xref: /netbsd-src/sys/arch/mips/sibyte/dev/sbscn.c (revision 75f6d617e282811cb173c2ccfbf5df0dd71f7045)
1 /* $NetBSD: sbscn.c,v 1.41 2015/04/13 21:18:42 riastradh Exp $ */
2 
3 /*
4  * Copyright 2000, 2001
5  * Broadcom Corporation. All rights reserved.
6  *
7  * This software is furnished under license and may be used and copied only
8  * in accordance with the following terms and conditions.  Subject to these
9  * conditions, you may download, copy, install, use, modify and distribute
10  * modified or unmodified copies of this software in source and/or binary
11  * form. No title or ownership is transferred hereby.
12  *
13  * 1) Any source code used, modified or distributed must reproduce and
14  *    retain this copyright notice and list of conditions as they appear in
15  *    the source file.
16  *
17  * 2) No right is granted to use any trade name, trademark, or logo of
18  *    Broadcom Corporation.  The "Broadcom Corporation" name may not be
19  *    used to endorse or promote products derived from this software
20  *    without the prior written permission of Broadcom Corporation.
21  *
22  * 3) THIS SOFTWARE IS PROVIDED "AS-IS" AND ANY EXPRESS OR IMPLIED
23  *    WARRANTIES, INCLUDING BUT NOT LIMITED TO, ANY IMPLIED WARRANTIES OF
24  *    MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, OR
25  *    NON-INFRINGEMENT ARE DISCLAIMED. IN NO EVENT SHALL BROADCOM BE LIABLE
26  *    FOR ANY DAMAGES WHATSOEVER, AND IN PARTICULAR, BROADCOM SHALL NOT BE
27  *    LIABLE FOR DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
28  *    CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
29  *    SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
30  *    BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
31  *    WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE
32  *    OR OTHERWISE), EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
33  */
34 
35 /* from: $NetBSD: com.c,v 1.172 2000/05/03 19:19:04 thorpej Exp */
36 
37 /*-
38  * Copyright (c) 1998, 1999 The NetBSD Foundation, Inc.
39  * All rights reserved.
40  *
41  * This code is derived from software contributed to The NetBSD Foundation
42  * by Charles M. Hannum.
43  *
44  * Redistribution and use in source and binary forms, with or without
45  * modification, are permitted provided that the following conditions
46  * are met:
47  * 1. Redistributions of source code must retain the above copyright
48  *    notice, this list of conditions and the following disclaimer.
49  * 2. Redistributions in binary form must reproduce the above copyright
50  *    notice, this list of conditions and the following disclaimer in the
51  *    documentation and/or other materials provided with the distribution.
52  *
53  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
54  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
55  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
56  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
57  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
58  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
59  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
60  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
61  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
62  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
63  * POSSIBILITY OF SUCH DAMAGE.
64  */
65 
66 /*
67  * Copyright (c) 1991 The Regents of the University of California.
68  * All rights reserved.
69  *
70  * Redistribution and use in source and binary forms, with or without
71  * modification, are permitted provided that the following conditions
72  * are met:
73  * 1. Redistributions of source code must retain the above copyright
74  *    notice, this list of conditions and the following disclaimer.
75  * 2. Redistributions in binary form must reproduce the above copyright
76  *    notice, this list of conditions and the following disclaimer in the
77  *    documentation and/or other materials provided with the distribution.
78  * 3. Neither the name of the University nor the names of its contributors
79  *    may be used to endorse or promote products derived from this software
80  *    without specific prior written permission.
81  *
82  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
83  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
84  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
85  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
86  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
87  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
88  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
89  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
90  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
91  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
92  * SUCH DAMAGE.
93  *
94  *	@(#)com.c	7.5 (Berkeley) 5/16/91
95  */
96 
97 /*
98  * `sbscn' driver, supports SiByte SB-1250 SOC DUART.
99  *
100  * This DUART is quite similar in programming model to the scn2681/68681
101  * DUARTs supported by the NetBSD/amiga `mfc' and NetBSD/pc532 `scn'
102  * driver, but substantial rework would have been necessary to make
103  * those drivers sane w.r.t. bus_space (which would then have been
104  * required on NetBSD/sbmips very early on), and to accommodate the
105  * different register mappings.
106  *
107  * So, another driver.  Eventually there should be One True Driver,
108  * but we're not here to save the world.
109  */
110 
111 #include <sys/cdefs.h>
112 __KERNEL_RCSID(0, "$NetBSD: sbscn.c,v 1.41 2015/04/13 21:18:42 riastradh Exp $");
113 
114 #define	SBSCN_DEBUG
115 
116 #include "opt_ddb.h"
117 #include "ioconf.h"
118 
119 #ifdef RND_SBSCN
120 #include <sys/rndsource.h>
121 #endif
122 
123 #include <sys/param.h>
124 #include <sys/systm.h>
125 #include <sys/ioctl.h>
126 #include <sys/select.h>
127 #include <sys/tty.h>
128 #include <sys/proc.h>
129 #include <sys/conf.h>
130 #include <sys/file.h>
131 #include <sys/uio.h>
132 #include <sys/kernel.h>
133 #include <sys/syslog.h>
134 #include <sys/types.h>
135 #include <sys/device.h>
136 #include <sys/malloc.h>
137 #include <sys/vnode.h>
138 #include <sys/kauth.h>
139 #include <sys/intr.h>
140 
141 #include <mips/sibyte/dev/sbobiovar.h>
142 #if 0
143 #include <mips/sibyte/dev/sbscnreg.h>
144 #endif
145 #include <mips/sibyte/dev/sbscnvar.h>
146 #include <dev/cons.h>
147 #include <mips/locore.h>
148 
149 void	sbscn_attach_channel(struct sbscn_softc *sc, int chan, int intr);
150 #if defined(DDB) || defined(KGDB)
151 static void sbscn_enable_debugport(struct sbscn_channel *ch);
152 #endif
153 void	sbscn_config(struct sbscn_channel *ch);
154 void	sbscn_shutdown(struct sbscn_channel *ch);
155 int	sbscn_speed(long, long *);
156 static int cflag2modes(tcflag_t, u_char *, u_char *);
157 int	sbscn_param(struct tty *, struct termios *);
158 void	sbscn_start(struct tty *);
159 int	sbscn_hwiflow(struct tty *, int);
160 
161 void	sbscn_loadchannelregs(struct sbscn_channel *);
162 void	sbscn_dohwiflow(struct sbscn_channel *);
163 void	sbscn_break(struct sbscn_channel *, int);
164 void	sbscn_modem(struct sbscn_channel *, int);
165 void	tiocm_to_sbscn(struct sbscn_channel *, int, int);
166 int	sbscn_to_tiocm(struct sbscn_channel *);
167 void	sbscn_iflush(struct sbscn_channel *);
168 
169 int	sbscn_init(u_long addr, int chan, int rate, tcflag_t cflag);
170 int	sbscn_common_getc(u_long addr, int chan);
171 void	sbscn_common_putc(u_long addr, int chan, int c);
172 void	sbscn_intr(void *arg, uint32_t status, vaddr_t pc);
173 
174 int	sbscn_cngetc(dev_t dev);
175 void	sbscn_cnputc(dev_t dev, int c);
176 void	sbscn_cnpollc(dev_t dev, int on);
177 
178 dev_type_open(sbscnopen);
179 dev_type_close(sbscnclose);
180 dev_type_read(sbscnread);
181 dev_type_write(sbscnwrite);
182 dev_type_ioctl(sbscnioctl);
183 dev_type_stop(sbscnstop);
184 dev_type_tty(sbscntty);
185 dev_type_poll(sbscnpoll);
186 
187 const struct cdevsw sbscn_cdevsw = {
188 	.d_open = sbscnopen,
189 	.d_close = sbscnclose,
190 	.d_read = sbscnread,
191 	.d_write = sbscnwrite,
192 	.d_ioctl = sbscnioctl,
193 	.d_stop = sbscnstop,
194 	.d_tty = sbscntty,
195 	.d_poll = sbscnpoll,
196 	.d_mmap = nommap,
197 	.d_kqfilter = ttykqfilter,
198 	.d_discard = nodiscard,
199 	.d_flag = D_TTY
200 };
201 
202 #define	integrate	static inline
203 void 	sbscn_soft(void *);
204 integrate void sbscn_rxsoft(struct sbscn_channel *, struct tty *);
205 integrate void sbscn_txsoft(struct sbscn_channel *, struct tty *);
206 integrate void sbscn_stsoft(struct sbscn_channel *, struct tty *);
207 integrate void sbscn_schedrx(struct sbscn_channel *);
208 void	sbscn_diag(void *);
209 
210 /*
211  * Make this an option variable one can patch.
212  * But be warned:  this must be a power of 2!
