xref: /netbsd-src/sys/arch/mips/sibyte/dev/sbscn.c (revision b7b7574d3bf8eeb51a1fa3977b59142ec6434a55)
1 /* $NetBSD: sbscn.c,v 1.38 2014/03/16 05:20:25 dholland 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 1.38 2014/03/16 05:20:25 dholland Exp $");
113 
114 #define	SBSCN_DEBUG
115 
116 #include "opt_ddb.h"
117 #include "ioconf.h"
118 
119 #include "rnd.h"
120 #ifdef RND_SBSCN
121 #include <sys/rnd.h>
122 #endif
123 
124 #include <sys/param.h>
125 #include <sys/systm.h>
126 #include <sys/ioctl.h>
127 #include <sys/select.h>
128 #include <sys/tty.h>
129 #include <sys/proc.h>
130 #include <sys/conf.h>
131 #include <sys/file.h>
132 #include <sys/uio.h>
133 #include <sys/kernel.h>
134 #include <sys/syslog.h>
135 #include <sys/types.h>
136 #include <sys/device.h>
137 #include <sys/malloc.h>
138 #include <sys/vnode.h>
139 #include <sys/kauth.h>
140 #include <sys/intr.h>
141 
142 #include <mips/sibyte/dev/sbobiovar.h>
143 #if 0
144 #include <mips/sibyte/dev/sbscnreg.h>
145 #endif
146 #include <mips/sibyte/dev/sbscnvar.h>
147 #include <dev/cons.h>
148 #include <mips/locore.h>
149 
150 void	sbscn_attach_channel(struct sbscn_softc *sc, int chan, int intr);
151 #if defined(DDB) || defined(KGDB)
152 static void sbscn_enable_debugport(struct sbscn_channel *ch);
153 #endif
154 void	sbscn_config(struct sbscn_channel *ch);
155 void	sbscn_shutdown(struct sbscn_channel *ch);
156 int	sbscn_speed(long, long *);
157 static int cflag2modes(tcflag_t, u_char *, u_char *);
158 int	sbscn_param(struct tty *, struct termios *);
159 void	sbscn_start(struct tty *);
160 int	sbscn_hwiflow(struct tty *, int);
161 
162 void	sbscn_loadchannelregs(struct sbscn_channel *);
163 void	sbscn_dohwiflow(struct sbscn_channel *);
164 void	sbscn_break(struct sbscn_channel *, int);
165 void	sbscn_modem(struct sbscn_channel *, int);
166 void	tiocm_to_sbscn(struct sbscn_channel *, int, int);
167 int	sbscn_to_tiocm(struct sbscn_channel *);
168 void	sbscn_iflush(struct sbscn_channel *);
169 
170 int	sbscn_init(u_long addr, int chan, int rate, tcflag_t cflag);
171 int	sbscn_common_getc(u_long addr, int chan);
172 void	sbscn_common_putc(u_long addr, int chan, int c);
173 void	sbscn_intr(void *arg, uint32_t status, vaddr_t pc);
174 
175 int	sbscn_cngetc(dev_t dev);
176 void	sbscn_cnputc(dev_t dev, int c);
177 void	sbscn_cnpollc(dev_t dev, int on);
178 
179 dev_type_open(sbscnopen);
180 dev_type_close(sbscnclose);
181 dev_type_read(sbscnread);
182 dev_type_write(sbscnwrite);
183 dev_type_ioctl(sbscnioctl);
184 dev_type_stop(sbscnstop);
185 dev_type_tty(sbscntty);
186 dev_type_poll(sbscnpoll);
187 
188 const struct cdevsw sbscn_cdevsw = {
189 	.d_open = sbscnopen,
190 	.d_close = sbscnclose,
191 	.d_read = sbscnread,
192 	.d_write = sbscnwrite,
193 	.d_ioctl = sbscnioctl,
194 	.d_stop = sbscnstop,
195 	.d_tty = sbscntty,
196 	.d_poll = sbscnpoll,
197 	.d_mmap = nommap,
198 	.d_kqfilter = ttykqfilter,
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, 0);
397 #endif
398 
399 	sbscn_config(ch);
400 
401 	SET(ch->ch_hwflags, SBSCN_HW_DEV_OK);
402 }
403 
404 int
405 sbscn_speed(long speed, long *brcp)
406 {
407 #define	divrnd(n, q)	(((n)*2/(q)+1)/2)	/* divide and round off */
408 
409 	int x, err;
410 	int frequency = 100000000;
411 
412 	*brcp = divrnd(frequency / 20, speed) - 1;
413 
414 	if (speed <= 0)
415 		return (-1);
416 	x = divrnd(frequency / 20, speed);
417 	if (x <= 0)
418 		return (-1);
419 	err = divrnd(((quad_t)frequency) * 1000 / 20, speed * x) - 1000;
420 	if (err < 0)
421 		err = -err;
422 	if (err > SBSCN_TOLERANCE)
423 		return (-1);
424 	*brcp = x - 1;
425 	return (0);
426 
427 #undef	divrnd
428 }
429 
430 #ifdef SBSCN_DEBUG
431 void	sbscn_status(struct sbscn_channel *, const char *);
432 
433 int	sbscn_debug = 0 /* XXXCGD */;
434 
435 void
436 sbscn_status(struct sbscn_channel *ch, const char *str)
437 {
438 	struct sbscn_softc *sc = ch->ch_sc;
439 	struct tty *tp = ch->ch_tty;
440 
441 	aprint_normal_dev(sc->sc_dev,
442 	    "chan %d: %s %sclocal  %sdcd %sts_carr_on %sdtr %stx_stopped\n",
443 	    ch->ch_num, str,
444 	    ISSET(tp->t_cflag, CLOCAL) ? "+" : "-",
445 	    ISSET(ch->ch_iports, ch->ch_i_dcd) ? "+" : "-",
446 	    ISSET(tp->t_state, TS_CARR_ON) ? "+" : "-",
447 	    ISSET(ch->ch_oports, ch->ch_o_dtr) ? "+" : "-",
448 	    ch->ch_tx_stopped ? "+" : "-");
449 
450 	aprint_normal_dev(sc->sc_dev,
451 	    "chan %d: %s %scrtscts %scts %sts_ttstop  %srts %xrx_flags\n",
452 	    ch->ch_num, str,
453 	    ISSET(tp->t_cflag, CRTSCTS) ? "+" : "-",
454 	    ISSET(ch->ch_iports, ch->ch_i_cts) ? "+" : "-",
455 	    ISSET(tp->t_state, TS_TTSTOP) ? "+" : "-",
456 	    ISSET(ch->ch_oports, ch->ch_o_rts) ? "+" : "-",
457 	    ch->ch_rx_flags);
458 }
459 #endif
460 
461 #if defined(DDB) || defined(KGDB)
462 static void
463 sbscn_enable_debugport(struct sbscn_channel *ch)
464 {
465 	int s;
466 
467 	/* Turn on line break interrupt, set carrier. */
468 	s = splserial();
469 
470 #if 0	/* DO NOT turn on break interrupt at this time. */
471 	ch->ch_imr = 0x04;
472 #else
473 	ch->ch_imr = 0x00;
474 #endif
475 	WRITE_REG(ch->ch_imr_base, ch->ch_imr);
476 	SET(ch->ch_oports, ch->ch_o_dtr | ch->ch_o_rts);
477 	SET_OUTPUT_SIGNALS(ch, ch->ch_oports);
478 
479 	splx(s);
480 }
481 #endif
482 
483 void
484 sbscn_config(struct sbscn_channel *ch)
485 {
486 
487 	/* Disable interrupts before configuring the device. */
488 	ch->ch_imr = 0x00;
489 	WRITE_REG(ch->ch_imr_base, ch->ch_imr);
490 
491 #ifdef DDB
492 	if (ISSET(ch->ch_hwflags, SBSCN_HW_CONSOLE))
493 		sbscn_enable_debugport(ch);
494 #endif
495 
496 #ifdef KGDB
497 	/*
498 	 * Allow kgdb to "take over" this port.  If this is
499 	 * the kgdb device, it has exclusive use.
