 
830 	/*
831 	 * Block interrupts so that state will not
832 	 * be altered until we are done setting it up.
833 	 */
834 	s = splserial();
835 
836 	/*
837 	 * Copy across the size, parity and stop bit info.
838 	 */
839 	switch (t->c_cflag & CSIZE) {
840 	case CS5:
841 		p->p_cor1 = CD18xx_COR1_CS5;
842 		break;
843 	case CS6:
844 		p->p_cor1 = CD18xx_COR1_CS6;
845 		break;
846 	case CS7:
847 		p->p_cor1 = CD18xx_COR1_CS7;
848 		break;
849 	default:
850 		p->p_cor1 = CD18xx_COR1_CS8;
851 		break;
852 	}
853 	if (ISSET(t->c_cflag, PARENB)) {
854 		SET(p->p_cor1, CD18xx_COR1_PARITY_NORMAL);
855 		if (ISSET(t->c_cflag, PARODD))
856 			SET(p->p_cor1, CD18xx_COR1_PARITY_ODD);
857 	}
858 	if (!ISSET(t->c_iflag, INPCK))
859 		SET(p->p_cor1, CD18xx_COR1_IGNORE);
860 	if (ISSET(t->c_cflag, CSTOPB))
861 		SET(p->p_cor1, CD18xx_COR1_STOPBIT_2);
862 
863 	/*
864 	 * If we're not in a mode that assumes a connection is present, then
865 	 * ignore carrier changes.
866 	 */
867 	if (ISSET(t->c_cflag, CLOCAL | MDMBUF))
868 		p->p_msvr_dcd = 0;
869 	else
870 		p->p_msvr_dcd = CD18xx_MSVR_CD;
871 
872 	/*
873 	 * Set the flow control pins depending on the current flow control
874 	 * mode.
875 	 */
876 	if (ISSET(t->c_cflag, CRTSCTS)) {
877 		p->p_mcor1_dtr = CD18xx_MCOR1_DTR;
878 		p->p_msvr_rts = CD18xx_MSVR_RTS;
879 		p->p_msvr_cts = CD18xx_MSVR_CTS;
880 		p->p_cor2 = CD18xx_COR2_RTSAOE|CD18xx_COR2_CTSAE;
881 	} else if (ISSET(t->c_cflag, MDMBUF)) {
882 		/*
883 		 * For DTR/DCD flow control, make sure we don't toggle DTR for
884 		 * carrier detection.
885 		 */
886 		p->p_mcor1_dtr = 0;
887 		p->p_msvr_rts = CD18xx_MSVR_DTR;
888 		p->p_msvr_cts = CD18xx_MSVR_CD;
889 		p->p_cor2 = 0;
890 	} else {
891 		/*
892 		 * If no flow control, then always set RTS.  This will make
893 		 * the other side happy if it mistakenly thinks we're doing
894 		 * RTS/CTS flow control.
895 		 */
896 		p->p_mcor1_dtr = CD18xx_MSVR_DTR;
897 		p->p_msvr_rts = 0;
898 		p->p_msvr_cts = 0;
899 		p->p_cor2 = 0;
900 	}
901 	p->p_msvr_mask = p->p_msvr_cts | p->p_msvr_dcd;
902 
903 	/*
904 	 * Set the FIFO threshold based on the receive speed.
905 	 *
906 	 *  * If it's a low speed, it's probably a mouse or some other
907 	 *    interactive device, so set the threshold low.
908 	 *  * If it's a high speed, trim the trigger level down to prevent
909 	 *    overflows.
910 	 *  * Otherwise set it a bit higher.
