xref: /netbsd-src/sys/arch/mipsco/obio/zs.c (revision aaf4ece63a859a04e37cf3a7229b5fab0157cc06)
1 /*	$NetBSD: zs.c,v 1.18 2005/12/11 12:18:13 christos 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 <sys/cdefs.h>
47 __KERNEL_RCSID(0, "$NetBSD: zs.c,v 1.18 2005/12/11 12:18:13 christos Exp $");
48 
49 #include "opt_ddb.h"
50 #include "opt_kgdb.h"
51 
52 #include <sys/param.h>
53 #include <sys/systm.h>
54 #include <sys/conf.h>
55 #include <sys/device.h>
56 #include <sys/file.h>
57 #include <sys/ioctl.h>
58 #include <sys/kernel.h>
59 #include <sys/proc.h>
60 #include <sys/tty.h>
61 #include <sys/time.h>
62 #include <sys/syslog.h>
63 
64 #include <machine/cpu.h>
65 #include <machine/mainboard.h>
66 #include <machine/autoconf.h>
67 #include <machine/prom.h>
68 #include <machine/z8530var.h>
69 
70 #include <dev/cons.h>
71 #include <dev/ic/z8530reg.h>
72 
73 #include "zsc.h"	/* NZSC */
74 #define NZS NZSC
75 
76 /* Make life easier for the initialized arrays here. */
77 #if NZS < 2
78 #undef  NZS
79 #define NZS 2
80 #endif
81 
82 /*
83  * Some warts needed by z8530tty.c -
84  * The default parity REALLY needs to be the same as the PROM uses,
85  * or you can not see messages done with printf during boot-up...
86  */
87 int zs_def_cflag = (CREAD | CS8 | HUPCL);
88 
89 
90 #define PCLK		10000000	/* PCLK pin input clock rate */
91 
92 #ifndef ZS_DEFSPEED
93 #define ZS_DEFSPEED	9600
94 #endif
95 
96 /*
97  * Define interrupt levels.
98  */
99 #define ZSHARD_PRI 64
100 
101 /* Register recovery time is 3.5 to 4 PCLK Cycles */
102 #define ZS_RECOVERY	1		/* 1us = 10 PCLK Cycles */
103 #define ZS_DELAY()	delay(ZS_RECOVERY)
104 
105 /* The layout of this is hardware-dependent (padding, order). */
106 struct zschan {
107 	u_char   pad1[3];
108 	volatile u_char	zc_csr;		/* ctrl,status, and indirect access */
109 	u_char   pad2[3];
110 	volatile u_char	zc_data;	/* data */
111 };
112 struct zsdevice {
113 	/* Yes, they are backwards. */
114 	struct	zschan zs_chan_b;
115 	struct	zschan zs_chan_a;
116 };
117 
118 /* Return the byte offset of element within a structure */
119 #define OFFSET(struct_def, el)		((size_t)&((struct_def *)0)->el)
120 
121 #define ZS_CHAN_A	OFFSET(struct zsdevice, zs_chan_a)
122 #define ZS_CHAN_B	OFFSET(struct zsdevice, zs_chan_b)
123 #define ZS_REG_CSR	OFFSET(struct zschan, zc_csr)
124 #define ZS_REG_DATA	OFFSET(struct zschan, zc_data)
125 static int zs_chan_offset[] = {ZS_CHAN_A, ZS_CHAN_B};
126 
127 /* Flags from cninit() */
128 static int zs_hwflags[NZS][2];
129 
130 /* Default speed for all channels */
131 static int zs_defspeed = ZS_DEFSPEED;
132 static volatile int zssoftpending;
133 
134 static u_char zs_init_reg[16] = {
135 	0,				/* 0: CMD (reset, etc.) */
