xref: /netbsd-src/sys/arch/arm/ixp12x0/ixp12x0_com.c (revision bbde328be4e75ea9ad02e9715ea13ca54b797ada)
1 /*	$NetBSD: ixp12x0_com.c,v 1.36 2009/03/14 15:36:02 dsl Exp $ */
2 /*
3  * Copyright (c) 1998, 1999, 2001, 2002 The NetBSD Foundation, Inc.
4  * All rights reserved.
5  *
6  * This code is derived from software contributed to The NetBSD Foundation
7  * by Ichiro FUKUHARA and Naoto Shimazaki.
8  *
9  * This code is derived from software contributed to The NetBSD Foundation
10  * by IWAMOTO Toshihiro.
11  *
12  * This code is derived from software contributed to The NetBSD Foundation
13  * by Charles M. Hannum.
14  *
15  * Redistribution and use in source and binary forms, with or without
16  * modification, are permitted provided that the following conditions
17  * are met:
18  * 1. Redistributions of source code must retain the above copyright
19  *    notice, this list of conditions and the following disclaimer.
20  * 2. Redistributions in binary form must reproduce the above copyright
21  *    notice, this list of conditions and the following disclaimer in the
22  *    documentation and/or other materials provided with the distribution.
23  *
24  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
25  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
26  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
27  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
28  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
29  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
30  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
31  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
32  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
33  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
34  * POSSIBILITY OF SUCH DAMAGE.
35  */
36 
37 /*
38  * Copyright (c) 1991 The Regents of the University of California.
39  * All rights reserved.
40  *
41  * Redistribution and use in source and binary forms, with or without
42  * modification, are permitted provided that the following conditions
43  * are met:
44  * 1. Redistributions of source code must retain the above copyright
45  *    notice, this list of conditions and the following disclaimer.
46  * 2. Redistributions in binary form must reproduce the above copyright
47  *    notice, this list of conditions and the following disclaimer in the
48  *    documentation and/or other materials provided with the distribution.
49  * 3. Neither the name of the University nor the names of its contributors
50  *    may be used to endorse or promote products derived from this software
51  *    without specific prior written permission.
52  *
53  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
54  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
55  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
56  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
57  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
58  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
59  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
60  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
61  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
62  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
63  * SUCH DAMAGE.
64  *
65  *      @(#)com.c       7.5 (Berkeley) 5/16/91
66  */
67 
68 #include <sys/cdefs.h>
69 __KERNEL_RCSID(0, "$NetBSD: ixp12x0_com.c,v 1.36 2009/03/14 15:36:02 dsl Exp $");
70 
71 #include "opt_ddb.h"
72 #include "opt_kgdb.h"
73 
74 #include "rnd.h"
75 #if NRND > 0 && defined(RND_COM)
76 #include <sys/rnd.h>
77 #endif
78 
79 #include <sys/param.h>
80 #include <sys/systm.h>
81 #include <sys/types.h>
82 #include <sys/conf.h>
83 #include <sys/file.h>
84 #include <sys/device.h>
85 #include <sys/kernel.h>
86 #include <sys/malloc.h>
87 #include <sys/tty.h>
88 #include <sys/uio.h>
89 #include <sys/vnode.h>
90 #include <sys/kauth.h>
91 
92 #include <machine/intr.h>
93 #include <machine/bus.h>
94 
95 #include <arm/ixp12x0/ixp12x0_comreg.h>
96 #include <arm/ixp12x0/ixp12x0_comvar.h>
97 #include <arm/ixp12x0/ixp12x0reg.h>
98 #include <arm/ixp12x0/ixp12x0var.h>
99 
100 #include <arm/ixp12x0/ixpsipvar.h>
101 
102 #include <dev/cons.h>
103 #include "ixpcom.h"
104 
105 static int	ixpcomparam(struct tty *, struct termios *);
106 static void	ixpcomstart(struct tty *);
107 static int	ixpcomhwiflow(struct tty *, int);
108 
109 static u_int	cflag2cr(tcflag_t);
110 static void	ixpcom_iflush(struct ixpcom_softc *);
111 static void	ixpcom_set_cr(struct ixpcom_softc *);
112 
113 int             ixpcomcngetc(dev_t);
114 void            ixpcomcnputc(dev_t, int);