500 	 */
501 	if (ISSET(ch->ch_hwflags, SBSCN_HW_KGDB))
502 		sbscn_enable_debugport(ch);
503 #endif
504 }
505 
506 void
507 sbscn_shutdown(struct sbscn_channel *ch)
508 {
509 	struct tty *tp = ch->ch_tty;
510 	int s;
511 
512 	s = splserial();
513 
514 	/* If we were asserting flow control, then deassert it. */
515 	SET(ch->ch_rx_flags, RX_IBUF_BLOCKED);
516 	sbscn_dohwiflow(ch);
517 
518 	/* Clear any break condition set with TIOCSBRK. */
519 	sbscn_break(ch, 0);
520 
521 	/*
522 	 * Hang up if necessary.  Wait a bit, so the other side has time to
523 	 * notice even if we immediately open the port again.
524 	 * Avoid tsleeping above splhigh().
525 	 */
526 	if (ISSET(tp->t_cflag, HUPCL)) {
527 		sbscn_modem(ch, 0);
528 		splx(s);
529 		/* XXX tsleep will only timeout */
530 		(void) tsleep(ch, TTIPRI, ttclos, hz);
531 		s = splserial();
532 	}
533 
534 	/* Turn off interrupts. */
535 #ifdef DDB
536 	if (ISSET(ch->ch_hwflags, SBSCN_HW_CONSOLE))
537 #if 0	/* DO NOT turn on break interrupt at this time. */
538 		ch->ch_imr = 0x04; /* interrupt on break */
539 #else
540 		ch->ch_imr = 0x00;
541 #endif
542 	else
543 #endif
544 		ch->ch_imr = 0;
545 	WRITE_REG(ch->ch_imr_base, ch->ch_imr);
546 
547 	splx(s);
548 }
549 
550 int
551 sbscnopen(dev_t dev, int flag, int mode, struct lwp *l)
552 {
553 	int chan = SBSCN_CHAN(dev);
554 	struct sbscn_softc *sc;
555 	struct sbscn_channel *ch;
556 	struct tty *tp;
557 	int s, s2;
558 	int error;
559 
560 	sc = device_lookup_private(&sbscn_cd, SBSCN_UNIT(dev));
561 	if (sc == NULL)
562 		return (ENXIO);
563 	ch = &sc->sc_channels[chan];
564 	if (!ISSET(ch->ch_hwflags, SBSCN_HW_DEV_OK) || ch->ch_rbuf == NULL)
565 		return (ENXIO);
566 
567 #ifdef KGDB
568 	/*
569 	 * If this is the kgdb port, no other use is permitted.
570 	 */
571 	if (ISSET(ch->ch_hwflags, SBSCN_HW_KGDB))
572 		return (EBUSY);
573 #endif
574 
575 	tp = ch->ch_tty;
576 
577 	if (kauth_authorize_device_tty(l->l_cred, KAUTH_DEVICE_TTY_OPEN, tp))
578 		return (EBUSY);
579 
580 	s = spltty();
581 
582 	/*
583 	 * Do the following iff this is a first open.
584 	 */
585 	if (!ISSET(tp->t_state, TS_ISOPEN) && tp->t_wopen == 0) {
586 		struct termios t;
587 
588 		tp->t_dev = dev;
589 
590 		s2 = splserial();
591 
592 		/* Turn on receive, break, and status change interrupts. */
593 #if 0	/* DO NOT turn on break or status change interrupt at this time. */
594 		ch->ch_imr = 0xe;
595 #else
596 		ch->ch_imr = 0x2;
597 #endif
598 		WRITE_REG(ch->ch_imr_base, ch->ch_imr);
599 
600 		/* Fetch the current modem control status, needed later. */
601 		ch->ch_iports = GET_INPUT_SIGNALS(ch);
602 		ch->ch_iports_delta = 0;
603 		splx(s2);
604 
605 		/*
606 		 * Initialize the termios status to the defaults.  Add in the
607 		 * sticky bits from TIOCSFLAGS.
608 		 */
609 		t.c_ispeed = 0;
610 		if (ISSET(ch->ch_hwflags, SBSCN_HW_CONSOLE)) {
611 			t.c_ospeed = sbscn_cons_rate;
612 			t.c_cflag = sbscn_cons_cflag;
613 		} else {
614 			t.c_ospeed = TTYDEF_SPEED;
615 			t.c_cflag = TTYDEF_CFLAG;
616 		}
617 		if (ISSET(ch->ch_swflags, TIOCFLAG_CLOCAL))
618 			SET(t.c_cflag, CLOCAL);
619 		if (ISSET(ch->ch_swflags, TIOCFLAG_CRTSCTS))
620 			SET(t.c_cflag, CRTSCTS);
621 		if (ISSET(ch->ch_swflags, TIOCFLAG_MDMBUF))
622 			SET(t.c_cflag, MDMBUF);
623 		/* Make sure sbscn_param() will do something. */
624 		tp->t_ospeed = 0;
625 		(void) sbscn_param(tp, &t);
626 		tp->t_iflag = TTYDEF_IFLAG;
627 		tp->t_oflag = TTYDEF_OFLAG;
628 		tp->t_lflag = TTYDEF_LFLAG;
629 		ttychars(tp);
630 		ttsetwater(tp);
631 
632 		s2 = splserial();
633 
634 		/*
635 		 * Turn on DTR.  We must always do this, even if carrier is not
636 		 * present, because otherwise we'd have to use TIOCSDTR
637 		 * immediately after setting CLOCAL, which applications do not
638 		 * expect.  We always assert DTR while the device is open
639 		 * unless explicitly requested to deassert it.
640 		 */
641 		sbscn_modem(ch, 1);
642 
643 		/* Clear the input ring, and unblock. */
644 		ch->ch_rbput = ch->ch_rbget = ch->ch_rbuf;
645 		ch->ch_rbavail = sbscn_rbuf_size;
646 		sbscn_iflush(ch);
647 		CLR(ch->ch_rx_flags, RX_ANY_BLOCK);
648 		sbscn_dohwiflow(ch);
649 
650 #ifdef SBSCN_DEBUG
651 		if (sbscn_debug)
652 			sbscn_status(ch, "sbscnopen  ");
653 #endif
654 
655 		splx(s2);
656 	}
657 
658 	splx(s);
659 
660 	error = ttyopen(tp, SBSCN_DIALOUT(dev), ISSET(flag, O_NONBLOCK));
661 	if (error)
662 		goto bad;
663 
664 	error = (*tp->t_linesw->l_open)(dev, tp);
665 	if (error)
666 		goto bad;
667 
668 	return (0);
669 
670 bad:
671 	if (!ISSET(tp->t_state, TS_ISOPEN) && tp->t_wopen == 0) {
672 		/*
673 		 * We failed to open the device, and nobody else had it opened.
674 		 * Clean up the state as appropriate.
675 		 */
676 		sbscn_shutdown(ch);
677 	}
678 
679 	return (error);
680 }
681 
682 int
683 sbscnclose(dev_t dev, int flag, int mode, struct lwp *l)
684 {
685 	struct sbscn_softc *sc = device_lookup_private(&sbscn_cd, SBSCN_UNIT(dev));
686 	struct sbscn_channel *ch = &sc->sc_channels[SBSCN_CHAN(dev)];
687 	struct tty *tp = ch->ch_tty;
688 
689 	/* XXX This is for cons.c. */
690 	if (!ISSET(tp->t_state, TS_ISOPEN))
691 		return (0);
692 
693 	(*tp->t_linesw->l_close)(tp, flag);
694 	ttyclose(tp);
695 
696 	if (!ISSET(tp->t_state, TS_ISOPEN) && tp->t_wopen == 0) {
697 		/*
698 		 * Although we got a last close, the device may still be in
699 		 * use; e.g. if this was the dialout node, and there are still
700 		 * processes waiting for carrier on the non-dialout node.
