xref: /netbsd-src/sys/arch/mipsco/obio/zs.c (revision d710132b4b8ce7f7cccaaf660cb16aa16b4077a0)
1 /*	$NetBSD: zs.c,v 1.16 2003/01/28 12:35:32 pk Exp $	*/
2 
3 /*-
4  * Copyright (c) 1996, 2000 The NetBSD Foundation, Inc.
5  * All rights reserved.
6  *
7  * This code is derived from software contributed to The NetBSD Foundation
8  * by Gordon W. Ross and Wayne Knowles
9  *
10  * Redistribution and use in source and binary forms, with or without
11  * modification, are permitted provided that the following conditions
12  * are met:
13  * 1. Redistributions of source code must retain the above copyright
14  *    notice, this list of conditions and the following disclaimer.
15  * 2. Redistributions in binary form must reproduce the above copyright
16  *    notice, this list of conditions and the following disclaimer in the
17  *    documentation and/or other materials provided with the distribution.
18  * 3. All advertising materials mentioning features or use of this software
19  *    must display the following acknowledgement:
20  *        This product includes software developed by the NetBSD
21  *        Foundation, Inc. and its contributors.
22  * 4. Neither the name of The NetBSD Foundation nor the names of its
23  *    contributors may be used to endorse or promote products derived
24  *    from this software without specific prior written permission.
25  *
26  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
27  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
28  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
29  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
30  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
31  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
32  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
33  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
34  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
35  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
36  * POSSIBILITY OF SUCH DAMAGE.
37  */
38 
39 /*
40  * Zilog Z8530 Dual UART driver (machine-dependent part)
41  *
42  * Runs two serial lines per chip using slave drivers.
43  * Plain tty/async lines use the zs_async slave.
44  */
45 
46 #include "opt_ddb.h"
47 #include "opt_kgdb.h"
48 
49 #include <sys/param.h>
50 #include <sys/systm.h>
51 #include <sys/conf.h>
52 #include <sys/device.h>
53 #include <sys/file.h>
54 #include <sys/ioctl.h>
55 #include <sys/kernel.h>
56 #include <sys/proc.h>
57 #include <sys/tty.h>
58 #include <sys/time.h>
59 #include <sys/syslog.h>
60 
61 #include <machine/cpu.h>
62 #include <machine/mainboard.h>
63 #include <machine/autoconf.h>
64 #include <machine/prom.h>
65 #include <machine/z8530var.h>
66 
67 #include <dev/cons.h>
68 #include <dev/ic/z8530reg.h>
69 
70 #include "zsc.h"	/* NZSC */
71 #define NZS NZSC
72 
73 /* Make life easier for the initialized arrays here. */
74 #if NZS < 2
75 #undef  NZS
76 #define NZS 2
77 #endif
78 
79 /*
80  * Some warts needed by z8530tty.c -
81  * The default parity REALLY needs to be the same as the PROM uses,
82  * or you can not see messages done with printf during boot-up...
83  */
84 int zs_def_cflag = (CREAD | CS8 | HUPCL);
85 
86 
87 #define PCLK		10000000	/* PCLK pin input clock rate */
88 
89 #ifndef ZS_DEFSPEED
90 #define ZS_DEFSPEED	9600
91 #endif
92 
93 /*
94  * Define interrupt levels.