213  */
214 u_int sbscn_rbuf_size = SBSCN_RING_SIZE;
215 
216 /* Stop input when 3/4 of the ring is full; restart when only 1/4 is full. */
217 u_int sbscn_rbuf_hiwat = (SBSCN_RING_SIZE * 1) / 4;
218 u_int sbscn_rbuf_lowat = (SBSCN_RING_SIZE * 3) / 4;
219 
220 static int	sbscn_cons_present;
221 static int	sbscn_cons_attached;
222 static u_long	sbscn_cons_addr;
223 static int	sbscn_cons_chan;
224 static int	sbscn_cons_rate;
225 static tcflag_t	sbscn_cons_cflag;
226 
227 #ifdef KGDB
228 #include <sys/kgdb.h>
229 
230 static int	sbscn_kgdb_present;
231 static int	sbscn_kgdb_attached;
232 static u_long	sbscn_kgdb_addr;
233 static int	sbscn_kgdb_chan;
234 
235 int	sbscn_kgdb_getc(void *);
236 void	sbscn_kgdb_putc(void *, int);
237 #endif /* KGDB */
238 
239 static int	sbscn_match(device_t, cfdata_t, void *);
240 static void	sbscn_attach(device_t, device_t, void *);
241 
242 CFATTACH_DECL_NEW(sbscn, sizeof(struct sbscn_softc),
243     sbscn_match, sbscn_attach, NULL, NULL);
244 
245 #define	READ_REG(rp)		(mips3_ld((volatile uint64_t *)(rp)))
246 #define	WRITE_REG(rp, val)	(mips3_sd((volatile uint64_t *)(rp), (val)))
247 
248 /*
249  * input and output signals are actually the _inverse_ of the bits in the
250  * input and output port registers!
251  */
252 #define	GET_INPUT_SIGNALS(ch) \
253     ((~READ_REG(MIPS_PHYS_TO_KSEG1((ch)->ch_sc->sc_addr + 0x280))) & (ch)->ch_i_mask)
254 #define	SET_OUTPUT_SIGNALS(ch, val) 					\
255     do {								\
256 	int sigs_to_set, sigs_to_clr;					\
257 									\
258 	sigs_to_set = (ch)->ch_o_mask & val;				\
259 	sigs_to_clr = (ch)->ch_o_mask & ~val;				\
260 									\
261 	/* set signals by clearing op bits, and vice versa */		\
262 	WRITE_REG(MIPS_PHYS_TO_KSEG1((ch)->ch_sc->sc_addr + 0x2c0),	\
263 	    sigs_to_set);						\
264 	WRITE_REG(MIPS_PHYS_TO_KSEG1((ch)->ch_sc->sc_addr + 0x2b0),	\
265 	    sigs_to_clr);						\
266     } while (0)
267 
268 static int
269 sbscn_match(device_t parent, cfdata_t match, void *aux)
270 {
271 	struct sbobio_attach_args *sa = aux;
272 
273 	if (sa->sa_locs.sa_type != SBOBIO_DEVTYPE_DUART)
274 		return (0);
275 
276 	return 1;
277 }
278 
279 static void
280 sbscn_attach(device_t parent, device_t self, void *aux)
281 {
282 	struct sbscn_softc *sc = device_private(self);
283 	struct sbobio_attach_args *sa = aux;
284 	int i;
285 
286 	sc->sc_dev = self;
287 	sc->sc_addr = sa->sa_base + sa->sa_locs.sa_offset;
288 
289 	aprint_normal("\n");
290 	for (i = 0; i < 2; i++)
291 		sbscn_attach_channel(sc, i, sa->sa_locs.sa_intr[i]);
292 
293 	/* init duart_opcr */
294 	WRITE_REG(MIPS_PHYS_TO_KSEG1(sc->sc_addr + 0x270), 0);
295 	/* init duart_aux_ctrl */
296 	WRITE_REG(MIPS_PHYS_TO_KSEG1(sc->sc_addr + 0x210), 0x0f); /* XXX */
297 }
298 
299 void
300 sbscn_attach_channel(struct sbscn_softc *sc, int chan, int intr)
301 {
302 	struct sbscn_channel *ch = &sc->sc_channels[chan];
303 	u_long chan_addr;
304 	struct tty *tp;
305 
306 	ch->ch_sc = sc;
307 	ch->ch_num = chan;
308 
309 	chan_addr = sc->sc_addr + (0x100 * chan);
310 	ch->ch_base = (void *)MIPS_PHYS_TO_KSEG1(chan_addr);
311 	ch->ch_isr_base =
312 	    (void *)MIPS_PHYS_TO_KSEG1(sc->sc_addr + 0x220 + (0x20 * chan));
313 	ch->ch_imr_base =
314 	    (void *)MIPS_PHYS_TO_KSEG1(sc->sc_addr + 0x230 + (0x20 * chan));
315 #ifdef XXXCGDnotyet
316 	ch->ch_inchg_base =
317 	    (void *)MIPS_PHYS_TO_KSEG1(sc->sc_addr + 0x2d0 + (0x10 * chan));
318 #endif
319 
320 	ch->ch_i_dcd = ch->ch_i_dcd_pin = 0 /* XXXCGD */;
321 	ch->ch_i_cts = ch->ch_i_cts_pin = 0 /* XXXCGD */;
322 	ch->ch_i_dsr = ch->ch_i_dsr_pin = 0 /* XXXCGD */;
323 	ch->ch_i_ri = ch->ch_i_ri_pin = 0 /* XXXCGD */;
324 	ch->ch_i_mask =
325 	    ch->ch_i_dcd | ch->ch_i_cts | ch->ch_i_dsr | ch->ch_i_ri;
326 	ch->ch_o_dtr = ch->ch_o_dtr_pin = 0 /* XXXCGD */;
327 	ch->ch_o_rts = ch->ch_o_rts_pin = 0 /* XXXCGD */;
328 	ch->ch_o_mask = ch->ch_o_dtr | ch->ch_o_rts;
329 
330 	ch->ch_intrhand = cpu_intr_establish(intr, IPL_SERIAL, sbscn_intr, ch);
331 	callout_init(&ch->ch_diag_callout, 0);
332 
333 	/* Disable interrupts before configuring the device. */
334 	ch->ch_imr = 0;
335 	WRITE_REG(ch->ch_imr_base, ch->ch_imr);
336 
337 	if (sbscn_cons_present &&
338 	    sbscn_cons_addr == chan_addr && sbscn_cons_chan == chan) {
339 		sbscn_cons_attached = 1;
340 
341 		/* Make sure the console is always "hardwired". */
342 		delay(1000);			/* wait for output to finish */
343 		SET(ch->ch_hwflags, SBSCN_HW_CONSOLE);
344 		SET(ch->ch_swflags, TIOCFLAG_SOFTCAR);
345 	}
346 
347 	tp = tty_alloc();
348 	tp->t_oproc = sbscn_start;
349 	tp->t_param = sbscn_param;
350 	tp->t_hwiflow = sbscn_hwiflow;
351 
352 	ch->ch_tty = tp;
353 	ch->ch_rbuf = malloc(sbscn_rbuf_size << 1, M_DEVBUF, M_NOWAIT);
354 	if (ch->ch_rbuf == NULL) {
355 		aprint_error_dev(sc->sc_dev,
356 		    "channel %d: unable to allocate ring buffer\n",
357 		    chan);
358 		return;
359 	}
360 	ch->ch_ebuf = ch->ch_rbuf + (sbscn_rbuf_size << 1);
361 
362 	tty_attach(tp);
363 
364 	if (ISSET(ch->ch_hwflags, SBSCN_HW_CONSOLE)) {
365 		int maj;
366 
367 		/* locate the major number */
368 		maj = cdevsw_lookup_major(&sbscn_cdevsw);
369 
370 		cn_tab->cn_dev = makedev(maj,
371 		    (device_unit(sc->sc_dev) << 1) + chan);
372 
373 		aprint_normal_dev(sc->sc_dev, "channel %d: %s\n",
374 		    chan, "console");
375 	}
376 
377 #ifdef KGDB
378 	/*
379 	 * Allow kgdb to "take over" this port.  If this is
380 	 * the kgdb device, it has exclusive use.
