xref: /netbsd-src/sys/arch/emips/ebus/dz_ebus.c (revision 6a493d6bc668897c91594964a732d38505b70cbb)
1 /*	$NetBSD: dz_ebus.c,v 1.6 2013/11/10 18:27:15 christos Exp $	*/
2 
3 /*-
4  * Copyright (c) 2010 The NetBSD Foundation, Inc.
5  * All rights reserved.
6  *
7  * This code was written by Alessandro Forin and Neil Pittman
8  * at Microsoft Research and contributed to The NetBSD Foundation
9  * by Microsoft Corporation.
10  *
11  * Redistribution and use in source and binary forms, with or without
12  * modification, are permitted provided that the following conditions
13  * are met:
14  * 1. Redistributions of source code must retain the above copyright
15  *    notice, this list of conditions and the following disclaimer.
16  * 2. Redistributions in binary form must reproduce the above copyright
17  *    notice, this list of conditions and the following disclaimer in the
18  *    documentation and/or other materials provided with the distribution.
19  *
20  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
21  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
22  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
23  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
24  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
25  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
26  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
27  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
28  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
29  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
30  * POSSIBILITY OF SUCH DAMAGE.
31  */
32 
33 #include <sys/cdefs.h>
34 __KERNEL_RCSID(0, "$NetBSD: dz_ebus.c,v 1.6 2013/11/10 18:27:15 christos Exp $");
35 
36 #include "opt_ddb.h"
37 
38 #include <sys/param.h>
39 #include <sys/systm.h>
40 #include <sys/callout.h>
41 #include <sys/ioctl.h>
42 #include <sys/tty.h>
43 #include <sys/proc.h>
44 #include <sys/buf.h>
45 #include <sys/conf.h>
46 #include <sys/file.h>
47 #include <sys/uio.h>
48 #include <sys/kernel.h>
49 #include <sys/syslog.h>
50 #include <sys/device.h>
51 #include <sys/kauth.h>
52 
53 #include <machine/bus.h>
54 #include <machine/emipsreg.h>
55 
56 #include <dev/cons.h>
57 
58 
59 #include <emips/ebus/ebusvar.h>
60 #include <emips/emips/cons.h>
61 #if 0
62 #include <emips/emips/machdep.h>
63 #endif
64 
65 #include "ioconf.h" /* for dz_cd */
66 
67 #define DZ_C2I(c)	((c) << 3)	/* convert controller # to index */
68 #define DZ_I2C(c)	((c) >> 3)	/* convert minor to controller # */
69 #define DZ_PORT(u)	((u) & 07)	/* extract the port # */
70 
71 struct	dz_softc {
72 	device_t	sc_dev;		/* Autoconf blaha */
73 	struct	evcnt	sc_rintrcnt;	/* recevive interrupt counts */
74 	struct	evcnt	sc_tintrcnt;	/* transmit interrupt counts */