136 	0,				/* 1: No interrupts yet. */
137 	ZSHARD_PRI,			/* 2: IVECT */
138 	ZSWR3_RX_8 | ZSWR3_RX_ENABLE,
139 	ZSWR4_CLK_X16 | ZSWR4_ONESB,
140 	ZSWR5_TX_8 | ZSWR5_TX_ENABLE,
141 	0,				/* 6: TXSYNC/SYNCLO */
142 	0,				/* 7: RXSYNC/SYNCHI */
143 	0,				/* 8: alias for data port */
144 	ZSWR9_MASTER_IE,
145 	0,				/*10: Misc. TX/RX control bits */
146 	ZSWR11_TXCLK_BAUD | ZSWR11_RXCLK_BAUD | ZSWR11_TRXC_OUT_ENA,
147 	BPS_TO_TCONST(PCLK/16, ZS_DEFSPEED), /*12: BAUDLO (default=9600) */
148 	0,				/*13: BAUDHI (default=9600) */
149 	ZSWR14_BAUD_ENA | ZSWR14_BAUD_FROM_PCLK,
150 	ZSWR15_BREAK_IE,
151 };
152 
153 
154 /****************************************************************
155  * Autoconfig
156  ****************************************************************/
157 
158 /* Definition of the driver for autoconfig. */
159 static int	zs_match __P((struct device *, struct cfdata *, void *));
160 static void	zs_attach __P((struct device *, struct device *, void *));
161 static int	zs_print __P((void *, const char *name));
162 
163 CFATTACH_DECL(zsc, sizeof(struct zsc_softc),
164     zs_match, zs_attach, NULL, NULL);
165 
166 extern struct	cfdriver zsc_cd;
167 
168 static int	zshard __P((void *));
169 void		zssoft __P((void *));
170 static int	zs_get_speed __P((struct zs_chanstate *));
171 struct		zschan *zs_get_chan_addr (int zs_unit, int channel);
172 int		zs_getc __P((void *));
173 void		zs_putc __P((void *, int));
174 
175 /*
176  * Is the zs chip present?
177  */
178 static int
179 zs_match(parent, cf, aux)
180 	struct device *parent;
181 	struct cfdata *cf;
182 	void *aux;
183 {
184 	struct confargs *ca = aux;
185 	void *va;
186 
187 	if (strcmp(ca->ca_name, "zsc"))
188 		return 0;
189 
190 	va = (void *)cf->cf_addr;
191 
192 	/* This returns -1 on a fault (bus error). */
193 	if (badaddr(va, 1))
194 		return 0;
195 	return 1;
196 }
197 
198 /*
199  * Attach a found zs.
200  *
201  * Match slave number to zs unit number, so that misconfiguration will
202  * not set up the keyboard as ttya, etc.
203  */
204 static void
205 zs_attach(parent, self, aux)
206 	struct device *parent;
207 	struct device *self;
208 	void *aux;
209 {
210 	struct zsc_softc *zsc = (void *) self;
211 	struct confargs *ca = aux;
212 	struct zsc_attach_args zsc_args;
213 	struct zs_chanstate *cs;
214 	struct zs_channel *ch;
215 	int    zs_unit, channel, s;
216 
217 	zsc->zsc_bustag = ca->ca_bustag;
218 	if (bus_space_map(ca->ca_bustag, ca->ca_addr,
219 			  sizeof(struct zsdevice),
220 			  BUS_SPACE_MAP_LINEAR,
221 			  &zsc->zsc_base) != 0) {
222 		printf(": cannot map registers\n");
223 		return;
224 	}
225 
226 	zs_unit = zsc->zsc_dev.dv_unit;
227 	printf("\n");
228 
229 	/*
230 	 * Initialize software state for each channel.