701 		 */
702 		sbscn_shutdown(ch);
703 	}
704 
705 	return (0);
706 }
707 
708 int
709 sbscnread(dev_t dev, struct uio *uio, int flag)
710 {
711 	struct sbscn_softc *sc = device_lookup_private(&sbscn_cd, SBSCN_UNIT(dev));
712 	struct sbscn_channel *ch = &sc->sc_channels[SBSCN_CHAN(dev)];
713 	struct tty *tp = ch->ch_tty;
714 
715 	return ((*tp->t_linesw->l_read)(tp, uio, flag));
716 }
717 
718 int
719 sbscnwrite(dev_t dev, struct uio *uio, int flag)
720 {
721 	struct sbscn_softc *sc = device_lookup_private(&sbscn_cd, SBSCN_UNIT(dev));
722 	struct sbscn_channel *ch = &sc->sc_channels[SBSCN_CHAN(dev)];
723 	struct tty *tp = ch->ch_tty;
724 
725 	return ((*tp->t_linesw->l_write)(tp, uio, flag));
726 }
727 
728 int
729 sbscnpoll(dev_t dev, int events, struct lwp *l)
730 {
731 	struct sbscn_softc *sc = device_lookup_private(&sbscn_cd, SBSCN_UNIT(dev));
732 	struct sbscn_channel *ch = &sc->sc_channels[SBSCN_CHAN(dev)];
733 	struct tty *tp = ch->ch_tty;
734 
735 	return ((*tp->t_linesw->l_poll)(tp, events, l));
736 }
737 
738 struct tty *
739 sbscntty(dev_t dev)
740 {
741 	struct sbscn_softc *sc = device_lookup_private(&sbscn_cd, SBSCN_UNIT(dev));
742 	struct sbscn_channel *ch = &sc->sc_channels[SBSCN_CHAN(dev)];
743 	struct tty *tp = ch->ch_tty;
744 
745 	return (tp);
746 }
747 
748 int
749 sbscnioctl(dev_t dev, u_long cmd, void *data, int flag, struct lwp *l)
750 {
751 	struct sbscn_softc *sc = device_lookup_private(&sbscn_cd, SBSCN_UNIT(dev));
752 	struct sbscn_channel *ch = &sc->sc_channels[SBSCN_CHAN(dev)];
753 	struct tty *tp = ch->ch_tty;
754 	int error;
755 	int s;
756 
757 	error = (*tp->t_linesw->l_ioctl)(tp, cmd, data, flag, l);
758 	if (error != EPASSTHROUGH)
759 		return (error);
760 
761 	error = ttioctl(tp, cmd, data, flag, l);
762 	if (error != EPASSTHROUGH)
763 		return (error);
764 
765 	error = 0;
766 
767 	s = splserial();
768 
769 	switch (cmd) {
770 	case TIOCSBRK:
771 		sbscn_break(ch, 1);
772 		break;
773 
774 	case TIOCCBRK:
775 		sbscn_break(ch, 0);
776 		break;
777 
778 	case TIOCSDTR:
779 		sbscn_modem(ch, 1);
780 		break;
781 
782 	case TIOCCDTR:
783 		sbscn_modem(ch, 0);
784 		break;
785 
786 	case TIOCGFLAGS:
787 		*(int *)data = ch->ch_swflags;
788 		break;
789 
790 	case TIOCSFLAGS:
791 		error = kauth_authorize_device_tty(l->l_cred,
792 		    KAUTH_DEVICE_TTY_PRIVSET, tp);
793 		if (error)
794 			break;
795 		ch->ch_swflags = *(int *)data;
796 		break;
797 
798 	case TIOCMSET:
799 	case TIOCMBIS:
800 	case TIOCMBIC:
801 		tiocm_to_sbscn(ch, cmd, *(int *)data);
802 		break;
803 
804 	case TIOCMGET:
805 		*(int *)data = sbscn_to_tiocm(ch);
806 		break;
807 
808 	default:
809 		error = EPASSTHROUGH;
810 		break;
811 	}
812 
813 	splx(s);
814 
815 #ifdef SBSCN_DEBUG
816 	if (sbscn_debug)
817 		sbscn_status(ch, "sbscn_ioctl ");
818 #endif
819 
820 	return (error);
821 }
822 
823 integrate void
824 sbscn_schedrx(struct sbscn_channel *ch)
825 {
826 
827 	ch->ch_rx_ready = 1;
828 
829 	/* Wake up the poller. */
830 	softint_schedule(ch->ch_si);
831 }
832 
833 void
834 sbscn_break(struct sbscn_channel *ch, int onoff)
835 {
836 
837 /* XXXCGD delay break until not busy */
838 	if (onoff)
839 		WRITE_REG(ch->ch_base + 0x50, 0x60);
840 	else
841 		WRITE_REG(ch->ch_base + 0x50, 0x70);
842 
843 #if 0
844 	if (!ch->ch_heldchange) {
845 		if (ch->ch_tx_busy) {
846 			ch->ch_heldtbc = ch->ch_tbc;
847 			ch->ch_tbc = 0;
848 			ch->ch_heldchange = 1;
849 		} else
850 			sbscn_loadchannelregs(ch);
851 	}
852 #endif
853 }
854 
855 void
856 sbscn_modem(struct sbscn_channel *ch, int onoff)
857 {
858 
859 	if (ch->ch_o_dtr == 0)
860 		return;
861 
862 	if (onoff)
863 		SET(ch->ch_oports, ch->ch_o_dtr);
864 	else
865 		CLR(ch->ch_oports, ch->ch_o_dtr);
866 
867 	if (!ch->ch_heldchange) {
868 		if (ch->ch_tx_busy) {
869 			ch->ch_heldtbc = ch->ch_tbc;
870 			ch->ch_tbc = 0;
871 			ch->ch_heldchange = 1;
872 		} else
873 			sbscn_loadchannelregs(ch);
874 	}
875 }
876 
877 void
878 tiocm_to_sbscn(struct sbscn_channel *ch, int how, int ttybits)
879 {
880 	u_char bits;
881 
882 	bits = 0;
883 	if (ISSET(ttybits, TIOCM_DTR))
884 		SET(bits, ch->ch_o_dtr);
885 	if (ISSET(ttybits, TIOCM_RTS))
886 		SET(bits, ch->ch_o_rts);
887 
888 	switch (how) {
889 	case TIOCMBIC:
890 		CLR(ch->ch_oports, bits);
891 		break;
892 
893 	case TIOCMBIS:
894 		SET(ch->ch_oports, bits);
895 		break;
896 
897 	case TIOCMSET:
898 		ch->ch_oports = bits;
899 		break;
900 	}
901 
902 	if (!ch->ch_heldchange) {
903 		if (ch->ch_tx_busy) {
904 			ch->ch_heldtbc = ch->ch_tbc;
905 			ch->ch_tbc = 0;
906 			ch->ch_heldchange = 1;
907 		} else
908 			sbscn_loadchannelregs(ch);
909 	}
910 }
911 
912 int
913 sbscn_to_tiocm(struct sbscn_channel *ch)
914 {
915 	u_char hwbits;
916 	int ttybits = 0;
917 
918 	hwbits = ch->ch_oports;
919 	if (ISSET(hwbits, ch->ch_o_dtr))
920 		SET(ttybits, TIOCM_DTR);
921 	if (ISSET(hwbits, ch->ch_o_rts))
922 		SET(ttybits, TIOCM_RTS);
923 
924 	hwbits = ch->ch_iports;
925 	if (ISSET(hwbits, ch->ch_i_dcd))
926 		SET(ttybits, TIOCM_CD);
927 	if (ISSET(hwbits, ch->ch_i_cts))