381 	 */
382 	if (sbscn_kgdb_present &&
383 	    sbscn_kgdb_addr == chan_addr && sbscn_kgdb_chan == chan) {
384 		sbscn_kgdb_attached = 1;
385 
386 		SET(sc->sc_hwflags, SBSCN_HW_KGDB);
387 		aprint_normal_dev(sc->sc_dev, "channel %d: %s\n",
388 		    chan, "kgdb");
389 	}
390 #endif
391 
392 	ch->ch_si = softint_establish(SOFTINT_SERIAL, sbscn_soft, ch);
393 
394 #ifdef RND_SBSCN
395 	rnd_attach_source(&ch->ch_rnd_source, device_xname(sc->sc_dev),
396 			  RND_TYPE_TTY, RND_FLAG_COLLECT_TIME|
397 					RND_FLAG_ESTIMATE_TIME);
398 #endif
399 
400 	sbscn_config(ch);
401 
402 	SET(ch->ch_hwflags, SBSCN_HW_DEV_OK);
403 }
404 
405 int
406 sbscn_speed(long speed, long *brcp)
407 {
408 #define	divrnd(n, q)	(((n)*2/(q)+1)/2)	/* divide and round off */
409 
410 	int x, err;
411 	int frequency = 100000000;
412 
413 	*brcp = divrnd(frequency / 20, speed) - 1;
414 
415 	if (speed <= 0)
416 		return (-1);
417 	x = divrnd(frequency / 20, speed);
418 	if (x <= 0)
419 		return (-1);
420 	err = divrnd(((quad_t)frequency) * 1000 / 20, speed * x) - 1000;
421 	if (err < 0)
422 		err = -err;
423 	if (err > SBSCN_TOLERANCE)
424 		return (-1);
425 	*brcp = x - 1;
426 	return (0);
427 
428 #undef	divrnd
429 }
430 
431 #ifdef SBSCN_DEBUG
432 void	sbscn_status(struct sbscn_channel *, const char *);
433 
434 int	sbscn_debug = 0 /* XXXCGD */;
435 
436 void
437 sbscn_status(struct sbscn_channel *ch, const char *str)
438 {
439 	struct sbscn_softc *sc = ch->ch_sc;
440 	struct tty *tp = ch->ch_tty;
441 
442 	aprint_normal_dev(sc->sc_dev,
443 	    "chan %d: %s %sclocal  %sdcd %sts_carr_on %sdtr %stx_stopped\n",
444 	    ch->ch_num, str,
445 	    ISSET(tp->t_cflag, CLOCAL) ? "+" : "-",
446 	    ISSET(ch->ch_iports, ch->ch_i_dcd) ? "+" : "-",
447 	    ISSET(tp->t_state, TS_CARR_ON) ? "+" : "-",
448 	    ISSET(ch->ch_oports, ch->ch_o_dtr) ? "+" : "-",
449 	    ch->ch_tx_stopped ? "+" : "-");
450 
451 	aprint_normal_dev(sc->sc_dev,
452 	    "chan %d: %s %scrtscts %scts %sts_ttstop  %srts %xrx_flags\n",
453 	    ch->ch_num, str,
454 	    ISSET(tp->t_cflag, CRTSCTS) ? "+" : "-",
455 	    ISSET(ch->ch_iports, ch->ch_i_cts) ? "+" : "-",
456 	    ISSET(tp->t_state, TS_TTSTOP) ? "+" : "-",
457 	    ISSET(ch->ch_oports, ch->ch_o_rts) ? "+" : "-",
458 	    ch->ch_rx_flags);
459 }
460 #endif
461 
462 #if defined(DDB) || defined(KGDB)
463 static void
464 sbscn_enable_debugport(struct sbscn_channel *ch)
465 {
466 	int s;
467 
468 	/* Turn on line break interrupt, set carrier. */
469 	s = splserial();
470 
471 #if 0	/* DO NOT turn on break interrupt at this time. */
472 	ch->ch_imr = 0x04;
473 #else
474 	ch->ch_imr = 0x00;
475 #endif
476 	WRITE_REG(ch->ch_imr_base, ch->ch_imr);
477 	SET(ch->ch_oports, ch->ch_o_dtr | ch->ch_o_rts);
478 	SET_OUTPUT_SIGNALS(ch, ch->ch_oports);
479 
480 	splx(s);
481 }
482 #endif
483 
484 void
485 sbscn_config(struct sbscn_channel *ch)
486 {
487 
488 	/* Disable interrupts before configuring the device. */
489 	ch->ch_imr = 0x00;
490 	WRITE_REG(ch->ch_imr_base, ch->ch_imr);
491 
492 #ifdef DDB
493 	if (ISSET(ch->ch_hwflags, SBSCN_HW_CONSOLE))
494 		sbscn_enable_debugport(ch);
495 #endif
496 
497 #ifdef KGDB
498 	/*
499 	 * Allow kgdb to "take over" this port.  If this is
500 	 * the kgdb device, it has exclusive use.
501 	 */
502 	if (ISSET(ch->ch_hwflags, SBSCN_HW_KGDB))
503 		sbscn_enable_debugport(ch);
504 #endif
505 }
506 
507 void
508 sbscn_shutdown(struct sbscn_channel *ch)
509 {
510 	struct tty *tp = ch->ch_tty;
511 	int s;
512 
513 	s = splserial();
514 
515 	/* If we were asserting flow control, then deassert it. */
516 	SET(ch->ch_rx_flags, RX_IBUF_BLOCKED);
517 	sbscn_dohwiflow(ch);
518 
519 	/* Clear any break condition set with TIOCSBRK. */
520 	sbscn_break(ch, 0);
521 
522 	/*
523 	 * Hang up if necessary.  Wait a bit, so the other side has time to
524 	 * notice even if we immediately open the port again.
525 	 * Avoid tsleeping above splhigh().
526 	 */
527 	if (ISSET(tp->t_cflag, HUPCL)) {
528 		sbscn_modem(ch, 0);
529 		splx(s);
530 		/* XXX tsleep will only timeout */
531 		(void) tsleep(ch, TTIPRI, ttclos, hz);
532 		s = splserial();
533 	}
534 
535 	/* Turn off interrupts. */
536 #ifdef DDB
537 	if (ISSET(ch->ch_hwflags, SBSCN_HW_CONSOLE))
538 #if 0	/* DO NOT turn on break interrupt at this time. */
539 		ch->ch_imr = 0x04; /* interrupt on break */
540 #else
541 		ch->ch_imr = 0x00;
542 #endif
543 	else
544 #endif
545 		ch->ch_imr = 0;
546 	WRITE_REG(ch->ch_imr_base, ch->ch_imr);
547 
548 	splx(s);
549 }
550 
551 int
552 sbscnopen(dev_t dev, int flag, int mode, struct lwp *l)
553 {
554 	int chan = SBSCN_CHAN(dev);
555 	struct sbscn_softc *sc;
556 	struct sbscn_channel *ch;
557 	struct tty *tp;
558 	int s, s2;
559 	int error;
560 
561 	sc = device_lookup_private(&sbscn_cd, SBSCN_UNIT(dev));
562 	if (sc == NULL)
563 		return (ENXIO);
564 	ch = &sc->sc_channels[chan];
565 	if (!ISSET(ch->ch_hwflags, SBSCN_HW_DEV_OK) || ch->ch_rbuf == NULL)
566 		return (ENXIO);
567 
568 #ifdef KGDB
569 	/*
570 	 * If this is the kgdb port, no other use is permitted.
571 	 */
572 	if (ISSET(ch->ch_hwflags, SBSCN_HW_KGDB))
573 		return (EBUSY);
574 #endif
575 
576 	tp = ch->ch_tty;
577 
578 	if (kauth_authorize_device_tty(l->l_cred, KAUTH_DEVICE_TTY_OPEN, tp))
579 		return (EBUSY);
580 
581 	s = spltty();
582 
583 	/*
584 	 * Do the following iff this is a first open.
585 	 */
586 	if (!ISSET(tp->t_state, TS_ISOPEN) && tp->t_wopen == 0) {
587 		struct termios t;
588 
589 		tp->t_dev = dev;
590 
591 		s2 = splserial();
592 
593 		/* Turn on receive, break, and status change interrupts. */
594 #if 0	/* DO NOT turn on break or status change interrupt at this time. */
595 		ch->ch_imr = 0xe;
596 #else
597 		ch->ch_imr = 0x2;
598 #endif
599 		WRITE_REG(ch->ch_imr_base, ch->ch_imr);
600 
601 		/* Fetch the current modem control status, needed later. */
602 		ch->ch_iports = GET_INPUT_SIGNALS(ch);
603 		ch->ch_iports_delta = 0;
604 		splx(s2);
605 
606 		/*
607 		 * Initialize the termios status to the defaults.  Add in the
608 		 * sticky bits from TIOCSFLAGS.
609 		 */
610 		t.c_ispeed = 0;
611 		if (ISSET(ch->ch_hwflags, SBSCN_HW_CONSOLE)) {
612 			t.c_ospeed = sbscn_cons_rate;
613 			t.c_cflag = sbscn_cons_cflag;
614 		} else {
615 			t.c_ospeed = TTYDEF_SPEED;
616 			t.c_cflag = TTYDEF_CFLAG;
617 		}
618 		if (ISSET(ch->ch_swflags, TIOCFLAG_CLOCAL))
619 			SET(t.c_cflag, CLOCAL);
620 		if (ISSET(ch->ch_swflags, TIOCFLAG_CRTSCTS))
621 			SET(t.c_cflag, CRTSCTS);
622 		if (ISSET(ch->ch_swflags, TIOCFLAG_MDMBUF))
623 			SET(t.c_cflag, MDMBUF);
624 		/* Make sure sbscn_param() will do something. */
625 		tp->t_ospeed = 0;
626 		(void) sbscn_param(tp, &t);
627 		tp->t_iflag = TTYDEF_IFLAG;
628 		tp->t_oflag = TTYDEF_OFLAG;
629 		tp->t_lflag = TTYDEF_LFLAG;
630 		ttychars(tp);
631 		ttsetwater(tp);
632 
633 		s2 = splserial();
634 
635 		/*
636 		 * Turn on DTR.  We must always do this, even if carrier is not
637 		 * present, because otherwise we'd have to use TIOCSDTR
638 		 * immediately after setting CLOCAL, which applications do not
639 		 * expect.  We always assert DTR while the device is open
640 		 * unless explicitly requested to deassert it.
641 		 */
642 		sbscn_modem(ch, 1);
643 
644 		/* Clear the input ring, and unblock. */
645 		ch->ch_rbput = ch->ch_rbget = ch->ch_rbuf;
646 		ch->ch_rbavail = sbscn_rbuf_size;
647 		sbscn_iflush(ch);
648 		CLR(ch->ch_rx_flags, RX_ANY_BLOCK);
649 		sbscn_dohwiflow(ch);
650 
651 #ifdef SBSCN_DEBUG
652 		if (sbscn_debug)
653 			sbscn_status(ch, "sbscnopen  ");
654 #endif
655 
656 		splx(s2);
657 	}
658 
659 	splx(s);
660 
661 	error = ttyopen(tp, SBSCN_DIALOUT(dev), ISSET(flag, O_NONBLOCK));
662 	if (error)
663 		goto bad;
664 
665 	error = (*tp->t_linesw->l_open)(dev, tp);
666 	if (error)
667 		goto bad;
668 
669 	return (0);
670 
671 bad:
672 	if (!ISSET(tp->t_state, TS_ISOPEN) && tp->t_wopen == 0) {
673 		/*
674 		 * We failed to open the device, and nobody else had it opened.