75 	struct	_Usart	*sc_dr;		/* reg pointers */
76 	bus_space_tag_t	sc_iot;
77 	bus_space_handle_t sc_ioh;
78 	int		sc_consline;	/* console line, or -1 */
79 	int		sc_rxint;	/* Receive interrupt count XXX */
80 	u_char		sc_brk;		/* Break asserted on some lines */
81 	u_char		sc_dsr;		/* DSR set bits if no mdm ctrl */
82 	struct dz_linestate {
83 		struct	dz_softc *dz_sc;	/* backpointer to softc */
84 		int		dz_line;	/* channel number */
85 		struct	tty	*dz_tty;	/* what we work on */
86 	} sc_dz;
87 };
88 
89 void	dzrint(struct dz_softc *, uint32_t);
90 void	dzxint(struct dz_softc *, uint32_t);
91 
92 #ifndef TIOCM_BRK
93 #define TIOCM_BRK		0100000		/* no equivalent */
94 
95 static void	dzstart(struct tty *);
96 static int	dzparam(struct tty *, struct termios *);
97 static unsigned dzmctl(struct dz_softc *sc, int line,
98                        int bits, /* one of the TIOCM_xx */
99                        int how); /* one of the DMSET/BIS.. */
100 
101 #include <dev/dec/dzkbdvar.h>
102 #endif
103 
104 dev_type_open(dzopen);
105 dev_type_close(dzclose);
106 dev_type_read(dzread);
107 dev_type_write(dzwrite);
108 dev_type_ioctl(dzioctl);
109 dev_type_stop(dzstop);
110 dev_type_tty(dztty);
111 dev_type_poll(dzpoll);
112 
113 const struct cdevsw dz_cdevsw = {
114 	dzopen, dzclose, dzread, dzwrite, dzioctl,
115 	dzstop, dztty, dzpoll, nommap, ttykqfilter, D_TTY
116 };
117 
118 int
119 dzopen(dev_t dev, int flag, int mode, struct lwp *l)
120 {
121 	struct tty *tp;
122 	int unit, line;
123 	struct dz_softc *sc;
124 	int s, error = 0;
125 
126 	unit = DZ_I2C(minor(dev));
127 	sc = device_lookup_private(&dz_cd, unit);
128 	if (sc == NULL)
129 		return ENXIO;
130 
131 	line = DZ_PORT(minor(dev));
132 	if (line > 0) /* FIXME for more than one line */
133 		return ENXIO;
134 
135 	tp = sc->sc_dz.dz_tty;
136 	if (tp == NULL)
137 		return ENODEV;
138 	tp->t_oproc = dzstart;
139 	tp->t_param = dzparam;
140 	tp->t_dev   = dev;
141 
142 	if (kauth_authorize_device_tty(l->l_cred, KAUTH_DEVICE_TTY_OPEN, tp))
143 		return (EBUSY);
144 
145 	if ((tp->t_state & TS_ISOPEN) == 0) {
146 		ttychars(tp);
147 		if (tp->t_ispeed == 0) {
148 			tp->t_iflag = TTYDEF_IFLAG;
149 			tp->t_oflag = TTYDEF_OFLAG;
150 			tp->t_cflag = TTYDEF_CFLAG;
151 			tp->t_lflag = TTYDEF_LFLAG;
152 			tp->t_ispeed = tp->t_ospeed = TTYDEF_SPEED;
153 		}
154 		(void)dzparam(tp, &tp->t_termios);
155 		ttsetwater(tp);
156 	}
157 	/* we have no modem control but..*/
158 	if (dzmctl(sc, line, TIOCM_DTR, DMBIS) & TIOCM_CD)
159 		tp->t_state |= TS_CARR_ON;
160 		s = spltty();
161 		while (!(flag & O_NONBLOCK) && !(tp->t_cflag & CLOCAL) &&
162 		    !(tp->t_state & TS_CARR_ON)) {
163 			tp->t_wopen++;
164 			error = ttysleep(tp, &tp->t_rawcv, true, 0);