911 	 */
912 	p->p_cor3 = (t->c_ospeed <= 1200 ? 1 : t->c_ospeed <= 38400 ? 8 : 4);
913 
914 #define PORT_RATE(o, s)	\
915 	(((((o) + (s)/2) / (s)) + CD18xx_xBRPR_TPC/2) / CD18xx_xBRPR_TPC)
916 	/* Compute BPS for the requested speeds */
917 	if (t->c_ospeed) {
918 		u_int32_t tbpr = PORT_RATE(sc->sc_osc, t->c_ospeed);
919 
920 		if (tbpr == 0 || tbpr > 0xffff)
921 			return (EINVAL);
922 
923 		p->p_tbprh = tbpr >> 8;
924 		p->p_tbprl = tbpr & 0xff;
925 	}
926 
927 	if (t->c_ispeed) {
928 		u_int32_t rbpr = PORT_RATE(sc->sc_osc, t->c_ispeed);
929 
930 		if (rbpr == 0 || rbpr > 0xffff)
931 			return (EINVAL);
932 
933 		p->p_rbprh = rbpr >> 8;
934 		p->p_rbprl = rbpr & 0xff;
935 	}
936 
937 	/* And copy to tty. */
938 	tp->t_ispeed = 0;
939 	tp->t_ospeed = t->c_ospeed;
940 	tp->t_cflag = t->c_cflag;
941 
942 	if (!p->p_heldchange) {
943 		if (p->p_tx_busy) {
944 			p->p_heldtbc = p->p_tbc;
945 			p->p_tbc = 0;
946 			p->p_heldchange = 1;
947 		} else
948 			cdtty_loadchannelregs(sc, p);
949 	}
950 
951 	if (!ISSET(t->c_cflag, CHWFLOW)) {
952 		/* Disable the high water mark. */
953 		p->p_r_hiwat = 0;
954 		p->p_r_lowat = 0;
955 		if (ISSET(p->p_rx_flags, RX_TTY_OVERFLOWED)) {
956 			CLR(p->p_rx_flags, RX_TTY_OVERFLOWED);
957 			softintr_schedule(sc->sc_si);
958 		}
959 		if (ISSET(p->p_rx_flags, RX_TTY_BLOCKED|RX_IBUF_BLOCKED)) {
960 			CLR(p->p_rx_flags, RX_TTY_BLOCKED|RX_IBUF_BLOCKED);
961 			cdtty_hwiflow(sc, p);
962 		}
963 	} else {
964 		p->p_r_hiwat = cdtty_rbuf_hiwat;
965 		p->p_r_lowat = cdtty_rbuf_lowat;
966 	}
967 
968 	splx(s);
969 
970 	/*
971 	 * Update the tty layer's idea of the carrier bit, in case we changed
972 	 * CLOCAL or MDMBUF.  We don't hang up here; we only do that by
973 	 * explicit request.
974 	 */
975 	(void) (*tp->t_linesw->l_modem)(tp, ISSET(p->p_msvr, CD18xx_MSVR_CD));
976 
977 	if (!ISSET(t->c_cflag, CHWFLOW)) {
978 		if (p->p_tx_stopped) {
979 			p->p_tx_stopped = 0;
980 			cdttystart(tp);
981 		}
982 	}
983 
984 	return (0);
985 }
986 
987 static void
988 cdtty_break(sc, p, onoff)
989 	struct cd18xx_softc *sc;
990 	struct cdtty_port *p;
991 	int onoff;
992 {
993 
994 	/* tell tx intr handler we need a break */
995 	p->p_needbreak = !!onoff;
996 
997 	/* turn on tx interrupts if break has changed */
998 	if (p->p_needbreak != p->p_break)
999 		SET(p->p_srer, CD18xx_SRER_Tx);
1000 
1001 	if (!p->p_heldchange) {
1002 		if (p->p_tx_busy) {
1003 			p->p_heldtbc = p->p_tbc;
1004 			p->p_tbc = 0;
1005 			p->p_heldchange = 1;
1006 		} else
1007 			cdtty_loadchannelregs(sc, p);
1008 	}
1009 }
1010 
1011 /*
1012  * Raise or lower modem control (DTR/RTS) signals.  If a character is
1013  * in transmission, the change is deferred.