115 void            ixpcomcnpollc(dev_t, int);
116 
117 static void	ixpcomsoft(void* arg);
118 inline static void	ixpcom_txsoft(struct ixpcom_softc *, struct tty *);
119 inline static void	ixpcom_rxsoft(struct ixpcom_softc *, struct tty *);
120 
121 void            ixpcomcnprobe(struct consdev *);
122 void            ixpcomcninit(struct consdev *);
123 
124 u_int32_t	ixpcom_cr = 0;		/* tell cr to *_intr.c */
125 u_int32_t	ixpcom_imask = 0;	/* intrrupt mask from *_intr.c */
126 
127 
128 static struct ixpcom_cons_softc {
129 	bus_space_tag_t		sc_iot;
130 	bus_space_handle_t	sc_ioh;
131 	bus_addr_t		sc_baseaddr;
132 	int			sc_ospeed;
133 	tcflag_t		sc_cflag;
134 	int			sc_attached;
135 } ixpcomcn_sc;
136 
137 static struct cnm_state ixpcom_cnm_state;
138 
139 struct ixpcom_softc* ixpcom_sc = NULL;
140 
141 extern struct cfdriver ixpcom_cd;
142 
143 dev_type_open(ixpcomopen);
144 dev_type_close(ixpcomclose);
145 dev_type_read(ixpcomread);
146 dev_type_write(ixpcomwrite);
147 dev_type_ioctl(ixpcomioctl);
148 dev_type_stop(ixpcomstop);
149 dev_type_tty(ixpcomtty);
150 dev_type_poll(ixpcompoll);
151 
152 const struct cdevsw ixpcom_cdevsw = {
153 	ixpcomopen, ixpcomclose, ixpcomread, ixpcomwrite, ixpcomioctl,
154 	ixpcomstop, ixpcomtty, ixpcompoll, nommap, ttykqfilter, D_TTY
155 };
156 
157 struct consdev ixpcomcons = {
158 	NULL, NULL, ixpcomcngetc, ixpcomcnputc, ixpcomcnpollc, NULL,
159 	NULL, NULL, NODEV, CN_NORMAL
160 };
161 
162 #ifndef DEFAULT_COMSPEED
163 #define DEFAULT_COMSPEED 38400
164 #endif
165 
166 #define COMUNIT_MASK    0x7ffff
167 #define COMDIALOUT_MASK 0x80000
168 
169 #define COMUNIT(x)	(minor(x) & COMUNIT_MASK)
170 #define COMDIALOUT(x)	(minor(x) & COMDIALOUT_MASK)
171 
172 #define COM_ISALIVE(sc)	((sc)->enabled != 0 && \
173 			 device_is_active(&(sc)->sc_dev))
174 
175 #define COM_BARRIER(t, h, f) bus_space_barrier((t), (h), 0, COM_NPORTS, (f))
176 
177 #define	COM_LOCK(sc);
178 #define	COM_UNLOCK(sc);
179 
180 #define CFLAGS2CR_MASK	(CR_PE | CR_OES | CR_SBS | CR_DSS | CR_BRD)
181 
182 void
183 ixpcom_attach_subr(struct ixpcom_softc *sc)
184 {
185 	struct tty *tp;
186 
187 	ixpcom_sc = sc;
188 
189 	/* force to use ixpcom0 for console */
190 	if (sc->sc_iot == ixpcomcn_sc.sc_iot
191 	    && sc->sc_baseaddr == ixpcomcn_sc.sc_baseaddr) {
192 		ixpcomcn_sc.sc_attached = 1;
193 		sc->sc_speed = IXPCOMSPEED2BRD(ixpcomcn_sc.sc_ospeed);
194 
195 		/* Make sure the console is always "hardwired". */
196 		/* XXX IXPCOM_SR should be checked  */
197 		delay(10000);	/* wait for output to finish */
198 		SET(sc->sc_hwflags, COM_HW_CONSOLE);
199 		SET(sc->sc_swflags, TIOCFLAG_SOFTCAR);
200 	}
201 
202 	tp = ttymalloc();
203 	tp->t_oproc = ixpcomstart;
204 	tp->t_param = ixpcomparam;
205 	tp->t_hwiflow = ixpcomhwiflow;
206 
207 	sc->sc_tty = tp;
208 	sc->sc_rbuf = malloc(IXPCOM_RING_SIZE << 1, M_DEVBUF, M_NOWAIT);
209 	sc->sc_rbput = sc->sc_rbget = sc->sc_rbuf;
210 	sc->sc_rbavail = IXPCOM_RING_SIZE;
211 	if (sc->sc_rbuf == NULL) {
212 		printf("%s: unable to allocate ring buffer\n",
213 		    sc->sc_dev.dv_xname);
214 		return;
215 	}
216 	sc->sc_ebuf = sc->sc_rbuf + (IXPCOM_RING_SIZE << 1);
217 	sc->sc_tbc = 0;
218 
219 	sc->sc_rie = sc->sc_xie = 0;
220 	ixpcom_cr = IXPCOMSPEED2BRD(DEFAULT_COMSPEED)
221 		| CR_UE | sc->sc_rie | sc->sc_xie | DSS_8BIT;
222 
223 	tty_attach(tp);
224 
225 	if (ISSET(sc->sc_hwflags, COM_HW_CONSOLE)) {
226 		int maj;
227 
228 		/* locate the major number */
229 		maj = cdevsw_lookup_major(&ixpcom_cdevsw);
230 
231 		cn_tab->cn_dev = makedev(maj, device_unit(&sc->sc_dev));
232 
233 		aprint_normal("%s: console\n", sc->sc_dev.dv_xname);
234 	}
235 
236 	sc->sc_si = softint_establish(SOFTINT_SERIAL, ixpcomsoft, sc);
237 
238 #if NRND > 0 && defined(RND_COM)
239 	rnd_attach_source(&sc->rnd_source, sc->sc_dev.dv_xname,
240 			  RND_TYPE_TTY, 0);
241 #endif
242 
243 	/* if there are no enable/disable functions, assume the device
244 	   is always enabled */
245 	if (!sc->enable)
246 		sc->enabled = 1;
247 
248 	/* XXX configure register */
249 	/* xxx_config(sc) */
250 
251 	SET(sc->sc_hwflags, COM_HW_DEV_OK);
252 }
253 
254 static int
255 ixpcomparam(struct tty *tp, struct termios *t)
256 {
257 	struct ixpcom_softc *sc
258 		= device_lookup_private(&ixpcom_cd, COMUNIT(tp->t_dev));
259 	u_int32_t cr;
260 	int s;
261 
262 	if (COM_ISALIVE(sc) == 0)
263 		return (EIO);
264 
265 	cr = IXPCOMSPEED2BRD(t->c_ospeed);
266 
267 	if (t->c_ispeed && t->c_ispeed != t->c_ospeed)
268 		return (EINVAL);
269 
270 	/*
271 	 * For the console, always force CLOCAL and !HUPCL, so that the port
272 	 * is always active.