231 	 */
232 	for (channel = 0; channel < 2; channel++) {
233 		zsc_args.channel = channel;
234 		zsc_args.hwflags = zs_hwflags[zs_unit][channel];
235 		ch = &zsc->zsc_cs_store[channel];
236 		cs = zsc->zsc_cs[channel] = (struct zs_chanstate *)ch;
237 
238 		simple_lock_init(&cs->cs_lock);
239 		cs->cs_reg_csr = NULL;
240 		cs->cs_reg_data = NULL;
241 		cs->cs_channel = channel;
242 		cs->cs_private = NULL;
243 		cs->cs_ops = &zsops_null;
244 		cs->cs_brg_clk = PCLK / 16;
245 
246 		if (bus_space_subregion(ca->ca_bustag, zsc->zsc_base,
247 					zs_chan_offset[channel],
248 					sizeof(struct zschan),
249 					&ch->cs_regs) != 0) {
250 			printf(": cannot map regs\n");
251 			return;
252 		}
253 		ch->cs_bustag = ca->ca_bustag;
254 
255 		memcpy(cs->cs_creg, zs_init_reg, 16);
256 		memcpy(cs->cs_preg, zs_init_reg, 16);
257 
258 		if (zsc_args.hwflags & ZS_HWFLAG_CONSOLE)
259 			cs->cs_defspeed = zs_get_speed(cs);
260 		else
261 			cs->cs_defspeed = zs_defspeed;
262 		cs->cs_defcflag = zs_def_cflag;
263 
264 		/* Make these correspond to cs_defcflag (-crtscts) */
265 		cs->cs_rr0_dcd = ZSRR0_DCD;
266 		cs->cs_rr0_cts = 0;
267 		cs->cs_wr5_dtr = ZSWR5_DTR | ZSWR5_RTS;
268 		cs->cs_wr5_rts = 0;
269 
270 		/*
271 		 * Clear the master interrupt enable.
272 		 * The INTENA is common to both channels,
273 		 * so just do it on the A channel.
274 		 */
275 		if (channel == 0) {
276 			zs_write_reg(cs, 9, 0);
277 		}
278 		/*
279 		 * Look for a child driver for this channel.
280 		 * The child attach will setup the hardware.
281 		 */
282 		if (!config_found(self, (void *)&zsc_args, zs_print)) {
283 			/* No sub-driver.  Just reset it. */
284 			u_char reset = (channel == 0) ?
285 				ZSWR9_A_RESET : ZSWR9_B_RESET;
286 
287 			s = splhigh();
288  			zs_write_reg(cs,  9, reset);
289 			splx(s);
290 		}
291 	}
292 
293 
294 	zsc->sc_si = softintr_establish(IPL_SOFTSERIAL, zssoft, zsc);
295 	bus_intr_establish(zsc->zsc_bustag, SYS_INTR_SCC0, 0, 0, zshard, NULL);
296 
297 	evcnt_attach_dynamic(&zsc->zs_intrcnt, EVCNT_TYPE_INTR, NULL,
298 			     self->dv_xname, "intr");
299 
300 	/*
301 	 * Set the master interrupt enable and interrupt vector.
302 	 * (common to both channels, do it on A)
303 	 */
304 	cs = zsc->zsc_cs[0];
305 	s = splhigh();
306 	/* interrupt vector */
307 	zs_write_reg(cs, 2, zs_init_reg[2]);
308 	/* master interrupt control (enable) */
309 	zs_write_reg(cs, 9, zs_init_reg[9]);
310 	splx(s);
311 }
312 
313 static int
314 zs_print(aux, name)
315 	void *aux;
316 	const char *name;
317 {
318 	struct zsc_attach_args *args = aux;
319 
320 	if (name != NULL)
321 		aprint_normal("%s: ", name);
322 
323 	if (args->channel != -1)
324 		aprint_normal(" channel %d", args->channel);
325 
326 	return UNCONF;
327 }
328 
329 /*
330  * Our ZS chips all share a common, autovectored interrupt,
331  * so we have to look at all of them on each interrupt.