95  */
96 #define ZSHARD_PRI 64
97 
98 /* Register recovery time is 3.5 to 4 PCLK Cycles */
99 #define ZS_RECOVERY	1		/* 1us = 10 PCLK Cycles */
100 #define ZS_DELAY()	delay(ZS_RECOVERY)
101 
102 /* The layout of this is hardware-dependent (padding, order). */
103 struct zschan {
104 	u_char   pad1[3];
105 	volatile u_char	zc_csr;		/* ctrl,status, and indirect access */
106 	u_char   pad2[3];
107 	volatile u_char	zc_data;	/* data */
108 };
109 struct zsdevice {
110 	/* Yes, they are backwards. */
111 	struct	zschan zs_chan_b;
112 	struct	zschan zs_chan_a;
113 };
114 
115 /* Return the byte offset of element within a structure */
116 #define OFFSET(struct_def, el)		((size_t)&((struct_def *)0)->el)
117 
118 #define ZS_CHAN_A	OFFSET(struct zsdevice, zs_chan_a)
119 #define ZS_CHAN_B	OFFSET(struct zsdevice, zs_chan_b)
120 #define ZS_REG_CSR	OFFSET(struct zschan, zc_csr)
121 #define ZS_REG_DATA	OFFSET(struct zschan, zc_data)
122 static int zs_chan_offset[] = {ZS_CHAN_A, ZS_CHAN_B};
123 
124 /* Flags from cninit() */
125 static int zs_hwflags[NZS][2];
126 
127 /* Default speed for all channels */
128 static int zs_defspeed = ZS_DEFSPEED;
129 static volatile int zssoftpending;
130 
131 static u_char zs_init_reg[16] = {
132 	0,				/* 0: CMD (reset, etc.) */
133 	0,				/* 1: No interrupts yet. */
134 	ZSHARD_PRI,			/* 2: IVECT */
135 	ZSWR3_RX_8 | ZSWR3_RX_ENABLE,
136 	ZSWR4_CLK_X16 | ZSWR4_ONESB,
137 	ZSWR5_TX_8 | ZSWR5_TX_ENABLE,
138 	0,				/* 6: TXSYNC/SYNCLO */
139 	0,				/* 7: RXSYNC/SYNCHI */
140 	0,				/* 8: alias for data port */
141 	ZSWR9_MASTER_IE,
142 	0,				/*10: Misc. TX/RX control bits */
143 	ZSWR11_TXCLK_BAUD | ZSWR11_RXCLK_BAUD | ZSWR11_TRXC_OUT_ENA,
144 	BPS_TO_TCONST(PCLK/16, ZS_DEFSPEED), /*12: BAUDLO (default=9600) */
145 	0,				/*13: BAUDHI (default=9600) */
146 	ZSWR14_BAUD_ENA | ZSWR14_BAUD_FROM_PCLK,
147 	ZSWR15_BREAK_IE,
148 };
149 
150 
151 /****************************************************************
152  * Autoconfig
153  ****************************************************************/
154 
155 /* Definition of the driver for autoconfig. */
156 static int	zs_match __P((struct device *, struct cfdata *, void *));
157 static void	zs_attach __P((struct device *, struct device *, void *));
158 static int	zs_print __P((void *, const char *name));
159 
160 CFATTACH_DECL(zsc, sizeof(struct zsc_softc),
161     zs_match, zs_attach, NULL, NULL);
162 
163 extern struct	cfdriver zsc_cd;
164 
165 static int	zshard __P((void *));
166 void		zssoft __P((void *));
167 static int	zs_get_speed __P((struct zs_chanstate *));
168 struct		zschan *zs_get_chan_addr (int zs_unit, int channel);
169 int		zs_getc __P((void *));
170 void		zs_putc __P((void *, int));
171 
172 /*
173  * Is the zs chip present?
174  */
175 static int
176 zs_match(parent, cf, aux)
177 	struct device *parent;
178 	struct cfdata *cf;
179 	void *aux;
180 {
181 	struct confargs *ca = aux;
182 	void *va;
183 
184 	if (strcmp(ca->ca_name, "zsc"))
185 		return 0;
186 
187 	va = (void *)cf->cf_addr;
188 
189 	/* This returns -1 on a fault (bus error). */
190 	if (badaddr(va, 1))
191 		return 0;
192 	return 1;
193 }
194 
195 /*
196  * Attach a found zs.
197  *
198  * Match slave number to zs unit number, so that misconfiguration will
199  * not set up the keyboard as ttya, etc.
200  */
201 static void
202 zs_attach(parent, self, aux)
203 	struct device *parent;
204 	struct device *self;
205 	void *aux;
206 {
207 	struct zsc_softc *zsc = (void *) self;
208 	struct confargs *ca = aux;
209 	struct zsc_attach_args zsc_args;
210 	struct zs_chanstate *cs;
211 	struct zs_channel *ch;
212 	int    zs_unit, channel, s;
213 
214 	zsc->zsc_bustag = ca->ca_bustag;
215 	if (bus_space_map(ca->ca_bustag, ca->ca_addr,
216 			  sizeof(struct zsdevice),
217 			  BUS_SPACE_MAP_LINEAR,
218 			  &zsc->zsc_base) != 0) {
219 		printf(": cannot map registers\n");
220 		return;
221 	}
222 
223 	zs_unit = zsc->zsc_dev.dv_unit;
224 	printf("\n");
225 
226 	/*
227 	 * Initialize software state for each channel.