273 	 */
274 	if (ISSET(sc->sc_swflags, TIOCFLAG_SOFTCAR) ||
275 	    ISSET(sc->sc_hwflags, COM_HW_CONSOLE)) {
276 		SET(t->c_cflag, CLOCAL);
277 		CLR(t->c_cflag, HUPCL);
278 	}
279 
280 	/*
281 	 * If there were no changes, don't do anything.  This avoids dropping
282 	 * input and improves performance when all we did was frob things like
283 	 * VMIN and VTIME.
284 	 */
285 	if (tp->t_ospeed == t->c_ospeed &&
286 	    tp->t_cflag == t->c_cflag)
287 		return (0);
288 
289 	cr |= cflag2cr(t->c_cflag);
290 
291 	s = splserial();
292 	COM_LOCK(sc);
293 
294 	ixpcom_cr = (ixpcom_cr & ~CFLAGS2CR_MASK) | cr;
295 
296 	/*
297 	 * ixpcom don't have any hardware flow control.
298 	 * we skip it.
299 	 */
300 
301 	/* And copy to tty. */
302 	tp->t_ispeed = 0;
303 	tp->t_ospeed = t->c_ospeed;
304 	tp->t_cflag = t->c_cflag;
305 
306 	if (!sc->sc_heldchange) {
307 		if (sc->sc_tx_busy) {
308 			sc->sc_heldtbc = sc->sc_tbc;
309 			sc->sc_tbc = 0;
310 			sc->sc_heldchange = 1;
311 		} else
312 			ixpcom_set_cr(sc);
313 	}
314 
315 	COM_UNLOCK(sc);
316 	splx(s);
317 
318 	/*
319 	 * Update the tty layer's idea of the carrier bit.
320 	 * We tell tty the carrier is always on.
321 	 */
322 	(void) (*tp->t_linesw->l_modem)(tp, 1);
323 
324 #ifdef COM_DEBUG
325 	if (com_debug)
326 		comstatus(sc, "comparam ");
327 #endif
328 
329 	if (!ISSET(t->c_cflag, CHWFLOW)) {
330 		if (sc->sc_tx_stopped) {
331 			sc->sc_tx_stopped = 0;
332 			ixpcomstart(tp);
333 		}
334 	}
335 
336 	return (0);
337 }
338 
339 static int
340 ixpcomhwiflow(struct tty *tp, int block)
341 {
342 	return (0);
343 }
344 
345 static void
346 ixpcom_filltx(struct ixpcom_softc *sc)
347 {
348 	bus_space_tag_t iot = sc->sc_iot;
349 	bus_space_handle_t ioh = sc->sc_ioh;
350 	int n;
351 
352 	n = 0;
353         while (bus_space_read_4(iot, ioh, IXPCOM_SR) & SR_TXR) {
354 		if (n >= sc->sc_tbc)
355 			break;
356 		bus_space_write_4(iot, ioh, IXPCOM_DR,
357 				  0xff & *(sc->sc_tba + n));
358 		n++;
359         }
360         sc->sc_tbc -= n;
361         sc->sc_tba += n;
362 }
363 
364 static void
365 ixpcomstart(struct tty *tp)
366 {
367 	struct ixpcom_softc *sc
368 		= device_lookup_private(&ixpcom_cd, COMUNIT(tp->t_dev));
369 	int s;
370 
371 	if (COM_ISALIVE(sc) == 0)
372 		return;
373 
374 	s = spltty();
375 	if (ISSET(tp->t_state, TS_BUSY | TS_TIMEOUT | TS_TTSTOP))
376 		goto out;
377 	if (sc->sc_tx_stopped)
378 		goto out;
379 
380 	if (!ttypull(tp))
381 		goto out;
382 
383 	/* Grab the first contiguous region of buffer space. */
384 	{
385 		u_char *tba;
386 		int tbc;
387 
388 		tba = tp->t_outq.c_cf;
389 		tbc = ndqb(&tp->t_outq, 0);
390 
391 		(void)splserial();
392 		COM_LOCK(sc);
393 
394 		sc->sc_tba = tba;
395 		sc->sc_tbc = tbc;
396 	}
397 
398 	SET(tp->t_state, TS_BUSY);
399 	sc->sc_tx_busy = 1;
400 
401 	/* Enable transmit completion interrupts if necessary. */
402 	if (!ISSET(sc->sc_xie, CR_XIE)) {
403 		SET(sc->sc_xie, CR_XIE);
404 		ixpcom_set_cr(sc);
405 	}
406 
407 	/* Output the first chunk of the contiguous buffer. */
408 	ixpcom_filltx(sc);
409 
410 	COM_UNLOCK(sc);
411 out:
412 	splx(s);
413 	return;
414 }
415 
416 static void
417 ixpcom_break(struct ixpcom_softc *sc, int onoff)
418 {
419 	if (onoff)
420 		SET(ixpcom_cr, CR_BRK);
421 	else
422 		CLR(ixpcom_cr, CR_BRK);
423 	if (!sc->sc_heldchange) {
424 		if (sc->sc_tx_busy) {
425 			sc->sc_heldtbc = sc->sc_tbc;
426 			sc->sc_tbc = 0;
427 			sc->sc_heldchange = 1;
428 		} else
429 			ixpcom_set_cr(sc);
430 	}
431 }
432 
433 static void
434 ixpcom_shutdown(struct ixpcom_softc *sc)
435 {
436 	int s;
437 
438 	s = splserial();
439 	COM_LOCK(sc);
440 
441 	/* Clear any break condition set with TIOCSBRK. */
442 	ixpcom_break(sc, 0);
443 
444 	/* Turn off interrupts. */
445 	sc->sc_rie = sc->sc_xie = 0;
446 	ixpcom_set_cr(sc);
447 
448 	if (sc->disable) {
449 #ifdef DIAGNOSTIC
450 		if (!sc->enabled)
451 			panic("ixpcom_shutdown: not enabled?");
452 #endif
453 		(*sc->disable)(sc);
454 		sc->enabled = 0;
455 	}
456 	COM_UNLOCK(sc);
457 	splx(s);
458 }
459 
460 int
461 ixpcomopen(dev_t dev, int flag, int mode, struct lwp *l)
462 {
463 	struct ixpcom_softc *sc;
464 	struct tty *tp;
465 	int s, s2;
466 	int error;
467 
468 	sc = device_lookup_private(&ixpcom_cd, COMUNIT(dev));
469 	if (sc == NULL || !ISSET(sc->sc_hwflags, COM_HW_DEV_OK) ||
470 		sc->sc_rbuf == NULL)
471 		return (ENXIO);
472 
473 	if (!device_is_active(&sc->sc_dev))
474 		return (ENXIO);
475 
476 #ifdef KGDB
477 	/*
478 	 * If this is the kgdb port, no other use is permitted.
