xref: /netbsd-src/sys/arch/sun3/dev/zs.c (revision ae1bfcddc410612bc8c58b807e1830becb69a24c)
1 /*
2  * Copyright (c) 1992, 1993
3  *	The Regents of the University of California.  All rights reserved.
4  *
5  * This software was developed by the Computer Systems Engineering group
6  * at Lawrence Berkeley Laboratory under DARPA contract BG 91-66 and
7  * contributed to Berkeley.
8  *
9  * All advertising materials mentioning features or use of this software
10  * must display the following acknowledgement:
11  *	This product includes software developed by the University of
12  *	California, Lawrence Berkeley Laboratory.
13  *
14  * Redistribution and use in source and binary forms, with or without
15  * modification, are permitted provided that the following conditions
16  * are met:
17  * 1. Redistributions of source code must retain the above copyright
18  *    notice, this list of conditions and the following disclaimer.
19  * 2. Redistributions in binary form must reproduce the above copyright
20  *    notice, this list of conditions and the following disclaimer in the
21  *    documentation and/or other materials provided with the distribution.
22  * 3. All advertising materials mentioning features or use of this software
23  *    must display the following acknowledgement:
24  *	This product includes software developed by the University of
25  *	California, Berkeley and its contributors.
26  * 4. Neither the name of the University nor the names of its contributors
27  *    may be used to endorse or promote products derived from this software
28  *    without specific prior written permission.
29  *
30  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
31  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
32  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
33  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
34  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
35  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
36  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
37  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
38  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
39  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
40  * SUCH DAMAGE.
41  *
42  *	@(#)zs.c	8.1 (Berkeley) 7/19/93
43  *
44  * from: Header: zs.c,v 1.30 93/07/19 23:44:42 torek Exp
45  * from: sparc/dev/zs.c,v 1.3 1993/10/13 02:36:44 deraadt Exp
46  * $Id: zs.c,v 1.6 1994/05/20 05:19:31 gwr Exp $
47  */
48 
49 /*
50  * Zilog Z8530 (ZSCC) driver.
51  *
52  * Runs two tty ports (ttya and ttyb) on zs0,
53  * and runs a keyboard and mouse on zs1.
54  *
55  * This driver knows far too much about chip to usage mappings.
56  */
57 #define	NZS	2		/* XXX */
58 
59 #include <sys/param.h>
60 #include <sys/systm.h>
61 #include <sys/proc.h>
62 #include <sys/device.h>
63 #include <sys/conf.h>
64 #include <sys/file.h>
65 #include <sys/ioctl.h>
66 #include <sys/tty.h>
67 #include <sys/time.h>
68 #include <sys/kernel.h>
69 #include <sys/syslog.h>
70 
71 #include <machine/autoconf.h>
72 #include <machine/cpu.h>
73 #include <machine/obio.h>
74 #include <machine/mon.h>
75 #include <machine/eeprom.h>
76 
77 #include <dev/cons.h>
78 
79 #include "kbd.h"
80 #include "zsreg.h"
81 #include "zsvar.h"
82 
83 #ifdef KGDB
84 #include <machine/remote-sl.h>
85 #endif
86 
87 #define	ZSMAJOR	12		/* XXX */
88 
89 #define	ZS_KBD		2	/* XXX */
90 #define	ZS_MOUSE	3	/* XXX */
91 
92 /* The Sun3 provides a 4.9152 MHz clock to the ZS chips. */
93 #define PCLK	(9600 * 512)	/* PCLK pin input clock rate */
94 
95 /*
96  * Select software interrupt levels.
97  */
98 #define ZSSOFT_PRI	2	/* XXX - Want TTY_PRI */
99 #define ZSHARD_PRI	6	/* Wired on the CPU board... */
100 
101 /*
102  * Software state per found chip.  This would be called `zs_softc',
103  * but the previous driver had a rather different zs_softc....
104  */
105 struct zsinfo {
106 	struct	device zi_dev;		/* base device */
107 	volatile struct zsdevice *zi_zs;/* chip registers */
108 	struct	zs_chanstate zi_cs[2];	/* channel A and B software state */
109 };
110 
111 struct tty *zs_tty[NZS * 2];		/* XXX should be dynamic */
112 
113 /* Definition of the driver for autoconfig. */
114 static int	zsmatch(struct device *, struct cfdata *, void *);
115 static void	zsattach(struct device *, struct device *, void *);
116 struct cfdriver zscd =
117     { NULL, "zs", zsmatch, zsattach, DV_TTY, sizeof(struct zsinfo) };
118 
119 /* Interrupt handlers. */
120 static int	zshard(int);
121 static int	zssoft(int);
122 
123 struct zs_chanstate *zslist;
124 
125 /* Routines called from other code. */
126 int zsopen(dev_t, int, int, struct proc *);
127 int zsclose(dev_t, int, int, struct proc *);
128 static void	zsiopen(struct tty *);
129 static void	zsiclose(struct tty *);
130 static void	zsstart(struct tty *);
131 void		zsstop(struct tty *, int);
132 static int	zsparam(struct tty *, struct termios *);
133 
134 /* Routines purely local to this driver. */
135 static int	zs_getspeed(volatile struct zschan *);
136 static void	zs_reset(volatile struct zschan *, int, int);
137 static void	zs_modem(struct zs_chanstate *, int);
138 static void	zs_loadchannelregs(volatile struct zschan *, u_char *);
139 static u_char zs_read(volatile struct zschan *, u_char);
140 static u_char zs_write(volatile struct zschan *, u_char, u_char);
141 
142 /* Console stuff. */
143 static volatile struct zschan *zs_conschan;
144 
145 #ifdef KGDB
146 /* KGDB stuff.  Must reboot to change zs_kgdbunit. */
147 extern int kgdb_dev, kgdb_rate;
148 static int zs_kgdb_savedspeed;
149 static void zs_checkkgdb(int, struct zs_chanstate *, struct tty *);
150 #endif
151 
152 static volatile struct zsdevice *zsaddr[NZS];	/* XXX, but saves work */
153 
154 /*
155  * Console keyboard L1-A processing is done in the hardware interrupt code,
156  * so we need to duplicate some of the console keyboard decode state.  (We
157  * must not use the regular state as the hardware code keeps ahead of the
158  * software state: the software state tracks the most recent ring input but
159  * the hardware state tracks the most recent ZSCC input.)  See also kbd.h.
160  */
161 static struct conk_state {	/* console keyboard state */
162 	char	conk_id;	/* true => ID coming up (console only) */
163 	char	conk_l1;	/* true => L1 pressed (console only) */
164 } zsconk_state;
165 
166 int zshardscope;
167 int zsshortcuts;		/* number of "shortcut" software interrupts */
168 
169 /*
170  * Match slave number to zs unit number, so that misconfiguration will
171  * not set up the keyboard as ttya, etc.