928 		SET(ttybits, TIOCM_CTS);
929 	if (ISSET(hwbits, ch->ch_i_dsr))
930 		SET(ttybits, TIOCM_DSR);
931 	if (ISSET(hwbits, ch->ch_i_ri))
932 		SET(ttybits, TIOCM_RI);
933 
934 	if (ch->ch_imr != 0)
935 		SET(ttybits, TIOCM_LE);
936 
937 	return (ttybits);
938 }
939 
940 static int
941 cflag2modes(tcflag_t cflag, u_char *mode1p, u_char *mode2p)
942 {
943 	u_char mode1;
944 	u_char mode2;
945 	int err = 0;
946 
947 	mode1 = mode2 = 0;
948 
949 	switch (ISSET(cflag, CSIZE)) {
950 	case CS7:
951 		mode1 |= 2;			/* XXX */
952 		break;
953 	default:
954 		err = -1;
955 		/* FALLTHRU for sanity */
956 	case CS8:
957 		mode1 |= 3;			/* XXX */
958 		break;
959 	}
960 	if (!ISSET(cflag, PARENB))
961 		mode1 |= 2 << 3;
962 	else {
963 		mode1 |= 0 << 3;
964 		if (ISSET(cflag, PARODD))
965 			mode1 |= 1 << 2;
966 	}
967 
968 	if (ISSET(cflag, CSTOPB))
969 		mode2 |= 1 << 3;		/* two stop bits XXX not std */
970 
971 	if (ISSET(cflag, CRTSCTS)) {
972 		mode1 |= 1 << 7;
973 		mode2 |= 1 << 4;
974 	}
975 
976 	*mode1p = mode1;
977 	*mode2p = mode2;
978 	return (err);
979 }
980 
981 int
982 sbscn_param(struct tty *tp, struct termios *t)
983 {
984 	struct sbscn_softc *sc = device_lookup_private(&sbscn_cd, SBSCN_UNIT(tp->t_dev));
985 	struct sbscn_channel *ch = &sc->sc_channels[SBSCN_CHAN(tp->t_dev)];
986 	long brc;
987 	u_char mode1, mode2;
988 	int s;
989 
990 /* XXX reset to console parameters if console? */
991 #if 0
992 XXX disable, enable.
993 #endif
994 
995 	/* Check requested parameters. */
996 	if (sbscn_speed(t->c_ospeed, &brc) < 0)
997 		return (EINVAL);
998 	if (t->c_ispeed && t->c_ispeed != t->c_ospeed)
999 		return (EINVAL);
1000 
1001 	/*
1002 	 * For the console, always force CLOCAL and !HUPCL, so that the port
1003 	 * is always active.
1004 	 */
1005 	if (ISSET(ch->ch_swflags, TIOCFLAG_SOFTCAR) ||
1006 	    ISSET(ch->ch_hwflags, SBSCN_HW_CONSOLE)) {
1007 		SET(t->c_cflag, CLOCAL);
1008 		CLR(t->c_cflag, HUPCL);
1009 	}
1010 
1011 	/*
1012 	 * If there were no changes, don't do anything.  This avoids dropping
1013 	 * input and improves performance when all we did was frob things like
1014 	 * VMIN and VTIME.
1015 	 */
1016 	if (tp->t_ospeed == t->c_ospeed &&
1017 	    tp->t_cflag == t->c_cflag)
1018 		return (0);
1019 
1020 	if (cflag2modes(t->c_cflag, &mode1, &mode2) < 0)
1021 		return (EINVAL);
1022 
1023 	s = splserial();
1024 
1025 	ch->ch_mode1 = mode1;
1026 	ch->ch_mode2 = mode2;
1027 
1028 	/*
1029 	 * If we're not in a mode that assumes a connection is present, then
1030 	 * ignore carrier changes.
1031 	 */
1032 	if (ISSET(t->c_cflag, CLOCAL | MDMBUF))
1033 		ch->ch_i_dcd = 0;
1034 	else
1035 		ch->ch_i_dcd = ch->ch_i_dcd_pin;
1036 	/*
1037 	 * Set the flow control pins depending on the current flow control
1038 	 * mode.
1039 	 */
1040 	if (ISSET(t->c_cflag, CRTSCTS)) {
1041 		ch->ch_o_dtr = ch->ch_o_dtr_pin;
1042 		ch->ch_o_rts = ch->ch_o_rts_pin;
1043 		ch->ch_i_cts = ch->ch_i_cts_pin;
1044 		/* hw controle enable bits in mod regs set by cflag2modes */
1045 	} else if (ISSET(t->c_cflag, MDMBUF)) {
1046 		/*
1047 		 * For DTR/DCD flow control, make sure we don't toggle DTR for
1048 		 * carrier detection.
1049 		 */
1050 		ch->ch_o_dtr = 0;
1051 		ch->ch_o_rts = ch->ch_o_dtr_pin;
1052 		ch->ch_i_cts = ch->ch_i_dcd_pin;
1053 	} else {
1054 		/*
1055 		 * If no flow control, then always set RTS.  This will make
1056 		 * the other side happy if it mistakenly thinks we're doing
1057 		 * RTS/CTS flow control.
1058 		 */
1059 		ch->ch_o_dtr = ch->ch_o_dtr_pin | ch->ch_o_rts_pin;
1060 		ch->ch_o_rts = 0;
1061 		ch->ch_i_cts = 0;
1062 		if (ISSET(ch->ch_oports, ch->ch_o_dtr_pin))
1063 			SET(ch->ch_oports, ch->ch_o_rts_pin);
1064 		else
1065 			CLR(ch->ch_oports, ch->ch_o_rts_pin);
1066 	}
1067 	/* XXX maybe mask the ports which generate intrs? */
1068 
1069 	ch->ch_brc = brc;
1070 
1071 	/* XXX maybe set fifo-full receive mode if RTSCTS and high speed? */
1072 
1073 	/* And copy to tty. */
1074 	tp->t_ispeed = 0;
1075 	tp->t_ospeed = t->c_ospeed;
1076 	tp->t_cflag = t->c_cflag;
1077 
1078 	if (!ch->ch_heldchange) {
1079 		if (ch->ch_tx_busy) {
1080 			ch->ch_heldtbc = ch->ch_tbc;
1081 			ch->ch_tbc = 0;
1082 			ch->ch_heldchange = 1;
1083 		} else
1084 			sbscn_loadchannelregs(ch);
1085 	}
1086 
1087 	if (!ISSET(t->c_cflag, CHWFLOW)) {
1088 		/* Disable the high water mark. */
1089 		ch->ch_r_hiwat = 0;
1090 		ch->ch_r_lowat = 0;
1091 		if (ISSET(ch->ch_rx_flags, RX_TTY_OVERFLOWED)) {
1092 			CLR(ch->ch_rx_flags, RX_TTY_OVERFLOWED);
1093 			sbscn_schedrx(ch);
1094 		}
1095 		if (ISSET(ch->ch_rx_flags, RX_TTY_BLOCKED|RX_IBUF_BLOCKED)) {
1096 			CLR(ch->ch_rx_flags, RX_TTY_BLOCKED|RX_IBUF_BLOCKED);
1097 			sbscn_dohwiflow(ch);
1098 		}
1099 	} else {
1100 		ch->ch_r_hiwat = sbscn_rbuf_hiwat;
1101 		ch->ch_r_lowat = sbscn_rbuf_lowat;
1102 	}
1103 
1104 	splx(s);
1105 
1106 	/*
1107 	 * Update the tty layer's idea of the carrier bit, in case we changed
1108 	 * CLOCAL or MDMBUF.  We don't hang up here; we only do that by
1109 	 * explicit request.