332  */
333 static int
334 zshard(arg)
335 	void *arg;
336 {
337 	register struct zsc_softc *zsc;
338 	register int unit, rval, softreq;
339 
340 	rval = 0;
341 	for (unit = 0; unit < zsc_cd.cd_ndevs; unit++) {
342 		zsc = zsc_cd.cd_devs[unit];
343 		if (zsc == NULL)
344 			continue;
345 		rval |= zsc_intr_hard(zsc);
346 		softreq = zsc->zsc_cs[0]->cs_softreq;
347 		softreq |= zsc->zsc_cs[1]->cs_softreq;
348 		if (softreq && (zssoftpending == 0)) {
349 		    zssoftpending = 1;
350 		    softintr_schedule(zsc->sc_si);
351 		}
352 		zsc->zs_intrcnt.ev_count++;
353 	}
354 	return rval;
355 }
356 
357 /*
358  * Similar scheme as for zshard (look at all of them)
359  */
360 void
361 zssoft(arg)
362 	void *arg;
363 {
364 	register struct zsc_softc *zsc;
365 	register int s, unit;
366 
367 	/* This is not the only ISR on this IPL. */
368 	if (zssoftpending == 0)
369 		return;
370 
371 	/*
372 	 * The soft intr. bit will be set by zshard only if
373 	 * the variable zssoftpending is zero.  The order of
374 	 * these next two statements prevents our clearing
375 	 * the soft intr bit just after zshard has set it.
376 	 */
377 	/*isr_soft_clear(ZSSOFT_PRI);*/
378 	zssoftpending = 0;
379 
380 	/* Make sure we call the tty layer at spltty. */
381 	s = spltty();
382 	for (unit = 0; unit < zsc_cd.cd_ndevs; unit++) {
383 		zsc = zsc_cd.cd_devs[unit];
384 		if (zsc == NULL)
385 			continue;
386 		(void) zsc_intr_soft(zsc);
387 	}
388 	splx(s);
389 	return;
390 }
391 
392 
393 /*
394  * Compute the current baud rate given a ZS channel.
395  */
396 static int
397 zs_get_speed(cs)
398 	struct zs_chanstate *cs;
399 {
400 	int tconst;
401 
402 	tconst = zs_read_reg(cs, 12);
403 	tconst |= zs_read_reg(cs, 13) << 8;
404 	return (TCONST_TO_BPS(cs->cs_brg_clk, tconst));
405 }
406 
407 /*
408  * MD functions for setting the baud rate and control modes.
409  */
410 int
411 zs_set_speed(cs, bps)
412 	struct zs_chanstate *cs;
413 	int bps;	/* bits per second */
414 {
415 	int tconst, real_bps;
416 
417 #if 0
418 	while (!(zs_read_csr(cs) & ZSRR0_TX_READY))
419 	        {/*nop*/}
420 #endif
421 	/* Wait for transmit buffer to empty */
422 	if (bps == 0) {
423 		return (0);
424 	}
425 
426 #ifdef	DIAGNOSTIC
427 	if (cs->cs_brg_clk == 0)
428 		panic("zs_set_speed");
429 #endif
430 
431 	tconst = BPS_TO_TCONST(cs->cs_brg_clk, bps);
432 	if (tconst < 0)
433 		return (EINVAL);
434 
435 	/* Convert back to make sure we can do it. */
436 	real_bps = TCONST_TO_BPS(cs->cs_brg_clk, tconst);
437 
438 	/* XXX - Allow some tolerance here? */
439 #if 0
440 	if (real_bps != bps)
441 		return (EINVAL);
442 #endif
443 
444 	cs->cs_preg[12] = tconst;
445 	cs->cs_preg[13] = tconst >> 8;
446 
447 	/* Caller will stuff the pending registers. */
448 	return (0);
449 }
450 
451 int
452 zs_set_modes(cs, cflag)
453 	struct zs_chanstate *cs;
454 	int cflag;	/* bits per second */
455 {
456 	int s;
457 
458 	/*
459 	 * Output hardware flow control on the chip is horrendous:
460 	 * if carrier detect drops, the receiver is disabled, and if
461 	 * CTS drops, the transmitter is stoped IN MID CHARACTER!
