xref: /netbsd-src/sys/arch/mips/sibyte/dev/sbjcn.c (revision a5847cc334d9a7029f6352b847e9e8d71a0f9e0c)
1 /* $NetBSD: sbjcn.c,v 1.28 2011/07/10 23:32:03 matt 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  * `sbjcn' driver, supports console over SiByte SB-1250 JTAG.
99  *
100  *  Accesses a section of JTAG memory space to mimic a console,
101  *  if there's a matching program outside to communicate with.
102  *  If nobody is there, things will be very quiet.
103  */
104 
105 #include <sys/cdefs.h>
106 __KERNEL_RCSID(0, "$NetBSD: sbjcn.c,v 1.28 2011/07/10 23:32:03 matt Exp $");
107 
108 #define	SBJCN_DEBUG
109 
110 #include "opt_ddb.h"
111 #include "ioconf.h"
112 
113 #include <sys/param.h>
114 #include <sys/systm.h>
115 #include <sys/ioctl.h>
116 #include <sys/select.h>
117 #include <sys/tty.h>
118 #include <sys/proc.h>
119 #include <sys/conf.h>
120 #include <sys/file.h>
121 #include <sys/uio.h>
122 #include <sys/kernel.h>
123 #include <sys/syslog.h>
124 #include <sys/types.h>
125 #include <sys/device.h>
126 #include <sys/malloc.h>
127 #include <sys/vnode.h>
128 #include <sys/kauth.h>
129 
130 #include <sbmips/dev/sbscd/sbscdvar.h>
131 #include <sbmips/dev/sbscd/sbjcnvar.h>
132 
133 #include <dev/cons.h>
134 
135 #include <mips/locore.h>
136 
137 void	sbjcn_attach_channel(struct sbjcn_softc *sc, int chan, int intr);
138 static void sbjcncn_grabdword(struct sbjcn_channel *ch);
139 static char sbjcncn_nextbyte(struct sbjcn_channel *ch);
140 static void sbjcn_cngrabdword(void);
141 
142 #if defined(DDB) || defined(KGDB)
143 static void sbjcn_enable_debugport(struct sbjcn_channel *ch);
144 #endif
145 void	sbjcn_config(struct sbjcn_channel *ch);
146 void	sbjcn_shutdown(struct sbjcn_channel *ch);
147 int	sbjcn_speed(long, long *);
148 static int cflag2modes(tcflag_t, u_char *, u_char *);
149 int	sbjcn_param(struct tty *, struct termios *);
150 void	sbjcn_start(struct tty *);
151 int	sbjcn_hwiflow(struct tty *, int);
152 
153 void	sbjcn_loadchannelregs(struct sbjcn_channel *);
154 void	sbjcn_dohwiflow(struct sbjcn_channel *);
155 void	sbjcn_break(struct sbjcn_channel *, int);
156 void	sbjcn_modem(struct sbjcn_channel *, int);
157 void	tiocm_to_sbjcn(struct sbjcn_channel *, int, int);
158 int	sbjcn_to_tiocm(struct sbjcn_channel *);
159 void	sbjcn_iflush(struct sbjcn_channel *);
160 
161 int	sbjcn_init(u_long addr, int chan, int rate, tcflag_t cflag);
162 int	sbjcn_common_getc(u_long addr, int chan);
163 void	sbjcn_common_putc(u_long addr, int chan, int c);
164 
165 int	sbjcn_cngetc(dev_t dev);
166 void	sbjcn_cnputc(dev_t dev, int c);
167 void	sbjcn_cnpollc(dev_t dev, int on);
168 
169 dev_type_open(sbjcnopen);
170 dev_type_close(sbjcnclose);
171 dev_type_read(sbjcnread);
172 dev_type_write(sbjcnwrite);
173 dev_type_ioctl(sbjcnioctl);
174 dev_type_stop(sbjcnstop);
175 dev_type_tty(sbjcntty);
176 
177 const struct cdevsw sbjcn_cdevsw = {
178 	sbjcnopen, sbjcnclose, sbjcnread, sbjcnwrite, sbjcnioctl,
179 	sbjcnstop, sbjcntty, nopoll, nommap, ttykqfilter, D_TTY
180 };
181 
182 #define	integrate	static inline
183 integrate void sbjcn_rxsoft(struct sbjcn_channel *, struct tty *);
184 integrate void sbjcn_txsoft(struct sbjcn_channel *, struct tty *);
185 integrate void sbjcn_stsoft(struct sbjcn_channel *, struct tty *);
186 integrate void sbjcn_schedrx(struct sbjcn_channel *);
187 integrate void sbjcn_recv(struct sbjcn_channel *ch);
188 void	sbjcn_diag(void *);
189 void	sbjcn_callout(void *);
190 
191 /*
192  * Make this an option variable one can patch.
193  * But be warned:  this must be a power of 2!
194  */
195 u_int sbjcn_rbuf_size = SBJCN_RING_SIZE;
196 
197 /* Stop input when 3/4 of the ring is full; restart when only 1/4 is full. */
198 u_int sbjcn_rbuf_hiwat = (SBJCN_RING_SIZE * 1) / 4;
199 u_int sbjcn_rbuf_lowat = (SBJCN_RING_SIZE * 3) / 4;
200 
201 static int	sbjcn_cons_present;
202 static int	sbjcn_cons_attached;
203 static u_long	sbjcn_cons_addr;
204 static int	sbjcn_cons_chan;
205 static int	sbjcn_cons_rate;
206 static tcflag_t	sbjcn_cons_cflag;
207 static int	sbjcn_cons_waiting_input;
208 static uint64_t	sbjcn_cons_input_buf;
209 
210 #ifdef KGDB
211 #include <sys/kgdb.h>
212 
213 static int	sbjcn_kgdb_present;
214 static int	sbjcn_kgdb_attached;
215 static u_long	sbjcn_kgdb_addr;
216 static int	sbjcn_kgdb_chan;
217 
218 int	sbjcn_kgdb_getc(void *);
219 void	sbjcn_kgdb_putc(void *, int);
220 #endif /* KGDB */
221 
222 static int	sbjcn_match(device_t, cfdata_t, void *);
223 static void	sbjcn_attach(device_t, device_t, void *);
224 
225 CFATTACH_DECL_NEW(sbjcn, sizeof(struct sbjcn_softc),
226     sbjcn_match, sbjcn_attach, NULL, NULL);
227 
228 #define	READ_REG(rp)		(mips3_ld((volatile uint64_t *)(rp)))
229 #define	WRITE_REG(rp, val)	(mips3_sd((volatile uint64_t *)(rp), (val)))
230 
231 #define	JTAG_CONS_CONTROL  0x00
232 #define	JTAG_CONS_INPUT    0x20
233 #define	JTAG_CONS_OUTPUT   0x40
234 #define	JTAG_CONS_MAGICNUM 0x50FABEEF12349873
235 
236 #define	jtag_input_len(data)    (((data) >> 56) & 0xFF)
237 
238 
239 static int
240 sbjcn_match(device_t parent, cfdata_t match, void *aux)
241 {
242 	struct sbscd_attach_args *sa = aux;
243 
244 	if (sa->sa_locs.sa_type != SBSCD_DEVTYPE_JTAGCONS)
245 		return (0);
246 
247 	return 1;
248 }
249 
250 static void
251 sbjcn_attach(device_t parent, device_t self, void *aux)
252 {
253 	struct sbjcn_softc *sc = device_private(self);
254 	struct sbscd_attach_args *sa = aux;
255 
256 	sc->sc_dev = self;
257 	sc->sc_addr = sa->sa_base + sa->sa_locs.sa_offset;
258 
