xref: /netbsd/sys/arch/arm/sa11x0/sa11x0_com.c (revision 6550d01e)
1 /*      $NetBSD: sa11x0_com.c,v 1.47 2010/08/19 15:17:53 tsutsui Exp $        */
2 
3 /*-
4  * Copyright (c) 1998, 1999, 2001 The NetBSD Foundation, Inc.
5  * All rights reserved.
6  *
7  * This code is derived from software contributed to The NetBSD Foundation
8  * by IWAMOTO Toshihiro.
9  *
10  * This code is derived from software contributed to The NetBSD Foundation
11  * by Charles M. Hannum.
12  *
13  * Redistribution and use in source and binary forms, with or without
14  * modification, are permitted provided that the following conditions
15  * are met:
16  * 1. Redistributions of source code must retain the above copyright
17  *    notice, this list of conditions and the following disclaimer.
18  * 2. Redistributions in binary form must reproduce the above copyright
19  *    notice, this list of conditions and the following disclaimer in the
20  *    documentation and/or other materials provided with the distribution.
21  *
22  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
23  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
24  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
25  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
26  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
27  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
28  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
29  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
30  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
31  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
32  * POSSIBILITY OF SUCH DAMAGE.
33  */
34 
35 /*
36  * Copyright (c) 1991 The Regents of the University of California.
37  * All rights reserved.
38  *
39  * Redistribution and use in source and binary forms, with or without
40  * modification, are permitted provided that the following conditions
41  * are met:
42  * 1. Redistributions of source code must retain the above copyright
43  *    notice, this list of conditions and the following disclaimer.
44  * 2. Redistributions in binary form must reproduce the above copyright
45  *    notice, this list of conditions and the following disclaimer in the
46  *    documentation and/or other materials provided with the distribution.
47  * 3. Neither the name of the University nor the names of its contributors
48  *    may be used to endorse or promote products derived from this software
49  *    without specific prior written permission.
50  *
51  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
52  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
53  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
54  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
55  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
56  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
57  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
58  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
59  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
60  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
61  * SUCH DAMAGE.
62  *
63  *	@(#)com.c	7.5 (Berkeley) 5/16/91
64  */
65 
66 #include <sys/cdefs.h>
67 __KERNEL_RCSID(0, "$NetBSD: sa11x0_com.c,v 1.47 2010/08/19 15:17:53 tsutsui Exp $");
68 
69 #include "opt_com.h"
70 #include "opt_ddb.h"
71 #include "opt_ddbparam.h"
72 #include "opt_kgdb.h"
73 #include "opt_multiprocessor.h"
74 #include "opt_lockdebug.h"
75 
76 #include "rnd.h"
77 #if NRND > 0 && defined(RND_COM)
78 #include <sys/rnd.h>
79 #endif
80 
81 #include <sys/param.h>
82 #include <sys/systm.h>
83 #include <sys/types.h>
84 #include <sys/conf.h>
85 #include <sys/file.h>
86 #include <sys/device.h>
87 #include <sys/kernel.h>
88 #include <sys/malloc.h>
89 #include <sys/tty.h>
90 #include <sys/uio.h>
91 #include <sys/vnode.h>
92 #include <sys/kauth.h>
93 
94 #include <dev/cons.h>
95 
96 #include <machine/bus.h>
97 #include <arm/sa11x0/sa11x0_reg.h>
98 #include <arm/sa11x0/sa11x0_var.h>
99 #include <arm/sa11x0/sa11x0_comreg.h>
100 #include <arm/sa11x0/sa11x0_comvar.h>
101 #include <arm/sa11x0/sa11x0_gpioreg.h>
102 
103 #ifdef hpcarm
104 #include <hpc/include/platid.h>
105 #include <hpc/include/platid_mask.h>
106 #endif
107 
108 #include "sacom.h"
109 
110 dev_type_open(sacomopen);
111 dev_type_close(sacomclose);
112 dev_type_read(sacomread);
113 dev_type_write(sacomwrite);
114 dev_type_ioctl(sacomioctl);
115 dev_type_stop(sacomstop);
116 dev_type_tty(sacomtty);
117 dev_type_poll(sacompoll);
118 
119 const struct cdevsw sacom_cdevsw = {
120 	sacomopen, sacomclose, sacomread, sacomwrite, sacomioctl,
121 	sacomstop, sacomtty, sacompoll, nommap, ttykqfilter, D_TTY
122 };
123 
124 static	int	sacom_match(device_t, cfdata_t, void *);
125 static	void	sacom_attach(device_t, device_t, void *);
126 static	void	sacom_filltx(struct sacom_softc *);
127 static	void	sacom_attach_subr(struct sacom_softc *);
128 #if defined(DDB) || defined(KGDB)
129 static	void	sacom_enable_debugport(struct sacom_softc *);
130 #endif
131 int		sacom_detach(device_t, int);
132 void		sacom_config(struct sacom_softc *);
133 int		sacom_activate(device_t, enum devact);
134 void		sacom_shutdown(struct sacom_softc *);
135 static	u_int	cflag2cr0(tcflag_t);
136 int		sacomparam(struct tty *, struct termios *);
137 void		sacomstart(struct tty *);
138 int		sacomhwiflow(struct tty *, int);
139 
140 void		sacom_loadchannelregs(struct sacom_softc *);
141 void		sacom_hwiflow(struct sacom_softc *);
142 void		sacom_break(struct sacom_softc *, int);
143 void		sacom_modem(struct sacom_softc *, int);
144 void		tiocm_to_sacom(struct sacom_softc *, u_long, int);
145 int		sacom_to_tiocm(struct sacom_softc *);