675 		 * Clean up the state as appropriate.
676 		 */
677 		sbscn_shutdown(ch);
678 	}
679 
680 	return (error);
681 }
682 
683 int
684 sbscnclose(dev_t dev, int flag, int mode, struct lwp *l)
685 {
686 	struct sbscn_softc *sc = device_lookup_private(&sbscn_cd, SBSCN_UNIT(dev));
687 	struct sbscn_channel *ch = &sc->sc_channels[SBSCN_CHAN(dev)];
688 	struct tty *tp = ch->ch_tty;
689 
690 	/* XXX This is for cons.c. */
691 	if (!ISSET(tp->t_state, TS_ISOPEN))
692 		return (0);
693 
694 	(*tp->t_linesw->l_close)(tp, flag);
695 	ttyclose(tp);
696 
697 	if (!ISSET(tp->t_state, TS_ISOPEN) && tp->t_wopen == 0) {
698 		/*
699 		 * Although we got a last close, the device may still be in
700 		 * use; e.g. if this was the dialout node, and there are still
701 		 * processes waiting for carrier on the non-dialout node.
702 		 */
703 		sbscn_shutdown(ch);
704 	}
705 
706 	return (0);
707 }
708 
709 int
710 sbscnread(dev_t dev, struct uio *uio, int flag)
711 {
712 	struct sbscn_softc *sc = device_lookup_private(&sbscn_cd, SBSCN_UNIT(dev));
713 	struct sbscn_channel *ch = &sc->sc_channels[SBSCN_CHAN(dev)];
714 	struct tty *tp = ch->ch_tty;
715 
716 	return ((*tp->t_linesw->l_read)(tp, uio, flag));
717 }
718 
719 int
720 sbscnwrite(dev_t dev, struct uio *uio, int flag)
721 {
722 	struct sbscn_softc *sc = device_lookup_private(&sbscn_cd, SBSCN_UNIT(dev));
723 	struct sbscn_channel *ch = &sc->sc_channels[SBSCN_CHAN(dev)];
724 	struct tty *tp = ch->ch_tty;
725 
726 	return ((*tp->t_linesw->l_write)(tp, uio, flag));
727 }
728 
729 int
730 sbscnpoll(dev_t dev, int events, struct lwp *l)
731 {
732 	struct sbscn_softc *sc = device_lookup_private(&sbscn_cd, SBSCN_UNIT(dev));
733 	struct sbscn_channel *ch = &sc->sc_channels[SBSCN_CHAN(dev)];
734 	struct tty *tp = ch->ch_tty;
735 
736 	return ((*tp->t_linesw->l_poll)(tp, events, l));
737 }
738 
739 struct tty *
740 sbscntty(dev_t dev)
741 {
742 	struct sbscn_softc *sc = device_lookup_private(&sbscn_cd, SBSCN_UNIT(dev));
743 	struct sbscn_channel *ch = &sc->sc_channels[SBSCN_CHAN(dev)];
744 	struct tty *tp = ch->ch_tty;
745 
746 	return (tp);
747 }
748 
749 int
750 sbscnioctl(dev_t dev, u_long cmd, void *data, int flag, struct lwp *l)
751 {
752 	struct sbscn_softc *sc = device_lookup_private(&sbscn_cd, SBSCN_UNIT(dev));
753 	struct sbscn_channel *ch = &sc->sc_channels[SBSCN_CHAN(dev)];
754 	struct tty *tp = ch->ch_tty;
755 	int error;
756 	int s;
757 
758 	error = (*tp->t_linesw->l_ioctl)(tp, cmd, data, flag, l);
759 	if (error != EPASSTHROUGH)
760 		return (error);
761 
762 	error = ttioctl(tp, cmd, data, flag, l);
763 	if (error != EPASSTHROUGH)
764 		return (error);
765 
766 	error = 0;
767 
768 	s = splserial();
769 
770 	switch (cmd) {
771 	case TIOCSBRK:
772 		sbscn_break(ch, 1);
773 		break;
774 
775 	case TIOCCBRK:
776 		sbscn_break(ch, 0);
777 		break;
778 
779 	case TIOCSDTR:
780 		sbscn_modem(ch, 1);
781 		break;
782 
783 	case TIOCCDTR:
784 		sbscn_modem(ch, 0);
785 		break;
786 
787 	case TIOCGFLAGS:
788 		*(int *)data = ch->ch_swflags;
789 		break;
790 
791 	case TIOCSFLAGS:
792 		error = kauth_authorize_device_tty(l->l_cred,
793 		    KAUTH_DEVICE_TTY_PRIVSET, tp);
794 		if (error)
795 			break;
796 		ch->ch_swflags = *(int *)data;
797 		break;
798 
799 	case TIOCMSET:
800 	case TIOCMBIS:
801 	case TIOCMBIC:
802 		tiocm_to_sbscn(ch, cmd, *(int *)data);
803 		break;
804 
805 	case TIOCMGET:
806 		*(int *)data = sbscn_to_tiocm(ch);
807 		break;
808 
809 	default:
810 		error = EPASSTHROUGH;
811 		break;
812 	}
813 
814 	splx(s);
815 
816 #ifdef SBSCN_DEBUG
817 	if (sbscn_debug)
818 		sbscn_status(ch, "sbscn_ioctl ");
819 #endif
820 
821 	return (error);
822 }
823 
824 integrate void
825 sbscn_schedrx(struct sbscn_channel *ch)
826 {
827 
828 	ch->ch_rx_ready = 1;
829 
830 	/* Wake up the poller. */
831 	softint_schedule(ch->ch_si);
832 }
833 
834 void
835 sbscn_break(struct sbscn_channel *ch, int onoff)
836 {
837 
838 /* XXXCGD delay break until not busy */
839 	if (onoff)
840 		WRITE_REG(ch->ch_base + 0x50, 0x60);
841 	else
842 		WRITE_REG(ch->ch_base + 0x50, 0x70);
843 
844 #if 0
845 	if (!ch->ch_heldchange) {
846 		if (ch->ch_tx_busy) {
847 			ch->ch_heldtbc = ch->ch_tbc;
848 			ch->ch_tbc = 0;
849 			ch->ch_heldchange = 1;
850 		} else
851 			sbscn_loadchannelregs(ch);
852 	}
853 #endif
854 }
855 
856 void
857 sbscn_modem(struct sbscn_channel *ch, int onoff)
858 {
859 
860 	if (ch->ch_o_dtr == 0)
861 		return;
862 
863 	if (onoff)
864 		SET(ch->ch_oports, ch->ch_o_dtr);
865 	else
866 		CLR(ch->ch_oports, ch->ch_o_dtr);
867 
868 	if (!ch->ch_heldchange) {
869 		if (ch->ch_tx_busy) {
870 			ch->ch_heldtbc = ch->ch_tbc;
871 			ch->ch_tbc = 0;
872 			ch->ch_heldchange = 1;
873 		} else
874 			sbscn_loadchannelregs(ch);
875 	}
876 }
877 
878 void
879 tiocm_to_sbscn(struct sbscn_channel *ch, int how, int ttybits)
880 {
881 	u_char bits;
882 
883 	bits = 0;
884 	if (ISSET(ttybits, TIOCM_DTR))
885 		SET(bits, ch->ch_o_dtr);
886 	if (ISSET(ttybits, TIOCM_RTS))
887 		SET(bits, ch->ch_o_rts);
888 
889 	switch (how) {
890 	case TIOCMBIC:
891 		CLR(ch->ch_oports, bits);
892 		break;
893 
894 	case TIOCMBIS:
895 		SET(ch->ch_oports, bits);
896 		break;
897 
898 	case TIOCMSET:
899 		ch->ch_oports = bits;
900 		break;
901 	}
902 
903 	if (!ch->ch_heldchange) {
904 		if (ch->ch_tx_busy) {
905 			ch->ch_heldtbc = ch->ch_tbc;
906 			ch->ch_tbc = 0;
907 			ch->ch_heldchange = 1;
908 		} else
909 			sbscn_loadchannelregs(ch);
910 	}
911 }
912 
913 int
914 sbscn_to_tiocm(struct sbscn_channel *ch)
915 {
916 	u_char hwbits;
917 	int ttybits = 0;
918 
919 	hwbits = ch->ch_oports;
920 	if (ISSET(hwbits, ch->ch_o_dtr))
921 		SET(ttybits, TIOCM_DTR);
922 	if (ISSET(hwbits, ch->ch_o_rts))
923 		SET(ttybits, TIOCM_RTS);
924 
925 	hwbits = ch->ch_iports;
926 	if (ISSET(hwbits, ch->ch_i_dcd))
927 		SET(ttybits, TIOCM_CD);
928 	if (ISSET(hwbits, ch->ch_i_cts))
929 		SET(ttybits, TIOCM_CTS);
930 	if (ISSET(hwbits, ch->ch_i_dsr))
931 		SET(ttybits, TIOCM_DSR);
932 	if (ISSET(hwbits, ch->ch_i_ri))
933 		SET(ttybits, TIOCM_RI);
934 
935 	if (ch->ch_imr != 0)
936 		SET(ttybits, TIOCM_LE);
937 
938 	return (ttybits);
939 }
940 
941 static int
942 cflag2modes(tcflag_t cflag, u_char *mode1p, u_char *mode2p)
943 {
944 	u_char mode1;
945 	u_char mode2;
946 	int err = 0;
947 
948 	mode1 = mode2 = 0;
949 
950 	switch (ISSET(cflag, CSIZE)) {
951 	case CS7:
952 		mode1 |= 2;			/* XXX */
953 		break;
954 	default:
955 		err = -1;
956 		/* FALLTHRU for sanity */
957 	case CS8:
958 		mode1 |= 3;			/* XXX */
959 		break;
960 	}
961 	if (!ISSET(cflag, PARENB))
962 		mode1 |= 2 << 3;
963 	else {
964 		mode1 |= 0 << 3;
965 		if (ISSET(cflag, PARODD))
966 			mode1 |= 1 << 2;
967 	}
968 
969 	if (ISSET(cflag, CSTOPB))
970 		mode2 |= 1 << 3;		/* two stop bits XXX not std */
971 
972 	if (ISSET(cflag, CRTSCTS)) {
973 		mode1 |= 1 << 7;
974 		mode2 |= 1 << 4;
975 	}
976 
977 	*mode1p = mode1;
978 	*mode2p = mode2;
979 	return (err);
980 }
981 
982 int
983 sbscn_param(struct tty *tp, struct termios *t)
984 {
985 	struct sbscn_softc *sc = device_lookup_private(&sbscn_cd, SBSCN_UNIT(tp->t_dev));
986 	struct sbscn_channel *ch = &sc->sc_channels[SBSCN_CHAN(tp->t_dev)];
987 	long brc;
988 	u_char mode1, mode2;
989 	int s;