1110 	 */
1111 	(void) (*tp->t_linesw->l_modem)(tp,
1112 	    ISSET(ch->ch_iports, ch->ch_i_dcd));
1113 
1114 #ifdef SBSCN_DEBUG
1115 	if (sbscn_debug)
1116 		sbscn_status(ch, "sbscnparam ");
1117 #endif
1118 
1119 	if (!ISSET(t->c_cflag, CHWFLOW)) {
1120 		if (ch->ch_tx_stopped) {
1121 			ch->ch_tx_stopped = 0;
1122 			sbscn_start(tp);
1123 		}
1124 	}
1125 
1126 	return (0);
1127 }
1128 
1129 void
1130 sbscn_iflush(struct sbscn_channel *ch)
1131 {
1132 #ifdef DIAGNOSTIC
1133 	int reg;
1134 #endif
1135 	int timo;
1136 
1137 #ifdef DIAGNOSTIC
1138 	reg = 0xffff;
1139 #endif
1140 	timo = 50000;
1141 	/* flush any pending I/O */
1142 	while (ISSET(READ_REG(ch->ch_base + 0x20), 0x01)
1143 	    && --timo)
1144 #ifdef DIAGNOSTIC
1145 		reg =
1146 #else
1147 		    (void)
1148 #endif
1149 		    READ_REG(ch->ch_base + 0x60);
1150 #ifdef DIAGNOSTIC
1151 	if (!timo)
1152 		aprint_debug_dev(ch->ch_sc->sc_dev,
1153 		    "sbscn_iflush timeout %02x\n", reg & 0xff);
1154 #endif
1155 }
1156 
1157 void
1158 sbscn_loadchannelregs(struct sbscn_channel *ch)
1159 {
1160 
1161 	/* XXXXX necessary? */
1162 	sbscn_iflush(ch);
1163 
1164 	WRITE_REG(ch->ch_imr_base, 0);
1165 
1166 // XXX disable?
1167 	WRITE_REG(ch->ch_base + 0x00, ch->ch_mode1);
1168 	WRITE_REG(ch->ch_base + 0x10, ch->ch_mode2);
1169 	WRITE_REG(ch->ch_base + 0x30, ch->ch_brc);
1170 
1171 	ch->ch_oports_active = ch->ch_oports;
1172 	SET_OUTPUT_SIGNALS(ch, ch->ch_oports_active);
1173 
1174 	WRITE_REG(ch->ch_imr_base, ch->ch_imr);
1175 }
1176 
1177 int
1178 sbscn_hwiflow(struct tty *tp, int block)
1179 {
1180 	struct sbscn_softc *sc = device_lookup_private(&sbscn_cd, SBSCN_UNIT(tp->t_dev));
1181 	struct sbscn_channel *ch = &sc->sc_channels[SBSCN_CHAN(tp->t_dev)];
1182 	int s;
1183 
1184 	if (ch->ch_o_rts == 0)
1185 		return (0);
1186 
1187 	s = splserial();
1188 	if (block) {
1189 		if (!ISSET(ch->ch_rx_flags, RX_TTY_BLOCKED)) {
1190 			SET(ch->ch_rx_flags, RX_TTY_BLOCKED);
1191 			sbscn_dohwiflow(ch);
1192 		}
1193 	} else {
1194 		if (ISSET(ch->ch_rx_flags, RX_TTY_OVERFLOWED)) {
1195 			CLR(ch->ch_rx_flags, RX_TTY_OVERFLOWED);
1196 			sbscn_schedrx(ch);
1197 		}
1198 		if (ISSET(ch->ch_rx_flags, RX_TTY_BLOCKED)) {
1199 			CLR(ch->ch_rx_flags, RX_TTY_BLOCKED);
1200 			sbscn_dohwiflow(ch);
1201 		}
1202 	}
1203 	splx(s);
1204 	return (1);
1205 }
1206 
1207 /*
1208  * (un)block input via hw flowcontrol
1209  */
1210 void
1211 sbscn_dohwiflow(struct sbscn_channel *ch)
1212 {
1213 
1214 	if (ch->ch_o_rts == 0)
1215 		return;
1216 
1217 	if (ISSET(ch->ch_rx_flags, RX_ANY_BLOCK)) {
1218 		CLR(ch->ch_oports, ch->ch_o_rts);
1219 		CLR(ch->ch_oports_active, ch->ch_o_rts);
1220 	} else {
1221 		SET(ch->ch_oports, ch->ch_o_rts);
1222 		SET(ch->ch_oports_active, ch->ch_o_rts);
1223 	}
1224 	SET_OUTPUT_SIGNALS(ch, ch->ch_oports_active);
1225 }
1226 
1227 void
1228 sbscn_start(struct tty *tp)
1229 {
1230 	struct sbscn_softc *sc = device_lookup_private(&sbscn_cd, SBSCN_UNIT(tp->t_dev));
1231 	struct sbscn_channel *ch = &sc->sc_channels[SBSCN_CHAN(tp->t_dev)];
1232 	int s;
1233 
1234 	s = spltty();
1235 	if (ISSET(tp->t_state, TS_BUSY | TS_TIMEOUT | TS_TTSTOP))
1236 		goto out;
1237 	if (ch->ch_tx_stopped)
1238 		goto out;
1239 	if (!ttypull(tp))
1240 		goto out;
1241 
1242 	/* Grab the first contiguous region of buffer space. */
1243 	{
1244 		u_char *tba;
1245 		int tbc;
1246 
1247 		tba = tp->t_outq.c_cf;
1248 		tbc = ndqb(&tp->t_outq, 0);
1249 
1250 		(void)splserial();
1251 
1252 		ch->ch_tba = tba;
1253 		ch->ch_tbc = tbc;
1254 	}
1255 
1256 	SET(tp->t_state, TS_BUSY);
1257 	ch->ch_tx_busy = 1;
1258 
1259 	/* Enable transmit completion interrupts if necessary. */
1260 	if (!ISSET(ch->ch_imr, 0x1)) {
1261 		SET(ch->ch_imr, 0x1);
1262 		WRITE_REG(ch->ch_imr_base, ch->ch_imr);
1263 	}
1264 
1265 	/* Output the first chunk of the contiguous buffer. */
1266 	{
1267 		u_char c;
1268 
1269 		while (ch->ch_tbc && READ_REG(ch->ch_base + 0x20) & 0x04) {
1270 			c = *ch->ch_tba++;
1271 			ch->ch_tbc--;
1272 			WRITE_REG(ch->ch_base + 0x70, c);
1273 		}
1274 	}
1275 out:
1276 	splx(s);
1277 	return;
1278 }
1279 
1280 /*
1281  * Stop output on a line.