146 void		sacom_iflush(struct sacom_softc *);
147 
148 int		sacominit(bus_space_tag_t, bus_addr_t, int, tcflag_t,
149 			  bus_space_handle_t *);
150 int		sacom_is_console(bus_space_tag_t, bus_addr_t,
151 				 bus_space_handle_t *);
152 
153 void 		sacomsoft(void *);
154 
155 static inline void sacom_rxsoft(struct sacom_softc *, struct tty *);
156 static inline void sacom_txsoft(struct sacom_softc *, struct tty *);
157 static inline void sacom_stsoft(struct sacom_softc *, struct tty *);
158 static inline void sacom_schedrx(struct sacom_softc *);
159 
160 #ifdef hpcarm
161 /* HPCARM specific functions */
162 static void	sacom_j720_init(device_t, device_t);
163 #endif
164 
165 #define COMUNIT_MASK	0x7ffff
166 #define COMDIALOUT_MASK	0x80000
167 
168 #define COMUNIT(x)	(minor(x) & COMUNIT_MASK)
169 #define COMDIALOUT(x)	(minor(x) & COMDIALOUT_MASK)
170 
171 #define COM_ISALIVE(sc)	((sc)->enabled != 0 && \
172 			 device_is_active((sc)->sc_dev))
173 
174 #define COM_BARRIER(t, h, f) bus_space_barrier((t), (h), 0, COM_NPORTS, (f))
175 #define COM_LOCK(sc)
176 #define COM_UNLOCK(sc)
177 
178 int		sacomintr(void *);
179 int		sacomcngetc(dev_t);
180 void		sacomcnputc(dev_t, int);
181 void		sacomcnpollc(dev_t, int);
182 
183 void		sacomcnprobe(struct consdev *);
184 void		sacomcninit(struct consdev *);
185 
186 extern struct bus_space sa11x0_bs_tag;
187 
188 static bus_space_tag_t sacomconstag;
189 static bus_space_handle_t sacomconsioh;
190 static bus_addr_t sacomconsaddr = SACOM3_BASE; /* XXX */
191 
192 static int sacomconsattached;
193 static int sacomconsrate;
194 static tcflag_t sacomconscflag;
195 
196 CFATTACH_DECL_NEW(sacom, sizeof(struct sacom_softc),
197     sacom_match, sacom_attach, NULL, NULL);
198 extern struct cfdriver sacom_cd;
199 
200 #ifdef hpcarm
201 struct platid_data sacom_platid_table[] = {
202 	{ &platid_mask_MACH_HP_JORNADA_7XX, sacom_j720_init },
203 	{ NULL, NULL }
204 };
205 #endif
206 
207 struct consdev sacomcons = {
208 	NULL, NULL, sacomcngetc, sacomcnputc, sacomcnpollc, NULL,
209 	NULL, NULL, NODEV, CN_NORMAL
210 };
211 
212 #ifndef CONMODE
213 #define CONMODE ((TTYDEF_CFLAG & ~(CSIZE | CSTOPB | PARENB)) | CS8) /* 8N1 */
214 #endif
215 #ifndef CONSPEED
216 #define CONSPEED 9600
217 #endif
218 #ifndef CONADDR
219 #define CONADDR SACOM3_BASE
220 #endif
221 
222 static int
223 sacom_match(device_t parent, cfdata_t match, void *aux)
224 {
225 
226 	return 1;
227 }
228 
229 void
230 sacom_attach(device_t parent, device_t self, void *aux)
231 {
232 	struct sacom_softc *sc = device_private(self);
233 	struct sa11x0_attach_args *sa = aux;
234 
235 #ifdef hpcarm
236 	struct platid_data *p;
237 	void (*mdinit)(device_t, device_t);
238 #endif
239 
240 	aprint_normal("\n");
241 
242 	sc->sc_dev = self;
243 	sc->sc_iot = sa->sa_iot;
244 	sc->sc_baseaddr = sa->sa_addr;
245 
246 	if (bus_space_map(sa->sa_iot, sa->sa_addr, sa->sa_size, 0,
247 	    &sc->sc_ioh)) {
248 		aprint_normal_dev(self, "unable to map registers\n");
249 		return;
250 	}
251 
252 	switch (sc->sc_baseaddr) {
253 	case SACOM1_BASE:
254 		aprint_normal_dev(self, "SA-11x0 UART1\n");
255 		break;
256 	case SACOM2_BASE:
257 		aprint_normal_dev(self, "SA-11x0 UART2 (IRDA)\n");
258 		break;
259 	case SACOM3_BASE:
260 		aprint_normal_dev(self, "SA-11x0 UART3\n");
261 		break;
262 	default:
263 		aprint_normal_dev(self, "unknown SA-11x0 UART\n");
264 		break;
265 	}
266 
267 	sacom_attach_subr(sc);
268 
269 #ifdef hpcarm
270 	/* Do hpcarm specific initialization, if any */
271 	if ((p = platid_search_data(&platid, sacom_platid_table)) != NULL) {
272 		mdinit = p->data;
273 		(*mdinit)(parent, self);
274 	}
275 #endif
276 
277 	sa11x0_intr_establish(0, sa->sa_intr, 1, IPL_SERIAL, sacomintr, sc);
278 }
279 
280 void
281 sacom_attach_subr(struct sacom_softc *sc)
282 {
283 	bus_addr_t iobase = sc->sc_baseaddr;
284 	bus_space_tag_t iot = sc->sc_iot;
285 	struct tty *tp;
286 
287 	/* XXX Do we need to disable interrupts here? */
288 
289 	if (iot == sacomconstag && iobase == sacomconsaddr) {
290 		sacomconsattached = 1;
291 		sc->sc_speed = SACOMSPEED(sacomconsrate);
292 
293 		/* Make sure the console is always "hardwired". */
294 		delay(10000);			/* wait for output to finish */
295 		SET(sc->sc_hwflags, COM_HW_CONSOLE);
296 		SET(sc->sc_swflags, TIOCFLAG_SOFTCAR);
297 	}
298 
299 	tp = ttymalloc();
300 	tp->t_oproc = sacomstart;
301 	tp->t_param = sacomparam;
302 	tp->t_hwiflow = sacomhwiflow;
303 
304 	sc->sc_tty = tp;
305 	sc->sc_rbuf = malloc(SACOM_RING_SIZE << 1, M_DEVBUF, M_NOWAIT);
306 	sc->sc_rbput = sc->sc_rbget = sc->sc_rbuf;
307 	sc->sc_rbavail = SACOM_RING_SIZE;
308 	if (sc->sc_rbuf == NULL) {
309 		aprint_normal_dev(sc->sc_dev, "unable to allocate ring buffer\n");
310 		return;
311 	}
312 	sc->sc_ebuf = sc->sc_rbuf + (SACOM_RING_SIZE << 1);
313 	sc->sc_tbc = 0;
314 
315 	tty_attach(tp);
316 
317 	if (ISSET(sc->sc_hwflags, COM_HW_CONSOLE)) {
318 		int maj;
319 
320 		/* locate the major number */
321 		maj = cdevsw_lookup_major(&sacom_cdevsw);
322 
323 		cn_tab->cn_dev = makedev(maj, device_unit(sc->sc_dev));
324 
325 		delay(10000); /* XXX */
326 		aprint_normal_dev(sc->sc_dev, "console\n");
327 		delay(10000); /* XXX */
328 	}
329 
330 
331 	sc->sc_si = softint_establish(SOFTINT_SERIAL, sacomsoft, sc);
332 
333 #if NRND > 0 && defined(RND_COM)
334 	rnd_attach_source(&sc->rnd_source, device_xname(sc->sc_dev),
335 			  RND_TYPE_TTY, 0);
336 #endif
337 
338 	/* if there are no enable/disable functions, assume the device
339 	   is always enabled */
340 	if (!sc->enable)
341 		sc->enabled = 1;
342 
343 	sacom_config(sc);
344 
345 	SET(sc->sc_hwflags, COM_HW_DEV_OK);
346 }
347 