165 			tp->t_wopen--;
166 			if (error)
167 				break;
168 		}
169 	(void)splx(s);
170 	if (error)
171 		return error;
172 	return (*tp->t_linesw->l_open)(dev, tp);
173 }
174 
175 int
176 dzclose(dev_t dev, int flag, int mode, struct lwp *l)
177 {
178 	struct dz_softc *sc;
179 	struct tty *tp;
180 	int unit, line;
181 
182 	unit = DZ_I2C(minor(dev));
183 	sc = device_lookup_private(&dz_cd, unit);
184 	line = DZ_PORT(minor(dev));
185 
186 	tp = sc->sc_dz.dz_tty;
187 
188 	(*tp->t_linesw->l_close)(tp, flag);
189 
190 	/* Make sure a BREAK state is not left enabled. */
191 	(void)dzmctl(sc, line, TIOCM_BRK, DMBIC);
192 
193 	/* Do a hangup if so required. */
194 	if ((tp->t_cflag & HUPCL) || tp->t_wopen || !(tp->t_state & TS_ISOPEN))
195 		(void)dzmctl(sc, line, 0, DMSET);
196 
197 	return ttyclose(tp);
198 }
199 
200 int
201 dzread(dev_t dev, struct uio *uio, int flag)
202 {
203 	struct tty *tp;
204 	struct dz_softc *sc;
205 
206 	sc = device_lookup_private(&dz_cd, DZ_I2C(minor(dev)));
207 
208 	tp = sc->sc_dz.dz_tty;
209 	return (*tp->t_linesw->l_read)(tp, uio, flag);
210 }
211 
212 int
213 dzwrite(dev_t dev, struct uio *uio, int flag)
214 {
215 	struct tty *tp;
216 	struct dz_softc *sc;
217 
218 	sc = device_lookup_private(&dz_cd, DZ_I2C(minor(dev)));
219 
220 	tp = sc->sc_dz.dz_tty;
221 	return (*tp->t_linesw->l_write)(tp, uio, flag);
222 }
223 
224 /*ARGSUSED*/
225 int
226 dzioctl(dev_t dev, u_long cmd, void *data, int flag, struct lwp *l)
227 {
228 	struct	dz_softc *sc;
229 	struct tty *tp;
230 	int unit, line;
231 	int error;
232 
233 	unit = DZ_I2C(minor(dev));
234 	line = 0;
235 	sc = device_lookup_private(&dz_cd, unit);
236 	tp = sc->sc_dz.dz_tty;
237 
238 	error = (*tp->t_linesw->l_ioctl)(tp, cmd, data, flag, l);
239 	if (error >= 0)
240 		return error;
241 
242 	error = ttioctl(tp, cmd, data, flag, l);
243 	if (error >= 0)
244 		return error;
245 
246 	switch (cmd) {
247 
248 	case TIOCSBRK:
249 		(void)dzmctl(sc, line, TIOCM_BRK, DMBIS);
250 		break;
251 
252 	case TIOCCBRK:
253 		(void)dzmctl(sc, line, TIOCM_BRK, DMBIC);
254 		break;
255 
256 	case TIOCSDTR:
257 		(void)dzmctl(sc, line, TIOCM_DTR, DMBIS);
258 		break;
259 
260 	case TIOCCDTR:
261 		(void)dzmctl(sc, line, TIOCM_DTR, DMBIC);
262 		break;
263 
264 	case TIOCMSET:
265 		(void)dzmctl(sc, line, *(int *)data, DMSET);
266 		break;
267 
268 	case TIOCMBIS:
269 		(void)dzmctl(sc, line, *(int *)data, DMBIS);
270 		break;
271 
272 	case TIOCMBIC:
273 		(void)dzmctl(sc, line, *(int *)data, DMBIC);
274 		break;
275 
276 	case TIOCMGET:
277 		*(int *)data = dzmctl(sc, line, 0, DMGET) & ~TIOCM_BRK;
278 		break;
279 
280 	default:
281 		return EPASSTHROUGH;
282 	}
283 	return 0;
284 }
285 
286 /*ARGSUSED*/
287 void