172  */
173 static int
174 zsmatch(struct device *parent, struct cfdata *cf, void *aux)
175 {
176 	struct obio_cf_loc *obio_loc;
177 	caddr_t zs_addr;
178 
179 	obio_loc = (struct obio_cf_loc *) CFDATA_LOC(cf);
180 	zs_addr = (caddr_t) obio_loc->obio_addr;
181 	return !obio_probe_byte(zs_addr);
182 }
183 
184 /*
185  * Attach a found zs.
186  *
187  * USE ROM PROPERTIES port-a-ignore-cd AND port-b-ignore-cd FOR
188  * SOFT CARRIER, AND keyboard PROPERTY FOR KEYBOARD/MOUSE?
189  */
190 static void
191 zsattach(struct device *parent, struct device *dev, void *aux)
192 {
193 	struct obio_cf_loc *obio_loc = OBIO_LOC(dev);
194 	register int zs = dev->dv_unit, unit;
195 	register struct zsinfo *zi;
196 	register struct zs_chanstate *cs;
197 	register volatile struct zsdevice *addr;
198 	register struct tty *tp, *ctp;
199 	int softcar;
200 	static int didintr;
201 	caddr_t obio_addr;
202 
203 	obio_addr = (caddr_t)obio_loc->obio_addr;
204 	obio_print(obio_addr, ZSSOFT_PRI);
205 	printf(" hwpri %d\n", ZSHARD_PRI);
206 
207 	if ((addr = zsaddr[zs]) == NULL) {
208 		zsaddr[zs] = addr = (struct zsdevice *)
209 			obio_alloc(obio_addr, OBIO_ZS_SIZE, OBIO_WRITE);
210 	}
211 
212 	if (!didintr) {
213 		didintr = 1;
214 		isr_add(ZSSOFT_PRI, zssoft, 0);
215 		isr_add(ZSHARD_PRI, zshard, 0);
216 	}
217 
218 	zi = (struct zsinfo *)dev;
219 	zi->zi_zs = addr;
220 	unit = zs * 2;
221 	cs = zi->zi_cs;
222 
223 	if(!zs_tty[unit])
224 		zs_tty[unit] = ttymalloc();
225 	tp = zs_tty[unit];
226 	if(!zs_tty[unit+1])
227 		zs_tty[unit+1] = ttymalloc();
228 
229 	if (unit == 0) {
230 		softcar = 0;
231 	} else
232 		softcar = dev->dv_cfdata->cf_flags;
233 
234 	/* link into interrupt list with order (A,B) (B=A+1) */
235 	cs[0].cs_next = &cs[1];
236 	cs[1].cs_next = zslist;
237 	zslist = cs;
238 
239 	cs->cs_unit = unit;
240 	cs->cs_zc = &addr->zs_chan[CHAN_A];
241 	cs->cs_speed = zs_getspeed(cs->cs_zc);
242 #ifdef	DEBUG
243 	mon_printf("zs%da speed %d ",  zs, cs->cs_speed);
244 #endif
245 	cs->cs_softcar = softcar & 1;
246 #if 0
247 	/* XXX - Drop carrier here? -gwr */
248 	zs_modem(cs, cs->cs_softcar ? 1 : 0);
249 #endif
250 	cs->cs_ttyp = tp;
251 	tp->t_dev = makedev(ZSMAJOR, unit);
252 	tp->t_oproc = zsstart;
253 	tp->t_param = zsparam;
254 	if (cs->cs_zc == zs_conschan) {
255 		/* This unit is the console. */
256 		cs->cs_consio = 1;
257 		cs->cs_brkabort = 1;
258 		cs->cs_softcar = 1;
259 	} else {
260 		/* Can not run kgdb on the console? */
261 #ifdef KGDB
262 		zs_checkkgdb(unit, cs, tp);
263 #endif
264 	}
265 	if (unit == ZS_KBD) {
266 		/*
267 		 * Keyboard: tell /dev/kbd driver how to talk to us.
268 		 */
269 		tp->t_ispeed = tp->t_ospeed = cs->cs_speed;
270 		tp->t_cflag = CS8;
271 		kbd_serial(tp, zsiopen, zsiclose);
272 		cs->cs_conk = 1;		/* do L1-A processing */
273 	}
274 	unit++;
275 	cs++;
276 	tp = zs_tty[unit];
277 
278 	cs->cs_unit = unit;
279 	cs->cs_zc = &addr->zs_chan[CHAN_B];
280 	cs->cs_speed = zs_getspeed(cs->cs_zc);
281 #ifdef	DEBUG
282 	mon_printf("zs%db speed %d\n", zs, cs->cs_speed);
283 #endif
284 	cs->cs_softcar = softcar & 2;
285 #if 0
286 	/* XXX - Drop carrier here? -gwr */
287 	zs_modem(cs, cs->cs_softcar ? 1 : 0);
288 #endif
289 	cs->cs_ttyp = tp;
290 	tp->t_dev = makedev(ZSMAJOR, unit);
291 	tp->t_oproc = zsstart;
292 	tp->t_param = zsparam;
293 	if (cs->cs_zc == zs_conschan) {
294 		/* This unit is the console. */
295 		cs->cs_consio = 1;
296 		cs->cs_brkabort = 1;
297 		cs->cs_softcar = 1;
298 	} else {
299 		/* Can not run kgdb on the console? */
300 #ifdef KGDB
301 		zs_checkkgdb(unit, cs, tp);
302 #endif
303 	}
304 	if (unit == ZS_MOUSE) {
305 		/*
306 		 * Mouse: tell /dev/mouse driver how to talk to us.
307 		 */
308 		tp->t_ispeed = tp->t_ospeed = cs->cs_speed;
309 		tp->t_cflag = CS8;
310 		ms_serial(tp, zsiopen, zsiclose);
311 	}
312 }
313 
314 /*
315  * Put a channel in a known state.  Interrupts may be left disabled
316  * or enabled, as desired.
317  */
318 static void
319 zs_reset(zc, inten, speed)
320 	volatile struct zschan *zc;
321 	int inten, speed;
322 {
323 	int tconst;
324 	static u_char reg[16] = {
325 		0,
326 		0,
327 		0,
328 		ZSWR3_RX_8 | ZSWR3_RX_ENABLE,
329 		ZSWR4_CLK_X16 | ZSWR4_ONESB | ZSWR4_EVENP,
330 		ZSWR5_TX_8 | ZSWR5_TX_ENABLE,
331 		0,
332 		0,
333 		0,
334 		0,
335 		ZSWR10_NRZ,
336 		ZSWR11_TXCLK_BAUD | ZSWR11_RXCLK_BAUD,
337 		0,
338 		0,
339 		ZSWR14_BAUD_FROM_PCLK | ZSWR14_BAUD_ENA,
340 		ZSWR15_BREAK_IE | ZSWR15_DCD_IE,
341 	};
342 
343 	reg[9] = inten ? ZSWR9_MASTER_IE | ZSWR9_NO_VECTOR : ZSWR9_NO_VECTOR;
344 	tconst = BPS_TO_TCONST(PCLK / 16, speed);
345 	reg[12] = tconst;
346 	reg[13] = tconst >> 8;
347 	zs_loadchannelregs(zc, reg);
348 }
349 
350 /*
351  * Console support
352  */
353 
354 /*
355  * Used by the kd driver to find out if it can work.
