xref: /netbsd/sys/arch/mipsco/obio/zs.c (revision c4a72b64)
1 /*	$NetBSD: zs.c,v 1.14 2002/10/02 05:38:11 thorpej 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 		cs->cs_reg_csr = NULL;
236 		cs->cs_reg_data = NULL;
237 		cs->cs_channel = channel;
238 		cs->cs_private = NULL;
239 		cs->cs_ops = &zsops_null;
240 		cs->cs_brg_clk = PCLK / 16;
241 
242 		if (bus_space_subregion(ca->ca_bustag, zsc->zsc_base,
243 					zs_chan_offset[channel],
244 					sizeof(struct zschan),
245 					&ch->cs_regs) != 0) {
246 			printf(": cannot map regs\n");
247 			return;
248 		}
249 		ch->cs_bustag = ca->ca_bustag;
250 
251 		memcpy(cs->cs_creg, zs_init_reg, 16);
252 		memcpy(cs->cs_preg, zs_init_reg, 16);
253 
254 		if (zsc_args.hwflags & ZS_HWFLAG_CONSOLE)
255 			cs->cs_defspeed = zs_get_speed(cs);
256 		else
257 			cs->cs_defspeed = zs_defspeed;
258 		cs->cs_defcflag = zs_def_cflag;
259 
260 		/* Make these correspond to cs_defcflag (-crtscts) */
261 		cs->cs_rr0_dcd = ZSRR0_DCD;
262 		cs->cs_rr0_cts = 0;
263 		cs->cs_wr5_dtr = ZSWR5_DTR | ZSWR5_RTS;
264 		cs->cs_wr5_rts = 0;
265 
266 		/*
267 		 * Clear the master interrupt enable.
268 		 * The INTENA is common to both channels,
269 		 * so just do it on the A channel.
270 		 */
271 		if (channel == 0) {
272 			zs_write_reg(cs, 9, 0);
273 		}
274 		/*
275 		 * Look for a child driver for this channel.
276 		 * The child attach will setup the hardware.
277 		 */
278 		if (!config_found(self, (void *)&zsc_args, zs_print)) {
279 			/* No sub-driver.  Just reset it. */
280 			u_char reset = (channel == 0) ?
281 				ZSWR9_A_RESET : ZSWR9_B_RESET;
282 
283 			s = splhigh();
284  			zs_write_reg(cs,  9, reset);
285 			splx(s);
286 		}
287 	}
288 
289 
290 	zsc->sc_si = softintr_establish(IPL_SOFTSERIAL, zssoft, zsc);
291 	bus_intr_establish(zsc->zsc_bustag, SYS_INTR_SCC0, 0, 0, zshard, NULL);
292 
293 	evcnt_attach_dynamic(&zsc->zs_intrcnt, EVCNT_TYPE_INTR, NULL,
294 			     self->dv_xname, "intr");
295 
296 	/*
297 	 * Set the master interrupt enable and interrupt vector.
298 	 * (common to both channels, do it on A)
299 	 */
300 	cs = zsc->zsc_cs[0];
301 	s = splhigh();
302 	/* interrupt vector */
303 	zs_write_reg(cs, 2, zs_init_reg[2]);
304 	/* master interrupt control (enable) */
305 	zs_write_reg(cs, 9, zs_init_reg[9]);
306 	splx(s);
307 }
308 
309 static int
310 zs_print(aux, name)
311 	void *aux;
312 	const char *name;
313 {
314 	struct zsc_attach_args *args = aux;
315 
316 	if (name != NULL)
317 		printf("%s: ", name);
318 
319 	if (args->channel != -1)
320 		printf(" channel %d", args->channel);
321 
322 	return UNCONF;
323 }
324 
325 /*
326  * Our ZS chips all share a common, autovectored interrupt,
327  * so we have to look at all of them on each interrupt.