288 dzstop(struct tty *tp, int flag)
289 {
290 
291 	if (tp->t_state & TS_BUSY)
292 		if (!(tp->t_state & TS_TTSTOP))
293 			tp->t_state |= TS_FLUSH;
294 }
295 
296 struct tty *
297 dztty(dev_t dev)
298 {
299 	struct dz_softc *sc;
300 	struct tty *tp;
301 
302 	sc = device_lookup_private(&dz_cd, DZ_I2C(minor(dev)));
303 	tp = sc->sc_dz.dz_tty;
304 
305 	return tp;
306 }
307 
308 int
309 dzpoll(dev_t dev, int events, struct lwp *l)
310 {
311 	struct dz_softc *sc;
312 	struct tty *tp;
313 
314 	sc = device_lookup_private(&dz_cd, DZ_I2C(minor(dev)));
315 
316 	tp = sc->sc_dz.dz_tty;
317 	return (*tp->t_linesw->l_poll)(tp, events, l);
318 }
319 
320 void
321 dzstart(struct tty *tp)
322 {
323 	struct dz_softc *sc;
324 	struct clist *cl;
325 	int unit, s;
326 
327 	unit = DZ_I2C(minor(tp->t_dev));
328 	sc = device_lookup_private(&dz_cd, unit);
329 
330 	s = spltty();
331 	if (tp->t_state & (TS_TIMEOUT|TS_BUSY|TS_TTSTOP)) {
332 		splx(s);
333 		return;
334 	}
335 	cl = &tp->t_outq;
336 	ttypull(tp);
337 	if (cl->c_cc == 0) {
338 		splx(s);
339 		return;
340 	}
341 
342 	tp->t_state |= TS_BUSY;
343 
344 	/* was idle, get it started */
345 	dzxint(sc,USI_TXRDY);
346 	splx(s);
347 }
348 
349 static int rclk = 25000000; /* BUGBUGBUGBUG */
350 
351 static int
352 dzdivisor(int baudrate)
353 {
354 	int act_baud, divisor, error;
355 
356 	if (baudrate <= 0)
357 		return 0;
358 
359 	divisor = (rclk / 8) / (baudrate);
360 	divisor = (divisor / 2) + (divisor & 1);
361 
362 	if (divisor <= 0)
363 		return -1;
364 	act_baud = rclk / (divisor * 16);
365 
366 	/* 10 times error in percent: */
367 	error = ((act_baud - baudrate) * 2000 / baudrate + 1) >> 1;
368 
369 	/* 3.0% maximum error tolerance: */
370 	if (error < -30 || error > 30)
371 		return -1;
372 
373 	return divisor;
374 }
375 
376 static int
377 dzparam(struct tty *tp, struct termios *t)
378 {
379 	struct	dz_softc *sc;
380 	int cflag = t->c_cflag;
381 	int unit, line;
382 	int speed;
383 	unsigned lpr;
384 	int s;
385 	struct _Usart *dzr;
386 
387 	unit = DZ_I2C(minor(tp->t_dev));
388 	line = DZ_PORT(minor(tp->t_dev));
389 	sc = device_lookup_private(&dz_cd, unit);
390 
391 	/* check requested parameters */
392 	if (t->c_ispeed != t->c_ospeed)
393 		return EINVAL;
394 	speed = dzdivisor(t->c_ispeed);
395 	if (speed < 0)
396 		return EINVAL;
397 
398 	tp->t_ispeed = t->c_ispeed;
399 	tp->t_ospeed = t->c_ospeed;
400 	tp->t_cflag = cflag;
401 
402 	{
403 		/* XXX */
404 		static int didit = 0;
405 		if (!didit && t->c_ispeed != 38400)
406 			printf("dzparam: c_ispeed %d ignored, keeping 38400\n",
407 			    t->c_ispeed);
408 		didit = 1;
409 	}
410 	speed = dzdivisor(38400);
411 
412 	if (speed == 0) {
413 		(void)dzmctl(sc, line, 0, DMSET);	/* hang up line */