228 	 */
229 	for (channel = 0; channel < 2; channel++) {
230 		zsc_args.channel = channel;
231 		zsc_args.hwflags = zs_hwflags[zs_unit][channel];
232 		ch = &zsc->zsc_cs_store[channel];
233 		cs = zsc->zsc_cs[channel] = (struct zs_chanstate *)ch;
234 
235 		simple_lock_init(&cs->cs_lock);
236 		cs->cs_reg_csr = NULL;
237 		cs->cs_reg_data = NULL;
238 		cs->cs_channel = channel;
239 		cs->cs_private = NULL;
240 		cs->cs_ops = &zsops_null;
241 		cs->cs_brg_clk = PCLK / 16;
242 
243 		if (bus_space_subregion(ca->ca_bustag, zsc->zsc_base,
244 					zs_chan_offset[channel],
245 					sizeof(struct zschan),
246 					&ch->cs_regs) != 0) {
247 			printf(": cannot map regs\n");
248 			return;
249 		}
250 		ch->cs_bustag = ca->ca_bustag;
251 
252 		memcpy(cs->cs_creg, zs_init_reg, 16);
253 		memcpy(cs->cs_preg, zs_init_reg, 16);
254 
255 		if (zsc_args.hwflags & ZS_HWFLAG_CONSOLE)
256 			cs->cs_defspeed = zs_get_speed(cs);
257 		else
258 			cs->cs_defspeed = zs_defspeed;
259 		cs->cs_defcflag = zs_def_cflag;
260 
261 		/* Make these correspond to cs_defcflag (-crtscts) */
262 		cs->cs_rr0_dcd = ZSRR0_DCD;
263 		cs->cs_rr0_cts = 0;
264 		cs->cs_wr5_dtr = ZSWR5_DTR | ZSWR5_RTS;
265 		cs->cs_wr5_rts = 0;
266 
267 		/*
268 		 * Clear the master interrupt enable.
269 		 * The INTENA is common to both channels,
270 		 * so just do it on the A channel.
271 		 */
272 		if (channel == 0) {
273 			zs_write_reg(cs, 9, 0);
274 		}
275 		/*
276 		 * Look for a child driver for this channel.
277 		 * The child attach will setup the hardware.
278 		 */
279 		if (!config_found(self, (void *)&zsc_args, zs_print)) {
280 			/* No sub-driver.  Just reset it. */
281 			u_char reset = (channel == 0) ?
282 				ZSWR9_A_RESET : ZSWR9_B_RESET;
283 
284 			s = splhigh();
285  			zs_write_reg(cs,  9, reset);
286 			splx(s);
287 		}
288 	}
289 
290 
291 	zsc->sc_si = softintr_establish(IPL_SOFTSERIAL, zssoft, zsc);
292 	bus_intr_establish(zsc->zsc_bustag, SYS_INTR_SCC0, 0, 0, zshard, NULL);
293 
294 	evcnt_attach_dynamic(&zsc->zs_intrcnt, EVCNT_TYPE_INTR, NULL,
295 			     self->dv_xname, "intr");
296 
297 	/*
298 	 * Set the master interrupt enable and interrupt vector.
299 	 * (common to both channels, do it on A)
300 	 */
301 	cs = zsc->zsc_cs[0];
302 	s = splhigh();
303 	/* interrupt vector */
304 	zs_write_reg(cs, 2, zs_init_reg[2]);
305 	/* master interrupt control (enable) */
306 	zs_write_reg(cs, 9, zs_init_reg[9]);
307 	splx(s);
308 }
309 
310 static int
311 zs_print(aux, name)
312 	void *aux;
313 	const char *name;
314 {
315 	struct zsc_attach_args *args = aux;
316 
317 	if (name != NULL)
318 		aprint_normal("%s: ", name);
319 
320 	if (args->channel != -1)
321 		aprint_normal(" channel %d", args->channel);
322 
323 	return UNCONF;
324 }
325 
326 /*
327  * Our ZS chips all share a common, autovectored interrupt,
328  * so we have to look at all of them on each interrupt.