356  */
357 int
358 zscnprobe_kbd()
359 {
360 	if (zs1_va == NULL) {
361 		mon_printf("zscnprobe_kbd: zs1 not yet mapped\n");
362 		return CN_DEAD;
363 	}
364 	zsaddr[1] = (struct zsdevice *)zs1_va;
365 	return CN_INTERNAL;
366 }
367 
368 /*
369  * This is the console probe routine for ttya and ttyb.
370  */
371 static int
372 zscnprobe(struct consdev *cn, int unit)
373 {
374 	int maj, eeCons;
375 
376 	if (zs0_va == NULL) {
377 		mon_printf("zscnprobe: zs0 not yet mapped\n");
378 		cn->cn_pri = CN_DEAD;
379 		return 0;
380 	}
381 	zsaddr[0] = (struct zsdevice *)zs0_va;
382 	/* XXX - Also try to make sure it exists? */
383 
384 	/* locate the major number */
385 	for (maj = 0; maj < nchrdev; maj++)
386 		if (cdevsw[maj].d_open == zsopen)
387 			break;
388 
389 	cn->cn_dev = makedev(maj, unit);
390 
391 	/* Use EEPROM console setting to decide "remote" console. */
392 	if (eeprom_va == NULL) {
393 		mon_printf("zscnprobe: eeprom not yet mapped\n");
394 		eeCons = -1;
395 	} else {
396 		eeCons = ((struct eeprom *)eeprom_va)->eeConsole;
397 	}
398 
399 	/* Hack: EE_CONS_TTYA + 1 == EE_CONS_TTYB */
400 	if (eeCons == (EE_CONS_TTYA + unit)) {
401 		cn->cn_pri = CN_REMOTE;
402 	} else {
403 		cn->cn_pri = CN_NORMAL;
404 	}
405 	return (0);
406 }
407 
408 /* This is the constab entry for TTYA. */
409 int
410 zscnprobe_a(struct consdev *cn)
411 {
412 	return (zscnprobe(cn, 0));
413 }
414 
415 /* This is the constab entry for TTYB. */
416 int
417 zscnprobe_b(struct consdev *cn)
418 {
419 	return (zscnprobe(cn, 1));
420 }
421 
422 /* Attach as console.  Also set zs_conschan */
423 int
424 zscninit(struct consdev *cn)
425 {
426 	int unit;
427 	volatile struct zsdevice *addr;
428 
429 	unit = minor(cn->cn_dev) & 1;
430 	addr = (struct zsdevice *)zs0_va;
431 	zs_conschan = ((unit == 0) ?
432 				   &addr->zs_chan[CHAN_A] :
433 				   &addr->zs_chan[CHAN_B] );
434 
435 	mon_printf("console on zs0 (tty%c)\n", unit + 'a');
436 }
437 
438 
439 /*
440  * Polled console input putchar.
441  */
442 int
443 zscngetc(dev)
444 	dev_t dev;
445 {
446 	register volatile struct zschan *zc = zs_conschan;
447 	register int s, c;
448 
449 	if (zc == NULL)
450 		return (0);
451 
452 	s = splhigh();
453 	while ((zc->zc_csr & ZSRR0_RX_READY) == 0)
454 		ZS_DELAY();
455 	ZS_DELAY();
456 	c = zc->zc_data;
457 	splx(s);
458 	return (c);
459 }
460 
461 /*
462  * Polled console output putchar.
463  */
464 int
465 zscnputc(dev, c)
466 	dev_t dev;
467 	int c;
468 {
469 	register volatile struct zschan *zc = zs_conschan;
470 	register int s;
471 
472 	if (zc == NULL) {
473 		s = splhigh();
474 		mon_putchar(c);
475 		splx(s);
476 		return (0);
477 	}
478 
479 	s = splhigh();
480 	while ((zc->zc_csr & ZSRR0_TX_READY) == 0)
481 		ZS_DELAY();
482 	ZS_DELAY();
483 	zc->zc_data = c;
484 	ZS_DELAY();
485 	splx(s);
486 }
487 
488 #ifdef KGDB
489 /*
490  * The kgdb zs port, if any, was altered at boot time (see zs_kgdb_init).
491  * Pick up the current speed and character size and restore the original
492  * speed.
493  */
494 static void
495 zs_checkkgdb(int unit, struct zs_chanstate *cs, struct tty *tp)
496 {
497 
498 	if (kgdb_dev == makedev(ZSMAJOR, unit)) {
499 		tp->t_ispeed = tp->t_ospeed = kgdb_rate;
500 		tp->t_cflag = CS8;
501 		cs->cs_kgdb = 1;
502 		cs->cs_speed = zs_kgdb_savedspeed;
503 		(void) zsparam(tp, &tp->t_termios);
504 	}
505 }
506 #endif
507 
508 /*
509  * Compute the current baud rate given a ZSCC channel.
510  */
511 static int
512 zs_getspeed(zc)
513 	register volatile struct zschan *zc;
514 {
515 	register int tconst;
516 
517 	tconst = ZS_READ(zc, 12);
518 	tconst |= ZS_READ(zc, 13) << 8;
519 	return (TCONST_TO_BPS(PCLK / 16, tconst));
520 }
521 
522 
523 /*
524  * Do an internal open.
525  */
526 static void
527 zsiopen(struct tty *tp)
528 {
529 
530 	(void) zsparam(tp, &tp->t_termios);
531 	ttsetwater(tp);
532 	tp->t_state = TS_ISOPEN | TS_CARR_ON;
533 }
534 
535 /*
536  * Do an internal close.  Eventually we should shut off the chip when both
537  * ports on it are closed.