259 	aprint_normal("\n");
260 	sbjcn_attach_channel(sc, 0, sa->sa_locs.sa_intr[0]);
261 }
262 
263 void
264 sbjcn_attach_channel(struct sbjcn_softc *sc, int chan, int intr)
265 {
266 	struct sbjcn_channel *ch = &sc->sc_channels[chan];
267 	u_long chan_addr;
268 	struct tty *tp;
269 
270 	ch->ch_sc = sc;
271 	ch->ch_num = chan;
272 
273 	chan_addr = sc->sc_addr + (0x100 * chan);
274 	ch->ch_base = (void *)MIPS_PHYS_TO_KSEG1(chan_addr);
275 	ch->ch_input_reg =
276 	    (void *)MIPS_PHYS_TO_KSEG1(sc->sc_addr + JTAG_CONS_INPUT);
277 	ch->ch_output_reg =
278 	    (void *)MIPS_PHYS_TO_KSEG1(sc->sc_addr + JTAG_CONS_OUTPUT);
279 	ch->ch_control_reg =
280 	    (void *)MIPS_PHYS_TO_KSEG1(sc->sc_addr + JTAG_CONS_CONTROL);
281 	ch->ch_waiting_input = 0;
282 
283 	ch->ch_i_dcd = ch->ch_i_dcd_pin = 0 /* XXXCGD */;
284 	ch->ch_i_cts = ch->ch_i_cts_pin = 0 /* XXXCGD */;
285 	ch->ch_i_dsr = ch->ch_i_dsr_pin = 0 /* XXXCGD */;
286 	ch->ch_i_ri = ch->ch_i_ri_pin = 0 /* XXXCGD */;
287 	ch->ch_i_mask =
288 	    ch->ch_i_dcd | ch->ch_i_cts | ch->ch_i_dsr | ch->ch_i_ri;
289 	ch->ch_o_dtr = ch->ch_o_dtr_pin = 0 /* XXXCGD */;
290 	ch->ch_o_rts = ch->ch_o_rts_pin = 0 /* XXXCGD */;
291 	ch->ch_o_mask = ch->ch_o_dtr | ch->ch_o_rts;
292 
293 	callout_init(&ch->ch_diag_callout, 0);
294 	callout_init(&ch->ch_callout, 0);
295 
296 	/* Disable interrupts before configuring the device. */
297 	ch->ch_imr = 0;
298 
299 	if (sbjcn_cons_present &&
300 	    sbjcn_cons_addr == chan_addr && sbjcn_cons_chan == chan) {
301 		sbjcn_cons_attached = 1;
302 
303 		/* Make sure the console is always "hardwired". */
304 		delay(1000);			/* wait for output to finish */
305 		SET(ch->ch_hwflags, SBJCN_HW_CONSOLE);
306 		SET(ch->ch_swflags, TIOCFLAG_SOFTCAR);
307 	}
308 
309 	tp = tty_alloc();
310 	tp->t_oproc = sbjcn_start;
311 	tp->t_param = sbjcn_param;
312 	tp->t_hwiflow = sbjcn_hwiflow;
313 
314 	ch->ch_tty = tp;
315 	ch->ch_rbuf = malloc(sbjcn_rbuf_size << 1, M_DEVBUF, M_NOWAIT);
316 	if (ch->ch_rbuf == NULL) {
317 		aprint_error_dev(sc->sc_dev,
318 		    "channel %d: unable to allocate ring buffer\n",
319 		    chan);
320 		return;
321 	}
322 	ch->ch_ebuf = ch->ch_rbuf + (sbjcn_rbuf_size << 1);
323 
324 	tty_attach(tp);
325 
326 	if (ISSET(ch->ch_hwflags, SBJCN_HW_CONSOLE)) {
327 		int maj;
328 
329 		/* locate the major number */
330 		maj = cdevsw_lookup_major(&sbjcn_cdevsw);
331 
332 		cn_tab->cn_dev = makedev(maj,
333 		    (device_unit(sc->sc_dev) << 1) + chan);
334 
335 		aprint_normal_dev(sc->sc_dev, "channel %d: %s\n",
336 		    chan, "console");
337 	}
338 
339 #ifdef KGDB
340 	/*
341 	 * Allow kgdb to "take over" this port.  If this is
342 	 * the kgdb device, it has exclusive use.
343 	 */
344 	if (sbjcn_kgdb_present &&
345 	    sbjcn_kgdb_addr == chan_addr && sbjcn_kgdb_chan == chan) {
346 		sbjcn_kgdb_attached = 1;
347 
348 		SET(ch->ch_hwflags, SBJCN_HW_KGDB);
349 		aprint_normal_dev(sc->sc_dev, "channel %d: %s\n",
350 		    chan, "kgdb");
351 	}
352 #endif
353 
354 	sbjcn_config(ch);
355 
356 	callout_reset(&ch->ch_callout, hz/10, sbjcn_callout, ch);
357 
358 	SET(ch->ch_hwflags, SBJCN_HW_DEV_OK);
359 }
360 
361 int
362 sbjcn_speed(long speed, long *brcp)
363 {
364 #define	divrnd(n, q)	(((n)*2/(q)+1)/2)	/* divide and round off */
365 
366 	int x, err;
367 	int frequency = 100000000;
368 
369 	*brcp = divrnd(frequency / 20, speed) - 1;
370 
371 	if (speed <= 0)
372 		return (-1);
373 	x = divrnd(frequency / 20, speed);
374 	if (x <= 0)
375 		return (-1);
376 	err = divrnd(((quad_t)frequency) * 1000 / 20, speed * x) - 1000;
377 	if (err < 0)
378 		err = -err;
379 	if (err > SBJCN_TOLERANCE)
380 		return (-1);
381 	*brcp = x - 1;
382 	return (0);
383 
384 #undef	divrnd
385 }
386 
387 #ifdef SBJCN_DEBUG
388 void	sbjcn_status(struct sbjcn_channel *, char *);
389 
390 int	sbjcn_debug = 1 /* XXXCGD */;
391 
392 void
393 sbjcn_status(struct sbjcn_channel *ch, char *str)
394 {
395 	struct sbjcn_softc *sc = ch->ch_sc;
396 	struct tty *tp = ch->ch_tty;
397 
398 	aprint_normal_dev(sc->sc_dev,
399 	    "chan %d: %s %sclocal  %sdcd %sts_carr_on %sdtr %stx_stopped\n",
400 	    ch->ch_num, str,
401 	    ISSET(tp->t_cflag, CLOCAL) ? "+" : "-",
402 	    ISSET(ch->ch_iports, ch->ch_i_dcd) ? "+" : "-",
403 	    ISSET(tp->t_state, TS_CARR_ON) ? "+" : "-",
404 	    ISSET(ch->ch_oports, ch->ch_o_dtr) ? "+" : "-",
405 	    ch->ch_tx_stopped ? "+" : "-");
406 
407 	aprint_normal_dev(sc->sc_dev,
408 	    "chan %d: %s %scrtscts %scts %sts_ttstop  %srts %xrx_flags\n",
409 	    ch->ch_num, str,
410 	    ISSET(tp->t_cflag, CRTSCTS) ? "+" : "-",
411 	    ISSET(ch->ch_iports, ch->ch_i_cts) ? "+" : "-",
412 	    ISSET(tp->t_state, TS_TTSTOP) ? "+" : "-",
413 	    ISSET(ch->ch_oports, ch->ch_o_rts) ? "+" : "-",
414 	    ch->ch_rx_flags);
415 }
416 #endif
417 
418 #if defined(DDB) || defined(KGDB)
419 static void
420 sbjcn_enable_debugport(struct sbjcn_channel *ch)
421 {
422 	int s;
423 
424 	/* Turn on line break interrupt, set carrier. */
425 	s = splserial();
426 
427 	ch->ch_imr = 0x04;
428 	SET(ch->ch_oports, ch->ch_o_dtr | ch->ch_o_rts);
429 
430 	splx(s);
431 }
432 #endif
433 
434 void
435 sbjcn_config(struct sbjcn_channel *ch)
436 {
437 
438 	/* Disable interrupts before configuring the device. */
439 	ch->ch_imr = 0x00;
440 
441 #ifdef DDB
442 	if (ISSET(ch->ch_hwflags, SBJCN_HW_CONSOLE))
443 		sbjcn_enable_debugport(ch);
444 #endif
445 
446 #ifdef KGDB
447 	/*
448 	 * Allow kgdb to "take over" this port.  If this is
449 	 * the kgdb device, it has exclusive use.