329  */
330 static int
331 zshard(arg)
332 	void *arg;
333 {
334 	register struct zsc_softc *zsc;
335 	register int unit, rval, softreq;
336 
337 	rval = 0;
338 	for (unit = 0; unit < zsc_cd.cd_ndevs; unit++) {
339 		zsc = zsc_cd.cd_devs[unit];
340 		if (zsc == NULL)
341 			continue;
342 		rval |= zsc_intr_hard(zsc);
343 		softreq = zsc->zsc_cs[0]->cs_softreq;
344 		softreq |= zsc->zsc_cs[1]->cs_softreq;
345 		if (softreq && (zssoftpending == 0)) {
346 		    zssoftpending = 1;
347 		    softintr_schedule(zsc->sc_si);
348 		}
349 		zsc->zs_intrcnt.ev_count++;
350 	}
351 	return rval;
352 }
353 
354 /*
355  * Similar scheme as for zshard (look at all of them)
356  */
357 void
358 zssoft(arg)
359 	void *arg;
360 {
361 	register struct zsc_softc *zsc;
362 	register int s, unit;
363 
364 	/* This is not the only ISR on this IPL. */
365 	if (zssoftpending == 0)
366 		return;
367 
368 	/*
369 	 * The soft intr. bit will be set by zshard only if
370 	 * the variable zssoftpending is zero.  The order of
371 	 * these next two statements prevents our clearing
372 	 * the soft intr bit just after zshard has set it.
373 	 */
374 	/*isr_soft_clear(ZSSOFT_PRI);*/
375 	zssoftpending = 0;
376 
377 	/* Make sure we call the tty layer at spltty. */
378 	s = spltty();
379 	for (unit = 0; unit < zsc_cd.cd_ndevs; unit++) {
380 		zsc = zsc_cd.cd_devs[unit];
381 		if (zsc == NULL)
382 			continue;
383 		(void) zsc_intr_soft(zsc);
384 	}
385 	splx(s);
386 	return;
387 }
388 
389 
390 /*
391  * Compute the current baud rate given a ZS channel.
392  */
393 static int
394 zs_get_speed(cs)
395 	struct zs_chanstate *cs;
396 {
397 	int tconst;
398 
399 	tconst = zs_read_reg(cs, 12);
400 	tconst |= zs_read_reg(cs, 13) << 8;
401 	return (TCONST_TO_BPS(cs->cs_brg_clk, tconst));
402 }
403 
404 /*
405  * MD functions for setting the baud rate and control modes.
406  */
407 int
408 zs_set_speed(cs, bps)
409 	struct zs_chanstate *cs;
410 	int bps;	/* bits per second */
411 {
412 	int tconst, real_bps;
413 
414 #if 0
415 	while (!(zs_read_csr(cs) & ZSRR0_TX_READY))
416 	        {/*nop*/}
417 #endif
418 	/* Wait for transmit buffer to empty */
419 	if (bps == 0) {
420 		return (0);
421 	}
422 
423 #ifdef	DIAGNOSTIC
424 	if (cs->cs_brg_clk == 0)
425 		panic("zs_set_speed");
426 #endif
427 
428 	tconst = BPS_TO_TCONST(cs->cs_brg_clk, bps);
429 	if (tconst < 0)
430 		return (EINVAL);
431 
432 	/* Convert back to make sure we can do it. */
433 	real_bps = TCONST_TO_BPS(cs->cs_brg_clk, tconst);
434 
435 	/* XXX - Allow some tolerance here? */
436 #if 0
437 	if (real_bps != bps)
438 		return (EINVAL);
439 #endif
440 
441 	cs->cs_preg[12] = tconst;
442 	cs->cs_preg[13] = tconst >> 8;
443 
444 	/* Caller will stuff the pending registers. */
445 	return (0);
446 }
447 
448 int
449 zs_set_modes(cs, cflag)
450 	struct zs_chanstate *cs;
451 	int cflag;	/* bits per second */
452 {
453 	int s;
454 
455 	/*
456 	 * Output hardware flow control on the chip is horrendous:
457 	 * if carrier detect drops, the receiver is disabled, and if
458 	 * CTS drops, the transmitter is stoped IN MID CHARACTER!