479 	 */
480 	if (ISSET(sc->sc_hwflags, COM_HW_KGDB))
481 		return (EBUSY);
482 #endif
483 
484 	tp = sc->sc_tty;
485 
486 	if (kauth_authorize_device_tty(l->l_cred, KAUTH_DEVICE_TTY_OPEN, tp))
487 		return (EBUSY);
488 
489 	s = spltty();
490 
491 	/*
492 	 * Do the following iff this is a first open.
493 	 */
494 	if (!ISSET(tp->t_state, TS_ISOPEN) && tp->t_wopen == 0) {
495 		struct termios t;
496 
497 		tp->t_dev = dev;
498 
499 		s2 = splserial();
500 		COM_LOCK(sc);
501 
502 		if (sc->enable) {
503 			if ((*sc->enable)(sc)) {
504 				COM_UNLOCK(sc);
505 				splx(s2);
506 				splx(s);
507 				printf("%s: device enable failed\n",
508 				       sc->sc_dev.dv_xname);
509 				return (EIO);
510 			}
511 			sc->enabled = 1;
512 #if 0
513 /* XXXXXXXXXXXXXXX */
514 			com_config(sc);
515 #endif
516 		}
517 
518 		/* Turn on interrupts. */
519 		SET(sc->sc_rie, CR_RIE);
520 		ixpcom_set_cr(sc);
521 
522 #if 0
523 		/* Fetch the current modem control status, needed later. */
524 		sc->sc_msr = bus_space_read_1(sc->sc_iot, sc->sc_ioh, com_msr);
525 
526 		/* Clear PPS capture state on first open. */
527 		sc->sc_ppsmask = 0;
528 		sc->ppsparam.mode = 0;
529 #endif
530 
531 		COM_UNLOCK(sc);
532 		splx(s2);
533 
534 		/*
535 		 * Initialize the termios status to the defaults.  Add in the
536 		 * sticky bits from TIOCSFLAGS.
537 		 */
538 		t.c_ispeed = 0;
539 		if (ISSET(sc->sc_hwflags, COM_HW_CONSOLE)) {
540 			t.c_ospeed = ixpcomcn_sc.sc_ospeed;
541 			t.c_cflag = ixpcomcn_sc.sc_cflag;
542 		} else {
543 			t.c_ospeed = TTYDEF_SPEED;
544 			t.c_cflag = TTYDEF_CFLAG;
545 		}
546 		if (ISSET(sc->sc_swflags, TIOCFLAG_CLOCAL))
547 			SET(t.c_cflag, CLOCAL);
548 		if (ISSET(sc->sc_swflags, TIOCFLAG_CRTSCTS))
549 			SET(t.c_cflag, CRTSCTS);
550 		if (ISSET(sc->sc_swflags, TIOCFLAG_MDMBUF))
551 			SET(t.c_cflag, MDMBUF);
552 		/* Make sure ixpcomparam() will do something. */
553 		tp->t_ospeed = 0;
554 		(void) ixpcomparam(tp, &t);
555 		tp->t_iflag = TTYDEF_IFLAG;
556 		tp->t_oflag = TTYDEF_OFLAG;
557 		tp->t_lflag = TTYDEF_LFLAG;
558 		ttychars(tp);
559 		ttsetwater(tp);
560 
561 		s2 = splserial();
562 		COM_LOCK(sc);
563 
564 		/* Clear the input ring, and unblock. */
565 		sc->sc_rbput = sc->sc_rbget = sc->sc_rbuf;
566 		sc->sc_rbavail = IXPCOM_RING_SIZE;
567 		ixpcom_iflush(sc);
568 		CLR(sc->sc_rx_flags, RX_ANY_BLOCK);
569 
570 #ifdef COM_DEBUG
571 		if (ixpcom_debug)
572 			comstatus(sc, "ixpcomopen  ");
573 #endif
574 
575 		COM_UNLOCK(sc);
576 		splx(s2);
577 	}
578 
579 	splx(s);
580 
581 	error = ttyopen(tp, COMDIALOUT(dev), ISSET(flag, O_NONBLOCK));
582 	if (error)
583 		goto bad;
584 
585 	error = (*tp->t_linesw->l_open)(dev, tp);
586 	if (error)
587 		goto bad;
588 
589 	return (0);
590 
591 bad:
592 	if (!ISSET(tp->t_state, TS_ISOPEN) && tp->t_wopen == 0) {
593 		/*
594 		 * We failed to open the device, and nobody else had it opened.