450 	 */
451 	if (ISSET(ch->ch_hwflags, SBJCN_HW_KGDB))
452 		sbjcn_enable_debugport(ch);
453 #endif
454 }
455 
456 void
457 sbjcn_shutdown(struct sbjcn_channel *ch)
458 {
459 	struct tty *tp = ch->ch_tty;
460 	int s;
461 
462 	s = splserial();
463 
464 	/* If we were asserting flow control, then deassert it. */
465 	SET(ch->ch_rx_flags, RX_IBUF_BLOCKED);
466 	sbjcn_dohwiflow(ch);
467 
468 	/* Clear any break condition set with TIOCSBRK. */
469 	sbjcn_break(ch, 0);
470 
471 	/*
472 	 * Hang up if necessary.  Wait a bit, so the other side has time to
473 	 * notice even if we immediately open the port again.
474 	 */
475 	if (ISSET(tp->t_cflag, HUPCL)) {
476 		sbjcn_modem(ch, 0);
477 		(void) tsleep(ch, TTIPRI, ttclos, hz);
478 	}
479 
480 	/* Turn off interrupts. */
481 #ifdef DDB
482 	if (ISSET(ch->ch_hwflags, SBJCN_HW_CONSOLE))
483 		ch->ch_imr = 0x04; /* interrupt on break */
484 	else
485 #endif
486 		ch->ch_imr = 0;
487 
488 	splx(s);
489 }
490 
491 int
492 sbjcnopen(dev_t dev, int flag, int mode, struct lwp *l)
493 {
494 	int chan = SBJCN_CHAN(dev);
495 	struct sbjcn_softc *sc;
496 	struct sbjcn_channel *ch;
497 	struct tty *tp;
498 	int s, s2;
499 	int error;
500 
501 	sc = device_lookup_private(&sbjcn_cd, SBJCN_UNIT(dev));
502 	if (sc == NULL)
503 		return (ENXIO);
504 
505 	ch = &sc->sc_channels[chan];
506 	if (!ISSET(ch->ch_hwflags, SBJCN_HW_DEV_OK) || ch->ch_rbuf == NULL)
507 		return (ENXIO);
508 
509 #ifdef KGDB
510 	/*
511 	 * If this is the kgdb port, no other use is permitted.
512 	 */
513 	if (ISSET(ch->ch_hwflags, SBJCN_HW_KGDB))
514 		return (EBUSY);
515 #endif
516 
517 	tp = ch->ch_tty;
518 
519 	if (kauth_authorize_device_tty(l->l_cred, KAUTH_DEVICE_TTY_OPEN, tp))
520 		return (EBUSY);
521 
522 	s = spltty();
523 
524 	/*
525 	 * Do the following iff this is a first open.
526 	 */
527 	if (!ISSET(tp->t_state, TS_ISOPEN) && tp->t_wopen == 0) {
528 		struct termios t;
529 
530 		tp->t_dev = dev;
531 
532 		s2 = splserial();
533 
534 		/* Turn on receive, break, and status change interrupts. */
535 		ch->ch_imr = 0xe;
536 
537 		/* Fetch the current modem control status, needed later. */
538 		ch->ch_iports = 0;
539 		ch->ch_iports_delta = 0;
540 		splx(s2);
541 
542 		/*
543 		 * Initialize the termios status to the defaults.  Add in the
544 		 * sticky bits from TIOCSFLAGS.
545 		 */
546 		t.c_ispeed = 0;
547 		if (ISSET(ch->ch_hwflags, SBJCN_HW_CONSOLE)) {
548 			t.c_ospeed = sbjcn_cons_rate;
549 			t.c_cflag = sbjcn_cons_cflag;
550 		} else {
551 			t.c_ospeed = TTYDEF_SPEED;
552 			t.c_cflag = TTYDEF_CFLAG;
553 		}
554 		if (ISSET(ch->ch_swflags, TIOCFLAG_CLOCAL))
555 			SET(t.c_cflag, CLOCAL);
556 		if (ISSET(ch->ch_swflags, TIOCFLAG_CRTSCTS))
557 			SET(t.c_cflag, CRTSCTS);
558 		if (ISSET(ch->ch_swflags, TIOCFLAG_MDMBUF))
559 			SET(t.c_cflag, MDMBUF);
560 		/* Make sure sbjcn_param() will do something. */
561 		tp->t_ospeed = 0;
562 		(void) sbjcn_param(tp, &t);
563 		tp->t_iflag = TTYDEF_IFLAG;
564 		tp->t_oflag = TTYDEF_OFLAG;
565 		tp->t_lflag = TTYDEF_LFLAG;
566 		ttychars(tp);
567 		ttsetwater(tp);
568 
569 		s2 = splserial();
570 
571 		/*
572 		 * Turn on DTR.  We must always do this, even if carrier is not
573 		 * present, because otherwise we'd have to use TIOCSDTR
574 		 * immediately after setting CLOCAL, which applications do not
575 		 * expect.  We always assert DTR while the device is open
576 		 * unless explicitly requested to deassert it.
577 		 */
578 		sbjcn_modem(ch, 1);
579 
580 		/* Clear the input ring, and unblock. */
581 		ch->ch_rbput = ch->ch_rbget = ch->ch_rbuf;
582 		ch->ch_rbavail = sbjcn_rbuf_size;
583 		sbjcn_iflush(ch);
584 		CLR(ch->ch_rx_flags, RX_ANY_BLOCK);
585 		sbjcn_dohwiflow(ch);
586 
587 #ifdef SBJCN_DEBUG
588 		if (sbjcn_debug)
589 			sbjcn_status(ch, "sbjcnopen  ");
590 #endif
591 
592 		splx(s2);
593 	}
594 
595 	splx(s);
596 
597 	error = ttyopen(tp, SBJCN_DIALOUT(dev), ISSET(flag, O_NONBLOCK));
598 	if (error)
599 		goto bad;
600 
601 	error = (*tp->t_linesw->l_open)(dev, tp);
602 	if (error)
603 		goto bad;
604 
605 	return (0);
606 
607 bad:
608 	if (!ISSET(tp->t_state, TS_ISOPEN) && tp->t_wopen == 0) {
609 		/*
610 		 * We failed to open the device, and nobody else had it opened.
611 		 * Clean up the state as appropriate.