348 /* This is necessary when dynamically changing SAIP configuration. */
349 int
350 sacom_detach(device_t dev, int flags)
351 {
352 	struct sacom_softc *sc = device_private(dev);
353 	int maj, mn;
354 
355 	if (sc->sc_hwflags & (COM_HW_CONSOLE|COM_HW_KGDB))
356 		return EBUSY;
357 
358 	if (sc->disable != NULL && sc->enabled != 0) {
359 		(*sc->disable)(sc);
360 		sc->enabled = 0;
361 	}
362 
363 	/* locate the major number */
364 	maj = cdevsw_lookup_major(&sacom_cdevsw);
365 
366 	/* Nuke the vnodes for any open instances. */
367 	mn = device_unit(dev);
368 	vdevgone(maj, mn, mn, VCHR);
369 
370 	mn |= COMDIALOUT_MASK;
371 	vdevgone(maj, mn, mn, VCHR);
372 
373 	/* Free the receive buffer. */
374 	free(sc->sc_rbuf, M_DEVBUF);
375 
376 	/* Detach and free the tty. */
377 	tty_detach(sc->sc_tty);
378 	ttyfree(sc->sc_tty);
379 
380 	/* Unhook the soft interrupt handler. */
381 	softint_disestablish(sc->sc_si);
382 
383 #if NRND > 0 && defined(RND_COM)
384 	/* Unhook the entropy source. */
385 	rnd_detach_source(&sc->rnd_source);
386 #endif
387 
388 	return 0;
389 }
390 
391 void
392 sacom_config(struct sacom_softc *sc)
393 {
394 	bus_space_tag_t iot = sc->sc_iot;
395 	bus_space_handle_t ioh = sc->sc_ioh;
396 
397 	/* Disable engine before configuring the device. */
398 	sc->sc_cr3 = 0;
399 	bus_space_write_4(iot, ioh, SACOM_CR3, sc->sc_cr3);
400 
401 #ifdef DDB
402 	if (ISSET(sc->sc_hwflags, COM_HW_CONSOLE))
403 		sacom_enable_debugport(sc);
404 #endif
405 }
406 
407 #ifdef DDB
408 static void
409 sacom_enable_debugport(struct sacom_softc *sc)
410 {
411 	bus_space_tag_t iot = sc->sc_iot;
412 	bus_space_handle_t ioh = sc->sc_ioh;
413 	int s;
414 
415 	s = splserial();
416 	COM_LOCK(sc);
417 	sc->sc_cr3 = CR3_RXE | CR3_TXE;
418 	bus_space_write_4(iot, ioh, SACOM_CR3, sc->sc_cr3);
419 	COM_UNLOCK(sc);
420 	splx(s);
421 }
422 #endif
423 
424 int
425 sacom_activate(device_t dev, enum devact act)
426 {
427 	struct sacom_softc *sc = device_private(dev);
428 
429 	switch (act) {
430 	case DVACT_DEACTIVATE:
431 		sc->enabled = 0;
432 		return 0;
433 	default:
434 		return EOPNOTSUPP;
435 	}
436 }
437 
438 void
439 sacom_shutdown(struct sacom_softc *sc)
440 {
441 	struct tty *tp = sc->sc_tty;
442 	int s;
443 
444 	s = splserial();
445 	COM_LOCK(sc);
446 
447 	/* Clear any break condition set with TIOCSBRK. */
448 	sacom_break(sc, 0);
449 
450 	/*
451 	 * Hang up if necessary.  Wait a bit, so the other side has time to
452 	 * notice even if we immediately open the port again.
453 	 * Avoid tsleeping above splhigh().
454 	 */
455 	if (ISSET(tp->t_cflag, HUPCL)) {
456 		sacom_modem(sc, 0);
457 		COM_UNLOCK(sc);
458 		splx(s);
459 		/* XXX tsleep will only timeout */
460 		(void) tsleep(sc, TTIPRI, ttclos, hz);
461 		s = splserial();
462 		COM_LOCK(sc);
463 	}
464 
465 	/* Turn off interrupts. */
466 	sc->sc_cr3 = 0;
467 	bus_space_write_4(sc->sc_iot, sc->sc_ioh, SACOM_CR3, sc->sc_cr3);
468 
469 	if (sc->disable) {
470 #ifdef DIAGNOSTIC
471 		if (!sc->enabled)
472 			panic("sacom_shutdown: not enabled?");
473 #endif
474 		(*sc->disable)(sc);
475 		sc->enabled = 0;
476 	}
477 	COM_UNLOCK(sc);
478 	splx(s);
479 }
480 
481 int
482 sacomopen(dev_t dev, int flag, int mode, struct lwp *l)
483 {
484 	struct sacom_softc *sc;
485 	struct tty *tp;
486 	int s, s2;
487 	int error;
488 
489 	sc = device_lookup_private(&sacom_cd, COMUNIT(dev));
490 	if (sc == NULL || !ISSET(sc->sc_hwflags, COM_HW_DEV_OK) ||
491 		sc->sc_rbuf == NULL)
492 		return ENXIO;
493 
494 	if (!device_is_active(sc->sc_dev))
495 		return ENXIO;
496 
497 	tp = sc->sc_tty;
498 
499 	if (kauth_authorize_device_tty(l->l_cred, KAUTH_DEVICE_TTY_OPEN, tp))
500 		return (EBUSY);
501 
502 	s = spltty();
503 
504 	/*
505 	 * Do the following iff this is a first open.
506 	 */
507 	if (!ISSET(tp->t_state, TS_ISOPEN) && tp->t_wopen == 0) {
508 		struct termios t;
509 
510 		tp->t_dev = dev;
511 
512 		s2 = splserial();
513 		COM_LOCK(sc);
514 
515 		if (sc->enable) {
516 			if ((*sc->enable)(sc)) {
517 				COM_UNLOCK(sc);
518 				splx(s2);
519 				splx(s);
520 				aprint_normal_dev(sc->sc_dev, "device enable failed\n");
521 				return EIO;
522 			}
523 			sc->enabled = 1;
524 			sacom_config(sc);
525 		}
526 
527 		/* Turn on interrupts. */
528 		sc->sc_cr3 = CR3_RXE | CR3_TXE | CR3_RIE | CR3_TIE;
529 		bus_space_write_4(sc->sc_iot, sc->sc_ioh, SACOM_CR3,
530 				  sc->sc_cr3);
531 
532 
533 		COM_UNLOCK(sc);
534 		splx(s2);
535 
536 		/*
537 		 * Initialize the termios status to the defaults.  Add in the
538 		 * sticky bits from TIOCSFLAGS.
539 		 */
540 		t.c_ispeed = 0;
541 		if (ISSET(sc->sc_hwflags, COM_HW_CONSOLE)) {
542 			t.c_ospeed = sacomconsrate;
543 			t.c_cflag = sacomconscflag;
544 		} else {
545 			t.c_ospeed = TTYDEF_SPEED;
546 			t.c_cflag = TTYDEF_CFLAG;
547 		}
548 		if (ISSET(sc->sc_swflags, TIOCFLAG_CLOCAL))
549 			SET(t.c_cflag, CLOCAL);
550 		if (ISSET(sc->sc_swflags, TIOCFLAG_CRTSCTS))
551 			SET(t.c_cflag, CRTSCTS);
552 		if (ISSET(sc->sc_swflags, TIOCFLAG_MDMBUF))
553 			SET(t.c_cflag, MDMBUF);
554 		/* Make sure sacomparam() will do something. */
555 		tp->t_ospeed = 0;
556 		(void) sacomparam(tp, &t);
557 		tp->t_iflag = TTYDEF_IFLAG;
558 		tp->t_oflag = TTYDEF_OFLAG;
559 		tp->t_lflag = TTYDEF_LFLAG;
560 		ttychars(tp);
561 		ttsetwater(tp);
562 
563 		s2 = splserial();
564 		COM_LOCK(sc);
565 
566 		/*
567 		 * Turn on DTR.  We must always do this, even if carrier is not
568 		 * present, because otherwise we'd have to use TIOCSDTR
569 		 * immediately after setting CLOCAL, which applications do not
570 		 * expect.  We always assert DTR while the device is open
571 		 * unless explicitly requested to deassert it.