1014  */
1015 static void
1016 cdtty_modem(sc, p, onoff)
1017 	struct cd18xx_softc *sc;
1018 	struct cdtty_port *p;
1019 	int onoff;
1020 {
1021 
1022 	if (p->p_mcor1_dtr == 0)
1023 		return;
1024 
1025 	if (onoff)
1026 		CLR(p->p_mcor1, p->p_mcor1_dtr);
1027 	else
1028 		SET(p->p_mcor1, p->p_mcor1_dtr);
1029 
1030 	if (!p->p_heldchange) {
1031 		if (p->p_tx_busy) {
1032 			p->p_heldtbc = p->p_tbc;
1033 			p->p_tbc = 0;
1034 			p->p_heldchange = 1;
1035 		} else
1036 			cdtty_loadchannelregs(sc, p);
1037 	}
1038 }
1039 
1040 /*
1041  * Try to block or unblock input using hardware flow-control.
1042  * This is called by kern/tty.c if MDMBUF|CRTSCTS is set, and
1043  * if this function returns non-zero, the TS_TBLOCK flag will
1044  * be set or cleared according to the "block" arg passed.
1045  */
1046 int
1047 cdttyhwiflow(tp, block)
1048 	struct tty *tp;
1049 	int block;
1050 {
1051 	struct cd18xx_softc *sc = clcd_cd.cd_devs[CD18XX_INSTANCE(tp->t_dev)];
1052 	struct cdtty_port *p = &sc->sc_ports[CD18XX_CHANNEL(tp->t_dev)];
1053 	int s;
1054 
1055 	if (p->p_msvr_rts == 0)
1056 		return (0);
1057 
1058 	s = splserial();
1059 	if (block) {
1060 		if (!ISSET(p->p_rx_flags, RX_TTY_BLOCKED)) {
1061 			SET(p->p_rx_flags, RX_TTY_BLOCKED);
1062 			cdtty_hwiflow(sc, p);
1063 		}
1064 	} else {
1065 		if (ISSET(p->p_rx_flags, RX_TTY_OVERFLOWED)) {
1066 			CLR(p->p_rx_flags, RX_TTY_OVERFLOWED);
1067 			softintr_schedule(sc->sc_si);
1068 		}
1069 		if (ISSET(p->p_rx_flags, RX_TTY_BLOCKED)) {
1070 			CLR(p->p_rx_flags, RX_TTY_BLOCKED);
1071 			cdtty_hwiflow(sc, p);
1072 		}
1073 	}
1074 	splx(s);
1075 	return (1);
1076 }
1077 
1078 /*
1079  * Internal version of cdttyhwiflow, called at cdtty's priority.
1080  */
1081 static void
1082 cdtty_hwiflow(sc, p)
1083 	struct cd18xx_softc *sc;
1084 	struct cdtty_port *p;
1085 {
1086 
1087 	if (p->p_msvr_rts == 0)
1088 		return;
1089 
1090 	if (ISSET(p->p_rx_flags, RX_ANY_BLOCK)) {
1091 		CLR(p->p_msvr, p->p_msvr_rts);
1092 		CLR(p->p_msvr_active, p->p_msvr_rts);
1093 	} else {
1094 		SET(p->p_msvr, p->p_msvr_rts);
1095 		SET(p->p_msvr_active, p->p_msvr_rts);
1096 	}
1097 	cd18xx_set_car(sc, CD18XX_CHANNEL(p->p_tty->t_dev));
1098 	cd18xx_write(sc, CD18xx_MSVR, p->p_msvr_active);
1099 }
1100 
1101 /*
1102  * indiviual interrupt routines.