612 		 */
613 		sbjcn_shutdown(ch);
614 	}
615 
616 	return (error);
617 }
618 
619 int
620 sbjcnclose(dev_t dev, int flag, int mode, struct proc *p)
621 {
622 	struct sbjcn_softc *sc = device_lookup_private(&sbjcn_cd, SBJCN_UNIT(dev));
623 	struct sbjcn_channel *ch = &sc->sc_channels[SBJCN_CHAN(dev)];
624 	struct tty *tp = ch->ch_tty;
625 
626 	/* XXX This is for cons.c. */
627 	if (!ISSET(tp->t_state, TS_ISOPEN))
628 		return (0);
629 
630 	(*tp->t_linesw->l_close)(tp, flag);
631 	ttyclose(tp);
632 
633 	if (!ISSET(tp->t_state, TS_ISOPEN) && tp->t_wopen == 0) {
634 		/*
635 		 * Although we got a last close, the device may still be in
636 		 * use; e.g. if this was the dialout node, and there are still
637 		 * processes waiting for carrier on the non-dialout node.
638 		 */
639 		sbjcn_shutdown(ch);
640 	}
641 
642 	return (0);
643 }
644 
645 int
646 sbjcnread(dev_t dev, struct uio *uio, int flag)
647 {
648 	struct sbjcn_softc *sc = device_lookup_private(&sbjcn_cd, SBJCN_UNIT(dev));
649 	struct sbjcn_channel *ch = &sc->sc_channels[SBJCN_CHAN(dev)];
650 	struct tty *tp = ch->ch_tty;
651 
652 	return ((*tp->t_linesw->l_read)(tp, uio, flag));
653 }
654 
655 int
656 sbjcnwrite(dev_t dev, struct uio *uio, int flag)
657 {
658 	struct sbjcn_softc *sc = device_lookup_private(&sbjcn_cd, SBJCN_UNIT(dev));
659 	struct sbjcn_channel *ch = &sc->sc_channels[SBJCN_CHAN(dev)];
660 	struct tty *tp = ch->ch_tty;
661 
662 	return ((*tp->t_linesw->l_write)(tp, uio, flag));
663 }
664 
665 struct tty *
666 sbjcntty(dev_t dev)
667 {
668 	struct sbjcn_softc *sc = device_lookup_private(&sbjcn_cd, SBJCN_UNIT(dev));
669 	struct sbjcn_channel *ch = &sc->sc_channels[SBJCN_CHAN(dev)];
670 	struct tty *tp = ch->ch_tty;
671 
672 	return (tp);
673 }
674 
675 int
676 sbjcnioctl(dev_t dev, u_long cmd, void *data, int flag, struct lwp *l)
677 {
678 	struct sbjcn_softc *sc = device_lookup_private(&sbjcn_cd, SBJCN_UNIT(dev));
679 	struct sbjcn_channel *ch = &sc->sc_channels[SBJCN_CHAN(dev)];
680 	struct tty *tp = ch->ch_tty;
681 	int error;
682 	int s;
683 
684 	error = (*tp->t_linesw->l_ioctl)(tp, cmd, data, flag, p);
685 	if (error >= 0)
686 		return (error);
687 
688 	error = ttioctl(tp, cmd, data, flag, p);
689 	if (error >= 0)
690 		return (error);
691 
692 	error = 0;
693 
694 	s = splserial();
695 
696 	switch (cmd) {
697 	case TIOCSBRK:
698 		sbjcn_break(ch, 1);
699 		break;
700 
701 	case TIOCCBRK:
702 		sbjcn_break(ch, 0);
703 		break;
704 
705 	case TIOCSDTR:
706 		sbjcn_modem(ch, 1);
707 		break;
708 
709 	case TIOCCDTR:
710 		sbjcn_modem(ch, 0);
711 		break;
712 
713 	case TIOCGFLAGS:
714 		*(int *)data = ch->ch_swflags;
715 		break;
716 
717 	case TIOCSFLAGS:
718 		error = kauth_authorize_device_tty(l->l_cred,
719 		    KAUTH_DEVICE_TTY_PRIVSET, tp);
720 		if (error)
721 			break;
722 		ch->ch_swflags = *(int *)data;
723 		break;
724 
725 	case TIOCMSET:
726 	case TIOCMBIS:
727 	case TIOCMBIC:
728 		tiocm_to_sbjcn(ch, cmd, *(int *)data);
729 		break;
730 
731 	case TIOCMGET:
732 		*(int *)data = sbjcn_to_tiocm(ch);
733 		break;
734 
735 	default:
736 		error = ENOTTY;
737 		break;
738 	}
739 
740 	splx(s);
741 
742 #ifdef SBJCN_DEBUG
743 	if (sbjcn_debug)
744 		sbjcn_status(ch, "sbjcn_ioctl ");
745 #endif
746 
747 	return (error);
748 }
749 
750 integrate void
751 sbjcn_schedrx(struct sbjcn_channel *ch)
752 {
753 
754 	ch->ch_rx_ready = 1;
755 
756 	/* Next callout will detect this flag. */
757 }
758 
759 void
760 sbjcn_break(struct sbjcn_channel *ch, int onoff)
761 {
762 	/* XXXKW do something? */
763 }
764 
765 void
766 sbjcn_modem(struct sbjcn_channel *ch, int onoff)
767 {
768 
769 	if (ch->ch_o_dtr == 0)
770 		return;
771 
772 	if (onoff)
773 		SET(ch->ch_oports, ch->ch_o_dtr);
774 	else
775 		CLR(ch->ch_oports, ch->ch_o_dtr);
776 
777 	if (!ch->ch_heldchange) {
778 		if (ch->ch_tx_busy) {
779 			ch->ch_heldtbc = ch->ch_tbc;
780 			ch->ch_tbc = 0;
781 			ch->ch_heldchange = 1;
782 		} else
783 			sbjcn_loadchannelregs(ch);
784 	}
785 }
786 
787 void
788 tiocm_to_sbjcn(struct sbjcn_channel *ch, int how, int ttybits)
789 {
790 	u_char bits;
791 
792 	bits = 0;
793 	if (ISSET(ttybits, TIOCM_DTR))
794 		SET(bits, ch->ch_o_dtr);
795 	if (ISSET(ttybits, TIOCM_RTS))
796 		SET(bits, ch->ch_o_rts);
797 
798 	switch (how) {
799 	case TIOCMBIC:
800 		CLR(ch->ch_oports, bits);
801 		break;
802 
803 	case TIOCMBIS:
804 		SET(ch->ch_oports, bits);
805 		break;
806 
807 	case TIOCMSET:
808 		ch->ch_oports = bits;
809 		break;
810 	}
811 
812 	if (!ch->ch_heldchange) {
813 		if (ch->ch_tx_busy) {
814 			ch->ch_heldtbc = ch->ch_tbc;
815 			ch->ch_tbc = 0;
816 			ch->ch_heldchange = 1;
817 		} else
818 			sbjcn_loadchannelregs(ch);
819 	}
820 }
821 
822 int
823 sbjcn_to_tiocm(struct sbjcn_channel *ch)
824 {
825 	u_char hwbits;
826 	int ttybits = 0;
827 
828 	hwbits = ch->ch_oports;
829 	if (ISSET(hwbits, ch->ch_o_dtr))
830 		SET(ttybits, TIOCM_DTR);
831 	if (ISSET(hwbits, ch->ch_o_rts))
832 		SET(ttybits, TIOCM_RTS);
833 
834 	hwbits = ch->ch_iports;
835 	if (ISSET(hwbits, ch->ch_i_dcd))
836 		SET(ttybits, TIOCM_CD);
837 	if (ISSET(hwbits, ch->ch_i_cts))
838 		SET(ttybits, TIOCM_CTS);
839 	if (ISSET(hwbits, ch->ch_i_dsr))
840 		SET(ttybits, TIOCM_DSR);
841 	if (ISSET(hwbits, ch->ch_i_ri))
842 		SET(ttybits, TIOCM_RI);
843 
844 	if (ch->ch_imr != 0)
845 		SET(ttybits, TIOCM_LE);
846 
847 	return (ttybits);
848 }
849 
850 static int
851 cflag2modes(tcflag_t cflag, u_char *mode1p, u_char *mode2p)
852 {
853 	u_char mode1;
854 	u_char mode2;
855 	int err = 0;
856 
857 	mode1 = mode2 = 0;
858 
859 	switch (ISSET(cflag, CSIZE)) {
860 	case CS7:
861 		mode1 |= 2;			/* XXX */
862 		break;
863 	default:
864 		err = -1;
865 		/* FALLTHRU for sanity */
866 	case CS8:
867 		mode1 |= 3;			/* XXX */
868 		break;
869 	}
870 	if (!ISSET(cflag, PARENB))
871 		mode1 |= 2 << 3;
872 	else {
873 		mode1 |= 0 << 3;
874 		if (ISSET(cflag, PARODD))
875 			mode1 |= 1 << 2;
876 	}
877 
878 	if (ISSET(cflag, CSTOPB))
879 		mode2 |= 1 << 3;		/* two stop bits XXX not std */
880 
881 	if (ISSET(cflag, CRTSCTS)) {
882 		mode1 |= 1 << 7;
883 		mode2 |= 1 << 4;
884 	}
885 
886 	*mode1p = mode1;
887 	*mode2p = mode2;
888 	return (err);
889 }
890 
891 int
892 sbjcn_param(struct tty *tp, struct termios *t)
893 {
894 	struct sbjcn_softc *sc = device_lookup_private(&sbjcn_cd, SBJCN_UNIT(tp->t_dev));
895 	struct sbjcn_channel *ch = &sc->sc_channels[SBJCN_CHAN(tp->t_dev)];
896 	long brc;
897 	u_char mode1, mode2;
898 	int s;