462 	 * Therefore, NEVER set the HFC bit, and instead use the
463 	 * status interrupt to detect CTS changes.
464 	 */
465 	s = splzs();
466 	cs->cs_rr0_pps = 0;
467 	if ((cflag & (CLOCAL | MDMBUF)) != 0) {
468 		cs->cs_rr0_dcd = 0;
469 		if ((cflag & MDMBUF) == 0)
470 			cs->cs_rr0_pps = ZSRR0_DCD;
471 	} else
472 		cs->cs_rr0_dcd = ZSRR0_DCD;
473 	if ((cflag & CRTSCTS) != 0) {
474 		cs->cs_wr5_dtr = ZSWR5_DTR;
475 		cs->cs_wr5_rts = ZSWR5_RTS;
476 		cs->cs_rr0_cts = ZSRR0_CTS;
477 	} else if ((cflag & MDMBUF) != 0) {
478 		cs->cs_wr5_dtr = 0;
479 		cs->cs_wr5_rts = ZSWR5_DTR;
480 		cs->cs_rr0_cts = ZSRR0_DCD;
481 	} else {
482 		cs->cs_wr5_dtr = ZSWR5_DTR | ZSWR5_RTS;
483 		cs->cs_wr5_rts = 0;
484 		cs->cs_rr0_cts = 0;
485 	}
486 	splx(s);
487 
488 	/* Caller will stuff the pending registers. */
489 	return (0);
490 }
491 
492 
493 /*
494  * Read or write the chip with suitable delays.
495  */
496 
497 u_char
498 zs_read_reg(cs, reg)
499 	struct zs_chanstate *cs;
500 	u_char reg;
501 {
502 	u_char val;
503 	struct zs_channel *zsc = (struct zs_channel *)cs;
504 
505 	bus_space_write_1(zsc->cs_bustag, zsc->cs_regs, ZS_REG_CSR, reg);
506 	ZS_DELAY();
507 	val = bus_space_read_1(zsc->cs_bustag, zsc->cs_regs, ZS_REG_CSR);
508 	ZS_DELAY();
509 	return val;
510 }
511 
512 void
513 zs_write_reg(cs, reg, val)
514 	struct zs_chanstate *cs;
515 	u_char reg, val;
516 {
517 	struct zs_channel *zsc = (struct zs_channel *)cs;
518 
519 	bus_space_write_1(zsc->cs_bustag, zsc->cs_regs, ZS_REG_CSR, reg);
520 	ZS_DELAY();
521 	bus_space_write_1(zsc->cs_bustag, zsc->cs_regs, ZS_REG_CSR, val);
522 	ZS_DELAY();
523 }
524 
525 u_char zs_read_csr(cs)
526 	struct zs_chanstate *cs;
527 {
528 	struct zs_channel *zsc = (struct zs_channel *)cs;
529 	register u_char val;
530 
531 	val = bus_space_read_1(zsc->cs_bustag, zsc->cs_regs, ZS_REG_CSR);
532 	ZS_DELAY();
533 	return val;
534 }
535 
536 void  zs_write_csr(cs, val)
537 	struct zs_chanstate *cs;
538 	u_char val;
539 {
540 	struct zs_channel *zsc = (struct zs_channel *)cs;
541 
542 	bus_space_write_1(zsc->cs_bustag, zsc->cs_regs, ZS_REG_CSR, val);
543 	ZS_DELAY();
544 }
545 
546 u_char zs_read_data(cs)
547 	struct zs_chanstate *cs;
548 {
549 	struct zs_channel *zsc = (struct zs_channel *)cs;
550 	register u_char val;
551 
552 	val = bus_space_read_1(zsc->cs_bustag, zsc->cs_regs, ZS_REG_DATA);
553 	ZS_DELAY();
554 	return val;
555 }
556 
557 void  zs_write_data(cs, val)
558 	struct zs_chanstate *cs;
559 	u_char val;
560 {
561 	struct zs_channel *zsc = (struct zs_channel *)cs;
562 
563 	bus_space_write_1(zsc->cs_bustag, zsc->cs_regs, ZS_REG_DATA, val);
564 	ZS_DELAY();
565 }
566 
567 void
568 zs_abort(cs)
569 	struct zs_chanstate *cs;
570 {
571 #if defined(KGDB)
572 	zskgdb(cs);
573 #elif defined(DDB)