595 		 * Clean up the state as appropriate.
596 		 */
597 		ixpcom_shutdown(sc);
598 	}
599 
600 	return (error);
601 }
602 
603 int
604 ixpcomclose(dev_t dev, int flag, int mode, struct lwp *l)
605 {
606 	struct ixpcom_softc *sc = device_lookup_private(&ixpcom_cd, COMUNIT(dev));
607 	struct tty *tp = sc->sc_tty;
608 
609 	/* XXX This is for cons.c. */
610 	if (!ISSET(tp->t_state, TS_ISOPEN))
611 		return (0);
612 
613 	(*tp->t_linesw->l_close)(tp, flag);
614 	ttyclose(tp);
615 
616 	if (COM_ISALIVE(sc) == 0)
617 		return (0);
618 
619 	if (!ISSET(tp->t_state, TS_ISOPEN) && tp->t_wopen == 0) {
620 		/*
621 		 * Although we got a last close, the device may still be in
622 		 * use; e.g. if this was the dialout node, and there are still
623 		 * processes waiting for carrier on the non-dialout node.
624 		 */
625 		ixpcom_shutdown(sc);
626 	}
627 
628 	return (0);
629 }
630 
631 int
632 ixpcomread(dev_t dev, struct uio *uio, int flag)
633 {
634 	struct ixpcom_softc *sc = device_lookup_private(&ixpcom_cd, COMUNIT(dev));
635 	struct tty *tp = sc->sc_tty;
636 
637 	if (COM_ISALIVE(sc) == 0)
638 		return (EIO);
639 
640 	return ((*tp->t_linesw->l_read)(tp, uio, flag));
641 }
642 
643 int
644 ixpcomwrite(dev_t dev, struct uio *uio, int flag)
645 {
646 	struct ixpcom_softc *sc = device_lookup_private(&ixpcom_cd, COMUNIT(dev));
647 	struct tty *tp = sc->sc_tty;
648 
649 	if (COM_ISALIVE(sc) == 0)
650 		return (EIO);
651 
652 	return ((*tp->t_linesw->l_write)(tp, uio, flag));
653 }
654 
655 int
656 ixpcompoll(dev_t dev, int events, struct lwp *l)
657 {
658 	struct ixpcom_softc *sc = device_lookup_private(&ixpcom_cd, COMUNIT(dev));
659 	struct tty *tp = sc->sc_tty;
660 
661 	if (COM_ISALIVE(sc) == 0)
662 		return (EIO);
663 
664 	return ((*tp->t_linesw->l_poll)(tp, events, l));
665 }
666 
667 struct tty *
668 ixpcomtty(dev_t dev)
669 {
670 	struct ixpcom_softc *sc = device_lookup_private(&ixpcom_cd, COMUNIT(dev));
671 	struct tty *tp = sc->sc_tty;
672 
673 	return (tp);
674 }
675 
676 int
677 ixpcomioctl(dev_t dev, u_long cmd, void *data, int flag, struct lwp *l)
678 {
679 	struct ixpcom_softc *sc = device_lookup_private(&ixpcom_cd, COMUNIT(dev));
680 	struct tty *tp = sc->sc_tty;
681 	int error;
682 	int s;
683 
684 	if (COM_ISALIVE(sc) == 0)
685 		return (EIO);
686 
687 	error = (*tp->t_linesw->l_ioctl)(tp, cmd, data, flag, l);
688 	if (error != EPASSTHROUGH)
689 		return (error);
690 
691 	error = ttioctl(tp, cmd, data, flag, l);
692 	if (error != EPASSTHROUGH)
693 		return (error);
694 
695 	error = 0;
696 
697 	s = splserial();
698 	COM_LOCK(sc);
699 
700 	switch (cmd) {
701 	case TIOCSBRK:
702 		ixpcom_break(sc, 1);
703 		break;
704 
705 	case TIOCCBRK:
706 		ixpcom_break(sc, 0);
707 		break;
708 
709 	case TIOCGFLAGS:
710 		*(int *)data = sc->sc_swflags;
711 		break;
712 
713 	case TIOCSFLAGS:
714 		error = kauth_authorize_device_tty(l->l_cred,
715 		    KAUTH_DEVICE_TTY_PRIVSET, tp);
716 		if (error)
717 			break;
718 		sc->sc_swflags = *(int *)data;
719 		break;
720 
721 	default:
722 		error = EPASSTHROUGH;
723 		break;
724 	}
725 
726 	COM_UNLOCK(sc);
727 	splx(s);
728 
729 	return (error);
730 }
731 
732 /*
733  * Stop output on a line.