899 
900 /* XXX reset to console parameters if console? */
901 #if 0
902 XXX disable, enable.
903 #endif
904 
905 	/* Check requested parameters. */
906 	if (sbjcn_speed(t->c_ospeed, &brc) < 0)
907 		return (EINVAL);
908 	if (t->c_ispeed && t->c_ispeed != t->c_ospeed)
909 		return (EINVAL);
910 
911 	/*
912 	 * For the console, always force CLOCAL and !HUPCL, so that the port
913 	 * is always active.
914 	 */
915 	if (ISSET(ch->ch_swflags, TIOCFLAG_SOFTCAR) ||
916 	    ISSET(ch->ch_hwflags, SBJCN_HW_CONSOLE)) {
917 		SET(t->c_cflag, CLOCAL);
918 		CLR(t->c_cflag, HUPCL);
919 	}
920 
921 	/*
922 	 * If there were no changes, don't do anything.  This avoids dropping
923 	 * input and improves performance when all we did was frob things like
924 	 * VMIN and VTIME.
925 	 */
926 	if (tp->t_ospeed == t->c_ospeed &&
927 	    tp->t_cflag == t->c_cflag)
928 		return (0);
929 
930 	if (cflag2modes(t->c_cflag, &mode1, &mode2) < 0)
931 		return (EINVAL);
932 
933 	s = splserial();
934 
935 	ch->ch_mode1 = mode1;
936 	ch->ch_mode2 = mode2;
937 
938 	/*
939 	 * If we're not in a mode that assumes a connection is present, then
940 	 * ignore carrier changes.
941 	 */
942 	if (ISSET(t->c_cflag, CLOCAL | MDMBUF))
943 		ch->ch_i_dcd = 0;
944 	else
945 		ch->ch_i_dcd = ch->ch_i_dcd_pin;
946 	/*
947 	 * Set the flow control pins depending on the current flow control
948 	 * mode.
949 	 */
950 	if (ISSET(t->c_cflag, CRTSCTS)) {
951 		ch->ch_o_dtr = ch->ch_o_dtr_pin;
952 		ch->ch_o_rts = ch->ch_o_rts_pin;
953 		ch->ch_i_cts = ch->ch_i_cts_pin;
954 		/* hw controle enable bits in mod regs set by cflag2modes */
955 	} else if (ISSET(t->c_cflag, MDMBUF)) {
956 		/*
957 		 * For DTR/DCD flow control, make sure we don't toggle DTR for
958 		 * carrier detection.
959 		 */
960 		ch->ch_o_dtr = 0;
961 		ch->ch_o_rts = ch->ch_o_dtr_pin;
962 		ch->ch_i_cts = ch->ch_i_dcd_pin;
963 	} else {
964 		/*
965 		 * If no flow control, then always set RTS.  This will make
966 		 * the other side happy if it mistakenly thinks we're doing
967 		 * RTS/CTS flow control.
968 		 */
969 		ch->ch_o_dtr = ch->ch_o_dtr_pin | ch->ch_o_rts_pin;
970 		ch->ch_o_rts = 0;
971 		ch->ch_i_cts = 0;
972 		if (ISSET(ch->ch_oports, ch->ch_o_dtr_pin))
973 			SET(ch->ch_oports, ch->ch_o_rts_pin);
974 		else
975 			CLR(ch->ch_oports, ch->ch_o_rts_pin);
976 	}
977 	/* XXX maybe mask the ports which generate intrs? */
978 
979 	ch->ch_brc = brc;
980 
981 	/* XXX maybe set fifo-full receive mode if RTSCTS and high speed? */
982 
983 	/* And copy to tty. */
984 	tp->t_ispeed = 0;
985 	tp->t_ospeed = t->c_ospeed;
986 	tp->t_cflag = t->c_cflag;
987 
988 	if (!ch->ch_heldchange) {
989 		if (ch->ch_tx_busy) {
990 			ch->ch_heldtbc = ch->ch_tbc;
991 			ch->ch_tbc = 0;
992 			ch->ch_heldchange = 1;
993 		} else
994 			sbjcn_loadchannelregs(ch);
995 	}
996 
997 	if (!ISSET(t->c_cflag, CHWFLOW)) {
998 		/* Disable the high water mark. */
999 		ch->ch_r_hiwat = 0;
1000 		ch->ch_r_lowat = 0;
1001 		if (ISSET(ch->ch_rx_flags, RX_TTY_OVERFLOWED)) {
1002 			CLR(ch->ch_rx_flags, RX_TTY_OVERFLOWED);
1003 			sbjcn_schedrx(ch);
1004 		}
1005 		if (ISSET(ch->ch_rx_flags, RX_TTY_BLOCKED|RX_IBUF_BLOCKED)) {
1006 			CLR(ch->ch_rx_flags, RX_TTY_BLOCKED|RX_IBUF_BLOCKED);
1007 			sbjcn_dohwiflow(ch);
1008 		}
1009 	} else {
1010 		ch->ch_r_hiwat = sbjcn_rbuf_hiwat;
1011 		ch->ch_r_lowat = sbjcn_rbuf_lowat;
1012 	}
1013 
1014 	splx(s);
1015 
1016 	/*
1017 	 * Update the tty layer's idea of the carrier bit, in case we changed
1018 	 * CLOCAL or MDMBUF.  We don't hang up here; we only do that by
1019 	 * explicit request.