990 
991 /* XXX reset to console parameters if console? */
992 #if 0
993 XXX disable, enable.
994 #endif
995 
996 	/* Check requested parameters. */
997 	if (sbscn_speed(t->c_ospeed, &brc) < 0)
998 		return (EINVAL);
999 	if (t->c_ispeed && t->c_ispeed != t->c_ospeed)
1000 		return (EINVAL);
1001 
1002 	/*
1003 	 * For the console, always force CLOCAL and !HUPCL, so that the port
1004 	 * is always active.
1005 	 */
1006 	if (ISSET(ch->ch_swflags, TIOCFLAG_SOFTCAR) ||
1007 	    ISSET(ch->ch_hwflags, SBSCN_HW_CONSOLE)) {
1008 		SET(t->c_cflag, CLOCAL);
1009 		CLR(t->c_cflag, HUPCL);
1010 	}
1011 
1012 	/*
1013 	 * If there were no changes, don't do anything.  This avoids dropping
1014 	 * input and improves performance when all we did was frob things like
1015 	 * VMIN and VTIME.
1016 	 */
1017 	if (tp->t_ospeed == t->c_ospeed &&
1018 	    tp->t_cflag == t->c_cflag)
1019 		return (0);
1020 
1021 	if (cflag2modes(t->c_cflag, &mode1, &mode2) < 0)
1022 		return (EINVAL);
1023 
1024 	s = splserial();
1025 
1026 	ch->ch_mode1 = mode1;
1027 	ch->ch_mode2 = mode2;
1028 
1029 	/*
1030 	 * If we're not in a mode that assumes a connection is present, then
1031 	 * ignore carrier changes.
1032 	 */
1033 	if (ISSET(t->c_cflag, CLOCAL | MDMBUF))
1034 		ch->ch_i_dcd = 0;
1035 	else
1036 		ch->ch_i_dcd = ch->ch_i_dcd_pin;
1037 	/*
1038 	 * Set the flow control pins depending on the current flow control
1039 	 * mode.
1040 	 */
1041 	if (ISSET(t->c_cflag, CRTSCTS)) {
1042 		ch->ch_o_dtr = ch->ch_o_dtr_pin;
1043 		ch->ch_o_rts = ch->ch_o_rts_pin;
1044 		ch->ch_i_cts = ch->ch_i_cts_pin;
1045 		/* hw controle enable bits in mod regs set by cflag2modes */
1046 	} else if (ISSET(t->c_cflag, MDMBUF)) {
1047 		/*
1048 		 * For DTR/DCD flow control, make sure we don't toggle DTR for
1049 		 * carrier detection.
1050 		 */
1051 		ch->ch_o_dtr = 0;
1052 		ch->ch_o_rts = ch->ch_o_dtr_pin;
1053 		ch->ch_i_cts = ch->ch_i_dcd_pin;
1054 	} else {
1055 		/*
1056 		 * If no flow control, then always set RTS.  This will make
1057 		 * the other side happy if it mistakenly thinks we're doing
1058 		 * RTS/CTS flow control.
1059 		 */
1060 		ch->ch_o_dtr = ch->ch_o_dtr_pin | ch->ch_o_rts_pin;
1061 		ch->ch_o_rts = 0;
1062 		ch->ch_i_cts = 0;
1063 		if (ISSET(ch->ch_oports, ch->ch_o_dtr_pin))
1064 			SET(ch->ch_oports, ch->ch_o_rts_pin);
1065 		else
1066 			CLR(ch->ch_oports, ch->ch_o_rts_pin);
1067 	}
1068 	/* XXX maybe mask the ports which generate intrs? */
1069 
1070 	ch->ch_brc = brc;
1071 
1072 	/* XXX maybe set fifo-full receive mode if RTSCTS and high speed? */
1073 
1074 	/* And copy to tty. */
1075 	tp->t_ispeed = 0;
1076 	tp->t_ospeed = t->c_ospeed;
1077 	tp->t_cflag = t->c_cflag;
1078 
1079 	if (!ch->ch_heldchange) {
1080 		if (ch->ch_tx_busy) {
1081 			ch->ch_heldtbc = ch->ch_tbc;
1082 			ch->ch_tbc = 0;
1083 			ch->ch_heldchange = 1;
1084 		} else
1085 			sbscn_loadchannelregs(ch);
1086 	}
1087 
1088 	if (!ISSET(t->c_cflag, CHWFLOW)) {
1089 		/* Disable the high water mark. */
1090 		ch->ch_r_hiwat = 0;
1091 		ch->ch_r_lowat = 0;
1092 		if (ISSET(ch->ch_rx_flags, RX_TTY_OVERFLOWED)) {
1093 			CLR(ch->ch_rx_flags, RX_TTY_OVERFLOWED);
1094 			sbscn_schedrx(ch);
1095 		}
1096 		if (ISSET(ch->ch_rx_flags, RX_TTY_BLOCKED|RX_IBUF_BLOCKED)) {
1097 			CLR(ch->ch_rx_flags, RX_TTY_BLOCKED|RX_IBUF_BLOCKED);
1098 			sbscn_dohwiflow(ch);
1099 		}
1100 	} else {
1101 		ch->ch_r_hiwat = sbscn_rbuf_hiwat;
1102 		ch->ch_r_lowat = sbscn_rbuf_lowat;
1103 	}
1104 
1105 	splx(s);
1106 
1107 	/*
1108 	 * Update the tty layer's idea of the carrier bit, in case we changed
1109 	 * CLOCAL or MDMBUF.  We don't hang up here; we only do that by
1110 	 * explicit request.
1111 	 */
1112 	(void) (*tp->t_linesw->l_modem)(tp,
1113 	    ISSET(ch->ch_iports, ch->ch_i_dcd));
1114 
1115 #ifdef SBSCN_DEBUG
1116 	if (sbscn_debug)
1117 		sbscn_status(ch, "sbscnparam ");
1118 #endif
1119 
1120 	if (!ISSET(t->c_cflag, CHWFLOW)) {
1121 		if (ch->ch_tx_stopped) {
1122 			ch->ch_tx_stopped = 0;
1123 			sbscn_start(tp);
1124 		}
1125 	}
1126 
1127 	return (0);
1128 }
1129 
1130 void
1131 sbscn_iflush(struct sbscn_channel *ch)
1132 {
1133 #ifdef DIAGNOSTIC
1134 	int reg;
1135 #endif
1136 	int timo;
1137 
1138 #ifdef DIAGNOSTIC
1139 	reg = 0xffff;
1140 #endif
1141 	timo = 50000;
1142 	/* flush any pending I/O */
1143 	while (ISSET(READ_REG(ch->ch_base + 0x20), 0x01)
1144 	    && --timo)
1145 #ifdef DIAGNOSTIC
1146 		reg =
1147 #else
1148 		    (void)
1149 #endif
1150 		    READ_REG(ch->ch_base + 0x60);
1151 #ifdef DIAGNOSTIC
1152 	if (!timo)
1153 		aprint_debug_dev(ch->ch_sc->sc_dev,
1154 		    "sbscn_iflush timeout %02x\n", reg & 0xff);
1155 #endif
1156 }
1157 
1158 void
1159 sbscn_loadchannelregs(struct sbscn_channel *ch)
1160 {
1161 
1162 	/* XXXXX necessary? */
1163 	sbscn_iflush(ch);
1164 
1165 	WRITE_REG(ch->ch_imr_base, 0);
1166 
1167 // XXX disable?