572 		 */
573 		sacom_modem(sc, 1);
574 
575 		/* Clear the input ring, and unblock. */
576 		sc->sc_rbput = sc->sc_rbget = sc->sc_rbuf;
577 		sc->sc_rbavail = SACOM_RING_SIZE;
578 		sacom_iflush(sc);
579 		CLR(sc->sc_rx_flags, RX_ANY_BLOCK);
580 		sacom_hwiflow(sc);
581 
582 #ifdef COM_DEBUG
583 		if (sacom_debug)
584 			comstatus(sc, "sacomopen  ");
585 #endif
586 
587 		COM_UNLOCK(sc);
588 		splx(s2);
589 	}
590 
591 	splx(s);
592 
593 	error = ttyopen(tp, COMDIALOUT(dev), ISSET(flag, O_NONBLOCK));
594 	if (error)
595 		goto bad;
596 
597 	error = (*tp->t_linesw->l_open)(dev, tp);
598 	if (error)
599 		goto bad;
600 
601 	return 0;
602 
603 bad:
604 	if (!ISSET(tp->t_state, TS_ISOPEN) && tp->t_wopen == 0) {
605 		/*
606 		 * We failed to open the device, and nobody else had it opened.
607 		 * Clean up the state as appropriate.
608 		 */
609 		sacom_shutdown(sc);
610 	}
611 
612 	return error;
613 }
614 
615 int
616 sacomclose(dev_t dev, int flag, int mode, struct lwp *l)
617 {
618 	struct sacom_softc *sc =
619 		device_lookup_private(&sacom_cd, COMUNIT(dev));
620 	struct tty *tp = sc->sc_tty;
621 
622 	/* XXX This is for cons.c. */
623 	if (!ISSET(tp->t_state, TS_ISOPEN))
624 		return 0;
625 
626 	(*tp->t_linesw->l_close)(tp, flag);
627 	ttyclose(tp);
628 
629 	if (COM_ISALIVE(sc) == 0)
630 		return 0;
631 
632 	if (!ISSET(tp->t_state, TS_ISOPEN) && tp->t_wopen == 0) {
633 		/*
634 		 * Although we got a last close, the device may still be in
635 		 * use; e.g. if this was the dialout node, and there are still
636 		 * processes waiting for carrier on the non-dialout node.
637 		 */
638 		sacom_shutdown(sc);
639 	}
640 
641 	return 0;
642 }
643 
644 int
645 sacomread(dev_t dev, struct uio *uio, int flag)
646 {
647 	struct sacom_softc *sc =
648 		device_lookup_private(&sacom_cd, COMUNIT(dev));
649 	struct tty *tp = sc->sc_tty;
650 
651 	if (COM_ISALIVE(sc) == 0)
652 		return EIO;
653 
654 	return (*tp->t_linesw->l_read)(tp, uio, flag);
655 }
656 
657 int
658 sacomwrite(dev_t dev, struct uio *uio, int flag)
659 {
660 	struct sacom_softc *sc =
661 		device_lookup_private(&sacom_cd, COMUNIT(dev));
662 	struct tty *tp = sc->sc_tty;
663 
664 	if (COM_ISALIVE(sc) == 0)
665 		return EIO;
666 
667 	return (*tp->t_linesw->l_write)(tp, uio, flag);
668 }
669 
670 int
671 sacompoll(dev_t dev, int events, struct lwp *l)
672 {
673 	struct sacom_softc *sc =
674 		device_lookup_private(&sacom_cd, COMUNIT(dev));
675 	struct tty *tp = sc->sc_tty;
676 
677 	if (COM_ISALIVE(sc) == 0)
678 		return EIO;
679 
680 	return (*tp->t_linesw->l_poll)(tp, events, l);
681 }
682 
683 struct tty *
684 sacomtty(dev_t dev)
685 {
686 	struct sacom_softc *sc =
687 		device_lookup_private(&sacom_cd, COMUNIT(dev));
688 	struct tty *tp = sc->sc_tty;
689 
690 	return tp;
691 }
692 
693 int
694 sacomioctl(dev_t dev, u_long cmd, void *data, int flag, struct lwp *l)
695 {
696 	struct sacom_softc *sc =
697 		device_lookup_private(&sacom_cd, COMUNIT(dev));
698 	struct tty *tp = sc->sc_tty;
699 	int error;
700 	int s;
701 
702 	if (COM_ISALIVE(sc) == 0)
703 		return EIO;
704 
705 	error = (*tp->t_linesw->l_ioctl)(tp, cmd, data, flag, l);
706 	if (error != EPASSTHROUGH)
707 		return error;
708 
709 	error = ttioctl(tp, cmd, data, flag, l);
710 	if (error != EPASSTHROUGH)
711 		return error;
712 
713 	error = 0;
714 
715 	s = splserial();
716 	COM_LOCK(sc);
717 
718 	switch (cmd) {
719 	case TIOCSBRK:
720 		sacom_break(sc, 1);
721 		break;
722 
723 	case TIOCCBRK:
724 		sacom_break(sc, 0);
725 		break;
726 
727 	case TIOCSDTR:
728 		sacom_modem(sc, 1);
729 		break;
730 
731 	case TIOCCDTR:
732 		sacom_modem(sc, 0);
733 		break;
734 
735 	case TIOCGFLAGS:
736 		*(int *)data = sc->sc_swflags;
737 		break;
738 
739 	case TIOCSFLAGS:
740 		error = kauth_authorize_device_tty(l->l_cred,
741 		    KAUTH_DEVICE_TTY_PRIVSET, tp);
742 		if (error)
743 			break;
744 		sc->sc_swflags = *(int *)data;
745 		break;
746 
747 	case TIOCMSET:
748 	case TIOCMBIS:
749 	case TIOCMBIC:
750 		tiocm_to_sacom(sc, cmd, *(int *)data);
751 		break;
752 
753 	case TIOCMGET:
754 		*(int *)data = sacom_to_tiocm(sc);
755 		break;
756 
757 	default:
758 		error = EPASSTHROUGH;
759 		break;
760 	}
761 
762 	COM_UNLOCK(sc);
763 	splx(s);
764 
765 #ifdef COM_DEBUG
766 	if (sacom_debug)
767 		comstatus(sc, "comioctl ");
768 #endif
769 
770 	return error;
771 }
772 
773 static inline void
774 sacom_schedrx(struct sacom_softc *sc)
775 {
776 
777 	sc->sc_rx_ready = 1;
778 
779 	/* Wake up the poller. */
780 	softint_schedule(sc->sc_si);
781 }
782 
783 void
784 sacom_break(struct sacom_softc *sc, int onoff)