1020 	 */
1021 	(void) (*tp->t_linesw->l_modem)(tp,
1022 	    ISSET(ch->ch_iports, ch->ch_i_dcd));
1023 
1024 #ifdef SBJCN_DEBUG
1025 	if (sbjcn_debug)
1026 		sbjcn_status(ch, "sbjcnparam ");
1027 #endif
1028 
1029 	if (!ISSET(t->c_cflag, CHWFLOW)) {
1030 		if (ch->ch_tx_stopped) {
1031 			ch->ch_tx_stopped = 0;
1032 			sbjcn_start(tp);
1033 		}
1034 	}
1035 
1036 	return (0);
1037 }
1038 
1039 void
1040 sbjcn_iflush(struct sbjcn_channel *ch)
1041 {
1042 	uint64_t reg;
1043 	int timo;
1044 
1045 	timo = 50000;
1046 	/* flush any pending I/O */
1047 	while (((reg = READ_REG(ch->ch_input_reg)) != 0) && --timo)
1048 		;
1049 
1050 #ifdef DIAGNOSTIC
1051 	if (!timo)
1052 		aprint_error_dev(ch->ch_sc->sc_dev,
1053 		    "sbjcn_iflush timeout %02x\n", reg);
1054 #endif
1055 }
1056 
1057 void
1058 sbjcn_loadchannelregs(struct sbjcn_channel *ch)
1059 {
1060 }
1061 
1062 int
1063 sbjcn_hwiflow(struct tty *tp, int block)
1064 {
1065 	struct sbjcn_softc *sc = device_lookup_private(&sbjcn_cd, SBJCN_UNIT(tp->t_dev));
1066 	struct sbjcn_channel *ch = &sc->sc_channels[SBJCN_CHAN(tp->t_dev)];
1067 	int s;
1068 
1069 	if (ch->ch_o_rts == 0)
1070 		return (0);
1071 
1072 	s = splserial();
1073 	if (block) {
1074 		if (!ISSET(ch->ch_rx_flags, RX_TTY_BLOCKED)) {
1075 			SET(ch->ch_rx_flags, RX_TTY_BLOCKED);
1076 			sbjcn_dohwiflow(ch);
1077 		}
1078 	} else {
1079 		if (ISSET(ch->ch_rx_flags, RX_TTY_OVERFLOWED)) {
1080 			CLR(ch->ch_rx_flags, RX_TTY_OVERFLOWED);
1081 			sbjcn_schedrx(ch);
1082 		}
1083 		if (ISSET(ch->ch_rx_flags, RX_TTY_BLOCKED)) {
1084 			CLR(ch->ch_rx_flags, RX_TTY_BLOCKED);
1085 			sbjcn_dohwiflow(ch);
1086 		}
1087 	}
1088 	splx(s);
1089 	return (1);
1090 }
1091 
1092 /*
1093  * (un)block input via hw flowcontrol
1094  */
1095 void
1096 sbjcn_dohwiflow(struct sbjcn_channel *ch)
1097 {
1098 
1099 	if (ch->ch_o_rts == 0)
1100 		return;
1101 
1102 	if (ISSET(ch->ch_rx_flags, RX_ANY_BLOCK)) {
1103 		CLR(ch->ch_oports, ch->ch_o_rts);
1104 		CLR(ch->ch_oports_active, ch->ch_o_rts);
1105 	} else {
1106 		SET(ch->ch_oports, ch->ch_o_rts);
1107 		SET(ch->ch_oports_active, ch->ch_o_rts);
1108 	}
1109 }
1110 
1111 void
1112 sbjcn_start(struct tty *tp)
1113 {
1114 	struct sbjcn_softc *sc = device_lookup_private(&sbjcn_cd, SBJCN_UNIT(tp->t_dev));
1115 	struct sbjcn_channel *ch = &sc->sc_channels[SBJCN_CHAN(tp->t_dev)];
1116 	int s;
1117 
1118 	s = spltty();
1119 	if (ISSET(tp->t_state, TS_BUSY | TS_TIMEOUT | TS_TTSTOP))
1120 		goto out;
1121 	if (ch->ch_tx_stopped)
1122 		goto out;
1123 	if (!ttypull(tp))
1124 		goto out;
1125 
1126 	/* Grab the first contiguous region of buffer space. */
1127 	{
1128 		u_char *tba;
1129 		int tbc;
1130 
1131 		tba = tp->t_outq.c_cf;
1132 		tbc = ndqb(&tp->t_outq, 0);
1133 
1134 		(void)splserial();
1135 
1136 		ch->ch_tba = tba;
1137 		ch->ch_tbc = tbc;
1138 	}
1139 
1140 	SET(tp->t_state, TS_BUSY);
1141 	ch->ch_tx_busy = 1;
1142 
1143 	/* Output the first chunk of the contiguous buffer. */
1144 	{
1145 		while (ch->ch_tbc) {
1146 			uint64_t data;
1147 			int bytes, i;
1148 
1149 			bytes = (ch->ch_tbc > 7) ? 7 : ch->ch_tbc;
1150 			data = bytes;
1151 			for (i=0; i<bytes; i++) {
1152 				data <<= 8;
1153 				data |= *ch->ch_tba++;
1154 			}
1155 			if (bytes < 7)
1156 				data <<= 56-(bytes<<3);
1157 			ch->ch_tbc -= bytes;
1158 			WRITE_REG(ch->ch_output_reg, data);
1159 		}
1160 		ch->ch_tx_busy = 0;
1161 		ch->ch_tx_done = 1;
1162 	}
1163 out:
1164 	splx(s);
1165 	return;
1166 }
1167 
1168 /*
1169  * Stop output on a line.
1170  */
1171 void
1172 sbjcnstop(struct tty *tp, int flag)
1173 {
1174 	struct sbjcn_softc *sc = device_lookup_private(&sbjcn_cd, SBJCN_UNIT(tp->t_dev));
1175 	struct sbjcn_channel *ch = &sc->sc_channels[SBJCN_CHAN(tp->t_dev)];
1176 	int s;
1177 
1178 	s = splserial();
1179 	if (ISSET(tp->t_state, TS_BUSY)) {
1180 		/* Stop transmitting at the next chunk. */
1181 		ch->ch_tbc = 0;
1182 		ch->ch_heldtbc = 0;
1183 		if (!ISSET(tp->t_state, TS_TTSTOP))
1184 			SET(tp->t_state, TS_FLUSH);
1185 	}
1186 	splx(s);
1187 }
1188 
1189 void
1190 sbjcn_diag(void *arg)
1191 {
1192 	struct sbjcn_channel *ch = arg;
1193 	struct sbjcn_softc *sc = ch->ch_sc;
1194 	int overflows, floods;
1195 	int s;
1196 
1197 	s = splserial();
1198 	overflows = ch->ch_overflows;
1199 	ch->ch_overflows = 0;
1200 	floods = ch->ch_floods;
1201 	ch->ch_floods = 0;
1202 	ch->ch_errors = 0;
1203 	splx(s);
1204 
1205 	log(LOG_WARNING, "%s: channel %d: %d fifo overflow%s, %d ibuf flood%s\n",
1206 	    device_xname(sc->sc_dev), ch->ch_num,
1207 	    overflows, overflows == 1 ? "" : "s",
1208 	    floods, floods == 1 ? "" : "s");
1209 }
1210 
1211 integrate void
1212 sbjcn_rxsoft(struct sbjcn_channel *ch, struct tty *tp)
1213 {
1214 	int (*rint)(int c, struct tty *tp) = tp->t_linesw->l_rint;
1215 	u_char *get, *end;
1216 	u_int cc, scc;
1217 	u_char sr;
1218 	int code;
1219 	int s;
1220 
1221 	end = ch->ch_ebuf;
1222 	get = ch->ch_rbget;
1223 	scc = cc = sbjcn_rbuf_size - ch->ch_rbavail;
1224 
1225 	if (cc == sbjcn_rbuf_size) {
1226 		ch->ch_floods++;
1227 		if (ch->ch_errors++ == 0)
1228 			callout_reset(&ch->ch_diag_callout, 60 * hz,
1229 			    sbjcn_diag, ch);
1230 	}
1231 
1232 	while (cc) {
1233 		code = get[0];
1234 		sr = get[1];
1235 		if (ISSET(sr, 0xf0)) {
1236 			if (ISSET(sr, 0x10)) {
1237 				ch->ch_overflows++;
1238 				if (ch->ch_errors++ == 0)
1239 					callout_reset(&ch->ch_diag_callout,
1240 					    60 * hz, sbjcn_diag, ch);
1241 			}
1242 			if (ISSET(sr, 0xc0))
1243 				SET(code, TTY_FE);
1244 			if (ISSET(sr, 0x20))
1245 				SET(code, TTY_PE);
1246 		}
1247 		if ((*rint)(code, tp) == -1) {
1248 			/*
1249 			 * The line discipline's buffer is out of space.