1168 	WRITE_REG(ch->ch_base + 0x00, ch->ch_mode1);
1169 	WRITE_REG(ch->ch_base + 0x10, ch->ch_mode2);
1170 	WRITE_REG(ch->ch_base + 0x30, ch->ch_brc);
1171 
1172 	ch->ch_oports_active = ch->ch_oports;
1173 	SET_OUTPUT_SIGNALS(ch, ch->ch_oports_active);
1174 
1175 	WRITE_REG(ch->ch_imr_base, ch->ch_imr);
1176 }
1177 
1178 int
1179 sbscn_hwiflow(struct tty *tp, int block)
1180 {
1181 	struct sbscn_softc *sc = device_lookup_private(&sbscn_cd, SBSCN_UNIT(tp->t_dev));
1182 	struct sbscn_channel *ch = &sc->sc_channels[SBSCN_CHAN(tp->t_dev)];
1183 	int s;
1184 
1185 	if (ch->ch_o_rts == 0)
1186 		return (0);
1187 
1188 	s = splserial();
1189 	if (block) {
1190 		if (!ISSET(ch->ch_rx_flags, RX_TTY_BLOCKED)) {
1191 			SET(ch->ch_rx_flags, RX_TTY_BLOCKED);
1192 			sbscn_dohwiflow(ch);
1193 		}
1194 	} else {
1195 		if (ISSET(ch->ch_rx_flags, RX_TTY_OVERFLOWED)) {
1196 			CLR(ch->ch_rx_flags, RX_TTY_OVERFLOWED);
1197 			sbscn_schedrx(ch);
1198 		}
1199 		if (ISSET(ch->ch_rx_flags, RX_TTY_BLOCKED)) {
1200 			CLR(ch->ch_rx_flags, RX_TTY_BLOCKED);
1201 			sbscn_dohwiflow(ch);
1202 		}
1203 	}
1204 	splx(s);
1205 	return (1);
1206 }
1207 
1208 /*
1209  * (un)block input via hw flowcontrol
1210  */
1211 void
1212 sbscn_dohwiflow(struct sbscn_channel *ch)
1213 {
1214 
1215 	if (ch->ch_o_rts == 0)
1216 		return;
1217 
1218 	if (ISSET(ch->ch_rx_flags, RX_ANY_BLOCK)) {
1219 		CLR(ch->ch_oports, ch->ch_o_rts);
1220 		CLR(ch->ch_oports_active, ch->ch_o_rts);
1221 	} else {
1222 		SET(ch->ch_oports, ch->ch_o_rts);
1223 		SET(ch->ch_oports_active, ch->ch_o_rts);
1224 	}
1225 	SET_OUTPUT_SIGNALS(ch, ch->ch_oports_active);
1226 }
1227 
1228 void
1229 sbscn_start(struct tty *tp)
1230 {
1231 	struct sbscn_softc *sc = device_lookup_private(&sbscn_cd, SBSCN_UNIT(tp->t_dev));
1232 	struct sbscn_channel *ch = &sc->sc_channels[SBSCN_CHAN(tp->t_dev)];
1233 	int s;
1234 
1235 	s = spltty();
1236 	if (ISSET(tp->t_state, TS_BUSY | TS_TIMEOUT | TS_TTSTOP))
1237 		goto out;
1238 	if (ch->ch_tx_stopped)
1239 		goto out;
1240 	if (!ttypull(tp))
1241 		goto out;
1242 
1243 	/* Grab the first contiguous region of buffer space. */
1244 	{
1245 		u_char *tba;
1246 		int tbc;
1247 
1248 		tba = tp->t_outq.c_cf;
1249 		tbc = ndqb(&tp->t_outq, 0);
1250 
1251 		(void)splserial();
1252 
1253 		ch->ch_tba = tba;
1254 		ch->ch_tbc = tbc;
1255 	}
1256 
1257 	SET(tp->t_state, TS_BUSY);
1258 	ch->ch_tx_busy = 1;
1259 
1260 	/* Enable transmit completion interrupts if necessary. */
1261 	if (!ISSET(ch->ch_imr, 0x1)) {
1262 		SET(ch->ch_imr, 0x1);
1263 		WRITE_REG(ch->ch_imr_base, ch->ch_imr);
1264 	}
1265 
1266 	/* Output the first chunk of the contiguous buffer. */
1267 	{
1268 		u_char c;
1269 
1270 		while (ch->ch_tbc && READ_REG(ch->ch_base + 0x20) & 0x04) {
1271 			c = *ch->ch_tba++;
1272 			ch->ch_tbc--;
1273 			WRITE_REG(ch->ch_base + 0x70, c);
1274 		}
1275 	}
1276 out:
1277 	splx(s);
1278 	return;
1279 }
1280 
1281 /*
1282  * Stop output on a line.
1283  */
1284 void
1285 sbscnstop(struct tty *tp, int flag)
1286 {
1287 	struct sbscn_softc *sc = device_lookup_private(&sbscn_cd, SBSCN_UNIT(tp->t_dev));
1288 	struct sbscn_channel *ch = &sc->sc_channels[SBSCN_CHAN(tp->t_dev)];
1289 	int s;
1290 
1291 	s = splserial();
1292 	if (ISSET(tp->t_state, TS_BUSY)) {
1293 		/* Stop transmitting at the next chunk. */
1294 		ch->ch_tbc = 0;
1295 		ch->ch_heldtbc = 0;
1296 		if (!ISSET(tp->t_state, TS_TTSTOP))
1297 			SET(tp->t_state, TS_FLUSH);
1298 	}
1299 	splx(s);
1300 }
1301 
1302 void
1303 sbscn_diag(void *arg)
1304 {
1305 	struct sbscn_channel *ch = arg;
1306 	struct sbscn_softc *sc = ch->ch_sc;
1307 	int overflows, floods;
1308 	int s;
1309 
1310 	s = splserial();
1311 	overflows = ch->ch_overflows;
1312 	ch->ch_overflows = 0;
1313 	floods = ch->ch_floods;
1314 	ch->ch_floods = 0;
1315 	ch->ch_errors = 0;
1316 	splx(s);
1317 
1318 	log(LOG_WARNING, "%s: channel %d: %d fifo overflow%s, %d ibuf flood%s\n",
1319 	    device_xname(sc->sc_dev), ch->ch_num,
1320 	    overflows, overflows == 1 ? "" : "s",
1321 	    floods, floods == 1 ? "" : "s");
1322 }
1323 
1324 integrate void
1325 sbscn_rxsoft(struct sbscn_channel *ch, struct tty *tp)
1326 {
1327 	int (*rint)(int, struct tty *) = tp->t_linesw->l_rint;
1328 	u_char *get, *end;
1329 	u_int cc, scc;
1330 	u_char sr;
1331 	int code;
1332 	int s;
1333 
1334 	end = ch->ch_ebuf;
1335 	get = ch->ch_rbget;
1336 	scc = cc = sbscn_rbuf_size - ch->ch_rbavail;
1337 
1338 	if (cc == sbscn_rbuf_size) {
1339 		ch->ch_floods++;
1340 		if (ch->ch_errors++ == 0)
1341 			callout_reset(&ch->ch_diag_callout, 60 * hz,
1342 			    sbscn_diag, ch);
1343 	}
1344 
1345 	while (cc) {
1346 		code = get[0];
1347 		sr = get[1];
1348 		if (ISSET(sr, 0xf0)) {
1349 			if (ISSET(sr, 0x10)) {
1350 				ch->ch_overflows++;
1351 				if (ch->ch_errors++ == 0)
1352 					callout_reset(&ch->ch_diag_callout,
1353 					    60 * hz, sbscn_diag, ch);
1354 			}
1355 			if (ISSET(sr, 0xc0))
1356 				SET(code, TTY_FE);
1357 			if (ISSET(sr, 0x20))
1358 				SET(code, TTY_PE);
1359 		}
1360 		if ((*rint)(code, tp) == -1) {
1361 			/*
1362 			 * The line discipline's buffer is out of space.
1363 			 */
1364 			if (!ISSET(ch->ch_rx_flags, RX_TTY_BLOCKED)) {
1365 				/*
1366 				 * We're either not using flow control, or the
1367 				 * line discipline didn't tell us to block for
1368 				 * some reason.  Either way, we have no way to
1369 				 * know when there's more space available, so
1370 				 * just drop the rest of the data.
1371 				 */
1372 				get += cc << 1;
1373 				if (get >= end)
1374 					get -= sbscn_rbuf_size << 1;
1375 				cc = 0;
1376 			} else {
1377 				/*
1378 				 * Don't schedule any more receive processing
1379 				 * until the line discipline tells us there's
1380 				 * space available (through comhwiflow()).
1381 				 * Leave the rest of the data in the input
1382 				 * buffer.