1103  */
1104 
1105 /*
1106  * this is the number of interrupts allowed, total.  set it to 0
1107  * to allow unlimited interrpts
1108  */
1109 #define INTR_MAX_ALLOWED	0
1110 
1111 #if INTR_MAX_ALLOWED == 0
1112 #define GOTINTR(sc, p)	/* nothing */
1113 #else
1114 int intrcount;
1115 #define GOTINTR(sc, p)	\
1116 do { \
1117 	if (intrcount++ == INTR_MAX_ALLOWED) { \
1118 		CLR(p->p_srer, CD18xx_SRER_Tx); \
1119 		cd18xx_write(sc, CD18xx_SRER, p->p_srer); \
1120 	} \
1121 	DPRINTF(CDD_INTR, (", intrcount %d srer %x", intrcount, p->p_srer)); \
1122 } while (0)
1123 #endif
1124 
1125 /* receiver interrupt */
1126 static inline void
1127 cd18xx_rint(sc, ns)
1128 	struct cd18xx_softc *sc;
1129 	int *ns;
1130 {
1131 	struct cdtty_port *p;
1132 	u_int channel, count;
1133 	u_char *put, *end;
1134 	u_int cc;
1135 
1136 	/* work out the channel and softc */
1137 	channel = cd18xx_get_gscr1_channel(sc);
1138 	p = &sc->sc_ports[channel];
1139 	DPRINTF(CDD_INTR, ("%s: rint: channel %d", sc->sc_dev.dv_xname, channel));
1140 	GOTINTR(sc, p);
1141 
1142 	end = p->p_ebuf;
1143 	put = p->p_rbput;
1144 	cc = p->p_rbavail;
1145 
1146 	/* read as many bytes as necessary */
1147 	count = cd18xx_read(sc, CD18xx_RDCR);
1148 	DPRINTF(CDD_INTR, (", %d bytes available: ", count));
1149 
1150 	while (cc > 0 && count > 0) {
1151 		u_char rcsr = cd18xx_read(sc, CD18xx_RCSR);
1152 
1153 		put[0] = cd18xx_read(sc, CD18xx_RDR);
1154 		put[1] = rcsr;
1155 
1156 		if (rcsr)
1157 			*ns = 1;
1158 
1159 		put += 2;
1160 		if (put >= end)
1161 			put = p->p_rbuf;
1162 
1163 		DPRINTF(CDD_INTR, ("."));
1164 		cc--;
1165 		count--;
1166 	}
1167 
1168 	DPRINTF(CDD_INTR, (" finished reading"));
1169 
1170 	/*
1171 	 * Current string of incoming characters ended because
1172 	 * no more data was available or we ran out of space.
1173 	 * If we're out of space, turn off receive interrupts.
1174 	 */
1175 	p->p_rbput = put;
1176 	p->p_rbavail = cc;
1177 	if (!ISSET(p->p_rx_flags, RX_TTY_OVERFLOWED)) {
1178 		p->p_rx_ready = 1;
1179 	}
1180 
1181 	/*
1182 	 * If we're out of space, disable receive interrupts
1183 	 * until the queue has drained a bit.