328  */
329 static int
330 zshard(arg)
331 	void *arg;
332 {
333 	register struct zsc_softc *zsc;
334 	register int unit, rval, softreq;
335 
336 	rval = 0;
337 	for (unit = 0; unit < zsc_cd.cd_ndevs; unit++) {
338 		zsc = zsc_cd.cd_devs[unit];
339 		if (zsc == NULL)
340 			continue;
341 		rval |= zsc_intr_hard(zsc);
342 		softreq = zsc->zsc_cs[0]->cs_softreq;
343 		softreq |= zsc->zsc_cs[1]->cs_softreq;
344 		if (softreq && (zssoftpending == 0)) {
345 		    zssoftpending = 1;
346 		    softintr_schedule(zsc->sc_si);
347 		}
348 		zsc->zs_intrcnt.ev_count++;
349 	}
350 	return rval;
351 }
352 
353 /*
354  * Similar scheme as for zshard (look at all of them)
355  */
356 void
357 zssoft(arg)
358 	void *arg;
359 {
360 	register struct zsc_softc *zsc;
361 	register int s, unit;
362 
363 	/* This is not the only ISR on this IPL. */
364 	if (zssoftpending == 0)
365 		return;
366 
367 	/*
368 	 * The soft intr. bit will be set by zshard only if
369 	 * the variable zssoftpending is zero.  The order of
370 	 * these next two statements prevents our clearing
371 	 * the soft intr bit just after zshard has set it.
372 	 */
373 	/*isr_soft_clear(ZSSOFT_PRI);*/
374 	zssoftpending = 0;
375 
376 	/* Make sure we call the tty layer at spltty. */
377 	s = spltty();
378 	for (unit = 0; unit < zsc_cd.cd_ndevs; unit++) {
379 		zsc = zsc_cd.cd_devs[unit];
380 		if (zsc == NULL)
381 			continue;
382 		(void) zsc_intr_soft(zsc);
383 	}
384 	splx(s);
385 	return;
386 }
387 
388 
389 /*
390  * Compute the current baud rate given a ZS channel.
391  */
392 static int
393 zs_get_speed(cs)
394 	struct zs_chanstate *cs;
395 {
396 	int tconst;
397 
398 	tconst = zs_read_reg(cs, 12);
399 	tconst |= zs_read_reg(cs, 13) << 8;
400 	return (TCONST_TO_BPS(cs->cs_brg_clk, tconst));
401 }
402 
403 /*
404  * MD functions for setting the baud rate and control modes.
405  */
406 int
407 zs_set_speed(cs, bps)
408 	struct zs_chanstate *cs;
409 	int bps;	/* bits per second */
410 {
411 	int tconst, real_bps;
412 
413 #if 0
414 	while (!(zs_read_csr(cs) & ZSRR0_TX_READY))
415 	        {/*nop*/}
416 #endif
417 	/* Wait for transmit buffer to empty */
418 	if (bps == 0) {
419 		return (0);
420 	}
421 
422 #ifdef	DIAGNOSTIC
423 	if (cs->cs_brg_clk == 0)
424 		panic("zs_set_speed");
425 #endif
426 
427 	tconst = BPS_TO_TCONST(cs->cs_brg_clk, bps);
428 	if (tconst < 0)
429 		return (EINVAL);
430 
431 	/* Convert back to make sure we can do it. */
432 	real_bps = TCONST_TO_BPS(cs->cs_brg_clk, tconst);
433 
434 	/* XXX - Allow some tolerance here? */
435 #if 0
436 	if (real_bps != bps)
437 		return (EINVAL);
438 #endif
439 
440 	cs->cs_preg[12] = tconst;
441 	cs->cs_preg[13] = tconst >> 8;
442 
443 	/* Caller will stuff the pending registers. */
444 	return (0);
445 }
446 
447 int
448 zs_set_modes(cs, cflag)
449 	struct zs_chanstate *cs;
450 	int cflag;	/* bits per second */
451 {
452 	int s;
453 
454 	/*
455 	 * Output hardware flow control on the chip is horrendous:
456 	 * if carrier detect drops, the receiver is disabled, and if
457 	 * CTS drops, the transmitter is stoped IN MID CHARACTER!