459 	 * Therefore, NEVER set the HFC bit, and instead use the
460 	 * status interrupt to detect CTS changes.
461 	 */
462 	s = splzs();
463 	cs->cs_rr0_pps = 0;
464 	if ((cflag & (CLOCAL | MDMBUF)) != 0) {
465 		cs->cs_rr0_dcd = 0;
466 		if ((cflag & MDMBUF) == 0)
467 			cs->cs_rr0_pps = ZSRR0_DCD;
468 	} else
469 		cs->cs_rr0_dcd = ZSRR0_DCD;
470 	if ((cflag & CRTSCTS) != 0) {
471 		cs->cs_wr5_dtr = ZSWR5_DTR;
472 		cs->cs_wr5_rts = ZSWR5_RTS;
473 		cs->cs_rr0_cts = ZSRR0_CTS;
474 	} else if ((cflag & MDMBUF) != 0) {
475 		cs->cs_wr5_dtr = 0;
476 		cs->cs_wr5_rts = ZSWR5_DTR;
477 		cs->cs_rr0_cts = ZSRR0_DCD;
478 	} else {
479 		cs->cs_wr5_dtr = ZSWR5_DTR | ZSWR5_RTS;
480 		cs->cs_wr5_rts = 0;
481 		cs->cs_rr0_cts = 0;
482 	}
483 	splx(s);
484 
485 	/* Caller will stuff the pending registers. */
486 	return (0);
487 }
488 
489 
490 /*
491  * Read or write the chip with suitable delays.
492  */
493 
494 u_char
495 zs_read_reg(cs, reg)
496 	struct zs_chanstate *cs;
497 	u_char reg;
498 {
499 	u_char val;
500 	struct zs_channel *zsc = (struct zs_channel *)cs;
501 
502 	bus_space_write_1(zsc->cs_bustag, zsc->cs_regs, ZS_REG_CSR, reg);
503 	ZS_DELAY();
504 	val = bus_space_read_1(zsc->cs_bustag, zsc->cs_regs, ZS_REG_CSR);
505 	ZS_DELAY();
506 	return val;
507 }
508 
509 void
510 zs_write_reg(cs, reg, val)
511 	struct zs_chanstate *cs;
512 	u_char reg, val;
513 {
514 	struct zs_channel *zsc = (struct zs_channel *)cs;
515 
516 	bus_space_write_1(zsc->cs_bustag, zsc->cs_regs, ZS_REG_CSR, reg);
517 	ZS_DELAY();
518 	bus_space_write_1(zsc->cs_bustag, zsc->cs_regs, ZS_REG_CSR, val);
519 	ZS_DELAY();
520 }
521 
522 u_char zs_read_csr(cs)
523 	struct zs_chanstate *cs;
524 {
525 	struct zs_channel *zsc = (struct zs_channel *)cs;
526 	register u_char val;
527 
528 	val = bus_space_read_1(zsc->cs_bustag, zsc->cs_regs, ZS_REG_CSR);
529 	ZS_DELAY();
530 	return val;
531 }
532 
533 void  zs_write_csr(cs, val)
534 	struct zs_chanstate *cs;
535 	u_char val;
536 {
537 	struct zs_channel *zsc = (struct zs_channel *)cs;
538 
539 	bus_space_write_1(zsc->cs_bustag, zsc->cs_regs, ZS_REG_CSR, val);
540 	ZS_DELAY();
541 }
542 
543 u_char zs_read_data(cs)
544 	struct zs_chanstate *cs;
545 {
546 	struct zs_channel *zsc = (struct zs_channel *)cs;
547 	register u_char val;
548 
549 	val = bus_space_read_1(zsc->cs_bustag, zsc->cs_regs, ZS_REG_DATA);
550 	ZS_DELAY();
551 	return val;
552 }
553 
554 void  zs_write_data(cs, val)
555 	struct zs_chanstate *cs;
556 	u_char val;
557 {
558 	struct zs_channel *zsc = (struct zs_channel *)cs;
559 
560 	bus_space_write_1(zsc->cs_bustag, zsc->cs_regs, ZS_REG_DATA, val);
561 	ZS_DELAY();
562 }
563 
564 void
565 zs_abort(cs)
566 	struct zs_chanstate *cs;
567 {
568 #if defined(KGDB)
569 	zskgdb(cs);
570 #elif defined(DDB)