1184 	 */
1185 	if (!cc) {
1186 		SET(p->p_rx_flags, RX_IBUF_OVERFLOWED);
1187 		CLR(p->p_srer, CD18xx_SRER_Rx |
1188 			       CD18xx_SRER_RxSC |
1189 			       CD18xx_SRER_CD);
1190 		cd18xx_write(sc, CD18xx_SRER, p->p_srer);
1191 	}
1192 
1193 	/* finish the interrupt transaction with the IC */
1194 	cd18xx_write(sc, CD18xx_EOSRR, 0);
1195 	DPRINTF(CDD_INTR, (", done\n"));
1196 }
1197 
1198 /*
1199  * transmitter interrupt
1200  *
1201  * note this relys on the fact that we allow the transmitter FIFO to
1202  * drain completely
1203  */
1204 static inline void
1205 cd18xx_tint(sc, ns)
1206 	struct cd18xx_softc *sc;
1207 	int *ns;
1208 {
1209 	struct cdtty_port *p;
1210 	u_int channel;
1211 
1212 	/* work out the channel and softc */
1213 	channel = cd18xx_get_gscr1_channel(sc);
1214 	p = &sc->sc_ports[channel];
1215 	DPRINTF(CDD_INTR, ("%s: tint: channel %d", sc->sc_dev.dv_xname,
1216 	    channel));
1217 	GOTINTR(sc, p);
1218 
1219 	/* if the current break condition is wrong, fix it */
1220 	if (p->p_break != p->p_needbreak) {
1221 		u_char buf[2];
1222 
1223 		DPRINTF(CDD_INTR, (", changing break to %d", p->p_needbreak));
1224 
1225 		/* turn on ETC processing */
1226 		cd18xx_write(sc, CD18xx_COR2, p->p_cor2 | CD18xx_COR2_ETC);
1227 
1228 		buf[0] = CD18xx_TDR_ETC_BYTE;
1229 		buf[1] = p->p_needbreak ? CD18xx_TDR_BREAK_BYTE :
1230 					    CD18xx_TDR_NOBREAK_BYTE;
1231 		cd18xx_write_multi(sc, CD18xx_TDR, buf, 2);
1232 
1233 		p->p_break = p->p_needbreak;
1234 
1235 		/* turn off ETC processing */
1236 		cd18xx_write(sc, CD18xx_COR2, p->p_cor2);
1237 	}
1238 
1239 	/*
1240 	 * If we've delayed a parameter change, do it now, and restart
1241 	 * output.
1242 	 */
1243 	if (p->p_heldchange) {
1244 		cdtty_loadchannelregs(sc, p);
1245 		p->p_heldchange = 0;
1246 		p->p_tbc = p->p_heldtbc;
1247 		p->p_heldtbc = 0;
1248 	}
1249 
1250 	/* Output the next chunk of the contiguous buffer, if any. */
1251 	if (p->p_tbc > 0) {
1252 		int n;
1253 
1254 		n = p->p_tbc;
1255 		if (n > 8) /* write up to 8 entries */
1256 			n = 8;
1257 		DPRINTF(CDD_INTR, (", writing %d bytes to TDR", n));
1258 		cd18xx_write_multi(sc, CD18xx_TDR, p->p_tba, n);
1259 		p->p_tbc -= n;
1260 		p->p_tba += n;
1261 	}
1262 
1263 	/* Disable transmit completion interrupts if we ran out of bytes. */
1264 	if (p->p_tbc == 0) {
1265 		/* Note that Tx interrupts should already be enabled */
1266 		if (ISSET(p->p_srer, CD18xx_SRER_Tx)) {
1267 			DPRINTF(CDD_INTR, (", disabling tx interrupts"));
1268 			CLR(p->p_srer, CD18xx_SRER_Tx);
1269 			cd18xx_write(sc, CD18xx_SRER, p->p_srer);
1270 		}
1271 		if (p->p_tx_busy) {
1272 			p->p_tx_busy = 0;
1273 			p->p_tx_done = 1;
1274 		}
1275 	}
1276 	*ns = 1;
1277 
1278 	/* finish the interrupt transaction with the IC */
1279 	cd18xx_write(sc, CD18xx_EOSRR, 0);
1280 	DPRINTF(CDD_INTR, (", done\n"));
1281 }
1282 
1283 /* modem signal change interrupt */
1284 static inline void
1285 cd18xx_mint(sc, ns)
1286 	struct cd18xx_softc *sc;
1287 	int *ns;
1288 {
1289 	struct cdtty_port *p;
1290 	u_int channel;
1291 	u_char msvr, delta;
1292 
1293 	/* work out the channel and softc */
1294 	channel = cd18xx_get_gscr1_channel(sc);
1295 	p = &sc->sc_ports[channel];
1296 	DPRINTF(CDD_INTR, ("%s: mint: channel %d", sc->sc_dev.dv_xname, channel));
1297 	GOTINTR(sc, p);
1298 
1299 	/*
1300 	 * We ignore the MCR register, and handle detecting deltas
1301 	 * via software, like many other serial drivers.