458 	 * Therefore, NEVER set the HFC bit, and instead use the
459 	 * status interrupt to detect CTS changes.
460 	 */
461 	s = splzs();
462 	cs->cs_rr0_pps = 0;
463 	if ((cflag & (CLOCAL | MDMBUF)) != 0) {
464 		cs->cs_rr0_dcd = 0;
465 		if ((cflag & MDMBUF) == 0)
466 			cs->cs_rr0_pps = ZSRR0_DCD;
467 	} else
468 		cs->cs_rr0_dcd = ZSRR0_DCD;
469 	if ((cflag & CRTSCTS) != 0) {
470 		cs->cs_wr5_dtr = ZSWR5_DTR;
471 		cs->cs_wr5_rts = ZSWR5_RTS;
472 		cs->cs_rr0_cts = ZSRR0_CTS;
473 	} else if ((cflag & MDMBUF) != 0) {
474 		cs->cs_wr5_dtr = 0;
475 		cs->cs_wr5_rts = ZSWR5_DTR;
476 		cs->cs_rr0_cts = ZSRR0_DCD;
477 	} else {
478 		cs->cs_wr5_dtr = ZSWR5_DTR | ZSWR5_RTS;
479 		cs->cs_wr5_rts = 0;
480 		cs->cs_rr0_cts = 0;
481 	}
482 	splx(s);
483 
484 	/* Caller will stuff the pending registers. */
485 	return (0);
486 }
487 
488 
489 /*
490  * Read or write the chip with suitable delays.
491  */
492 
493 u_char
494 zs_read_reg(cs, reg)
495 	struct zs_chanstate *cs;
496 	u_char reg;
497 {
498 	u_char val;
499 	struct zs_channel *zsc = (struct zs_channel *)cs;
500 
501 	bus_space_write_1(zsc->cs_bustag, zsc->cs_regs, ZS_REG_CSR, reg);
502 	ZS_DELAY();
503 	val = bus_space_read_1(zsc->cs_bustag, zsc->cs_regs, ZS_REG_CSR);
504 	ZS_DELAY();
505 	return val;
506 }
507 
508 void
509 zs_write_reg(cs, reg, val)
510 	struct zs_chanstate *cs;
511 	u_char reg, val;
512 {
513 	struct zs_channel *zsc = (struct zs_channel *)cs;
514 
515 	bus_space_write_1(zsc->cs_bustag, zsc->cs_regs, ZS_REG_CSR, reg);
516 	ZS_DELAY();
517 	bus_space_write_1(zsc->cs_bustag, zsc->cs_regs, ZS_REG_CSR, val);
518 	ZS_DELAY();
519 }
520 
521 u_char zs_read_csr(cs)
522 	struct zs_chanstate *cs;
523 {
524 	struct zs_channel *zsc = (struct zs_channel *)cs;
525 	register u_char val;
526 
527 	val = bus_space_read_1(zsc->cs_bustag, zsc->cs_regs, ZS_REG_CSR);
528 	ZS_DELAY();
529 	return val;
530 }
531 
532 void  zs_write_csr(cs, val)
533 	struct zs_chanstate *cs;
534 	u_char val;
535 {
536 	struct zs_channel *zsc = (struct zs_channel *)cs;
537 
538 	bus_space_write_1(zsc->cs_bustag, zsc->cs_regs, ZS_REG_CSR, val);
539 	ZS_DELAY();
540 }
541 
542 u_char zs_read_data(cs)
543 	struct zs_chanstate *cs;
544 {
545 	struct zs_channel *zsc = (struct zs_channel *)cs;
546 	register u_char val;
547 
548 	val = bus_space_read_1(zsc->cs_bustag, zsc->cs_regs, ZS_REG_DATA);
549 	ZS_DELAY();
550 	return val;
551 }
552 
553 void  zs_write_data(cs, val)
554 	struct zs_chanstate *cs;
555 	u_char val;
556 {
557 	struct zs_channel *zsc = (struct zs_channel *)cs;
558 
559 	bus_space_write_1(zsc->cs_bustag, zsc->cs_regs, ZS_REG_DATA, val);
560 	ZS_DELAY();
561 }
562 
563 void
564 zs_abort(cs)
565 	struct zs_chanstate *cs;
566 {
567 #if defined(KGDB)
568 	zskgdb(cs);
569 #elif defined(DDB)