1250 			 */
1251 			if (!ISSET(ch->ch_rx_flags, RX_TTY_BLOCKED)) {
1252 				/*
1253 				 * We're either not using flow control, or the
1254 				 * line discipline didn't tell us to block for
1255 				 * some reason.  Either way, we have no way to
1256 				 * know when there's more space available, so
1257 				 * just drop the rest of the data.
1258 				 */
1259 				get += cc << 1;
1260 				if (get >= end)
1261 					get -= sbjcn_rbuf_size << 1;
1262 				cc = 0;
1263 			} else {
1264 				/*
1265 				 * Don't schedule any more receive processing
1266 				 * until the line discipline tells us there's
1267 				 * space available (through comhwiflow()).
1268 				 * Leave the rest of the data in the input
1269 				 * buffer.
1270 				 */
1271 				SET(ch->ch_rx_flags, RX_TTY_OVERFLOWED);
1272 			}
1273 			break;
1274 		}
1275 		get += 2;
1276 		if (get >= end)
1277 			get = ch->ch_rbuf;
1278 		cc--;
1279 	}
1280 
1281 	if (cc != scc) {
1282 		ch->ch_rbget = get;
1283 		s = splserial();
1284 		cc = ch->ch_rbavail += scc - cc;
1285 		/* Buffers should be ok again, release possible block. */
1286 		if (cc >= ch->ch_r_lowat) {
1287 			if (ISSET(ch->ch_rx_flags, RX_IBUF_OVERFLOWED)) {
1288 				CLR(ch->ch_rx_flags, RX_IBUF_OVERFLOWED);
1289 				SET(ch->ch_imr, 0x02);
1290 			}
1291 			if (ISSET(ch->ch_rx_flags, RX_IBUF_BLOCKED)) {
1292 				CLR(ch->ch_rx_flags, RX_IBUF_BLOCKED);
1293 				sbjcn_dohwiflow(ch);
1294 			}
1295 		}
1296 		splx(s);
1297 	}
1298 }
1299 
1300 integrate void
1301 sbjcn_txsoft(struct sbjcn_channel *ch, struct tty *tp)
1302 {
1303 
1304 	CLR(tp->t_state, TS_BUSY);
1305 	if (ISSET(tp->t_state, TS_FLUSH))
1306 		CLR(tp->t_state, TS_FLUSH);
1307 	else
1308 		ndflush(&tp->t_outq, (int)(ch->ch_tba - tp->t_outq.c_cf));
1309 	(*tp->t_linesw->l_start)(tp);
1310 }
1311 
1312 integrate void
1313 sbjcn_stsoft(struct sbjcn_channel *ch, struct tty *tp)
1314 {
1315 	u_char iports, delta;
1316 	int s;
1317 
1318 	s = splserial();
1319 	iports = ch->ch_iports;
1320 	delta = ch->ch_iports_delta;
1321 	ch->ch_iports_delta = 0;
1322 	splx(s);
1323 
1324 	if (ISSET(delta, ch->ch_i_dcd)) {
1325 		/*
1326 		 * Inform the tty layer that carrier detect changed.
1327 		 */
1328 		(void) (*tp->t_linesw->l_modem)(tp,
1329 		    ISSET(iports, ch->ch_i_dcd));
1330 	}
1331 
1332 	if (ISSET(delta, ch->ch_i_cts)) {
1333 		/* Block or unblock output according to flow control. */
1334 		if (ISSET(iports, ch->ch_i_cts)) {
1335 			ch->ch_tx_stopped = 0;
1336 			(*tp->t_linesw->l_start)(tp);
1337 		} else {
1338 			ch->ch_tx_stopped = 1;
1339 		}
1340 	}
1341 
1342 #ifdef SBJCN_DEBUG
1343 	if (sbjcn_debug)
1344 		sbjcn_status(ch, "sbjcn_stsoft");
1345 #endif
1346 }
1347 
1348 integrate void
1349 sbjcn_recv(struct sbjcn_channel *ch)
1350 {
1351 	u_char *put, *end;
1352 	u_int cc;
1353 
1354 	end = ch->ch_ebuf;
1355 	put = ch->ch_rbput;
1356 	cc = ch->ch_rbavail;
1357 
1358 	/* XXX process break */
1359 
1360 	sbjcncn_grabdword(ch);
1361 	if (ch->ch_waiting_input) {
1362 		if (!ISSET(ch->ch_rx_flags, RX_IBUF_OVERFLOWED)) {
1363 			while (cc > 0) {
1364 				put[0] = sbjcncn_nextbyte(ch);
1365 				put[1] = 1; /* XXXKW ? */
1366 				put += 2;
1367 				if (put >= end)
1368 					put = ch->ch_rbuf;
1369 				cc--;
1370 
1371 				if (!ch->ch_waiting_input)
1372 					break;
1373 			}
1374 
1375 			/*
1376 			 * Current string of incoming characters ended
1377 			 * because no more data was available or we
1378 			 * ran out of space.  Schedule a receive event
1379 			 * if any data was received.  If we're out of
1380 			 * space, turn off receive interrupts.
1381 			 */
1382 			ch->ch_rbput = put;
1383 			ch->ch_rbavail = cc;
1384 			if (!ISSET(ch->ch_rx_flags, RX_TTY_OVERFLOWED))
1385 				ch->ch_rx_ready = 1;
1386 
1387 			/*
1388 			 * See if we are in danger of overflowing a
1389 			 * buffer. If so, use hardware flow control
1390 			 * to ease the pressure.
1391 			 */
1392 			if (!ISSET(ch->ch_rx_flags, RX_IBUF_BLOCKED) &&
1393 			    cc < ch->ch_r_hiwat) {
1394 				SET(ch->ch_rx_flags, RX_IBUF_BLOCKED);
1395 				sbjcn_dohwiflow(ch);
1396 			}
1397 
1398 			/*
1399 			 * If we're out of space, disable receive
1400 			 * interrupts until the queue has drained
1401 			 * a bit.
1402 			 */
1403 			if (!cc) {
1404 				SET(ch->ch_rx_flags,
1405 				RX_IBUF_OVERFLOWED);
1406 				CLR(ch->ch_imr, 0x02);
1407 			}
1408 		} else {
1409 			/* XXX panic? */
1410 			CLR(ch->ch_imr, 0x02);
1411 			//			continue;
1412 		}
1413 	}
1414 
1415 	/*
1416 	 * If we've delayed a parameter change, do it now, and restart
1417 	 * output.