1383 				 */
1384 				SET(ch->ch_rx_flags, RX_TTY_OVERFLOWED);
1385 			}
1386 			break;
1387 		}
1388 		get += 2;
1389 		if (get >= end)
1390 			get = ch->ch_rbuf;
1391 		cc--;
1392 	}
1393 
1394 	if (cc != scc) {
1395 		ch->ch_rbget = get;
1396 		s = splserial();
1397 		cc = ch->ch_rbavail += scc - cc;
1398 		/* Buffers should be ok again, release possible block. */
1399 		if (cc >= ch->ch_r_lowat) {
1400 			if (ISSET(ch->ch_rx_flags, RX_IBUF_OVERFLOWED)) {
1401 				CLR(ch->ch_rx_flags, RX_IBUF_OVERFLOWED);
1402 				SET(ch->ch_imr, 0x02);
1403 				WRITE_REG(ch->ch_imr_base, ch->ch_imr);
1404 			}
1405 			if (ISSET(ch->ch_rx_flags, RX_IBUF_BLOCKED)) {
1406 				CLR(ch->ch_rx_flags, RX_IBUF_BLOCKED);
1407 				sbscn_dohwiflow(ch);
1408 			}
1409 		}
1410 		splx(s);
1411 	}
1412 }
1413 
1414 integrate void
1415 sbscn_txsoft(struct sbscn_channel *ch, struct tty *tp)
1416 {
1417 
1418 	CLR(tp->t_state, TS_BUSY);
1419 	if (ISSET(tp->t_state, TS_FLUSH))
1420 		CLR(tp->t_state, TS_FLUSH);
1421 	else
1422 		ndflush(&tp->t_outq, (int)(ch->ch_tba - tp->t_outq.c_cf));
1423 	(*tp->t_linesw->l_start)(tp);
1424 }
1425 
1426 integrate void
1427 sbscn_stsoft(struct sbscn_channel *ch, struct tty *tp)
1428 {
1429 	u_char iports, delta;
1430 	int s;
1431 
1432 	s = splserial();
1433 	iports = ch->ch_iports;
1434 	delta = ch->ch_iports_delta;
1435 	ch->ch_iports_delta = 0;
1436 	splx(s);
1437 
1438 	if (ISSET(delta, ch->ch_i_dcd)) {
1439 		/*
1440 		 * Inform the tty layer that carrier detect changed.
1441 		 */
1442 		(void) (*tp->t_linesw->l_modem)(tp,
1443 		    ISSET(iports, ch->ch_i_dcd));
1444 	}
1445 
1446 	if (ISSET(delta, ch->ch_i_cts)) {
1447 		/* Block or unblock output according to flow control. */
1448 		if (ISSET(iports, ch->ch_i_cts)) {
1449 			ch->ch_tx_stopped = 0;
1450 			(*tp->t_linesw->l_start)(tp);
1451 		} else {
1452 			ch->ch_tx_stopped = 1;
1453 		}
1454 	}
1455 
1456 #ifdef SBSCN_DEBUG
1457 	if (sbscn_debug)
1458 		sbscn_status(ch, "sbscn_stsoft");
1459 #endif
1460 }
1461 
1462 void
1463 sbscn_soft(void *arg)
1464 {
1465 	struct sbscn_channel *ch = arg;
1466 	struct tty *tp = ch->ch_tty;
1467 
1468 	if (ch->ch_rx_ready) {
1469 		ch->ch_rx_ready = 0;
1470 		sbscn_rxsoft(ch, tp);
1471 	}
1472 
1473 	if (ch->ch_st_check) {
1474 		ch->ch_st_check = 0;
1475 		sbscn_stsoft(ch, tp);
1476 	}
1477 
1478 	if (ch->ch_tx_done) {
1479 		ch->ch_tx_done = 0;
1480 		sbscn_txsoft(ch, tp);
1481 	}
1482 }
1483 
1484 void
1485 sbscn_intr(void *arg, uint32_t status, vaddr_t pc)
1486 {
1487 	struct sbscn_channel *ch = arg;
1488 	u_char *put, *end;
1489 	u_int cc;
1490 	u_char isr, sr;
1491 
1492 	/* read ISR */
1493 	isr = READ_REG(ch->ch_isr_base) & ch->ch_imr;
1494 	if (isr == 0)
1495 		return;
1496 
1497 	end = ch->ch_ebuf;
1498 	put = ch->ch_rbput;
1499 	cc = ch->ch_rbavail;
1500 
1501 	do {
1502 		u_char	iports, delta;
1503 
1504 		if (isr & 0x02) {
1505 
1506 			sr = READ_REG(ch->ch_base + 0x20);
1507 			/* XXX sr 0x01 bit must be set at this point */
1508 
1509 #if defined(DDB) || defined(KGDB)
1510 			if ((sr & 0x80) == 0x80) {
1511 #ifdef DDB
1512 				if (ISSET(ch->ch_hwflags, SBSCN_HW_CONSOLE)) {
1513 					(void)READ_REG(ch->ch_base + 0x60);
1514 					console_debugger();
1515 					continue;
1516 				}
1517 #endif
1518 #ifdef KGDB
1519 				if (ISSET(ch->ch_hwflags, SBSCN_HW_KGDB)) {
1520 					(void)READ_REG(ch->ch_base + 0x60);
1521 					kgdb_connect(1);
1522 					continue;
1523 				}
1524 #endif
1525 			}
1526 #endif /* DDB || KGDB */
1527 
1528 		    	if (!ISSET(ch->ch_rx_flags, RX_IBUF_OVERFLOWED)) {
1529 				while (cc > 0) {
1530 					put[0] = READ_REG(ch->ch_base + 0x60);
1531 					put[1] = sr;
1532 					put += 2;
1533 					if (put >= end)
1534 						put = ch->ch_rbuf;
1535 					cc--;
1536 
1537 					sr = READ_REG(ch->ch_base + 0x20);
1538 					if (!ISSET(sr, 0x02))
1539 						break;
1540 				}
1541 
1542 				/*
1543 				 * Current string of incoming characters ended
1544 				 * because no more data was available or we
1545 				 * ran out of space.  Schedule a receive event
1546 				 * if any data was received.  If we're out of
1547 				 * space, turn off receive interrupts.
1548 				 */
1549 				ch->ch_rbput = put;
1550 				ch->ch_rbavail = cc;
1551 				if (!ISSET(ch->ch_rx_flags, RX_TTY_OVERFLOWED))
1552 					ch->ch_rx_ready = 1;
1553 
1554 				/*
1555 				 * See if we are in danger of overflowing a
1556 				 * buffer. If so, use hardware flow control
1557 				 * to ease the pressure.
1558 				 */
1559 				if (!ISSET(ch->ch_rx_flags, RX_IBUF_BLOCKED) &&
1560 				    cc < ch->ch_r_hiwat) {
1561 					SET(ch->ch_rx_flags, RX_IBUF_BLOCKED);
1562 					sbscn_dohwiflow(ch);
1563 				}
1564 
1565 				/*
1566 				 * If we're out of space, disable receive
1567 				 * interrupts until the queue has drained
1568 				 * a bit.
1569 				 */
1570 				if (!cc) {
1571 					SET(ch->ch_rx_flags,
1572 					    RX_IBUF_OVERFLOWED);
1573 					CLR(ch->ch_imr, 0x02);
1574 					WRITE_REG(ch->ch_imr_base, ch->ch_imr);
1575 				}
1576 			} else {
1577 				/* XXX panic? */
1578 				CLR(ch->ch_imr, 0x02);
1579 				WRITE_REG(ch->ch_imr_base, ch->ch_imr);
1580 				continue;
1581 			}
1582 		}
1583 
1584 		if (isr & 0x01) {
1585 			CLR(ch->ch_imr, 0x01);
1586 			WRITE_REG(ch->ch_imr_base, ch->ch_imr);
1587 		}
1588 
1589 #if 0
1590 XXX
1591 		if (isr & 0x08) {
1592 			clear input signal change!
1593 		}
1594 #endif
1595 		iports = GET_INPUT_SIGNALS(ch);
1596 		delta = iports ^ ch->ch_iports;
1597 		ch->ch_iports = iports;
1598 
1599 		/*
1600 		 * Process normal status changes
1601 		 */
1602 		if (ISSET(delta, ch->ch_i_mask)) {
1603 			SET(ch->ch_iports_delta, delta);
1604 
1605 			/*
1606 			 * Stop output immediately if we lose the output
1607 			 * flow control signal or carrier detect.
1608 			 */
1609 			if (ISSET(~iports, ch->ch_i_mask)) {
1610 				ch->ch_tbc = 0;
1611 				ch->ch_heldtbc = 0;
1612 #ifdef SBSCN_DEBUG
1613 				if (sbscn_debug)
1614 					sbscn_status(ch, "sbscn_intr  ");
1615 #endif
1616 			}
1617 
1618 			ch->ch_st_check = 1;
1619 		}
1620 	} while ((isr = (READ_REG(ch->ch_isr_base) & ch->ch_imr)) != 0);
1621 
1622 	/*
1623 	 * Done handling any receive interrupts and status changes, and
1624 	 * clearing the tx-ready interrupt if it was set.  See if data can
1625 	 * be transmitted as well. Schedule tx done event if no data left
1626 	 * and tty was marked busy.
1627 	 */
1628 	sr = READ_REG(ch->ch_base + 0x20);
1629 	if (ISSET(sr, 0x4)) {
1630 
1631 		/*
1632 		 * If we've delayed a parameter change, do it now, and restart
1633 		 * output.
1634 		 */
1635 		if (ch->ch_heldchange) {
1636 			sbscn_loadchannelregs(ch);
1637 			ch->ch_heldchange = 0;
1638 			ch->ch_tbc = ch->ch_heldtbc;
1639 			ch->ch_heldtbc = 0;
1640 		}
1641 
1642 		/* Output the next chunk of the contiguous buffer, if any. */
1643 		if (ch->ch_tbc > 0) {
1644 			int wrote1;
1645 			u_char c;
1646 
1647 			wrote1 = 0;
1648 			while (ch->ch_tbc &&
1649 			    READ_REG(ch->ch_base + 0x20) & 0x04) {
1650 				wrote1 = 1;
1651 				c = *ch->ch_tba++;
1652 				ch->ch_tbc--;
1653 				WRITE_REG(ch->ch_base + 0x70, c);
1654 			}
1655 			if (wrote1) {
1656 				SET(ch->ch_imr, 0x01);
1657 				WRITE_REG(ch->ch_imr_base, ch->ch_imr);
1658 			}
1659 		} else {
1660 			/*
1661 			 * transmit completion interrupts already disabled,
1662 			 * mark the channel tx state as done.