1282  */
1283 void
1284 sbscnstop(struct tty *tp, int flag)
1285 {
1286 	struct sbscn_softc *sc = device_lookup_private(&sbscn_cd, SBSCN_UNIT(tp->t_dev));
1287 	struct sbscn_channel *ch = &sc->sc_channels[SBSCN_CHAN(tp->t_dev)];
1288 	int s;
1289 
1290 	s = splserial();
1291 	if (ISSET(tp->t_state, TS_BUSY)) {
1292 		/* Stop transmitting at the next chunk. */
1293 		ch->ch_tbc = 0;
1294 		ch->ch_heldtbc = 0;
1295 		if (!ISSET(tp->t_state, TS_TTSTOP))
1296 			SET(tp->t_state, TS_FLUSH);
1297 	}
1298 	splx(s);
1299 }
1300 
1301 void
1302 sbscn_diag(void *arg)
1303 {
1304 	struct sbscn_channel *ch = arg;
1305 	struct sbscn_softc *sc = ch->ch_sc;
1306 	int overflows, floods;
1307 	int s;
1308 
1309 	s = splserial();
1310 	overflows = ch->ch_overflows;
1311 	ch->ch_overflows = 0;
1312 	floods = ch->ch_floods;
1313 	ch->ch_floods = 0;
1314 	ch->ch_errors = 0;
1315 	splx(s);
1316 
1317 	log(LOG_WARNING, "%s: channel %d: %d fifo overflow%s, %d ibuf flood%s\n",
1318 	    device_xname(sc->sc_dev), ch->ch_num,
1319 	    overflows, overflows == 1 ? "" : "s",
1320 	    floods, floods == 1 ? "" : "s");
1321 }
1322 
1323 integrate void
1324 sbscn_rxsoft(struct sbscn_channel *ch, struct tty *tp)
1325 {
1326 	int (*rint)(int, struct tty *) = tp->t_linesw->l_rint;
1327 	u_char *get, *end;
1328 	u_int cc, scc;
1329 	u_char sr;
1330 	int code;
1331 	int s;
1332 
1333 	end = ch->ch_ebuf;
1334 	get = ch->ch_rbget;
1335 	scc = cc = sbscn_rbuf_size - ch->ch_rbavail;
1336 
1337 	if (cc == sbscn_rbuf_size) {
1338 		ch->ch_floods++;
1339 		if (ch->ch_errors++ == 0)
1340 			callout_reset(&ch->ch_diag_callout, 60 * hz,
1341 			    sbscn_diag, ch);
1342 	}
1343 
1344 	while (cc) {
1345 		code = get[0];
1346 		sr = get[1];
1347 		if (ISSET(sr, 0xf0)) {
1348 			if (ISSET(sr, 0x10)) {
1349 				ch->ch_overflows++;
1350 				if (ch->ch_errors++ == 0)
1351 					callout_reset(&ch->ch_diag_callout,
1352 					    60 * hz, sbscn_diag, ch);
1353 			}
1354 			if (ISSET(sr, 0xc0))
1355 				SET(code, TTY_FE);
1356 			if (ISSET(sr, 0x20))
1357 				SET(code, TTY_PE);
1358 		}
1359 		if ((*rint)(code, tp) == -1) {
1360 			/*
1361 			 * The line discipline's buffer is out of space.
1362 			 */
1363 			if (!ISSET(ch->ch_rx_flags, RX_TTY_BLOCKED)) {
1364 				/*
1365 				 * We're either not using flow control, or the
1366 				 * line discipline didn't tell us to block for
1367 				 * some reason.  Either way, we have no way to
1368 				 * know when there's more space available, so
1369 				 * just drop the rest of the data.
1370 				 */
1371 				get += cc << 1;
1372 				if (get >= end)
1373 					get -= sbscn_rbuf_size << 1;
1374 				cc = 0;
1375 			} else {
1376 				/*
1377 				 * Don't schedule any more receive processing
1378 				 * until the line discipline tells us there's
1379 				 * space available (through comhwiflow()).
1380 				 * Leave the rest of the data in the input
1381 				 * buffer.
1382 				 */
1383 				SET(ch->ch_rx_flags, RX_TTY_OVERFLOWED);
1384 			}
1385 			break;
1386 		}
1387 		get += 2;
1388 		if (get >= end)
1389 			get = ch->ch_rbuf;
1390 		cc--;
1391 	}
1392 
1393 	if (cc != scc) {
1394 		ch->ch_rbget = get;
1395 		s = splserial();
1396 		cc = ch->ch_rbavail += scc - cc;
1397 		/* Buffers should be ok again, release possible block. */
1398 		if (cc >= ch->ch_r_lowat) {
1399 			if (ISSET(ch->ch_rx_flags, RX_IBUF_OVERFLOWED)) {
1400 				CLR(ch->ch_rx_flags, RX_IBUF_OVERFLOWED);
1401 				SET(ch->ch_imr, 0x02);
1402 				WRITE_REG(ch->ch_imr_base, ch->ch_imr);
1403 			}
1404 			if (ISSET(ch->ch_rx_flags, RX_IBUF_BLOCKED)) {
1405 				CLR(ch->ch_rx_flags, RX_IBUF_BLOCKED);
1406 				sbscn_dohwiflow(ch);
1407 			}
1408 		}
1409 		splx(s);
1410 	}
1411 }
1412 
1413 integrate void
1414 sbscn_txsoft(struct sbscn_channel *ch, struct tty *tp)
1415 {
1416 
1417 	CLR(tp->t_state, TS_BUSY);
1418 	if (ISSET(tp->t_state, TS_FLUSH))
1419 		CLR(tp->t_state, TS_FLUSH);
1420 	else
1421 		ndflush(&tp->t_outq, (int)(ch->ch_tba - tp->t_outq.c_cf));
1422 	(*tp->t_linesw->l_start)(tp);
1423 }
1424 
1425 integrate void
1426 sbscn_stsoft(struct sbscn_channel *ch, struct tty *tp)
1427 {
1428 	u_char iports, delta;
1429 	int s;
1430 
1431 	s = splserial();
1432 	iports = ch->ch_iports;
1433 	delta = ch->ch_iports_delta;
1434 	ch->ch_iports_delta = 0;
1435 	splx(s);
1436 
1437 	if (ISSET(delta, ch->ch_i_dcd)) {
1438 		/*
1439 		 * Inform the tty layer that carrier detect changed.
1440 		 */
1441 		(void) (*tp->t_linesw->l_modem)(tp,
1442 		    ISSET(iports, ch->ch_i_dcd));
1443 	}
1444 
1445 	if (ISSET(delta, ch->ch_i_cts)) {
1446 		/* Block or unblock output according to flow control. */
1447 		if (ISSET(iports, ch->ch_i_cts)) {
1448 			ch->ch_tx_stopped = 0;
1449 			(*tp->t_linesw->l_start)(tp);
1450 		} else {
1451 			ch->ch_tx_stopped = 1;
1452 		}
1453 	}
1454 
1455 #ifdef SBSCN_DEBUG
1456 	if (sbscn_debug)
1457 		sbscn_status(ch, "sbscn_stsoft");
1458 #endif
1459 }
1460 
1461 void
1462 sbscn_soft(void *arg)
1463 {
1464 	struct sbscn_channel *ch = arg;
1465 	struct tty *tp = ch->ch_tty;
1466 
1467 	if (ch->ch_rx_ready) {
1468 		ch->ch_rx_ready = 0;
1469 		sbscn_rxsoft(ch, tp);
1470 	}
1471 
1472 	if (ch->ch_st_check) {
1473 		ch->ch_st_check = 0;
1474 		sbscn_stsoft(ch, tp);
1475 	}
1476 
1477 	if (ch->ch_tx_done) {
1478 		ch->ch_tx_done = 0;
1479 		sbscn_txsoft(ch, tp);
1480 	}
1481 }
1482 
1483 void
1484 sbscn_intr(void *arg, uint32_t status, vaddr_t pc)
1485 {
1486 	struct sbscn_channel *ch = arg;
1487 	u_char *put, *end;
1488 	u_int cc;
1489 	u_char isr, sr;
1490 
1491 	/* read ISR */
1492 	isr = READ_REG(ch->ch_isr_base) & ch->ch_imr;
1493 	if (isr == 0)
1494 		return;
1495 
1496 	end = ch->ch_ebuf;
1497 	put = ch->ch_rbput;
1498 	cc = ch->ch_rbavail;
1499 
1500 	do {
1501 		u_char	iports, delta;
1502 
1503 		if (isr & 0x02) {
1504 
1505 			sr = READ_REG(ch->ch_base + 0x20);
1506 			/* XXX sr 0x01 bit must be set at this point */
1507 
1508 #if defined(DDB) || defined(KGDB)
1509 			if ((sr & 0x80) == 0x80) {
1510 #ifdef DDB
1511 				if (ISSET(ch->ch_hwflags, SBSCN_HW_CONSOLE)) {
1512 					(void)READ_REG(ch->ch_base + 0x60);
1513 					console_debugger();
1514 					continue;
1515 				}
1516 #endif
1517 #ifdef KGDB
1518 				if (ISSET(ch->ch_hwflags, SBSCN_HW_KGDB)) {
1519 					(void)READ_REG(ch->ch_base + 0x60);
1520 					kgdb_connect(1);
1521 					continue;
1522 				}
1523 #endif
1524 			}
1525 #endif /* DDB || KGDB */
1526 
1527 		    	if (!ISSET(ch->ch_rx_flags, RX_IBUF_OVERFLOWED)) {
1528 				while (cc > 0) {
1529 					put[0] = READ_REG(ch->ch_base + 0x60);
1530 					put[1] = sr;
1531 					put += 2;
1532 					if (put >= end)
1533 						put = ch->ch_rbuf;
1534 					cc--;
1535 
1536 					sr = READ_REG(ch->ch_base + 0x20);
1537 					if (!ISSET(sr, 0x02))
1538 						break;
1539 				}
1540 
1541 				/*
1542 				 * Current string of incoming characters ended
1543 				 * because no more data was available or we
1544 				 * ran out of space.  Schedule a receive event
1545 				 * if any data was received.  If we're out of
1546 				 * space, turn off receive interrupts.