414 		return 0;
415 	}
416 
417 	switch (cflag & CSIZE) {
418 	case CS5:
419 		lpr = USC_BPC_5;
420 		break;
421 	case CS6:
422 		lpr = USC_BPC_6;
423 		break;
424 	case CS7:
425 		lpr = USC_BPC_7;
426 		break;
427 	default:
428 		lpr = USC_BPC_8;
429 		break;
430 	}
431 	if (cflag & CSTOPB)
432 		lpr |= USC_2STOP;
433 
434 	if (cflag & PARENB) {
435 		if (cflag & PARODD)
436 			lpr |= USC_ODD;
437 		else
438 			lpr |= USC_EVEN;
439 	} else
440 		lpr |= USC_NONE;
441 
442 	s = spltty();
443 
444 	dzr = sc->sc_dr;
445 
446 	dzr->Baud = speed;
447 	dzr->Control = USC_CLKDIV_4 | USC_TXEN | USC_RXEN | lpr;
448 #define USI_INTRS (USI_RXRDY|USI_RXBRK|USI_OVRE|USI_FRAME|USI_PARE)
449 	dzr->IntrEnable = USI_INTRS;
450 
451 	(void)splx(s);
452 	return 0;
453 }
454 
455 static unsigned
456 dzmctl(struct dz_softc *sc, int line, int bits, int how)
457 {
458 	unsigned int mbits;
459 	int s;
460 	struct _Usart *dzr;
461 
462 	mbits = 0;
463 
464 	s = spltty();
465 
466 	dzr = sc->sc_dr;
467 
468 	/* we have no modem control bits (CD,RI,DTR,DSR,..) */
469 	mbits |= TIOCM_CD;
470 	mbits |= TIOCM_DTR;
471 
472 	if (dzr->ChannelStatus & USI_RXBRK)
473 		mbits |= TIOCM_BRK;
474 
475 	switch (how) {
476 	case DMSET:
477 		mbits = bits;
478 		break;
479 
480 	case DMBIS:
481 		mbits |= bits;
482 		break;
483 
484 	case DMBIC:
485 		mbits &= ~bits;
486 		break;
487 
488 	case DMGET:
489 		(void)splx(s);
490 		return mbits;
491 	}
492 
493 	/* BUGBUG work in progress */
494 	if (mbits & TIOCM_BRK) {
495 		sc->sc_brk |= (1 << line);
496 		dzr->Control |= USC_STTBRK;
497 	} else {
498 		sc->sc_brk &= ~(1 << line);
499 		dzr->Control |= USC_STPBRK;
500 	}
501 
502 	(void)splx(s);
503 	return mbits;
504 }
505 
506 
507 #if defined(DDB)
508 int dz_ddb = 0;
509 #endif
510 
511 /* Receiver Interrupt */
512 
513 void
514 dzrint(struct dz_softc *sc, uint32_t csr)
515 {
516 	struct tty *tp;
517 	int cc;
518 	struct _Usart *dzr;
519 
520 	sc->sc_rxint++;
521 	dzr = sc->sc_dr;
522 
523 	cc = dzr->RxData;
524 	tp = sc->sc_dz.dz_tty;
525 
526 	/* clear errors before we print or bail out */
527 	if (csr & (USI_OVRE|USI_FRAME|USI_PARE))
528 		dzr->Control = USC_RSTSTA;
529 
530 	if (!(tp->t_state & TS_ISOPEN)) {
531 		wakeup(&tp->t_rawq);
532 		return;
533 	}
534 
535 	if (csr & USI_OVRE) {
536 		log(LOG_WARNING, "%s: silo overflow, line %d\n",
537 		    device_xname(sc->sc_dev), 0);
538 	}
539 
540 	if (csr & USI_FRAME)
541 		cc |= TTY_FE;
542 	if (csr & USI_PARE)
543 		cc |= TTY_PE;
544 
545 #if defined(DDB)
546 	/* ^P drops into DDB */
547 	if (dz_ddb && (cc == 0x10))
548 		Debugger();
549 #endif
550 	(*tp->t_linesw->l_rint)(cc, tp);
551 }
552 
553 /* Transmitter Interrupt */
554 
555 void
556 dzxint(struct dz_softc *sc, uint32_t csr)