1302 	 */
1303 	msvr = cd18xx_read(sc, CD18xx_MSVR);
1304 	delta = msvr ^ p->p_msvr;
1305 	DPRINTF(CDD_INTR, (", msvr %d", msvr));
1306 
1307 	/*
1308 	 * Process normal status changes
1309 	 */
1310 	if (ISSET(delta, p->p_msvr_mask)) {
1311 		SET(p->p_msvr_delta, delta);
1312 
1313 		DPRINTF(CDD_INTR, (", status changed delta %d", delta));
1314 		/*
1315 		 * Stop output immediately if we lose the output
1316 		 * flow control signal or carrier detect.
1317 		 */
1318 		if (ISSET(~msvr, p->p_msvr_mask)) {
1319 			p->p_tbc = 0;
1320 			p->p_heldtbc = 0;
1321 			/* Stop modem interrupt processing */
1322 		}
1323 		p->p_st_check = 1;
1324 		*ns = 1;
1325 	}
1326 
1327 	/* reset the modem signal register */
1328 	cd18xx_write(sc, CD18xx_MCR, 0);
1329 
1330 	/* finish the interrupt transaction with the IC */
1331 	cd18xx_write(sc, CD18xx_EOSRR, 0);
1332 	DPRINTF(CDD_INTR, (", done\n"));
1333 }
1334 
1335 /*
1336  * hardware interrupt routine.  call the relevant interrupt routines until
1337  * no interrupts are pending.
1338  *
1339  * note:  we do receive interrupts before all others (as we'd rather lose
1340  * a chance to transmit, than lose a character).  and we do transmit
1341  * interrupts before modem interrupts.
1342  *
1343  * we have to traverse all of the cd18xx's attached, unfortunately.
1344  */
1345 int
1346 cd18xx_hardintr(v)
1347 	void *v;
1348 {
1349 	int i, rv = 0;
1350 	u_char ack;
1351 
1352 	DPRINTF(CDD_INTR, ("cd18xx_hardintr (ndevs %d):\n", clcd_cd.cd_ndevs));
1353 	for (i = 0; i < clcd_cd.cd_ndevs; i++)
1354 	{
1355 		struct cd18xx_softc *sc = clcd_cd.cd_devs[i];
1356 		int status, ns = 0;
1357 		int count = 1;	/* process only 1 interrupts at a time for now */
1358 
1359 		if (sc == NULL)
1360 			continue;
1361 
1362 		DPRINTF(CDD_INTR, ("%s:", sc->sc_dev.dv_xname));
1363 		while (count-- &&
1364 		    (status = (cd18xx_read(sc, CD18xx_SRSR) &
1365 		     CD18xx_SRSR_PENDING))) {
1366 			rv = 1;
1367 
1368 			DPRINTF(CDD_INTR, (" status %x:", status));
1369 			if (ISSET(status, CD18xx_SRSR_RxPEND)) {
1370 				ack = (*sc->sc_ackfunc)(sc->sc_ackfunc_arg,
1371 				    CD18xx_INTRACK_RxINT);
1372 				DPRINTF(CDD_INTR, (" rx: ack1 %x\n", ack));
1373 				cd18xx_rint(sc, &ns);
1374 			}
1375 			if (ISSET(status, CD18xx_SRSR_TxPEND)) {
1376 				ack = (*sc->sc_ackfunc)(sc->sc_ackfunc_arg,
1377 				    CD18xx_INTRACK_TxINT);
1378 				DPRINTF(CDD_INTR, (" tx: ack1 %x\n", ack));