570 	Debugger();
571 #endif
572 }
573 
574 
575 /*********************************************************/
576 /*  Polled character I/O functions for console and KGDB  */
577 /*********************************************************/
578 
579 struct zschan *
580 zs_get_chan_addr(zs_unit, channel)
581         int zs_unit, channel;
582 {
583         struct zsdevice *addr;
584         struct zschan *zc;
585 
586         if (zs_unit >= NZS)
587                 return NULL;
588 
589         addr = (struct zsdevice *) ZS0_ADDR;
590 
591         if (channel == 0) {
592                 zc = &addr->zs_chan_a;
593         } else {
594                 zc = &addr->zs_chan_b;
595         }
596         return (zc);
597 }
598 
599 int
600 zs_getc(arg)
601 	void *arg;
602 {
603 	register volatile struct zschan *zc = arg;
604 	register int s, c, rr0;
605 
606 	s = splhigh();
607 	/* Wait for a character to arrive. */
608 	do {
609 		rr0 = zc->zc_csr;
610 		ZS_DELAY();
611 	} while ((rr0 & ZSRR0_RX_READY) == 0);
612 
613 	c = zc->zc_data;
614 	ZS_DELAY();
615 	splx(s);
616 
617 	return (c);
618 }
619 
620 /*
621  * Polled output char.
622  */
623 void
624 zs_putc(arg, c)
625 	void *arg;
626 	int c;
627 {
628 	register volatile struct zschan *zc = arg;
629 	register int s, rr0;
630 
631 	s = splhigh();
632 	/* Wait for transmitter to become ready. */
633 	do {
634 		rr0 = zc->zc_csr;
635 		ZS_DELAY();
636 	} while ((rr0 & ZSRR0_TX_READY) == 0);
637 
638 	zc->zc_data = c;
639 	wbflush();
640 	ZS_DELAY();
641 	splx(s);
642 }
643 
644 /***************************************************************/
645 
646 static void zscnprobe __P((struct consdev *));
647 static void zscninit __P((struct consdev *));
648 static int  zscngetc __P((dev_t));
649 static void zscnputc __P((dev_t, int));
650 static void zscnpollc __P((dev_t, int));
651 
652 static int  cons_port;
653 
654 struct consdev consdev_zs = {
655 	zscnprobe,
656 	zscninit,
657 	zscngetc,
658 	zscnputc,
659 	zscnpollc
660 };
661 
662 void
663 zscnprobe(cn)
664 	struct consdev *cn;
665 {
666 }
667 
668 void
669 zscninit(cn)
670 	struct consdev *cn;
671 {
672 	extern const struct cdevsw zstty_cdevsw;
673 
674 	cons_port = prom_getconsole();
675 	cn->cn_dev = makedev(cdevsw_lookup_major(&zstty_cdevsw), cons_port);
676 	cn->cn_pri = CN_REMOTE;
677 	zs_hwflags[0][cons_port] = ZS_HWFLAG_CONSOLE;
678 }
679 
680 int
681 zscngetc(dev)
682 	dev_t dev;
683 {
684 	struct zschan *zs;
685 
686 	zs = zs_get_chan_addr(0, cons_port);
687 	return zs_getc(zs);
688 }
689 
690 void
691 zscnputc(dev, c)
692 	dev_t dev;
693 	int c;
694 {
695 	struct zschan *zs;
696 
697 	zs = zs_get_chan_addr(0, cons_port);
698 	zs_putc(zs, c);
699 }
700 
701 void
702 zscnpollc(dev, on)
703 	dev_t dev;
704 	int on;
705 {
706 }
707