785 {
786 
787 	if (onoff)
788 		SET(sc->sc_cr3, CR3_BRK);
789 	else
790 		CLR(sc->sc_cr3, CR3_BRK);
791 
792 	if (!sc->sc_heldchange) {
793 		if (sc->sc_tx_busy) {
794 			sc->sc_heldtbc = sc->sc_tbc;
795 			sc->sc_tbc = 0;
796 			sc->sc_heldchange = 1;
797 		} else
798 			sacom_loadchannelregs(sc);
799 	}
800 }
801 
802 void
803 sacom_modem(struct sacom_softc *sc, int onoff)
804 {
805 	if (!sc->sc_heldchange) {
806 		if (sc->sc_tx_busy) {
807 			sc->sc_heldtbc = sc->sc_tbc;
808 			sc->sc_tbc = 0;
809 			sc->sc_heldchange = 1;
810 		} else
811 			sacom_loadchannelregs(sc);
812 	}
813 }
814 
815 void
816 tiocm_to_sacom(struct sacom_softc *sc, u_long how, int ttybits)
817 {
818 }
819 
820 int
821 sacom_to_tiocm(struct sacom_softc *sc)
822 {
823 	int ttybits = 0;
824 
825 	if (sc->sc_cr3 != 0)
826 		SET(ttybits, TIOCM_LE);
827 
828 	return ttybits;
829 }
830 
831 static u_int
832 cflag2cr0(tcflag_t cflag)
833 {
834 	u_int cr0;
835 
836 	cr0  = (cflag & PARENB) ? CR0_PE : 0;
837 	cr0 |= (cflag & PARODD) ? 0 : CR0_OES;
838 	cr0 |= (cflag & CSTOPB) ? CR0_SBS : 0;
839 	cr0 |= ((cflag & CSIZE) == CS8) ? CR0_DSS : 0;
840 
841 	return cr0;
842 }
843 
844 int
845 sacomparam(struct tty *tp, struct termios *t)
846 {
847 	struct sacom_softc *sc =
848 		device_lookup_private(&sacom_cd, COMUNIT(tp->t_dev));
849 	int ospeed = SACOMSPEED(t->c_ospeed);
850 	u_int cr0;
851 	int s;
852 
853 	if (COM_ISALIVE(sc) == 0)
854 		return EIO;
855 
856 	/* Check requested parameters. */
857 	if (ospeed < 0)
858 		return EINVAL;
859 	if (t->c_ispeed && t->c_ispeed != t->c_ospeed)
860 		return EINVAL;
861 
862 	/*
863 	 * For the console, always force CLOCAL and !HUPCL, so that the port
864 	 * is always active.
865 	 */
866 	if (ISSET(sc->sc_swflags, TIOCFLAG_SOFTCAR) ||
867 	    ISSET(sc->sc_hwflags, COM_HW_CONSOLE)) {
868 		SET(t->c_cflag, CLOCAL);
869 		CLR(t->c_cflag, HUPCL);
870 	}
871 
872 	/*
873 	 * If there were no changes, don't do anything.  This avoids dropping
874 	 * input and improves performance when all we did was frob things like
875 	 * VMIN and VTIME.
876 	 */
877 	if (tp->t_ospeed == t->c_ospeed &&
878 	    tp->t_cflag == t->c_cflag)
879 		return 0;
880 
881 	cr0 = cflag2cr0(t->c_cflag);
882 
883 	s = splserial();
884 	COM_LOCK(sc);
885 
886 	sc->sc_cr0 = cr0;
887 
888 	sc->sc_speed = ospeed;
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 			sacom_loadchannelregs(sc);
902 	}
903 
904 	if (!ISSET(t->c_cflag, CHWFLOW)) {
905 		/* Disable the high water mark. */
906 		if (ISSET(sc->sc_rx_flags, RX_TTY_OVERFLOWED)) {
907 			CLR(sc->sc_rx_flags, RX_TTY_OVERFLOWED);
908 			sacom_schedrx(sc);
909 		}
910 		if (ISSET(sc->sc_rx_flags, RX_TTY_BLOCKED|RX_IBUF_BLOCKED)) {
911 			CLR(sc->sc_rx_flags, RX_TTY_BLOCKED|RX_IBUF_BLOCKED);
912 			sacom_hwiflow(sc);
913 		}
914 	}
915 
916 	COM_UNLOCK(sc);
917 	splx(s);
918 
919 	(void) (*tp->t_linesw->l_modem)(tp, 1);
920 
921 #ifdef COM_DEBUG
922 	if (sacom_debug)
923 		comstatus(sc, "comparam ");
924 #endif
925 
926 	return 0;
927 }
928 
929 void
930 sacom_iflush(struct sacom_softc *sc)
931 {
932 	bus_space_tag_t iot = sc->sc_iot;
933 	bus_space_handle_t ioh = sc->sc_ioh;
934 #ifdef DIAGNOSTIC
935 	int reg;
936 #endif
937 	int timo;
938 
939 #ifdef DIAGNOSTIC
940 	reg = 0xffff;
941 #endif
942 	timo = 50;
943 	/* flush any pending I/O */
944 	if (sc->sc_cr3 & CR3_RXE) {
945 	while (ISSET(bus_space_read_4(iot, ioh, SACOM_SR1), SR1_RNE)
946 	    && --timo)
947 #ifdef DIAGNOSTIC
948 		reg =
949 #else
950 		    (void)
951 #endif
952 		    bus_space_read_4(iot, ioh, SACOM_DR);
953 	}
954 #if 0
955 	/* XXX is it good idea to wait TX finish? */
956 	if (sc->sc_cr3 & CR3_TXE) {
957 	timo = 500;
958 	while (ISSET(bus_space_read_4(iot, ioh, SACOM_SR1), SR1_TBY)
959 	    && --timo)
960 		delay(100);
961 	}
962 #endif
963 #ifdef DIAGNOSTIC
964 	if (!timo)
965 		aprint_debug_dev(sc->sc_dev, "sacom_iflush timeout %02x\n", reg);
966 #endif
967 }
968 
969 void
970 sacom_loadchannelregs(struct sacom_softc *sc)
971 {
972 	bus_space_tag_t iot = sc->sc_iot;
973 	bus_space_handle_t ioh = sc->sc_ioh;
974 
975 	/* XXXXX necessary? */
976 	sacom_iflush(sc);
977 
978 	/* Need to stop engines first. */
979 	bus_space_write_4(iot, ioh, SACOM_CR3, 0);
980 
981 	bus_space_write_4(iot, ioh, SACOM_CR1, sc->sc_speed >> 8);
982 	bus_space_write_4(iot, ioh, SACOM_CR2, sc->sc_speed & 0xff);
983 
984 	bus_space_write_4(iot, ioh, SACOM_CR0, sc->sc_cr0);
985 	bus_space_write_4(iot, ioh, SACOM_CR3, sc->sc_cr3);
986 }
987 
988 int
989 sacomhwiflow(struct tty *tp, int block)
990 {
991 #if 0
992 	struct sacom_softc *sc =