574 	Debugger();
575 #endif
576 }
577 
578 
579 /*********************************************************/
580 /*  Polled character I/O functions for console and KGDB  */
581 /*********************************************************/
582 
583 struct zschan *
584 zs_get_chan_addr(zs_unit, channel)
585         int zs_unit, channel;
586 {
587         struct zsdevice *addr;
588         struct zschan *zc;
589 
590         if (zs_unit >= NZS)
591                 return NULL;
592 
593         addr = (struct zsdevice *) ZS0_ADDR;
594 
595         if (channel == 0) {
596                 zc = &addr->zs_chan_a;
597         } else {
598                 zc = &addr->zs_chan_b;
599         }
600         return (zc);
601 }
602 
603 int
604 zs_getc(arg)
605 	void *arg;
606 {
607 	register volatile struct zschan *zc = arg;
608 	register int s, c, rr0;
609 
610 	s = splhigh();
611 	/* Wait for a character to arrive. */
612 	do {
613 		rr0 = zc->zc_csr;
614 		ZS_DELAY();
615 	} while ((rr0 & ZSRR0_RX_READY) == 0);
616 
617 	c = zc->zc_data;
618 	ZS_DELAY();
619 	splx(s);
620 
621 	return (c);
622 }
623 
624 /*
625  * Polled output char.
626  */
627 void
628 zs_putc(arg, c)
629 	void *arg;
630 	int c;
631 {
632 	register volatile struct zschan *zc = arg;
633 	register int s, rr0;
634 
635 	s = splhigh();
636 	/* Wait for transmitter to become ready. */
637 	do {
638 		rr0 = zc->zc_csr;
639 		ZS_DELAY();
640 	} while ((rr0 & ZSRR0_TX_READY) == 0);
641 
642 	zc->zc_data = c;
643 	wbflush();
644 	ZS_DELAY();
645 	splx(s);
646 }
647 
648 /***************************************************************/
649 
650 static void zscnprobe __P((struct consdev *));
651 static void zscninit __P((struct consdev *));
652 static int  zscngetc __P((dev_t));
653 static void zscnputc __P((dev_t, int));
654 static void zscnpollc __P((dev_t, int));
655 
656 static int  cons_port;
657 
658 struct consdev consdev_zs = {
659 	zscnprobe,
660 	zscninit,
661 	zscngetc,
662 	zscnputc,
663 	zscnpollc
664 };
665 
666 void
667 zscnprobe(cn)
668 	struct consdev *cn;
669 {
670 }
671 
672 void
673 zscninit(cn)
674 	struct consdev *cn;
675 {
676 	extern const struct cdevsw zstty_cdevsw;
677 
678 	cons_port = prom_getconsole();
679 	cn->cn_dev = makedev(cdevsw_lookup_major(&zstty_cdevsw), cons_port);
680 	cn->cn_pri = CN_REMOTE;
681 	zs_hwflags[0][cons_port] = ZS_HWFLAG_CONSOLE;
682 }
683 
684 int
685 zscngetc(dev)
686 	dev_t dev;
687 {
688 	struct zschan *zs;
689 
690 	zs = zs_get_chan_addr(0, cons_port);
691 	return zs_getc(zs);
692 }
693 
694 void
695 zscnputc(dev, c)
696 	dev_t dev;
697 	int c;
698 {
699 	struct zschan *zs;
700 
701 	zs = zs_get_chan_addr(0, cons_port);
702 	zs_putc(zs, c);
703 }
704 
705 void
706 zscnpollc(dev, on)
707 	dev_t dev;
708 	int on;
709 {
710 }
711