1379 				cd18xx_tint(sc, &ns);
1380 
1381 			}
1382 			if (ISSET(status, CD18xx_SRSR_MxPEND)) {
1383 				ack = (*sc->sc_ackfunc)(sc->sc_ackfunc_arg,
1384 				    CD18xx_INTRACK_MxINT);
1385 				DPRINTF(CDD_INTR, (" mx: ack1 %x\n", ack));
1386 				cd18xx_mint(sc, &ns);
1387 			}
1388 		}
1389 		if (ns)
1390 			softintr_schedule(sc->sc_si);
1391 	}
1392 
1393 	return (rv);
1394 }
1395 
1396 /*
1397  * software interrupt
1398  */
1399 
1400 void
1401 cdtty_rxsoft(sc, p, tp)
1402 	struct cd18xx_softc *sc;
1403 	struct cdtty_port *p;
1404 	struct tty *tp;
1405 {
1406 	u_char *get, *end;
1407 	u_int cc, scc;
1408 	u_char rcsr;
1409 	int code;
1410 	int s;
1411 
1412 	end = p->p_ebuf;
1413 	get = p->p_rbget;
1414 	scc = cc = cdtty_rbuf_size - p->p_rbavail;
1415 
1416 	if (cc == cdtty_rbuf_size) {
1417 		p->p_floods++;
1418 #if 0
1419 		if (p->p_errors++ == 0)
1420 			callout_reset(&p->p_diag_callout, 60 * hz,
1421 			    cdttydiag, p);
1422 #endif
1423 	}
1424 
1425 	while (cc) {
1426 		code = get[0];
1427 		rcsr = get[1];
1428 		if (ISSET(rcsr, CD18xx_RCSR_OVERRUNERR | CD18xx_RCSR_BREAK |
1429 				CD18xx_RCSR_FRAMERR | CD18xx_RCSR_PARITYERR)) {
1430 			if (ISSET(rcsr, CD18xx_RCSR_OVERRUNERR)) {
1431 				p->p_overflows++;
1432 #if 0
1433 				if (p->p_errors++ == 0)
1434 					callout_reset(&p->p_diag_callout,
1435 					    60 * hz, cdttydiag, p);
1436 #endif
1437 			}
1438 			if (ISSET(rcsr, CD18xx_RCSR_BREAK|CD18xx_RCSR_FRAMERR))
1439 				SET(code, TTY_FE);
1440 			if (ISSET(rcsr, CD18xx_RCSR_PARITYERR))
1441 				SET(code, TTY_PE);
1442 		}
1443 		if ((*tp->t_linesw->l_rint)(code, tp) == -1) {
1444 			/*
1445 			 * The line discipline's buffer is out of space.
1446 			 */
1447 			if (!ISSET(p->p_rx_flags, RX_TTY_BLOCKED)) {
1448 				/*
1449 				 * We're either not using flow control, or the
1450 				 * line discipline didn't tell us to block for
1451 				 * some reason.  Either way, we have no way to
1452 				 * know when there's more space available, so
1453 				 * just drop the rest of the data.
1454 				 */
1455 				get += cc << 1;
1456 				if (get >= end)
1457 					get -= cdtty_rbuf_size << 1;
1458 				cc = 0;
1459 			} else {
1460 				/*
1461 				 * Don't schedule any more receive processing
1462 				 * until the line discipline tells us there's
1463 				 * space available (through cdttyhwiflow()).
1464 				 * Leave the rest of the data in the input
1465 				 * buffer.