538  */
539 static void
540 zsiclose(struct tty *tp)
541 {
542 
543 	ttylclose(tp, 0);	/* ??? */
544 	ttyclose(tp);		/* ??? */
545 	tp->t_state = 0;
546 }
547 
548 
549 /*
550  * Open a zs serial port.  This interface may not be used to open
551  * the keyboard and mouse ports. (XXX)
552  */
553 int
554 zsopen(dev_t dev, int flags, int mode, struct proc *p)
555 {
556 	register struct tty *tp;
557 	register struct zs_chanstate *cs;
558 	struct zsinfo *zi;
559 	int unit = minor(dev), zs = unit >> 1, error, s;
560 
561 #ifdef	DEBUG
562 	mon_printf("zs_open\n");
563 #endif
564 	if (zs >= zscd.cd_ndevs || (zi = zscd.cd_devs[zs]) == NULL ||
565 	    unit == ZS_KBD || unit == ZS_MOUSE)
566 		return (ENXIO);
567 	cs = &zi->zi_cs[unit & 1];
568 #if 0
569 	/* The kd driver avoids the need for this hack. */
570 	if (cs->cs_consio)
571 		return (ENXIO);		/* ??? */
572 #endif
573 	tp = cs->cs_ttyp;
574 	s = spltty();
575 	if ((tp->t_state & TS_ISOPEN) == 0) {
576 		ttychars(tp);
577 		if (tp->t_ispeed == 0) {
578 			tp->t_iflag = TTYDEF_IFLAG;
579 			tp->t_oflag = TTYDEF_OFLAG;
580 			tp->t_cflag = TTYDEF_CFLAG;
581 			tp->t_lflag = TTYDEF_LFLAG;
582 			tp->t_ispeed = tp->t_ospeed = cs->cs_speed;
583 		}
584 		(void) zsparam(tp, &tp->t_termios);
585 		ttsetwater(tp);
586 	} else if (tp->t_state & TS_XCLUDE && p->p_ucred->cr_uid != 0) {
587 		splx(s);
588 		return (EBUSY);
589 	}
590 	error = 0;
591 #ifdef	DEBUG
592 	mon_printf("wait for carrier...\n");
593 #endif
594 	for (;;) {
595 		/* loop, turning on the device, until carrier present */
596 		zs_modem(cs, 1);
597 		/* May never get status intr if carrier already on. -gwr */
598 		if (cs->cs_zc->zc_csr & ZSRR0_DCD)
599 			tp->t_state |= TS_CARR_ON;
600 		if (cs->cs_softcar)
601 			tp->t_state |= TS_CARR_ON;
602 		if (flags & O_NONBLOCK || tp->t_cflag & CLOCAL ||
603 		    tp->t_state & TS_CARR_ON)
604 			break;
605 		tp->t_state |= TS_WOPEN;
606 		if (error = ttysleep(tp, (caddr_t)&tp->t_rawq, TTIPRI | PCATCH,
607 		    ttopen, 0))
608 			break;
609 	}
610 #ifdef	DEBUG
611 	mon_printf("...carrier %s\n",
612 			   (tp->t_state & TS_CARR_ON) ? "on" : "off");
613 #endif
614 	splx(s);
615 	if (error == 0)
616 		error = linesw[tp->t_line].l_open(dev, tp);
617 	if (error)
618 		zs_modem(cs, 0);
619 	return (error);
620 }
621 
622 /*
623  * Close a zs serial port.
624  */
625 int
626 zsclose(dev_t dev, int flags, int mode, struct proc *p)
627 {
628 	register struct zs_chanstate *cs;
629 	register struct tty *tp;
630 	struct zsinfo *zi;
631 	int unit = minor(dev), s;
632 
633 #ifdef	DEBUG
634 	mon_printf("zs_close\n");
635 #endif
636 	zi = zscd.cd_devs[unit >> 1];
637 	cs = &zi->zi_cs[unit & 1];
638 	tp = cs->cs_ttyp;
639 	linesw[tp->t_line].l_close(tp, flags);
640 	if (tp->t_cflag & HUPCL || tp->t_state & TS_WOPEN ||
641 	    (tp->t_state & TS_ISOPEN) == 0) {
642 		zs_modem(cs, 0);
643 		/* hold low for 1 second */
644 		(void) tsleep((caddr_t)cs, TTIPRI, ttclos, hz);
645 	}
646 	if (cs->cs_creg[5] & ZSWR5_BREAK)
647 	{
648 		s = splzs();
649 		cs->cs_preg[5] &= ~ZSWR5_BREAK;
650 		cs->cs_creg[5] &= ~ZSWR5_BREAK;
651 		ZS_WRITE(cs->cs_zc, 5, cs->cs_creg[5]);
652 		splx(s);
653 	}
654 	ttyclose(tp);
655 #ifdef KGDB
656 	/* Reset the speed if we're doing kgdb on this port */
657 	if (cs->cs_kgdb) {
658 		tp->t_ispeed = tp->t_ospeed = kgdb_rate;
659 		(void) zsparam(tp, &tp->t_termios);
660 	}
661 #endif
662 	return (0);
663 }
664 
665 /*
666  * Read/write zs serial port.
667  */
668 int
669 zsread(dev_t dev, struct uio *uio, int flags)
670 {
671 	register struct tty *tp = zs_tty[minor(dev)];
672 
673 	return (linesw[tp->t_line].l_read(tp, uio, flags));
674 }
675 
676 int
677 zswrite(dev_t dev, struct uio *uio, int flags)
678 {
679 	register struct tty *tp = zs_tty[minor(dev)];
680 
681 	return (linesw[tp->t_line].l_write(tp, uio, flags));
682 }
683 
684 /*
685  * ZS hardware interrupt.  Scan all ZS channels.  NB: we know here that
686  * channels are kept in (A,B) pairs.
687  *
688  * Do just a little, then get out; set a software interrupt if more
689  * work is needed.
690  *
691  * We deliberately ignore the vectoring Zilog gives us, and match up
692  * only the number of `reset interrupt under service' operations, not
693  * the order.
694  */
695 /* ARGSUSED */
696 int
697 zshard(int intrarg)
698 {
699 	register struct zs_chanstate *a;
700 #define	b (a + 1)
701 	register volatile struct zschan *zc;
702 	register int rr3, intflags = 0, v, i;
703 	static int zsrint(struct zs_chanstate *, volatile struct zschan *);
704 	static int zsxint(struct zs_chanstate *, volatile struct zschan *);
705 	static int zssint(struct zs_chanstate *, volatile struct zschan *);
706 
707 	for (a = zslist; a != NULL; a = b->cs_next) {
708 		rr3 = ZS_READ(a->cs_zc, 3);
709 
710 		/* XXX - This should loop to empty the on-chip fifo. */
711 		if (rr3 & (ZSRR3_IP_A_RX|ZSRR3_IP_A_TX|ZSRR3_IP_A_STAT)) {
712 			intflags |= 2;
713 			zc = a->cs_zc;
714 			i = a->cs_rbput;
715 			if (rr3 & ZSRR3_IP_A_RX && (v = zsrint(a, zc)) != 0) {
716 				a->cs_rbuf[i++ & ZLRB_RING_MASK] = v;
717 				intflags |= 1;
718 			}
719 			if (rr3 & ZSRR3_IP_A_TX && (v = zsxint(a, zc)) != 0) {
720 				a->cs_rbuf[i++ & ZLRB_RING_MASK] = v;
721 				intflags |= 1;
722 			}
723 			if (rr3 & ZSRR3_IP_A_STAT && (v = zssint(a, zc)) != 0) {
724 				a->cs_rbuf[i++ & ZLRB_RING_MASK] = v;
725 				intflags |= 1;
726 			}
727 			a->cs_rbput = i;
728 		}
729 
730 		/* XXX - This should loop to empty the on-chip fifo. */
731 		if (rr3 & (ZSRR3_IP_B_RX|ZSRR3_IP_B_TX|ZSRR3_IP_B_STAT)) {
732 			intflags |= 2;
733 			zc = b->cs_zc;
734 			i = b->cs_rbput;
735 			if (rr3 & ZSRR3_IP_B_RX && (v = zsrint(b, zc)) != 0) {
736 				b->cs_rbuf[i++ & ZLRB_RING_MASK] = v;
737 				intflags |= 1;
738 			}
739 			if (rr3 & ZSRR3_IP_B_TX && (v = zsxint(b, zc)) != 0) {
740 				b->cs_rbuf[i++ & ZLRB_RING_MASK] = v;
741 				intflags |= 1;
742 			}
743 			if (rr3 & ZSRR3_IP_B_STAT && (v = zssint(b, zc)) != 0) {
744 				b->cs_rbuf[i++ & ZLRB_RING_MASK] = v;
745 				intflags |= 1;
746 			}
747 			b->cs_rbput = i;
748 		}
749 	}
750 #undef b
751 	if (intflags & 1) {
752 	    isr_soft_request(ZSSOFT_PRI);
753 	}
754 	return (intflags & 2);
755 }
756 
757 static int
758 zsrint(register struct zs_chanstate *cs, register volatile struct zschan *zc)
759 {
760 	register int c = zc->zc_data;
761 
762 	if (cs->cs_conk) {
763 		register struct conk_state *conk = &zsconk_state;
764 
765 		/*
766 		 * Check here for console abort function, so that we
767 		 * can abort even when interrupts are locking up the
768 		 * machine.