993 		device_lookup_private(&sacom_cd, COMUNIT(tp->t_dev));
994 	int s;
995 
996 	if (COM_ISALIVE(sc) == 0)
997 		return 0;
998 
999 	if (sc->sc_mcr_rts == 0)
1000 		return 0;
1001 
1002 	s = splserial();
1003 	COM_LOCK(sc);
1004 
1005 	if (block) {
1006 		if (!ISSET(sc->sc_rx_flags, RX_TTY_BLOCKED)) {
1007 			SET(sc->sc_rx_flags, RX_TTY_BLOCKED);
1008 			sacom_hwiflow(sc);
1009 		}
1010 	} else {
1011 		if (ISSET(sc->sc_rx_flags, RX_TTY_OVERFLOWED)) {
1012 			CLR(sc->sc_rx_flags, RX_TTY_OVERFLOWED);
1013 			sacom_schedrx(sc);
1014 		}
1015 		if (ISSET(sc->sc_rx_flags, RX_TTY_BLOCKED)) {
1016 			CLR(sc->sc_rx_flags, RX_TTY_BLOCKED);
1017 			sacom_hwiflow(sc);
1018 		}
1019 	}
1020 
1021 	COM_UNLOCK(sc);
1022 	splx(s);
1023 #endif
1024 	return 1;
1025 }
1026 
1027 /*
1028  * (un)block input via hw flowcontrol
1029  */
1030 void
1031 sacom_hwiflow(struct sacom_softc *sc)
1032 {
1033 #if 0
1034 	bus_space_tag_t iot = sc->sc_iot;
1035 	bus_space_handle_t ioh = sc->sc_ioh;
1036 
1037 	/* XXX implement */
1038 #endif
1039 }
1040 
1041 
1042 void
1043 sacomstart(struct tty *tp)
1044 {
1045 	struct sacom_softc *sc =
1046 		device_lookup_private(&sacom_cd, COMUNIT(tp->t_dev));
1047 	bus_space_tag_t iot = sc->sc_iot;
1048 	bus_space_handle_t ioh = sc->sc_ioh;
1049 	int s;
1050 
1051 	if (COM_ISALIVE(sc) == 0)
1052 		return;
1053 
1054 	s = spltty();
1055 	if (ISSET(tp->t_state, TS_BUSY | TS_TIMEOUT | TS_TTSTOP))
1056 		goto out;
1057 	if (!ttypull(tp))
1058 		goto out;
1059 
1060 	/* Grab the first contiguous region of buffer space. */
1061 	{
1062 		u_char *tba;
1063 		int tbc;
1064 
1065 		tba = tp->t_outq.c_cf;
1066 		tbc = ndqb(&tp->t_outq, 0);
1067 
1068 		(void)splserial();
1069 		COM_LOCK(sc);
1070 
1071 		sc->sc_tba = tba;
1072 		sc->sc_tbc = tbc;
1073 	}
1074 
1075 	SET(tp->t_state, TS_BUSY);
1076 	sc->sc_tx_busy = 1;
1077 
1078 	/* Enable transmit completion interrupts if necessary. */
1079 	if (!ISSET(sc->sc_cr3, CR3_TIE)) {
1080 		SET(sc->sc_cr3, CR3_TIE);
1081 		bus_space_write_4(iot, ioh, SACOM_CR3, sc->sc_cr3);
1082 	}
1083 
1084 	/* Output the first chunk of the contiguous buffer. */
1085 	sacom_filltx(sc);
1086 
1087 	COM_UNLOCK(sc);
1088 out:
1089 	splx(s);
1090 	return;
1091 }
1092 
1093 void
1094 sacom_filltx(struct sacom_softc *sc)
1095 {
1096 	bus_space_tag_t iot = sc->sc_iot;
1097 	bus_space_handle_t ioh = sc->sc_ioh;
1098 	int c, n;
1099 
1100 	n = 0;
1101 	while (bus_space_read_4(iot, ioh, SACOM_SR1) & SR1_TNF) {
1102 		if (n == SACOM_TXFIFOLEN || n == sc->sc_tbc)
1103 			break;
1104 		c = *(sc->sc_tba + n);
1105 		c &= 0xff;
1106 		bus_space_write_4(iot, ioh, SACOM_DR, c);
1107 		n++;
1108 	}
1109 	sc->sc_tbc -= n;
1110 	sc->sc_tba += n;
1111 }
1112 
1113 /*
1114  * Stop output on a line.
1115  */
1116 void
1117 sacomstop(struct tty *tp, int flag)
1118 {
1119 	struct sacom_softc *sc =
1120 		device_lookup_private(&sacom_cd, COMUNIT(tp->t_dev));
1121 	int s;
1122 
1123 	s = splserial();
1124 	COM_LOCK(sc);
1125 	if (ISSET(tp->t_state, TS_BUSY)) {
1126 		/* Stop transmitting at the next chunk. */
1127 		sc->sc_tbc = 0;
1128 		sc->sc_heldtbc = 0;
1129 		if (!ISSET(tp->t_state, TS_TTSTOP))
1130 			SET(tp->t_state, TS_FLUSH);
1131 	}
1132 	COM_UNLOCK(sc);
1133 	splx(s);
1134 }
1135 
1136 static inline void
1137 sacom_rxsoft(struct sacom_softc *sc, struct tty *tp)
1138 {
1139 	int (*rint)(int, struct tty *) = tp->t_linesw->l_rint;
1140 	u_char *get, *end;
1141 	u_int cc, scc;
1142 	u_char sr1;
1143 	int code;
1144 	int s;
1145 
1146 	end = sc->sc_ebuf;
1147 	get = sc->sc_rbget;
1148 	scc = cc = SACOM_RING_SIZE - sc->sc_rbavail;
1149 
1150 	while (cc) {
1151 		code = get[0];
1152 		sr1 = get[1];
1153 		if (ISSET(sr1, SR1_FRE))
1154 			SET(code, TTY_FE);
1155 		if (ISSET(sr1, SR1_PRE))
1156 			SET(code, TTY_PE);
1157 		if ((*rint)(code, tp) == -1) {
1158 			/*
1159 			 * The line discipline's buffer is out of space.
1160 			 */
1161 			if (!ISSET(sc->sc_rx_flags, RX_TTY_BLOCKED)) {
1162 				/*
1163 				 * We're either not using flow control, or the
1164 				 * line discipline didn't tell us to block for
1165 				 * some reason.  Either way, we have no way to
1166 				 * know when there's more space available, so
1167 				 * just drop the rest of the data.
1168 				 */
1169 				get += cc << 1;
1170 				if (get >= end)
1171 					get -= SACOM_RING_SIZE << 1;
1172 				cc = 0;
1173 			} else {
1174 				/*
1175 				 * Don't schedule any more receive processing
1176 				 * until the line discipline tells us there's
1177 				 * space available (through comhwiflow()).
1178 				 * Leave the rest of the data in the input
1179 				 * buffer.