557 {
558 	struct tty *tp;
559 	struct clist *cl;
560 	int ch;
561 	struct _Usart *dzr;
562 
563 	dzr = sc->sc_dr;
564 
565 	tp = sc->sc_dz.dz_tty;
566 	cl = &tp->t_outq;
567 	tp->t_state &= ~TS_BUSY;
568 
569 	/* Just send out a char if we have one */
570 	if (cl->c_cc) {
571 		tp->t_state |= TS_BUSY;
572 		ch = getc(cl);
573 		dzr->TxData = ch;
574 		dzr->IntrEnable = USI_TXRDY;
575 		return;
576 	}
577 
578 	/* Nothing to send; turn off intr */
579 	dzr->IntrDisable = USI_TXRDY;
580 
581 	if (tp->t_state & TS_FLUSH)
582 		tp->t_state &= ~TS_FLUSH;
583 	else
584 		ndflush(&tp->t_outq, cl->c_cc);
585 
586 	(*tp->t_linesw->l_start)(tp);
587 }
588 
589 /*
590  * Machdep part of the driver
591  */
592 int	dz_ebus_match(device_t, cfdata_t, void *);
593 void	dz_ebus_attach(device_t, device_t, void *);
594 int	dz_ebus_intr(void *, void *);
595 
596 void	dz_ebus_cnsetup(paddr_t);
597 void	dz_ebus_cninit(struct consdev *);
598 int	dz_ebus_cngetc(dev_t);
599 void	dz_ebus_cnputc(dev_t, int);
600 void	dz_ebus_cnpollc(dev_t, int);
601 
602 static int	dz_ebus_getmajor(void);
603 
604 CFATTACH_DECL_NEW(dz_ebus, sizeof(struct dz_softc),
605     dz_ebus_match, dz_ebus_attach, NULL, NULL);
606 
607 struct consdev dz_ebus_consdev = {
608 	NULL, dz_ebus_cninit, dz_ebus_cngetc, dz_ebus_cnputc,
609 	dz_ebus_cnpollc, NULL, NULL, NULL, NODEV, CN_NORMAL,
610 };
611 
612 /*
613  * Points to the console regs. Special mapping until VM is turned on.
614  */
615 struct _Usart *dzcn;
616 
617 int
618 dz_ebus_match(device_t parent, cfdata_t cf, void *aux)
619 {
620 	struct ebus_attach_args *iba;
621 	struct _Usart *us;
622 
623 	iba = aux;
624 
625 	if (strcmp(iba->ia_name, "dz") != 0)
626 		return 0;
627 
628 	us = (struct _Usart *)iba->ia_vaddr;
629 	if ((us == NULL) ||
630 	    (us->Tag != PMTTAG_USART))
631 		return 0;
632 
633 	return 1;
634 }
635 
636 void
637 dz_ebus_attach(device_t parent, device_t self, void *aux)
638 {
639 	struct ebus_attach_args *iba;
640 	struct dz_softc *sc;
641 
642 	sc = device_private(self);
643 	iba = aux;
644 
645 	sc->sc_dev = self;
646 	sc->sc_dr = (struct _Usart *)iba->ia_vaddr;
647 #if DEBUG
648 	printf(" virt=%p ", (void *)sc->sc_dr);
649 #endif
650 
651 	printf(": neilsart 1 line");
652 	ebus_intr_establish(parent, (void *)iba->ia_cookie, IPL_TTY,
653 	    dz_ebus_intr, sc);
654 
655 	sc->sc_rxint = sc->sc_brk = 0;
656 	sc->sc_consline = 0;
657 
658 	/* Initialize our softc structure. Should be done in open? */
659 
660 	sc->sc_dz.dz_sc = sc;
661 	sc->sc_dz.dz_line = 0;
662 	sc->sc_dz.dz_tty = tty_alloc();
663 
664 	evcnt_attach_dynamic(&sc->sc_rintrcnt, EVCNT_TYPE_INTR, NULL,
665 	    device_xname(self), "rintr");
666 	evcnt_attach_dynamic(&sc->sc_tintrcnt, EVCNT_TYPE_INTR, NULL,