769 		 */
770 		if (c == KBD_RESET) {
771 			conk->conk_id = 1;	/* ignore next byte */
772 			conk->conk_l1 = 0;
773 		} else if (conk->conk_id)
774 			conk->conk_id = 0;	/* stop ignoring bytes */
775 		else if (c == KBD_L1)
776 			conk->conk_l1 = 1;	/* L1 went down */
777 		else if (c == (KBD_L1|KBD_UP))
778 			conk->conk_l1 = 0;	/* L1 went up */
779 		else if (c == KBD_A && conk->conk_l1) {
780 			zsabort();
781 			conk->conk_l1 = 0;	/* we never see the up */
782 			goto clearit;		/* eat the A after L1-A */
783 		}
784 	}
785 #ifdef KGDB
786 	if (c == FRAME_START && cs->cs_kgdb &&
787 	    (cs->cs_ttyp->t_state & TS_ISOPEN) == 0) {
788 		zskgdb(cs->cs_unit);
789 		goto clearit;
790 	}
791 #endif
792 	/* compose receive character and status */
793 	c <<= 8;
794 	c |= ZS_READ(zc, 1);
795 
796 	/* clear receive error & interrupt condition */
797 	zc->zc_csr = ZSWR0_RESET_ERRORS;
798 	zc->zc_csr = ZSWR0_CLR_INTR;
799 
800 	return (ZRING_MAKE(ZRING_RINT, c));
801 
802 clearit:
803 	zc->zc_csr = ZSWR0_RESET_ERRORS;
804 	zc->zc_csr = ZSWR0_CLR_INTR;
805 	return (0);
806 }
807 
808 static int
809 zsxint(register struct zs_chanstate *cs, register volatile struct zschan *zc)
810 {
811 	register int i = cs->cs_tbc;
812 
813 	if (i == 0) {
814 		zc->zc_csr = ZSWR0_RESET_TXINT;
815 		zc->zc_csr = ZSWR0_CLR_INTR;
816 		return (ZRING_MAKE(ZRING_XINT, 0));
817 	}
818 	cs->cs_tbc = i - 1;
819 	zc->zc_data = *cs->cs_tba++;
820 	zc->zc_csr = ZSWR0_CLR_INTR;
821 	return (0);
822 }
823 
824 static int
825 zssint(register struct zs_chanstate *cs, register volatile struct zschan *zc)
826 {
827 	register int rr0;
828 
829 	rr0 = zc->zc_csr;
830 	zc->zc_csr = ZSWR0_RESET_STATUS;
831 	zc->zc_csr = ZSWR0_CLR_INTR;
832 	/*
833 	 * The chip's hardware flow control is, as noted in zsreg.h,
834 	 * busted---if the DCD line goes low the chip shuts off the
835 	 * receiver (!).  If we want hardware CTS flow control but do
836 	 * not have it, and carrier is now on, turn HFC on; if we have
837 	 * HFC now but carrier has gone low, turn it off.
838 	 */
839 	if (rr0 & ZSRR0_DCD) {
840 		if (cs->cs_ttyp->t_cflag & CCTS_OFLOW &&
841 		    (cs->cs_creg[3] & ZSWR3_HFC) == 0) {
842 			cs->cs_creg[3] |= ZSWR3_HFC;
843 			ZS_WRITE(zc, 3, cs->cs_creg[3]);
844 		}
845 	} else {
846 		if (cs->cs_creg[3] & ZSWR3_HFC) {
847 			cs->cs_creg[3] &= ~ZSWR3_HFC;
848 			ZS_WRITE(zc, 3, cs->cs_creg[3]);
849 		}
850 	}
851 	if ((rr0 & ZSRR0_BREAK) && cs->cs_brkabort) {
852 		/* Wait for end of break to avoid PROM abort. */
853 		while (zc->zc_csr & ZSRR0_BREAK)
854 			ZS_DELAY();
855 		zsabort();
856 		return (0);
857 	}
858 	return (ZRING_MAKE(ZRING_SINT, rr0));
859 }
860 
861 zsabort()
862 {
863 #ifdef DDB
864 	Debugger();
865 #else
866 	printf("stopping on keyboard abort\n");
867 	sun3_rom_abort();
868 #endif
869 }
870 
871 #ifdef KGDB
872 /*
873  * KGDB framing character received: enter kernel debugger.  This probably
874  * should time out after a few seconds to avoid hanging on spurious input.
875  */
876 zskgdb(int unit)
877 {
878 
879 	printf("zs%d%c: kgdb interrupt\n", unit >> 1, (unit & 1) + 'a');
880 	kgdb_connect(1);
881 }
882 #endif
883 
884 /*
885  * Print out a ring or fifo overrun error message.
886  */
887 static void
888 zsoverrun(int unit, long *ptime, char *what)
889 {
890 
891 	if (*ptime != time.tv_sec) {
892 		*ptime = time.tv_sec;
893 		log(LOG_WARNING, "zs%d%c: %s overrun\n", unit >> 1,
894 		    (unit & 1) + 'a', what);
895 	}
896 }
897 
898 /*
899  * ZS software interrupt.  Scan all channels for deferred interrupts.