1466 				 */
1467 				SET(p->p_rx_flags, RX_TTY_OVERFLOWED);
1468 			}
1469 			break;
1470 		}
1471 		get += 2;
1472 		if (get >= end)
1473 			get = p->p_rbuf;
1474 		cc--;
1475 	}
1476 
1477 	if (cc != scc) {
1478 		p->p_rbget = get;
1479 		s = splserial();
1480 
1481 		cc = p->p_rbavail += scc - cc;
1482 		/* Buffers should be ok again, release possible block. */
1483 		if (cc >= p->p_r_lowat) {
1484 			if (ISSET(p->p_rx_flags, RX_IBUF_OVERFLOWED)) {
1485 				CLR(p->p_rx_flags, RX_IBUF_OVERFLOWED);
1486 				cd18xx_set_car(sc, CD18XX_CHANNEL(tp->t_dev));
1487 				SET(p->p_srer, CD18xx_SRER_Rx |
1488 					       CD18xx_SRER_RxSC |
1489 					       CD18xx_SRER_CD);
1490 				cd18xx_write(sc, CD18xx_SRER, p->p_srer);
1491 			}
1492 			if (ISSET(p->p_rx_flags, RX_IBUF_BLOCKED)) {
1493 				CLR(p->p_rx_flags, RX_IBUF_BLOCKED);
1494 				cdtty_hwiflow(sc, p);
1495 			}
1496 		}
1497 		splx(s);
1498 	}
1499 }
1500 
1501 void
1502 cdtty_txsoft(sc, p, tp)
1503 	struct cd18xx_softc *sc;
1504 	struct cdtty_port *p;
1505 	struct tty *tp;
1506 {
1507 
1508 	CLR(tp->t_state, TS_BUSY);
1509 	if (ISSET(tp->t_state, TS_FLUSH))
1510 		CLR(tp->t_state, TS_FLUSH);
1511 	else
1512 		ndflush(&tp->t_outq, (int)(p->p_tba - tp->t_outq.c_cf));
1513 	(*tp->t_linesw->l_start)(tp);
1514 }
1515 
1516 void
1517 cdtty_stsoft(sc, p, tp)
1518 	struct cd18xx_softc *sc;
1519 	struct cdtty_port *p;
1520 	struct tty *tp;
1521 {
1522 	u_char msvr, delta;
1523 	int s;
1524 
1525 	s = splserial();
1526 	msvr = p->p_msvr;
1527 	delta = p->p_msvr_delta;
1528 	p->p_msvr_delta = 0;
1529 	splx(s);
1530 
1531 	if (ISSET(delta, p->p_msvr_dcd)) {
1532 		/*
1533 		 * Inform the tty layer that carrier detect changed.
1534 		 */
1535 		(void) (*tp->t_linesw->l_modem)(tp, ISSET(msvr, CD18xx_MSVR_CD));
1536 	}
1537 
1538 	if (ISSET(delta, p->p_msvr_cts)) {
1539 		/* Block or unblock output according to flow control. */
1540 		if (ISSET(msvr, p->p_msvr_cts)) {
1541 			p->p_tx_stopped = 0;
1542 			(*tp->t_linesw->l_start)(tp);
1543 		} else {
1544 			p->p_tx_stopped = 1;
1545 		}
1546 	}
1547 }
1548 
1549 void
1550 cd18xx_softintr(v)
1551 	void *v;
1552 {
1553 	struct cd18xx_softc *sc = v;
1554 	struct cdtty_port *p;
1555 	struct tty *tp;
1556 	int i;
1557 
1558 	for (i = 0; i < 8; i++) {
1559 		p = &sc->sc_ports[i];
1560 
1561 		tp = p->p_tty;
1562 		if (tp == NULL)
1563 			continue;
1564 		if (!ISSET(tp->t_state, TS_ISOPEN) && tp->t_wopen == 0)
1565 			continue;
1566 
1567 		if (p->p_rx_ready) {
1568 			p->p_rx_ready = 0;
1569 			cdtty_rxsoft(sc, p, tp);
1570 		}
1571 
1572 		if (p->p_st_check) {
1573 			p->p_st_check = 0;
1574 			cdtty_stsoft(sc, p, tp);
1575 		}
1576 
1577 		if (p->p_tx_done) {
1578 			p->p_tx_done = 0;
1579 			cdtty_txsoft(sc, p, tp);
1580 		}
1581 	}
1582 }
1583