1418 	 */
1419 	if (ch->ch_heldchange) {
1420 		sbjcn_loadchannelregs(ch);
1421 		ch->ch_heldchange = 0;
1422 		ch->ch_tbc = ch->ch_heldtbc;
1423 		ch->ch_heldtbc = 0;
1424 	}
1425 }
1426 
1427 void
1428 sbjcn_callout(void *arg)
1429 {
1430 	struct sbjcn_channel *ch = arg;
1431 	struct tty *tp = ch->ch_tty;
1432 
1433 	/* XXX get stuff */
1434 	sbjcn_recv(ch);
1435 
1436 	/* XXX check receive */
1437 	if (ch->ch_rx_ready) {
1438 		ch->ch_rx_ready = 0;
1439 		sbjcn_rxsoft(ch, tp);
1440 	}
1441 
1442 	/* XXX check transmit */
1443 	if (ch->ch_tx_done) {
1444 		ch->ch_tx_done = 0;
1445 		sbjcn_txsoft(ch, tp);
1446 	}
1447 
1448 	callout_reset(&ch->ch_callout, hz/10, sbjcn_callout, ch);
1449 }
1450 
1451 static char sbjcncn_nextbyte(struct sbjcn_channel *ch)
1452 {
1453 	char c;
1454 
1455 	sbjcncn_grabdword(ch);
1456 	c = (ch->ch_input_buf >> 56) & 0xff;
1457 	ch->ch_input_buf <<= 8;
1458 	ch->ch_waiting_input--;
1459 	return c;
1460 }
1461 
1462 static void sbjcncn_grabdword(struct sbjcn_channel *ch)
1463 {
1464 	uint64_t inbuf;
1465 
1466 	if (ch->ch_waiting_input)
1467 		return;
1468 
1469 	inbuf = READ_REG(ch->ch_input_reg);
1470 	ch->ch_waiting_input = jtag_input_len(inbuf);
1471 	ch->ch_input_buf = inbuf << 8;
1472 }
1473 
1474 /*
1475  * Initialize UART for use as console or KGDB line.
1476  */
1477 int
1478 sbjcn_init(u_long addr, int chan, int rate, tcflag_t cflag)
1479 {
1480 	/* XXXKW Anything to do here? */
1481 	return (0);
1482 }
1483 
1484 /*
1485  * Following are all routines needed for sbjcn to act as console
1486  */
1487 int
1488 sbjcn_cnattach(u_long addr, int chan, int rate, tcflag_t cflag)
1489 {
1490 	int res;
1491 	uint64_t ctrl_val;
1492 	static struct consdev sbjcn_cons = {
1493 		NULL, NULL, sbjcn_cngetc, sbjcn_cnputc, sbjcn_cnpollc, NULL,
1494 		    NODEV, CN_NORMAL
1495 	};
1496 
1497 	res = sbjcn_init(addr, chan, rate, cflag);
1498 	if (res)
1499 		return (res);
1500 
1501 	cn_tab = &sbjcn_cons;
1502 
1503 	sbjcn_cons_present = 1;
1504 	sbjcn_cons_addr = addr;
1505 	sbjcn_cons_waiting_input = 0;
1506 	sbjcn_cons_chan = chan;
1507 	sbjcn_cons_rate = rate;
1508 	sbjcn_cons_cflag = cflag;
1509 
1510 	/* Wait for sign of life from the other end */
1511 	while ((ctrl_val = READ_REG(MIPS_PHYS_TO_KSEG1(sbjcn_cons_addr + JTAG_CONS_CONTROL))) == 0)
1512 		;
1513 
1514 	return (ctrl_val != JTAG_CONS_MAGICNUM);
1515 }
1516 
1517 int
1518 sbjcn_cngetc(dev_t dev)
1519 {
1520 	char c;
1521 
1522 	while (sbjcn_cons_waiting_input == 0)
1523 		sbjcn_cngrabdword();
1524 
1525 	c = (sbjcn_cons_input_buf >> 56) & 0xff;
1526 	sbjcn_cons_input_buf <<= 8;
1527 	sbjcn_cons_waiting_input--;
1528 
1529 	return c;
1530 }
1531 
1532 /*
1533  * Console kernel output character routine.
1534  */
1535 void
1536 sbjcn_cnputc(dev_t dev, int c)
1537 {
1538 	uint64_t outbuf;
1539 
1540 	outbuf = (1LL << 56) | (((uint64_t)c) << 48);
1541 	WRITE_REG(MIPS_PHYS_TO_KSEG1(sbjcn_cons_addr + JTAG_CONS_OUTPUT), outbuf);
1542 }
1543 
1544 void
1545 sbjcn_cnpollc(dev_t dev, int on)
1546 {
1547 
1548 }
1549 
1550 static void sbjcn_cngrabdword(void)
1551 {
1552 	uint64_t inbuf;
1553 
1554 	if (sbjcn_cons_waiting_input)
1555 		return;
1556 
1557 	inbuf = READ_REG(MIPS_PHYS_TO_KSEG1(sbjcn_cons_addr + JTAG_CONS_INPUT));
1558 	sbjcn_cons_waiting_input = jtag_input_len(inbuf);
1559 	sbjcn_cons_input_buf = inbuf << 8;
1560 }
1561 
1562 #ifdef KGDB
1563 int
1564 sbjcn_kgdb_attach(u_long addr, int chan, int rate, tcflag_t cflag)
1565 {
1566 	int res;
1567 
1568 	if (!sbjcn_cons_present &&
1569 	    sbjcn_cons_addr == addr && sbjcn_cons_chan == chan)
1570 		return (EBUSY); /* cannot share with console */
1571 
1572 	res = sbjcn_init(addr, chan, rate, cflag);
1573 	if (res)
1574 		return (res);
1575 
1576 	kgdb_attach(sbjcn_kgdb_getc, sbjcn_kgdb_putc, NULL);
1577 	kgdb_dev = 123; /* unneeded, only to satisfy some tests */
1578 	kgdb_rate = rate;
1579 
1580 	sbjcn_kgdb_present = 1;
1581 	/* XXX sbjcn_init wants addr, but we need the offset addr */
1582 	sbjcn_kgdb_addr = addr + (chan * 0x100);
1583 	sbjcn_kgdb_chan = chan;
1584 
1585 	return (0);
1586 }
1587 
1588 /* ARGSUSED */
1589 int
1590 sbjcn_kgdb_getc(void *arg)
1591 {
1592 
1593 	return (sbjcn_common_getc(sbjcn_kgdb_addr, sbjcn_kgdb_chan));
1594 }
1595 
1596 /* ARGSUSED */
1597 void
1598 sbjcn_kgdb_putc(void *arg, int c)
1599 {
1600 
1601 	sbjcn_common_putc(sbjcn_kgdb_addr, sbjcn_kgdb_chan, c);
1602 }
1603 #endif /* KGDB */
1604 
1605 /*
1606  * helper function to identify the sbjcn channels used by
1607  * console or KGDB (and not yet autoconf attached)
1608  */
1609 int
1610 sbjcn_is_console(u_long addr, int chan)
1611 {
1612 
1613 	if (sbjcn_cons_present && !sbjcn_cons_attached &&
1614 	    sbjcn_cons_addr == addr && sbjcn_cons_chan == chan)
1615 		return (1);
1616 #ifdef KGDB
1617 	if (sbjcn_kgdb_present && !sbjcn_kgdb_attached &&
1618 	    sbjcn_kgdb_addr == addr && sbjcn_kgdb_chan == chan)
1619 		return (1);
1620 #endif
1621 	return (0);
1622 }
1623