900  */
901 int
902 zssoft(int arg)
903 {
904 	register struct zs_chanstate *cs;
905 	register volatile struct zschan *zc;
906 	register struct linesw *line;
907 	register struct tty *tp;
908 	register int get, n, c, cc, unit, s;
909 
910 	isr_soft_clear(ZSSOFT_PRI);
911 
912 	for (cs = zslist; cs != NULL; cs = cs->cs_next) {
913 		get = cs->cs_rbget;
914 again:
915 		n = cs->cs_rbput;	/* atomic */
916 		if (get == n)		/* nothing more on this line */
917 			continue;
918 		unit = cs->cs_unit;	/* set up to handle interrupts */
919 		zc = cs->cs_zc;
920 		tp = cs->cs_ttyp;
921 		line = &linesw[tp->t_line];
922 		/*
923 		 * Compute the number of interrupts in the receive ring.
924 		 * If the count is overlarge, we lost some events, and
925 		 * must advance to the first valid one.  It may get
926 		 * overwritten if more data are arriving, but this is
927 		 * too expensive to check and gains nothing (we already
928 		 * lost out; all we can do at this point is trade one
929 		 * kind of loss for another).
930 		 */
931 		n -= get;
932 		if (n > ZLRB_RING_SIZE) {
933 			zsoverrun(unit, &cs->cs_rotime, "ring");
934 			get += n - ZLRB_RING_SIZE;
935 			n = ZLRB_RING_SIZE;
936 		}
937 		while (--n >= 0) {
938 			/* race to keep ahead of incoming interrupts */
939 			c = cs->cs_rbuf[get++ & ZLRB_RING_MASK];
940 			switch (ZRING_TYPE(c)) {
941 
942 			case ZRING_RINT:
943 				c = ZRING_VALUE(c);
944 				if (c & ZSRR1_DO)
945 					zsoverrun(unit, &cs->cs_fotime, "fifo");
946 				cc = c >> 8;
947 				if (c & ZSRR1_FE)
948 					cc |= TTY_FE;
949 				if (c & ZSRR1_PE)
950 					cc |= TTY_PE;
951 				/*
952 				 * this should be done through
953 				 * bstreams	XXX gag choke
954 				 */
955 				if (unit == ZS_KBD)
956 					kbd_rint(cc);
957 				else if (unit == ZS_MOUSE)
958 					ms_rint(cc);
959 				else
960 					line->l_rint(cc, tp);
961 				break;
962 
963 			case ZRING_XINT:
964 				/*
965 				 * Transmit done: change registers and resume,
966 				 * or clear BUSY.
967 				 */
968 				if (cs->cs_heldchange) {
969 					s = splzs();
970 					c = zc->zc_csr;
971 					if ((c & ZSRR0_DCD) == 0)
972 						cs->cs_preg[3] &= ~ZSWR3_HFC;
973 					bcopy((caddr_t)cs->cs_preg,
974 					    (caddr_t)cs->cs_creg, 16);
975 					zs_loadchannelregs(zc, cs->cs_creg);
976 					splx(s);
977 					cs->cs_heldchange = 0;
978 					if (cs->cs_heldtbc &&
979 					    (tp->t_state & TS_TTSTOP) == 0) {
980 						cs->cs_tbc = cs->cs_heldtbc - 1;
981 						zc->zc_data = *cs->cs_tba++;
982 						goto again;
983 					}
984 				}
985 				tp->t_state &= ~TS_BUSY;
986 				if (tp->t_state & TS_FLUSH)
987 					tp->t_state &= ~TS_FLUSH;
988 				else
989 					ndflush(&tp->t_outq,
990 					    cs->cs_tba - tp->t_outq.c_cf);
991 				line->l_start(tp);
992 				break;
993 
994 			case ZRING_SINT:
995 				/*
996 				 * Status line change.  HFC bit is run in
997 				 * hardware interrupt, to avoid locking
998 				 * at splzs here.
999 				 */
1000 				c = ZRING_VALUE(c);
1001 				if ((c ^ cs->cs_rr0) & ZSRR0_DCD) {
1002 					cc = (c & ZSRR0_DCD) != 0;
1003 					if (line->l_modem(tp, cc) == 0)
1004 						zs_modem(cs, cc);
1005 				}
1006 				cs->cs_rr0 = c;
1007 				break;
1008 
1009 			default:
1010 				log(LOG_ERR, "zs%d%c: bad ZRING_TYPE (%x)\n",
1011 				    unit >> 1, (unit & 1) + 'a', c);
1012 				break;
1013 			}
1014 		}
1015 		cs->cs_rbget = get;
1016 		goto again;
1017 	}
1018 	return (1);
1019 }
1020 
1021 int
1022 zsioctl(dev_t dev, int cmd, caddr_t data, int flag, struct proc *p)
1023 {
1024 	int unit = minor(dev);
1025 	struct zsinfo *zi = zscd.cd_devs[unit >> 1];
1026 	register struct zs_chanstate *cs = &zi->zi_cs[unit & 1];
1027 	register struct tty *tp = cs->cs_ttyp;
1028 	register int error, s;
1029 
1030 	error = linesw[tp->t_line].l_ioctl(tp, cmd, data, flag, p);
1031 	if (error >= 0)
1032 		return (error);
1033 	error = ttioctl(tp, cmd, data, flag, p);
1034 	if (error >= 0)
1035 		return (error);
1036 
1037 	switch (cmd) {
1038 
1039 	case TIOCSBRK:
1040 		{
1041 			s = splzs();
1042 			cs->cs_preg[5] |= ZSWR5_BREAK;
1043 			cs->cs_creg[5] |= ZSWR5_BREAK;
1044 			ZS_WRITE(cs->cs_zc, 5, cs->cs_creg[5]);
1045 			splx(s);
1046 			break;
1047 		}
1048 
1049 	case TIOCCBRK:
1050 		{
1051 			s = splzs();
1052 			cs->cs_preg[5] &= ~ZSWR5_BREAK;
1053 			cs->cs_creg[5] &= ~ZSWR5_BREAK;
1054 			ZS_WRITE(cs->cs_zc, 5, cs->cs_creg[5]);
1055 			splx(s);
1056 			break;
1057 		}
1058 
1059 	case TIOCSDTR:
1060 
1061 	case TIOCCDTR:
1062 
1063 	case TIOCMSET:
1064 
1065 	case TIOCMBIS:
1066 
1067 	case TIOCMBIC:
1068 
1069 	case TIOCMGET:
1070 
1071 	default:
1072 		return (ENOTTY);
1073 	}
1074 	return (0);
1075 }
1076 
1077 /*
1078  * Start or restart transmission.
1079  */
1080 static void
1081 zsstart(register struct tty *tp)
1082 {
1083 	register struct zs_chanstate *cs;
1084 	register int s, nch;
1085 	int unit = minor(tp->t_dev);
1086 	struct zsinfo *zi = zscd.cd_devs[unit >> 1];
1087 
1088 	cs = &zi->zi_cs[unit & 1];
1089 	s = spltty();
1090 
1091 	/*
1092 	 * If currently active or delaying, no need to do anything.