571 	Debugger();
572 #endif
573 }
574 
575 
576 /*********************************************************/
577 /*  Polled character I/O functions for console and KGDB  */
578 /*********************************************************/
579 
580 struct zschan *
581 zs_get_chan_addr(zs_unit, channel)
582         int zs_unit, channel;
583 {
584         struct zsdevice *addr;
585         struct zschan *zc;
586 
587         if (zs_unit >= NZS)
588                 return NULL;
589 
590         addr = (struct zsdevice *) ZS0_ADDR;
591 
592         if (channel == 0) {
593                 zc = &addr->zs_chan_a;
594         } else {
595                 zc = &addr->zs_chan_b;
596         }
597         return (zc);
598 }
599 
600 int
601 zs_getc(arg)
602 	void *arg;
603 {
604 	register volatile struct zschan *zc = arg;
605 	register int s, c, rr0;
606 
607 	s = splhigh();
608 	/* Wait for a character to arrive. */
609 	do {
610 		rr0 = zc->zc_csr;
611 		ZS_DELAY();
612 	} while ((rr0 & ZSRR0_RX_READY) == 0);
613 
614 	c = zc->zc_data;
615 	ZS_DELAY();
616 	splx(s);
617 
618 	return (c);
619 }
620 
621 /*
622  * Polled output char.
623  */
624 void
625 zs_putc(arg, c)
626 	void *arg;
627 	int c;
628 {
629 	register volatile struct zschan *zc = arg;
630 	register int s, rr0;
631 
632 	s = splhigh();
633 	/* Wait for transmitter to become ready. */
634 	do {
635 		rr0 = zc->zc_csr;
636 		ZS_DELAY();
637 	} while ((rr0 & ZSRR0_TX_READY) == 0);
638 
639 	zc->zc_data = c;
640 	wbflush();
641 	ZS_DELAY();
642 	splx(s);
643 }
644 
645 /***************************************************************/
646 
647 static void zscnprobe __P((struct consdev *));
648 static void zscninit __P((struct consdev *));
649 static int  zscngetc __P((dev_t));
650 static void zscnputc __P((dev_t, int));
651 static void zscnpollc __P((dev_t, int));
652 
653 static int  cons_port;
654 
655 struct consdev consdev_zs = {
656 	zscnprobe,
657 	zscninit,
658 	zscngetc,
659 	zscnputc,
660 	zscnpollc
661 };
662 
663 void
664 zscnprobe(cn)
665 	struct consdev *cn;
666 {
667 }
668 
669 void
670 zscninit(cn)
671 	struct consdev *cn;
672 {
673 	extern const struct cdevsw zstty_cdevsw;
674 
675 	cons_port = prom_getconsole();
676 	cn->cn_dev = makedev(cdevsw_lookup_major(&zstty_cdevsw), cons_port);
677 	cn->cn_pri = CN_REMOTE;
678 	zs_hwflags[0][cons_port] = ZS_HWFLAG_CONSOLE;
679 }
680 
681 int
682 zscngetc(dev)
683 	dev_t dev;
684 {
685 	struct zschan *zs;
686 
687 	zs = zs_get_chan_addr(0, cons_port);
688 	return zs_getc(zs);
689 }
690 
691 void
692 zscnputc(dev, c)
693 	dev_t dev;
694 	int c;
695 {
696 	struct zschan *zs;
697 
698 	zs = zs_get_chan_addr(0, cons_port);
699 	zs_putc(zs, c);
700 }
701 
702 void
703 zscnpollc(dev, on)
704 	dev_t dev;
705 	int on;
706 {
707 }
708