734  */
735 void
736 ixpcomstop(struct tty *tp, int flag)
737 {
738 	struct ixpcom_softc *sc
739 		= device_lookup_private(&ixpcom_cd, COMUNIT(tp->t_dev));
740 	int s;
741 
742 	s = splserial();
743 	COM_LOCK(sc);
744 	if (ISSET(tp->t_state, TS_BUSY)) {
745 		/* Stop transmitting at the next chunk. */
746 		sc->sc_tbc = 0;
747 		sc->sc_heldtbc = 0;
748 		if (!ISSET(tp->t_state, TS_TTSTOP))
749 			SET(tp->t_state, TS_FLUSH);
750 	}
751 	COM_UNLOCK(sc);
752 	splx(s);
753 }
754 
755 static u_int
756 cflag2cr(tcflag_t cflag)
757 {
758 	u_int cr;
759 
760 	cr  = (cflag & PARENB) ? CR_PE : 0;
761 	cr |= (cflag & PARODD) ? CR_OES : 0;
762 	cr |= (cflag & CSTOPB) ? CR_SBS : 0;
763 	cr |= ((cflag & CSIZE) == CS8) ? DSS_8BIT : 0;
764 
765 	return (cr);
766 }
767 
768 static void
769 ixpcom_iflush(struct ixpcom_softc *sc)
770 {
771 	bus_space_tag_t iot = sc->sc_iot;
772 	bus_space_handle_t ioh = sc->sc_ioh;
773 #ifdef DIAGNOSTIC
774 	int reg;
775 #endif
776 	int timo;
777 
778 #ifdef DIAGNOSTIC
779 	reg = 0xffff;
780 #endif
781 	timo = 50000;
782 	/* flush any pending I/O */
783 	while (ISSET(bus_space_read_4(iot, ioh, IXPCOM_SR), SR_RXR)
784 	       && --timo)
785 #ifdef DIAGNOSTIC
786 		reg =
787 #else
788 			(void)
789 #endif
790 			bus_space_read_4(iot, ioh, IXPCOM_DR);
791 #ifdef DIAGNOSTIC
792 	if (!timo)
793 		printf("%s: com_iflush timeout %02x\n", sc->sc_dev.dv_xname,
794 		       reg);
795 #endif
796 }
797 
798 static void
799 ixpcom_set_cr(struct ixpcom_softc *sc)
800 {
801 	/* XXX */
802 	ixpcom_cr &= ~(CR_RIE | CR_XIE);
803 	ixpcom_cr |= sc->sc_rie | sc->sc_xie;
804 	bus_space_write_4(sc->sc_iot, sc->sc_ioh, IXPCOM_CR,
805 			  ixpcom_cr & ~ixpcom_imask);
806 }
807 
808 int
809 ixpcomcnattach(bus_space_tag_t iot, bus_addr_t iobase, bus_space_handle_t ioh, int ospeed, tcflag_t cflag)
810 {
811 	int cr;
812 
813 	cn_tab = &ixpcomcons;
814 	cn_init_magic(&ixpcom_cnm_state);
815 	/*
816 	 * XXX
817 	 *
818 	 * ixpcom cannot detect a break.  It can only detect framing
819 	 * errors.  And, a sequence of "framing error, framing error"
820 	 * meens a break.  So I made this hack:
821 	 *
822 	 * 1. Set default magic is a sequence of "BREAK, BREAK".
823 	 * 2. Tell cn_check_magic() a "framing error" as BREAK.
824 	 *
825 	 * see ixpcom_intr() too.
826 	 *
827 	 */
828 	/* default magic is a couple of BREAK. */
829 	cn_set_magic("\047\001\047\001");
830 
831 	ixpcomcn_sc.sc_iot = iot;
832 	ixpcomcn_sc.sc_ioh = ioh;
833 	ixpcomcn_sc.sc_baseaddr = iobase;
834 	ixpcomcn_sc.sc_ospeed = ospeed;
835 	ixpcomcn_sc.sc_cflag = cflag;
836 
837 	cr = cflag2cr(cflag);
838 	cr |= IXPCOMSPEED2BRD(ospeed);
839 	cr |= CR_UE;
840 	ixpcom_cr = cr;
841 
842 	/* enable the UART */
843 	bus_space_write_4(iot, iobase, IXPCOM_CR, cr);
844 
845 	return (0);
846 }
847 
848 void
849 ixpcomcnprobe(struct consdev *cp)
850 {
851 	cp->cn_pri = CN_REMOTE;
852 }
853 
854 void
855 ixpcomcnpollc(dev_t dev, int on)
856 {
857 }
858 
859 void
860 ixpcomcnputc(dev_t dev, int c)
861 {
862 	int			s;
863 	bus_space_tag_t		iot = ixpcomcn_sc.sc_iot;
864 	bus_space_handle_t	ioh = ixpcomcn_sc.sc_ioh;
865 
866 	s = splserial();
867 
868 	while(!(bus_space_read_4(iot, ioh, IXPCOM_SR) & SR_TXR))
869 		;
870 
871 	bus_space_write_4(iot, ioh, IXPCOM_DR, c);
872 
873 #ifdef DEBUG
874 	if (c == '\r') {
875 		while(!(bus_space_read_4(iot, ioh, IXPCOM_SR) & SR_TXE))
876 			;
877 	}
878 #endif
879 
880 	splx(s);
881 }
882 
883 int
884 ixpcomcngetc(dev_t dev)
885 {
886 	int			c;
887 	int			s;
888 	bus_space_tag_t		iot = ixpcomcn_sc.sc_iot;
889 	bus_space_handle_t	ioh = ixpcomcn_sc.sc_ioh;
890 
891         s = splserial();
892 
893 	while(!(bus_space_read_4(iot, ioh, IXPCOM_SR) & SR_RXR))
894 		;
895 
896 	c = bus_space_read_4(iot, ioh, IXPCOM_DR);
897 	c &= 0xff;
898 	splx(s);
899 
900 	return (c);
901 }
902 
903 inline static void
904 ixpcom_txsoft(struct ixpcom_softc *sc, struct tty *tp)
905 {
906 	CLR(tp->t_state, TS_BUSY);
907 	if (ISSET(tp->t_state, TS_FLUSH))