1663 			 */
1664 			if (ch->ch_tx_busy) {
1665 				ch->ch_tx_busy = 0;
1666 				ch->ch_tx_done = 1;
1667 			}
1668 		}
1669 	}
1670 
1671 	/* Wake up the poller. */
1672 	softint_schedule(ch->ch_si);
1673 
1674 #ifdef RND_SBSCN
1675 	rnd_add_uint32(&ch->ch_rnd_source, isr | sr);
1676 #endif
1677 }
1678 
1679 /*
1680  * The following functions are polled getc and putc routines, shared
1681  * by the console and kgdb glue.
1682  */
1683 
1684 int
1685 sbscn_common_getc(u_long addr, int chan)
1686 {
1687 	int s = splhigh();
1688 	u_long base = MIPS_PHYS_TO_KSEG1(addr + (chan * 0x100));
1689 	int c;
1690 
1691 	/* block until a character becomes available */
1692 	while ((READ_REG(base + 0x20) & 0x01) == 0)
1693 		continue;
1694 
1695 	c = READ_REG(base + 0x60) & 0xff;
1696 	splx(s);
1697 	return (c);
1698 }
1699 
1700 void
1701 sbscn_common_putc(u_long addr, int chan, int c)
1702 {
1703 	int s = splhigh();
1704 	int timo;
1705 	u_long base = MIPS_PHYS_TO_KSEG1(addr + (chan * 0x100));
1706 
1707 	/* wait for any pending transmission to finish */
1708 	timo = 1500000;
1709 	while ((READ_REG(base + 0x20) & 0x08) == 0 && --timo)
1710 		continue;
1711 
1712 	WRITE_REG(base + 0x70, c);
1713 
1714 	/* wait for this transmission to complete */
1715 	timo = 15000000;
1716 	while ((READ_REG(base + 0x20) & 0x08) == 0 && --timo)
1717 		continue;
1718 
1719 	splx(s);
1720 }
1721 
1722 /*
1723  * Initialize UART for use as console or KGDB line.
1724  */
1725 int
1726 sbscn_init(u_long addr, int chan, int rate, tcflag_t cflag)
1727 {
1728 #if 1
1729 	u_long chanregbase = MIPS_PHYS_TO_KSEG1(addr + (chan * 0x100));
1730 	u_long imaskreg = MIPS_PHYS_TO_KSEG1(addr + 0x230 + (chan * 0x20));
1731 	u_char mode1, mode2;
1732 	u_long brc;
1733 	volatile int timo;
1734 
1735 	WRITE_REG(imaskreg, 0);			/* disable channel intrs */
1736 
1737 	/* XXX should we really do the following?  how about only if enabled? */
1738 	/* wait for any pending transmission to finish */
1739 	timo = 1500000;
1740 	while ((READ_REG(chanregbase + 0x20) & 0x08) == 0 && --timo)
1741 		continue;
1742 
1743 	/* XXX: wait a little.  THIS SHOULD NOT BE NECESSARY!!! (?) */
1744 	timo = 1500000;
1745 	while (--timo)
1746 		;
1747 
1748 	WRITE_REG(chanregbase + 0x50, 2 << 4);	/* reset receiver */
1749 	WRITE_REG(chanregbase + 0x50, 3 << 4);	/* reset transmitter */
1750 
1751 	/* set up the line for use */
1752 	(void)cflag2modes(cflag, &mode1, &mode2);
1753 	(void)sbscn_speed(rate, &brc);
1754 	WRITE_REG(chanregbase + 0x00, mode1);
1755 	WRITE_REG(chanregbase + 0x10, mode2);
1756 	WRITE_REG(chanregbase + 0x30, brc);
1757 
1758 	/* enable transmit and receive */
1759 #define	M_DUART_RX_EN			0x01
1760 #define	M_DUART_TX_EN			0x04
1761 	WRITE_REG(chanregbase + 0x50,M_DUART_RX_EN | M_DUART_TX_EN);
1762 #endif
1763 
1764 	/* XXX: wait a little.  THIS SHOULD NOT BE NECESSARY!!! (?) */
1765 	timo = 1500000;
1766 	while (--timo)
1767 		;
1768 
1769 #if 0 /* XXXCGD */
1770 	bus_space_handle_t ioh;
1771 
1772 	if (bus_space_map(iot, iobase, COM_NPORTS, 0, &ioh))
1773 		return (ENOMEM); /* ??? */
1774 
1775 	bus_space_write_1(iot, ioh, com_lcr, LCR_EERS);
1776 	bus_space_write_1(iot, ioh, com_efr, 0);
1777 	bus_space_write_1(iot, ioh, com_lcr, LCR_DLAB);
1778 	rate = comspeed(rate, frequency);
1779 	bus_space_write_1(iot, ioh, com_dlbl, rate);
1780 	bus_space_write_1(iot, ioh, com_dlbh, rate >> 8);
1781 	bus_space_write_1(iot, ioh, com_lcr, cflag2lcr(cflag));
1782 	bus_space_write_1(iot, ioh, com_mcr, MCR_DTR | MCR_RTS);
1783 	bus_space_write_1(iot, ioh, com_fifo,
1784 	    FIFO_ENABLE | FIFO_RCV_RST | FIFO_XMT_RST | FIFO_TRIGGER_1);
1785 	bus_space_write_1(iot, ioh, com_ier, 0);
1786 
1787 	*iohp = ioh;
1788 	return (0);
1789 #endif /* XXXCGD */
1790 	/* XXXCGD */
1791 	return (0);
1792 }
1793 
1794 /*
1795  * Following are all routines needed for sbscn to act as console
1796  */
1797 int
1798 sbscn_cnattach(u_long addr, int chan, int rate, tcflag_t cflag)
1799 {
1800 	int res;
1801 	static struct consdev sbscn_cons = {
1802 		NULL, NULL, sbscn_cngetc, sbscn_cnputc, sbscn_cnpollc, NULL,
1803 		    NULL, NULL, NODEV, CN_NORMAL
1804 	};
1805 
1806 	res = sbscn_init(addr, chan, rate, cflag);
1807 	if (res)
1808 		return (res);
1809 
1810 	cn_tab = &sbscn_cons;
1811 
1812 	sbscn_cons_present = 1;
1813 	sbscn_cons_addr = addr;
1814 	sbscn_cons_chan = chan;
1815 	sbscn_cons_rate = rate;
1816 	sbscn_cons_cflag = cflag;
1817 
1818 	return (0);
1819 }
1820 
1821 int
1822 sbscn_cngetc(dev_t dev)
1823 {
1824 
1825 	return (sbscn_common_getc(sbscn_cons_addr, sbscn_cons_chan));
1826 }
1827 
1828 /*
1829  * Console kernel output character routine.
1830  */
1831 void
1832 sbscn_cnputc(dev_t dev, int c)
1833 {
1834 
1835 	sbscn_common_putc(sbscn_cons_addr, sbscn_cons_chan, c);
1836 }
1837 
1838 void
1839 sbscn_cnpollc(dev_t dev, int on)
1840 {
1841 
1842 }
1843 
1844 #ifdef KGDB
1845 int
1846 sbscn_kgdb_attach(u_long addr, int chan, int rate, tcflag_t cflag)
1847 {
1848 	int res;
1849 
1850 	if (!sbscn_cons_present &&
1851 	    sbscn_cons_addr == addr && sbscn_cons_chan == chan)
1852 		return (EBUSY); /* cannot share with console */
1853 
1854 	res = sbscn_init(addr, chan, rate, cflag);
1855 	if (res)
1856 		return (res);
1857 
1858 	kgdb_attach(sbscn_kgdb_getc, sbscn_kgdb_putc, NULL);
1859 	kgdb_dev = 123; /* unneeded, only to satisfy some tests */
1860 
1861 	sbscn_kgdb_present = 1;
1862 	sbscn_kgdb_addr = addr;
1863 	sbscn_kgdb_chan = chan;
1864 
1865 	return (0);
1866 }
1867 
1868 /* ARGSUSED */
1869 int
1870 sbscn_kgdb_getc(void *arg)
1871 {
1872 
1873 	return (sbscn_common_getc(sbscn_kgdb_addr, sbscn_kgdb_chan));
1874 }
1875 
1876 /* ARGSUSED */
1877 void
1878 sbscn_kgdb_putc(void *arg, int c)
1879 {
1880 
1881 	sbscn_common_getc(sbscn_kgdb_addr, sbscn_kgdb_chan, c);
1882 }
1883 #endif /* KGDB */
1884 
1885 /*
1886  * helper function to identify the sbscn channels used by
1887  * console or KGDB (and not yet autoconf attached)
1888  */
1889 int
1890 sbscn_is_console(u_long addr, int chan)
1891 {
1892 
1893 	if (sbscn_cons_present && !sbscn_cons_attached &&
1894 	    sbscn_cons_addr == addr && sbscn_cons_chan == chan)
1895 		return (1);
1896 #ifdef KGDB
1897 	if (sbscn_kgdb_present && !sbscn_kgdb_attached &&
1898 	    sbscn_kgdb_addr == addr && sbscn_kgdb_chan == chan)
1899 		return (1);
1900 #endif
1901 	return (0);
1902 }
1903