1547 				 */
1548 				ch->ch_rbput = put;
1549 				ch->ch_rbavail = cc;
1550 				if (!ISSET(ch->ch_rx_flags, RX_TTY_OVERFLOWED))
1551 					ch->ch_rx_ready = 1;
1552 
1553 				/*
1554 				 * See if we are in danger of overflowing a
1555 				 * buffer. If so, use hardware flow control
1556 				 * to ease the pressure.
1557 				 */
1558 				if (!ISSET(ch->ch_rx_flags, RX_IBUF_BLOCKED) &&
1559 				    cc < ch->ch_r_hiwat) {
1560 					SET(ch->ch_rx_flags, RX_IBUF_BLOCKED);
1561 					sbscn_dohwiflow(ch);
1562 				}
1563 
1564 				/*
1565 				 * If we're out of space, disable receive
1566 				 * interrupts until the queue has drained
1567 				 * a bit.
1568 				 */
1569 				if (!cc) {
1570 					SET(ch->ch_rx_flags,
1571 					    RX_IBUF_OVERFLOWED);
1572 					CLR(ch->ch_imr, 0x02);
1573 					WRITE_REG(ch->ch_imr_base, ch->ch_imr);
1574 				}
1575 			} else {
1576 				/* XXX panic? */
1577 				CLR(ch->ch_imr, 0x02);
1578 				WRITE_REG(ch->ch_imr_base, ch->ch_imr);
1579 				continue;
1580 			}
1581 		}
1582 
1583 		if (isr & 0x01) {
1584 			CLR(ch->ch_imr, 0x01);
1585 			WRITE_REG(ch->ch_imr_base, ch->ch_imr);
1586 		}
1587 
1588 #if 0
1589 XXX
1590 		if (isr & 0x08) {
1591 			clear input signal change!
1592 		}
1593 #endif
1594 		iports = GET_INPUT_SIGNALS(ch);
1595 		delta = iports ^ ch->ch_iports;
1596 		ch->ch_iports = iports;
1597 
1598 		/*
1599 		 * Process normal status changes
1600 		 */
1601 		if (ISSET(delta, ch->ch_i_mask)) {
1602 			SET(ch->ch_iports_delta, delta);
1603 
1604 			/*
1605 			 * Stop output immediately if we lose the output
1606 			 * flow control signal or carrier detect.
1607 			 */
1608 			if (ISSET(~iports, ch->ch_i_mask)) {
1609 				ch->ch_tbc = 0;
1610 				ch->ch_heldtbc = 0;
1611 #ifdef SBSCN_DEBUG
1612 				if (sbscn_debug)
1613 					sbscn_status(ch, "sbscn_intr  ");
1614 #endif
1615 			}
1616 
1617 			ch->ch_st_check = 1;
1618 		}
1619 	} while ((isr = (READ_REG(ch->ch_isr_base) & ch->ch_imr)) != 0);
1620 
1621 	/*
1622 	 * Done handling any receive interrupts and status changes, and
1623 	 * clearing the tx-ready interrupt if it was set.  See if data can
1624 	 * be transmitted as well. Schedule tx done event if no data left
1625 	 * and tty was marked busy.
1626 	 */
1627 	sr = READ_REG(ch->ch_base + 0x20);
1628 	if (ISSET(sr, 0x4)) {
1629 
1630 		/*
1631 		 * If we've delayed a parameter change, do it now, and restart
1632 		 * output.
1633 		 */
1634 		if (ch->ch_heldchange) {
1635 			sbscn_loadchannelregs(ch);
1636 			ch->ch_heldchange = 0;
1637 			ch->ch_tbc = ch->ch_heldtbc;
1638 			ch->ch_heldtbc = 0;
1639 		}
1640 
1641 		/* Output the next chunk of the contiguous buffer, if any. */
1642 		if (ch->ch_tbc > 0) {
1643 			int wrote1;
1644 			u_char c;
1645 
1646 			wrote1 = 0;
1647 			while (ch->ch_tbc &&
1648 			    READ_REG(ch->ch_base + 0x20) & 0x04) {
1649 				wrote1 = 1;
1650 				c = *ch->ch_tba++;
1651 				ch->ch_tbc--;
1652 				WRITE_REG(ch->ch_base + 0x70, c);
1653 			}
1654 			if (wrote1) {
1655 				SET(ch->ch_imr, 0x01);
1656 				WRITE_REG(ch->ch_imr_base, ch->ch_imr);
1657 			}
1658 		} else {
1659 			/*
1660 			 * transmit completion interrupts already disabled,
1661 			 * mark the channel tx state as done.
1662 			 */
1663 			if (ch->ch_tx_busy) {
1664 				ch->ch_tx_busy = 0;
1665 				ch->ch_tx_done = 1;
1666 			}
1667 		}
1668 	}
1669 
1670 	/* Wake up the poller. */
1671 	softint_schedule(ch->ch_si);
1672 
1673 #ifdef RND_SBSCN
1674 	rnd_add_uint32(&ch->ch_rnd_source, isr | sr);
1675 #endif
1676 }
1677 
1678 /*
1679  * The following functions are polled getc and putc routines, shared
1680  * by the console and kgdb glue.
1681  */
1682 
1683 int
1684 sbscn_common_getc(u_long addr, int chan)
1685 {
1686 	int s = splhigh();
1687 	u_long base = MIPS_PHYS_TO_KSEG1(addr + (chan * 0x100));
1688 	int c;
1689 
1690 	/* block until a character becomes available */
1691 	while ((READ_REG(base + 0x20) & 0x01) == 0)
1692 		continue;
1693 
1694 	c = READ_REG(base + 0x60) & 0xff;
1695 	splx(s);
1696 	return (c);
1697 }
1698 
1699 void
1700 sbscn_common_putc(u_long addr, int chan, int c)
1701 {
1702 	int s = splhigh();
1703 	int timo;
1704 	u_long base = MIPS_PHYS_TO_KSEG1(addr + (chan * 0x100));
1705 
1706 	/* wait for any pending transmission to finish */
1707 	timo = 1500000;
1708 	while ((READ_REG(base + 0x20) & 0x08) == 0 && --timo)
1709 		continue;
1710 
1711 	WRITE_REG(base + 0x70, c);
1712 
1713 	/* wait for this transmission to complete */
1714 	timo = 15000000;
1715 	while ((READ_REG(base + 0x20) & 0x08) == 0 && --timo)
1716 		continue;
1717 
1718 	splx(s);
1719 }
1720 
1721 /*
1722  * Initialize UART for use as console or KGDB line.