908 		CLR(tp->t_state, TS_FLUSH);
909         else
910 		ndflush(&tp->t_outq, (int)(sc->sc_tba - tp->t_outq.c_cf));
911 	(*tp->t_linesw->l_start)(tp);
912 }
913 
914 inline static void
915 ixpcom_rxsoft(struct ixpcom_softc *sc, struct tty *tp)
916 {
917 	int (*rint)(int, struct tty *) = tp->t_linesw->l_rint;
918 	u_char *get, *end;
919 	u_int cc, scc;
920 	u_char lsr;
921 	int code;
922 	int s;
923 
924 	end = sc->sc_ebuf;
925 	get = sc->sc_rbget;
926 	scc = cc = IXPCOM_RING_SIZE - sc->sc_rbavail;
927 #if 0
928 	if (cc == IXPCOM_RING_SIZE) {
929 		sc->sc_floods++;
930 		if (sc->sc_errors++ == 0)
931 			callout_reset(&sc->sc_diag_callout, 60 * hz,
932 			    comdiag, sc);
933 	}
934 #endif
935 	while (cc) {
936 		code = get[0];
937 		lsr = get[1];
938 		if (ISSET(lsr, DR_ROR | DR_FRE | DR_PRE)) {
939 #if 0
940 			if (ISSET(lsr, DR_ROR)) {
941 				sc->sc_overflows++;
942 				if (sc->sc_errors++ == 0)
943 					callout_reset(&sc->sc_diag_callout,
944 					    60 * hz, comdiag, sc);
945 			}
946 #endif
947 			if (ISSET(lsr, DR_FRE))
948 				SET(code, TTY_FE);
949 			if (ISSET(lsr, DR_PRE))
950 				SET(code, TTY_PE);
951 		}
952 		if ((*rint)(code, tp) == -1) {
953 			/*
954 			 * The line discipline's buffer is out of space.
955 			 */
956 			if (!ISSET(sc->sc_rx_flags, RX_TTY_BLOCKED)) {
957 				/*
958 				 * We're either not using flow control, or the
959 				 * line discipline didn't tell us to block for
960 				 * some reason.  Either way, we have no way to
961 				 * know when there's more space available, so
962 				 * just drop the rest of the data.
963 				 */
964 				get += cc << 1;
965 				if (get >= end)
966 					get -= IXPCOM_RING_SIZE << 1;
967 				cc = 0;
968 			} else {
969 				/*
970 				 * Don't schedule any more receive processing
971 				 * until the line discipline tells us there's
972 				 * space available (through comhwiflow()).
973 				 * Leave the rest of the data in the input
974 				 * buffer.
975 				 */
976 				SET(sc->sc_rx_flags, RX_TTY_OVERFLOWED);
977 			}
978 			break;
979 		}
980 		get += 2;
981 		if (get >= end)
982 			get = sc->sc_rbuf;
983 		cc--;
984 	}
985 
986 	if (cc != scc) {
987 		sc->sc_rbget = get;
988 		s = splserial();
989 		COM_LOCK(sc);
990 
991 		cc = sc->sc_rbavail += scc - cc;
992 		/* Buffers should be ok again, release possible block. */
993 		if (cc >= 1) {
994 			if (ISSET(sc->sc_rx_flags, RX_IBUF_OVERFLOWED)) {
995 				CLR(sc->sc_rx_flags, RX_IBUF_OVERFLOWED);
996 				SET(sc->sc_rie, CR_RIE);
997 				ixpcom_set_cr(sc);
998 			}
999 			if (ISSET(sc->sc_rx_flags, RX_IBUF_BLOCKED)) {
1000 				CLR(sc->sc_rx_flags, RX_IBUF_BLOCKED);
1001 #if 0
1002 				com_hwiflow(sc);
1003 #endif
1004 			}
1005 		}
1006 		COM_UNLOCK(sc);
1007 		splx(s);
1008 	}
1009 }
1010 
1011 static void
1012 ixpcomsoft(void* arg)
1013 {
1014 	struct ixpcom_softc *sc = arg;
1015 
1016 	if (COM_ISALIVE(sc) == 0)
1017 		return;
1018 
1019 	if (sc->sc_rx_ready) {
1020 		sc->sc_rx_ready = 0;
1021 		ixpcom_rxsoft(sc, sc->sc_tty);
1022 	}
1023 	if (sc->sc_tx_done) {
1024 		sc->sc_tx_done = 0;
1025 		ixpcom_txsoft(sc, sc->sc_tty);
1026 	}
1027 }
1028 
1029 int
1030 ixpcomintr(void* arg)
1031 {
1032 	struct ixpcom_softc *sc = arg;
1033 	bus_space_tag_t iot = sc->sc_iot;
1034 	bus_space_handle_t ioh = sc->sc_ioh;
1035 	u_char *put, *end;
1036 	u_int cc;
1037 	u_int cr;
1038 	u_int sr;
1039 	u_int32_t c;
1040 
1041 	if (COM_ISALIVE(sc) == 0)
1042 		return (0);
1043 
1044 	COM_LOCK(sc);
1045 	cr = bus_space_read_4(iot, ioh, IXPCOM_CR) & CR_UE;
1046 
1047 	if (!cr) {
1048 		COM_UNLOCK(sc);
1049 		return (0);
1050 	}
1051 
1052 	sr = bus_space_read_4(iot, ioh, IXPCOM_SR);
1053 	if (!ISSET(sr, SR_TXR | SR_RXR))
1054 		return (0);
1055 
1056 	/*
1057 	 * XXX
1058 	 *
1059 	 * ixpcom cannot detect a break.  It can only detect framing
1060 	 * errors.  And, a sequence of "framing error, framing error"
1061 	 * meens a break.  So I made this hack:
1062 	 *
1063 	 * 1. Set default magic is a sequence of "BREAK, BREAK".