1093 	 */
1094 	if (tp->t_state & (TS_TIMEOUT | TS_BUSY | TS_TTSTOP))
1095 		goto out;
1096 
1097 	/*
1098 	 * If there are sleepers, and output has drained below low
1099 	 * water mark, awaken.
1100 	 */
1101 	if (tp->t_outq.c_cc <= tp->t_lowat) {
1102 		if (tp->t_state & TS_ASLEEP) {
1103 			tp->t_state &= ~TS_ASLEEP;
1104 			wakeup((caddr_t)&tp->t_outq);
1105 		}
1106 		selwakeup(&tp->t_wsel);
1107 	}
1108 
1109 	nch = ndqb(&tp->t_outq, 0);	/* XXX */
1110 	if (nch) {
1111 		register char *p = tp->t_outq.c_cf;
1112 
1113 		/* mark busy, enable tx done interrupts, & send first byte */
1114 		tp->t_state |= TS_BUSY;
1115 		(void) splzs();
1116 		cs->cs_preg[1] |= ZSWR1_TIE;
1117 		cs->cs_creg[1] |= ZSWR1_TIE;
1118 		ZS_WRITE(cs->cs_zc, 1, cs->cs_creg[1]);
1119 		cs->cs_zc->zc_data = *p;
1120 		cs->cs_tba = p + 1;
1121 		cs->cs_tbc = nch - 1;
1122 	} else {
1123 		/*
1124 		 * Nothing to send, turn off transmit done interrupts.
1125 		 * This is useful if something is doing polled output.
1126 		 */
1127 		(void) splzs();
1128 		cs->cs_preg[1] &= ~ZSWR1_TIE;
1129 		cs->cs_creg[1] &= ~ZSWR1_TIE;
1130 		ZS_WRITE(cs->cs_zc, 1, cs->cs_creg[1]);
1131 	}
1132 out:
1133 	splx(s);
1134 }
1135 
1136 /*
1137  * Stop output, e.g., for ^S or output flush.
1138  */
1139 void
1140 zsstop(register struct tty *tp, int flag)
1141 {
1142 	register struct zs_chanstate *cs;
1143 	register int s, unit = minor(tp->t_dev);
1144 	struct zsinfo *zi = zscd.cd_devs[unit >> 1];
1145 
1146 	cs = &zi->zi_cs[unit & 1];
1147 	s = splzs();
1148 	if (tp->t_state & TS_BUSY) {
1149 		/*
1150 		 * Device is transmitting; must stop it.
1151 		 */
1152 		cs->cs_tbc = 0;
1153 		if ((tp->t_state & TS_TTSTOP) == 0)
1154 			tp->t_state |= TS_FLUSH;
1155 	}
1156 	splx(s);
1157 }
1158 
1159 /*
1160  * Set ZS tty parameters from termios.
1161  *
1162  * This routine makes use of the fact that only registers
1163  * 1, 3, 4, 5, 9, 10, 11, 12, 13, 14, and 15 are written.
1164  */
1165 static int
1166 zsparam(register struct tty *tp, register struct termios *t)
1167 {
1168 	int unit = minor(tp->t_dev);
1169 	struct zsinfo *zi = zscd.cd_devs[unit >> 1];
1170 	register struct zs_chanstate *cs = &zi->zi_cs[unit & 1];
1171 	register int tmp, tmp5, cflag, s;
1172 
1173 	/*
1174 	 * Because PCLK is only run at 4.9 MHz, the fastest we
1175 	 * can go is 51200 baud (this corresponds to TC=1).
1176 	 * This is somewhat unfortunate as there is no real
1177 	 * reason we should not be able to handle higher rates.
1178 	 */
1179 	tmp = t->c_ospeed;
1180 	if (tmp < 0 || (t->c_ispeed && t->c_ispeed != tmp))
1181 		return (EINVAL);
1182 	if (tmp == 0) {
1183 		/* stty 0 => drop DTR and RTS */
1184 		zs_modem(cs, 0);
1185 		return (0);
1186 	}
1187 	tmp = BPS_TO_TCONST(PCLK / 16, tmp);
1188 	if (tmp < 2)
1189 		return (EINVAL);
1190 
1191 	cflag = t->c_cflag;
1192 	tp->t_ispeed = tp->t_ospeed = TCONST_TO_BPS(PCLK / 16, tmp);
1193 	tp->t_cflag = cflag;
1194 
1195 	/*
1196 	 * Block interrupts so that state will not
1197 	 * be altered until we are done setting it up.
1198 	 */
1199 	s = splzs();
1200 	cs->cs_preg[12] = tmp;
1201 	cs->cs_preg[13] = tmp >> 8;
1202 	cs->cs_preg[1] = ZSWR1_RIE | ZSWR1_TIE | ZSWR1_SIE;
1203 	switch (cflag & CSIZE) {
1204 	case CS5:
1205 		tmp = ZSWR3_RX_5;
1206 		tmp5 = ZSWR5_TX_5;
1207 		break;
1208 	case CS6:
1209 		tmp = ZSWR3_RX_6;
1210 		tmp5 = ZSWR5_TX_6;
1211 		break;
1212 	case CS7:
1213 		tmp = ZSWR3_RX_7;
1214 		tmp5 = ZSWR5_TX_7;
1215 		break;
1216 	case CS8:
1217 	default:
1218 		tmp = ZSWR3_RX_8;
1219 		tmp5 = ZSWR5_TX_8;
1220 		break;
1221 	}
1222 
1223 	/*
1224 	 * Output hardware flow control on the chip is horrendous: if
1225 	 * carrier detect drops, the receiver is disabled.  Hence we
1226 	 * can only do this when the carrier is on.
1227 	 */
1228 	if (cflag & CCTS_OFLOW && cs->cs_zc->zc_csr & ZSRR0_DCD)
1229 		tmp |= ZSWR3_HFC | ZSWR3_RX_ENABLE;
1230 	else
1231 		tmp |= ZSWR3_RX_ENABLE;
1232 	cs->cs_preg[3] = tmp;
1233 	cs->cs_preg[5] = tmp5 | ZSWR5_TX_ENABLE | ZSWR5_DTR | ZSWR5_RTS;
1234 
1235 	tmp = ZSWR4_CLK_X16 | (cflag & CSTOPB ? ZSWR4_TWOSB : ZSWR4_ONESB);
1236 	if ((cflag & PARODD) == 0)
1237 		tmp |= ZSWR4_EVENP;
1238 	if (cflag & PARENB)
1239 		tmp |= ZSWR4_PARENB;
1240 	cs->cs_preg[4] = tmp;
1241 	cs->cs_preg[9] = ZSWR9_MASTER_IE | ZSWR9_NO_VECTOR;
1242 	cs->cs_preg[10] = ZSWR10_NRZ;
1243 	cs->cs_preg[11] = ZSWR11_TXCLK_BAUD | ZSWR11_RXCLK_BAUD;
1244 	cs->cs_preg[14] = ZSWR14_BAUD_FROM_PCLK | ZSWR14_BAUD_ENA;
1245 	cs->cs_preg[15] = ZSWR15_BREAK_IE | ZSWR15_DCD_IE;
1246 
1247 	/*
1248 	 * If nothing is being transmitted, set up new current values,
1249 	 * else mark them as pending.