1723  */
1724 int
1725 sbscn_init(u_long addr, int chan, int rate, tcflag_t cflag)
1726 {
1727 #if 1
1728 	u_long chanregbase = MIPS_PHYS_TO_KSEG1(addr + (chan * 0x100));
1729 	u_long imaskreg = MIPS_PHYS_TO_KSEG1(addr + 0x230 + (chan * 0x20));
1730 	u_char mode1, mode2;
1731 	u_long brc;
1732 	volatile int timo;
1733 
1734 	WRITE_REG(imaskreg, 0);			/* disable channel intrs */
1735 
1736 	/* XXX should we really do the following?  how about only if enabled? */
1737 	/* wait for any pending transmission to finish */
1738 	timo = 1500000;
1739 	while ((READ_REG(chanregbase + 0x20) & 0x08) == 0 && --timo)
1740 		continue;
1741 
1742 	/* XXX: wait a little.  THIS SHOULD NOT BE NECESSARY!!! (?) */
1743 	timo = 1500000;
1744 	while (--timo)
1745 		;
1746 
1747 	WRITE_REG(chanregbase + 0x50, 2 << 4);	/* reset receiver */
1748 	WRITE_REG(chanregbase + 0x50, 3 << 4);	/* reset transmitter */
1749 
1750 	/* set up the line for use */
1751 	(void)cflag2modes(cflag, &mode1, &mode2);
1752 	(void)sbscn_speed(rate, &brc);
1753 	WRITE_REG(chanregbase + 0x00, mode1);
1754 	WRITE_REG(chanregbase + 0x10, mode2);
1755 	WRITE_REG(chanregbase + 0x30, brc);
1756 
1757 	/* enable transmit and receive */
1758 #define	M_DUART_RX_EN			0x01
1759 #define	M_DUART_TX_EN			0x04
1760 	WRITE_REG(chanregbase + 0x50,M_DUART_RX_EN | M_DUART_TX_EN);
1761 #endif
1762 
1763 	/* XXX: wait a little.  THIS SHOULD NOT BE NECESSARY!!! (?) */
1764 	timo = 1500000;
1765 	while (--timo)
1766 		;
1767 
1768 #if 0 /* XXXCGD */
1769 	bus_space_handle_t ioh;
1770 
1771 	if (bus_space_map(iot, iobase, COM_NPORTS, 0, &ioh))
1772 		return (ENOMEM); /* ??? */
1773 
1774 	bus_space_write_1(iot, ioh, com_lcr, LCR_EERS);
1775 	bus_space_write_1(iot, ioh, com_efr, 0);
1776 	bus_space_write_1(iot, ioh, com_lcr, LCR_DLAB);
1777 	rate = comspeed(rate, frequency);
1778 	bus_space_write_1(iot, ioh, com_dlbl, rate);
1779 	bus_space_write_1(iot, ioh, com_dlbh, rate >> 8);
1780 	bus_space_write_1(iot, ioh, com_lcr, cflag2lcr(cflag));
1781 	bus_space_write_1(iot, ioh, com_mcr, MCR_DTR | MCR_RTS);
1782 	bus_space_write_1(iot, ioh, com_fifo,
1783 	    FIFO_ENABLE | FIFO_RCV_RST | FIFO_XMT_RST | FIFO_TRIGGER_1);
1784 	bus_space_write_1(iot, ioh, com_ier, 0);
1785 
1786 	*iohp = ioh;
1787 	return (0);
1788 #endif /* XXXCGD */
1789 	/* XXXCGD */
1790 	return (0);
1791 }
1792 
1793 /*
1794  * Following are all routines needed for sbscn to act as console
1795  */
1796 int
1797 sbscn_cnattach(u_long addr, int chan, int rate, tcflag_t cflag)
1798 {
1799 	int res;
1800 	static struct consdev sbscn_cons = {
1801 		NULL, NULL, sbscn_cngetc, sbscn_cnputc, sbscn_cnpollc, NULL,
1802 		    NULL, NULL, NODEV, CN_NORMAL
1803 	};
1804 
1805 	res = sbscn_init(addr, chan, rate, cflag);
1806 	if (res)
1807 		return (res);
1808 
1809 	cn_tab = &sbscn_cons;
1810 
1811 	sbscn_cons_present = 1;
1812 	sbscn_cons_addr = addr;
1813 	sbscn_cons_chan = chan;
1814 	sbscn_cons_rate = rate;
1815 	sbscn_cons_cflag = cflag;
1816 
1817 	return (0);
1818 }
1819 
1820 int
1821 sbscn_cngetc(dev_t dev)
1822 {
1823 
1824 	return (sbscn_common_getc(sbscn_cons_addr, sbscn_cons_chan));
1825 }
1826 
1827 /*
1828  * Console kernel output character routine.
1829  */
1830 void
1831 sbscn_cnputc(dev_t dev, int c)
1832 {
1833 
1834 	sbscn_common_putc(sbscn_cons_addr, sbscn_cons_chan, c);
1835 }
1836 
1837 void
1838 sbscn_cnpollc(dev_t dev, int on)
1839 {
1840 
1841 }
1842 
1843 #ifdef KGDB
1844 int
1845 sbscn_kgdb_attach(u_long addr, int chan, int rate, tcflag_t cflag)
1846 {
1847 	int res;
1848 
1849 	if (!sbscn_cons_present &&
1850 	    sbscn_cons_addr == addr && sbscn_cons_chan == chan)
1851 		return (EBUSY); /* cannot share with console */
1852 
1853 	res = sbscn_init(addr, chan, rate, cflag);
1854 	if (res)
1855 		return (res);
1856 
1857 	kgdb_attach(sbscn_kgdb_getc, sbscn_kgdb_putc, NULL);
1858 	kgdb_dev = 123; /* unneeded, only to satisfy some tests */
1859 
1860 	sbscn_kgdb_present = 1;
1861 	sbscn_kgdb_addr = addr;
1862 	sbscn_kgdb_chan = chan;
1863 
1864 	return (0);
1865 }
1866 
1867 /* ARGSUSED */
1868 int
1869 sbscn_kgdb_getc(void *arg)
1870 {
1871 
1872 	return (sbscn_common_getc(sbscn_kgdb_addr, sbscn_kgdb_chan));
1873 }
1874 
1875 /* ARGSUSED */
1876 void
1877 sbscn_kgdb_putc(void *arg, int c)
1878 {
1879 
1880 	sbscn_common_getc(sbscn_kgdb_addr, sbscn_kgdb_chan, c);
1881 }
1882 #endif /* KGDB */
1883 
1884 /*
1885  * helper function to identify the sbscn channels used by
1886  * console or KGDB (and not yet autoconf attached)
1887  */
1888 int
1889 sbscn_is_console(u_long addr, int chan)
1890 {
1891 
1892 	if (sbscn_cons_present && !sbscn_cons_attached &&
1893 	    sbscn_cons_addr == addr && sbscn_cons_chan == chan)
1894 		return (1);
1895 #ifdef KGDB
1896 	if (sbscn_kgdb_present && !sbscn_kgdb_attached &&
1897 	    sbscn_kgdb_addr == addr && sbscn_kgdb_chan == chan)
1898 		return (1);
1899 #endif
1900 	return (0);
1901 }
1902