1180 				 */
1181 				SET(sc->sc_rx_flags, RX_TTY_OVERFLOWED);
1182 			}
1183 			break;
1184 		}
1185 		get += 2;
1186 		if (get >= end)
1187 			get = sc->sc_rbuf;
1188 		cc--;
1189 	}
1190 
1191 	if (cc != scc) {
1192 		sc->sc_rbget = get;
1193 		s = splserial();
1194 		COM_LOCK(sc);
1195 
1196 		cc = sc->sc_rbavail += scc - cc;
1197 		/* Buffers should be ok again, release possible block. */
1198 		if (cc >= 1) {
1199 			if (ISSET(sc->sc_rx_flags, RX_IBUF_OVERFLOWED)) {
1200 				CLR(sc->sc_rx_flags, RX_IBUF_OVERFLOWED);
1201 				SET(sc->sc_cr3, CR3_RIE);
1202 				bus_space_write_4(sc->sc_iot, sc->sc_ioh,
1203 						  SACOM_CR3, sc->sc_cr3);
1204 			}
1205 		}
1206 		COM_UNLOCK(sc);
1207 		splx(s);
1208 	}
1209 }
1210 
1211 static inline void
1212 sacom_txsoft(struct sacom_softc *sc, struct tty *tp)
1213 {
1214 
1215 	CLR(tp->t_state, TS_BUSY);
1216 	if (ISSET(tp->t_state, TS_FLUSH))
1217 		CLR(tp->t_state, TS_FLUSH);
1218 	else
1219 		ndflush(&tp->t_outq, (int)(sc->sc_tba - tp->t_outq.c_cf));
1220 	(*tp->t_linesw->l_start)(tp);
1221 }
1222 
1223 static inline void
1224 sacom_stsoft(struct sacom_softc *sc, struct tty *tp)
1225 {
1226 }
1227 
1228 void
1229 sacomsoft(void *arg)
1230 {
1231 	struct sacom_softc *sc = arg;
1232 	struct tty *tp;
1233 
1234 	if (COM_ISALIVE(sc) == 0)
1235 		return;
1236 
1237 	tp = sc->sc_tty;
1238 
1239 	if (sc->sc_rx_ready) {
1240 		sc->sc_rx_ready = 0;
1241 		sacom_rxsoft(sc, tp);
1242 	}
1243 
1244 	if (sc->sc_st_check) {
1245 		sc->sc_st_check = 0;
1246 		sacom_stsoft(sc, tp);
1247 	}
1248 
1249 	if (sc->sc_tx_done) {
1250 		sc->sc_tx_done = 0;
1251 		sacom_txsoft(sc, tp);
1252 	}
1253 }
1254 
1255 int
1256 sacomintr(void *arg)
1257 {
1258 	struct sacom_softc *sc = arg;
1259 	bus_space_tag_t iot = sc->sc_iot;
1260 	bus_space_handle_t ioh = sc->sc_ioh;
1261 	u_char *put, *end;
1262 	u_int cc;
1263 	u_int sr0, sr1;
1264 
1265 	if (COM_ISALIVE(sc) == 0)
1266 		return 0;
1267 
1268 	COM_LOCK(sc);
1269 	sr0 = bus_space_read_4(iot, ioh, SACOM_SR0);
1270 	if (!sr0) {
1271 		COM_UNLOCK(sc);
1272 		return 0;
1273 	}
1274 	if (ISSET(sr0, SR0_EIF))
1275 		/* XXX silently discard error bits */
1276 		bus_space_read_4(iot, ioh, SACOM_DR);
1277 	if (ISSET(sr0, SR0_RBB))
1278 		bus_space_write_4(iot, ioh, SACOM_SR0, SR0_RBB);
1279 	if (ISSET(sr0, SR0_REB)) {
1280 		bus_space_write_4(iot, ioh, SACOM_SR0, SR0_REB);
1281 #if defined(DDB) || defined(KGDB)
1282 #ifndef DDB_BREAK_CHAR
1283 		if (ISSET(sc->sc_hwflags, COM_HW_CONSOLE)) {
1284 			console_debugger();
1285 		}
1286 #endif
1287 #endif /* DDB || KGDB */
1288 	}
1289 
1290 
1291 	end = sc->sc_ebuf;
1292 	put = sc->sc_rbput;
1293 	cc = sc->sc_rbavail;
1294 
1295 	sr1 = bus_space_read_4(iot, ioh, SACOM_SR1);
1296 	if (ISSET(sr0, SR0_RFS | SR0_RID)) {
1297 		if (!ISSET(sc->sc_rx_flags, RX_IBUF_OVERFLOWED)) {
1298 			while (cc > 0) {
1299 				if (!ISSET(sr1, SR1_RNE)) {
1300 					bus_space_write_4(iot, ioh, SACOM_SR0,
1301 							  SR0_RID);
1302 					break;
1303 				}
1304 				put[0] = bus_space_read_4(iot, ioh, SACOM_DR);
1305 				put[1] = sr1;
1306 #if defined(DDB) && defined(DDB_BREAK_CHAR)
1307 				if (put[0] == DDB_BREAK_CHAR &&
1308 				    ISSET(sc->sc_hwflags, COM_HW_CONSOLE)) {
1309 					console_debugger();
1310 
1311 					sr1 = bus_space_read_4(iot, ioh, SACOM_SR1);
1312 					continue;
1313 				}
1314 #endif
1315 				put += 2;
1316 				if (put >= end)
1317 					put = sc->sc_rbuf;
1318 				cc--;
1319 
1320 				sr1 = bus_space_read_4(iot, ioh, SACOM_SR1);
1321 			}
1322 
1323 			/*
1324 			 * Current string of incoming characters ended because
1325 			 * no more data was available or we ran out of space.
1326 			 * Schedule a receive event if any data was received.
1327 			 * If we're out of space, turn off receive interrupts.
1328 			 */
1329 			sc->sc_rbput = put;
1330 			sc->sc_rbavail = cc;
1331 			if (!ISSET(sc->sc_rx_flags, RX_TTY_OVERFLOWED))
1332 				sc->sc_rx_ready = 1;
1333 
1334 			/* XXX do RX hardware flow control */
1335 
1336 			/*
1337 			 * If we're out of space, disable receive interrupts
1338 			 * until the queue has drained a bit.
1339 			 */
1340 			if (!cc) {
1341 				SET(sc->sc_rx_flags, RX_IBUF_OVERFLOWED);
1342 				CLR(sc->sc_cr3, CR3_RIE);
1343 				bus_space_write_4(iot, ioh, SACOM_CR3,
1344 						  sc->sc_cr3);
1345 			}
1346 		} else {
1347 #ifdef DIAGNOSTIC
1348 			panic("sacomintr: we shouldn't reach here");
1349 #endif
1350 			CLR(sc->sc_cr3, CR3_RIE);
1351 			bus_space_write_4(iot, ioh, SACOM_CR3, sc->sc_cr3);
1352 		}
1353 	}
1354 
1355 	/*
1356 	 * Done handling any receive interrupts. See if data can be
1357 	 * transmitted as well. Schedule tx done event if no data left
1358 	 * and tty was marked busy.
1359 	 */
1360 	sr0 = bus_space_read_4(iot, ioh, SACOM_SR0);
1361 	if (ISSET(sr0, SR0_TFS)) {
1362 		/*
1363 		 * If we've delayed a parameter change, do it now, and restart
1364 		 * output.