1250 	 */
1251 	if (cs->cs_heldchange == 0) {
1252 		if (cs->cs_ttyp->t_state & TS_BUSY) {
1253 			cs->cs_heldtbc = cs->cs_tbc;
1254 			cs->cs_tbc = 0;
1255 			cs->cs_heldchange = 1;
1256 		} else {
1257 			bcopy((caddr_t)cs->cs_preg, (caddr_t)cs->cs_creg, 16);
1258 			zs_loadchannelregs(cs->cs_zc, cs->cs_creg);
1259 		}
1260 	}
1261 	splx(s);
1262 	return (0);
1263 }
1264 
1265 /*
1266  * Raise or lower modem control (DTR/RTS) signals.  If a character is
1267  * in transmission, the change is deferred.
1268  */
1269 static void
1270 zs_modem(struct zs_chanstate *cs, int onoff)
1271 {
1272 	int s, bis, and;
1273 
1274 	if (onoff) {
1275 		bis = ZSWR5_DTR | ZSWR5_RTS;
1276 		and = ~0;
1277 	} else {
1278 		bis = 0;
1279 		and = ~(ZSWR5_DTR | ZSWR5_RTS);
1280 	}
1281 	s = splzs();
1282 	cs->cs_preg[5] = (cs->cs_preg[5] | bis) & and;
1283 	if (cs->cs_heldchange == 0) {
1284 		if (cs->cs_ttyp->t_state & TS_BUSY) {
1285 			cs->cs_heldtbc = cs->cs_tbc;
1286 			cs->cs_tbc = 0;
1287 			cs->cs_heldchange = 1;
1288 		} else {
1289 			cs->cs_creg[5] = (cs->cs_creg[5] | bis) & and;
1290 			ZS_WRITE(cs->cs_zc, 5, cs->cs_creg[5]);
1291 		}
1292 	}
1293 	splx(s);
1294 }
1295 
1296 /*
1297  * Write the given register set to the given zs channel in the proper order.
1298  * The channel must not be transmitting at the time.  The receiver will
1299  * be disabled for the time it takes to write all the registers.
1300  */
1301 static void
1302 zs_loadchannelregs(volatile struct zschan *zc, u_char *reg)
1303 {
1304 	int i;
1305 
1306 	zc->zc_csr = ZSM_RESET_ERR;	/* reset error condition */
1307 	i = zc->zc_data;		/* drain fifo */
1308 	i = zc->zc_data;
1309 	i = zc->zc_data;
1310 	ZS_WRITE(zc, 4, reg[4]);
1311 	ZS_WRITE(zc, 10, reg[10]);
1312 	ZS_WRITE(zc, 3, reg[3] & ~ZSWR3_RX_ENABLE);
1313 	ZS_WRITE(zc, 5, reg[5] & ~ZSWR5_TX_ENABLE);
1314 	ZS_WRITE(zc, 1, reg[1]);
1315 	ZS_WRITE(zc, 9, reg[9]);
1316 	ZS_WRITE(zc, 11, reg[11]);
1317 	ZS_WRITE(zc, 12, reg[12]);
1318 	ZS_WRITE(zc, 13, reg[13]);
1319 	ZS_WRITE(zc, 14, reg[14]);
1320 	ZS_WRITE(zc, 15, reg[15]);
1321 	ZS_WRITE(zc, 3, reg[3]);
1322 	ZS_WRITE(zc, 5, reg[5]);
1323 }
1324 
1325 static u_char
1326 zs_read(zc, reg)
1327 	volatile struct zschan *zc;
1328 	u_char reg;
1329 {
1330 	u_char val;
1331 
1332 	zc->zc_csr = reg;
1333 	ZS_DELAY();
1334 	val = zc->zc_csr;
1335 	ZS_DELAY();
1336 	return val;
1337 }
1338 
1339 static u_char
1340 zs_write(zc, reg, val)
1341 	volatile struct zschan *zc;
1342 	u_char reg, val;
1343 {
1344 	zc->zc_csr = reg;
1345 	ZS_DELAY();
1346 	zc->zc_csr = val;
1347 	ZS_DELAY();
1348 	return val;
1349 }
1350 
1351 #ifdef KGDB
1352 /*
1353  * Get a character from the given kgdb channel.  Called at splhigh().
1354  */
1355 static int
1356 zs_kgdb_getc(void *arg)
1357 {
1358 	register volatile struct zschan *zc = (volatile struct zschan *)arg;
1359 
1360 	while ((zc->zc_csr & ZSRR0_RX_READY) == 0)
1361 		continue;
1362 	return (zc->zc_data);
1363 }
1364 
1365 /*
1366  * Put a character to the given kgdb channel.  Called at splhigh().
1367  */
1368 static void
1369 zs_kgdb_putc(void *arg, int c)
1370 {
1371 	register volatile struct zschan *zc = (volatile struct zschan *)arg;
1372 
1373 	while ((zc->zc_csr & ZSRR0_TX_READY) == 0)
1374 		continue;
1375 	zc->zc_data = c;
1376 }
1377 
1378 /*
1379  * Set up for kgdb; called at boot time before configuration.
1380  * KGDB interrupts will be enabled later when zs0 is configured.
1381  */
1382 void
1383 zs_kgdb_init()
1384 {
1385 	volatile struct zsdevice *addr;
1386 	volatile struct zschan *zc;
1387 	int unit, zs;
1388 
1389 	if (major(kgdb_dev) != ZSMAJOR)
1390 		return;
1391 	unit = minor(kgdb_dev);
1392 	/*
1393 	 * Unit must be 0 or 1 (zs0).
1394 	 */
1395 	if ((unsigned)unit >= ZS_KBD) {
1396 		printf("zs_kgdb_init: bad minor dev %d\n", unit);
1397 		return;
1398 	}
1399 	zs = unit >> 1;
1400 	unit &= 1;
1401 
1402 	if ((addr = zs0_va) == NULL)
1403 		panic("kbdb_attach: zs0 not yet mapped");
1404 
1405 	zc = unit == 0 ? &addr->zs_chan[CHAN_A] : &addr->zs_chan[CHAN_B];
1406 	zs_kgdb_savedspeed = zs_getspeed(zc);
1407 	printf("zs_kgdb_init: attaching zs%d%c at %d baud\n",
1408 	    zs, unit + 'a', kgdb_rate);
1409 	zs_reset(zc, 1, kgdb_rate);
1410 	kgdb_attach(zs_kgdb_getc, zs_kgdb_putc, (void *)zc);
1411 }
1412 #endif /* KGDB */
1413