667 	    device_xname(self), "tintr");
668 
669 	/* Initialize hw regs */
670 #if 0
671 	DZ_WRITE_WORD(dr_csr, DZ_CSR_MSE | DZ_CSR_RXIE | DZ_CSR_TXIE);
672 	DZ_WRITE_BYTE(dr_dtr, 0);
673 	DZ_WRITE_BYTE(dr_break, 0);
674 #endif
675 
676 	/* Switch the console to virtual mode */
677 	dzcn = sc->sc_dr;
678 	/* And test it */
679 	printf("\n");
680 }
681 
682 static int
683 dz_ebus_getmajor(void)
684 {
685 	extern const struct cdevsw dz_cdevsw;
686 	static int cache = -1;
687 
688 	if (cache != -1)
689 		return cache;
690 
691 	return cache = cdevsw_lookup_major(&dz_cdevsw);
692 }
693 
694 int
695 dz_ebus_intr(void *cookie, void *f)
696 {
697 	struct dz_softc *sc;
698 	struct _Usart *dzr;
699 	uint32_t csr;
700 
701 	sc = cookie;
702 	dzr = sc->sc_dr;
703 
704 #define USI_INTERRUPTS (USI_INTRS|USI_TXRDY)
705 
706 	for (; ((csr = (dzr->ChannelStatus & dzr->IntrMask)) &
707 	    USI_INTERRUPTS) != 0;) {
708 		if ((csr & USI_INTRS) != 0)
709 			dzrint(sc, csr);
710 		if ((csr & USI_TXRDY) != 0)
711 			dzxint(sc, csr);
712 	}
713 
714 	return 0;
715 }
716 
717 void
718 dz_ebus_cnsetup(paddr_t addr)
719 {
720 
721 	dzcn = (struct _Usart *)addr;
722 
723 #if 0
724 	/*
725 	 * Initialize enough to xmit/recv via polling.
726 	 * Bootloader might or might not have done it.
727 	 */
728 	dzcn->Control =
729 	    USC_RXEN |
730 	    USC_TXEN |
731 	    USC_BPC_8 |
732 	    USC_NONE |
733 	    USC_1STOP |
734 	    USC_CLKDIV_4;
735 	dzcn->Baud = 0x29; /* 38400 */
736 #endif
737 
738 	/*
739 	 * Point the console at us
740 	 */
741 	cn_tab = &dz_ebus_consdev;
742 	cn_tab->cn_pri = CN_NORMAL;/*CN_REMOTE?*/
743 	cn_tab->cn_dev = makedev(dz_ebus_getmajor(), 0);
744 }
745 
746 void
747 dz_ebus_cninit(struct consdev *cn)
748 {
749 }
750 
751 int
752 dz_ebus_cngetc(dev_t dev)
753 {
754 	int c, s;
755 
756 	c = 0;
757 	s = spltty();
758 
759 	while ((dzcn->ChannelStatus & USI_RXRDY) == 0)
760 		DELAY(10);
761 	c = dzcn->RxData;
762 
763 	splx(s);
764 	if (c == 13) /* map cr->ln */
765 		c = 10;
766 	return c;
767 }
768 
769 int dzflipped = 0;
770 void
771 dz_ebus_cnputc(dev_t dev, int ch)
772 {
773 	int timeout, s;
774 
775 	/* Don't hang the machine! */
776 	timeout = 1 << 15;
777 
778 	s = spltty();
779 
780 #if 1
781 	/* Keep wired to hunt for a bug */
782 	if (dzcn && (dzcn != (struct _Usart *)0xfff90000)) {
783 		dzcn = (struct _Usart *)0xfff90000;
784 		dzflipped++;
785 	}
786 #endif
787 
788 	/* Wait until ready */
789 	while ((dzcn->ChannelStatus & USI_TXRDY) == 0)
790 		if (--timeout < 0)
791 			break;
792 
793 	/* Put the character */
794 	dzcn->TxData = ch;
795 
796 	splx(s);
797 }
798 
799 /*
800  * Called before/after going into poll mode
801  */
802 void
803 dz_ebus_cnpollc(dev_t dev, int on)
804 {
805 }
806