1365 		 * XXX sacom_loadchannelregs() waits TX completion,
1366 		 * XXX resulting in ~0.1s hang (300bps, 4 bytes) in worst case
1367 		 */
1368 		if (sc->sc_heldchange) {
1369 			sacom_loadchannelregs(sc);
1370 			sc->sc_heldchange = 0;
1371 			sc->sc_tbc = sc->sc_heldtbc;
1372 			sc->sc_heldtbc = 0;
1373 		}
1374 
1375 		/* Output the next chunk of the contiguous buffer, if any. */
1376 		if (sc->sc_tbc > 0) {
1377 			sacom_filltx(sc);
1378 		} else {
1379 			/* Disable transmit completion interrupts if necessary. */
1380 			if (ISSET(sc->sc_cr3, CR3_TIE)) {
1381 				CLR(sc->sc_cr3, CR3_TIE);
1382 				bus_space_write_4(iot, ioh, SACOM_CR3,
1383 						  sc->sc_cr3);
1384 			}
1385 			if (sc->sc_tx_busy) {
1386 				sc->sc_tx_busy = 0;
1387 				sc->sc_tx_done = 1;
1388 			}
1389 		}
1390 	}
1391 	COM_UNLOCK(sc);
1392 
1393 	/* Wake up the poller. */
1394 	softint_schedule(sc->sc_si);
1395 
1396 #if NRND > 0 && defined(RND_COM)
1397 	rnd_add_uint32(&sc->rnd_source, iir | lsr);
1398 #endif
1399 	return 1;
1400 }
1401 
1402 static void
1403 sacom_j720_init(device_t parent, device_t self)
1404 {
1405 	struct sa11x0_softc *sasc;
1406 
1407 	sasc = device_private(parent);
1408 
1409 	/* XXX  this should be done at sc->enable function */
1410 	bus_space_write_4(sasc->sc_iot, sasc->sc_gpioh,
1411 	    SAGPIO_PCR, 0xa0000);
1412 	bus_space_write_4(sasc->sc_iot, sasc->sc_gpioh,
1413 	    SAGPIO_PSR, 0x100);
1414 }
1415 
1416 /* Initialization for serial console */
1417 int
1418 sacominit(bus_space_tag_t iot, bus_addr_t iobase, int baud, tcflag_t cflag,
1419     bus_space_handle_t *iohp)
1420 {
1421 	int brd, cr0;
1422 
1423 	if (bus_space_map(iot, iobase, SACOM_NPORTS, 0, iohp))
1424 		aprint_normal("register map failed\n");
1425 
1426 	/* wait for the Tx queue to drain and disable the UART */
1427 	while (bus_space_read_4(iot, *iohp, SACOM_SR1) & SR1_TBY)
1428 		continue;
1429 	bus_space_write_4(iot, *iohp, SACOM_CR3, 0);
1430 
1431 	cr0  = cflag2cr0(cflag);
1432 	bus_space_write_4(iot, *iohp, SACOM_CR0, cr0);
1433 
1434 	brd = SACOMSPEED(baud);
1435 	sacomconsrate = baud;
1436 	sacomconsaddr = iobase;
1437 	sacomconscflag = cflag;
1438 	/* XXX assumes little endian */
1439 	bus_space_write_4(iot, *iohp, SACOM_CR1, brd >> 8);
1440 	bus_space_write_4(iot, *iohp, SACOM_CR2, brd & 0xff);
1441 
1442 	/* enable the UART */
1443 	bus_space_write_4(iot, *iohp, SACOM_CR3, CR3_RXE | CR3_TXE);
1444 
1445 	return 0;
1446 }
1447 
1448 void
1449 sacomcnprobe(struct consdev *cp)
1450 {
1451 	cp->cn_pri = CN_REMOTE;
1452 }
1453 
1454 void
1455 sacomcninit(struct consdev *cp)
1456 {
1457 	if (cp == NULL) {
1458 		/* XXX cp == NULL means that MMU is disabled. */
1459 		sacomconsioh = SACOM3_BASE;
1460 		sacomconstag = &sa11x0_bs_tag;
1461 		cn_tab = &sacomcons;
1462 		return;
1463 	}
1464 
1465 	if (sacominit(&sa11x0_bs_tag, CONADDR, CONSPEED,
1466 			  CONMODE, &sacomconsioh))
1467 		panic("can't init serial console @%x", CONADDR);
1468 	cn_tab = &sacomcons;
1469 	sacomconstag = &sa11x0_bs_tag;
1470 }
1471 
1472 int
1473 sacomcngetc(dev_t dev)
1474 {
1475 	int c, s;
1476 
1477 	s = spltty();	/* XXX do we need this? */
1478 
1479 	while (!(bus_space_read_4(sacomconstag, sacomconsioh, SACOM_SR1)
1480 		 & SR1_RNE)) {
1481 #if defined(DDB) || defined(KGDB)
1482 #ifndef DDB_BREAK_CHAR
1483 		u_int sr0;
1484 		extern int db_active;
1485 
1486 		sr0 = bus_space_read_4(sacomconstag, sacomconsioh, SACOM_SR0);
1487 		if (ISSET(sr0, SR0_RBB))
1488 			bus_space_write_4(sacomconstag, sacomconsioh,
1489 					  SACOM_SR0, SR0_RBB);
1490 		if (ISSET(sr0, SR0_REB)) {
1491 			bus_space_write_4(sacomconstag, sacomconsioh,
1492 					  SACOM_SR0, SR0_REB);
1493 			if (db_active == 0)
1494 				console_debugger();
1495 		}
1496 #endif
1497 #endif /* DDB || KGDB */
1498 	}
1499 
1500 	c = bus_space_read_4(sacomconstag, sacomconsioh, SACOM_DR);
1501 	c &= 0xff;
1502 	splx(s);
1503 
1504 	return c;
1505 }
1506 
1507 void
1508 sacomcnputc(dev_t dev, int c)
1509 {
1510 	int s;
1511 
1512 	s = spltty();	/* XXX do we need this? */
1513 
1514 	while (!(bus_space_read_4(sacomconstag, sacomconsioh, SACOM_SR1)
1515 	    & SR1_TNF))
1516 		continue;
1517 
1518 	bus_space_write_4(sacomconstag, sacomconsioh, SACOM_DR, c);
1519 	splx(s);
1520 }
1521 
1522 void
1523 sacomcnpollc(dev_t dev, int on)
1524 {
1525 
1526 }
1527 
1528 #if 0
1529 #ifdef DEBUG
1530 int
1531 sacomcncharpoll(void)
1532 {
1533 	int c;
1534 
1535 	if (!(bus_space_read_4(sacomconstag, sacomconsioh, SACOM_SR1)
1536 		 & SR1_RNE))
1537 		return -1;
1538 
1539 	c = bus_space_read_4(sacomconstag, sacomconsioh, SACOM_DR);
1540 	c &= 0xff;
1541 
1542 	return c;
1543 }
1544 #endif
1545 #endif
1546 
1547 /* helper function to identify the com ports used by
1548  console or KGDB (and not yet autoconf attached) */
1549 int
1550 sacom_is_console(bus_space_tag_t iot, bus_addr_t iobase,
1551     bus_space_handle_t *ioh)
1552 {
1553 	bus_space_handle_t help;
1554 
1555 	if (!sacomconsattached &&
1556 	    iot == sacomconstag && iobase == sacomconsaddr)
1557 		help = sacomconsioh;
1558 	else
1559 		return 0;
1560 
1561 	if (ioh)
1562 		*ioh = help;
1563 	return 1;
1564 }
1565