1064 	 * 2. Tell cn_check_magic() a "framing error" as BREAK.
1065 	 *
1066 	 * see ixpcomcnattach() too.
1067 	 *
1068 	 */
1069 	if (ISSET(sr, SR_FRE)) {
1070 		cn_check_magic(sc->sc_tty->t_dev,
1071 			       CNC_BREAK, ixpcom_cnm_state);
1072 	}
1073 
1074 	end = sc->sc_ebuf;
1075 	put = sc->sc_rbput;
1076 	cc = sc->sc_rbavail;
1077 
1078 	if (ISSET(sr, SR_RXR)) {
1079 		if (!ISSET(sc->sc_rx_flags, RX_IBUF_OVERFLOWED)) {
1080 			while (cc > 0) {
1081 				if (!ISSET(sr, SR_RXR))
1082 					break;
1083 				c = bus_space_read_4(iot, ioh, IXPCOM_DR);
1084 				if (ISSET(c, DR_FRE)) {
1085 					cn_check_magic(sc->sc_tty->t_dev,
1086 						       CNC_BREAK,
1087 						       ixpcom_cnm_state);
1088 				}
1089 				put[0] = c & 0xff;
1090 				put[1] = (c >> 8) & 0xff;
1091 				cn_check_magic(sc->sc_tty->t_dev,
1092 					       put[0], ixpcom_cnm_state);
1093 				put += 2;
1094 				if (put >= end)
1095 					put = sc->sc_rbuf;
1096 				cc--;
1097 
1098 				sr = bus_space_read_4(iot, ioh, IXPCOM_SR);
1099 			}
1100 
1101 			/*
1102 			 * Current string of incoming characters ended because
1103 			 * no more data was available or we ran out of space.
1104 			 * Schedule a receive event if any data was received.
1105 			 * If we're out of space, turn off receive interrupts.
1106 			 */
1107 			sc->sc_rbput = put;
1108 			sc->sc_rbavail = cc;
1109 			if (!ISSET(sc->sc_rx_flags, RX_TTY_OVERFLOWED))
1110 				sc->sc_rx_ready = 1;
1111 
1112 			/*
1113 			 * See if we are in danger of overflowing a buffer. If
1114 			 * so, use hardware flow control to ease the pressure.
1115 			 */
1116 
1117 			/* but ixpcom cannot. X-( */
1118 
1119 			/*
1120 			 * If we're out of space, disable receive interrupts
1121 			 * until the queue has drained a bit.
1122 			 */
1123 			if (!cc) {
1124 				SET(sc->sc_rx_flags, RX_IBUF_OVERFLOWED);
1125 				CLR(sc->sc_rie, CR_RIE);
1126 				ixpcom_set_cr(sc);
1127 			}
1128 		} else {
1129 #ifdef DIAGNOSTIC
1130 			panic("ixpcomintr: we shouldn't reach here");
1131 #endif
1132 			CLR(sc->sc_rie, CR_RIE);
1133 			ixpcom_set_cr(sc);
1134 		}
1135 	}
1136 
1137 	/*
1138 	 * Done handling any receive interrupts. See if data can be
1139 	 * transmitted as well. Schedule tx done event if no data left
1140 	 * and tty was marked busy.
1141 	 */
1142 	sr = bus_space_read_4(iot, ioh, IXPCOM_SR);
1143 	if (ISSET(sr, SR_TXR)) {
1144 		/*
1145 		 * If we've delayed a parameter change, do it now, and restart
1146 		 * output.
1147 		 */
1148 		if (sc->sc_heldchange) {
1149 			ixpcom_set_cr(sc);
1150 			sc->sc_heldchange = 0;
1151 			sc->sc_tbc = sc->sc_heldtbc;
1152 			sc->sc_heldtbc = 0;
1153 		}
1154 
1155 		/* Output the next chunk of the contiguous buffer, if any. */
1156 		if (sc->sc_tbc > 0) {
1157 			ixpcom_filltx(sc);
1158 		} else {
1159 			/* Disable transmit completion interrupts if necessary. */
1160 			if (ISSET(sc->sc_xie, CR_XIE)) {
1161 				CLR(sc->sc_xie, CR_XIE);
1162 				ixpcom_set_cr(sc);
1163 			}
1164 			if (sc->sc_tx_busy) {
1165 				sc->sc_tx_busy = 0;
1166 				sc->sc_tx_done = 1;
1167 			}
1168 		}
1169 	}
1170 	COM_UNLOCK(sc);
1171 
1172 	/* Wake up the poller. */
1173 	softint_schedule(sc->sc_si);
1174 
1175 #if NRND > 0 && defined(RND_COM)
1176 	rnd_add_uint32(&sc->rnd_source, iir | lsr);
1177 #endif
1178 	return (1);
1179 }
1180